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1
Howell, Anne C. "Effects of antioxidant vitamin treatment on UV-irradiated cells." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/941360.
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Ultraviolet (UV) radiation damages both eukaryotic and prokaryotic cells by causing the formation of free radicals which damage cell membranes and DNA. Antioxidant vitamins have been shown to protect cells from UV-induced damage by scavenging free radicals. The protection of skin and its normal flora is necessary for the health of individuals in resisting diseases caused by microorganisms and delaying the long-term damage caused by UV radiation.This research investigated the effects of the antioxidants vitamin A and ascorbic acid, as well as UV-irradiation on both prokaryotic (Staphylococcus epidermidis) cells and eukaryotic (human fibroblast skin) cells. This information is important in determining the effects of vitamin treatment on skin and its normal flora.Results indicate that ascorbic acid is rapidly (within six hours) degraded after being dissolved in water or medium. Treatment of cells with ascorbic acid must take into account this rapid degradation. S.epidermidis cells were protected from UV-induced damage by treatment with ascorbic acid but were more sensitive to UV-irradiation when treated with vitamin A. Human fibroblast cells treated with ascorbic acid did not exhibit morphological changes when compared to untreated cells.Department of Biology
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Bryant, Rebecca Jane. "Effects of vitamins E and C on exercise-induced lipid peroxidation." Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1020147.
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The aim of this study was to examine whether vitamins E (200 IU) and C (1 g) in combination would influence exercise-induced lipid peroxidation to a greater extent than vitamin E (400 IU) alone. A placebo-controlled study was carried out on 7 collegiate cyclists who were supplemented with 1) vitamin C (1 g); 2) vitamins E (200 IU) and C (1 g); and vitamin E (400 IU) during 3 treatments, each 3 weeks in duration. The serum concentrations of hematocrit and MDA, one marker of lipid peroxidation, were measured immediately before, immediately after, and 24 hours after each exercise bout. After the vitamin C treatment, MDA serum concentration of the athletes (n=7) increased 85% above the baseline values of the placebo values, the vitamin E/C treatment showed a 29% increase, and the vitamin E treatment showed a 39% decrease. Pre- to post-exercise serum MDA levels increased 64% in the placebo group, a 29% increase in the vitamin C treatment group, a 23.2% increase in the vitamins E/C treatment group, and a 46.9% increase in the vitamin E treatment group. It is concluded that exercise-induced lipid peroxidation is more greatly influenced post-exercise by a combination of vitamins E (200 IU) and C (1 g), than by either vitamin C (1 g) alone, or vitamin E (400 IU) alone.Department of Family and Consumer Sciences
3
Winmill, Catherine Anne 1955. "EFFICACY OF CALCIUM AND VITAMIN D SUPPLEMENTATION IN REDUCING DIASTOLIC BLOOD PRESSURE IN A MILD HYPERTENSIVE MALE POPULATION." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276386.
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Abel, Stefan. "The physiological effect of vitamin B12 deficiency in human blood." Thesis, Stellenbosch : Stellenbosch University, 1990. http://hdl.handle.net/10019.1/69031.
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Thesis (MSc) -- Stellenbosch University, 1990.ENGLISH ABSTRACT: The main aim of this workpiece was to establish the physiological parameters against which a vitamin Bu deficiency could be measured. A comparison between the hematological values of healthy patients and those suffering from pernicious anemia due to vitamin Bu deficiency was done. A specific case of pernicious anemia was used in the comparison of abnormal values to the values of normal healthy patients. The comparison consisted of blood analyses with the help of specified instruments, photomicrographs of bone marrow and blood smears and statistical data. A Coulter Counter Model ZF was used for the hematological analyses of blood, a radio-isotope assay for serum vitamin B u was done and photomicrographs were taken with a NIKON Microflex camera with photomicrographic attachments. The importance of vitamin Bu has been shown in this workpiece. With the use of techniques and certain instruments, the effects of a shortage of vitamin Bu has been shown. Analyses of the blood from normal ,healthy patients was compared to that of patients suffering from pernicious anemia. It was demonstrated that pernicious anemia is characterized by a low erythrocyte count, hematocrit (Het), hemoglobin (Hb) and vitamin Bu levels together with a higher mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV). In severe cases of pernicious anemia these levels are extremely high or low as the case may be. Together with these values, the investigation of pernicious anemic blood and bone marrow smears revealed abnormally large erythrocyte precursors and fewer leucocytes than normal. Abnormally shaped cells, called macrocytes, were seen which was due to the disruption in deoxyribonucleic acid (DNA) synthesis caused by the vitamin Bu deficiency. This study produced a set of hematological reference values. The comparative study between healthy and pernicious anemic patients demonstrated a significant drop in serum vitamin B12 values during pernicious anemia. The hematological effect was illustrated by the Coulter Counter blood analysis results and the microscopic examination revealed the presence of megaloblastic erythrocytes, oval erythrocytes, pear-shaped poikilocytes and polymorphonuclear neutropbils with hypersegmented nuclei in blood smears I during vitamin B12 deficiency. This dianoses can be supported by the presence of megaloblasts and metamyelocytes in pernicious anemic bone marrow.
AFRIKAANSE OPSOMMING: Die hoof doel van hierdie werkstuk was om fisiologiese grense te bepaal waarteen 'n vitamien B12 tekort gemeet kan word. 'n Vergelyking tussen die hematologiese waardes van gesonde persone en die van pasiente met pernisieuse anemie wat ontstaan het as gevolg van 'n vitamien B12 tekort was uitgevoer. Die waardes verkry vanaf 'n spesifieke geval van pernisieuse anemie. was vergelyk met waardes vanaf normale gesonde persone. Hierdie vergelyking het bestaan uit bloed analises, fotomikrograwe van bloed en beenmurg smere en statistiese data. Die hematologiese bloed analises was met behulp van 'n Coulter Teller model ZF uitgevoer. 'n Radio-isotoop bepaling vir serum vitamien B12 was gedoen en fotomikrograwe was met 'n NIKON Microflex kamera geneem. Die belang van 'n vitamien B12 tekort was in hierdie werkstuk gedemonstreer. Die effek van hierdie tekort is deur die gebruik van sekere instrumente en tegnieke aangedui en die resultate hiervan is vergelyk tussen gesonde persone en pasiente met 'n vitamien B12 tekort. Hierdie studie het bevestig dat pernisieuse anemie gekenmerk word deur verlaagde eritrosiet, hematokrit (Het), hemoglobien (Hb) en vitamien B12 vlakke tesame met verhoogde gemene korpuskulere hemoglobien (GKH) en gemene korpuskulere volume (GKV) vlakke. Gedurende ernstige gevalle van pernisieuse anemie kan hierdie waardes uitermatig hoog of laag wees. Benewens hierdie waardes het die ondersoek van bloed en beenmurg gedurende vitamien B12 tekort, abnormale groot eritrosiet voorgangers en 'n verminderde hoeveelheid leukosiete getoon. Abnormale sel vorms was ook sigbaar a.g.v. die onderbreking in DNA sintese wat deur 'n vitamien B12 tekort veroorsaak word. Pernisieuse anemie word verkry wanneer daar 'n vitamien B12 en/of folaat tekort in die dieet is of wanneer hierdie vitamiene nie geabsorbeer kan word nie. Die teenwoordigheid van makrosiete, ovaal eritrosiete, peervormige poikilosiete en polimorfonuklere neutrofiele met hipergesegmenteerde keme in bloedsmere dui op 'n megaloblastiese anemie. Hierdie diagnose kan ondersteun word deur die aanwesigheid van megaloblaste en reuse metamielosiete in die beenmurg. Die bepaling van vitamien B12 en folaat vlakke in die bloed kan as addisionele bewysstukke vir 'n volledige diagnose dien. Gedurende hierdie studie is daar 'n stel hematologiese verwysingswaardes vasgestel. Die vergelykende studie tussen gesonde persone en pasiente met pernisieuse anemie het getoon dat daar 'n beduidende verlaging in serum vitamien B12 waardes gedurende pernisieuse anemie is. Die hematologiese effek was ook duidelik waameembaar in die Coulter teller se bloed analiese en mikroskopiese ondersoeke het die · teenwoordigheid van makrosiete, ovaal eritrosiete, peervormige poikilosiete en polimorfenuklere neutrofiele met hipersegmenteerde keme in bloedsmere aangedui. Hierdie diagnose kan ondersteun word deur die aanwesigheid van megaloblaste en reuse metamielosiete in die beenmurg.
This study was financially aided by a bursary from the CSIR.
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Farmer, Bertrand. "The status of beta carotene and vitamin A in Quebec dairy herds and their effects on reproductive performance /." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63167.
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Morton, Lincoln William. "The role of dietary phenolic compounds in the detoxification of reactive nitrogen species." University of Western Australia. Dept. of Medicine, 2003. http://theses.library.uwa.edu.au/adt-WU2003.0026.
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[Truncated abstract. Please see the pdf format for the complete text.] Interest in the role of peroxynitrite in the pathogenesis of atherosclerosis has increased due to many in vitro studies which have demonstrated its potent oxidising and nitrating capability and immunohistochemical staining studies which demonstrate nitration of tyrosine in vivo. It is frequently suggested that the production of nitric oxide and superoxide at sites of inflammation implicates peroxynitrite as the major damaging reactive nitrogen species in vivo. Evidence for a role for peroxynitrite is often demonstrated by measurement of 3-nitrotyrosine yet even this cannot distinguish peroxynitrite from other nitrating species. Clearly, however, if peroxynitrite is important in atherogenesis, then identification of mechanisms for its detoxification could provide a means of preventing such effects. Therefore, this Thesis has sought to determine whether phenolic compounds of dietary origin can be preferentially nitrated by reactive nitrogen species thereby protecting endogenous structures, such as low density lipoproteins, from atherogenic modifications. This Thesis focuses upon phenolic acids as they have received relatively less attention than other classes of phenolic compounds, such as flavonoids, yet they are quite abundant in socially important beverages such as red wine. In order to complete the required analyses, the development of methods to detect phenolic acids and their nitration products together with 3-nitrotyrosine, dityrosine and 5-nitro-γ-tocopherol was necessary. The initial in vitro experiments described herein sought to determine the products of reaction of peroxynitrite with phenolic acids of the 4-hydroxy and 3,4-dihydroxy type and then to examine whether these products could account for a protective effect upon tyrosine, lipids and endogenous anti-oxidants, if any was observed, when isolated LDL was treated with SIN-1, which releases peroxynitrite through the simultaneous generation of nitric oxide and superoxide. A concurrent minor focus was to examine the relationship between structure and activity of these phenolic acids under various regimes of oxidative insult. These experiments indicate that, at least in this in vitro model, oxidation is a dominant mechanism over nitration. Peroxynitrite was shown to nitrate coumaric acid in moderate yields but exclusive oxidation of caffeic acid appeared to occur. Although a potential role for γ-tocopherol as an anti-nitration agent was inferred, all types of chemical treatment of LDL in the presence of phenolic acids yielded oxidation as the primary end point. In fact, nitration of tyrosine was not detected and nitration of coumaric acid was at the limit of detection. Since nitration of tyrosine is generally regarded as important in many disease states, a more physiological nitrating mechanism involving artificially stimulated neutrophils was used. This system demonstrated that although physiologically relevant reactive nitrogen species can result in nitration of phenolic compounds, in a complex system including biological structures (LDL) and phenolic compounds, oxidation but not nitration of all species appears to occur. As a consequence of the results above, an examination of carotid plaque was undertaken to determine to what extent nitration occurred relative to oxidation in atherosclerotic tissue. These studies applied methods developed herein to detect 3-nitrotyrosine and dityrosine in complex biological matrices as markers of nitration and oxidation respectively. The data obtained demonstrated that nitration was a minor modification of protein (0.01%) compared to oxidation (0.3%) even in a highly diseased tissue such as carotid artery plaque. A secondary study examining plasma revealed that dityrosine, which has been implicated in irreversible albumin aggregation in chronic renal failure and more recently in heart disease, is elevated in chronic renal failure subjects compared to well matched controls. A separate examination of plasma from healthy subjects revealed that in both the fasting and post prandial state 3-nitrotyrosine could not be detected and, in fact, interfering species could be problematic in the GC-MS analysis of 3-nitrotyrosine. The lack of nitration of any substrate observed in vitro using reactive nitrogen species generated in the aqueous phase, the relative lack of nitration of tyrosine in plaque proteins and the lipophilicity of nitric oxide, the precursor of all reactive nitrogen species, suggested that nitration could be more closely associated with lipid structures. The known ability of γ-tocopherol to form 5-nitro-γ-tocopherol was used to probe this concept. The 5-nitro-γ-tocopherol content of lipid extracts obtained from carotid artery plaques was very high (30%). This indicated that nitration is predominantly a lipid phase phenomenon and that nitrating species are present in much greater abundance than oxidising species in vivo.
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Avery, Neva G. "The effects of vitamin E supplementation on the recovery from repeated bouts of resistance exercise." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1231405.
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The purpose of this study was to examine collegiate female swimmers' attitudes toward gender and coaching. The study also examined the coaching styles of male and females coaches and determined whether a difference between styles existed. A purposeful sample of 250 female swimmers from the Mid-American Conference (MAC) during the 2001-2002 swimming season participated in the study. Swimmers were required to have been coached by both female and male coaches in order to be eligible to participate. Addressing the purpose of this study, participants were asked to complete a 30-item questionnaire developed by the researcher. Frequency counts revealed that 23 of the 57 participants preferred a male coach to a female coach. Only two individuals reported their preference for a female with 32 participants citing no gender preference. Two sections, including 14 questions for each gender on the Gender Preference Instrument, assessed coaching style. Independent t -tests were calculated on each question (p < .05). Eight significant gender differences were observed on coaching styles, with the participating athletes scoring the male coach higher on all of the eight categories.School of Physical Education
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Poirier, Johanne 1959. "The effects of selenium and vitamin E intake on diet-induced oxidative stress and hyperlipidemia /." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31526.
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To examine the effects of fat composition and supplemental vitamin E (Vit E) and selenium (Se) on in vivo lipid peroxidation, diet-induced hypercholesterolemia, and glutathione (GSH) metabolism, male Syrian hamsters were fed for three weeks butter fat (BF-) or fish oil- (FO-)based diets supplemented with Vit E and/or Se. The effect of supplemental Vit E and Se on tissue lipid peroxidation (LPO), glutathione peroxidase (GSH-Px) activity and GSH concentrations differed between heart and liver and also was affected by dietary fat. The reduced glutathione/oxidized glutathione (GSH/GSSG) ratio was more consistently associated with tissue lipid peroxidation than was tissue Vit E content. Plasma lipids were lowered with supplemental Se and Vit E. Se supplementation, however, exerted a more potent hypolipidemic effect than Vit E. A pro-oxidative action of Se in hearts of FO-fed hamsters was noted, which was inhibited by supplemental Vit E. Hence, the combination of Vit E and Se may offer the most benefit against diet-induced oxidative stress and hyperlipidemia.
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Clarke, Michael William. "Vitamin E metabolism in humans." University of Western Australia. School of Medicine and Pharmacology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0191.
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[Truncated abstract] Vitamin E is comprised of a family of tocopherols (TOH) and tocotrienols. The most studied of these is [alpha]-tocopherol ([alpha]-TOH), as this form is retained within the body and any deficiency of vitamin E is corrected with this supplement. [alpha]-TOH is a lipid-soluble antioxidant required for the preservation of cell membranes and potentially acts as a defense against oxidative stress. Individuals who have a primary vitamin E deficiency such as low birth weight infants, secondary vitamin E deficiency due to fat malabsorption such as in abetalipoproteinaemia, or a genetic defect in TOH transport require supplementation. There is debate as to whether vitamin E supplementation in other patient groups is required. Vitamin E supplementation has been recommended for persons with FHBL, a rare disorder of lipoprotein metabolism that leads to low serum [alpha]-TOH and decreased LDL cholesterol and apolipoprotein B concentrations. We examined the effect of truncated apoB variants on vitamin E metabolism and oxidative stress in persons with heterozygous FHBL. We used HPLC with electrochemical detection to measure [alpha]- and [gamma]-TOH in serum, erythrocytes, and platelets, and GC-MS to measure urinary F2-isoprostanes and TOH metabolites as markers of oxidative stress and TOH intake, respectively. Erythrocyte [alpha]-TOH was decreased, but we observed no differences in lipid-adjusted serum TOHs, erythrocyte [gamma]-TOH, platelet [alpha]- or [gamma]-TOH, urinary F2-isoprostanes, or TOH metabolites. Taken together, our findings do not support the recommendation that persons with heterozygous FHBL should receive vitamin E supplementation. ... Sesame lignans are natural components of sesame seed oil and there is evidence that these lignans can inhibit CYP450 enzymes, in particular, those responsible for vitamin E metabolism. We hypothesised that sesame seed ingestion would increase serum [gamma]-TOH, lower plasma lipids and inhibit platelet function in human subjects with at least one cardiovascular risk factor. We used HPLC with electrochemical detection to measure [alpha]- and -TOH in serum and GC-MS to measure F2-isoprostanes and TOH metabolites as markers of oxidative stress and TOH intake, respectively. We used high-sensitive C-reactive protein as a measure of systemic inflammation. Platelet function was assessed using the PFA-100 platelet aggregation assay. Although serum [gamma]-TOH increased by 17%, we observed no effect on lipid metabolism, markers of inflammation, oxidative stress or platelet function following treatment with ~25 g/day sesame seeds for five weeks. Our findings challenge the hypothesis that sesame seed ingestion provides beneficial cardiovascular effects. In summary, we have studied the metabolism and transport of both [alpha]- and [gamma]-TOH in humans to evaluate the requirements for supplementation and the effects of vitamin E on platelet function and CYP3A4 activity. Specialised techniques using HPLC were developed to measure serum and cellular TOH concentrations both in supplemented and un-supplemented individuals. We also used GCMS to provide a sensitive, accurate assessment of TOH metabolites and midazolam pharmacokinetics in humans after vitamin E supplementation. We have examined the role vitamin E has on important biochemical endpoints, with emphasis on the implications for TOH supplementation in subjects at risk of CVD.
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Eiselstein, Emily M. "The effects of vitamin E supplementation and/or resistance exercise on insulin responsiveness in the elderly." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1239215.
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This purpose of this study was to determine the effects of vitamin E and/or resistance exercise on insulin resistance and glucose uptake. Nine subjects, who were currently active but not strength training, were assigned to either the vitamin E or placebo group based on their prescreening measurements. Subjects underwent a 3-week vitamin E washout period before testing. At baseline testing subjects were given a 75-gram glucose load and blood was drawn every 15-minutes for 2-hours to analyze insulin and glucose response. Another oral glucose tolerance test (OGTT) was performed 45minutes after a 50-minute full body progressive resistance training session to determine insulin and glucose response to exercise. Subjects ingested either the placebo (3 capsules of olive oil) or 1200 IU vitamin E (3 capsules) for 9-weeks. After 3-weeks of supplementation the subjects returned for another exercising OGTT. After this session the subjects began a 6-week progressive resistance exercise program, in which they performed another OGTT after the last session. Both groups showed a significant increase in strength gains pre and post resistance training. The statistical analysis failed to demonstrate any differences between groups in insulin or glucose response in any of the four OGTT trials, but there were multiple trends present. Combining vitamin E supplementation with resistance training increased insulin sensitivity and the disposal of glucose. Both groups also had significant strength gains from pre to post study. Future research is needed for verification of these trends.School of Physical Education
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Wanamaker, Scot E. "The effects of vitamin E supplementation and resistance training on muscle function in elderly subjects." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1231404.
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Findings were that caregivers considered all items on the Information Needs and Patient Care Needs subscales to be important but most of the unmet needs were from the Patient Care subscale. The needs less satisfied in relation to importance were (a) ways to improve patient appearance, (b) activities that will make patient feel purposeful, (c) information on how to give medications, (d) ways to reassure patient, (e) ways of coping with patient's diagnosis, (f) ways to dress patient comfortably, (g) ways to deal with patient's decreased energy, and (h) importance of not leaving patient alone.The implications for nursing are to assess and anticipate the needs of the caregiver of the stroke survivor so that his or her needs can be met. Preparing caregivers for their new role by meeting their needs will help the nurse met the primary goal of helping the patient.School of Physical Education
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Austin, Nicole. "Vitamin D, neuromuscular control and falling episodes in Australian postmenopausal women." University of Western Australia. School of Medicine and Pharmacology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0009.
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Falls in the older population have devastating consequences on the psychological and physiological health of the individual. Due to the complexity of interacting factors associated with ageing, pathology and falling episodes, determination of a primary cause or set of causes has been difficult to establish. Deficits in components of neuromuscular control have been widely studied with the coordinated interaction of sensory and motor system components being presented as a fundamental factor in the reduction of falling episodes. A causal relationship between deficits in vitamin D status and falling episodes has also been suggested. Furthermore, a relationship between poor vitamin D status, falling episodes and poor neuromuscular performance has been reported. The aims of the current study were designed to advance understanding in three aspects of the problem of falls prevention. Firstly an examination of the reliability of testing procedures commonly used in assessment of falls risk was undertaken. The Physiological Profile Assessment (PPA) testing procedure was selected as a commonly used tool and the reliability of its various components (sensory, motor and balance) was undertaken as an independent assessment of this approach to assessing falls propensity. Secondly, a case control study of fallers and non fallers was undertaken in which the neuromuscular tests evaluated in the reliability study were used to assess differences in neuromuscular control. The influence of vitamin D status on these measures was also considered. Thirdly, a 12-month randomised controlled trial of vitamin D/calcium supplementation or placebo/calcium was undertaken to identify the effect on falls outcome and individual measures of neuromuscular control.
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McMahon, Jennifer A., and n/a. "The effect of homocysteine lowering vitamins on cognitive performance in older people : a randomised controlled trial." University of Otago. Department of Human Nutrition, 2006. http://adt.otago.ac.nz./public/adt-NZDU20070426.154857.
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Background: Inverse associations have been reported between homocysteine concentrations and poor cognitive performance in several cross-sectional studies of healthy elderly subjects. Folate supplementation with or without vitamins B-12 and B-6 is an effective means of lowering homocysteine concentrations. Mood disturbances, from mild mood changes to clinical depression, are common in older populations. Several studies have shown that depressed people have lower levels of folate and vitamin B-12 and higher levels of homocysteine than non-depressed people. Improvement of mood has been reported in depressed people following supplementation with folic acid. Clinical trials are required to determine if lowering homocysteine concentration with vitamins improves cognitive function and/or mood in healthy elderly participants.
Objective: The primary aim of this research project was to carry-out a 2 year randomised, double-blind, placebo-controlled trial to determine if a supplement containing folate (1mg L-Mefolinic acid), vitamin B-12 (500(mu)g) and vitamin B-6 (10mg) improves scores or prevents decline on tests of cognition in a group of healthy older people ([greater than or equal to]̲ 65 years) with a plasma homocysteine concentration [greater than or equal to]̲13 (mu)mol/L. A second aim of this study was to determine if homocysteine lowering vitamins improved scores on tests of mood in this group.
Methods: Four hundred and sixty-five individuals, aged 65 and over, were recruited from Dunedin and surrounds, and asked to attend a screening clinic and provide a fasting blood sample. Two-hundred and seventy-six volunteers with a plasma homocysteine concentration [greater than or equal to]13(mu)mol/L were randomised to take either a combination of 1mg L-Mefolinic acid, 500(mu)g vitamin B-12 and 10mg vitamin B-6 or placebo for 2 years. A battery of cognitive tests and indices of mood was administered at baseline, one year, and two years. A fasting blood sample was collected at baseline and every six months thereafter.
Results: From baseline to 6 months of the intervention, homocysteine concentrations decreased by 37.5%, from 16.7 to 10.5 (mu)mol/L in the vitamin supplemented group and then plateaued. In the vitamin supplemented group there was a 181% increase in red blood cell folate concentration from a mean of 977 to 2752 nmol/L, and a 90.1% increase in plasma vitamin B-12 (from a mean 283 to 538 (mu)mol/L) over the study period of two years.
In the vitamin supplemented group there was a trend to poorer performance on almost all tests of cognition compared to placebo group. The vitamin group was 8% slower on Part B of the Reitan Trail Making Test, a test of speeded attention, mental tracking, visual search and mental flexibility (p=0.009). The vitamin group scored significantly lower on tests of short-term recall, Weschler Paragraphs (p=0.03) after 2 years, and the Rey Auditory Verbal Learning Test ((p=0.04) after one year, than the placebo group. There was no difference in mood score by treatment in this largely non-depressed group.
Conclusion: These results suggest a detrimental effect of high dose homocysteine lowering vitamin supplements on cognitive function in healthy older people. These results need to be confirmed in other randomised controlled trials.
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Murphy, Stephanie A. "Effects of selenium and vitamin B-6 on growth of chemically- induced transplanted tumors in BALB/c inbred mice." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43906.
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Male weanling inbred, mice were inoculated with
fibrosarcoma cells (hindquarter) originally produced by 2-methylcholanthrene. Before inoculation, mice were randomly divided into three groups of 24 and one of 12
(control). After a one week acclimation period, each group was fed a diet containing either suboptimal vitamin B-6, 0.5 mg/kg diet; adequate, 7.0 mg/kg diet; or excess, 100 mg/kg diet. Controls were fed the adequate vitamin. B-6 diet. Twenty-four hours after
tumor cell inoculation, a series of sodium selenite injections (0.5 μg/.10 mL) were given to half of each treatment group and all controls. Mice were sacrificed
two wk after tumor inoculation. Tumors were excised and weighed. Selenium-treated mice had significantly smaller tumors as compared to untreated mice regardless
of vitamin B-6 treatment. The smallest tumors were
found in the selenium-treated group maintained on
adequate B-6, while the largest tumors were developed
by mice on the excess B-6 diet without selenium treatments.
All groups had similar blood selenium levels as
measured by gas chromatography. Tumor selenium levels,
analyzed by atomic absorption, were significantly
higher for untreated groups than selenium-treated
groups (larger tumor size). The excess and adequate
vitamin B-6 selenium-treated groups had significantly
lower tumor selenium levels than the adequate vitamin
B-6 untreated group. Plasma pyridoxal phosphate
(concentrations) determined radiometrically and tumor
vitamin B-6 levels determined microbiologically, related directly to dietary treatments. Sodium selenite
injections and adequate vitamin B-6 diets reduced the
size of fibrosarcomas in BALB/c inbred mice.Master of Science
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Mason, Shelley S. "Exploring Tissue Engineering: Vitamin D3 Influences on the Proliferation and Differentiation of an Engineered Osteoblast Precursor Cell Line During Early Bone Tissue Development." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1000.
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Most of the load-bearing demand placed on the human body is transduced by skeletal tissue, and the capacity of the skeleton to articulate in various opposing directions is essential for body movement and locomotion. Consequently, cartilage and bone defects due to trauma, disease, and developmental abnormalities result in disabling pain and immobility for millions of people worldwide. A novel way of promoting cartilage and bone regeneration is through the incorporation of either primary cells or multipotent progenitor cells in a three-dimensional (3D) biomaterial scaffold, and/or the addition of exogenous growth and differentiation factors. The first part of this study reports a protocol for using freshly isolated mature chondrocytes seeded in a 3D hydrogel biomaterial scaffold, developed to explore mechanotransduction of engineered cartilage constructs cultured in a designed bioreactor. The bioreactor was designed to allow the application of physiological mechanical forces (compression and fluid flow), as well as a non-invasive/non-destructive method for analyzing regenerating tissue in real time through ultrasound transducers and a computerized monitoring system. In the second part of this study, an engineered immortalized osteoprecursor cell line, designated OPC1 (osteoblastic precursor cell line 1), was used as a culture model system for exploring the effects of exogenous growth and differentiation factors, mainly vitamin D, on early bone development. OPC1 was previously designed to provide a consistent reproducible culture system for direct comparisons of engineered bone constructs, evaluating bone development and cell/biomaterial interactions, and for investigating putative bone differentiating factors. One of the objectives of this research effort was to explore tissue development and regeneration by culturing OPC1 in the presence of vitamin D metabolites vitaD3 and 1,25OH2D3, while assaying the concomitant biological response. Results indicate that OPC1 is capable of metabolizing the parental metabolite vitaD3, and thus 25OHD3, to the active vitamin D form 1,25OH2D3. The metabolism of vita3 resulted in an anti-proliferative and pro-differentiative influence on OPC-1. These results support the hypothesis that extra-endocrine synthesis of 1,25OH2D3 functions in a tissue specific manner to regulate growth and differentiation, in addition to the classic calcimic actions of the vitamin D endocrine pathway. Understanding the influence of vitamin D on bone development will have significant implications on healthy aging, including the susceptibility to skeletal disorders involved in development and aging, such as osteoarthritis (OA) and osteoporosis.
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Cobb, Jennifer L. "Validation of a Sun-Exposure Questionnaire for Adolescent Girls." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/CobbJL2001.pdf.
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Liu, Chia-chi. "Oxidation of ascorbate by protein radicals in simple systems and in cells." Phd thesis, Australia : Macquarie University, 2007. http://hdl.handle.net/1959.14/16746.
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Thesis (PhD) -- Macquarie University, Division of Environmental and Life Sciences, Dept. of Chemistry and Biomolecular Sciences, 2007.Bibliography: leaves 295-322.
Generation of peroxide groups in proteins exposed to a wide variety of reactive oxygen species (ROS) requires an initial formation of protein carbon-centred or peroxyl free radicals, which can be reduced to hydroperoxides. Both protein radicals and protein hydroperoxides are capable of oxidizing important biomolecules and thus initiate biological damage. In this study, we investigated the inhibition of protein hydroperoxide formation by ascorbate and GSH in gamma-irradiated HL-60 cells.--We used HL-60 cells as a model for general protection of living organisms by ascorbate (Asc) and glutathione (GSH) from the deleterious effects of protein hydroperoxides generated by radicals produced by gamma radiation. Measurement by HPLC indicated that incubation of HL-60 cells with Asc in the presence of ascorbate oxidase resulted in the accumulation of intracellular Asc. The intracellular Asc levels were lowered by irradiation, demonstrating intracellular consumption of Asc by the radiation-generated radicals. Exposure of HL-60 cells to increasing gamma irradiation doses resulted in increasing accumulation of protein peroxides in the cells. This was measured by the FOX assay. A significant decrease in intracellular protein hydroperoxides was noted when the cells were treated with ascorbic acid before irradiation. A dose-dependent protective effect of Asc was observed. Asc loading also provided strong protection from radiation-generated protein hydroperoxides independently of the composition of the external medium, showing that only the radicals formed within the cells were effective in oxidizing the cell proteins. Similarly, protein peroxidation was inhibited in cells with enhanced levels of GSH and increased when the intracellular GSH concentration was reduced. These findings indicate that ascorbate and GSH are important antioxidants in protecting cells from oxidative stress associated with the generation of protein hydroperoxide.
Mode of access: World Wide Web.
xxix, 322 leaves ill
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Johnson, Lyn. "Regulation of hepatic catabolism in the physiological economy of vitamin D." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254250.
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Udagawa, Miho. "Studies on Distribution and Physiological Function of Vitamin K in Fish." Kyoto University, 2001. http://hdl.handle.net/2433/150325.
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Zeferino, Cynthia Pieri [UNESP]. "Resposta fisiológica, qualidade da carne e expressão gênica no músculo esquelético de frangos de corte sob estresse por calor que receberam antioxidantes na dieta." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/104104.
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Universidade Estadual Paulista (UNESP)
A temperatura ambiente elevada representa o principal fator limitante do desenvolvimento da produção avícola em regiões de clima quente. O objetivo do trabalho foi verificar se a dieta suplementada com vitaminas C e E, seria capaz de neutralizar, ou reduzir, os efeitos do estresse por calor, aplicado dos 28 aos 42 dias de idade, sobre a resposta fisiológica, o desempenho, rendimento de carcaça e qualidade da carne de frangos. Foram utilizados 384 frangos de corte machos distribuídos num delineamento inteiramente casualizado, com arranjo fatorial 2 x 3 (com e sem suplementação da dieta com vitaminas e temperaturas ambientais associadas ao pair-feeding) e 16 repetições. As aves foram mantidas em termoneutralidade até os 28 dias. A partir desta idade, foram alojadas em grupos de quatro por gaiola, em três salas climatizadas: duas termoneutras (22,6 e 22,5ºC) e uma de estresse por calor (31,7ºC). Metade das aves recebeu dieta suplementada com vitaminas C (536 mg/kg) e E (127 mg/kg). Na sala de estresse por calor as aves tiveram livre acesso à ração; nas salas termoneutras metade das aves recebeu ração à vontade e a outra metade recebeu quantidade limitada, no sistema pair-feeding. Foram avaliados a temperatura retal e da superfície da pele e características de desempenho, rendimento de carcaça e qualidade instrumental da carne. As análises de qualidade de carne foram realizadas no músculo pectoralis major (peito) 24 horas após o abate. A suplementação da dieta com vitaminas C e E não foi capaz de neutralizar, nem de reduzir, os efeitos negativos do estresse por calor sobre as características de desempenho, rendimento de carcaça e qualidade de carne das aves. A semelhança nos resultados de desempenho entre aves em estresse por calor e em pair-feeding sugere que a queda no desempenho sob estresse por calor deveu-se, principalmente, à redução no consumo de alimentos
Elevated ambient temperature represents the main limiting factor for the development of chicken production in hot climate regions. The objective of this study was to evaluate if the diet supplemented with vitamins C and E would be able to reduce, or neutralize the negative effects of heat stress applied between 28 and 42 days of age, on the physiological response, performance, slaughter yield and meat quality of chickens. A total of 384 male broiler chickens were assigned to a completely randomized design, with a 2 x 3 factorial arrangement (diet with or without vitamins supplementation and ambient temperatures associated with pair-feeding) and 16 replications. The chickens were kept in thermoneutral conditions up to 28 days of age. From this age and on, were housed in groups of four per cage, in three environmentally controlled chambers: two were thermoneutral (22,6 e 22,5ºC) and one for heat stress (31,7ºC). Half the chickens were offered a diet supplemented with vitamins C (536 mg/kg) and E (127 mg/kg). In the heat stress chamber, the chickens had free access to the feed; in the thermoneutral chambers half the chickens had free access to the feed and the other half received a limited amount, in a pair-feeding system. Rectal and body surface temperatures and performance, slaughter yield and meat quality traits were evaluated. Meat quality analyses were performed in the pectoralis major muscle 24 hours after slaughter. Diet supplementation with vitamins C and E were not able to neutralize, neither to reduce, the negative effects of heat stress on the performance, slaughter yield and meat quality traits. The similarity of performance results between the chickens submitted to heat stress and pair-feeding, suggested that the reduction in performance under heat stress were due mainly to the drop in feed consumption
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Zeferino, Cynthia Pieri 1981. "Resposta fisiológica, qualidade da carne e expressão gênica no músculo esquelético de frangos de corte sob estresse por calor que receberam antioxidantes na dieta /." Botucatu : [s.n.], 2012. http://hdl.handle.net/11449/104104.
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Orientador: Ana Silvia Alves Meira Tavares MouraBanca: José Roberto Sartori
Banca: Dirlei Antonio Berto
Banca: Luiz Lehmann Coutinho
Banca: José F. M. Mendes
Resumo: A temperatura ambiente elevada representa o principal fator limitante do desenvolvimento da produção avícola em regiões de clima quente. O objetivo do trabalho foi verificar se a dieta suplementada com vitaminas C e E, seria capaz de neutralizar, ou reduzir, os efeitos do estresse por calor, aplicado dos 28 aos 42 dias de idade, sobre a resposta fisiológica, o desempenho, rendimento de carcaça e qualidade da carne de frangos. Foram utilizados 384 frangos de corte machos distribuídos num delineamento inteiramente casualizado, com arranjo fatorial 2 x 3 (com e sem suplementação da dieta com vitaminas e temperaturas ambientais associadas ao pair-feeding) e 16 repetições. As aves foram mantidas em termoneutralidade até os 28 dias. A partir desta idade, foram alojadas em grupos de quatro por gaiola, em três salas climatizadas: duas termoneutras (22,6 e 22,5ºC) e uma de estresse por calor (31,7ºC). Metade das aves recebeu dieta suplementada com vitaminas C (536 mg/kg) e E (127 mg/kg). Na sala de estresse por calor as aves tiveram livre acesso à ração; nas salas termoneutras metade das aves recebeu ração à vontade e a outra metade recebeu quantidade limitada, no sistema pair-feeding. Foram avaliados a temperatura retal e da superfície da pele e características de desempenho, rendimento de carcaça e qualidade instrumental da carne. As análises de qualidade de carne foram realizadas no músculo pectoralis major (peito) 24 horas após o abate. A suplementação da dieta com vitaminas C e E não foi capaz de neutralizar, nem de reduzir, os efeitos negativos do estresse por calor sobre as características de desempenho, rendimento de carcaça e qualidade de carne das aves. A semelhança nos resultados de desempenho entre aves em estresse por calor e em pair-feeding sugere que a queda no desempenho sob estresse por calor deveu-se, principalmente, à redução no consumo de alimentos
Abstract : Elevated ambient temperature represents the main limiting factor for the development of chicken production in hot climate regions. The objective of this study was to evaluate if the diet supplemented with vitamins C and E would be able to reduce, or neutralize the negative effects of heat stress applied between 28 and 42 days of age, on the physiological response, performance, slaughter yield and meat quality of chickens. A total of 384 male broiler chickens were assigned to a completely randomized design, with a 2 x 3 factorial arrangement (diet with or without vitamins supplementation and ambient temperatures associated with pair-feeding) and 16 replications. The chickens were kept in thermoneutral conditions up to 28 days of age. From this age and on, were housed in groups of four per cage, in three environmentally controlled chambers: two were thermoneutral (22,6 e 22,5ºC) and one for heat stress (31,7ºC). Half the chickens were offered a diet supplemented with vitamins C (536 mg/kg) and E (127 mg/kg). In the heat stress chamber, the chickens had free access to the feed; in the thermoneutral chambers half the chickens had free access to the feed and the other half received a limited amount, in a pair-feeding system. Rectal and body surface temperatures and performance, slaughter yield and meat quality traits were evaluated. Meat quality analyses were performed in the pectoralis major muscle 24 hours after slaughter. Diet supplementation with vitamins C and E were not able to neutralize, neither to reduce, the negative effects of heat stress on the performance, slaughter yield and meat quality traits. The similarity of performance results between the chickens submitted to heat stress and pair-feeding, suggested that the reduction in performance under heat stress were due mainly to the drop in feed consumption
Doutor
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Haaften, Rachel I. M. van. "Effect of vitamin E on glutathione-dependent enzymes." [Maastricht] : Maastricht : UMP, Universitaire Pers Maastricht ; University Library, Maastricht University [Host], 2003. http://arno.unimaas.nl/show.cgi?fid=6339.
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Hogan, Kyla B. "The hemostatic responses to exercise in hot and cold temperatures." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1398717.
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Purpose: The impact of temperature on the coagulative response to exercise has not been well described. The purpose of this study was to assess the response of plasma thrombin-antithrombin (TAT) to exercise during exposure to both hot and cold temperatures, and to compare those responses to exercise under normal, temperate conditions. Methods: Fifteen healthy male subjects (25.3 + 4.3 years) volunteered to participate in this study. Subjects completed maximal cycle ergometer exercise tests in three different temperatures (20°C, 5° or 8° C, and 30°C) in an environmental chamber. All tests were conducted in random order and separated by at least seven days. Blood samples were obtained before and immediately after exercise and analyzed by Elisa to determine plasma concentrations of thrombin-antithrombin complex (TAT). Results: Subjects demonstrated significantly elevated plasma levels of TAT in all three temperatures immediately after exercise (normal =1.04 ± 0.44 ng/ml, cold =1.34 ± 0.79 ng/ml, hot =1.18 + 0.95 ng/ml) when compared to baseline measures (normal = 0.45 ± 0.26 ng/ml, cold = 0.88 + 0.57 ng/ml, hot = 0.64 + g/ml). Subjects also showed significant elevations in TAT concentrations both before and after exercise in the cold temperature when compared with the normal temperature. There was no significant difference between the hot and normal temperatures. Conclusion: An individual's coagulation potential is increased following maximal physical exertion and may be further increased by exposure to colder temperature. Key Words: coagulation, physical exertion, temperature, thrombosis.School of Physical Education, Sport, and Exercise Science
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Xu, Fan 1960. "Effect of prolonged exercise on running economy." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68149.
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The purpose of this study was to investigate the effect of prolonged exercise on running economy. Fourteen male long distance runners performed two 90 minute runs on an outdoor 400m track at velocities equal to 65 and 80% of VO$ sb2$max. Prior to and following each 90 minute run, running economy (RE) was measured as the steady-state VO$ sb2$ during treadmill runs at speeds of 188 and 228 m/min. During the 90-min run at 65% of VO$ sb2$max, the mean weight loss was 1.3 kg. The HR was 143 bpm between minutes 5-10 and increased to 150 bpm between minutes 85-90. During the 90-min run at 80% of VO$ sb2$max, the mean weight loss was 1.4 kg. The HR was 161 bpm between minutes 5-10 and increased to 165 bpm between minutes 85-90. When the post RE test was conducted following each 90-min run, there was a significant increase in VO$ sb2$ expressed in both l/min and ml/kg$ cdot$min (a decrease in running economy). The increase in oxygen cost of running following the 90-min run at 80% of VO$ sb2$max was greater than that following the run at 65% of VO$ sb2$max.
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Albenali, Lujain. "The effect of vitamin D supplementation on atopic dermatitis." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4510/.
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Atopic Dermatitis(AD)is recognized as one of the major worldwide health concerns. Despite being first described in the nineteenth century by Besnier, management options continue to be limited and are primarily palliative. AD patients are susceptible to many infections, such as the Herpes simplex virus (HSV), resulting in a more serious clinical subgroup of patients with AD complicated by Eczema Herpeticum (ADEH). Supplementation with vitamiD (VD)has shown positive effects on the clinical outcome of AD in previous randomized controlled trials and clinical studies which could be due, in part, to the up regulation the antimicrobial peptide LL‐37, which has known antimicrobial, immune-modulatory and wound healing effects. Objective: We sought to determine the level of VD deficiency in AD and ADEH patients in a pediatric dermatology clinic,to investigate whether there was a difference in baseline VD levels between AD and ADEH, to examine skin surface LL-37 levels in both and to establish whether VD supplementation would result in clinical improvement. Methods: A practice evaluation study was performed at the Sheffield Children’s Hospital. All AD patients were screened for VD deficiency. Those that were found deficient were assessed using SCORAD and POEM. Skin surface cells were collected from lesional and non-lesional sites using a novel non-invasive technique for LL-37 evaluation. In addition, serum IgE levels and serum calcium levels were also checked. Supplementation was then commenced for two months after which clinical severity was reassessed and all levels were rechecked. Results: Ninety children (mean age9) were screened for VD deficiency; 83% had low VD levels. VD levels were significantly lower in ADEH children than AD children (p <0.0001). Baseline SCORAD was also significantly higher in ADEH patients (p < 0.0001). Skin surface LL-37 levels were reduced in ADEH patients in comparison to AD patients (p = 0.46), and were significantly reduced in patients with severe AD (SCORAD>50) in comparison to patients with moderate (SCORAD 25-‐50) or mild AD (SCORAD <25; p=0.018). Two months of VD supplementation resulted in significant improvement of SCORAD (p <0.0001) and POEM (p < 0.0001) in both groups; LL-37 levels also increased significantly (p = 0.0004). Conclusions: VD deficiency was found to be common in AD children, and VD supplementation reduced ADEH and AD severity in children. Part of the explanation is through increased LL-37 production.
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Pietrzak, Ewa M. "Vitamin E as an index of tissue peroxidation: The effect of vitamin C deficiency and ischemia/reperfusion." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6464.
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Levels and turnover of vitamin E ($\alpha$-T) were studied in guinea pigs placed for three weeks on a diet containing a scorbutic level of vitamin C and either a low level (LE group) or a high level (HE group) of hexadeuterium-labelled vitamin E (d$\sb6$-RRR-$\alpha$-T acetate). The levels of vitamin C in the ten tissues analyzed declined very rapidly at rates that were the same in both the LE and HE groups, indicating that the level of dietary vitamin E had no effect upon tissue vitamin C levels. On the vitamin C deficient diet, the total $\alpha$-T (d$\sb0$- + d$\sb6$-$\alpha$-T) declined significantly over 21 days in the HE group in two tissues with high P-450 enzyme activity and in one tissue with a high partial pressure of oxygen, whereas on a vitamin C-sufficient diet with the same concentration of vitamin E the levels of total $\alpha$-T remained steady in the same tissues. In the LE "scorbutic" group, the total $\alpha$-T declined only in heart and kidney, whereas in the vitamin C-sufficient LE group there was a decline of total $\alpha$-T in all tissues analyzed except brain. The results show that in guinea pigs, at least, vitamin C is indispensable for proper uptake of vitamin E from the gut and absorption into tissues. Changes of vitamin E levels also were studied in six anatomical regions of the brain of rats subjected to controlled ischemia/reperfusion. Analysis showed that ischemia/reperfusion caused statistically significant losses of vitamin E in all regions, except the pons-medulla, and the extent of loss correlated well with the previously determined deterioration of the blood-brain barrier in the corresponding regions. (Abstract shortened by UMI.)
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Gallo, Sina. "An examination of parental compliance with vitamin D recommendations and the physiological responses to vitamin D isoform and dosage in breastfed infants from greater Montréal." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116878.
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Vitamin D is important to maintain calcium homeostasis and promote healthy bone development. Breastfed newborns are at heightened risk of vitamin D deficiency because breast milk contains insufficient amounts of vitamin D. Canadian health policy recommends all breastfed infants receive 400 IU/d of vitamin D starting at birth and continuing until infants can obtain this amount through diet. Both dietary and endogenous production of vitamin D are commonly measured using the 25-hydroxyvitamin D metabolite (25(OH)D), as it has a longer half-life and is less hormonally regulated than the active form, 1,25-dihydroxyvitamin D. The Institute of Medicine (IOM) defines the amount necessary to meet the needs of 97.5% of a population group as the Recommended Dietary Allowance (RDA), however due to insufficient supportive data for the 0-12 mo age group an Adequate Intake (AI) level of 400 IU/d was established instead. This amount is thought to maintain circulating 25(OH)D concentrations in the range of 40-50 nmol/L, sufficient for bone health. Others argue concentrations >75 nmol/L are necessary and that some infants and children may require 800 IU/d of vitamin D supplementation. Despite these recommendations, many infants in Canada have low circulating 25(OH)D concentrations. It is unclear whether these low concentrations are due to a lack of compliance or that the recommendations are insufficient to achieve the desired circulating 25(OH)D concentrations. In addition, whether intakes of vitamin D >400 IU/d in infancy are associated with better bone mineral accrual has not been systematically tested. There are two isoforms of vitamin D which are available as supplements in Canada, cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2). Controversy exists regarding the biological effectiveness of both forms to increase 25(OH)D concentrations. Health Canada's 2004 recommendation states vitamin D2 is less effective than D3 for supplementation, yet no studies have directly compared the efficacy these isoforms in infants. The global objectives of this thesis are to: (1) describe vitamin D supplementation practices of mothers of newborns from a large Canadian urban center; (2) compare the biological response to supplemental vitamin D2 and D3 isoforms in breastfed infants from 1 to 4 mo of life; and (3) define the dosage requirement of vitamin D3 based on (a) the amount necessary to raise plasma 25(OH)D to ≥75 nmol/L in 97.5% of infants (as used in setting the RDA) and (b) using measures of mineral homeostasis, growth and bone mass. Study 1 consisted of a telephone survey with 342 mothers who delivered at the Royal Victoria Hospital (Montréal, Québec), representing ~10% of all annual births at this center. Mothers were contacted 6-12 mo post-partum and asked about vitamin D supplementation practices including the amount and frequency of dosage as well as reasons for non-adherence. Study 2 was a randomized clinical trial (RCT) of 52 breastfed infants. At 1 mo of age, infants received 400 IU/d of either vitamin D2 or D3 for 3 mo. The change in plasma 25(OH)D concentrations as well as the proportion of infants which achieved ≥50 and ≥75 nmol/L plasma 25(OH)D targets were compared between groups. Study 3 was a RCT in which 132 healthy, breastfed 1 mo old infants were randomly assigned to receive one of 4 vitamin D dosages (400, 800, 1200 or 1600 IU/d of vitamin D3).La vitamine D est importante pour maintenir l'homéostasie du calcium et pour promouvoir le développement des os. Les nouveau-nés allaités ont un risque accru en carence de vitamine D car le lait maternel est insuffisant en vitamine D. Santé Canada recommande que tous les nourrissons allaités reçoivent 400 UI/jour de vitamine D dès la naissance et jusqu'à ce qu'ils puissent obtenir cette quantité par l'alimentation. La production alimentaire et endogène de la vitamine D est généralement mesurée en utilisant le métabolite 25-hydroxyvitamine D (25(OH)D) car il a une demi-vie plus longue et est moins contrôlé par les hormones que la forme active, soit la 1,25-dihydroxyvitamine D. L'Institute of Médicine (IOM) définit la quantité nécessaire pour répondre aux besoins de 97,5% d'une population avec l'apport nutritionnel recommandé (ANR), mais en raison de l'insuffisance des données scientifiques pour le groupe d'âge 0 à 12 mois, un apport suffisant de 400 UI/jour a été créé à la place. Cette quantité est jugée suffisante pour maintenir les concentrations plasmatique de 25(OH)D dans la gamme de 40-50 nmol/L, suffisante pour la santé des os. D'autres soutiennent que des concentrations >75 nmol/L sont nécessaires et peuvent nécessiter 800 UI/ jour de vitamine D pour certains nourrissons et enfants. Malgré ces recommandations, certains nourrissons au Canada ont des concentrations faibles de 25(OH)D. Il est difficile de savoir si ces faibles concentrations sont dues à un non suivi de la posologie ou parce que les recommandations sont insuffisant pout atteindre des niveau sanguins de 25(OH)D désirée. À ce jour, les résultats quant a savoir si les apports en vitamine D de >400 UI/jour pendant l'enfance ont des conséquences bénéfiques sur l'accumulation du contenu minéral osseux n'ont pas étés explorés scientifiquement. Il existe deux isoformes de la vitamine D qui sont disponibles sous forme de suppléments au Canada, soit cholécalciférol (vitamine D3) et ergocalciférol (vitamine D2). Il y a une controverse quant à l'efficacité biologique de ces deux formes ayant pour effet d'augmenter les niveaux sanguins de 25(OH)D. Santé Canada à stipulé dans sa recommandation de 2004, que la vitamine D2 est moins efficace que la D3 hors, aucune étude n'a comparé l'efficacité de ces isoformes directement chez les nourrissons. L'objectif global de cette thèse est de: (1) décrire les pratiques de suppléments de la vitamine D par la mère du nouveau-né, dans un grand centre urbain au Canada, (2) de comparer la réponse biologique à un supplément de vitamine D2 vs. D3 chez les nourrissons allaités de 1 à 4 mois de la vie, et (3) définir le dosage quotidien de la vitamine D3 en fonction de la quantité nécessaire pour (a) élever les niveaux plasmatique de 25(OH)D ≥75 nmol /L dans 97,5% des nourrissons (telle qu'était utilisée dans la détermination de l'ANR) et (b) utilisant des mesures de l'homéostasie minérale, de la croissance et du contenu de la masse osseuse. L'étude 1 a consisté d'une enquête téléphonique auprès de 342 mères ayant accouchées à l'hôpital Royal Victoria (Montréal, Québec), représentant environ 10% de toutes les naissances annuelles à Royal Victoria. Les mères ont étés contactées entre 6 à 12 mois post-partum, et questionnées sur les pratiques quant aux suppléments en vitamine D, en particulier sur la quantité et la fréquence des doses ainsi que les raisons du non-respect. L'étude 2 était un essai clinique aléatoire (ECR) de 52 nourrissons allaités d'un mois d'âge. Ces nourrissons ont reçu 400 UI/jour de vitamine D2 ou D3 pour une durée de 3 mois. Le changement dans les niveau plasmatique de 25(OH)D ainsi que la proportion de nourrissons qui ont atteint ≥50 et ≥75 nmol/L de 25(OH)D ont été comparés entre les deux groupes. L'étude 3 était un ECR dont 132 bébés allaités d'un mois d'âge, en bonne santé, ont étés assignés au hasard à recevoir l'une des 4 doses de vitamine D3 (400, 800, 1200 ou 1600 UI/jour).
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Anderson, Dawn E. "Effects of caffeine on the metabolic and catecholamine responses to exercise in 5 and 28p0sC environments." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/833465.
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The influence of caffeine on the metabolic and catecholamine responses to mild exercise in a cold and a warm environment was studied in eight healthy males. The subjects performed 60 minutes of cycling at 50% VO2max in a cold environment (5°C and 70% relative humidity) and a warm environment (28°C and 50% relative humidity) 30 minutes after ingesting caffeine (5mg/kg body weight) or placebo (dextrose). Caffeine ingestion prior to exercise in the warm environment resulted in increased plasma epinephrine, with no effect on plasma norepinephrine. Neither lipid nor carbohydrate metabolism was altered by caffeine in the warm trial. Exercise in the cold environment (placebo) produced increased oxygen consumption and carbohydrate metabolism, decreased lipid metabolism, and no difference in plasma catecholamines compared with the warm-placebo trial. Responses to the combination of caffeine ingestion and the cold environment did not differ from cold-placebo responses in oxygen consumption or respiratory exchange ratio during the cycling bout. However, in the cold-caffeine trial plasma epinephrine was elevated. In addition, fat oxidation, serum free fatty acids, and serum glycerol were elevated in the cold-caffeine condition. Carbohydrate oxidation was depressed, while serum glucose and blood lactate were elevated in this trial. The results of this study indicate that caffeine increases plasma epinephrine; cold increases oxygen consumption and carbohydrate metabolism, while decreasing lipid metabolism; and the combination of caffeine and cold during exercise increases plasma epinephrine and lipid metabolism, but decreases carbohydrate metabolism.Human Performance Laboratory
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Martin, David E. "The effect of heat stress on excess post exercise oxygen consumption." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/834623.
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While a great deal of research has been directed towards the phenomena of excess post exercise oxygen consumption (EPOC), the effect of thermal stress on EPOC is not well defined. To assess the effect of heat stress on EPOC, seven healthy, active subjects (4 female, 3 male; 23.9 ± 2.0 years of age) performed 4 trials: one control (quiet rest) and one exercise (45 minutes of cycling at 65% VO2max workload) trial in moderate (23° C, 50% humidity) and hot (35° C, 50% humidity) environments. Oxygen consumption (V02), heart rate (HR) and rectal temperature (RT) were assessed pre, during and post control or exercise. Subjects were monitored until post exercise VO2 had returned to within ±2% of baseline. EPOC was determined by subtracting baseline VO2 from total V02 during the post exercise period. During the first 15 minutes (acute) post exercise, a significant EPOC (p = 0.0019) was seen in both exercise conditions over both control conditions. During the slow phase (> 15 minutes post exercise to baseline), there was no significant difference between the hot control (HC), moderate exercise (ME), or hot exercise (HE) EPOC. Total time post exercise until baseline was achieved was 35, 44, and 51 minutes for HC, ME, and HE respectively. HR was significantly elevated in both exercise conditions. During the acute post exercise period, HR in HE was elevated above MC, ME and HC (p < 0.05). RT was elevated in both exercise conditions during and post exercise. The present data indicate that heat stress does not have a significant effect on the magnitude or duration of EPOC.School of Physical Education
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Shi, Xiaocai. "Effect of sodium and water intake on plasma aldosterone during prolonged exercise in warm environment." Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/722232.
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Eight well-trained male and female cyclists were studied to determine the effect of sodium and/or water intake on plasma aldosterone during six hours of cycling (55% VO2max) in a warm environment (Tdb = 350C WBGT = 30°C). Each subject randomly completed three trials (water = W; saline = S and no fluid = NF) at one week intervals. Venous blood samples were obtained before dehydration, at 2, 4, 5 and 6 hours during exercise, and also after dehydration. Plasma samples were analyzed for hemoglobin, sodium, potassium, aldosterone and osmolality. Sweat and urine samples were also collected and analyzed for sodium content. Plasma volume based on hemoglobin decreased significantly ( P < 0.01 ) at 15 min in all three trials (Trial W = -7.6%±1.12%; Trial S = -8.6%±1.42% and Trial NF = -6.7%±0.88%) and continued to decrease significantly in Trial NF during exercise ( -10.99% ± 1.3% at the 2th hr; -15.5% ±1.3% at the 4th hr and -16.8%±1.32% at the 5th hr).No significant differences were found betwee trials. Plasma sodium concentration [Na+] decreased over time in Trials W and S and increased in Trial NF due to plasma volume loss. Significant differences in [ Na+ ] were found between Trial NF and Trials W or S. Plasma sodium [Na+ ] adjusted by plasma volume change decreased significantly at 2 hours ( P < 0.01) in the three trials. Average total sodium content of plasma decreased by 125.9 mEq during Trial S, 223.1 mEq during Trial W and 147.1 mEq during Trial NF. Plasma potassium increased significantly (P < 0.01) at 2 hours in all three trials. Plasma osmolality increased significantly (P < 0.01) during prolonged exercise (Trial W = 287.1±2.4 mEq/l; Trial S = 289.4±1.17 mEq/1 and Trial NF = 306±1.6 mEq/1). No significant differences were found between Trials W and S although osmolality was lower in Trial W than in Trial S. A significant difference in osmolality was obtained between Trial NF and Trials W and S (P < 0.01). Plasma aldosterone increased significantly (P < 0.01) during exercise and decreased after exercise. No significant differences existed between Trials W and S although aldosterone levels were lower in Trial S than in Trial W. However, a significant difference was found between Trial NF and Trials W or S. The results of this study suggest that plasma aldosterone has an inverse relationship with plasma volume changes and total sodium concentrations. An increase in plasma potassium and a decrease in plasma sodium during prolonged exercise in a warm environment significantly enhanced plasma aldosterone concentration. The intake of water significantly decreased plasma aldosterone during prolonged exercise in a warm environment, but the intake of sodium had no significant effect in this study.School of Physical Education
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Majewicz, Jonathan. "The effect of vitamin E and vitamin C on the differential gene expression in monocytes and endothelial cells." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434331.
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Heyns, Gerhardus Johannes. "Influence of macro- versus microcooling on the physiological and psychological performance of the human operator." Thesis, Rhodes University, 1995. http://hdl.handle.net/10962/d1016247.
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This study evaluated the effect of a macro- versus a microcooling system on the cognitive, psychomotor and physiological performance of human operators. Male subjects (n = 24) were acclimatized for four days and then subjected to three different environmental conditions: hot ambient (40°C; 40% RH), microcooling and macrocooling. Each environmental condition was repeated twice; once under a rest condition and once while simulating a physical workload of 40 W. Four performance tests (reasoning, eye-hand coordination, memory, reaction time) were conducted once every hour for four hours. Five physiological measurements, viz rectal temperature, skin temperature, heart rate, total sweat loss and sweat rate, were taken. A significant difference existed between the physiological responses under the hot ambient condition and both cooling conditions. For all five physiological parameters he human operator benefitted substantially whatever the cooling condition. The psychological performance results indicated a greater benefit under the cooling conditions, though various external factors may have influenced responses. User perception showed that macrocooling was perceived to be the optimal method of cooling. The results showed that there was no difference in the extent to which both rectal temperature and heart rate (for rest and work conditions) decreased over the 4-hour study period with micro- and macrocooling. In the baseline hot environment both increase. Sweat rate was lowest when resting or working in a microcooled environment and at its highest in the hot baseline environment. Mean skin temperature was lowest (for rest and work conditions) with microcooling and highest in the hot baseline environment. Reaction time and memory/attention were the same under all three environmental conditions. Eye-hand coordination was better with cooling than without, but did not differ between the two cooling conditions. Reasoning ability was poorest under the hot baseline condition and best in the macrocooled environment. User perception showed that the subjects found macrocooling highly acceptable. Microcooling was found to be uncomfortable, particularly because cold air (18 - 21°C) entered the jacket at one point which caused numbness of the skin at that point. Jackets did not always fit subjects well and the umbilical cord restricted free movement.
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Loewen, Anisa Joy. "Optimizing the loading of vitamin A and vitamin D into re-assembled casein micelles and investigating the effect of micellar complexation on vitamin D stability." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50865.
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Food products may be fortified with vitamins A and D as public health intervention strategies. However, vitamin instability is a problem during storage before and after addition to foods. Re-assembled casein micelles (rCM) are reported to be effective carriers of hydrophobic compounds providing enhanced stability. The aim of this research was to form rCM with high loading of vitamin A palmitate (VA) or vitamin D₃ (VD). The protection given to VD by rCM was compared to that given by the controls composed of the re-assembly components not in micellar form, and to commercial vitamin products (CWS D₃, AD premix). Stability was investigated during storage of dry powders and of fortified skim milk exposed to light.
Response surface methodology was employed to ascertain the influence of phosphate, citrate and calcium on vitamin loading during CM re-assembly, and to identify optimal vitamin loading conditions. Average optimal VD loading of 14.0 or 15.1 mg VD/g casein was found at 4.9 or 10.5 mM phosphate, 4.0 mM citrate and 26.1 mM calcium, respectively. VA loading was optimal at 9.7 mM phosphate, 5.5 mM citrate and 30.0 mM calcium, resulting in 14.7 mg VA/g casein. Significantly more vitamin was retained in VD-rCM powders than control powders during storage at 37°C and 75% relative humidity for 48 and 72 hours. Additionally, loss of VD was not significantly different in VD-rCM powders compared to CWS D₃ during storage at 37°C and 75% relative humidity. Significantly more VD was retained in VD-rCM powders than control powders when stored at ambient temperature and humidity for up to 42 days. Retention of VD in skim milk fortified using different formulations and exposed to light for 21 days conformed to the following order: CWS D₃ > VD-rCM L, CD > AD premix. In conclusion, response surface methodology was an effective tool to optimize vitamin loading of rCM. Stability of VD was improved by incorporation into rCM for some storage conditions. Protection may depend on the physical state of the VD-rCM and on the applied stress.Land and Food Systems, Faculty of
Graduate
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Morgan, Michael J. "Opioid-dopamine interactions in analgesia in the formalin test." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74326.
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Controversy exists concerning the role that dopamine plays in analgesia. In the present studies, dopamine agonists produced analgesia, and D-amphetamine potentiated morphine analgesia, while treatment with 6-hydroxydopamine or mixed or selective D1 and D2 dopamine receptor antagonists attenuated or abolished morphine and D-amphetamine-induced analgesia, in the formalin test. Furthermore, microinjection of morphine into the ventral tegmental area (VTA) and ventral striatum produced analgesia, while intra-VTA microinjection of naloxone methylbromide antagonized the analgesia produced by systemic morphine, in the formalin test. In contrast, similar manipulations of dopamine had little or no effect in the tail flick test. Thus, dopamine appears to play a facilitatory role in formalin test analgesia, and there appear to be fundamental differences between the formalin and tail flick tests and parallels between the role of dopamine in the formalin test and in clinical pain, the vocalization after-discharge test and reward.
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Poirier, Patrick. "Effect of chronic stress on prefrontal cortical function." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86861.
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The prefrontal cortex (PFC) is a brain region thought to mediate cognitive functions such as working memory. Chronic stress has been shown to reduce working memory. In this thesis study, the effect of chronic stress on PFC functions was assessed in adult rats.First, contrary to previous evidences, chronic stress induces working memory performance alterations differentially in two populations of rats. One group displayed a decrease of performance only at 30 second delay, while the other had a decrease and increase at 0 and 30 seconds respectively.
Then, the effect of chronic stress on synaptic plasticity induction in the hippocampus-PFC network was investigated. High-frequency tetanic stimulation (HFS) of the dorsal hippocampus that induced long-term potentiation (LTP) in the prelimbic and infralimbic cortex in normal conditions was unable to induce LTP after chronic stress in the infralimbic cortex, whereas long-term depression (LTD) instead of LTP was induced in the prelimbic cortex.
Given that synaptic plasticity has been shown to depend on NMDA receptors in the PFC, NMDA subunit expressions before and after chronic stress was examined. There was a decrease of NR1 subunits expression in the prelimbic, but not infralimbic cortex. In contrast, the NR2A/NR2B ratio was increased in the infralimbic, but not prelimbic cortex. These results suggest that chronic stress disrupts PFC functions through dynamic modulation of distinct neural networks within the PFC.
Le cortex préfrontal (PFC) est une région du cerveau qui contrôle les fonctions cognitives comme la mémoire de travail. Dans cette thèse, l'effet du stress chronique sur des fonctions du PFC a été analysé chez des rats adultes.
Premièrement, les performances de la mémoire de travail ont été mesurées avant et après exposition au stress chronique. Nous avons constaté que le stress chronique induit des changements de performances de la mémoire de travail différemment selon deux populations de rats. Une des populations a démontré une diminution de performance seulement à 30 secondes de délai. Au contraire, l'autre a démontré une diminution de performance à 0 seconde et une amélioration de performance à 30 secondes.
En plus, nous avons évalué l'effet du stress chronique sur l'induction de la plasticité synaptique dans le réseau reliant l'hippocampe au PFC. Dans les conditions initiales, une stimulation tétanique à haute fréquence (HFS) dans l'hippocampe dorsal provoquait une potentialisation à long terme (LTP) dans le cortex prélimbique et infralimbique Or après exposition au stress chronique, une stimulation tétanique à haute fréquence n'a pas entraîné de potentialisation à long terme dans le cortex infralimbique. De plus, une exposition au stress chronique a provoqué l'apparition dans le cortex prélimbique d'une dépression à long terme (LTD) plutôt qu'une potentialisation à long terme.
Étant donné que la plasticité synaptique dépend des récepteurs de NMDA dans le PFC, nous avons examiné l'expression de sous-unité de NMDA avant et après exposition au stress chronique. En accord avec les changements synaptiques distincts de plasticité entre le cortex prélimbique et infralimbique après exposition au stress chronique, nous avons observé que l'expression de la sous-unité NR1 a diminué dans le prélimbique, mais non dans l'infralimbique. En revanche, le ratio de NR2A/NR2B a augmenté dans le cortex infralimbique, mais non dans le prélimbique. Ces résultats suggèrent que le stress chronique perturbe les fonctions du PFC par la modulation dynamique des réseaux distincts neurologiques dans le PFC.
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Dalal, Suntanu. "Amphetamine drugs potentiate morphine analgesia in the formalin test." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55488.
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There has been a great deal of research investigating drug combinations which can increase analgesia. A number of studies have been conducted with one particular combination--opioids combined with the amphetamine drugs. Despite the existing literature, this combination is rarely used in clinical practice. One purpose of this thesis is to review the literature pertaining to the opioid-amphetamine combination. Another purpose of this thesis is to investigate whether dextroamphetamine sulfate ($ circler$Dexedrine) can potentiate morphine sulfate analgesia in rats in the formalin test (Experiment 1). To investigate whether these results can be generalized to another psychostimulant, methylphenidate hydrochloride ($ circler$Ritalin) is used in Experiment 2. Methylphenidate has been chosen instead of another amphetamine drug because it is currently being used in clinical studies without supporting evidence from animal studies. The results of the two experiments indicate that low doses of d-amphetamine and methylphenidate can potentiate the analgesic effects of morphine.
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McCann, Mella Elizabeth. "Effect of vitamin D₃ and two low-calcemic vitamin D₃ analogues on osteopontin (OPN) - mediated neoplastic transformation." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426690.
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El, Fakhri Nagla. "Effect of vitamin D supplementation on bone status, glucose homeostasis and immune function in children with vitamin D deficiency." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7555/.
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Background: Between 1961-1971 vitamin D deficiency was recognized as a public health issue in the UK, because of the lack of effective sunlight and the population mix [1, 2]. In recent years, health care professionals have cited evidence suggesting a re-emergence of the vitamin D deficiency linked to a number of health consequences as a concern [3-6]. Evidence from observational studies has linked low vitamin D status with impairment in glucose homeostasis and immune dysfunction [7-9]. However, interventional studies, particularly those focused on paediatric populations, have been limited and inconsistent. There is a need for detailed studies, to clarify the therapeutic benefits of vitamin D in these important clinical areas. Objective: The aims of this PhD thesis were two-fold. Firstly, to perform preliminary work assessing the association between vitamin D deficiency and bone status, glucose homeostasis and immune function, and to explore any changes in these parameters following short term vitamin D3 replacement therapy. Secondly, to assess the effectiveness of an electronic surveillance system (ScotPSU) as a tool to determine the current incidence of hospital-based presentation of childhood vitamin D deficiency in Scotland. Methods: Active surveillance was performed for a period of two years as a part of an electronic web-based surveillance programme performed by the Scottish Paediatric Surveillance Unit (ScotPSU). The validity of the system was assessed by identifying cases with profound vitamin D deficiency (in Glasgow and Edinburgh) from the regional laboratory. All clinical details were checked against those identified using the surveillance system. Thirty-seven children aged 3 months to 10 years, who had been diagnosed with vitamin D deficiency, were recruited for the bone, glucose and immunity studies over a period of 24 months. Twenty-five samples were analysed for the glucose and bone studies; of these, 18 samples were further analysed for immune study. Treatment consisted of six weeks taking 5000 IU units cholecalciferol orally once a day. At baseline and after completion of treatment, 25 hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH), alkaline phosphatase (ALP), collagen type 1 cross-linked C-telopeptide (CTX), osteocalcin (OCN), calcium, phosphate, insulin, glucose, homeostasis model assessment index, estimated insulin resistance (HOMA IR), glycated hemoglobin (HbA1c), sex hormone binding globulin (SHBG), lipids profiles, T helper 1 (Th1) cytokines (interleukin-2 ( IL-2), tumor necrosis factors-alpha (TNF-α), interferon-gamma (INF-γ)), T helper 2 (Th2) cytokines (interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-6 (IL-6)), T helper 17 (Th17) cytokine (interleukin-17 (IL-17)), Regulatory T (Treg) cytokine (interleukin-10 (IL-10)) and chemokines/cytokines, linked with Th1/Th2 subset balance and/or differentiation (interleukin-8 (IL-8), interleukin-12 (IL-12), eosinophil chemotactic protein ( EOTAXIN), macrophage inflammatory proteins-1beta (MIP-1β), interferon-gamma-induced protein-10 (IP-10), regulated on activation, normal T cell expressed and secreted (RANTES), monocyte chemoattractant protein-1(MCP-1)) were measured. Leukoocyte subset analysis was performed for T cells, B cells and T regulatory cells and a luminex assay was used to measure the cytokiens. Results: Between September 2009 and August 2011, 163 cases of vitamin D deficiency were brought to the attention of the ScotPSU, and the majority of cases (n = 82) were reported in Glasgow. The cross-validation checking in Glasgow and Edinburgh over a one-year period revealed only 3 (11%) cases of clearly symptomatic vitamin D deficiency, which had been missed by the ScotPSU survey in Glasgow. While 16 (67%) symptomatic cases had failed to be reported through the ScotPSU survey in Edinburgh. For the 23 children who are included in bone and glucose studies, 22 (96%) children had basal serum 25(OH)D in the deficiency range (< 50 nmol/l) and one (4%) child had serum 25(OH)D in the insufficiency range (51-75 nmol/l). Following vitamin D3 treatment, 2 (9%) children had final serum 25(OH)D lower than 50 nmol/l, 6 (26%) children had final serum 25(OH)D between >50-75 nmol/l, 12 (52%) children reached a final serum 25(OH)D >75-150 nmol/l and finally 3 (13%) exceeded the normal reference range with a final 25(OH)D >150 nmol/l. Markers for remodelling ALP and PTH had significantly decreased (p = 0.001 and <0.0001 for ALP and PTH respectively). In 17 patients for whom insulin and HOMA IR data were available and enrolled in glucose study, significant improvements in insulin resistance (p = 0.04) with a trend toward a reduction in serum insulin (p = 0.05) was observed. Of those 14 children who had their cytokines profile data analysed and enrolled in the immunity study, insulin and HOMA IR data were missed in one child. A significant increase in the main Th2 secreted cytokine IL-4 (p = 0.001) and a tendency for significant increases in other Th2 secreted cytokines IL-5 (p = 0.05) and IL-6 (p = 0.05) was observed following vitamin D3 supplementation. Conclusion: An electronic surveillance system can provide data for studying the epidemiology of vitamin D deficiency. However, it may underestimate the number of positive cases. Improving vitamin D status in vitamin D deficient otherwise healthy children significantly improved their vitamin D deficient status, and was associated with an improvement in bone profile, improvements in insulin resistance and an alteration in main Th2 secreting cytokines.
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Pears, Jamie Andrew. "Investigation of the physiological basis of the BOLD effect." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394843.
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Van, Rooyen Megan Lynne. "The effect of combined vitamin E succinate and ascorbic acid supplementation on growth and cyclooxygenase expression in murine melanoma (BL6) cells." Thesis, Rhodes University, 1999. http://hdl.handle.net/10962/d1004041.
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This thesis examines the effect of combined vitamin E succinate and Asc supplementation on the in vitro growth of a non-malignant monkey kidney (LLCMK) and a malignant melanoma (BL6) cell line, with nutritional concentration ranges of 5-20µg/ml and 25-50µg/ml respectively. Vitamin E and C are thought to interact synergistically to inhibit tumour cell growth by virtue of their antioxidant properties, whereby they quench free radicals and terminate lipid peroxidation. Furthermore vitamin E and C are thought to modulate the biosynthetic pathways in arachidonic acid metabolism at a number of different points. This may also offer a means of regulating tumour cell growth. It is well documented that vitamin E and C are distributed in the lipid and aqueous phases in the cell respectively. However, the cells need to obtain the vitamins from the environment in which they are found in order to exert a growth inhibitory effect. Supplementation of combined vitamin E succinate and Asc on BL6 and LLCMK cells resulted in a significant increase in LLCMK cell growth, and a significant decrease in cell growth was observed in BL6 cells. Vitamin E succinate in its esterified form cannot function as an antioxidant and requires the cleavage of the succinate to become an active antioxidant. The metabolism of vitamin E succinate to form free vitamin E in LLCMK and BL6 cells resulted in the cleavage of the succinate group from the vitamin E molecule in BL6 cells only, thus suggesting that an esterase may be present in BL6 cells. This would allow for a synergistic interaction between the two vitamins. The arachidonic acid cascade generates a family of bioactive lipids that modulate diverse physiological and pathological responses including tumour growth and promotion. The enzyme prostaglandin endoperoxide synthase (PGHS) or cyclooxygenase (Cox) is the key enzyme in the biosynthetic pathway leading to the formation of prostaglandins. Two enzyme isoforms of Cox have been identified, Cox 1 and Cox 2. Supplementation with vitamin E succinate and Asc at a combination 20:25µg/ml respectively resulted in a trend of increasing Cox activity over 12 hours suggesting that vitamin E and Asc have a stimulatory effect on Cox activity in BL6 cells. The inhibitors of Cox 2, dexamethasone, showed a decreasing trend in Cox activity at the 20:25µg/ml combination, while cycloheximide showed an initial stimulatory effect and then a gradual decrease in Cox activity. The elimination of the Cox activity by dexamethasone suggests that transcriptional regulation may be occurring in BL6 cells. We examined by Northern blot analysis whether combined supplementation of vitamin E succinate and Asc caused an elevation of Cox 2 RNA expression in BL6 cells. An inducible effect of Cox 2 was observed after 2 hours of supplementation with a combination of vitamin E succinate and Asc in BL6 cells, however the results are inconclusive and further studies are required to substantiate this finding.
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Chen, Qixuan, and 陳起萱. "Anti-obesity effect of bitter melon (Momordica charantia)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31048778.
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Carrithers, John A. "Effects of post-exercise carbohydrate-protein feedings on muscle glycogen restoration." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1133741.
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The purpose of this investigation was to determine the effects of post-exercise carbohydrate-protein feedings on muscle glycogen restoration following exhaustive cycle ergometer exercise. Seven male collegiate cyclist (age=25.6±3.3y, ht.=180.9±8.5cm, wt.=75.4±10.7kg, VO2max=4.20±0.4 1•miri 1) performed three trials, each separated by -lwk, 1) 100% (x-D glucose (CHO), 2) 70% carbohydrate-20% protein-10% fat (CHOPRO), and 3) 86% carbohdyrate-14% amino acid (CHO-AA). All feedings were eucaloric, based upon 1.0 g•kgb.W.'1•hr"1 of carbohydrate, and administered every half hour during a four hour muscle glycogen restoration period in an 18% wt./vol. solution. Muscle biopsies were obtained immediately and four hours post exercise. Following the exhaustive exercise and every half hour for four hours a blood sample was drawn. Muscle glycogen concentrations increased 53%, 47%, and 57% for the CHO, CHO-PRO, and CHO-AA feedings, respectively, however no differences among the feedings were apparent in muscle glycogen restoration. The plasma glucose and insulin concentrations demonstrated no differences throughout the restoration period among the three feedings. These results suggest that muscle glycogen restoration does not appear to be enhanced with the addition of either protein or amino acids to an eucaloric carbohydrate feeding following an exhaustive cycle exercise. However, it appears that if adequate amounts of carbohydrates are consumed (greater than 0.70 g•kgb,W,."'•hf' carbohydrate) following exhaustive exercise, maximal muscle glycogen restoration occurs.School of Physical Education
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Hawley, John A. "The effect of treadmill running and swimming on citrate synthase activity and glycogen levels in the rat." Virtual Press, 1986. http://liblink.bsu.edu/uhtbin/catkey/450972.
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Thirty-eight female Wistar rats were studied to determine the response of citrate synthase (CS) and glycogen (GLY) to two similar programs of endurance training. Animals were randomly assigned to one of three groups: run-trained (RUN), swim-trained (SWIM) or sedentary control (CON). The treadmill trained animals ran at a speed of 27 m/min. up an eight degree incline. The swim-trained animals swam with 2% of body weight attached to their tails. The duration of the exercise protocols was 2 hours/day, the frequency 5 days/week and the length of the training regimen was 10 weeks. Liver GLY content (mmoles/g) for the exercise trained groups was significantly higher (p < 0.01) than CON. There were no significant differences between RUN and SWIM animals in the GLY levels of the hindlimb muscles. The GLY levels of the forelimb muscles were significantly greater (p0.01) in the SWIM animals compared to the RIJN animals, apart from the pectoralis (EEC). The CS activity in the soleus (SOL) and red -vastus (RV) of the RUN animals was significantly larger (p <; 0.01) than SWIM. The plantaris (PLANT) of the SWIM animals had significantly greater CS activity than the RUN animals. In the forelimb muscles, only -the deltoid (DEL) of the SWIM group was higher in CS activity than the RUN groups. The results of this study indicate that the mechanisms responsible for increased GLY storage in skeletal muscle are under independent control to those factors governing the changes in the oxidative enzyme CS. Differences in muscle GLY levels and CS activity between RUN and SWIM rats can be explained by contrasting mechanics in these two (nodes of exercise and the resulting fiber recruitment patterns.
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Amend, Valerie A. "Implications of beverages and physical activity on hot flashes in menopausal women." CardinalScholar 1.0, 2009. http://liblink.bsu.edu/uhtbin/catkey/1538075.
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The purpose of this research study was to examine the effects of consumption of beverages (caffeinated and alcoholic) and physical activity on the frequency and severity of hot flashes in peri-menopausal, menopausal, and post-menopausal women by conducting an on-line survey of women over the age of 40 employed at a Midwestern University. One-hundred ninety-six women participated in this study. Majority of participants were age 50-59 (n=104, 53.1%), and were in the naturally post-menopausal reproductive stage (n=81, 41.3%). Overall, results revealed that the effects of self-reported physical activity, average daily caffeine and alcohol intake were not significant in predicting the frequency of hot flashes (R2=.043, F(6, 184) = 1.39, p= .221). However, results revealed a small, but statistically significant effect of physical activity, caffeine, and alcohol intake on severity of hot flashes (R2=.068, F(6,180) = 2.195, p = .046). Additionally, relatively more participation in aerobic physical activity increased frequency of hot flashes (p= .031); while higher intensity of aerobic physical activity had an inverse relationship on both frequency and severity of hot flashes (p=.011, p=.003, respectively).Department of Family and Consumer Sciences
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Mahabeer, Rajeshree. "An investigation into the effects of inorganic toxins and tryptophan metabolites on the forebrain cholinergic system and the pineal gland of the rat." Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1004078.
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As soon as the building of the body is completed, the ageing process begins. In the natural course of events, the functioning of some organ systems finally ebbs below the threshold necessary to maintain the body, resulting in death. This occurrence is relatively rare, because diseases superimpose themselves upon the ageing process, bringing premature death resulting from pathological causes. This study focused on the cholinergic system of the rat forebrain. The cholinergic neurons in the brain are said to be involved in memory and learning, and a decrease in the activity of its enzymes has been reported in certain diseases, such as Alzheimer's disease. In the present study, the in vitro effects on the cholinergic system, of aluminium and mercury and tryptophan metabolites, kynurenic acid and quinolinic acid, are determined. Aluminium has been considered as a possible factor in Alzheimer's disease. Mercury in high concentrations is toxic, and its use in amalgam for dental treatment is under consideration with regard to its possible role in promoting neurological disease. The tryptophan metabolites increase in the brain with age and may have a role in pathological diseases. Quinolinic acid, when administered in toxic concentrations produces a possible model for Huntington's disease. This study investigated the effects of the above mentioned toxins on: (1) The synthesis of acetylcholine by choline acetyltransferase; (2) The specific binding of acetylcholine muscarinic receptors; (3) The degradation of acetylcholine by acetyl cholinesterase, Choline acetyltransferase activity did not change in the presence of aluminium chloride, kynurenic acid and quinolinic acid from 1 nM to 1 mM. Mercuric chloride had no significant effect on the enzymes activity from a concentration of 1 nM- 1 pM. At 10 pM there was a significant decrease in cholineacetyltransferase activity (P < 0.001). Enzyme activity continued to decrease at 100 pM (P < 0.0002). At 1 mM, enzyme activity was virtually non existent (P < 0.0001). Acetyl cholinesterase activity was not affected by aluminium chloride, kynurenic acid and quinolinic acid. Mercuric chloride from 1 pM - 1 mM significantly reduced the enzyme activity (P < 0.05). The binding of the antagonist, [³H] quinuclidinyl benzilate (QNB), to acetylcholine muscarinic receptors, revealed that aluminium chloride did not affect the binding of the antagonist, in the concentration range of 1 nM - 100 pM, to the receptors. At 1 mM, aluminium chloride appears to increase the sensitivity of the receptors for the ligand (P < 0.01). Mercuric chloride also does not appear to have any significant effect on receptor binding in this range. However, at 1 mM there appears to be a very significant decrease in receptor binding (P < 0.01). This decrease may be attributed to the interaction of mercury with the sulfhydryl groups in muscarinic receptors. Kynurenic acid had no effect on the receptor binding. Quinolinic acid, in the concentration range from 10 nM - 1 mM increased the binding ofthe receptor to [3Hi QNB significantly (P < 0.001). The study also investigated the effect of the tryptophan metabolites of the kynurenine pathway on pineal indole metabolism. The kynurenine pathway is a major route of tryptophan metabolism in the pineal gland, along with indole metabolism. Investigations showed that kynurenic acid produced a decrease in N-acetylserotonin concentrations ( P < 0.001) and melatonin concentrations (P < 0.003). Further experiments using quinolinic acid produced a similar decrease in N-acetylserotonin (P < 0.001) and melatonin (P < 0.015). A decrease was also noted in the level of 5-methoxytryptophol (P < 0.0005). These findings suggest that aluminium chloride, kynurenic acid and quinolinic acid have no possible role in the decrease of activity of cholinergic enzymes which is observered in diseases such as Alzheimer's disease. The results regarding the effect of mercury chloride on the cholinergic system suggest that low exposure to the toxin will not adversely effect the enzymes. The decrease in N-acetylserotonin and melatonin concentrations reported here, may be a result of kynurenic acid and quinolinic acid having an inhibitory effect on the enzyme, serotonin Nacetyltransferase, which is responsible for the conversion of serotonin to N-acety/serotonin.
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Farley, Sherry Mae. "Vitamin E and K interactions : investigating mechanisms of reduced vitamin K status in response to excess vitamin E." Thesis, 2012. http://hdl.handle.net/1957/36141.
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The primary goal of my studies was to elucidate the mechanisms for the well-recognized interaction between two nutrients, vitamins E and K. The outcomes from my studies assess mechanisms for adverse effects of vitamin E and provide novel information on mechanisms for vitamin K homeostasis. These findings will provide information relevant for assessing optimal intakes of vitamins E and K.
This dissertation presents studies aimed at evaluating three different mechanisms by which vitamin K status could be decreased by increases in whole body vitamin E concentrations in rats supplemented with vitamin E by subcutaneous injections (100 mg α-tocopherol (α-T)/ kg body weight per day), the model system developed in the Traber lab. The tested mechanisms by which vitamin E leads to reduced vitamin K status were: 1) increasing vitamin K metabolism, 2) decreasing menaquinone-4 (MK-4) synthesis from dietary phylloquinone (PK) and 3) potentiating vitamin K excretion through xenobiotic pathways.
Two approaches were undertaken to evaluate the hypothesis that vitamin E increases vitamin K metabolism. In Aim 1.1, the in vitro omega-hydroxylation of vitamin K by human cytochrome P450 CYP4F2 (expressed in insect microsomes) was tested because CYP4F2 is considered the limiting step in the catabolism of both vitamins. Chapter 2 shows that CYP4F2 more rapidly hydroxylated vitamin K compared with vitamin E. Moreover, vitamin E did not stimulate vitamin K metabolism in vitro. Thus, it is unlikely vitamin E stimulates vitamin K metabolism in vivo by direct interaction with the CYP4F2 enzyme-substrate complex. In Aim 1.2, the in vivo urinary and biliary excretion of vitamin K metabolites was investigated. Chapter 3 shows that α-T-injected rats significantly increased urinary excretion of vitamin E catabolites, but no increases in urinary vitamin K catabolites were found. Chapter 4 shows that α-T-injected rats increased biliary excretion of 5C-aglycone, a major vitamin K catabolite shared by MK-4 and PK. However, the overall in vivo excretion of vitamin K catabolites was not changed when urinary excretion was also taken into account.
Aim 2 evaluated the hypothesis that α-T interferes with the conversion of PK to MK-4 because α-T and PK have similar side-chains. In Aim 2.1, conversion of PK or MN to MK-4 was tested in vivo. Rats were fed semi-purified diets containing equimolar concentrations of either PK or MN for 10 days, then α-T injections were undertaken. Chapter 3 shows that extra-hepatic tissues from α-T injected rats contained significantly lower MK-4 concentrations irrespective of whether the rats were fed PK or MN. These findings show that if vitamin E is interfering with the metabolic mechanism of MK-4 synthesis, then it is not specific to the cleavage of PK's side chain. In Aim 2.2, conversion of deuterium-labeled PK (d₄-PK) to d₄-MK-4 was used to evaluate the extra-hepatic tissue uptake of d₄-PK in α-T-injected rats. Rats were fed semi-purified diets containing equimolar concentrations of d₄-PK similar to my previous study for 10 days then α-T injections were undertaken for 7 days. Chapter 5 shows that total (labeled and unlabeled) vitamin K concentrations decreased in extra-hepatic tissues from α-T injected rats fed d₄-PK. Both d₄-MK-4 and d₄-PK concentrations decreased, suggesting that MK-4 concentrations were dependent upon those of d₄-PK. These findings suggest that PK, and not MN, is the primary substrate for MK-4 synthesis in extra-hepatic tissues. Moreover, both d₄-MK-4 and d₄-PK decreased in α-T-injected rats demonstrating that vitamin E's untoward effect on vitamin K status is likely a mechanism that is shared by both vitamin K forms and not specific to MK-4 synthesis. Recycling of vitamin K from the epoxide was not examined in this study and interference with the recycling mechanism for either PK or MK-4 in α-T injected rats has not been examined.
Vitamin E metabolism is greatly increased in α-T-injected rats by increasing various xenobiotic pathways. Thus, vitamin K status was hypothesized to decrease in α-T-injected rats as a result of the up-regulation of these pathways. As shown in Aim 1, urinary vitamin K metabolite excretion was not increased in α-T-injected rats. In Aim 3.1, the biliary excretion of vitamins E and K were examined to evaluate whether the increased expression in biliary transporters, such as MDR1, led to increased vitamin K and E excretion via the bile. Chapter 4 shows that α-T increased in bile over the week of vitamin E injections and α-CEHC was the major vitamin E form excreted in bile. Although biliary PK secretion was unchanged and biliary MK-4 was undetectable, increased excretion of a major catabolite of both PK and MK-4, 5C-aglycone, was observed. In Aim, 3.2, the gene expression of enzymes and transporters in liver and extra-hepatic tissues as mechanisms involved in regulating their concentrations in these tissues was assessed. In Chapters 3 and 5, increased expression of biliary transporters were observed, one of which is known to bind the vitamin K intermediate MN as its substrate. It is possible other vitamin K catabolites, in addition to 5C-and 7C-aglycone, may have been excreted that were unaccounted for, e.g. MN or vitamin K epoxide metabolites.
In summary, my studies have shown vitamin K status is decreased in α-T-injected rats because PK and MK-4 concentrations are decreased in many extra-hepatic tissues. Although metabolism of vitamin K was not stimulated in response to α-T injections, increased excretion of a vitamin K catabolite was measured in the bile; however it may not account for all of the vitamin K loss observed in tissues. Alternatively, transport of PK and MN to extra-hepatic tissues or MK-4 recycling may have been inhibited in response to vitamin E. Further studies are needed to distinguish between these mechanisms.Graduation date: 2013
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Huang, Ying-Hui. "The effect of two levels of glucose ingestion on plasma pyridoxal 5'-phosphate concentration." Thesis, 2000. http://hdl.handle.net/1957/26554.
Full textAbstract:
This study was designed to evaluate the effect of glucose on plasma pyridoxal 5'-
phosphate (PLP) concentration. The objective was to determine whether there was a
negative relationship between glucose ingestion and plasma PLP concentration and to
evaluate the possible mechanism of decreased PLP after acute glucose ingestion.
Seven healthy subjects (three males and four females) completed the oral glucose
tolerance test (OGTT) on three separate occasions over a period of three weeks. Each
week, subjects ingested the assigned solutions (a water solution with artificial sweetener
equivalent to 25g glucose, a 25g glucose or a 75g glucose load) in a randomized order.
Plasma PLP, pyridoxal (PL), 4-pyridoxic acid (4-PA), pyridoxine (PN), glucose, insulin,
alkaline phosphatase (AP) activity and red blood cell PLP concentrations were measured
at 0 (fasting) (TO), 1 (T1), 2 (T2) and 3 (T3) hours.
The mean vitamin B-6 intake based on two 3-day dietary records was 1.57 ± 0.34
mg/day. All subjects had normal glucose tolerance. There were gender differences
among the three solutions. Both the water solution and the 75g glucose load showed a significant decrease in the mean plasma PLP concentration was observed at T3 for males
and at T2 for females (p<0.05). An overall mean decrease of 20% (9nmol/L) and 15% (7
nmol/L) was observed for males and females, respectively, after the 75g glucose load.
The 25g glucose load resulted in a lower decrease in the mean plasma PLP concentration
at each time point compared with the 75g glucose load, but no significant difference was
found in the level of decrease between the two glucose loads.
Both genders had a non-significant increase in the mean plasma PL and PN
concentrations for the three solutions. Mean plasma 4-PA concentration was decreased at
T1 with the three solutions. There was no significant change in the plasma AP activity at
any time points after the three solutions. In addition, no significant increase in mean red
blood cell PLP concentration was observed at all time points after the three solutions.
This study found a negative relationship between glucose ingestion and plasma PLP
concentration. However, it did not provide clear evidence for the hypothesized
mechanism of the decreased plasma PLP concentration after acute glucose load. Further
studies are required to determine the mechanism by which glucose decreases plasma PLP
concentration.Graduation date: 2000
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Hopkins, Dawn Marie Weseli. "Inflammation, immune suppression, and iron status in endurance athletes and the effects of antioxidant supplementation." Thesis, 2003. http://hdl.handle.net/1957/31532.
Full textAbstract:
During extreme exercise, athletes experience increased inflammation that is
similar to the acute phase response. Endurance athletes, distance runners in
particular, are also more susceptible to compromised iron stores. This study
evaluated inflammation, immune function and iron status in athletes completing a
50K ultramarathon. Twenty-two well-trained distance runners, 11 males and 11
females, were randomized in a double blind manner into--1) those who consumed
300 mg vitamin E and 1000 mg vitamin C (500 mg twice daily) or 2) placebos--for
six weeks before and one week following a 50K ultramarathon race. Blood
samples were obtained on 13 separate occasions throughout the study: before
supplementation, during supplementation, the day before the race, pre-race, mid-race,
immediately post-race, 2 hours following the race, and daily for six days
following the race. Plasma levels of ascorbic acid and ��-tocopherol were measured
by HPLC with electrochemical detection. Inflammatory cytokines, interleukin-6
(IL-6), tumor necrosis factor-�� (TNF-��), and interleukin-1�� (IL-1��) were measured
using standard clinical assays. Each subject recorded immune function in an
activity log and incidence of illness was tabulated as number of days ill. Ferritin
was measured by enzyme immunoassay. Hemoglobin, hematocrit, and total-iron
binding capacity (TIBC) and serum total iron were analyzed by standard
procedures.
Plasma concentrations of ascorbic acid and ��-tocopherol increased
significantly in supplemented subjects (p<0.0001). Although the ultramarathon
race elicited an inflammatory response, antioxidant supplementation did not alter
the responses of IL-6 and TNF-��, which both increased from pre-race to mid-race,
post- and post-2 h (Scheffe post-hoc analysis, p<0.0001) and returned to pre-race
concentrations by 1 day after the race. Male supplemented subjects had lower IL-1��
concentrations compared to females consuming the supplement or to males
consuming the placebo (ANCOVA, gender/time/treatment interaction; p<0.01) at
mid-race (p<0.05 females, p<0.005 males), post 1 and 2 days (all p<0.002).
Males had significantly higher ferritin levels than the female subjects (ANOVA, p<0.0001); supplementation resulted in lower ferritin concentrations at post-5 days
(p<0.02, ANCOVA treatment time interaction, p<0.005). Supplementation did
not reduce the days illness among those consuming antioxidants compared to those
consuming the placebos. Ferritin not only increases during inflammation, it also is a measure of iron
stores. Females had significantly lower levels of iron than the male subjects for
each of the iron parameters measured (hemoglobin and hematocrit both p<0.0001,
ferritin p<0.001, TIBC p<0.02) excluding serum total iron. The ferritin
concentrations measured in the women were indicative of depleted iron stores (<12
��g/l), and antioxidant supplementation increased hematocrit levels in the female
subjects (p<0.05). This investigation indicates that female distance runners need
to be aware of an increased susceptibility to iron depletion compared to their male
counterparts. Antioxidant supplementation improved hematocrit levels (p<0.05)
among female runners and may improve iron status among females with depleted
stores.
Although other investigations have suggested that antioxidant vitamins
decrease exercise induced inflammation, no profound benefit of supplementation
was found in this investigation though a response similar to the acute phase
response was elicited by the ultramarathon race. Improvements in IL-i and
ferritin in response to antioxidant supplementation may indicate that the
supplementation was beneficial, but more research is needed to draw definitive
conclusions.Graduation date: 2003
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Beilstein, Michael A. "Effect of vitamin B-6 status on Selenium metabolism in the rat." Thesis, 1990. http://hdl.handle.net/1957/25982.
Full text
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Wan, Daisy. "Effect of dietary ethanol and zinc on vitamin B-6 metabolism in the rat." Thesis, 1992. http://hdl.handle.net/1957/25987.
Full text