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1
Lough, Patricia Schechter. "Use of urine samples for ethanol analysis". CSUSB ScholarWorks, 1989. https://scholarworks.lib.csusb.edu/etd-project/446.
2
Abdelrazig, Salah M. A. "Mass spectrometry for high-throughput metabolomics analysis of urine". Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/30600/.
Abstract (sommario):
Direct electrospray ionisation-mass spectrometry (direct ESI-MS), by omitting the chromatographic step, has great potential for application as a high-throughput approach for untargeted urine metabolomics analysis compared to liquid chromatography-mass spectrometry (LC-MS). The rapid development and technical innovations revealed in the field of ambient ionisation MS such as nanoelectrospray ionisation (nanoESI) chip-based infusion and liquid extraction surface analysis mass spectrometry (LESA-MS) suggest that they might be suitable for high-throughput metabolomics analysis. In this thesis, LC-MS and high-throughput direct ESI-MS methods using high resolution orbital trap mass spectrometer were developed and validated for untargeted metabolomics of human urine. Three different direct ESI-MS techniques were explored and compared with LC-MS: flow injection electrospray ionisation-MS (FIE-MS), chip-based infusion and LESA-MS of dried urine spots on a cell culture slide. A high-throughput sample preparation protocol was optimised using in-house artificial urine. Urine samples after consumption of green tea and healthy controls were used as a model to explore the performance and classification ability of the direct ESI-MS. High-throughput data pre-processing and multivariate analysis protocols were established for each method. The developed methods were finally applied for the analysis of clinical urine samples for biomarker discovery and to investigate the metabolic changes in osteoarthritis and malaria. Also, the methods were applied to study the effect of oligofructose diet on the gut microbial community of healthy subjects. The analytical performance of the methods for urine metabolomics was validated using quality control (QC) and principal component analysis (PCA) approaches. Rigorous validation including cross-validation, permutation test, prediction models and area under receiver operating characteristic (ROC) curve (AUC) was performed across the generated datasets using the developed methods. Analysis of green tea urine samples generated 4128, 748, 1064 and 1035 ions from LC-MS, FIE-MS, chip-based infusion and LESA-MS analysis, respectively. A selected set of known green tea metabolites in urine were used to evaluate each method for detection sensitivity. 15 metabolites were found with LC-MS compared to 8, 5 and 6 with FIE-MS, chip-based infusion and LESA, respectively. The developed methods successfully differentiated between the metabolic profiles of osteoarthritis active patients and healthy controls (Q2 0.465 (LC-MS), 0.562 (FIE-MS), 0.472 (chip-based infusion) and 0.493 (LESA-MS)). The altered level of metabolites detected in osteoarthritis patients showed a perturbed activity in TCA cycle, pyruvate metabolism, -oxidation pathway, amino acids and glycerophospholipids metabolism, which may provide evidence of mitochondrial dysfunction, inflammation, oxidative stress, collagen destruction and use of lipolysis as an alternative energy source in the cartilage cells of osteoarthritis patients. FIE-MS, chip-based infusion and LESA-MS increased the analysis throughput and yet they were able to provide 33%, 44% and 44%, respectively, of the LC-MS information, indicating their great potential for diagnostic application in osteoarthritis. Malaria samples datasets generated 9,744 and 576 ions from LC-MS and FIE-MS, respectively. Supervised multivariate analysis using OPLS-DA showed clear separation and clustering of malaria patients from controls in both LC-MS and FIE-MS methods. Cross-validation R2Y and Q2 values obtained by FIE-MS were 0.810 and 0.538, respectively, which are comparable to the values of 0.993 and 0.583 achieved by LC-MS. The sensitivity and specificity were 80% and 77% for LC-MS and FIE-MS, respectively, indicating valid, reliable and comparable results of both methods. With regards to biomarker discovery, altered level of 30 and 17 metabolites were found by LC-MS and FIE-MS, respectively, in the urine of malaria patients compared to healthy controls. Among these metabolites, pipecolic acid, taurine, 1,3-diacetylpropane, N-acetylspermidine and N-acetylputrescine may have the potential of being used as biomarkers of malaria. LC-MS and FIE-MS were able to separate urine samples of healthy subjects on oligofructose diet from controls (specificity/sensitivity 80%/88% (LC-MS) and 71%/64% (FIE-MS)). An altered level of short chain fatty acids (SCFAs), fatty acids and amino acids were observed in urine as a result of oligofructose intake, suggesting an increased population of the health-promoting Bifidobacterium and a decreased Lactobacillus and Enterococcus genera in the colon. In conclusion, the developed direct ESI-MS methods demonstrated the ability to differentiate between inherent types of urine samples in disease and health state. Therefore they are recommended to be used as fast diagnostic tools for clinical urine samples. The developed LC-MS method is necessary when comprehensive biomarker screening is required.
3
Cooper, Mark Thomas. "A chromatographic method for detecting phenolic metabolites of carbosulfan in urine". Thesis, Queensland University of Technology, 1989. https://eprints.qut.edu.au/35977/1/35977_Cooper_1989.pdf.
Abstract (sommario):
The inability of the conventional blood cholinesterase
test to reliably detect carbamate pesticide poisoning in
humans prompted the investigation of an alternative
surveillance method. Rapid, micro-scale sample treatment
procedures were developed to extract the phenolic
metabolites of carbosulfan from urine, convert these
compounds to their dinitrophenyl ether derivatives and
determine their concentrations quantitatively by nitrogen
selective gas-liquid chromatography. This method was
capable of detecting micro-gram levels of metabolites and
performed to an accuracy of<+/ 10% and precision of<
6% RSD.
In vivo experiments we re undertaken in which carbosul fan
was administered to laboratory rats and the effects of
dosage and sampling time on the level of phenolic
metabolites in urine were examined. These results
provide guidelines for human exposure however absolute
confidence in these thresholds will only occur when the
data base of human experience is collected and correlated
to metabolite levels in urine.
Urine samples were drawn and analyzed from potentially
exposed personnel handling carbosulfan and in all cases
no phenolic metabolites were detected.
4
Kirk, Jayne Marie. "Mass Spectrometric Analysis of Steroid Hormones for Application in Analysis of Bovine Urine". Thesis, University of York, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485830.
Abstract (sommario):
Analytical strategies for the identification and quantification of up to 14 androgenic steroids and up to 17 corticosteroids have been evaluated and applied to bovine urine. The two classes ofsteroid have been analysed both as the native species and as Girard P hydrazone derivatives. Triple quadrupole mass spectrometry, operated in multiple reaction monitoring mode, has permitted the development of methods that enable the simultaneous detection of a range ofandrogenic steroids and corticosteroids at the ng mL-1 level. For a non-targeted approach, screening for the presence of corticosteroids was performed on a time of flight mass spectrometer, where confirmation of the identities of corticosteroids was obtained from accurate mass information. Girard P hydrazone derivatives of androgenic steroids and corticosteroids are amenable to analysis by electrospray mass spectrometry. The presence of an ionic group at position C-3 ofthe steroids increases their response relative to the native species by up to 33 times for the androgenic steroids and up to 21 times for the corticosteroids. The derivatisation reaction has been shown to work effectively in bovine urine, with limits ofdetection determined as ::::; 1 ng mL-1 for both classes ofsteroid hydrazone. Ion trap mass spectrometry has proved to be an extremely powerful tool for the elucidation of dissociation pathways of steroids and their hydrazone derivatives. Analysis of androgenic steroids, androgenic steroid hydrazones and corticosteroid hydrazones using multistage tandem mass spectrometry has shown how the varying functionality of the steroids affects their dissociation pathways, and how comparisons between similar structures can aid the assignment of product ions. Multistage tandem mass spectrometry of the hydrazone derivatives provides a wealth of structure-specific product ions arising due to losses from either the steroid or hydrazine moiety, and detailed dissociation sequences have been established, enabling structure assignment. A complete method employing sample extraction and derivatisation followed by analysis using liquid chromatography-multistage tandem mass spectrometry has been developed to allow full characterisation and structure confirmation of the steroids present in urine.
5
Couchman, Lewis. "LC-MS/MS analysis of buprenorphine and norbuprenorphine in urine". Thesis, Queen Mary, University of London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511397.
6
Hassan, Syed Saeed-Ul. "Rapid immunological methods for analysis of dexamethasone in equine urine". Thesis, University of Sunderland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245822.
7
Allen, Robert Douglas III. "Development of an assay for the detection of cytomegalovirus in urine". Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/25410.
8
Chen, Hui-Chuen. "The urinary excretion of mercapturic acids in free-living adult males". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-12052009-020010/.
9
Hoang, Tiffany Truc. "Speciation and identification of low molecular weight organoselenium metabolites in human urine". Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/30671.
10
Stubbs, Christopher. "High performance liquid chromatographic analysis of erythromycin in serum and urine". Thesis, Rhodes University, 1985. http://hdl.handle.net/10962/d1004581.
Abstract (sommario):
Erythromycin, a macrolide antibiotic used mainly against gram-positive bacteria has been in clinical use since 1952 (1). Previous pharmacokinetic data published on this antibiotic have been derived predominantly from microbiological assay techniques. However, these techniques are relatively imprecise as well as being non-specific and extremely tedious to perform. A novel high performance liquid chromatographic analysis of erythromycin in human serum and urine using U.V. detection at 200 nm and/or electrochemical detection using both an amperometric and a coulometric electrochemical detector is presented. The method involves a solid phase extraction procedure followed by a simple phase separation step and chromatography on a reverse phase column. In order to select the optimum U.V. detector for this analysis, five "state of the art" detectors were compared in terms of their signal-to-noise ratios at U.V. wavelengths between 200 and 210 nm. A known metabolite des-N-methylerythromycin is readily detectable using U.V. detection, whilst another metabolite/degradation product anhydroerythromycin is not seen using U.V. detection but is readily observable using an electrochemical detector. The method has a limit of sensitivity of 0.25 μg/mL and 1.00 μg/mL in serum and urine respectively (U.V. detection) and is sufficiently sensitive to monitor serum and urine concentrations of erythromycin in man after administration of a single 500 mg erythromycin stearate tablet.KMBT_363
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11
West, Robert E. 1952. "Confirmation of urinary benzodiazepines by gas chromatography/mass spectrometry". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277228.
Abstract (sommario):
A new method is described for the quantitative analysis of urinary benzodiazepines by gas chromatography/mass spectrometry. Development work was aimed at satisfying federal requirements for methods used in forensic urine drug testing which have become the standard in the laboratory industry. Trimethylsilyl (TMS), tert-butyl-dimethylsilyl (TBDMS) and benzophenone derivatives were tested in the development of the new assay. TBDMS derivatives were found to be the most suitable for the analysis of six common benzodiazepine metabolites. Precision for all metabolites tested, as measured by the within run coefficient of variation, was less than 7% at 100 ng/ml (n = 15). Assay sensitivity varied with the specific analyte in the range of 5 to 10 ng/ml. Validation of the procedure included the reanalysis of benzodiazepine positive urine specimens obtained from a forensic drug testing laboratory and comparison of the results from the independent assays. These specimens were tested first by radioimmunoassay using a 100 ng/ml cutoff and then confirmed by GC/MS. Sensitivity was sufficient to confirm the presence of benzodiazepine metabolites in all specimens tested.
12
Rocha, Diogo Librandi da. "Desenvolvimento de procedimento analítico em fluxo com multicomutação para a determinação espectofotométrica de ácido úrico em urina". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-05102009-105307/.
Abstract (sommario):
A mecanização de procedimentos analíticos em análises clínicas traz vantagens tais como minimização de erros sistemáticos e do tempo das análises. Sistemas de análises em fluxo com multicomutação apresentam grandes potencialidades nesse sentido, atendendo às necessidades da mecanização de procedimentos analíticos de maneira versátil e robusta. Estes sistemas permitem minimizar o consumo de reagentes e a geração de resíduos, devido ao gerenciamento preciso de pequenos volumes de soluções por dispositivos controlados eletronicamente, tais como microbombas solenoide. O fluxo pulsado proporcionado pelas microbombas e a estratégia da amostragem binária melhoram a mistura entre amostra e reagentes. O ácido úrico é o principal produto final do metabolismo de purinas. A determinação deste analito em amostras de urina apresenta importância clínica, uma vez que sua concentração pode auxiliar no diagnóstico de disfunções no organismo humano, como a gota e o mau funcionamento dos rins. Um procedimento analítico empregando sistema de análises em fluxo com microbombas solenoide foi desenvolvido para a determinação de ácido úrico em amostras de urina. Os íons Cu(II) são reduzidos pelo ácido úrico a íons Cu(I), que podem ser quantificados por espectrofotometria na presença do ácido 4,4\'-dicarboxi-2,2\'- biquinolínico (BQA). Resposta linear foi observada entre 10 e 100 µmol L-1 de ácido úrico, sendo a curva analítica representada pela equação A=(0,0063±0,0002)CAU + (0,0285±0,0040), r = 0,999, em que CAU é a concentração de ácido úrico em µmol L-1. O limite de detecção foi estimado em 3,0 µmol L-1 (99,7% de nível de confiança; n = 20). O coeficiente de variação foi estimado em 1,2% com 20 medidas de uma solução de ácido úrico 75 µmol L-1 e a frequência de amostragem foi de 150 h-1. As principais espécies concomitantes presentes na urina não interferem na determinação de ácido úrico em concentrações até 5 vezes maiores que as usualmente encontradas. Recuperações entre 91 e 112% foram estimadas e os resultados das análises de 4 amostras de urina concordaram com os obtidos pelo procedimento enzimático para a determinação de ácido úrico (95% de nível de confiança). O alto grau de diluição da amostra necessário (100 vezes) minimiza o volume de amostra utilizado e os efeitos de matriz. Uma simples reconfiguração do sistema e a reotimização das frações volumétricas permitiram que a amostra fosse diluída em linha por reamostragem na zona dispersa. Resposta linear foi observada até 5,0 mmol L-1 de ácido úrico, sendo a curva analítica obtida representada pela equação A=(0,105±0,001) CAU + (0,023±0,003), r=0,999, em que CAU é a concentração de ácido úrico em mmol L-1. O coeficiente de variação, o limite de detecção e a frequência de amostragem foram estimados em 1,0%, 0,2 mmol L-1 e 95 h-1, respectivamente. Os resultados da análise de 3 amostras de urina concordaram com os obtidos pelo procedimento enzimático, com nível de confiança de 95%Mechanization of analytical procedures in clinical analysis brings advantages such as minimization of systematic errors and analysis time. Multicommuted flow systems attain the requirements to mechanization of analytical procedures in a versatile and robust way, minimizing reagent consumption and waste generation, due to the low solution volumes handled by electronically controlled devices, such as solenoid micro-pumps. The pulsed flow characteristic of the micro-pumps and the binary sampling approach improve sample and reagent mixing. Uric acid is the main end product of purine metabolism and its determination in urine shows clinical importance, because its concentration can be related to human organism dysfunctions, such as gout and renal disorders. An analytical procedure employing a flow system with solenoid micro-pumps was developed, aiming the determination of uric acid in urine samples. Cu(II) ions are reduced by uric acid to Cu(I) ions that can be quantified by spectrophotometry in the presence of 2,2´-biquinoline 4,4´-dicarboxylic acid (BCA). Linear analytical response was observed between 10 and 100 µmol L-1 uric acid and the analytical curve corresponds to the equation A=(0.0063±0.0002) CUA + (0.0285±0.0040), r = 0.999, in which CUA is the uric acid concentration in µmol L-1. The detection limit was estimated as 3.0 µmol L-1 (99.7% confidence level; n = 20). The coefficient of variation was estimated in 1.2% with 20 replicates of a 75 µmol L-1 uric acid solution and sampling rate of 150 h-1 was achieved. The main concomitant species does not interfere in uric acid determination in concentrations up to 5-fold higher than that usually found in urine samples. Recoveries from 91 to 112% were estimated and the results for 4 urine samples agreed with those obtained by the commercially available enzymatic kit for determination of uric acid (95% confidence level). The 100-fold sample dilution minimizes sample consumption and matrix effects. A simple system reconfiguration and a re-optimization of volumetric fractions attained on-line sample dilution by zone sampling. Linear response was observed up to 5.0 mmol L-1 uric acid and the analytical curve corresponds to the equation A=(0.105±0.001) CUA\' + (0.023±0.003), r = 0.999, in which CUA\' is the uric acid concentration in mmol L-1. The coefficient of variation, detection limit and sampling frequency were estimated as 1.0%, 0.2 mmol L-1 and 95 h-1, respectively. The results of the analysis of 3 urine samples also agreed with those obtained with the enzymatic procedure at the 95% confidence level
13
Hannon, Sarrah. "Analysis of cocaine adulterants and their metabolites in real patient urine samples". Thesis, Boston University, 2013. https://hdl.handle.net/2144/12114.
Abstract (sommario):
Thesis (M.S.)--Boston UniversityCocaine is one of the most common drugs of abuse in the United States today, but street-quality cocaine is decreasing in purity each year. This change in purity requires a shift in the focus of cocaine analysis in forensic laboratories. In recent years, many federal agencies have begun testing and profiling for the adulterants and diluents present in cocaine samples submitted as evidence. By analyzing the compounds present in the street-quality samples, forensic chemists may be able to track the cocaine back to its source, based on the unique identities of certain adulterants. Many of the adulterants currently being added to cocaine are dangerous on their own, even though they may enhance the effects of the cocaine. For this reason many doctors and forensic pathologists are interested in the identities of the adulterants present. Often times, a sample of the cocaine ingested may not be available for testing. Thus, there is a need for the development of methods to test for these adulterants and their metabolites in biological samples. The objective of this research is to develop extraction and instrumental analysis methods for several common cocaine adulterant metabolites, in an effort to create a geographical profile of human urine samples that tested positive for benzoylecgonine, a cocaine metabolite, and exploring the possible trends.
14
Kelly, Barbara M. "The analysis of biological fluids for acylcarnitines". Thesis, Open University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326566.
15
Dumitrescu, Vlad Andrei. "Comparative analysis of biogas slurry and urine as sustainable nutrient sources for hydroponic vertical farming". Thesis, Linköpings universitet, Tema vatten i natur och samhälle, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-96368.
Abstract (sommario):
Sustainable alternatives to using mined nutrients in agriculture must be found in order to limit environmental impacts such as eutrophication, habitat destruction and greenhouse gas emis-sions. Biogas slurry and urine recycled to hydroponic food production (a type of soilless agri-culture) have the potential of providing inorganic nitrogen and phosphorus, the main essential nutrients required for plant growth. A Life Cycle Inventory Assessment (LCI) methodology has been used to compare the systems of producing artificial fertilizer, biogas slurry and urine based nutrient solutions for the growth of Brassica rapa L. (Chinese cabbage) in the context of a large scale hydroponic vertical farm. Costs and energy requirements have been the basis of the comparison and results show that both biogas slurry and urine are considerably cheaper than the commercial alternative and based on the nutrient content they have the potential of being successful nutrient solutions after dilution and nutrient supplementation. Filtration might also be required in order to remove suspended particles and pathogens.
16
De, Kock Neil. "The development of direct infusion mass spectrometry method for analysis of small metabolites in urine". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80213.
Abstract (sommario):
Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: This study focused on the development of an analytical method whereby creatinine, creatine and caffeine could be determined quantitatively. Urine is the preferred body fluid for the analysis of metabolites that the body excretes after administration of medicinal and illicit drugs. The detection of these metabolites depends on the volume of water the patient has drunk or, in criminal cases, the amount of water the suspect may deliberately add to their urine to dilute it. Creatinine, whose concentration in urine has been found to correlate with muscle mass, is chosen as an endogenous control substance against which the metabolite concentration is compared. While high performance liquid chromatography with ultraviolet detection (HPLC–UV) is commonly selected for the analysis, the quality of chromatography is affected by the fact that creatinine, being highly polar, is not retained in the reversed-phase columns. Furthermore, urine contains many polar substances that elute with the solvent front along with creatinine, thereby grossly affecting HPLC measurements. Hydrophilic interaction chromatography (HILIC) is a good alternative, although these methods generally require extensive sample preparation. Direct infusion electrospray ionization mass spectrometry (DI–ESI–MS) is ideally suited to highly polar compounds and was selected for this work. Pneumatically assisted ESI is preferred above the standard ionization method of atmospheric pressure chemical ionization (APCI) since pneumatically assisted ESI disperses the solution into ion-containing aerosol droplets which do not promote online conversion of creatinine to creatine. The objective of this study was to develop a simple and sensitive DI–ESI–MS method for the determination of various compounds in urine with creatinine as analytical reference compound and internal standard (IS). The analytical method development includes addition of 1-methyl-3-phenylpropylamine as a primary IS to standard solutions as well as to urine samples, followed by direct infusion of the sample into a mass spectrometer to determine the absolute concentrations of creatinine, creatine and caffeine. After appropriate instrument conditions were established, linear graphs of analyte-IS signal intensity ratios were obtained. The ratio of the concentration of the analyte (drug or metabolite) to that of creatinine (as IS) may be used to determine analyte concentration in artificial samples and/or urine. This method is not affected by change in fluid volume or adulteration of urine samples because the analyte-to-creatinine ratio remains unchanged. As part of this study, the developed DI–ESI–MS method was compared with an LC–UV–MS method developed for this purpose.
AFRIKAANSE OPSOMMING: Hierdie studie fokus op die ontwikkeling van ‘n analitiese metode waardeur kreatinien, kreatien en kaffeïen kwantitatief bepaal kan word. Uriene is die voorkeur liggaamsvloeistof vir die analise van metaboliete wat deur die liggaam, na administrasie van mediese en onwettige middels, uitgeskei word. Die deteksie van hierdie metaboliete hang van die volume water af wat die pasiënt gedrink het, of in strafbare gevalle, die hoeveelheid water wat verdagtes met opset by hul uriene gevoeg het ten einde dit te verdun. Daar is bevind dat die konsentrasie van kreatinien in uriene met spiermassa korreleer, derhalwe is kreatinien as ‘n interne kontrolemiddel gekies waarmee die metaboliet-konsentrasie vergelyk kan word. Hoë-druk vloeistofchromatografie met ultravioletdeteksie (HPLC–UV) word algemeen vir die analise van kreatinien ingespan, maar die gehalte van die chromatografie word deur die hoogs polêre aard van kreatinien beïnvloed en het swak retensie in omgekeerde-fasekolomme tot gevolg. Bowendien, uriene bevat groot hoeveelhede polêre middels wat saam met kreatinien in die oplosmiddelfront elueer en sodoende HPLC-bepalings uitermatig beïnvloed. Hidrofiliese interaksiechromatografie (HILIC) is ‘n goeie alternatief, ofskoon omvangryke monster-voorbereidings algemeen vereis word. Direkte inspuitelektrosproei-ionisasiemassaspektrometrie (DI–ESI–MS) is ideaal geskik vir hoogs polêre stowwe en is vir hierdie studie gekies. Pneumatiese hulp-ESI word bo die standaard ionisasie-metode van lugdruk chemiese ionisasie (APCI) verkies weens pneumatiese hulp-ESI se vermoë om die oplosmiddel in aërosoldruppels wat ione bevat, te versprei – sonder die aanlynomskakeling van kreatinien na kreatien. Die doel van hierdie studie was om ‘n eenvoudige en sensitiewe DI–ESI–MS-metode te ontwikkel wat verskeie stowwe in uriene kan bepaal deur kreatinien as analitiese verwysingsmiddel en interne standaard (IS) vir die opstelling van ‘n IS-kalibrasiekurwe te gebruik. Die analitiese metode-ontwikkeling sluit die gebruik van 1-metiel-3-fenielpropielamien as primêre IS in. Die IS word tot standaard oplossings en urienemonsters gevoeg, gevolg deur direkte inspuiting van die monster in ‘n massaspektrometer om die absolute konsentrasies van kreatinien, kreatien en kaffeïen te bepaal. Lineêre kurwes van die seinintensiteitsverhouding van analiet tot IS is verkry na gepaste instrumentkondisies vasgestel is. Die verhouding van konsentrasie van die analiet (middel of metaboliet) tot dié van kreatinien (as IS) mag gebruik word om die analietkonsentrasie in die standaard oplossings en/of urienemonster te bepaal. Die metode word nie deur veranderinge in die vloeistofvolume of verwatering van urienemonsters beïnvloed nie, weens die analiet-tot-kreatinienverhouding wat onveranderd bly. ‘n LC–UV–MS-metode is voorts ontwikkel om die ontwikkelde DI–ESI–MS-metode se data te vergelyk.
17
Wu, Ruige, e 吴瑞阁. "Microchip-capillary electrophoresis with two-dimensional separation and isotachophoresis preconcentration for determining low abundanceproteins in human urine and dairy products". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46506044.
18
Shreeram, Devesh Dadhich. "Electrochemical Analysis of Genetically Engineered Bacterial Strains in a Urine-Based Microbial Fuel Cell". University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1458814734.
19
Low, Ann Stewart. "An evaluation of analytical procedures for detection of drug abuse with particular reference to opiates". Thesis, Robert Gordon University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242985.
20
Kim, Yuni T. "The effects of broccoli on the excretion of urinary conjugates". Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/38535.
Abstract (sommario):
The effects of dietary broccoli on the body's ability to detoxify were studied in 18 male subjects between the ages of 22-40 years. The biological parameters used for measuring detoxification were the four major urinary conjugates, namely, mercapturates, sulfoconjugates, glucuronides, and amino acid conjugates. Dietary broccoli increased the urinary excretion of mercapturates and sulfoconjugates, but did not influence the excretion of glucuronides and amino acid conjugates. A significant linear trend was observed over the six-day broccoli diet treatment for both urinary mercapturate (P<0.005) and sulfoconjugate (P<0.0001) excretion. The linear trend for the mercapturate excretion was in a dose-dependent manner, resulting in a 1.3 and 2.1 fold increase by the third and sixth days, respectively, of the broccoli diet, compared to the control. For sulfoconjugates, an unexpected decrease was observed on the first day of the broccoli diet. However, within the six-day broccoli dietary treatment, a continuous increase in conjugate excretion was observed, resulting in a 2.5 fold increase by the sixth day compared to the first day. The excretion of sulfoconjugates was not necessarily dose-dependent, and increased excretion at the highest level of broccoli (500 g) could be due to a time effect. Overall, sulfoconjugate excretion was the highest (3.98-8.91 mmole/24 h) followed by the amino acid conjugates (3.06-5.99 mmole/24 h) and glucuronides (2.85-3.54 mmole/24 h). Mercapturate excretion was the lowest (0.16-0.34 mmole/24 h). In spite of its low excretion level, the level of urinary mercapturates appeared to be the most responsive urinary conjugate to the different levels of broccoli diet.Ph. D.
21
Diaz, Sílvia de Oliveira. "Pregnancy and newborns disorders followed by urine metabolomics". Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13110.
Abstract (sommario):
Doutoramento em QuímicaChapter 1 introduces the scope of the work by identifying the clinically relevant prenatal disorders and presently available diagnostic methods. The methodology followed in this work is presented, along with a brief account of the principles of the analytical and statistical tools employed. A thorough description of the state of the art of metabolomics in prenatal research concludes the chapter, highlighting the merit of this novel strategy to identify robust disease biomarkers. The scarce use of maternal and newborn urine in previous reports enlightens the relevance of this work. Chapter 2 presents a description of all the experimental details involved in the work performed, comprising sampling, sample collection and preparation issues, data acquisition protocols and data analysis procedures. The proton Nuclear Magnetic Resonance (NMR) characterization of maternal urine composition in healthy pregnancies is presented in Chapter 3. The urinary metabolic profile characteristic of each pregnancy trimester was defined and a 21-metabolite signature found descriptive of the metabolic adaptations occurring throughout pregnancy. 8 metabolites were found, for the first time to our knowledge, to vary in connection to pregnancy, while known metabolic effects were confirmed. This chapter includes a study of the effects of non-fasting (used in this work) as a possible confounder. Chapter 4 describes the metabolomic study of 2nd trimester maternal urine for the diagnosis of fetal disorders and prediction of later-developing complications. This was achieved by applying a novel variable selection method developed in the context of this work. It was found that fetal malformations (FM) (and, specifically those of the central nervous system, CNS) and chromosomal disorders (CD) (and, specifically, trisomy 21, T21) are accompanied by changes in energy, amino acids, lipids and nucleotides metabolic pathways, with CD causing a further deregulation in sugars metabolism, urea cycle and/or creatinine biosynthesis. Multivariate analysis models´ validation revealed classification rates (CR) of 84% for FM (87%, CNS) and 85% for CD (94%, T21). For later-diagnosed preterm delivery (PTD), preeclampsia (PE) and intrauterine growth restriction (IUGR), it is found that urinary NMR profiles have early predictive value, with CRs ranging from 84% for PTD (11-20 gestational weeks, g.w., prior to diagnosis), 94% for PE (18-24 g.w. pre-diagnosis) and 94% for IUGR (2-22 g.w. pre-diagnosis). This chapter includes results obtained for an ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) study of pre-PTD samples and correlation with NMR data. One possible marker was detected, although its identification was not possible. Chapter 5 relates to the NMR metabolomic study of gestational diabetes mellitus (GDM), establishing a potentially predictive urinary metabolic profile for GDM, 2-21 g.w. prior to diagnosis (CR 83%). Furthermore, the NMR spectrum was shown to carry information on individual phenotypes, able to predict future insulin treatment requirement (CR 94%). Chapter 6 describes results that demonstrate the impact of delivery mode (CR 88%) and gender (CR 76%) on newborn urinary profile. It was also found that newborn prematurity, respiratory depression, large for gestational age growth and malformations induce relevant metabolic perturbations (CR 82-92%), as well as maternal conditions, namely GDM (CR 82%) and maternal psychiatric disorders (CR 91%). Finally, the main conclusions of this thesis are presented in Chapter 7, highlighting the value of maternal or newborn urine metabolomics for pregnancy monitoring and disease prediction, towards the development of new early and non-invasive diagnostic methods.
O Capítulo 1 descreve o enquadramento deste trabalho identificando as doenças pré-natais relevantes e os métodos de diagnóstico actualmente disponíveis. É depois apresentada a metodologia seguida, assim como uma breve introdução dos princípios dos métodos analíticos e estatísticos aplicados. O capítulo é concluído com uma descrição do estado da arte na área de metabolómica em investigação pré-natal, identificando o mérito desta inovadora estratégia para a identificação de marcadores robustos de doenças pré-natais. A relevância deste trabalho torna-se clara através do escasso uso de urina materna e do recém-nascido em trabalhos anteriores. O Capítulo 2 descreve os procedimentos experimentais utilizados neste trabalho, incluindo condições de amostragem, recolha e preparação das amostras, protocolos de aquisição e de tratamento dos dados. A caracterização da composição da urina materna, através de espectroscopia de Ressonância Magnética Nuclear (RMN) de protão é apresentada no Capítulo 3. Define-se o perfil metabólico urinário característico para cada trimestre de gravidez, tendo sido encontrado um conjunto de 21 metabolitos descritivo das alterações metabólicas ocorridas ao longo da gravidez. 8 metabolitos foram encontrados a variar com a gravidez, pela primeira vez, tendo sido confirmadas variações metabólicas conhecidas. É ainda estudado o efeito do não-jejum (usado neste trabalho) como possível factor de confusão. O Capítulo 4 apresenta o estudo metabolómico de urina materna do 2º trimestre para o diagnóstico de doenças fetais e previsão de complicações mais tarde desenvolvidas. Este estudo compreende a aplicação de um método de selecção de variáveis desenvolvido no âmbito desta tese. Observou-se que as malformações fetais (e, especificamente, do sistema nervoso central, SNC) e as cromossomopatias (e, especificamente, a trissomia 21, T21) são acompanhadas por alterações nos metabolismos energético, dos aminoácidos, lípidos e nucleótidos, enquanto que as cromossomopatias mostraram ser acompanhadas por uma desregulação adicional dos metabolismos dos açúcares, ciclo da ureia e/ou biossíntese da creatinina. A validação dos modelos multivariados revelou taxas de classificação (CR) de 84% para malformações (87%, SNC) e 85% para CD (94%, T21). Para o parto pré-termo, pré-eclampsia (PE) e restrição de crescimento intrauterino (RCIU) observaram-se perfis que podem ajudar à previsão precoce, com CR 84% para pretermo (11-20 semanas de gestação, g.w. pré-diagnóstico), 94% para PE (18-24 g.w. pré-diagnóstico) e 94% para RCIU (2-22 g.w. pré-diagnóstico). Este capítulo inclui resultados obtidos por cromatografia líquida de ultra eficiência acoplada a espectrometria de massa (UPLC-MS) para pré-pretermo e correlação com os dados de RMN. Um possível composto marcador foi detectado mas a sua identificação não foi possível. O Capítulo 5 descreve o estudo metabolómico por RMN da diabetes mellitus gestacional (DMG), estabelecendo-se um perfil metabólico potencialmente preditivo da doença (CR 83%, 2-21 g.w. pré-diagnóstico). Verificou-se ainda que o espectro de RMN contém informação sobre o fenótipo individual, capaz de prever a necessidade futura de tratamento com insulina (CR 94%). No Capítulo 6 demonstra-se o impacto do tipo de parto (CR 88%) e género do bebé (CR 76%) no perfil da urina do recém-nascido. Verificou-se ainda que a prematuridade, depressão respiratória, crescimento grande para a idade gestacional e malformações induzem perturbações metabólicas relevantes (CR 82-92%), assim como algumas doenças maternas como a DMG (CR 82%) e doenças psiquiátricas (91% CR). Finalmente, no Capítulo 7 apresentam-se as principais conclusões deste trabalho, enfatizando o potencial da metabolómica de urina materna e do bebé para o acompanhamento da gravidez e previsão de doenças, visando o desenvolvimento de novos métodos de diagnóstico precoce e não-invasivo.
22
Troster, Charles Micah Smolkin. "Trace analysis of cyclophosphamide and its metabolites in urine by liquid chromatography-tandem mass spectrometry". Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29263.
Abstract (sommario):
Cyclophosphamide (CP) is an antineoplastic drug used to treat a wide variety of cancers and immune disorders. CP is also a highly toxic alkylating agent, classified as an IARC Group 1 carcinogen. Workers in health-care environments are vulnerable to occupational exposure to CP, primarily via inhalation and dermal absorption. CP is a prodrug; both its therapeutic effectiveness and toxicity are activated through metabolism. To date, however, no study measuring occupational exposure to CP has successfully analyzed its metabolites. The main objective of this work was to develop an analytical method for CP, as well as its metabolites 4-ketocyclophosphamide (KCP) and carboxyphosphamide (CBP), in urine samples collected from health-care workers at risk of CP exposure.
A liquid chromatography-tandem mass spectrometry (LC/MS-MS) method was optimized for CP, KCP and CBP on two different instruments. Post-column infusion showed that the matrix effects resulting from synthetic urine could be separated from the analyte peaks by LC. Estimated instrument limits of quantitation for CP, KCP and CBP in neat solvent were respectively 4.2, 8.2 and 57 ng/L. These parameters were sufficient to meet a quantitation target of 50 ng/L CP in urine, but suggested a need to reduce sample volume to reach a 2.5 ng/L target for KCP and CBP.
Solid-phase extraction (SPE) was explored as a means to exchange the sample matrix for clean solvent and reduce sample volume. Previously developed SPE methods for CP were not designed to include the more polar metabolites, and thus required modification. The best retention of metabolites was seen on a C¹⁸ sorbent with reduced carbon loading. Retention was improved further under acidic loading conditions, but this had to be controlled carefully since CBP can decompose more rapidly at acidic pH. All three analytes were observed to elute with methanol.
23
Cromwell, Wyn Zhang. "An Analysis of the Loops of Henle and Urine Concentrating Mechanisms in the Kangaroo Rat". Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/144330.
24
Fong, Ka-wah Martin, e 方家華. "Adaptation of a simplified method for urinary iodine for studying the iodine status of local Chinese". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31971726.
25
Härmä, Johan. "Validation of a method for analyzing urinary Cystatin C and analysis of ULSAM-77 urine samples". Thesis, Uppsala universitet, Institutionen för medicinsk biokemi och mikrobiologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-177342.
Abstract (sommario):
Objective New biomarkers for acute kidney injury are needed and urinary Cystatin C is one alternative. The objective was to validate a urinary Cystatin C method on Mindray BS-380 comparing urine samples from the Uppsala Longitudinal Study of Adult Men (ULSAM-77) and urine samples from a reference group for Cystatin C. A visual control for a relationship between Cystatin C and C-reactive protein (CRP) and interleukin 6 (IL-6) respectively was made. Methods Precision, linearity, recovery, interference, and stability of the urine cystatin C method were investigated. Comparisons were made between ULSAM-77 samples and a reference group samples consisting of ordinary people. Results The highest total imprecision was 10.24 % for the sample with the lowest concentration. The second lowest concentration had 4.21 % total variation coefficient. The linearity equation was y = 0.99x – 0.01 with an R2-value of 0.99. The recovery for all concentrations was always 91 % or more. No interference from hemoglobin at a concentration of 10 g/L was found. The samples were stable at +5°C for seven days. The median for the samples from ULSAM-77 was 0.09 mg/L and the median for the reference samples was 0.06 mg/L. There was no obvious relationship between Cystatin C and CRP/IL-6 from ULSAM-77. Conclusion Reliable data of urinary Cystatin C can be analyzed on a Mindray BS-380. The level of urinary Cystatin C was higher for people age 77 than for those with a median age of 49. There was no correlation between the concentration of Cystatin C in urine and the levels of CRP and IL-6.
26
Bulusu, Sudha. "Analysis of organic acids by high performance liquid chromatography in urine and plasma and its applications". Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280405.
27
Li, Xin. "Comparative evaluation of the extraction and analysis of urinary phospholipids and lysophospholipids using MALDI-TOF/MS". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/265182.
Abstract (sommario):
京都大学新制・課程博士
博士(医学)
甲第23410号
医博第4755号
新制||医||1052(附属図書館)
京都大学大学院医学研究科医学専攻
(主査)教授 村川 泰裕, 教授 長尾 美紀, 教授 柳田 素子
学位規則第4条第1項該当
Doctor of Medical Science
Kyoto University
DFAM
28
Van, Buynder Paul G. "The epidemiology of renal disease in Aboriginal Australians". Thesis, The University of Sydney, 1991. https://hdl.handle.net/2123/26311.
Abstract (sommario):
Data from dialysis units in the Northern Territory and, from a rural community screening program in South Australia, suggested there was a high prevalence of renal disease in Aboriginal Australians. This thesis documents the high prevalence of urinary abnormalities in three Aboriginal communities in the Northern Territory and examines factors of aetiological relevance.
After ethical approval from the local institutional ethics committee which has Aboriginal
representation, a randomly chosen group of 327 adults and 180 children consented to participate in pilot studies in three communities. Subsequently a family-based study of 16 families comprising all 219 persons over the age of 10 years was undertaken in the community with the highest prevalence of renal disease.
Subjects with renal disease were identified on the basis of a urinary protein to creatinine ratio of > 50 mg/mmol; this measure was shown to be reproducible; urine was also examined by microscopy and culture. Anthropometric and blood pressure measurements were made under standard conditions. Biochemical parameters were assayed on a sample of blood collected 2 hours after a 75g glucose load (in adults) or at the time of collection of throat and skin swabs for streptococcal surveillance (in children).
In the community with the highest frequency of renal disease, some of the renal disease was not associated with diabetes, but was familial and associated with glomerular haematuria; in this same community glomerular haematuria and significant proteinuria were seen also in children. In all three communities, renal disease was associated with obesity, diabetes mellitus and hypertension. In none of the communities was renal disease associated with HBsAG, or evidence of hepatic disease. Although urinary tract infection was detected in some subjects with diabetes, it was not frequent enough to account for the high prevalence of renal disease in diabetics, nor for the high prevalence of renal disease in the Aboriginal communities studied.
29
Yap, Bin Kiat. "Exercise-stress responses of urinary hormones". Thesis, The University of Sydney, 1994. https://hdl.handle.net/2123/26858.
Abstract (sommario):
Knowledge on the effects of episodic or short-term exercise-stress on changes of corticosteroids, androgenic steroids and gonadotropins still remains fragmentary and inconclusive. In this study an alternative approach to investigate these changes, based on the concentration ratios of urinary total testosterone (T), luteinizing hormone (LH), free cortisol(F),cortisone (E) and their primary metabolites tetrahydrocortisol (THF) and tetrahydrocortisone (THE), was developed to profile shortterm exercise-stress responses in healthy, drug-free male athletes and sedentary subjects.
The hormonal concentrations were measured using the sensitive and accurate gas chromatography-mass selective detection (GC MSD) and microparticle enzyme immunoassay (MEIA) analytical techniques which were developed. Stress profiles derived from exercise-stress at V02max, 60-80% VOgmax and 50-55% VOzmax were plotted using the ratios of E/F, THE/F, THE/E, LH/T, LH/F, LH/E, T/F and T/E.
Significant changes between the basal and post-exercise ratios were found to be consistent and more representative of acute changes in stress levels compared to single corticosteroid and testosterone concentrations. Marked changes in LH values were also observed to reflect a dramatic increase in stress— response.
The ratio profiling method was also employed to investigate the urinary hormonal changes of a separate group of athletes who were subjected to mild exercise (50% VOZmax) combined with warm (27°C) and moderate humidity (64%). Variation in temperature and humidity resulted in changes to some of the corticosteroid ratio profiles which were consistent with those found in the earlier trials. In a subsequent field study the swim-stress responses of a group of teenage, male swimmers participating in a typical training session during a competition season were also profiled. Whilst no marked changes were found in the LH and T ratios, some of the corticosteroid ratios showed a trend towards positive significance. The profiles appeared to reflect the level of swim-stress prescribed in the training that was less than an equivalent of treadmill running at 60-80% VOZmax The consistent results obtained from the evaluation of the stress-response profiles showed that the profiling approach based on the proportionate changes of urinary F,E,THF,THE,T and LH levels could be utilised as a reliable method for evaluating the inter-relationship between the various hormones in human stress studies. The method could be of advantage in determining the training status of athletes in competitions and for drug-testing purposes.
30
Silva, Júnior Jarbas Miguel da. "Excreção urinária de derivados de purinas e de compostos nitrogenados de zebuínos em pastejo". Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/5825.
Abstract (sommario):
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This study aimed evaluating the excretion of purine derivatives and nitrogen compounds in zebu cattle grazing, on different days and times within days. The experiment was conducted in the cattle department of the Federal University of Viçosa / MG, using five Nelore heifers with an average body weight of 300 ± 15 kg and 20 months of age, in 5x5 Latin square design. The experimental treatments were defined to represent those commonly used in the dry season, as follows: control (mineral salt), concentrated with 20.31% crude protein (CP) on dry matter (DM) being offered (OF) level of 0.5 to 1% of body weight fasted (BWF) OF5 and OF10, respectively; and two concentrated self- regulating (SR) consumption, containing 69.38% CP on a DM basis (20% urea and 20% salt) offered ad libitun (SR70) and other concentrate containing 39.73% CP based on MS being offered ad libitum (SR40). The experimental periods was 18 days, with one day to perform 14 hours of fasting for weighing and adjustment of the quantities supplied, 12 days for adaptation to the experimental diets and five for total collection of urine and stool sample at the times of 0h00a.m. to 4h00a.m, 4h00a.m. to 8:00a.m., 8:00a.m. to 12:00p.m., 12:00p.m. to 4:00p.m., 4:00p.m. to 8:00p.m. and 20:00p.m. to 0:00a.m. For total collection of urine was used probe Folley number 26, coupled to polyethylene hose leading to a urine collection bag for urine closed system, which was emptied every two hours in the range of 8:00a.m. to 8:00p.m., and every four hours in the range from 8:00p.m. to 8:00a.m. and subsequently homogenized and cooled. The collected urine sampling was performed every four hours, measuring the volume, and withdrawing one sample were diluted in H 2 SO 4 at 0,036N and another don't diluted. To estimate fecal output, used the titanium dioxide, provided the total daily amount of 15g, between 9 th and 18 th day of each period. To estimate the intake of pasture, used the indigestible neutral detergent fiber (iNDF) as internal indicator. Was performed by collecting pasture technique for determining the square potentially digestible dry matter (PDDM) on the third day of each experimental period, and on days 14 th and 18 th was held grazing simulation to estimate the consumption of constituents of diets. In urine samples the concentrations of creatinine, total nitrogen, urea, uric acid and allantoin. For statistical analysis we used the statistical program SAS Proc Mixed. Dry matter intake 10was higher (P<0.05) for the treatment OF10 compared to SR70, SR40 and control treatments but was not different (P>0.05) treatment OF5. The CP intake increased by supplementation (P<0.05), which caused no effect on DM intake from pasture. Excretions of creatinine did not change treatment, day and sampling period (P>0.05) and had a mean of 23.03 ± 0.30 mg / kgPC. Urinary relations of allantoin (Al) and uric acid (UA) with creatinine were not affected (P>0.05) by treatments, collection days and times of collection. The total nitrogen relations:creatinine and urea nitrogen:creatinine in urine showed interaction (P<0.05) between treatment and sampling period. The relationship between urea nitrogen:total nitrogen was influenced (P<0.05) only at time of collection. The nitrogen balance (NB) in g/day did not differ between treatments OF10, SR70 and SR40, however these had higher retention of N (P<0.05) than treatments OF5 and control, which were not different. The NB, in g/ging, showed differences (P<0.05) between treatments with concentrated, which did not differ (P> 0.05), and control treatment, with the lowest NB. The production of microbial N was not affected (P>0.05) by treatments. The microbial efficiency gPBmic/kgMOD and gPBmic/kgNDT was affected (P<0.05) by supplementation, being higher (P<0.05) for OF5, OF10 and SR70 treatments, which did not differ. The control and OF5, treatments had the lowest values were similar. The lack of effect of day and the collection period on allantoin and uric acid compared with creatinine has wide practical application, enabling use spot urine sample to calculate the excretion of purine derivatives at any time of day or night, and consequently the microbial production. Depending on the variations observed for total nitrogen and urea nitrogen relations with creatinine over 24 hours is not recommended the use of a single spot urine sample for determination of these nitrogen compounds.
O presente trabalho foi desenvolvido com os objetivos de avaliar a excreção dos derivados de purinas e de compostos nitrogenados em zebuínos em pastejo, em diferentes dias e períodos dentro de dias. O experimento foi conduzido no setor de gado de corte da Universidade Federal de Viçosa/MG, utilizando-se cinco novilhas Nelore com peso corporal médio de 300 ± 15kg e 20 meses de idade, distribuídas em quadrado latino 5x5. Os tratamentos experimentais foram definidos para representar aqueles normalmente utilizados na época seca do ano, sendo eles: controle (sal mineral), concentrado com 20,31% de proteína bruta (PB) com base na matéria seca (MS) sendo oferecido (OF) em nível de 0,5 e 1% do peso corporal em jejum (PCJ), OF5 e OF10, respectivamente; e dois concentrados autorreguladores (AR) de consumo, um contendo 69,38% PB com base na MS (20% de ureia e 20% de sal) ofertado ad libitun (AR70) e outro concentrado contendo 39,73% PB com base na MS sendo ofertado ad libitum (AR40). Os períodos experimentais possuíram 18 dias, sendo o dia um para realização de jejum de 14 horas para pesagem e ajuste das quantidades fornecidas, 12 para adaptação dos animais às dietas experimentais e cinco para a coleta total de urina e amostral de fezes, nos horários das 0h00 às 4h00, 4h00 às 8h00, 8h00 às 12h00, 12h00 às 16h00, 16h00 às 20h00 e 20h00 às 24h00. Para a coleta total de urina utilizou-se sonda de Folley no26, acoplada a mangueira de polietileno que conduziu a urina até uma bolsa coletora de urina por sistema fechado, que foi esvaziada a cada duas horas no intervalo das 8h00 às 20h00, e a cada quatro horas no intervalo das 20h00 às 8h00, sendo posteriormente homogeneizadas e resfriadas. A amostragem da urina coletada foi realizada a cada 4 horas, medindo-se o volume e retirando-se duas amostras, uma diluída com solução H2SO4 0,036N e não diluida. Para determinação da excreção fecal, utilizou-se o dioxido de titânio, fornecido na quantidade total diária de 15g, entre os dias 9 e 18 de cada período. Para estimativa do consumo de pasto, utilizou-se a fibra indigestível em detergente neutro (FDNi), como indicador interno. Realizou-se coleta de pasto pela técnica do quadrado para determinação da matéria seca potencialmente digestível (MSpd) no terceiro dia de cada período experimental, e nos dias 14o e 18o realizou-se simulação de pastejo para estimar os consumos dos constituintes das dietas. Nas amostras de urina foram determinadas as concentrações de creatinina, nitrogênio total, ureia, acido úrico e alantoína. Para análise estatística utilizou-se o programa estatístico Proc Mixed do SAS. O consumo de MS foi superior (P<0,05) para o tratamento OF10 em relação aos tratamentos AR70, AR40 e controle, mas não diferiu (P>0,05) do tratamento OF5. O consumo de PB aumentou com a suplementação (P<0,05), que não causou efeito sobre o consumo de MS do pasto. As excreções de creatinina não sofreram efeito de tratamento, dia e período de coleta (P>0,05) e apresentaram média de 23,03 ± 0,30 mg/kgPC. As relações urinárias da alantoína (Al) e do ácido úrico (AU) com a creatinina não foram influenciadas (P>0,05) pelos tratamentos, dias de coleta e horários de coleta. As relações nitrogênio total:creatinina e nitrogênio ureico:creatinina na urina apresentaram interação (P<0,05) entre tratamento e período de coleta. A relação entre nitrogênio ureico:nitrogênio total foi influenciada (P<0,05) apenas pelo horário de coleta. O balanço de compostos nitrogenados (BN), em g/dia, não diferiu entre os tratamentos OF10, AR70 e AR40, contudo esses apresentaram maiores retenções de N (P<0,05) que os tratamentos OF5 e controle, que não foram diferentes. O BN, em g/ging, apresentou diferença (P<0,05) entre os tratamentos com concentrado, que não diferiram entre si (P>0,05), e tratamento controle, que apresentou o menor BN. A produção de compostos nitrogenados microbianos não foi alterada (P>0,05) pelos tratamentos. A eficiência microbiana, em gPBmic/kgMOD e gPBmic/kgNDT foi afetada (P<0,05) pela suplementação, sendo maior (P<0,05) para os tratamentos OF5, OF10 e AR70, que não diferiram entre si. Os tratamentos controle e OF5, apresentaram os menores valores e foram semelhantes entre si. A ausência de efeito de dia e do período de coleta sobre a relação alantoína e ácido úrico com a creatinina tem grande aplicação prática, possibilitando utilizar a amostra spot de urina para calcular a excreção de derivados de purinas em qualquer horário do dia ou da noite, e consequentemente a produção microbiana. Em função das variações observadas para as relações nitrogênio ureico e nitrogênio total com a creatinina ao longo do período de 24 horas não se recomenda o uso de uma única amostra spot de urina para determinação destes compostos nitrogenados.
31
Li, Jiufeng. "Determination and evaluation of endocrine disrupting chemicals in urine samples of pregnant women by liquid chromatography-tandem mass spectrometry". HKBU Institutional Repository, 2020. https://repository.hkbu.edu.hk/etd_oa/757.
Abstract (sommario):
Endocrine disrupting chemicals (EDCs) are emerging contaminants that can interfere with the hormone system and may cause cancers, birth defects and reproductive system disorders. Prevalence of endocrine-related dysfunction and disease has increased steadily over the past decades. Although accumulating data suggest that these diseases have fetal origins, associations of EDC exposure during pregnancy and adverse health effects on both mothers and fetuses have not been thoroughly evaluated, particularly at multiple points in time. We firstly developed an analytical method for quantification of 28 EDCs (9 phthalates, 8 bisphenols, 5 parabens, 5 benzophenones and triclosan) in urine samples using ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometer. The method was applied to measure targeted compounds in a total of 5220 urine samples collected from 951 pregnant women at three trimesters and 1501 pregnant women at one or two trimesters in Wuhan, China between 2014 and 2015. Based on the quantification results, exposure patterns and health risks of 28 EDCs on participants were evaluated and discussed in detail below. Among these samples, bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), 4-hydroxybenzophenone (4-OH-BP), 2,4-dihydroxybenzophenone (BP-1), 2-hydroxy-4-methoxybenzophenone (BP-3), triclosan, mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono(2-ethylhexyl) phthalate (MEHHP), monobenzyl phthalate (MBzP), mono-n-butyl phthalate (MnBP), monoisobutyl phthalate (MiBP) were determined with detection rates exceeding 50%, in which BPA, BP-3, MeP and MnBP were the predominant compounds. We found the U-shaped trends of urinary concentrations of phthalate metabolites over trimesters. Parabens, benzophenones and triclosan displayed a downward trend over three visits. We also found the levels of targeted compounds varied by exposure-related factors, such as sampling seasons, physical activities, computer using time and decoration information. In addition, multiple EDCs were mostly determined at low doses over trimesters, indicating that real-world exposure of pollutants were dominated by low-dose mixtures. We then evaluated the combined health hazards induced by EDC exposure via calculating the estimated daily intakes on the basis of average urinary concentrations at three trimesters. It was found that 24.9% of participants had potential health risks caused by exposure to phthalate mixtures. The most frequency of cumulative risks occurred in women who were exposed to a high dose of one specific phthalate, di-n-butyl phthalate (DnBP) or di(2-ethylhexyl) phthalate (DEHP). We also evaluated the cumulative health risks of BPA and its alternatives and found that about 1.6% of participants were at risks induced by bisphenol exposure. Combined health hazards were mainly driven by one specific bisphenol (BPS or BPA). Our findings suggested that regional interventions of DnBP, DEHP, BPA and BPS in application and production should be tighten and/or taken. Considering the low-dose effects of BPA, we further investigated the associations of BPA and three major natural estrogens, including estrone (E1), estradiol (E2) and estriol (E3), at three trimesters of pregnancy. We observed non-monotonic dose-response relationships of BPA to E1, E2 and E3 over trimesters even when BPA concentrations were below the current safety thresholds. In the gender-stratified models, we found significant negative relationships (β < 0, p < 0.05) between BPA and E2 among mothers with male fetuses in the first trimester. However, we found that no significant relationship between BPA and E2 among mothers with female fetuses over three trimesters. Significant non-monotonic associations (from significant negative to positive associations) between BPA and E3 were observed among mothers with female fetuses in the second trimester. The above mentioned findings suggested the gender-specific and trimester-specific effects of BPA on estrogens. Our findings also indicated that the current tolerance daily intake value maybe not safe enough to evaluate the potential health risks induced by BPA exposure. We next investigated the effects of maternal exposure to phthalates on both mothers and fetuses. Associations of phthalate exposure with the risks of gestational diabetes mellitus (GDM) and plasma glucose levels were evaluated based on a nested case-control study design. It was found that the levels of phthalate metabolites in women with GDM were significantly higher than those without GDM. Meanwhile, positive associations between urinary concentrations of phthalate metabolites and the risks of GDM were obvious, indicating that phthalate exposure may be a risk factor for GDM. In addition, phthalate levels were related to the increased plasma glucose levels after 75 g oral glucose tolerance test. Our findings suggested that phthalates might disturb the glucose homeostasis and increase GDM risks. Furthermore, we assessed the trimester-specific and gender-specific effects of DEHP exposure on fetal growth, birth size and postnatal growth at 6, 12 and 24 months. We found that among male offspring, 1st-trimester DEHP was negatively related to fetal growth (β < 0, p < 0.05), but positively related to 24-month body mass index (BMI). 2nd-trimester DEHP was negatively related to fetal growth, birth weight and birth length, but positively related to the weight gain rates from birth to 12 months old. 3rd-trimester DEHP was positively (β > 0, p < 0.05) associated with birth weight, BMI at 6 and 12 months. However, among females, 1st-trimester DEHP was associated with increased birth length, while 2nd-trimester DEHP was negatively associated with BMI at 6 and 12 months. A negative association between DEHP and weight gain rates at 6 months was noted among females. Our findings indicated the second trimester maybe the sensitive window of DEHP exposure for offspring growth since 2nd-trimester DEHP levels were related to the decreased fetal growth, decreased birth size, but increased weight gain rates in early childhood age among male offspring. To investigate the mechanism underlying the associations of DEHP exposure with glucose and lipid metabolism, we investigated the biotransformation of DEHP and the disturbed metabolisms induced by MEHP, the putative toxic metabolite of DEHP, in human normal liver cell L02 using metabolomics and lipidomics. We found that MEHP was the major metabolite of DEHP. Decreased uptake of glucose and accumulation of glucose in liver cells were obvious after MEHP exposure. Phospholipid remodeling, incomplete fatty acid β-oxidation, inhibition of purine metabolism and glycolysis, and increased oxidative stress were noted in MEHP-exposed L02 cells, which were related to insulin resistance. In this work, we measured 28 EDCs in a total of 5220 urine samples provided by 951 pregnant women (three trimesters) and 1501 pregnant women (one or two trimesters) and then evaluated the exposure levels, exposure patterns (variations, variability and correlations), health risks and health effects of these compounds on pregnant women and fetuses. Our data suggested that participants had potential health risks induced by exposure to phthalates or bisphenols. Phthalate exposure was related with the increased plasma glucose levels and risks of GDM. Prenatal DEHP exposure may induce the intrauterine growth restriction and catch-up growth among males, which supported the evidence of fetal origin. To explore the underlying mechanisms of MEHP on glucose and lipid metabolic disorders, we exposed the human normal hepatic L02 cells with MEHP, and applied metabolomic and lipidomic approaches for finding potential biomarkers and disturbed pathways. We found that MEHP exposure inhibited glucose uptake, caused phospholipid remodeling and increased oxidative stress in L02. These findings suggest that the usage of products containing EDCs, particularly phthalates, in pregnant women should be limited in China, intervention of BPS should be considered, and threshold values of BPA are called for reevaluation.
32
Wiens, Kristy. "Design of an optical uroflowmeter and assessing bladder pressure through video analysis of the male urine stream". Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43722.
Abstract (sommario):
Voiding dysfunction, such as benign prostatic hyperplasia and impaired detrusor contractility, affects more than half of men over the age of 50. Uroflowmetry provides quantitative information of flow dysfunction by measuring the flow rate and total volume of urine expelled by the body. The majority of existing clinical uroflowmeters determine flow rate using a scale to measure increasing mass of urine expelled with time; however, they are expensive and typically found only in specialists’ offices, making it difficult for patients to receive testing. An opportunity therefore exists to develop a much more affordable device which would allow flow rate testing to become a part of routine care and to be conducted in a wider variety of environments such as General Practitioners’ offices and home monitoring. The high demand for digital cameras, particularly due to their extensive use in mobile devices, has resulted in their accelerated advancement and cost reduction. Therefore, a device based on this technology is investigated.
In addition to the development of this device, a study was conducted to investigate if information regarding bladder pressure may be obtained by analyzing digital images of the urine stream. Voiding dysfunction may result in abnormally high bladder pressure, caused by urinary obstruction, or low bladder pressure which may be caused by reduced detrusor contractility. The clinical implications and treatment for these two cases are very different; however, they present with similar low flow rate voiding patterns and cannot currently be distinguished non-invasively. It was postulated that increased inertia and turbulence may exist in high pressure flows, and may be identifiable in the digital images of the urine stream.
33
Buist, Neil R. M. "Fifty years in inborn errors of metabolism : from urine ferric chloride to mass spectrometry and gene analysis". Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/12724.
Abstract (sommario):
Prefatory material introducing a collection of articles spanning fifty years of research into inborn errors of metabolism. Table of Contents: 1. Introduction -- 2. Background information about inborn errors of metabolism -- 3. Lessons from phenylketonuria [PKU] -- 4. My role in developing new medical foods -- 5. My role in solving an epidemic of benzyl alcohol poisoning in premature infants -- 6. My role in galactosaemia research -- 7. My start in the metabolic world - screening tests in urine -- 8. My experiences in disaster relief -- 9. My first appearance in the medical literature -- 10. A selection of rare and unusual diseases -- 11. Tyrosinaemia type II; tyrosine aminotransferase deficiency -- 12. Iminodipeptiduria due to prolidase deficiency -- 13. Citrullinaemia -- 14. Rippling muscle disease -- 15. A fatal X-linked disorder of diarrhoea, diabetes mellitus and immune dysregulation -- 16. Infantile Refsum disease -- 17. Hereditary hypocalcuric hypercalcaemia -- 18. Carbohydrate deficient glycoprotein disease type IAPKU -- 19. Thiamine-responsive diabetes and deafness -- 20. Folinic acid-responsive seizures: a false alarm -- 21. S-adenosylmethionine hydrolase deficiency -- 22. Deficiency of complex III of the respiratory chain -- 23. Current research: quantitation of infant sucking behaviour -- 24. Discussion and summary.
34
Avery, Thomas W. "Further characterization of the direct injection nebulizer for flow injection analysis and liquid chromatography with inductively coupled plasma spectrometric detection". Virtual Press, 1988. http://liblink.bsu.edu/uhtbin/catkey/539620.
Abstract (sommario):
A direct injection nebulizer (DIN) was constructed in our laboratory and was evaluated as an interface between a liquid chromatography column and an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Optimum operating conditions, detection limits and reproducibility of the DIN closely matched literature data for a somewhat different commercial device. In addition, when using the DIN for sample introduction, the ICP detection exhibited uniform response towards phosphorous compounds of different volatilities.Department of Chemistry
35
Lugogo, Rita de Nicolo. "Quantitative assessment of daily urinary conjugates in an adult male population". Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-171211/.
36
Bordin, Keliani. "Avaliação de biomarcadores da exposição humana à fumonisina B1 nos alimentos em municípios dos estados de São Paulo e Santa Catarina, Brasil". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-23042015-140349/.
Abstract (sommario):
A fumonisina B1 (FB1) e uma micotoxina produzida pelo metabolismo secundário de espécies de Fusarium, principalmente F. verticillioides e F. proliferatum, os quais contaminam diversos alimentos antes e apos o processamento, sobretudo o milho e derivados, gerando graves problemas para a Saúde Pública e a qualidade dos alimentos. O objetivo deste trabalho foi avaliar a exposição humana a FB1 presente nos alimentos através da estimativa de ingestão da toxina na dieta e da análise de diferentes biomarcadores presentes em amostras de sangue, urina e cabelo. Além disso, foram investigados os efeitos da toxina através da avaliação de ácido fólico presentes em alimentos e em soro, e os níveis de uréia e creatinina presentes em soro. O estudo foi realizado em dois municípios dos Estados de São Paulo e Santa Catarina, cujos respectivos voluntários foram categorizados como de baixo consumo de derivados de milho (Grupo A, voluntários de Pirassununga/SP) e de alto consumo de derivados de milho (Grupo B, voluntários de Erval Velho/SC). As amostras de alimentos do Grupo A (Pirassununga/SP) foram fornecidas pelos voluntários (n=100) nos meses de Junho/2011, Setembro/2011, Dezembro/2011 e Marco/2012. Os voluntários do Grupo B (Erval Velho/SC) (n=20) forneceram amostras de alimentos no mês de Abril/2012. Em cada grupo, uma lista com 20 alimentos a base de milho foi entregue aos voluntários, para fornecimento de amostras daqueles disponíveis em suas respectivas residências em cada mês de amostragem, totalizando 122 amostras de derivados de milho no Grupo A e 17 amostras no Grupo B coletadas durante o estudo. Adicionalmente, aplicou-se um Questionário de Frequência Alimentar (QFA) e um Inquérito Recordatório de 24 horas (QIR - 24 h) no momento das coletas de amostras. Em cada mês de amostragem de alimentos, foram coletadas amostras de sangue, urina (somente Grupo A) e cabelo dos voluntários, sendo as amostras armazenadas a -20ºC (urina e cabelo) ou -80ºC (sangue) até o momento das análises. As amostras de alimentos foram submetidas a análise de FB1, sendo que as de farinha de milho foram também analisadas quanto ao teor de ácido fólico. Ambas as análises foram feitas através de cromatografia líquida de alta eficiência (CLAE). Em soro, foram avaliadas a relação esfinganina/esfingosina (Sa/So), resíduos de FB1, ácido fólico, uréia e creatinina. Em urina, foram analisados os níveis de FB1, creatinina para correção do volume urinário e a relação Sa/So. Em cabelo, foram analisados os resíduos de FB1 através de CLAE acoplada a espectrometria de massas. Todos os métodos de análise foram submetidos a procedimento de otimização e validação intra--laboratorial. A incidência de FB1 nos alimentos foi, em média, 72% (n=122) nas amostras do Grupo A (Pirassununga/SP) e 35% (n=17) no Grupo B (Erval Velho/SC). Os maiores níveis foram encontrados em amostras de pipoca provenientes do Grupo B, com uma amostra excedendo o limite de tolerância estabelecido no Brasil (2,500 µg kg-1). A ingestão diária provável média (IDPM) de FB1 no Grupo A foi de 63,3 ng kg-1 peso corpóreo (p.c.) dia-1, que corresponde a 3,1% da ingestão provisória máxima tolerável (IPMT) recomendada para fumonisinas (2.000 ng kg-1 p.c. dia-1). A IDPM do Grupo B apresentou uma média de 190,1 ng kg-1 p.c. dia-1 o que corresponde a 9,5% da IDMT. As concentrações de ácido fólico nas amostras de farinha de milho variaram de < 0,3 µg kg-1 (limite de quantificação do método) a 1.705 µg kg-1, com média de 713 ± 435 µg kg-1. Somente uma amostra apresentou nível de ácido fólico acima do valor mínimo estabelecido pela ANVISA. Em urina, a incidência de FB1 foi de 33,4% (n=251), com níveis médios de 3,19 ± 3,15 ng mg-1 de creatinina. Não houve correlação (P>0,05) entre as concentrações de FB1 na urina e nos alimentos. Os níveis de esfinganina foram mais elevados em mulheres, com 25,0% (n=116) de amostras positivas, em comparação à urina de homens, 10,4% (n=96). A relação Sa/So apresentou em média 0,91, 0,77 e 0,89 para urina de mulheres, homens e em combinação, respectivamente. Em soro, os níveis de esfingosina foram em média 2,48 ng mL-1 para o Grupo A e 5,01 ng mL-1 para o Grupo B. A relação Sa/So variou de 0,06 a 3,19 com média de 0,79 para o Grupo A e 0,78 para o Grupo B. Embora tenha havido correlação positiva (r=0,574, P<0,05) entre a relação Sa/So no soro e os dados de consumo de milho e derivados obtidos no QIR-24 h, não foram observadas correlações (P>0,05) entre a ingestão de FB1 e a relação Sa/So na urina ou soro. A concentração de ácido fólico no soro variou de 6,7 a 24,0 ng mL-1 (média de 13,4 ± 5,4 ng mL-1), com ambos os grupos (A e B) apresentando resultados dentro dos valores de referências. Não foram observados níveis detectáveis de FB1 nas amostras de soro. No entanto, FB1 foi detectada em 4 amostras de cabelo humano (7,2%) dos Grupos A e B, cuja concentração média foi de 21,3 ± 12,1 ng g-1. Em síntese, os resultados obtidos nas análises de biomarcadores de FB1 no presente trabalho estão de acordo com os valores de IDPM encontrados, indicando que a exposição a FB1 nas populações estudadas não representa um risco a saúde.Fumonisin B1 (FB1) is a mycotoxin produced by the secondary metabolism of Fusarium species, mainly F. verticillioides and F. proliferatum, which contaminates foods before and after processing and causes serious problems to public health and food quality. The aim of this study was to evaluate the human exposure to FB1 in food by means of estimated intake of toxin in the diet, and analysis of different biomarkers in serum, urine and hair. In addition, folic acid in food and blood as well urea and creatinin in serum were investigated to evaluate the toxin effects. The study was conducted in two cities of Sao Paulo and Santa Catarina States, where the respective volunteers were categorized as low-consumers of corn products (Group A, volunteers from Pirassununga/SP) and high-consumers of corn products (Group B, volunteers from Erval Velho/SC). Food samples from Group A (Pirassununga/SP) were provided by volunteers (n=100) in June/2011, September/2011, December/2011 and March/2012. The volunteers from Group B (Erval Velho/SC) (n=20) provided food samples in April/2012. In each group, a list of 20 corn products was given to volunteers, to allow them to check and collect the food items available in their homes at each sampling time. The total number of samples of corn products provided by the volunteers were 122 and 17 in Group A and Group B, respectively. Addicionally, a Food Frequency Questionnaire (FFQ) and a 24-Hours Dietary Recall Questionnaire (24h-DRQ) were applied by the time of sample collections. In each month of food samples collection, samples of blood, urine (only Group A) and hair from the volunteers were collected and storage at -20ºC (urine and hair) or -80ºC (blood) until analysis. Food samples were submitted to determination of FB1, and corn meal samples were also evaluated for folic acid levels. Both analysis were performed by high performance liquid chromatography (HPLC). In serum, analyses included sphinganine/sphingosine ratio (Sa/So), FB1 residue, folic acid, urea and creatinine. In urine, the levels of FB1, creatinine to correct urinary volume and Sa/So ratio were evaluated. In hair, FB1 residues were analysed by HPLC coupled to mass spectrometry. All the analytical methods were submitted to optimization and intra-laboratorial validation procedures. The mean incidences of FB1 in corn products were 72% (n=122) in samples of Group A (Pirassununga/SP), and 35% (n=17) of Group B (Erval Velho/SC). The higher levels were found in popcorn from Group B, with one sample exceeding the tolerance limit established in Brazil (2,500 µg kg-1). The mean probable daily intake (PDIM) of FB1 in Group A was 63.3 ng kg-1 body weigh (b.w.) day-1, which corresponds to 3.1% of provisional maximum tolerable intake (PMTDI) recommended for fumonisins (2,000 ng kg-1 b.w. day-1). PDIM of Group B was 190.1 ng kg-1 b.w. day-1, which represents 9.5% of PMTDI. Folic acid levels in corn meal ranged from < 0,3 µg kg-1 (quantification limit) to 1.705 µg kg-1, with a mean of 713 ± 435 µg kg-1. Only one sample had levels of folic acid above the minimum established by ANVISA. In urine, the incidence of FB1 was 33,4% (n=251), at mean levels of 3,19 ± 3,15 ng mg-1 of creatinine. There wasn\'t correlation (P>0.05) between concentrations of FB1 in urine and foods. Sphinganine levels were higher in woman, with 25.0% (n=116) of positive samples in comparison to urine of men, 10.4% (n=96). The mean Sa/So ratios were 0.91, 0.77 and 0.89 for urine of women, men and in combination, respectively. In serum, sphingosine presented a mean of 2.48 ng mL-1 to Group A and 5.01 ng mL-1 to Group B. Sa/So ratio ranged from 0.06 to 3.19 with a mean of 0.79 to Group A and 0.78 to Group B. Although a positive correlation (r=0.574, P<0.05) was found between Sa/So ratio in serum and corn consumption data obtained by 24h-DRQ, no correlation was observed (P>0,05) with FB1 intake and Sa/So ratio in urine or serum. Folic acid concentration in serum ranged from 6.7 to 24.0 ng mL-1 (mean of 13.4 ± 5.4 ng mL-1), with both groups (A and B) presenting levels within the reference valuies. There were no detectable levels of FB1 in serum samples. However, FB1 was detected in 4 human hair samples (7.2%) of Groups A and B, at a mean concentration was 21.3 ± 12.1 ng g-1. In summary, the results obtained in the analyses of FB1 biomarkers in the present study are in agreement with the PDIM values found, hence indicating that FB1 exposure in the populations studied do not represent a health concern.
37
McBride, M. B. "The development and evaluation of an HPLC method of analysis for nicotine and its major metabolites in urine". Thesis, University of Bristol, 1988. http://hdl.handle.net/1983/9268fc8e-2d95-426e-b6a3-7cdfd849fc15.
Abstract (sommario):
This dissertation details the development and evaluation of an HPLC method of analysis for nicotine and the metabolites cotinine, nicotine-1'-N-oxide and 3' hydroxycotinine in urine samples. The significance of nicotine, its absorption, metabolism and excretion in man and other animals have been described in Chapter 1. Chapter 2 deals with the development of the HPLC method of analysis using both isocratic and gradient elution with W detection. A selection of packing materials/mobile phases covering different retention mechanisms was investigated. A separation of nicotine, cotinine, nicotine- 1'-N-oxide and 3' hydroxycotinine and two chromatographic standards, N' acetyl nornicotine and 2-methyl-6-(3-pyridyl)- tetrahydro-(1,2)-oxazine was achieved on a Resolve C18 5μ radially packed cartridge using gradient elution under reverse phase partition conditions. N' acetyl nornicotine was later discarded in favour of 2-methyl-6-(3-pyridyl)-tetrahydro-(1,2)-oxazine which could be used as an internal standard. The statistical analysis of the instrument response to nicotine and its metabolites in standard solutions was examined in Chapter 3- A comparison of the measurement parameters peak height and peak area was made. Within-run and between-run precision were calculated. Calibration curves were constructed with Working-Hotelling 95% confidence bands and 95% confidence bounds for 90% of future observations. The limit of detection values were also statistically calculated. Precision was found to be low for some of the components and this was reflected in unacceptably high values of the limit of detection. The clean-up of urine samples and the extraction of the components of interest were investigated in Chapter 4. Clean-up and extraction proved to be very difficult and analyses of smokers' urine samples underlined the need for an effective clean-up procedure, efficient chromatography and a sensitive and selective method of detection. It was concluded that the developed HPLC method of analysis was inadequate for quantitative analysis of nicotine and its metabolites in urine.
38
Wood, Jennifer. "A study of the development of the adrenal gland in very low birthweight babies by gas chromatographic analysis of urinary steroid profiles". Thesis, The University of Sydney, 1995. https://hdl.handle.net/2123/26836.
Abstract (sommario):
The adrenal development in a group of very low birthweight (VLBW) neonates was studied over the first few months of life by using gas chromatographic and gas chromatographic-mass spectrometric urinary steroid profiling. The extraction method used was developed for use on neonatal urine which contains several unique and highly polar steroids.
At birth two zones are present in the human adrenal cortex, an inner zone (the fetal
adrenal zone), and an outer zone (the definitive adrenal cortex). Postnatally, over the first few months the fetal zone involutes, leaving the definitive zone which produces glucocorticoids and mineralocorticoids.
This study demonstrated the suppression of the fetal adrenal zone by exposure to postnatal glucocorticoid therapy, but was unable to determine any other factors influencing the decline of fetal zone steroid excretion. This study supported previous work that has shown that the production of steroids by the fetal zone does not decline during the first month in premature neonates, and indeed may not decline over the first few months. Large oscillations in the levels of fetal zone steroids excreted within individual subjects were observed.
The rapid changes which occur in the adrenal gland at this time make congenital adrenal hyperplasia (CAH) difficult to diagnose based solely on plasma steroid levels. In this study a urinary steroid (15a,17B—dihydroxy-pregnanolone) that had previously been suggested as a marker for neonatal CAH was detected in the urine of a VLBW neonate who showed no evidence of CAH.
39
Shadbolt, Sheila. "The use of ¹H-NMR analysis of urine to discriminate between calcium oxalate kidney stone patients and healthy controls". Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/6362.
Abstract (sommario):
Bibliography: leaves 105-111.NMR has been used to study the metabolites found in body fluids, like urine, in the past three decades. It has more recently been used to study a lare range of diseases and the toxicolgoical effect of drugs on animals, by looking at metabolite patterns in the urine. The major advanteges of using NMR are that it is fast, non-invasive, non-destructive and non-equilibrium pertubing technique, allowing the detection of a diverse range of compounds in a single experiment.
40
Lange, Tim Verfasser], Karlhans [Akademischer Betreuer] [Endlich, Karlhans Gutachter] Endlich e Sebastian [Gutachter] [Bachmann. "Identification and analysis of urine-derived exosomal miRNAs and BDNF / Tim Lange ; Gutachter: Karlhans Endlich, Sebastian Bachmann ; Betreuer: Karlhans Endlich". Greifswald : Universität Greifswald, 2020. http://nbn-resolving.de/urn:nbn:de:gbv:9-opus-35795.
41
Lange, Tim Verfasser], Karlhans [Akademischer Betreuer] [Endlich, Karlhans [Gutachter] Endlich e Sebastian [Gutachter] Bachmann. "Identification and analysis of urine-derived exosomal miRNAs and BDNF / Tim Lange ; Gutachter: Karlhans Endlich, Sebastian Bachmann ; Betreuer: Karlhans Endlich". Greifswald : Universität Greifswald, 2020. http://d-nb.info/1206688335/34.
42
Lange, Tim [Verfasser], Karlhans [Akademischer Betreuer] Endlich, Karlhans [Gutachter] Endlich e Sebastian [Gutachter] Bachmann. "Identification and analysis of urine-derived exosomal miRNAs and BDNF / Tim Lange ; Gutachter: Karlhans Endlich, Sebastian Bachmann ; Betreuer: Karlhans Endlich". Greifswald : Universität Greifswald, 2020. http://d-nb.info/1206688335/34.
43
Dinh, Nancy Vien. "An analysis of the accuracy and function of three presumptive methods used in forensic science for the detection of urine". Thesis, Boston University, 2012. https://hdl.handle.net/2144/12349.
Abstract (sommario):
Thesis (M.S.)--Boston UniversityThe presumptive detection of urine from evidence found at a crime scene can assist investigators in determining the events that occurred during the commission of the crime. The Jaffe test is a traditional method which relies on the detection of creatinine, a constituent of urine. In 2009, the Uritrace® test device was developed to detect the presence of creatinine in urine. In 2010, the RSIDTM-Urine immunochromatographic card was released as a method for detection of a reportedly more specific component of urine, Tamm-Horsfall protein. The significance of these various techniques lies in their capacity to accurately detect the respective urinary constituents to allow for a presumptive determination of urine. The objective of this study is to compare the three presumptive tests to determine how effectively and accurately each method could be used to detect their respective target molecules in urine. Areas of research interest include the area of the stain that is sampled, manipulation of buffer volumes, the level of cross-reactivity with non-urine samples, and the detection of nucleated epithelial cells in aged urine stains. It was discovered that, with regards to the Jaffe and Uritrace® methods, the area in which the known urine stain was sampled did not affect the result of the test; however that was not the case for RSIDTM-Urine. Decreasing the extraction volume for Uritrace® and RSIDTM-Urine did not inhibit positive results, implicating that it is possible to adequately perform either of the tests at lower levels of dilution. Jaffe and Uritrace® were shown to be susceptible to false positive signals, whereas RSIDTM-Urine was not. Nucleated epithelial cells were not detected in any of the aged urine stain samples, suggesting that the persistence of cellular material available for potential downstream DNA testing may be minimal. Photoimaging analysis was also used to assess the ease of interpretation of results using Uritrace®. An evaluation of all three methods revealed that although the Jaffe test is not the most specific method, it is the most practical and cost-effective method for the forensic detection of urine.
44
Tsai, Mon-Yo, e 蔡孟祐. "Analysis of Phenol In Water and In Urine". Thesis, 1993. http://ndltd.ncl.edu.tw/handle/63672126858091467266.
45
Ncube, Somandla. "Liquid phase microextraction of hallucinogenic compounds from human urine samples based on single hollow fibre followed by chromatographic determination". Thesis, 2016. http://hdl.handle.net/10539/21207.
Abstract (sommario):
A dissertation submitted to the Faculty of Science, University of the
Witwatersrand in fulfilment of the requirements for the degree of
Master of Science. University of the Witwatersrand, Johannesburg, March 2016A liquid phase microextraction based on single hollow fibre followed by liquid chromatographic determination was developed for the extraction and quantification of the hallucinogenic muscimol and its two precursors, tryptophan and tryptamine from urine samples. A multivariate design of experiment was used in which a half fractional factorial approach was applied to screen six potential factors (donor phase pH, acceptor phase concentration, supported liquid membrane composition, stirring rate, extraction time and salt content) for their extent of vitality on the extraction of muscimol, tryptophan and tryptamine using the developed method. Four factors were identified as essential for an enhanced enrichment of each of the three research analytes from diluted urine samples. The paired vital factors were then optimized using central composite designs where empirical quadratic response models were used to visualize the response surface through contour plots, surface plots and optimization plots of response output. When the muscimol-based optimum factor levels were applied for the simultaneous extraction of the three research analytes, a composite desirability of 0.687 was obtained implying that the set conditions were ideal for a combined extraction of the analytes from the donor phase into the acceptor phase across a supported liquid membrane impregnated with a carrier molecule. This was an acceptable result considering that only the optimized muscimol factor levels were set as universal factor values. Muscimol was the analyte of interest in this research. The composite desirability value was predicted by setting the extraction conditions to 20% (w/w) di-(2-ethylhexyl) phosphoric acid (DEHPA) in dihexyl ether (DHE) supported on the walls of a hollow fibre into a 200 mM HCl acceptor phase inside the hollow fibre from a 20% (v/v) diluted urine donor phase spiked in the 0.1 – 10 μg mL-1 analyte concentration range maintained at pH 4 and stirred at 800 rpm for 60 mins. Experimentally, average enrichments of 4.1, 19.7 and 24.1 were obtained for muscimol, tryptophan and tryptamine, respectively. iv The complexity of urine and the anionic nature of the carrier molecule embedded on the supported liquid membrane resulted in interfering peaks that could not be completely resolved from the analyte peaks. Thus matrix-based calibration curves were used to address matrix effects. Various statistical approaches were used to validate suitability of the developed method for its potential use in quantifying muscimol and its precursors from urine samples. These validation measures were used as a way of determining the method’s ability to maintain the extraction process at equilibrium over a specific range of analyte concentrations over a period of analyte existence in a urine sample. The r² values of the matrix-based linear regression prediction models ranged from 0.9933 to 0.9986. The linearity of the regression line of the matrixbased calibration for each analyte was directly linked to the analyte enrichment repeatability. Simultaneous analyte enrichment repeatability over a 0.1 – 10 μg mL-1 analyte spiking concentration ranged from an RSD value of 8.3% to 13.1%. Limits of detection were 0.021 μg mLˉ¹, 0.061 μg mL-1 and 0.005 μg mL-1 for muscimol, tryptophan and tryptamine, respectively. Other validation parameters that were considered included specificity (and selectivity), accuracy, robustness, extraction range and system suitability. The accuracy of the developed method was reported as the reproducibility of enrichment factor values over six spiking concentrations used in constructing matrix-based calibration curves. System suitability was limited to an HPLC-UV approach. Method suitability was addressed through a comparative summary in which the LOD, LOQ and r² values for the developed method were compared to other methods that have been used to extract muscimol from urine samples. The relevance or acceptability of the enrichment factor values obtained for the extraction of the three analytes was achieved by comparison with enrichment factor values of several compounds with similar polarity that have been extracted from urine samples using carrier-mediated hollow fibre liquid phase microextraction.
GR2016
46
Fu-Ren e 江福仁. "Mass Spectrometric Analysis of Benzodiazepins In Urine and Hair". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/40151268630350543257.
Abstract (sommario):
碩士中山醫學大學
醫學分子毒理學研究所
94
This study was developed urine and hair testing for nine benzodiazepins, include Diazepam、Nordiazepam、Oxazepam、Lora zepam、Nitrazepam、Temazepam、Flunitrazepam、Alprazolam、Triazolam. The hair testing was used GC-NCI/MS. The limit of detection for Flunitrazepam was about 3 pg/mg hair, Temazepam was 0.1 pg/mg hair, and others were 1 pg/mg hair. The concentration of real sample from the treatment center was about 70 pg/mg, but it was quit different for the BZD drugs patients which were about 10 pg/mg. The technologies of hair testing were transferred to GC-EI/MS urine testing. The limit of detection for Oxazepam、Lorazepam and Temazepam were about 0.1 ng/mL. Others drugs was about 1 ng/mL. For LC/MS/MS, We compared the sensitivity of ESI and APCI. The result show APCI is better than ESI for 10-100 folds. The APCI Positive ion＞APCI negative ion ≧ESI Positive ion＞ESI negative ion. However, the real sensitivity of APCI and ESI were decrease 10 fold by urine matrix.
47
Lin, Shih-Shan, e 林詩珊. "Analysis of cathinones in urine by chromatography/mass spectrometry". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/35g9tu.
Abstract (sommario):
碩士中央警察大學
鑑識科學研究所
106
Numerous criminal problems are derived from drug abuse, such as social security and lose of social cost. Especially, the sale and recreational use of New psychoactive substances (NPS) increase rapidly in recent years. NPS are developed to mimic the effects of known illegal drugs of abuse in order to evade criminal penalties. Because its growth and development is too fast, control of NPS is not easy, making the resulting social harm is very serious. NPS have become one of important issues for drug control. It is a challenge for examination of all NPS. In this study, the mass spectrums library of synthetic cathinone (a kind of NPS) in LC-QTOF/MS has been built. With urine sample as matrix, we have been evaluated the method for analysis of synthetic cathinone. In method validation, we evaluates calibration curves, LOD, LOQ, recovery and intra- inter-day assay. Calibration curves of synthetic cathinone are linear (R2 >0.99) between 10-1000 ng.ml. Recovery efficiencies range from 82.91 to 103.31% except from 3-FMC. Matrix effects range from -20% to 20% except for methylone (35%) and 3-FMC (-58%). In this study, we hope the established method for analysis of synthetic cathinone could effectively combat emerging drugs
48
Liu, Hsu-Che, e 劉旭哲. "Patent Analysis of Urine Sensing Technologies for Kidney Disease". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/n9wnar.
Abstract (sommario):
碩士國立臺灣科技大學
專利研究所
107
The present study is to investigate the life cycle, industrial development, and the innovation breakthrough point in the field of urine sensing technology for kidney disease by analyzing present global patents. The method of present study is to analyze the patents systematically by using the technology of patent search, patent analysis and patent map, and hopefully to provide merited information to the existing companies or newcomers in the field of urine sensing technology for kidney disease. The results indicated that the development of urine sensing technology for kidney disease is in a pause status due to the applicants are seeking a good opportunity to enter the global market. For the development of sensing technologies, there is still a room for improvement depend on the different technologies and different groups of client.
49
Chia-HungHsia e 夏嘉鴻. "Development of Home Health Checkup System for Urine Analysis". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/yj2xar.
50
Lung, Su-Yi, e 蘇意隆. "Evaluation of Bioeletrical Impedance Analysis for Intravesical Urine Volume Assessment". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/97654111336974928193.
Abstract (sommario):
碩士南開科技大學
福祉科技與服務管理所
99
Purpose: this investigation tried to apply bio-electrical impedance analysis (BIA) method to assess intravesical urine volume.Method: this study applied a healthy subject’s measured impedance to understand the detecting ability of BIA to assess intravesical urine volume,the sensitivity and confidence of two kinds of detecting electrodes, such as silver and stainless steel electrodes,fitness and accuracy of a regression equation related impedance to intravesical urine volume, the standard operating procedure of intravesical urine volume assessment by BIA. Results: (1) the differences of impedance corresponded to intravesical urine volume of 800ml and 0 ml could be detected by silver and stainless steel electrodes,the impedance was increased when intravesical urine volume was reduced.。Using silver and stainless steel electrodes to assess intravesical urine volume ranged from 800 to 0ml were respectively corresponded in impedance 7.9%,12.5%, the standard deviation were 7.09~7.81 and 1.54~1.99 Ohms。The result indicated that the quantification ability of stainless steel electrodes were better than silver electrodes.(3) regression equation obtain from using stainless steel electrodes had better fitness and F test result, which prediction also had higher explain ability.