Rozprawy doktorskie: „Lipid biomarkers”

1

Blyth, Alison. "Lipid biomarkers in speleothems". Thesis, University of Newcastle Upon Tyne, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435638.

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Fullarton, J. Gregor. "Lipid biomarkers in marine symbiotic systems". Thesis, University of Stirling, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384931.

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Kneeland, Jessie M. (Jessie Mary). "Lipid biomarkers of coral stress : calibration and exploration". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68888.

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Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Corals are increasingly threatened by warming sea surface temperatures and other anthropogenic changes. The delicate symbiosis between corals and their algal endosymbionts (zooxanthellae) is easily disrupted by thermal stress, leading to bleaching and eventual mortality. The use of lipid ratios as biomarkers of environmental conditions is well established. Coral biomass contains abundant lipids, and the potential of lipid parameters to diagnose thermal tolerance in zooxanthellae has been previously suggested. In this thesis, I explore the response of specific fatty acids, sterols, and thylakoid membrane lipids to thermal and disease stress in zooxanthellae grown in culture, as well as those isolated from living corals. I present the discovery of a bioactive thylakoid lipid within zooxanthellae cells, and show how this compound is selectively mobilized in thermally stressed cells. I present a plausible mechanism for the breakdown of this compound into products that may cause apoptosis and disrupt the coral-algal symbiosis, eventually causing bleaching. I present two new lipid biomarkers of thermal stress in zooxanthellae, the C18 fatty acid unsaturation ratio, and the fatty acid to sterol ratio. I calibrate the decline of these two parameters to levels of thermal stress comparable to those needed to cause bleaching. I further show that these parameters are sensitive to pathogen stress as well. In several case studies of diseased and thermally stressed corals, I demonstrate that these lipid biomarkers of coral stress may be applied to zooxanthellae isolated from environmental samples. I show that these same compounds are preserved within coral aragonite, which opens up the potential to retrieve lipid-based historical records of coral health from annual layers of coral skeleton. This work demonstrates the value of using lipid biomarkers to assess coral health and better understand the biochemical mechanisms of coral bleaching.
by Jessie Mary Kneeland.
Ph.D.

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4

Vereb, Heather A. "Biomarkers of Lipid Oxidation in the Oral Cavity". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/76887.

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Measuring lipid oxidation is useful as a means of monitoring oxidative stress, such as that induced by clinical conditions or environmental exposure. Characteristic volatile compounds, often with low threshold odors, are secondary products of lipid oxidation reactions. Metallic flavor in food and beverages has been linked with oxidation of lipids in the oral cavity. Breath, an emerging medium for analysis of internal condition, is one means of measuring the metal-induced lipid oxidation responsible for this flavor. This project analyzes the breath of human subjects, as well as lipid oxidation of in vitro samples to identify compounds responsible for producing metallic flavor, which result from the oxidation of lipids in the oral cavity. Because these analytes are found at extremely low (picomolar to nanomolar) concentrations, preconcentration of samples prior to gas chromatography-mass spectrometry analysis is crucial. This study utilizes both solid phase microextraction (SPME) and micromachined silicon micropreconcentrators to concentrate compounds in breath to optimize analysis.
Master of Science

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5

Creegan, Rhona. "Identification of plasma lipid biomarkers in Alzheimer's disease". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1340.

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Alzheimer’s disease (AD), the commonest form of dementia, is a chronic, progressive neurodegenerative disease which manifests clinically as a slow global decline in cognitive function, including deterioration of memory, reasoning, abstraction, language and emotional stability, culminating in a patient with end-stage disease, totally dependent on custodial care. With an ageing population, there is predicted to be a marked increase in the number of people diagnosed with AD in the coming decades, making this a significant challenge to socio-economic policy and aged care. Currently there is no cure for AD and while current therapies may temporarily ameliorate symptoms, death usually occurs approximately 8 years after diagnosis. Attention is now being directed to the discovery of biomarkers that may not only facilitate pre-symptomatic diagnosis but provide an insight into aberrant biochemical pathways that may reveal potential therapeutic targets. AD pathogenesis develops over many years before clinical symptoms appear, providing the opportunity to develop therapy that could slow or stop disease progression well before any clinical manifestations develop. Research and understanding of AD pathology has been driven in recent years by advances in technologies, enabling the precise investigation of the lipidome; the repertoire of lipid species present in cells and tissues that reflect the net effect of gene and protein expression, which in turn are influenced by the cellular environment. Lipidomic studies have identified abnormal lipid metabolism as a key component of the pathological processes which lead to the development of AD. Therefore, lipidomic studies are crucial for advancing the understanding of AD pathology and for identifying potential therapeutic targets; these studies may also facilitate biomarker discovery. Many studies have reported abnormal lipid profiles in both AD plasma and brain tissue. This thesis investigated plasma lipid species using a “shotgun” lipidomics approach by electrospray ionisation tandem mass spectrometry (ESI/MS/MS). Additionally, Phospholipid Transfer Protein (PLTP); a protein involved in lipid metabolism was assayed using a commercial kit. The utility of these analytes as potential AD biomarkers was investigated by testing plasma samples from the highly characterised Australian Imaging, Biomarkers and Lifestyle (AIBL) study. The study cohort comprised over 1000 participants at inception who were classified as either healthy control (n=733), mild cognitive impairment (MCI, n=125) or AD (n=204): Samples from the baseline and 18 month follow-up time points were utilised. Plasma PLTP activity levels were measured in a subset of the baseline samples (n=259). Lipid and PLTP measurements were analysed in conjunction with supplementary neuroimaging and blood biomarker data collected as part of the AIBL study. The thesis identified significant differences in several plasma lipids between clinical classification groups, including several ceramide, sphingomyelin (SM), phosphatidylethanolamine (PE), phosphatidylcholine (PC) and plasmalogen species. Additionally, a panel of lipids was identified which could distinguish AD participants from healthy controls with a sensitivity and specificity of 80%. Plasma PLTP activity was significantly lower in AD and MCI groups compared to healthy controls, and levels correlated with plasma Aβ in all groups and cerebral Aβ in the healthy controls. The results of this thesis validate and extend previous findings reported in the literature. The current findings provide evidence to indicate that several lipid species and PLTP show promise as potential blood biomarkers of AD. Further investigation using a targeted lipidomics platform and prospective longitudinal follow-up is warranted.

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6

Redman, Janet Elaine. "Lipid Biomarkers and the Detection of Ancient Mycobacterial Disease". Thesis, University of Birmingham, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522030.

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Almohmedhusain, Awal. "Lipid associated biomarkers in patients with systemic lupus erythematosus and rheumatoid arthritis". Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/lipid-associated-biomarkers-in-patients-withsystemic-lupus-erythematosus-andrheumatoid-arthritis(e62f01eb-debe-4510-9489-13f05249dbc1).html.

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Patients with chronic inflammatory conditions such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) experience premature cardiovascular mortality and morbidity compared with the general population. The increased risk of cardiovascular disease (CVD) may in part, result from an interaction between traditional and non-traditional risk factors, modulated by chronic inflammation. The aim of this project was to look at lipid associated biomarkers in patients with SLE/RA and the association between these markers and cardiovascular disease outcomes. We also aimed to study the effect of inflammation reduction on vascular biomarkers. In the first study we examined 168 SLE patients median (IQR) age was 53 (46-61) years and median disease duration 13 (7, 23) years and 56 healthy controls median age 50 (39-60) years. We demonstrated elevated level of oxidised-LDLin SLE patients compared with healthy controls (76 (57, 99) U/l vs 56 (42, 88)U/l P= 0.02). We further explored the association between oxidant stress and premature atherosclerosis as measured by carotid intima media thickness (cIMT) and plaque. In addition to age and systolic blood pressure, oxidised-LDL and urinary 8-isoprostane were significantly and independently associated with cIMTin SLE patients _ coefficient 95%CI [0.00007 (5.29−6, 0.0001) and 0.003 (0.0008,0.004)], respectively. In healthy controls, age was the only independent variable. In the Norfolk Arthritis Register, 1266 patients with early inflammatory polyarthritis (IP) were studied. A linear regression analysis revealed a significant negative association between CRP and lipid profile namely TC, LDL, TG and ApoA-1. During a median (IQR) follow up = 5.5 (3.7-7.7) years 100 (7%) patients died (all causes) of which 33% (33) deaths were attributed to CVD. Forward stepwise regression analysis demonstrated that a low total cholesterol was independently associated with all cause mortality HR (95%CI) 0.75 (0.61, 0.91) and CVD mortality HR (95%CI) 0.49 (0.29, 0.85). In a small cohort 27 SLE patients and 15 healthy controls. We measured endothelial function using flow mediated dilatation of the brachial artery. At baseline we found a significant increase in TG level [1.36 (0.9, 1.87) mmol/l vs0.88 (0.64, 1) mmol/l P= 0.009] and a significant impaired endothelial function in SLE patients compared to the healthy controls [2.86 (0.6, 5.3) vs 6.81 (3.46,8.57), P= 0.03]. After treatment, there was a trend towards reduced TG level and improved endothelial function. Oxidised-LDL did not change significantly. In conclusion, oxidant stress is increased in SLE patients and relates to some measures of subclinical atherosclerosis. Control of inflammation may not be sufficient to completely control this in routine practice. In early RA, active inflammationmay mask any tendency to hyperlipidemia in this population. Low total cholesterol may be the best biomarker of the overall metabolic and inflammatory status of the patients as well as indicating a group with increased risk of future mortality.

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8

Duce, Caroline. "Fine scale survey of metals, nutrients and lipid biomarkers in the Conwy Estuary". Thesis, Bangor University, 2018. https://research.bangor.ac.uk/portal/en/theses/fine-scale-survey-of-metals-nutrients-and-lipid-biomarkers-in-the-conwy-estuary(cd62bdc4-20b9-40fa-896e-02db482ca849).html.

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The environmental quality of coastal ecosystems is an issue of growing international attention. Estuarine organic matter is derived from a multitude of natural and anthropogenic allochthonous and autochthonous sources that originate across a freshwater continuum. Various point and diffuse sources, such as discharges of treated and untreated sewage as well as urban and agricultural run-off, contribute significantly to the deterioration of the water and sediment quality of aquatic ecosystems. The EU Water Framework Directive requires all surface waters to fulfil the criterion of “good ecological status” by the end of 2021, this status is defined with reference to undisturbed conditions. Within heavily impacted coastal areas with no prior monitoring of baseline data assessing these reference conditions will be inherently difficult. Understanding near-pristine conditions within estuaries provides reference sites for assessing natural variability of organic and inorganic chemical parameters which in turn will provide baseline conditions for management to allow them to distinguish between changes caused by human and those that are natural. A fine scale survey of metals, nutrients and lipid biomarkers was investigated within an estuary that was perceived to be of relatively pristine condition. The data obtained has been used to assess existing models that aimed to define elevated versus baseline concentrations. The majority of the data focused on the sediment fraction due to its importance as a historic sink of organic and inorganic compounds which in turn enables an understanding of the potential inputs from both natural and anthropogenic sources. Regional geochemical baseline models were constructed for metals and nutrients to enable an understanding whether the organic and inorganic compounds were from natural or anthropogenic origins. The lipid biomarkers were utilised to establish the origin of the organic matter. Within the Conwy estuary there were a number of locations that yielded higher concentrations that were deemed above background levels, these have been discussed to highlight potential sources of contamination. A proportion of locations sampled fell below those that were deemed enriched for metals, nutrients and lipids resulting in concentration ranges of pristine conditions which other contaminated estuaries can refer to.

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9

Pearson, Emma Jane. "Lipid biomarkers in Spanish saline lake sediments : indicators of organic inputs and environmental change". Thesis, University of Newcastle Upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397054.

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Coffinet, Sarah. "Validation and application of lipid biomarkers to reconstruct past environmental changes in East Africa". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066500/document.

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La Province Volcanique du Rungwe (PVR) en Afrique de l’Est abrite diverses archives continentales (séquence de loess-paléosols, tourbières, lacs) permettant d’étudier les changements environnementaux passés des zones tropicales continentales. Ce travail s’est intéressé à l’applicabilité des alkyl tetraéthers de glycérol (tetraéthers) et des n-alcanes comme biomarqueurs de ces changements passés. Leur analyse le long de transects altitudinaux a permis de rendre compte de la capacité des tetraéthers à enregistrer de faibles changements de température de l’air dans la région. En conséquence, une calibration régionale a été établie afin d’améliorer les reconstructions de température de l’air en Afrique de l’Est. Au contraire, il est apparu que la composition isotopique de l’hydrogène des n-alcanes (δ²Hwax) était impactée par des paramètres physiques et biologiques supplémentaires ce qui complique son utilisation pour suivre les changements de température à l’échelle régionale. L’étude des variations de ces deux biomarqueurs le long d’une carotte de tourbe et d’une carotte de sédiment lacustre prélevées dans la PVR a révélé l’existence synchrone d’une période climatique plus chaude au cours de l’Holocène tardif. Par ailleurs, il a été observé dans la carotte de tourbe une transition d’un lac à une tourbière il y a ca. 2000 ans BP. Le présent travail démontre donc que les tetraéthers et les n-alcanes sont des biomarqueurs prometteurs, notamment parce qu’ils sont sensibles à de faibles variation climatiques ; cependant, afin de les interpréter correctement, il est nécessaire d’adopter une approche multi-marqueurs
The Rungwe Volcanic Province (RVP) in East Africa offers a wide diversity of continental archives (loess-paleosols sequences, peatlands, lakes), allowing the investigation of past environmental changes in tropical continents. This work focused on the validation of glycerol dialkyl glycerol tetraether- (GDGT) and n-alkane-derived proxies. Analyses of these two biomarkers along altitudinal transects allowed assessing their ability to record temperature changes in the region. GDGTs were found to be robust temperature proxies in East Africa, and a regional calibration was established to improve temperature reconstructions from soil archives. In contrast, investigation of n-alkane hydrogen isotopic composition (δ²Hwax) in surface soils revealed that its variations seemed to be impacted by additional biological and physical parameters than temperature, preventing its generalization at a regional scale. Application of GDGT and n-alkane proxies to continental archives revealed past environmental changes over the Late Holocene in the RVP. A late Holocene synchronous temperature maximum was especially observed in a peat core and sediment core from two sites of the RVP. A multi-proxy approach was applied to the peat core, revealing that an ecosystem change from a lake to a peatland occurred ca. 2000 yrs BP ago. The present work showed that GDGTs and n-alkanes are promising biomarkers because of their sensitivity to slight climate variations, but that they need to be combined with other proxies to accurately reconstruct environmental changes

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Coffinet, Sarah. "Validation and application of lipid biomarkers to reconstruct past environmental changes in East Africa". Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066500.

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La Province Volcanique du Rungwe (PVR) en Afrique de l’Est abrite diverses archives continentales (séquence de loess-paléosols, tourbières, lacs) permettant d’étudier les changements environnementaux passés des zones tropicales continentales. Ce travail s’est intéressé à l’applicabilité des alkyl tetraéthers de glycérol (tetraéthers) et des n-alcanes comme biomarqueurs de ces changements passés. Leur analyse le long de transects altitudinaux a permis de rendre compte de la capacité des tetraéthers à enregistrer de faibles changements de température de l’air dans la région. En conséquence, une calibration régionale a été établie afin d’améliorer les reconstructions de température de l’air en Afrique de l’Est. Au contraire, il est apparu que la composition isotopique de l’hydrogène des n-alcanes (δ²Hwax) était impactée par des paramètres physiques et biologiques supplémentaires ce qui complique son utilisation pour suivre les changements de température à l’échelle régionale. L’étude des variations de ces deux biomarqueurs le long d’une carotte de tourbe et d’une carotte de sédiment lacustre prélevées dans la PVR a révélé l’existence synchrone d’une période climatique plus chaude au cours de l’Holocène tardif. Par ailleurs, il a été observé dans la carotte de tourbe une transition d’un lac à une tourbière il y a ca. 2000 ans BP. Le présent travail démontre donc que les tetraéthers et les n-alcanes sont des biomarqueurs prometteurs, notamment parce qu’ils sont sensibles à de faibles variation climatiques ; cependant, afin de les interpréter correctement, il est nécessaire d’adopter une approche multi-marqueurs
The Rungwe Volcanic Province (RVP) in East Africa offers a wide diversity of continental archives (loess-paleosols sequences, peatlands, lakes), allowing the investigation of past environmental changes in tropical continents. This work focused on the validation of glycerol dialkyl glycerol tetraether- (GDGT) and n-alkane-derived proxies. Analyses of these two biomarkers along altitudinal transects allowed assessing their ability to record temperature changes in the region. GDGTs were found to be robust temperature proxies in East Africa, and a regional calibration was established to improve temperature reconstructions from soil archives. In contrast, investigation of n-alkane hydrogen isotopic composition (δ²Hwax) in surface soils revealed that its variations seemed to be impacted by additional biological and physical parameters than temperature, preventing its generalization at a regional scale. Application of GDGT and n-alkane proxies to continental archives revealed past environmental changes over the Late Holocene in the RVP. A late Holocene synchronous temperature maximum was especially observed in a peat core and sediment core from two sites of the RVP. A multi-proxy approach was applied to the peat core, revealing that an ecosystem change from a lake to a peatland occurred ca. 2000 yrs BP ago. The present work showed that GDGTs and n-alkanes are promising biomarkers because of their sensitivity to slight climate variations, but that they need to be combined with other proxies to accurately reconstruct environmental changes

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Dias, Isobelle A. "The environmental biogeochemistry of open ocean and partially enclosed marine systems". Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303738.

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13

Claeson, Bohnstedt Kristina. "Determination of biomarkers for lipid peroxidation and oxidative stress : Development of analytical techniques and methods". Doctoral thesis, Stockholm : Department of Analytical Chemistry, Stockholm University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-322.

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14

Andersson, Rina Argelia. "Lipid biomarkers and other geochemical indicators in paleoenvironmental studies of two Arctic systems : a Russian permafrost peatland and marine sediments from the Lomonosov Ridge". Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-65350.

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The reconstruction of past environmental conditions is a fascinating research area that attracts the interest of many individuals in various geological disciplines. Paleoenvironmental reconstruction studies can shed light on the understanding of past climates and are a key to the prediction of future climate changes and their consequences. These studies take on special significance when focused on areas sensitive to climate change. The Arctic region, which is experiencing dramatic changes today in its peatlands and in its ocean, is prime example. The entire region plays a major role in global climate changes and has recently received considerable interest because of the potential feedbacks to climate change and its importance in the global carbon cycle. For a better understanding of the role of Arctic peatlands and the Arctic Ocean to global climate changes, more records of past conditions and changes in the region are needed. This work applies different geochemical proxies, with special emphasis on lipid biomarkers, to the study of a permafrost peat deposit collected from the Eastern European Russian Arctic and a marine core retrieved from the Lomonosov Ridge in the central Arctic Ocean. The results reported of this study show that molecular stratigraphy obtained from the analysis of lipid biomarkers in both peat and marine profiles, combined with other environmental proxies, can contribute significantly to the study of Arctic ecosystems of the past.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.

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15

Al, Moosawi Suzana. "Effect of polyphenols on glucoregulatory biomarkers, blood pressure and lipid profile in overweight and obese subjects". Thesis, Queen Margaret University, 2010. http://etheses.qmu.ac.uk/256/.

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This thesis describes a series of in vitro, animal and humans studies conducted with the aim of investigating the effect of polyphenol-rich green coffee bean extract (GCBE) and dark chocolate (DC) on biomarkers of glucose metabolism, lipid profile and blood pressure (BP) in overweight and obese individuals. Green coffee and Theobroma cacao bean extracts were found to be rich in polyphenols and to act as effective free radical scavenging compounds in vitro. A potential role for GCBE in inhibiting pancreatic lipase was identified in vitro. Preliminary human studies revealed a differential effect of GCBE and DC on fasting glucose, total cholesterol, BP and urinary glucocorticoids. Accordingly, consumption of 200mg GCBE containing 90mg chlorogenic acid (CGA) twice daily for 14 days by healthy overweight and obese volunteers reduced systolic BP (P=0.043), urinary free cortisone (P=0.0015) and waist circumference (-0.78cm; P=0.013) but raised salivary cortisone (P=0.042) without significantly affecting capillary fasting glucose, total cholesterol or urinary antioxidant excretion (P>0.05). The ability of CGA to differentially regulate cortisol metabolism was further highlighted in male C57BL6 mice wherein daily administration of a diet containing 0.15% CGA for 17 days marginally increased cortisol in kidney (P=0.108; eta2=0.26) and reduced hepatic cortisol (P=0.219; eta2=0.14). In the preliminary single-blind randomised cross-over DC study, 2-week consumption of 20g DC containing 500mg or 1000mg polyphenols by overweight and obese individuals produced equal reductions in capillary fasting glucose, systolic and diastolic BP. This was further confirmed by the long-term placebo-controlled trial wherein ingestion of 20g DC (500mg polyphenols) for 4 weeks reduced fasting glucose (P=0.028), insulin resistance (P=0.005), systolic (P=0.020), diastolic BP (P=0.008) and improved insulin sensitivity (QUICKI, P=0.04; revised-QUICKI, P=0.026) and urinary antioxidant capacity (total phenolics, P=0.046; ferric-reducing capacity, P=0.048) without significantly affecting lipid profile (P>0.05). A particular contribution of the main study is the finding that overweight and obese individuals respond more effectively to polyphenol-rich DC, compared to lean individuals, but more adversely to polyphenol-deficient placebo. The latter was marked by the rise in fasting insulin, insulin resistance and salivary cortisol. In conclusion, this thesis supports a role for polyphenol-rich GCBE and DC in counteracting overweight and obesity-related complications. The role of GCBE and CGA in modulating glucocorticoid metabolism emerges as a novel and potentially relevant field of research to the prevention of overweight and obesity-related complications.

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ARIAS, JESICA PAOLA RADA. "NATURAL AND ANTHROPOGENIC ORGANIC MATTER IN SEDIMENTS IN RIA DE AVEIRO, PORTUGAL: CHARACTERIZATION BY LIPID BIOMARKERS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33663@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
BOLSA NOTA 10
A matéria orgânica (MO) sedimentar de origem natural na Ria de Aveiro e no estuário Mondego foi caracterizada usando a composição elementar (C e N) e lipídios biomarcadores (esteróis, n-álcoois e triterpenoides). A contribuição por esgotos foi avaliada através de coprostanol e outros esteróis fecais. Amostras de sedimento superficial foram coletadas em 22 estações ao longo das regiões. Os lipídios biomarcadores foram extraídos, purificação com sílica-gel e analisados por cromatografia em fase gasosa acoplada a espectrometria de massas. O carbono orgânico total (9,94 e 43,00 mg g(-1)) teve uma correlação com o nitrogênio total (r(2) = 0,86). A razão C/N molar (14,34 mais ou menos 1,75) foi um valor típico de MO continental. Existe uma contribuição maior de MO terrestre nas amostras, como mostra as evidencias: a predominância de n-álcoois de cadeia longa (maior ou igual à C22), maior abundancia no somatório de sitosterol, estigmasterol e campesterol sobre outros fitoesterois, como o colesterol e o brassicasterol; e a alta concentração de triterpenoides de plantas superiores, como Beta-amirina e a Alfa amirina. A concentração de coprostanol (0,05 a 16,6 microgramas g(-1)) indicou a presença de esgotos em sete estações localizadas no largo do Laranjo (S4, S5, S6, S7, S10), porto de Aveiro (S14) e no canal de Ílhavo (S16). Os aportes mais significativos foram no largo do Laranjo (S8 e S9) e no porto do Mondego (S19).
The sedimentary organic matter (OM) of natural origin in the Ria de Aveiro and the estuary of Mondego River was characterized using elemental composition (C and N) and lipid biomarkers (sterols, alcohols and triterpenoids). In addition, the contribution by sewage was evaluated by coprostanol and other fecal sterols. Surface sediment samples were collected at 22 stations along the two regions. The lipid biomarkers was extracted, separated with silica-gel and analyzed by gas chromatography coupled to mass spectrometry. Concentrations of total organic carbon (9.94 and 43.00 mg g(-1)) was highly correlated with total nitrogen (r(2) = 0.86). The C/N molar ratio: 14,34 plus-minus 1,75 are typical values of OM of continental origin. There is a major contribution of terrestrially OM to the sediments, as suggested by proxies, including: predominance of long-chain (greater-than or equal to C22) alcohols, higher abundance of sitosterol, estigmasterol and campesterol over other phytosterols, like cholesterol and brassicasterol, and elevated concentrations of triterpenoids from higher plants, as Beta-amyrin and Alpha-amyrin. The concentrations of coprostanol (0.05 to 16.6 micrograms g(-1)) indicated the presence of sewage in seven stations located in the Largo do Laranjo (S4, S5, S6, S7, S10), Port of Aveiro (S14) and in Ílhavo Channel (S16). The more significant contribution of sewage was identified in the Largo do Laranjo (S8 and S9) and the Port of Mondego (S19).

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Bischoff, Juliane. "Microbial communities and their response to Pleistocene and Holocene climate variabilities in the Russian Arctic". Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6889/.

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The Arctic is considered as a focal region in the ongoing climate change debate. The currently observed and predicted climate warming is particularly pronounced in the high northern latitudes. Rising temperatures in the Arctic cause progressive deepening and duration of permafrost thawing during the arctic summer, creating an ‘active layer’ with high bioavailability of nutrients and labile carbon for microbial consumption. The microbial mineralization of permafrost carbon creates large amounts of greenhouse gases, including carbon dioxide and methane, which can be released to the atmosphere, creating a positive feedback to global warming. However, to date, the microbial communities that drive the overall carbon cycle and specifically methane production in the Arctic are poorly constrained. To assess how these microbial communities will respond to the predicted climate changes, such as an increase in atmospheric and soil temperatures causing increased bioavailability of organic carbon, it is necessary to investigate the current status of this environment, but also how these microbial communities reacted to climate changes in the past. This PhD thesis investigated three records from two different study sites in the Russian Arctic, including permafrost, lake shore and lake deposits from Siberia and Chukotka. A combined stratigraphic approach of microbial and molecular organic geochemical techniques were used to identify and quantify characteristic microbial gene and lipid biomarkers. Based on this data it was possible to characterize and identify the climate response of microbial communities involved in past carbon cycling during the Middle Pleistocene and the Late Pleistocene to Holocene. It is shown that previous warmer periods were associated with an expansion of bacterial and archaeal communities throughout the Russian Arctic, similar to present day conditions. Different from this situation, past glacial and stadial periods experienced a substantial decrease in the abundance of Bacteria and Archaea. This trend can also be confirmed for the community of methanogenic archaea that were highly abundant and diverse during warm and particularly wet conditions. For the terrestrial permafrost, a direct effect of the temperature on the microbial communities is likely. In contrast, it is suggested that the temperature rise in scope of the glacial-interglacial climate variations led to an increase of the primary production in the Arctic lake setting, as can be seen in the corresponding biogenic silica distribution. The availability of this algae-derived carbon is suggested to be a driver for the observed pattern in the microbial abundance. This work demonstrates the effect of climate changes on the community composition of methanogenic archae. Methanosarcina-related species were abundant throughout the Russian Arctic and were able to adapt to changing environmental conditions. In contrast, members of Methanocellales and Methanomicrobiales were not able to adapt to past climate changes. This PhD thesis provides first evidence that past climatic warming led to an increased abundance of microbial communities in the Arctic, closely linked to the cycling of carbon and methane production. With the predicted climate warming, it may, therefore, be anticipated that extensive amounts of microbial communities will develop. Increasing temperatures in the Arctic will affect the temperature sensitive parts of the current microbiological communities, possibly leading to a suppression of cold adapted species and the prevalence of methanogenic archaea that tolerate or adapt to increasing temperatures. These changes in the composition of methanogenic archaea will likely increase the methane production potential of high latitude terrestrial regions, changing the Arctic from a carbon sink to a source.
Die Arktis ist in den gegenwärtigen Diskussionen zum Klimawandel von besonderem Interesse. Die derzeitig beobachtete globale Erwärmung ist in den hohen nördlichen Breiten besonders ausgeprägt. Dies führt dazu, dass ehemals gefrorene Böden zunehmend tiefer auftauen und daher im Boden enthaltene Kohlenstoffquellen für die mikrobielle Umsetzung und Mineralisierung zur Verfügung stehen. Aufgrund dieser Prozesse entstehen klimarelevant Gase, darunter Kohlendioxid und Methan, die aus den Böden und Sedimenten freigesetzt werden können. Wenn man bedenkt, dass in den nördlichen Permafrostgebieten die Hälfte des weltweit unter der Bodenoberfläche gelagerten Kohlenstoffs gelagert ist, wird die Bedeutung dieser Region für das Verständnis des globalen Kohlenstoffkreislaufes und der möglichen Treibhaus-gasemissionen sichtbar. Trotz dieser Relevanz, sind die am Kohlenstoffumsatz beteiligten Mikroorganismen in der Arktis wenig untersucht und ihre Anpassungsfähigkeit an die gegenwärtigen Klimaveränderungen unbekannt. Die vorliegende Arbeit untersucht daher, wie sich Klimaveränderungen in der Vergangenheit auf die Anzahl und Zusammensetzung der mikrobiellen Gemeinschaften ausgewirkt haben. Dabei liegt ein besonderer Fokus auf die methanbildenden Archaeen, um das Verständnis der mikrobiellen Methandynamik zu vertiefen. Im Rahmen dieser Arbeit wurden drei Bohrkerne aus zwei verschiedenen Standorten in der russischen Arktis untersucht, darunter terrestrischer Permafrost und Seesedimente aus Sibirien und Chukotka, Russland. Mittels der Identifikation und Quantifizierung von mikrobiellen Genen und charakteristischen Bestandteilen der mikrobiellen Zellmembran war es möglich, fossile mikrobielle Gemeinschaften in Seesedimenten mit einem Alter von bis zu 480 000 Jahren und in Permafrostablagerungen mit einem Alter von bis zu 42 000 Jahren zu rekonstruieren. Es wurde gezeigt, dass es während vergangener warmen Perioden zu einem Wachstum von Bakterien und Archaeen in allen untersuchten Standorten gekommen ist. Dieser Trend konnte auch für die Gemeinschaft der methanogenen Archaeen gezeigt werden, die während warmen und insbesondere feuchten Klimabedingungen in großer Anzahl und Diversität vorhanden waren, was wiederrum Rückschlüsse auf mögliche Methanemissionen erlaubt. In den terrestrischen Permafroststandorten wird der Temperaturanstieg als direkte Ursache für die gefundene Reaktion der mikrobiellen Gemeinschaft vermutet. Im Gegenzug dazu, führte der Temperaturanstieg im untersuchten arktischen See wahrscheinlich zu einer erhöhten Primärproduktion von organischem Kohlenstoff, die wiederum das Wachstum der Mikroorganismen antrieb. Weiterhin konnte im Rahmen dieser Arbeit gezeigt werden, dass Methanosarcina-verwandte Spezies in der Russischen Arktis weit verbreitet sind und sich an veränderte Umweltbedingungen gut anpassen können. Im Gegensatz dazu stehen Vertreter von Methanocellales und Methano-microbiales, die nicht in der Lage sich an veränderte Lebensbedingungen anzupassen. Im Rahmen dieser Arbeit konnte erstmalig gezeigt werden, dass es in früheren Warmphasen zu einem vermehrten Wachstum der an der Umsetzung des organischen Kohlenstoffs beteiligten Mikroorganismen in der Russischen Arktis gekommen ist. Im Zusammenhang mit der zukünftigen Erwärmung der Arktis kann also von einer Veränderung der am Kohlenstoffkreislauf beteiligten Mikroorganismen ausgegangen werden kann. Mit den steigenden Temperaturen werden sich einige Vertreter der methanproduzierenden Mikroorganismen an die veränderten Bedingungen anpassen können, während Temperatur-empfindliche Vertreter aus dem Habitat verdrängt werden. Diese Veränderungen in der mikrobiellen Gemeinschaft können die Methanproduktion der hohen noerdlichen Breiten erhoehen und dazu beitragen, dass aus der Arktis als eine Kohlenstoffsenke eine Kohlenstoffquelle wird.

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Wang, Danlei. "The Study of Lipid Biomarkers and Contemporary Microbial Communities in Early-Eocene Sedimentary Records at Chicxulub Impact Crater". Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/88434.

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This thesis employed comprehensive analytical techniques, including organic geochemistry and molecular microbial ecology, to investigate sedimentary lipid biomarker records and contemporary microbial communities recovered from an early Eocene interval in the Chicxulub impact crater, Gulf of Mexico. This study provided 1) indirect evidence for the possibility of lipid biomarker biodegradation during refrigerated storage of sediment cores from the deep subsurface biosphere and 2) highly-resolved lipid biomarker evidence revealing orbital controls on paleoenvironmental and microbial communities during the end of the EECO.

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Neupane, Prabhat Chandra. "Paleohydrology and Paleoecology of the Neogene Siwalik rocks, Nepalese Himalaya using multi-proxy lipid biomarker isotopic study". ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2348.

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This study deploys compound-specific multi-proxy isotopic study of lipid biomarkers to understand Neogene climatic and ecological variabilities in the Himalayan foreland. The investigation of compound-specific carbon and hydrogen isotopes along with glycerol dialkyl glycerol tetraether (GDGT) is the first of its kind for the Nepalese Siwalik. A total of 49 mudstone (and some paleosol) samples were collected from the paleomagnetically age-constrained Siwalik strata in the Surai Khola and Karnali River sections. δ13C results suggest a domination of C3 trees between 12 and 8.5 Ma, and a stepwise expansion of C4 grasses starting gradually at 8.5 Ma and culminating rapidly around 5.5 Ma. δD results show an overall gradual increase in rainfall since 12 Ma, with a rapid intensification around 5.5 Ma. The negative correlation between rainfall and GDGT-derived paleotemperature prior to 5.5 Ma indicates that the region experienced higher rainfalls during colder periods and vice versa. We propose that this negative correlation could be related to the strong presence of mid-latitude westerlies in the region because of the subdued Himalayas, when summer monsoon winds were weaker, that brought enhanced winter-precipitation particularly during colder periods. After 5.5 Ma, our data show a conspicuous positive correlation between rainfall and annual temperature, indicating the onset of modern-style seasonality in rainfall in the Indian subcontinent, which generates more rainfall during summer than during winter. Notably, this initiation of the Indian monsoon around 5.5 Ma favored the dominance of C4 grasses over C3 trees that is reflected in our δ13C data.

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Gorityala, Shashank. "TARGETED AND UNTARGETED OMICS FOR DISEASE BIOMARKERS USING LC-MS". Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1547093694357568.

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Sousa, Bebiana Costa. "Lipid profile alteration of cells and exosomes in acute myocardial infarction". Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14885.

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Mestrado em Bioquímica - Bioquímica Clínica
Cardiovascular Diseases are the most significant cause of death. Myocardium infarction is one of the most common of this type of diseases and it is characterized by myocardium ischemia. Ischemia occurs in consequence of simultaneous starvation and hypoxia. While ischemia represents a cellular damage, starvation is associated with a cardioprotective effect. The cell response to this injury includes either autophagy or apoptosis depending on the ability to adapt and respond to the injury and is very important for the evolution and recovery of the myocardium infarction. Autophagy is a selfdegradative process that allows cell to adapt to stress and so it is associated with cell survival. The exosomes release by cardiomyocytes is also an adaptive process which functions are related with intercellular communication. On the other hand, apoptosis is a process of programmed cell death. It is well known that lipids play an important role in cardiovascular disease although their role is not completely understood. Lipids are the major component of a cell membrane and play structural and signaling roles. Under several physiopathological conditions, the cell and exosomes lipid content can be modified. However reports on lipidome of cardiomyocytes under cardiovascular diseases are scarce. Thus, the primary aim of this work is to identify lipid profile changes in cardiomyocytes and exosomes released by them under starvation and ischemia, in order to better understand myocardial infarction and if possible to recognize new biomarkers for myocardial infarction. Cardiac cells showed that molecular species alterations in phosphatidylcholine (PC34:1 and PC36:2), phosphatidylethanolamine (PE34:1), phosphatidylserine (PS36:1), phosphatidylinositol (PI36:2, PI38:3 and PI38:5) and sphingomyelin (SM34:1) were changed in ischemia and in starvation in comparison with control group. Some differences were specific of starvation as the decrease in SM(34:1) and the increase in PS(36:1) while apoptosis, autophagy, biomarkers, cardiomyocytes, cardiovascular diseases, exosomes, ischemia, lipidomics, mass spectrometry, myocardial infarction, phospholipids, starvation others were specific of ischemia as the decrease in PC(36:2) and LPC(16:0). The molecular specie PC(34:1) showed different alterations in each condition increasing in case of ischemia and decreasing in case of starvation. For exosomes, our results showed a deviation between the lipidome of exosomes released upon ischemia and starvation for all lipid classes. Some differences matched the ones observed in cells, for example the decrease in PC(34:1) in starvation, but others were different. Since we have only performed lipidomic analysis for a smaller sample of exosomes, it requires further studies to validate the results. In conclusion, ischemia and starvation induced changes in lipid homeostasis. Our work suggests that lipids are potential tools for evaluation of cell fate, either cell death or recovery, that will be useful to improve diagnosis and prognostic of cardiovascular diseases.
As doenças cardiovasculares são a principal causa de morte em todo o mundo. De entre estas, o enfarte do miocárdio é uma das doenças mais comuns, sendo caracterizado por isquemia que leva a morte de células cardíacas. A isquemia ocorre em consequência da privação simultânea de nutrientes e oxigénio. Enquanto a isquemia representa um dano celular, a privação de nutrientes está relacionada com efeitos cardioprotetores. A resposta das células a estes estímulos pode ser por indução de autofagia ou de apoptose, dependendo da sua capacidade de adaptação e resposta aos fatores indutores de isquemia. A autofagia é um processo auto-degradativo que permite à célula adaptar-se ao stresse e é, portanto, um processo associado à sobrevivência celular. A libertação de exossomas pelas células é também um mecanismo de adaptação cujas funções estão relacionadas com a comunicação intercelular. Por outro lado, a apoptose é um processo de morte celular programada. A regulação destes processos é de extrema importância para a sobrevivência e recuperação nos episódios de enfarte do miocárdio. Hoje em dia sabe-se que os lípidos têm um papel importante no desenvolvimento de doenças cardiovasculares embora o seu papel ainda não esteja completamente esclarecido. Os lípidos são os componentes maioritários da membrana celular e desempenham funções a nível estrutural e de sinalização. Quando exposto a diversas condições fisiopatológicas, o conteúdo lipídico das células e dos exossomas é modificado. No entanto, existem ainda poucas publicações sobre a avaliação do lipidoma de cardiomiócitos em patologias cardiovasculares. Assim, o objetivo principal deste trabalho é identificar alterações no perfil lipídico de cardiomiócitos e exossomas libertados por estes sob privação de nutrientes e de oxigénio, de forma a melhor compreender o enfarte do miocárdio e se possível identificar novos biomarcadores para esta patologia. apoptose, autofagia, biomarcadores, cardiomiócitos, doenças cardiovasculares, espectrometria de massa, exossomas, fosfolípidos, infarte do miocárdio, isquémia, lipidómica Nas células cardíacas verificamos que algumas espécies moleculares de fosfatidilcolina (PC34:1 e PC36:2), fosfatidiletanolamina (PE34:1), fosfatidilserina (PS36:1), fosfatidilinositol (PI36:2, PI38:3 e PI38:5) e esfingomielina (SM34:1) variam em isquemia e em privação de nutrientes em comparação com o controlo. Algumas variações foram específicas da privação de nutrientes como a diminuição de SM(34:1) e o aumento de PS(36:1) e outras foram específicas da isquemia como a diminuição de PC(36:2) e de LPC(16:0). A espécie molecular PC(34:1) foi a que se mostrou alterada de forma diferente em cada condição sendo que aumenta em caso de isquemia e diminui em caso da privação de nutrientes. No caso dos exossomas, os resultados obtidos permitiram verificar que houve um maior desvio entre o lipidoma de exossomas libertado em isquemia e privação de nutrientes em todas as classes de lípidos. Algumas alterações foram coincidentes com as observadas para as células, por exemplo a diminuição PC(34:1) em starvation mas outras foram diferentes. Uma vez que apenas se realizaram análises lipdómicas para uma dimensão reduzida de amostra de exossomas, serão necessários estudos futuros para a validação dos resultados obtidos. Em conclusão, a privação de nutrientes e a isquemia induzem alterações na homeostasia dos lípidos. Este trabalho sugere que os lípidos são potenciais ferramentas para avaliar se os cardiomiócitos estão a optar pela morte celular ou pela recuperação, que serão úteis para melhorar o diagnóstico e prognóstico de doenças cardiovasculares.

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Newell, Sarah D. "An analysis of compound specific carbon isotopes of lipid biomarkers a proxy for paleoenvironmental change in the Maya lowlands of Peten, Guatemala /". [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009584.

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[Verfasser], Hockun, Enno [Akademischer Betreuer] Schefuß, Gesine [Gutachter] Mollenhauer i Bernhard [Gutachter] Diekmann. "Southern Patagonian climate the last 51,000 years : Insights from lipid biomarkers and their isotopes / Hockun ; Gutachter: Gesine Mollenhauer, Bernhard Diekmann ; Betreuer: Enno Schefuß". Bremen : Staats- und Universitätsbibliothek Bremen, 2017. http://d-nb.info/1151636371/34.

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Asomaning, Margaret. "Impact of a Wellness Clinic Visit on Cardiovascular Risk Biomarkers in Employees of a VA Medical Center". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3713.

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Background: Worksite screening programs are increasingly being provided by employers as a means to reduce cardiovascular risk in employees. A screening program that consists of fasting serum analysis of glucose plus a lipid panel is offered yearly to employees at the VA medical center in Tampa. A retrospective study was conducted to determine if a wellness clinic exposure resulted in significant changes in employees' markers of cardiovascular risk. Methods: Computerized records were used to follow serial outcomes for glucose, triglycerides, HDL cholesterol, and LDL cholesterol in employees whose screening results showed abnormal levels of one or more of these markers. An intervention group with 66 subjects received a wellness clinic visit including a health risk assessment and education for lifestyle change, and a reference group with 109 subjects received only serum analysis. Outcomes at repeat screening were compared for the two groups. Results: Both groups showed improvement in cardiovascular risk. In the intervention group there was significant intra-subject improvement from baseline for all markers except glucose. For triglycerides and LDL cholesterol there was a significantly greater proportion of subjects who improved in the intervention group. In addition, the improvement for triglycerides was significantly better in the intervention group. Conclusions: This investigation confirms the value of a worksite wellness program in reducing cardiovascular risk in the population studied. A differential impact of age and gender was seen for glucose and triglycerides and indicates that such modifiers should be considered through covariate analysis in assessing wellness program effectiveness. Increasing levels of employee wellness participation to targets identified in this study and adding a health risk assessment for everyone screened will help to identify the specific benefits of the face to face wellness counseling intervention.

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Häggi, Christoph [Verfasser], Michael [Akademischer Betreuer] [Gutachter] Schulz i Boris [Gutachter] Jansen. "Using Lipid Biomarkers and their Isotopic Composition to reconstruct the Late Pleistocene Paleoclimate of the Amazon Basin / Christoph Häggi ; Gutachter: Michael Schulz, Boris Jansen ; Betreuer: Michael Schulz". Bremen : Staats- und Universitätsbibliothek Bremen, 2017. http://d-nb.info/1129843653/34.

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Mannem, Chandana. "IN-QUEST OF BIOMARKERS FOR ALZHEIMER’S DISEASE AND PHARMACOKINETIC PROFILE OF ANTICANCER AGENTS USING LC-MS IN HUMAN PLASMA". Cleveland State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=csu1579470084334844.

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Monteiro, Marcela Piedade. "Bebida à base de subproduto da uva: efeitos sobre o estresse oxidativo e marcadores de risco de doenças cardiovasculares em mulheres saudáveis". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-02052011-145201/.

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Introdução: Estudos epidemiológicos sugerem que o consumo de vinho, produtos de uva e outros alimentos contendo polifenóis está associado à diminuição do risco de doenças cardiovasculares. Na produção de vinhos e suco de uva são geradas quantidades expressivas de bagaço residual, que é prejudicial ao meio ambiente. Por outro lado, este subproduto possui alto teor de antioxidantes e de fibras. Objetivo: Produzir uma bebida à base de farinha de bagaço de uva proveniente do processamento de suco de uva (FBSU) e avaliar seus efeitos sobre o estresse oxidativo e marcadores de risco para doenças cardiovasculares em mulheres saudáveis. Métodos: A bebida de FBSU e um suco comercial de uva (usado como controle no estudo in vivo) foram avaliados : sensorialmente por escala hedônica de 9 pontos; composição proximal segundo a AOAC; características físico-químicas; compostos fenólicos totais por Folin, capacidade antioxidante: (a) absorbância de oxigênio radical - ORAC, (b) capacidade antioxidante total - TAS, (c) capacidade de sequestrar o radical DPPH e (d) sistema -caroteno/ácido linoléico. Sujeitos: mulheres saudáveis (n=15) foram randomizadas em um estudo clínico crossover, controlado, com quatro períodos de duas semanas de duração. Após washout, forneceu-se bebida de FBSU e suco de uva comercial, intercalados com outro washout. Quantificou-se triglicérides, colesterol total e suas frações, proteína C-reativa, IL-6, TNF- e MCP-1. A LDL foi submetida à oxidação e em seguida medidos os produtos de peroxidação lipídica. TAS e ORAC do plasma foram determinados. Nos eritrócitos, foram analisadas as enzimas antioxidantes superóxido dismutase (SOD), glutationa peroxidase (GSH-Px) e catalase (CAT). Realizou-se o ensaio cometa nos linfócitos. O consumo das voluntárias foi avaliado por diário alimentar de 3 dias durante a intervenção com a bebida de FBSU, com o suco comercial e no washout. Resultados: Produto de FBSU recebeu, em média, nota seis para todos os parâmetros analisados sensorialmente. As notas do suco 7 comercial foram em média sete. A composição proximal em base seca da bebida de FBSU foi 10,1por cento de proteínas, 11,1por cento de lipídios e 76,3por cento de carboidratos. O teor de compostos fenólicos variou de 46,5 a 95,8 g/mg EAG (equivalentes de ácido gálico) nos extratos: aquoso, etanólico e acetônico da bebida de FSBU. Nos extratos do suco comercial, foi de 2,00 a 4,80 g/mg EAG. Extratos da bebida de FBSU apresentaram quantidades de fenólicos significativamente maiores do que os do suco comercial. Nas análises de capacidade antioxidante realizadas, os extratos da bebida de FBSU apresentaram valores significativamente maiores do que aqueles do suco comercial. Nas mulheres, não foi verificada alteração significativa nas concentrações de colesterol total, LDL-c, HDL-c, VLDL-c e triglicérides durante o estudo. Valores de proteína C-reativa, IL-6, TNF- e MCP-1 não apresentaram diferença significativa antes e após as intervenções. Não houve mudança significativa na fase lag time de oxidação do plasma nos momentos estudados. A capacidade antioxidante do plasma só aumentou significativamente no teste ORAC para intervenção com a bebida de FBSU. As atividades das enzimas SOD, GSH-Px e CAT não diferiram significativamente em ambos os grupos. O consumo da bebida de FBSU reduziu o dano oxidativo ao DNA nos linfócitos. A média do consumo alimentar foi estatisticamente igual nos três períodos avaliados. Conclusões: A bebida desenvolvida à base de FBSU foi aceita sensorialmente e apresentou capacidade antioxidante nas análises in vitro. A quantidade de 300 mL/dia desta bebida por 14 dias aumentou significativamente a capacidade antioxidante do plasma, avaliada pelo teste ORAC, e protegeu de danos oxidativos o DNA de linfócitos de mulheres saudáveis. Outros parâmetros de balanço redox e biomarcadores de risco de doenças cardiovasculares não foram influenciados
Introduction: Epidemiological studies suggest that consumption of wine, grape products and other foods containing polyphenols is associated with decreased risk of cardiovascular disease. In the production of wine and grape juice significant amounts of pomace flour are generated, which is harmful to the environment. Moreover, this byproduct is high in antioxidants and fiber. Objectives: To develop a beverage using grape pomace flour (GPF) from grape juice and to evaluate its effect on oxidative stress and inflammatory biomarkers for cardiovascular disease risk in healthy women. Methods: GPF beverage and a commercial grape juice (used as control in the in vivo study) were sensory evaluated using the 9-point hedonic scale and had the proximal composition determined using the AOAC methods; physicochemical characteristics were analysed; total phenolics compound were quantified with the Folin-Ciocalteu reagent; antioxidant capacity was determined by different methods: (a) oxygen radical absorbance capacity assay - ORAC, (b) total antioxidant status - TAS, (c) radical scavenging activity (DPPH) assay, (d) -carotene and linoleic acid system). Fifteen healthy women were randomized in a crossover clinical study, controlled with four periods of two weeks duration. It started with washout, followed by GPF beverage and commercial grape juice, interspersed with another washout. We evaluated triglycerides, total cholesterol and its fractions, C-reactive protein, IL-6, TNF- and MCP-1. The LDL was subjected to oxidation and then measured the lipid peroxidation products. TAS and ORAC of the plasma were determined. In erythrocytes, the antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were analyzed. We carried out the comet assay in lymphocytes. We evaluated the dietary intake of volunteers in three separate stages during the intervention with GPF beverage, with commercial juice and washout. Results GPF beverage received, on average, six points for all sensory parameters evaluated. Commercial juice received, on average, seven points. The proximal composition on a dry matter of GPF beverage was 10.1per cent protein, 11.1per cent lipids and 76.3per cent carbohydrate. The phenolic content ranged from 46.5 to 9 95.8 and from 2.00 to 4.80 g/mg GAE (gallic acid equivalents) in aqueous, ethanol and acetone extracts of GPF beverage and commercial juice, respectively. Extracts of GPF beverage showed significantly higher amounts of phenolics than the commercial juice. GPF beverage extracts were significantly better than commercial juice extracts in every antioxidant activity analysis performed. Commercial juice and GPF beverage intake has not altered the amounts of total cholesterol, LDL-C, HDL-C, VLDL-C and triglycerides during the study. Values of C-reactive protein, IL-6, TNF- and MCP-1 showed no significant difference before and after the intervention with commercial juice and GPF beverage. There was no significant change in the lag phase of plasma oxidation. The plasma antioxidant capacity differed significantly only in the ORAC assay for intervention with the GPF beverage. SOD, CAT and GSH-Px activities did not differ significantly in both groups. The consumption of GPF beverage reduced oxidative DNA damage in lymphocytes. The average food consumption was statistically similar in all three periods. Conclusions: The GPF beverage was sensory accepted and presented significant antioxidant capacity in in vitro assays. The amount of 300 mL/day of this drink for 14 days significantly increased plasma antioxidant capacity, measured by the ORAC assay, and protected from oxidative damage the DNA of lymphocytes of healthy women. Other parameters of redox balance and biomarkers of the risk for cardiovascular disease were not affected

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Mißbach, Helge [Verfasser], Volker [Akademischer Betreuer] Thiel, Volker [Gutachter] Thiel, Walter [Gutachter] Goetz i Francois [Gutachter] Raulin. "Formation and preservation of abiotic organic signatures vs. lipid biomarkers - experimental studies in preparation for the ExoMars 2020 mission / Helge Mißbach ; Gutachter: Volker Thiel, Walter Goetz, Francois Raulin ; Betreuer: Volker Thiel". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1161942319/34.

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Ramalepe, Tshepiso Promise. "Effects of pollution and metazoan parasites on the health and oxidative stress biomarkers of two cyprinid fish species in the Olifants River System, South Afrrica". Thesis, University of Limpopo, 2015. http://hdl.handle.net/10386/1525.

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Thesis (M. Sc. (Zoology)) -- University of Limpopo, 2015
The unprecedented expansion in human population and industry, since the industrial revolution in the late 1700s, has led to increased anthropogenic activities which have indisputably impacted freshwater ecosystems and biological communities therein, including fish. Although this has understandably been the focus, under natural aquatic conditions, no organism is only affected by pollution. Parasites have also been shown in a number of interdisciplinary studies to affect the health of aquatic hosts (amphibians, crustaceans, fish, and mammals). This is illustrated in a number of comprehensive studies the detrimental effects parasites exacerbate when their hosts (fish) are stressed. Therefore, the ability of parasites to interact with anthropogenic stressors, as well as effects they have on the genetic, cellular or tissue level of their host is crucial in conservation and sustaining aquatic biodiversity. As such, the present study examined the combined effects of pollution and metazoan parasites on the health and oxidative stress biomarkers, evaluated for the first time for silver carp, Hypophthalmichthys molitrix (Valenciennes, 1844) and rednose mudfish, Labeo rosae Steindachner, 1894, in one of South Africa’s impacted freshwater ecosystems, Flag Boshielo Dam, Olifants River System, Limpopo Province. Seasonal surveys were conducted from February 2012–January 2013. A total of 111 H. molitrix and 116 L. rosae fish specimens were collected using conventional angling gear, scoop and gill nets with stretched mesh sizes of 30–110 mm. The two selected cyprinid fish species were assessed for oxidative stress biomarkers [Glutathione S-transferase (GST), lipid peroxidation (MDA) and Total Antioxidant Capacity (TAC)] and parasitism of metazoan parasites. Concentrations of biomarkers of oxidative damage and antioxidant defense in the gill and liver tissue were measured to assess how these major organs of the immune system responded to oxidative stress associated with parasitic infections. In addition, water quality analyses were carried out by testing an assay of physico-chemical parameters to establish the level of contamination. Fish health was assessed using the Health Assessment Index (HAI), refined Parasite Index (PI), Inverted Parasite Index (IPI) and Condition Factor (K) protocols. Relative to previous studies at Flag Boshielo Dam, water quality results showed an increase of nutrients, major ions and several metals which may have adverse effects that may comprise fish health; however, this dam remains moderately polluted in a mesotrophic state. The fish health assessment results indicated that H. molitrix was more affected in terms of the necropsy and parasite based assessments (HAI, IPI and K) with mean±SD of 65.68±35.51; 68.29±25; 0.82±0.20, respectively, as compared to 39.14±22.44; 28.79±18.33; 1.17±0.21 for L. rosae during the study. In addition, significantly higher parasitic infections (mean prevalence of infection with any species of parasite = 45.3±0.13) were observed for H. molitrix than L. rosae (12.0±0.05). Furthermore, there was considerable variation in biomarker concentration between highly infected and non-infected fish, for and between each species and tissues with regard to parasite infection, suggesting that the specific functions of each tissue are associated with their susceptibility to oxidative stress, as well as their ability to defend against oxidative damage. These results illustrate that although fish are affected by aquatic contaminants they are to an extent affected by parasites, which may act synergistically on the health of the two fish species. Most importantly, it was suggested that knowledge on the parasites of alien H. molitrix when compared to indigenous L. rosae may give an indication of how adaptive this fish are to new localities as well as expands the information on the rarely studied biology, epizootiology and ecological interactions of these two cyprinid species. Keywords: Health Assessment Index, refined Parasite Index, Inverted Parasite Index, Condition Factor, water quality, lipid peroxidation, Glutathione S-transferase, Total Antioxidant Capacity, Hypophthalmichthys molitrix, Labeo rosae, Flag Boshielo Dam.

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Corrêa, Telma Angelina Faraldo. "Comparação da capacidade antioxidante de torras de café e seus efeitos sobre fatores de risco cardiovascular em indivíduos saudáveis". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-03102012-145708/.

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O café, rico em substâncias bioativas, está entre os maiores contribuintes para a ingestão de antioxidantes em vários países. O tipo de torra dos grãos influencia em sua atividade antioxidante. Estudos indicam que o consumo moderado de café filtrado está envolvido na redução do risco de doenças crônicas não-transmissíveis, geralmente associadas entre si e que se constituem em graves problemas de saúde pública. Entretanto, a literatura não apresenta consenso sobre a ação benéfica do café na redução do risco destas doenças. Objetivos: Comparar a atividade antioxidante de dois graus de torras de café (torra média-clara e média) e seus efeitos sobre biomarcadores de risco cardiovascular em indivíduos saudáveis. Métodos: A caracterização de antioxidantes nas bebidas foi realizada pelas análises de compostos fenólicos totais, perfil de ácidos fenólicos, cafeína, melanoidinas e capacidade antioxidante total - TAC (sequestro do radical DPPH e capacidade de absorbância do radical oxigênio - ORAC). Após 1 semana de washout, vinte voluntários saudáveis (20 a 65 anos) ingeriram café filtrado preparado com torra média-clara ou torra média por 4 semanas e com o outro tipo de torra por mais 4 semanas em um ensaio clínico randomizado do tipo crossover, o qual durou 9 semanas. Lipídeos plasmáticos, lipoproteína (a), homocisteína total, biomarcadores glicêmicos e pressão arterial de 24 horas foram medidos antes do período de intervenção a após a ingestão de cada torra. A atividade antioxidante foi avaliada no plasma e em eritrócitos respectivamente pela TAC (kit Total Antioxidant Status e ORAC) e da atividade das enzimas antioxidantes (superóxido dismutase - SOD, glutationa peroxidase - GPx e catalase - CAT). A capacidade de inibição da peroxidação lipídica foi avaliada no plasma pelas determinações de lipoproteínas de baixa densidade (LDL) oxidadas e 8-isoprostano. Biomarcadores inflamatórios relacionados à disfunção endotelial foram medidos no plasma por imunoensaios. Resultados: Vinte voluntários saudáveis (49,5 + 8,9 anos) foram avaliados. A torra média-clara apresentou maior teor de ácidos clorogênicos (334 mg/150 mL; p < 0,001) e menor teor de cafeína (231 mg/150 mL; p = 0,003) que a torra média (210 mg/150 mL e 244 mg/150 mL, respectivamente). Os teores de melanoidinas foram significamente maiores na torra média (p < 0,001). A TAC não diferiu entre as bebidas. A ingestão de ambas as torras causou aumento nas concentrações de colesterol total e LDL (10 e 12 por cento para a torra média-clara; 12 por cento e 14 por cento para a torra média) (p < 0,05). A ingestão da torra média também aumentou a concentração da lipoproteína de alta densidade (HDL) em 7 por cento (p = 0,003). Houve aumento nos índices de Castelli após o consumo da torra média-clara (5 por cento no índice I; p = 0,01 e de 6 por cento no índice II; p = 0,03). O TAS dos indivíduos aumentou 21 por cento e 26 por cento , respectivamente, após consumo da torra média-clara e média (p < 0,001). Os indivíduos também tiveram aumento de 13 por cento e 13 por cento na atividade da CAT, 52 por cento e 75 por cento na SOD e 62 por cento e 49 por cento na GPx após a ingestão da torra média-clara e torra média (p < 0,001), respectivamente. Ambas as torras aumentaram as concentrações da molécula de adesão celular vascular-1 solúvel (sVCAM-1), sendo 18 por cento para a torra média-clara e 14 por cento para a torra média) (p < 0,05). A concentração de fibrinogênio plasmático aumentou 8 por cento após ingestão da torra média (p = 0,01) e a selectina-E solúvel (sE-selectina) aumentou 12 por cento após a torra média-clara (p = 0,02). Embora o consumo de café tenha elevado os níveis de colesterol total e LDL, não se relacionou à alteração de homocisteína total, lipoproteína (a) e biomarcadores de diabetes e de peroxidação lipídica. Conclusão: O consumo moderado de café filtrado apresentou alguns efeitos maléficos sobre o perfil de risco cardiovascular em indivíduos saudáveis, independente de sua atividade antioxidante
Introduction: Coffee is rich in bioactive substances and it is among the major contributors to the total antioxidant ingestion in several countries. The roasting degree of coffee is important for its antioxidant activity. Studies indicate that the moderate consumption of filtered coffee is involved in the prevention of chronic diseases, which are usually associated and constitute serious problems of public health. However, literature does not present consensus about the beneficial effects of coffee in the prevention of these diseases. Objectives: To compare the antioxidant activity of the two coffee roasts (medium light and medium roast) and their effects on biomarkers of the cardiovascular risk in healthy volunteers. Methods: The antioxidant characterization of the coffee beverages was performed by the total phenolic content analysis, phenolic profile, caffeine, melanoidins and total antioxidant capacity - TAC (DPPH radical scavenging capacity and Oxygen radical absorbance capacity - ORAC assays). After 1-week washout, twenty healthy volunteers (20 to 65 years old) consumed medium light roast or medium roast paperfiltered coffee for 4 weeks and then switched to the other roast for an additional 4 weeks in a randomized crossover trial that lasted 9 weeks. Plasma lipids, lipoprotein (a), total homocysteine, serum glycemic biomarkers, and twenty-four hours blood pressure were measured at baseline and after each intervention. Levels of total antioxidant status (TAS) and ORAC were evaluated in plasma, and antioxidant enzymes activities (superoxide dismutase - SOD, glutathione peroxidase - GPx and catalase - CAT) in erythrocytes. Lipid peroxidation inhibition capacity was determined in plasma by oxidized LDL and 8-isoprostane assays. Endothelial dysfunction-related inflammation biomarkers were measured in plasma by immunoassays. Results: Twenty healthy volunteers (49.5 + 8.9 years) were evaluated. Medium light roast coffee showed higher chlorogenic acids (334 mg/150 mL; p < 0.001) and less caffeine (231 mg/150 mL; p = 0.003) than medium roasting (210 mg/150 mL and 244 mg/150 mL, respectively). Melanoidins were significant higher in medium roast than medium light roast (p < 0.001). There was an increase in the Castelli indexes after medium light roast consumption (5 per cent in the index I; p = 0.01, and 6 per cent in the index II; p = 0.03). No significant differences were observed for TAC between the medium light roast and medium roast. Both roasts increased plasma total cholesterol and LDL concentrations (10 per cent , and 12 per cent for medium light roast; 12 per cent , and 14 per cent for medium roast, respectively) (p < 0.05). Medium roast also increased HDL concentration by 7 per cent (p = 0.003). Compared with baseline, subjects had an increase of 21 per cent and 26 per cent in TAS, 13 per cent and 13 per cent in CAT, 52 per cent and 75 per cent in SOD, and 62 per cent and 49 per cent in GPx after medium light and medium roast consumption (p < 0.001), respectively. Both roasts increased soluble vascular cell adhesion molecule-1 (sVCAM-1) concentrations (18 per cent for medium light roast and 14 per cent for medium roast) (p < 0.05). Plasma fibrinogen concentration increased 8 per cent after medium roast intake (p = 0.01), and soluble E-selectin (sE-selectin) increased 12 per cent after medium light roast intake (p = 0.02). Although coffee beverages have increased total cholesterol and LDL levels, they were not related to elevation in total homocysteine, lipoprotein (a), and biomarkers of diabetes and lipid peroxidation. Conclusion: Moderate paper-filtered coffee consumption may have some undesirable impact on cardiovascular risk in healthy subjects regardless of its antioxidant content.

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Marija, Jelić. "Ispitivanje 8-hidroksi-2-deoksiguanozina, produkata lipidne peroksidacije i aktivnosti antioksidativnih enzima kod prekanceroznih lezija i u karcinomu grlića materice". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110296&source=NDLTD&language=en.

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U organizmu se, pod fiziološkim uslovima, produkuju slobodni radikali. Iako se u organizmu nalaze u veoma niskoj koncentraciji, slobodni radikali mogu ispoljiti toksične efekte. Težeći da spare elektrone, u hemijskoj reakciji oksidacije, dolazi do brzog i nepredvidivog vezivanja za susedne molekule, proteine, lipide, ugljene hidrate i nukleinske kiseline od kojih su sačinjeni strukturni elementi ćelije, pokrećući unutrašnji put apoptoze. Antioksidansi su supstance koje sprečavaju ili značajno smanjuju oksidaciju biomolekula. Oksidativni stres je stanje koje nastaje kada produkcija slobodnih radikala premaši kapacitete antioksidativnih enzima da ih neutrališu. U antioksidativne enzime spadaju: superoksid dismutaza (SOD), katalaza (CAT), glutation peroksidaza (GPx), glutation reduktaza (GR) i glutation-S-transferaza (GST). Lipidna peroksidacija (LP) je proces oksidacije višestruko nezasićenih masnih kiselina od strane slobodnih radikala. Malondialdehid predstavlja biohemijski marker pomoću kog je moguće meriti stepen oksidativnog oštećenja ćelijskih membrana. Oksidativna modifikacija DNK dovodi do promene strukture DNK koje rezultuju genetskim oštećenjima. Najčešće korišćen marker oksidativnog stresa je urinarni 8-hidroksi-2-deoksiguanozin (8-OHdG). Oštećenja proteina, lipida, DNK čine važan osnov mnogih oboljenja kao što su ateroskleroza, neurodegenerativna oboljenja, dijabetes, gojaznost, proces starenja, retinopatija, hronične inflamatorne bolesti i karcinom. Polazeći od hipoteze da su ovi biomolekuli različiti u različitim stadijumima bolesti, oni bi mogli predstavljati prognostički marker proširenosti bolesti. Cilj istraživanja je bio da se ispita da li postoje razlike između kontrolne grupe (zdravih žena), pacijentkinja sa prekanceroznim lezijama na grliću materice (HSIL), pacijentkinja sa lokalno ograničenim (FIGO Ia-Ib) i pacijentkinja sa lokalno uznapredovalim karcinomom grlića materice (IIa-IV) u pokazateljima oštećenja DNK (određivanjem vrednosti 8-OHdG), pokazateljima oksidativnog stresa (određivanjem intenziteta lipidne peroksidacije (TBARS)), pokazateljima antioksidativne odbrane (određivanjem aktivnosti antioksidativnih enzima superoksid dismutaze (SOD), katalaze (CAT), glutation peroksidaze (GPx), glutation reduktaze (GR) i glutation-S-transferaze (GST)). Pored toga, cilj istraživanja je bio da se uporede vrednosti 8-OHdG, proizvoda lipidne peroksidacije (TBARS) i aktivnosti antioksidativnih enzima (SOD, CAT, GST, GPx, GR) unutar grupe pacijentkinja sa lokalno ograničenim karcinomom grlića materice podeljenih u dve podgrupe sa niskim i visokim rizikom u odnosu na relaps bolesti. Takođe, u radu je koreliran nivo 8-OHdG, MDA i antioksidativnih enzima sa relapsom bolesti. Istraživanje je izvedeno na Klinici za operativnu onkologiju, odeljenje za ginekologiju na Institutu za onkologiju Vojvodine, Zavodu za farmaciju Medicinskog fakulteta u Novom Sadu i Zavodu za zdravstvenu zaštitu radnika Novi Sad u periodu od 2013. godine do 2017. godine. Od ispitanica su prikupljani uzorci krvi i urina, pripremljeni na adekvatan način i čuvani na -80° do analiza. Aktivnost enzima antioksidativne zaštite, kao i intenzitet lipidne peroksidacije određivani su spektrofotometrijskim metodama, a koncentracija 8-OhdG određivana je gasnom hromatografijom uz masenu detekciju. Za sprovođenje istraživanja dobijena je saglasnost Etičkog odbora Instituta za onkologiju Vojvodine. Pokazano je da postoje statistički značajne razlike između kontrolne grupe (zdravih žena), pacijentkinja saprekanceroznim lezijama na grliću materice (HSIL), pacijentkinja sa lokalno ograničenim (FIGO Ia-Ib) u odnosu napacijentkinje sa lokalno uznapredovalim karcinomom grlića materice (IIa-IV) u pokazateljima oštećenja DNK (koncentracija 8-OHdG), pokazateljima oksidativnog stresa (intenziteta lipidne peroksidacije (TBARS)), pokazateljima antioksidativne odbrane (aktivnosti antioksidativnih enzima SOD, CAT i GST). Nisu pokazane razlike između ispitivanih grupa u aktivnosti enzima glutation peroksidaze (GPx) i glutation reduktaze (GR). Nisu pronađene razlike u koncentraciji 8-OHdG, proizvoda lipidne peroksidacije (TBARS) i aktivnosti antioksidativnih enzima (SOD, CAT, GST, GPx i GR) unutar grupe pacijentkinja sa lokalno ograničenim karcinomom grlića materice podeljenih u dve podgrupe sa niskim i visokim rizikom u odnosu na relaps bolesti. Aktivnosti CAT i GST bile najbolji prediktori rekurencije bolesti kod definisanih pacijentkinja. Na osnovu aktivnosti ova dva oksidativna enzima, separacija grupe pacijentkinja kod kojih nije došlo do rekurencije bolesti nakon perioda praćenja od ostale dve grupe kod kojih je došlo do rekurencije bolesti je bila moguća. Na osnovu dobijenih rezultata zaključuje se da je moguće koristiti navedene biomarkere kao dijagnostičke markere kod pacijentkinja sa karcinomom grlića materice. Ovi biomolekuli mogu pomoći lakšem svrstavanju pacijentkinja u određene grupe prema stadijumu bolesti, a sledstveno i bržem odabiru odgovarajućeg lečenja. Pored toga, pokazano je da su aktivnosti enzima CAT i GST prediktori rekurencije bolesti kod definisanih grupa pacijentkinja.
Free radicals are produced in our body under physiological conditions. Although in very low concentrations, they can show some toxic effects. While trying to bind electrons, in the chemical reaction of oxidation, they rapidly and unpredictably bind to adjacent molecules- proteins, lipids, carbohydrates and nucleic acids from which the structural elements of the cell are made, triggering the internal pathway of apoptosis. Antioxidants are substances that prevent or significantly reduce the oxidation of biomolecules. Oxidative stress is a condition that occurs when the production of free radicals exceeds the capacity of antioxidant enzymes to neutralize them. The antioxidant enzymes include: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST). Lipid Peroxidation (LP) is the process of oxidation of polyunsaturated fatty acids by free radicals. Malondialdehyde is a biochemical marker by which it is possible to measure the degree of oxidative damage of cell membranes. The oxidative modification of DNA leads to a change in DNA structure that results in genetic damage. The most commonly used marker of oxidative stress is urinary 8-hydroxy-2-deoxiguanosine (8-OHdG). The damage to proteins, lipids and DNA is an important basis for many diseases such as atherosclerosis, neurodegenerative diseases, diabetes, obesity, aging, retinopathy, chronic inflammatory disease and cancer. Starting from the hypothesis that these biomolecules are different at different stages of the disease, they could represent a prognostic marker of the progression of the disease. The aim of the study was to examine whether there were differences between the control group (healthy women), the patients with precancerous lesions on the cervix (HSIL), the patients with early stage cervical cancer (FIGO Ia-Ib) and the patient with locally advanced cervical cancer (IIa - IV) in the indicators of DNA damage (determining the value of 8-OHdG), indicators of oxidative stress (by determining the lipid peroxidation intensity (TBARS)), indicators of antioxidant defense (by determining the activity of antioxidative enzymes of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase GPx), glutathione reductase (GR), and glutathione-S-transferase (GST)). In addition, the aim of the study was to compare the values of 8- OHdG, lipid peroxidation products (TBARS) and the activity of antioxidant enzymes (SOD, CAT, GST, GPx, GR) within the group of patients with early stage cervical cancer divided into two subgroups- with low and high risk in relation to the relapse of the disease. The research was performed at the Clinic for operative oncology, Department of Gynecology at the Institute of Oncology of Vojvodina, Medical Faculty in Novi Sad, Department of Pharmacy and the Institute for Health Care of Novi Sad in the period from 2013 to 2017. Samples of blood and urine of the patients were collected, prepared adequately and stored at -80 ° until the analysis. The activity of the antioxidant enzymes as well as the lipid peroxidation were determined by spectrophotometric methods, and the concentration of 8-OHdG was determined by gas chromatography with mass detection. The approval of the Ethical Committee of the Institute for Oncology of Vojvodina was obtained before conducting the research. It has been shown that there are statistically significant differences between the control group (healthy women), patient with precancerous cervical lesions (HSIL), the patients with early stage cervical cancer (FIGO Ia-Ib) compared to a group of patients with locally advanced cervical cancer (IIa-IV) in indicators of damage to DNA (concentration of 8-OHdG), indicators of oxidative stress (lipid peroxidation (TBARS)), indicators of antioxidant defense (activities of antioxidant enzymes SOD, CAT and GST). There was no difference between the groups in activity of glutathione peroxidase enzyme (GPx) and glutathione reductase (GR). There were no differences in the concentration of 8-OHdG, lipid peroxidation products (TBARS) and the activity of antioxidant enzymes (SOD, CAT, GST, GPx and GR) within the group of patients with locally restricted cervical cancer divided into two subgroups with low and high risk in relation on relapses of the disease. CAT and GST activities were the best predictors of disease recurrence among defined groups. Based on the activities of these two oxidative enzymes, the separation of the group of patients who did not experience disease recurrence after a follow-up period from the other two groups in which recurrence of the disease occurred was possible. Based on the obtained results it is concluded that it is possible to use the studied biomarkers as diagnostic markers in patients with cervical cancer. These biomolecules can help in the patient's classification into certain groups according to the stage of the disease, and consequently the more efficient choice of appropriate treatment. In addition, CAT and GST enzyme activity have been shown to be predictors of disease recurrence in defined patient groups.

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Mohd, Ali Masni. "Multivariate statistical analyses in lipid biomarker studies". Thesis, Bangor University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288132.

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Zhang, Alison Yan. "Biomarkers and Lipids in Localised Prostate Cancer". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20492.

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In practice, despite using existing clinicopathological biomarkers to predict outcomes, many localised prostate cancers are still over-treated. Hence improved markers in localised prostate cancer (PC) are urgently required. The aim of this thesis was to validate potential prognostic markers of localised PC, with an emphasis on zinc-alpha 2-glycoprotein (AZGP1) as a lipid-based biomarker. The thesis also explores the contributions of lipids in PC progression using various pre-clinical platforms. AZGP1 is putative biomarker in PC. Data from our prospective phase III validation study demonstrates that AZGP1 status at radical prostatectomy (RP) is predictive of outcomes. Samples from 347 patients undergoing RP were analysed for AZGP1 expression. Absent/low AZGP1 expression was an independent predictor of shorter metastasis-free survival. AZGP1 also improved the discriminatory value of existing prognostic risk models. Over decades, our research group has also contributed to other studies of molecular biomarkers in PC. These candidate biomarkers have been re-analysed in discovery and validation cohorts to examine for more clinically meaningful endpoints of metastasis and PC death. Out of 12 evaluable markers, AZGP1 and Ki67 were the key predictors of these clinically relevant outcomes. Importantly, this thesis demonstrates that PSA relapse is a poor surrogate for metastasis and death. AZGP1 is a known lipid-mobilising factor. Using an in vitro spheroid model and a novel ex vivo platform, we investigated the relationship between lipids and PC cells. With fatty acid co-culture, we demonstrated that there is gross uptake of fatty acids from the tumour microenvironment. We identified the role of external fatty acid uptake as the dominant component of energy transfer over de novo lipid synthesis from glucose and glutamine utilisation in PC. The resultant lipid uptake led to increased PC growth and proliferation.

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Teece, Mark A. "Biodegradation of algal lipids and significance for sediment studies". Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239071.

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Madureira, Luiz Augusto dos Santos. "Lipids in recent sediments of the eastern North Atlantic". Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238908.

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Cass, Christine J. "A Comparative Study of Eucalanoid Copepods Residing in Different Oxygen Environments in the Eastern Tropical North Pacific: An Emphasis on Physiology and Biochemistry". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3036.

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The eastern tropical north Pacific (ETNP) is characterized by one of the ocean's most severe midwater oxygen minimum zones (OMZs), where oxygen levels are often less than 5 µM. The copepod family Eucalanidae is a numerically abundant and diverse zooplankton group in the ETNP, and displays a wide range of vertical distributions related to environmental oxygen concentrations. The goal of this dissertation was to develop a better understanding of the ecology, physiology, and biochemistry of closely related copepod species (family Eucalanidae) that inhabit the ETNP OMZ system. This was accomplished through examining different parameters relating to (1) metabolic rates, (2) detailed lipid composition and biomarkers, and (3) body composition, enzyme activity and survivorship in low oxygen water. Oxygen consumption, ammonium, urea, and phosphate excretion rates were generally highest in Subeucalanus subtenuis, a copepod primarily residing in the upper euphotic zone. Eucalanus inermis, typically found in the lowest oxygen environment of the species examined, showed significantly lower metabolic rates largely due to high water content. Rhincalanus rostrifrons, residing primarily in the upper oxycline, showed intermediate rates, likely relating to its higher reliance on lipid catabolism than S. subtenuis and E. inermis. Urea excretion rates showed a complicated relationship with temperature and oxygen, which calls for further study. Knowledge of such interactions is necessary for accurate modeling of nitrogen cycles in OMZ and other oceanic regions. Lipid biomarkers suggested that S. subtenuis, E. inermis and Pareucalanus attenuatus all fed primarily on particulates near the chlorophyll maximum region, while R. rostrifrons and R. nasutus likely fed on sinking particulates at depth. These results also emphasized the difference in lipid composition between wax esters and triacylglycerol components of storage lipids. This study suggested a much larger role of phylogeny in characterizing lipid contents than previously thought. Body composition, enzyme assays and survivorship studies suggested that E. inermis, S. subtenuis, P. attenuatus, R. nasutus and R. rostrifrons formed four separate ecological groups based on genus. E. inermis had low organic matter, moderate lactate dehydrogenase (LDH) activity, and high survivorship at oxygen concentrations < 20 µM. Rhincalanus spp. also had moderate LDH activity and high survivorship in low oxygen, but were unique in particularly low protein and high lipid content. S. subtenuis was characterized by high protein content, no measurable LDH activity and low survivorship in < 20 µM O2. P. attenuatus was similar to S. subtenuis in many respects, but had lower protein content and a different lipid accumulation strategy. In conclusion, eucalanoid copepods utilized many different ecological strategies in the ETNP OMZ system. Features of different ecological groups fit well with their observed vertical distributions in the water column. Understanding the ecology of organisms in OMZ systems will allow us better predictive capability for the effects of expanding OMZs in other regions.

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Sliz, E. (Eeva). "Genetics and molecular epidemiology of metabolic syndrome-related traits:focus on metabolic profiling of lipid-lowering therapies and fatty liver, and the role of genetic factors in inflammatory load". Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526222554.

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Abstract Metabolic syndrome is a constellation of metabolic abnormalities predisposing to cardiovascular diseases (CVD), type 2 diabetes, and increased mortality. Due to the high prevalence and severe co-morbidities, metabolic syndrome constitutes a major burden for both public health and the global economy. Improved understanding of the detailed molecular mechanisms could provide novel strategies for the treatment and preferably prevention of the metabolic syndrome-related health issues. Recent advancements in ‘omics’ technologies have facilitated the development of novel tools to examine the links between genetic variation and human health. The new techniques allow determination of millions of genotypes or quantification of hundreds of metabolic measures from a single blood sample. In this thesis, genomics and metabolomics approaches are coupled to improve our understanding of the metabolic syndrome-related health issues. More precisely, my projects evaluate the metabolic effects of two lipid-lowering therapies and non-alcoholic fatty liver, as well as assess genetic determinants of chronic inflammation. The present results indicate generally consistent metabolic effects of statins and proprotein convertase subtilisin/kexin type 9 (PCSK9) genetic inhibition. The subtle discrepancies observed could potentially contribute to differences in the efficacy to lower CVD risk between statins and PCSK9 inhibitors. The dissimilar metabolic effects of the four genetic variants that increase the risk of non-alcoholic fatty liver disease (NAFLD) highlight the heterogeneity of the molecular mechanisms involved in NAFLD pathogenesis. The results further suggest that fatty liver by itself might not promote unfavourable metabolic aberrations associated with fatty liver on a population level. The newly identified loci associating with inflammatory phenotypes elucidate the genetic mechanisms contributing to the inflammatory load. In particular, the present results suggest the important role of the locus determining the ABO blood types in the regulation of the soluble adhesion molecule levels. To conclude, this thesis successfully complements the knowledge of the molecular mechanisms involved in metabolic syndrome-related traits and provides examples of how to couple omics technologies in the study of complex traits or in the evaluation of drug effects
Tiivistelmä Metabolinen oireyhtymä on tila, jossa useiden aineenvaihdunnallisten riskitekijöiden kasautuminen suurentaa riskiä sairastua tyypin 2 diabetekseen ja sydän- ja verisuonitauteihin sekä lisää kokonaiskuolleisuutta. Vakavista liitännäissairauksista ja suuresta esiintyvyydestä johtuen metabolinen oireyhtymä kuormittaa merkittävästi sekä terveydenhuoltoa että kansantaloutta. Jotta metabolisen oireyhtymän hoitoon ja ennaltaehkäisyyn voitaisiin kehittää uusia keinoja, on tärkeää ymmärtää paremmin oireyhtymän syntyyn vaikuttavat täsmälliset molekyylimekanismit. Niin sanottujen ’omiikka-tekniikoiden’ viimeaikainen kehitys tarjoaa uusia mahdollisuuksia tutkia geenimuutosten vaikutuksia terveyteen. Uusien tekniikoiden avulla voidaan määrittää miljoonia genotyyppejä tai satoja aineenvaihdunnan merkkiaineita yhdestä verinäytteestä. Tässä väitöskirjatyössä yhdistetään genomiikan ja metabolomiikan menetelmiä metaboliseen oireyhtymään liittyvien terveysongelmien tutkimiseksi. Väitöskirjani osatöissä arvioin kahden lipidilääkkeen sekä ei-alkoholiperäisen rasvamaksan aineenvaihdunnallisia vaikutuksia sekä pyrin tunnistamaan krooniseen tulehdukseen vaikuttavia geneettisiä tekijöitä. Tulosten mukaan statiinien ja PCSK9:n (engl. proprotein convertase subtilisin/kexin type 9) geneettisen eston aineenvaihduntavaikutukset ovat hyvin samankaltaiset. Kuitenkin havaitut pienet poikkeavuudet tietyissä merkkiaineissa voivat vaikuttaa eroavaisuuksiin siinä, kuinka tehokkaasti lääkeaineet alentavat sydäntautiriskiä. Suuret erot rasvamaksan riskiä lisäävien geenimuutosten vaikutuksissa aineenvaihduntaan korostavat rasvamaksaan liittyvien molekyylimekanismien monimuotoisuutta. Tulosten perusteella vaikuttaa siltä, että rasvan kertyminen maksaan ei luultavasti itsessään aiheuta suuria muutoksia verenkierron aineenvaihduntatuotteiden pitoisuuksiin. Tulehdusmerkkiaineisiin assosioituvat uudet geenialueet täydentävät tulehduksen molekyylimekanismeihin liittyvää tietoa. Tulokset korostavat ABO-veriryhmän määräävän geenin vaikutusta liukoisten adheesiomolekyylien pitoisuuksiin. Kaiken kaikkiaan väitöskirjan osatyöt tuovat uutta tietoa metaboliseen oireyhtymään liittyvien terveysongelmien molekyylimekanismeihin. Projektit havainnollistavat, miten omiikka-tekniikoita voidaan hyödyntää monitekijäisten fenotyyppien tutkimuksessa sekä lääkeaineiden aineenvaihduntavaikutusten arvioinnissa

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Courel, Blandine. "Caractérisation de substances naturelles en contexte archéologique : apport des études moléculaires, isotopiques et de la datation au 14C". Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAF026/document.

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Ces travaux d'archéométrie concernent l’étude moléculaire par GC-MS de marqueurs lipidiques (biomarqueurs) préservés au sein de sols archéologiques et de substances végétales impliquées en tant qu'ingrédients dans la confection d’artefacts. Des analyses complémentaires en isotopie du carbone de composés individuels et des mesures de datation au 14C (AMS MICADAS) de la matière organique totale des sols, d'extraits lipidiques et d'un composé individuel (miliacine) ont également été effectuées. Cette approche a permis:- de montrer l’existence de la culture de millet dès l’âge du Bronze en Alsace, les sols associés à cette culture et leur contenu organique ayant été piégés et préservés dans des silos à grains enterrés datés de l’âge du Fer.- d'identifier la nature de structures archéologiques comme étant d'anciennes latrines et une aire de stabulation de bétail via l'identification de stéroïdes fécaux.- d'établir des critères chimiotaxonomiques fiables basés sur l'analyse des lipides pour l’authentification de résines de styrax et de liquidambars.- d'identifier la nature d'une résine issue de Styrax officinalis ayant été incorporée dans l’enduit organique ornant un crâne décoré (IXème millénaire av. J.-C., site de Nahal Hemar, Israël).- de mettre en évidence l’emploi de brai de bouleau comme agent collant lors de la confection d’un bijou daté du Premier âge du Fer
In this archaeometric study, lipid biomarkers from archaeological soils and organic substances originating from plants found on artefacts were investigated by GC-MS. In addition, the stable carbon isotopic composition of individual lipids and the 14C age (AMS MICADAS) of soil organic matter, lipid extracts and one isolated compound (miliacin) were determined. Such an archaeometric approach allowed:- the existence of a millet cultivation during the Bronze Age in Alsace to be unveiled for the first time based on preserved molecular remains of this cereal in agricultural soils trapped within grain silos dated from the Iron Age.- the function of uncharacterized archaeological structures to be identified as ancient latrines and a stall area based on the identification of faecal steroidal markers.- reliable chemotaxonomic criteria for the authentication of styrax resins and liquidambar gums to be established using specific organic markers (triterpenoids, notably).- the vegetal component of an organic coating decorating a skull from the 9th millennium BC (Nahal Hemar site, Israel) to be identified as a resin from Styrax officinalis.- the use of birch bark tar as adhesive for the making of a jewellery dated from the Iron Age to be discovered

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Mak, Blossom Po Sum. "The role of lipid metabolism in advanced prostate cancer". Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29713.

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In metastatic castration-resistant prostate cancer (mCRPC), elevated plasma sphingolipids and a 3-lipid signature (3LS) are associated with worse clinical outcomes. The thesis aims to: assess the association between 3LS, somatic genetic aberrations and clinical outcomes in mCRPC; determine whether simvastatin therapy modulates the circulating lipidomic profile in men with mCRPC; and characterise the effect of extracellular sphingolipids on prostate cancer cells in vitro. Elevated circulating sphingolipids were found to be associated with AR, TP53, RB1 and PI3K aberrations in mCRPC, which are somatic aberrations linked to poor outcomes. Notably, the combination of lipid and genetic abnormalities conferred a worse prognosis. This suggests that certain genotypes in mCRPC may benefit from metabolic therapies. A proof-of-concept study of simvastatin in addition to standard therapy for mCRPC showed that simvastatin can modulate the circulating lipid profile by reducing plasma sphingolipids. Simvastatin eliminated the 3LS in almost half the men with this poor prognostic biomarker, thus demonstrating its potential as a metabolic targeting strategy. Treatment of prostate cancer cells with plasma from men with mCRPC and the 3LS increased cell viability in vitro. This phenotype was associated with gene expression and lipidomic changes that likely involve the NF-κB, sphingosine-1-phsosphate and sphingomyelin pathways. Therefore, plasma lipids may have a direct effect on prostate cancer growth and be a potential therapeutic target. In conclusion, elevated plasma sphingolipids are associated with worse clinical outcomes in mCRPC, providing prognostic information in addition to established genomic biomarkers. Extracellular sphingolipids increase prostate cancer cell viability, potentially through activation of ceramide metabolism towards pro-survival sphingolipids. This can be therapeutically targeted with simvastatin, which can eliminate the poor prognostic 3LS in men with mCRPC.

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Ricke, Katharine (Katharine Leigh). "Analysis of biomarker candidates from plant lipid inputs into Galapagos lacustrine sediments". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/114319.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2004.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 55-57).
Paleoclimatological investigations into past precipitation and temperature patterns in regions of the tropical Pacific may be the key to resolving scientific disputes about the effects of global warming on the magnitude and frequency of the El Niño/Southern Oscillation (ENSO) phenomenon. Plant lipids identified in the sediment record of lakes in regions of high ENSO activity can act as biomarkers to reconstruct past precipitation patterns by measuring the D/H ratios preserved in these compounds to observe the local climate changes with global temperature variations. Twelve plant species and two sediment samples from in and around El Junco lake catchmernt on Sari Cristobal in the Galapagos Islands were solvent extracted, identified and quantified using gas chromatography arid mass spectrometry. The analysis revealed evidence for significant aquatic and terrestrial vascular plant inputs to lake sediments. High concentrations of unsaturated C₁₆ and C₁₈ fatty acids were found in all plant samples, but these compounds appear to be degraded significantly in the sediment record. n-Alkane distributions suggest a strong hydrocarbon contribution from submerged and floating plants. Additionally, a terrestrial biomarker, fernene, was identified. The information in this study should be a helpful guide for further biomarker identification efforts at the El Junco lake and in other tropical crater lakes.
by Katharine Ricke.
S.B.

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Galper, Jasmin. "Inflammatory and lipid markers in clinical and pre-clinical Parkinson’s disease patients". Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/27967.

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Parkinson’s disease (PD) risk gene discoveries have implicated lipids and inflammation in pathology. However, most research to date has been protein-centric. Therefore, the extent of lipid involvement in PD and relationships between inflammatory and lipid pathways are unclear. Research into these areas may provide novel insights into PD pathology, therapeutic targets and biomarkers for an earlier diagnosis and monitoring disease progression in clinical trials. To investigate lipid dysregulation in PD and in mutation carriers of the PD risk gene LRRK2, untargeted mass spectrometry was performed using serum (N = 221) and cerebrospinal fluid (CSF, N = 88) from controls, pre-clinical and clinical PD LRRK2 G2019S carriers and sporadic PD patients. Findings were then validated in a second cohort (N = 315) using serum from the same groups. Significant lipid alterations were found in mutation carrier and PD patient serum and CSF. Altered lipids implicated sphingolipid metabolism and insulin signalling pathways in PD. Further, altered serum and CSF lipids correlated with cytokines involved in insulin/glucose signalling. Pre-clinical PD biofluid changes suggest that lipids are worthwhile candidates for longitudinal studies assessing whether baseline markers predict PD. Correlation analysis indicated that although serum lipids did not robustly associate with clinical severity, CSF lipids were associated. Finally, whether mutations in the lipid-related risk gene, GBA, affected inflammatory markers was assessed in plasma (N = 371) from clinical and pre-clinical GBA mutation carriers, sporadic PD patients and controls. Inflammatory markers were overall unchanged in GBA mutation carriers, suggesting these are not promising biomarker candidates. These findings strongly support a role for lipid dysregulation in PD. These results indicate that lipids are promising candidates to pursue for understanding PD aetiology, as well as potential novel biomarkers for genetic and sporadic PD.

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Waldron, Elizabeth Louise. "Analysis of urinary lipid biomarker candidates from tuberculosis patients by multiple reaction monitoring". Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/30998.

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Background: Tuberculosis (TB) is an aggressive disease and is the leading cause of death by infectious disease in South Africa. With early diagnosis and correct treatment, almost all TB cases can be cured. The main diagnostic tests in South Africa are limited for people living in rural areas, require sputum which cannot be produced by very ill patients, and have low sensitivity in immune compromised individuals. There is an urgent need for a non-invasive and robust diagnostic test which uses an easily accessible biofluid and can be performed at the point-of-care. Urine has shown promise as a diagnostic biofluid for biomarker investigation. Full scan mass spectrometry is the gold standard for the unbiased discovery of biomarker candidates, and targeted multiple reaction monitoring (MRM) is the method of choice for subsequent validation of biomarker candidates. A list of candidate urinary biomarkers has previously been generated which can discriminate between latent and active TB infection using MS1 mass spectrometry, but these biomarkers have not yet been verified by targeted mass spectrometry. Aims and Objectives: The aim of this project is to verify a list of biomarker candidates using MRM assays by: 1) developing MRM assays for known fatty acid standards, and 2) developing MRM assays for unidentified urinary lipid biomarker candidates de novo, which can be applied to clinical cohorts for future validation. Methods: Fatty acid standards were initially assessed using direct infusion full-scan MS1 mass spectrometry on an orbitrap mass analyser. They were then optimised for fragmentation by compound optimisation on a triple-quadrupole mass analyser, the data from which was used to build MRM assays. Liquid chromatography was optimised for these lipids and the MRMs were validated by spiking the lipid standards into a complex mixture. For the second part of the project, lipid extract (containing unidentified biomarker candidates) from patient derived urine samples were analysed by data-dependent acquisition with inclusion lists on an orbitrap mass analyser. From this experiment MS/MS data was acquired for biomarker candidates which were then compiled into MRM assays and verified using a triple-quadrupole mass analyser. Results: From six fatty acid standards, reliable MRM assays were generated for five of them. The biomarker candidates formed a list of 70 molecules which were further refined to 10 molecules which were reproducibly measured by MRM assay. Discussion and Conclusions: From this work the fatty acid standards can be used as internal retention time predictors for future lipidomic work and quality checks, as they eluted across a wide retention time range. The biomarker candidates have been verified using MRM assays and can be validated in larger clinical cohorts in the future. The end-goal is to use these biomarker candidates as part of a panel which represents a unique biosignature according to the disease state of the patient.

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Ålander, Lovisa. "Evaluation of lipid bromination : For the relative measurement of a chlorine gas biomarker". Thesis, Umeå universitet, Kemiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184523.

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Novack, Mariana Moura Ercolani. "Efeito da sazonalidade e do tratamento térmico industrial no perfil de ácidos graxos do leite e resposta biológica de ratos com diferentes fontes lipídicas". Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/3398.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
There is a great concern of consumers with health, food safety and nutritional value of foods that come with even more interest in sau-hum- ming, nutritious and great use food products. Aimed to evaluate the effect of seasonality and industrial heat treatment on fatty acids of milk and the biological response of rats on diets of different lipid sources submitted or not to physical activity profile. In assessing the effect of climate station and heat treatment on fatty acid profile of milk samples were collected (in natura, pasteurized and sterilized) for 11 consecutive months in the Rio Grande do Sul Dairy Industry. Samples were subjected to extraction lipids and after the determination of fatty acid profiles in gas chromatography, using patterns of fatty acids. The bioassay was conducted for a period of 52 days, we used 36 adult male Wistar rats, divided into 6 treatments of six animals each and were fed diet AIN- 93M, varying the source of lipids and regular physical activity: DCSA normolipídica control, with soybean oil and no physical activity; DCCA normolipídica control with soy oil and physical activity; DMSA fat with butter and no physical activity; DMCA fat with butter and physical activity; DGSA fat with hydrogenated vegetable fat and no physical activity; DGCA fat diet with hydrogenated vegetable fat and physical activity. We investigated the effect of treatments on feed intake, weight gain, feed conversion, feed efficiency ratio, weight, liver, kidneys, heart, epididymal fat digestibility of diets, blood parameters (total COL, HDL, TG, GLI , ALB, ALT, AST, urea, creatinine, IL-1, IL-6, IL-10, TNF-α, IFN-γ and PCRus) and the histology of the aortic arch. The sterilization of milk caused reduction of docosanoic fatty acids, conjugated linoleic acid (cis-9, trans-11) and eicosapentaenoic ratio PUFA: SFA. The seasonal variation caused in octadecatrienoic fatty acids, conjugated linoleic acid (cis- 9, trans-11), docosadienoic acid, and eicosapentaenoic ratio PUFA: SFA. The experimental diets interfere with the feed intake, weight gain, feed conversion ratio, feed efficiency coefficient, epididymal fat weight and total cholesterol blood parameters, alanine transaminase, aspartate transaminase, IL-1, IL-6 and IL-10. Physical activity influence on blood triglyceride, creatinine, IL-1, IL-6 and IL-10. The interaction between diet and physical activity was significant for TNF-α and INF-γ. From the results it can be concluded that the heat-treated milk (pasteurization and sterilization) produced in four seasons show variations in the fatty acid profile. The concomitant fat diet with regular physical activity promotes normal development and maintenance of experimental animals.
Existe uma grande preocupação dos consumidores com a saúde, segurança alimentar e valor nutricional dos alimentos com isso surgem interesse por produtos alimentícios ainda mais saudáveis, nutritivos e de grande aproveitamento. Objetivou-se avaliar o efeito da sazonalidade e do tratamento térmico industrial no perfil de ácidos graxos do leite e a resposta biológica de ratos com dietas de diferentes fontes lipídicas submetidos ou não à atividade física. Na avaliação do efeito da estação climática e do tratamento térmico no perfil de ácidos graxos, foram coletadas amostras de leite (in natura, pasteurizado e esterilizado) durante 11 meses consecutivos em Indústria de Laticínios do Rio Grande do Sul. As amostras foram submetidas a extração de lipídios e após a determinação do perfil de ácidos graxos em cromatografia gasosa, empregando-se padrões de ácidos graxos. O ensaio biológico foi conduzido por um período de 52 dias, utilizou-se 36 ratos Wistar machos adultos, distribuídos em 6 tratamentos de 6 animais cada, que receberam ração AIN-93M, variando a fonte de lipídeos e a prática regular de atividade física: DCSA controle normolipídica, com óleo de soja e sem atividade física; DCCA controle normolipídica, com de óleo de soja e com atividade física; DMSA hiperlipídica, com manteiga e sem atividade física; DMCA hiperlipídica, com manteiga e com atividade física; DGSA hiperlipídica, com gordura vegetal hidrogenada e sem atividade física; DGCA dieta hiperlipídica, com gordura vegetal hidrogenada e com atividade física. Investigou-se o efeito dos tratamentos sobre o consumo de ração, ganho de peso, conversão alimentar, coeficiente de eficiência alimentar, peso fígado, rins, coração, gordura epididimal, digestibilidade das dietas, parâmetros sanguíneos (COL total, HDL, TG, GLI, ALB, ALT, AST, uréia, creatinina, IL-1, IL-6, IL-10, TNF-α, IFN-γ e PCRus), bem como a histologia do arco aórtico. A esterilização do leite ocasionou diminuição dos ácidos graxos docosanóico, linoléico conjugado (cis-9, trans-11), eicosapentanóico e na relação PUFA:SFA. A sazonalidade causou variação nos ácidos graxos octadecatrienóico, linoléico conjugado (cis-9, trans-11), docosadienóico, eicosapentaenóico e relação PUFA:SFA. As dietas experimentais interferiram no consumo alimentar, ganho de peso, conversão alimentar, coeficiente de eficiência alimentar, peso da gordura epididimal e nos parâmetros sanguíneos de colesterol total, alanina transaminase, aspartato transaminase, IL-1, IL-6 e IL-10. A atividade física influenciou nas concentrações sanguíneas de triglicerídeos, creatinina, IL-1, IL-6 e IL-10. A interação entre dieta e atividade física foi significativa para TNF-α e INF-γ. Através dos resultados pode-se concluir que os leites submetidos a tratamentos térmicos (pasteurização e esterilização) produzidos nas quatro estações do ano apresentam variações no perfil de ácidos graxos. As dietas hiperlípidica concomitante com a prática regular de atividade física promovem a manutenção e desenvolvimento normal dos animais experimentais.

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CAPUZZI, ENRICO. "RECENT SUICIDE ATTEMPTS AND SERUM LIPID PROFILE IN SUBJECTS WITH MENTAL DISORDERS: A CROSS-SECTIONAL STUDY". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241289.

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Introduzione: I soggetti con disturbi mentali hanno un rischio più elevato di comportamenti suicidari rispetto alla popolazione generale. Pertanto, ad oggi, i ricercatori hanno studiato alcuni marcatori biologici potenzialmente correlati al suicidio. Nonostante molti studi abbiano riportato una possibile correlazione tra bassi livelli ematici di lipidi e tentativo di suicidio, sono emersi risultati contrastanti. Scopo del lavoro: Abbiamo studiato se il colesterolo totale , il colesterolo LDL e i trigliceridi ematici siano associati a recenti tentativi di suicidio in soggetti con diversi disturbi mentali. Metodi: Abbiamo condotto uno studio trasversale su 593 pazienti ricoverati di volta in volta, affetti da disturbo dello spettro di schizofrenico, disturbo bipolare, depressivo maggiore e di personalità. I livelli ematici dei lipidi sono stati confrontati tra soggetti ricoverati per un recente tentativo di suicidio e quelli senza tale storia recente. Inoltre, secondo l'ipotesi che collega impulsività e violenza con bassi livelli ematici di lipidi, è stata valutata l'associazione tra i livelli lipidici e il tentativo di suicidio con metodo violento. Risultati: Non abbiamo trovato alcuna associazione di colesterolo totale e LDL e trigliceridi con i tentativi di suicidio, analizzando anche per diagnosi e metodo di suicidio. Inoltre, un'analisi statistica post-hoc ha mostrato una tendenza verso la significatività (p = 0,06) nell'associazione tra un alto livello di colesterolo (≥160 mg / dL) e il recente tentativo di suicidio. Conclusioni: I nostri risultati non supportano l'ipotesi di associazione tra profili lipidici e tentativi di suicidio in soggetti con diversi disturbi mentali. Sono necessarie ulteriori ricerche per chiarire il ruolo dei marcatori biologici nei comportamenti suicidari.
Background: Subjects with mental disorders have a higher risk of suicide behaviors than the general population. So, to date, researchers have investigated some biomarkers possibly related to suicidality. Despite many studies have reported a possible relationship between low lipid serum levels and suicide attempt, conflicting results have emerged. Aim We investigated whether serum total cholesterol, LDL cholesterol and triglycerides are associated with recent suicide attempts in subjects with different mental disorders. Methods We conducted a cross-sectional study, including 593 consecutively admitted inpatients with schizophrenia spectrum, bipolar, major depressive, and personality disorders. Serum lipid levels were compared between subjects admitted for a recent suicide attempt and those without such recent history. Moreover, according to hypothesis that links impulsivity and violence with low serum lipid levels, the association between lipid levels and violent suicide attempt was assessed. Results We did not find any association of total and LDL cholesterol and triglycerides with suicide attempts, also considering diagnosis and suicide methods. In addition, a post-hoc analysis showed a trend toward significance (p=0.06) in the association between high cholesterol level (≥160mg/dL) and recent suicide attempt. Conclusions Our results do not support the hypothesis of association between lipid profiles and suicide attempts in subjects with different mental disorders. Further research is needed to clarify the role of biomarkers in suicidal behaviors.

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Trexler, Ryan Vincent. "Lipid Analysis and Microbial Community Characterization of Subsurface Shale". The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480679153855158.

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Cotte, Alexia. "Implication du métabolisme des phospholipides dans la progression et la résistance des cancers digestifs". Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCI019.

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Le métabolisme des lipides joue un rôle prépondérant dans le cancer. Ce métabolisme a pour effet, particulièrement grâce à la production de phospholipides (PLs), de supporter le niveau accru de prolifération mais aussi de réguler finement des mécanismes intra-cellulaires et extra-cellulaires qui promeuvent le maintien et la progression des cellules cancéreuses. Parmi tous ces acteurs, les gouttelettes lipidiques (GLs), connues pour leur fonction de réservoir, commencent à dévoiler leurs côtés sombres. Notre premier projet nous a permis de mettre en avant l’accumulation de GLs par des cellules de cancer colorectal (CCR) chimiorésistantes. La formation de GLs est régie par l’expression de l’enzyme lysophosphatidylcholine acyltransférase 2 (LPCAT2), permettant la production de phosphatidylcholine. Elle a pour effet de protéger le réticulum endoplasmique (RE) de l’induction d’un stress prévenant l’activation d’une mort cellulaire immunogène. Ces modulations lipidiques peuvent également se retrouver dans le plasma, où elles font l’objet de l’identification de biomarqueurs. Dans ce contexte, nous avons montré dans un second projet, que certains PLs pouvaient diagnostiquer la présence d’un carcinome hépatocellulaire (CHC) sur un foie cirrhotique. Ces deux aspects soulignent l’importance du métabolisme des PLs dans les cancers digestifs
Among all altered cancer metabolic pathways, lipid metabolism has a preponderant role in cancer development. This metabolism, especially through the production of phospholipids, supports high level of proliferation and carefully regulates intra-cellular and extra-cellular mechanisms promoting maintenance and progression of cancer cells. Among all metabolic players, lipid droplets (LD), known for their storage function, begin to reveal dark sides. Our first project led us to highlight LD involvement in the chemoresistance of colorectal cancer (CRC) cells. This resistance carries out thanks to LD accumulation during chemotherapy treatment. Their accumulation is regulated by the expression of lysophosphatidylcholine acyltransferase 2 (LPCAT2), leading to the production of phosphatidylcholine. It causes the protection of the endoplasmic reticulum (ER) stress induction preventing the activation of immunogenic cell death. These lipid modulations can also be found in plasma where they can be identified as biomarkers. In this context, we have shown that some phospholipids could prognosticate hepatocellular carcinoma (HCC) upon cirrhotic liver. These two aspects highlight the significance of phospholipid metabolism in digestive cancers

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Yoshinaga, Marcos Yukio. "\"Origem e composição da matéria orgânica e a dinâmica da comunidade microbiana em sedimentos superficiais de ecossistemas marinhos da costa sudeste do Brasil\"". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/21/21131/tde-09042007-163722/.

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A ciclagem de matéria orgânica (MO) no ambiente marinho é um processo-chave para o ciclo global de carbono. Os sedimentos costeiros são de suma importância para a ciclagem de carbono pois atuam como receptores de grandes quantidades de MO alóctone (i.e. terrestre) e autóctone (i.e. marinho). A miríade dos componentes orgânicos e suas diferentes características dificultam o entendimento das fontes de MO em ambientes costeiros. Este trabalho visou entender a origem e a composição da MO (através de biomarcadores lipídicos) e a dinâmica da comunidade microbiana (método ATP) em sedimentos superficiais de diferentes ecossistemas marinhos da costa sudeste do Brasil: (i) margem continental de Cabo Frio; (ii) sistema lagunar de Saquarema; (iii) áreas costeiras e a plataforma continental de Ubatuba; (iv) e a plataforma adjacente ao estuário de Santos. Os resultados apontaram uma origem predominantemente autóctone para a MO nestes sistemas, com contribuição terrestre reduzida e limitada à áreas próximas à costa. Processos oceanográficos e forçantes ambientais são cruciais para a composição da MO sedimentar e são discutidas para cada um dos ecossistemas estudados.
The cycling of the organic matter (OM) in the marine environment is a key process in the global carbon cycle. Coastal sediments are important to the global carbon cycle, since they receive large inputs from both marine and terrestrial OM. The myriad of organic compounds and their spectrum of reactivity complicate the understanding of OM sources in coastal environments. In this work, we aimed to access the origin and composition of the OM (through lipid biomarkers) and the microbial dynamics (ATP method) in surface sediments of diverse marine ecosystems from the SE Brazilian coast: (i) the continental margin off Cabo Frio; (ii) the lagoonal system of Saquarema; (iii) coastal and shelf areas from Ubatuba; and (iv) the continental shelf adjacent to Santos estuary. The results showed a dominance of autochthonous OM, with a minor fraction of the OM derived from terrestrial sources and restricted to areas close to the coast. Oceanographic processes and environmental forces are crucial to the composition of sedimentary OM and are discussed for each of those ecosystems.

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Persons, Jane Elizabeth. "Characterizing the relationship between low serum low-density lipoprotein and depressive symptoms". Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/5600.

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The purpose of this study was to resolve a critical gap in depression literature through assessment of the temporal relationship between depression and low LDL. A systematic review and meta-analysis was conducted to investigate the overall cross-sectional association between serum LDL and depression. Inconsistent findings suggest that more work must be done to clarify the link between LDL and depression. Next, Cox regression was used to explore the association between LDL and the subsequent onset of depressive symptoms within a subset of the Women’s Health Initiative cohort and evaluate the potential for effect modification by lipid-lowering medication use. This study provides evidence toward an association between low LDL and the subsequent onset of depressive symptoms, with increased risk confined to LDL below 100 mg/dL. Elevated risk was not associated with lipid-lowering medication use. The final study examined the differences in the magnitude and direction of change in serum LDL levels among individuals experiencing new-onset depression, and examines the potential for physical activity, energy intake, and total body weight to mediate the depression-LDL relationship. This study provides no evidence of an association between depression and subsequent serum LDL changes. Altogether, this data suggests that LDL that is below 100 mg/dL without the use of lipid-lowering medication may predispose individuals to a greater risk of depression, and also suggests that low LDL is not likely a state brought about by physiological or behavioral changes following the onset of depression.

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Jenkins, Benjamin John. "The role of alpha oxidation in lipid metabolism". Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/278025.

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Recent findings have shown an inverse association between the circulating levels of pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0) with the risk of pathological development in type 2 diabetes, cardio vascular disease and neurological disorders. From previously published research, it has been said that both these odd chain fatty acids are biomarkers of their dietary intake and are significantly correlated to dietary ruminant fat intake. However, there are profound studies that show the contrary where they do not display this biomarker correlation. Additionally, several astute studies have suggested or shown odd chain fatty acid endogenous biosynthesis, most often suggested via alpha oxidation; the cleavage of a single carbon unit from a fatty acid chain within the peroxisomes. To better understand the correlations and interactions between these two fatty acids with pathological development, the origin of these odd chain fatty acids needed to be determined, along with confirming their association with the disease aetiology. To minimise animal & human experimentation we made use of existing sample sets made available through institutional collaborations, which produced both animal and human interventional study samples suitable for odd chain fatty acid investigations. These sample collaborations allowed us to comprehensively investigate all plausible contributory sources of these odd chain fatty acids; including from the intestinal microbiota, from dietary contributions, and derived from novel endogenous biosynthesis. The investigations included two intestinal germ-free studies, two ruminant fat diet studies, two dietary fat studies and an ethanol intake study. Endogenous biosynthesis was assessed through: a stearic acid infusion, phytol supplementation, and an Hacl1 knockout mouse model. A human dietary intervention study was used to translate the results. Finally, a study comparing circulating baseline C15:0 and C17:0 levels with the development of glucose intolerance. We found that the circulating C15:0 and C17:0 levels were not significantly influenced by the presence or absence of intestinal microbiota. The circulating C15:0 levels were significantly and linearly increased when the C15:0 dietary composition increased; however, there was no significant correlation in the circulating C17:0 levels with intake. Circulating levels of C15:0 were affected by the dietary composition and factors affecting the dietary intake, e.g. total fat intake and ethanol, whereas circulating C17:0 levels were found to be independent of these variables. In our studies, the circulating C15:0 levels were not significantly affected by any expected variations in alpha oxidation caused by pathway substrate inhibition or gene knockout. However, C17:0 was significantly related, demonstrating it is substantially endogenously biosynthesised. Furthermore, we found that the circulating C15:0 levels, when independent of any dietary variations, did not correlate with the progression of glucose intolerance when induced, but the circulating C17:0 levels did significantly relate and linearly correlated with the development of glucose intolerance. To summarise, the circulating C15:0 and C17:0 levels were independently derived; the C15:0 levels substantially correlated with its dietary intake, whilst the C17:0 levels proved to be separately derived from its endogenous biosynthesis via alpha oxidation of stearic acid. C15:0 was found to be minimally endogenously biosynthesised via a single cycle of beta oxidation of C17:0 in the peroxisomes, however, this did not significantly contribute to the circulating levels of C15:0. Additionally, only the baseline levels of C17:0 significantly correlated with the development of glucose intolerance. These findings highlight the considerable differences between both of these odd chain fatty acids that were once thought to be homogeneous and similarly derived. On the contrary, they display profound dietary, metabolic, and pathological differences.

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