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Dépistage des infections du tractus urinaire par méthode moléculaireVingataramin, Laurie January 2014 (has links)
Chaque année, environ 175 millions de personnes souffrent d’infection du tractus urinaire (ITU) dans le monde. Pour diagnostiquer une ITU, une culture d’urine est réalisée mais nécessite un long délai. Pendant ce temps les patients sont souvent traités avec un antibiotique à large spectre qui peut entrainer des complications et contribuer à l’augmentation du nombre de bactéries résistantes. La plupart des échantillons reçus au laboratoire sont négatifs (≤10[indice supérieur 5] ufc /mL) ou contiennent Escherichia coli. Nous avons mis au point une méthode de dépistage rapide des échantillons positifs afin de sauver des coûts et éviter des complications.
D’abord un protocole d’extraction d’ADNg a été élaboré avec la même efficacité pour tous les microorganismes. Cette méthode, appelé EtNa, chauffe le microorganisme dans une solution de 70 % éthanol et NaOH. Cette solution permet l’adsorption de l’ADN directement sur une colonne de silice afin de favoriser sa purification par un robot pipeteur. Elle a été comparée favorablement avec d’autres méthodes retrouvées dans la littérature et trousses commerciales, mais a l’avantage d’extraire les bactéries Gram positifs, Gram négatifs et levures avec une efficacité similaire et ce, avec un même protocole simple et sans produits chimiques toxiques.
La deuxième étape du projet a été de mettre au point une méthode pour dépister les microorganismes pouvant causer les ITU en utilisant la PCR en temps réel pour amplifier le gène d’ARNr 23S des bactéries et 28S des levures. Grâce à une stratégie innovatrice de dénaturation des sondes, le pathogène peut être détecté et partiellement identifié. Une valeur seuil permettant de distinguer les échantillons positifs a été évaluée et correspond à un Cp de 26 (10[indice supérieur 5] ufc/mL). Un témoin interne est utilisé et permet de contrôler l’extraction et l’amplification. La méthode de dépistage a été éprouvée in vitro avec des souches de bactéries et levures, puis essayée avec quelques échantillons d’urines en provenance de la clinique. Puisque les résultats obtenus étaient très encourageants, l’analyse d’autres échantillons est importante pour faire une validation complète.
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An Examination of Maternal Stress and Secondhand Smoke Exposure on Perinatal Smoking StatusDamron, Karen R. 01 January 2016 (has links)
The median prevalence of smoking among women of childbearing age in the United States is 22.4%. Of women who identify themselves as smokers in the three months prior to conception, 55% quit during pregnancy; however, 40% of those who quit relapse and return to smoking within six months after delivery. Smoking has been identified as an important means of stress management among smokers in general, and though limited to the perinatal period, pregnancy-specific stress adds to a woman’s typical day-to-day stress burden. Little data exists as to the effect of SHS exposure on smoking status during pregnancy and the impact of SHS exposure on the maternal perception of stress is unknown. Due to limited evidence, a critical need exists to examine the relationships of perceived maternal stress, SHS exposure, and perinatal smoking status in order to better understand perinatal smoking behaviors.
The purposes of this dissertation were to: 1) evaluate the literature examining the relationship between the variables of maternal stress, SHS exposure, and perinatal smoking status; 2) determine the reliability and validity of the Everyday Stressors Index (ESI) use in pregnant women; and 3) to investigate the impacts of maternal perception of everyday stress, and SHS exposure on perinatal smoking status.
Evidence obtained from the critical review of the literature supported an association between psychosocial stress and smoking during pregnancy or postpartum. Little information regarding the role of SHS exposure on perinatal smoking status was discovered. Psychometric testing of the ESI demonstrated strong internal consistency reliability, and factor analysis yielded three factors capturing three important domains of everyday stress. SHS exposure emerged as the most significant predictor of smoking status. Persistent smokers/relapsers had the highest ESI scores, followed by quitters, and then nonsmokers. While ESI means decreased in all smoking status groups from the first to the third trimester, the magnitude of decrease was not predictive. A significant interaction effect of SHS exposure in the home and decrease in ESI score occurred in the quit group only with quitters 1.14 times more likely to experience a decrease in ESI score compared to smokers/relapsers.
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The development of direct infusion mass spectrometry method for analysis of small metabolites in urineDe Kock, Neil 03 1900 (has links)
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.
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Relative bioavailability of terbutaline to the lungs following inhalation using different methodsAbdelrahim, M. E. A. January 2009 (has links)
The primary aim was to validate and implement a urinary pharmacokinetic method for terbutaline to determine the relative lung and systemic bioavailability following inhalation and to measure the in-vitro characteristics of the emitted dose by these inhalation methods. Two new robust, accurate and sensitive high performance liquid chromatography methods for the determination of terbutaline in aqueous and urine samples were validated in accordance with the FDA and ICH guidelines. Terbutaline was extracted using solid phase extraction with salbutamol and bamethane as internal standards. The accuracy, precision, lower limit of detection and recovery for both methods were within recognized limits. The in-vitro characteristics of terbutaline sulphate inhalers were measured according to standard compendial methodology as well as adaptation of this methodology to simulate routine patient use. The dose emission of terbutaline sulphate from a Bricanyl Turbuhaler was determined using an inhalation volume of 4 L at inhalation flows of 10-60 L min-1. The particle size distribution was measured using an Anderson Cascade Impactor (ACI) with a mixing inlet valve to allow measurement at different flows. A steady increase in total emitted dose (TED) and the fine particle dose (FPD) was observed as the inhalation flow increased thereby highlighting the flow dependent dose emission characteristics of the Turbuhaler. The in-vitro dose emission characteristics of terbutaline sulphate from Bricanyl MDIs were measured according to the standard compendial methodology at a flow of 28.3 L min-1 using a 4 L inhalation volume. The TED and particle size distribution of terbutaline sulphate from the Bricanyl MDI were determined alone and with different spacers [AeroChamber Max (AMAX), AeroChamber Plus (APLUS), Fisonair and Nebuhaler]. The TED from the MDI alone was significantly higher than all MDI+spacers (p<0.001). The MDI with APLUS resulted in the smallest mass median aerodynamic diameter (MMAD) and the highest fine particle fraction (FPF). The MDI with AMAX resulted in the highest FPD. The in-vitro characteristics of terbutaline sulphate from Bricanyl respules using the Aeroneb Pro (vibrating mesh) and Sidestream jet nebulisers were determined by the CEN methodology and the Next Generation Impactor (NGI) methodology. The Aeroneb Pro was found to have significantly better aerodynamic properties than the Sidestream. The results from the NGI method were significantly different from the CEN method suggesting further evaluation of both methods. Cooling the NGI decreased the evaporation effect. Twelve healthy volunteers (6 females) completed in-vivo urinary terbutaline pharmacokinetic studies to determine the relative bioavailability following inhalation. The differences between the amounts excreted 0.5, 1, 2, 4, 6 and 24 hour post inhalation from a Bricanyl MDI (I) and oral (O) dosing of 500 µg terbutaline sulphate and with the co-administration of oral charcoal (IC and OC, respectively) were studied. No terbutaline was found in OC samples. The amount of terbutaline excreted 30 minutes post I and IC were significantly (p<0.001) higher than post O suggesting that the amount of terbutaline excreted 30 minutes post dosing can be used as an index of the lung deposition. The amount of terbutaline excreted 24 hour post I was significantly (p<0.01) higher than post O suggesting that the amount of terbutaline excreted 24 hour post dosing can be used as an index of the relative systemic bioavailability. The dose response relationships and the low inter and intra-subject variability studies confirm the feasibility of this method. To demonstrate the application of the method the effect of inhalation technique on the lung and systemic bioavailability following inhalation from a dry powder inhaler was evaluated. The effect of different spacers on the dose emitted from the Bricanyl MDI and the effect of different nebulisers on the dose emitted were also studied using twelve healthy volunteers (6 females) for each study. A fast inhalation flow using the Bricanyl Turbuhaler resulted in significantly higher amounts of terbutaline excreted 0.5 and 24 hour post dosing (2 doses of 500µg terbutaline sulphate from Bricanyl Turbuhaler) than slow inhalation flow (p<0.001). The Bricanyl MDI alone resulted in a significantly higher amount of terbutaline excreted 24 hour post dosing (2 doses of 250µg terbutaline sulphate from Bricanyl MDI) and significantly lower amounts excreted 30 minutes post dosing than the MDI+Spacers. The AMAX provided a greater amount of urinary terbutaline excreted 30 minutes post dosing than the APLUS and Nebuhaler. The Aeroneb Pro resulted in significantly higher amounts of terbutaline excreted 0.5 and 24 hour post dosing (1 dose of 5mg/2ml terbutaline sulphate from Bricanyl respule) than a Sidestream Jet nebuliser (p<0.001). Further application of the method was demonstrated by 12 (6 female) COPD non-invasive mechanically ventilated patients. One dose of 2mg in 0.8ml terbutaline sulphate respiratory solution from Aeroneb Pro and one dose of 5mg in 2ml terbutaline sulphate respiratory solution from Sidestream jet nebuliser resulted in a similar amounts of urinary terbutaline excreted 0.5 and 24 hour post dosing. The results were consistent with the results of the ex-vivo study performed on the same patients. The thesis highlights extension of the urinary pharmacokinetic method following inhalation to terbutaline and its application in volunteer and patient studies.
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Osmotic response element binding protein (OREBP) is an essential regulator of urine concentrating mechanism and renal protectionLam, Ka-man, Amy., 林嘉敏. January 2004 (has links)
published_or_final_version / abstract / toc / Molecular Biology / Doctoral / Doctor of Philosophy
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Water consumption and factors influencing hydration statusJalali, Ejlal January 2012 (has links)
Objectives. This study aimed to provide data on water intake from food and beverages of free-living adults in their natural environment, and investigate how this is affected by physiological, psychological, social and environmental factors. A further aim was to monitor the hydration status of free-living adults and relate this data to water intake. Methods The consumption of all food and beverages was recorded in a diary over three consecutive days by 80 healthy adults (40 males, 40 females), aged 18 to 65 years, who were instructed to continue their normal eating and drinking habits and lifestyles throughout the study. The data was analysed to determine total daily water intake and how this was affected by time of day, day of the week, presence of others, location of consumption, age and subjects mood. A further 20 healthy subjects (10 males, 10 females) repeated these procedures but also had blood samples taken for monitoring of blood indices (haemoglobin concentration, haematocrit, sodium concentration, and potassium concentration) and provided urine samples for the measurement of urine indices (volume, colour, specific gravity, osmolality and sodium, potassium, chloride, and creatinine concentrations). Results The total volume of water consumed by the 80 subjects was 2229 882 ml/day (mean standard deviation). Females tended to consume more water than males (2402 827 ml/day vs 2056 911 ml/day, P = 0.079). Similar volumes were consumed by the additional 20 subjects in the hydration status study. Females appeared euhydrated; males appeared mild dehydrated, having a higher morning and 24-hour urine specific gravity and osmolality than females (P < 0.05, respectively). Conclusions The mean daily total volume of water consumed by females in this study was greater than the adequate intake value set by the European Food Safety Authority; for males it was lower. Females were euhydrated during the study but males tended to be mild dehydrated, reflecting their comparative water intakes.
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Recherche de biomarqueurs précoces de diagnostic de la néphropathie diabétique / Search for early candidate biomarkers for diabetic nephropathyBen Ameur Siala, Randa 25 February 2011 (has links)
La néphropathie diabétique (ND) est l'une des complications graves du diabète. Elle affecte environ 30% des patients diabétiques. La microalbuminurie est actuellement l'élément diagnostique principal de la survenue de la ND mais manque de spécificité et précocité. Plusieurs études ont été consacrées à la recherche de nouveaux biomarqueurs (BM) de la ND par des approches protéomiques. Nous avons montré dans la phase initiale de notre travail que si de nombreux candidats BM avaient été identifiés, leur nature ne faisait pas consensus et que de nombreuses études, de par leur conception, ne pouvaient identifier de BM plus précoces que l'albumine. Partant de ce constat, nous avons sélectionné une cohorte originale de diabétiques de type 1 normoalbuminuriques considérés à risque de développer la ND, sur la base de l'apparition d'une microalbuminurie consécutive à un test d'effort. Une cohorte contrôle a été aussi constituée. Dans la première partie de notre travail, nous avons comparé par électrophorèse bidimensionnelle les protéomes urinaires des patients des deux coho rtes. Les BM candidats ont été ensuite identifiés par spectrométrie de masse. L'analyse fonctionnelle de ces protéines a montré que certaines sont impliquées dans la cascade de la coagulation et les mécanismes de dysfonctionnement endothélial. Le caractère diagnostique de ces protéines a été validé dans les mêmes cohortes de patients par des expériences de Western-blot. La compréhension de la nature et de la fonction physiologique des BM candidats identifiés nous a permis de mieux appréhender les mécanismes moléculaires de la pathogénèse de la ND et d'identifier des candidats biomarqueurs plus précoces que l'albumine. Ces résultats sont présentés sous la forme d'un projet d'article .La deuxième partie de notre travail expérimental est constituée d'études préliminaires visant à la recherche de protéines spécifiques urinaires, néphrine et isoformes de l'adiponectine, afin d'évaluer leur potentiel diagnostique. 1 Ben Ameur R. et al Proteomic approaches for discovering biomarkers of diabetic nephropathy. Nephrol Dial Transplant 25, 2866-752 Ben Ameur R. et al Identification of early candidate biomarkers for diabetic nephropathy by urine proteomic analysis. To be submitted / Diabetic nephropathy (DN) is one of the most serious complications of diabetes. It affects about 30% of diabetic patients. Microalbuminuria is currently the main available marker for DN risk, but has inadequate specificity and precocity. Several published studies intended to research new biomarkers (BM) of DN by proteomic approaches. We have shown1 that, if several candidate BM were claimed, there was no consensus about their nature and that a number of studies could not identify BM earlier than albumin because of the study design. Thus, we have selected an original cohort of type 1 diabetic patients considered at risk of developing DN, on the basis of urinary albumin excretion after an exercice test. A control cohort was also enrolled. Using 2D gel electrophoresis we compared the urinary proteomes of patients from both cohorts. Then, candidate BM were identified by mass spectrometry. Functional analysis of these proteins showed that some are involved in the coagulation cascade and in mechanisms of endothelial dysfunction. The diagnostic potential of these proteins was validated by Western blotti ng. The nature and physiological function of candidate biomarkers allowed to better understand the molecular pathogenic mechanisms of DN. Results from this part of the work are shown in the form of an article2. Preliminary studies to assess the diagnostic potential research of specific urinary proteins (nephrin and different isoforms of adiponectin) are also presented.1 Ben Ameur R. et al Proteomic approaches for discovering biomarkers of diabetic nephropathy. Nephrol Dial Transplant 25, 2866-752 Ben Ameur R. et al Identification of early candidate biomarkers for diabetic nephropathy by urine proteomic analysis. To be submitted
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Anomalies cytogénétiques impliquées dans la carcinogénèse des tumeurs urothéliales et application clinique / Cytogenetic Abnormalities of Urothelial Carcinomas Analysis and Clinical Application for Urine Detection Using CGH ArrayLarré, Stéphane 30 November 2010 (has links)
Les carcinomes urothéliaux représentent la 4ème cause de cancer chez l'homme après les cancers de la prostate, du colon et du poumon. Leur incidence est en augmentation de plus de 50% depuis 25 ans. Ce cancer présente principalement deux formes, une superficielle (70% des cas) de bon pronostic et une invasive (30%) de mauvais pronostic. Les formes superficielles nécessitent une surveillance active rapprochée afin d'identifier les récidives fréquentes et l'évolution vers un stade invasif. Cette surveillance fait principalement appel à la cystoscopie et engendre morbidité et cout importants. Une alternative à la cystoscopie est possible à l'aide de tests de détection urinaire des cellules cancéreuses, mais leur sensibilité jusqu'à présent n'est pas suffisante pour une utilisation en pratique courante. Notre but a été de développer un outil de détection urinaire des tumeurs urothéliales.Matériel, Méthode et RésultatsLes tumeurs urothéliales étant très instables sur le plan génétique, le travail a initialement consisté à faire la synthèse des anomalies cytogénétiques retrouvées dans la littérature. Les anomalies les plus pertinentes ont été sélectionnées et une puce de CGH en a été développée comprenant 341 clones (BAC) répartis sur l'ensemble des chromosomes. Cette puce intitulée BCA-1 a été développée en collaboration avec la société ArrayGenomics (Voisins Le Bretonneux, France). La validité de ce test a été confirmée sur 10 lignées cellulaires tumorales et bénignes.Notre travail a ensuite consisté à étudier la valeur ajoutée de cette puce en pratique clinique. Pour ce faire, une cohorte de 163 patients porteurs de tumeurs urothéliales et de témoins a été constituée. Les urines ont été prélevées et analysées en utilisant la puce BCA-1. Un logiciel a été développé sous filemaker pro afin de permettre une saisie uniforme et détaillée des données cliniques et de prendre en considération le caractère complexe de la prise en charge de ces tumeurs.Le test urinaire utilisant la puce de CGH a montré une excellente performance diagnostique avec une sensibilité de 96% et une spécificité de 98% dans les tumeurs vésicale, et une sensibilité de 100% tumeurs du haut appareil urinaire.Enfin, le test a aussi permit de caractériser le caractère agressif ou non agressif des tumeurs sur le plan cytogénétique. Cette caractérisation est fortement corrélée avec le stade anatomopathologique et un troisième aspect de notre travail a montré que la détermination cytogénétique de l'agressivité des tumeurs prédisait l'évolution défavorable des tumeurs du haut appareil urinaire. Notre travail a permis le développement et l'analyse d'un nouveau test de dépistage urinaire des tumeurs urothéliales permettant le diagnostic urinaire de ces tumeurs et la caractérisation de leur caractère agressif éventuel, ainsi que le développement d'un logiciel de saisie et d'analyse des données cliniques. / Urothelial carcinomas are the 4th cause of cancer in men, following prostate, colon and lung cancer. An increase of 50% in its incidence was observed on the last 25 years. This cancer presents two types, a superficial type (70% of the cases) of good prognosis and an invasive type (30% of the cases) of bad prognosis. Superficial type require an active monitoring to identify recurrences and evolution to an invasive stage. This follow up is performed using cystoscopy and leads to some level of morbidity and a high cost. An alternative to cystoscopy is possible using urine test to detect cancer cells, but they are lacking of sensitivity to be used instead of cystoscopy in clinical practice. Our goal was to develop a urine detection tool of urothélial carcinomas.Material and MethodsUrothelial carcinoma usually present with a high level of genetic instability. We first analyse literature so to identify most relevant cytogenetic abnormalities that occur in urothélial carcinomas. A CGH array chip was designed using 341 clones (BAC) that were selected according to initial analysis. This chip called BCA-1 covers the whole genome and was developed in collaboration with ArrayGenomics (Voisins Le Bretonneux, France).ResultsThis test has shown a good efficacy on a preliminary study of cytogenetic analysis on 10 cancerous and benign bladder cell lines. The Chip was then assessed in clinical practice on a series of 163 patients diagnosed with or without urothelial cancer. Urines were collected and analysed using the BCA-1 chip. A software was designed to favour homogeneous and detailed clinical data collection and take into consideration the complex management of the tumours.The test using the CGH chip as shown an excellent diagnosis performance with a sensitivity of 96% and a specificity of 98% for bladder cancer detection, and a sensitivity of 100% on upper urinary tract detection.Finaly, the test was able to define the grade of the tumour according to cytogenetic loci affected. This grade was strongly correlated with the pathology score and could be used to predict outcomes in upper urinary tract carcinomas. Our work lead to the developpement and the analysis of a new urothélial carcinoma urinary detection test, to the identification of the agressivity of the tumour, and to the development of an analysis and data entry software for clinical details.
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Mercury leaching from dental amalgam fillings and its association with urinary zincZanager, Afaf Mohamed January 2019 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Mercury (Hg) is an example of a toxic metal that is not essential for nutrition. It exists in organic and inorganic forms in seafood and vapour from dental amalgam fillings respectively. Elemental mercury (Hg0) from dental amalgam was the focus of this study. Dental amalgam is one of the most commonly used dental filling materials and has been used for over 150 years. It is composed of Hg0 (approximately 50%) combined with other metals such as copper and zinc (Zn). These fillings give off Hg0 vapour throughout their existence, and is further enhanced by activities such as chewing, grinding of teeth and drinking hot liquids. Mercury consumption can lead to Zn loss or deficiency, and is reported to displace Zn and copper. Several European nations have outlawed the use of amalgam as a restorative material due to controversies regarding its safety in children, women of childbearing age and individuals with renal disease. Moreover, various studies have reported correlations between the number of amalgam fillings and Hg concentration in blood plasma, urine, faeces, saliva and different organs. Blood, urine, and hair mercury levels are used to predict possible health effects that may be caused by the different forms of Hg. Urine Hg is used to test exposure to metallic Hg0 vapour and inorganic Hg forms.
This study aimed to evaluate the effects of Hg0 from dental amalgam restorations on the status of Zn in the urine. This was done by determining the concentrations of Hg0 in urine, buccal cells and the oral cavity, and its relationship with urinary Zn concentrations in the same individuals. Samples of urine, buccal tissues, chewing gum and completed questionnaires were collected from the participants (women
and men) at the dental clinics in Tygerberg Hospital (TBH), Cape Town. Samples were analyzed using inductively coupled plasma mass spectrometer (ICP-MS).
Findings from this study show that there was a correlation between levels of urinary Hg0 and urinary Zn (p=0.02). However, urinary Hg0 did not predict the amount of urinary Zn. Also, no relationship was found between levels of Hg0 in buccal swab or the chew test samples and urinary Zn level. There was a significant difference between females and males in the level of urinary Zn, men had higher levels of Zn excreted in the urine than females (p=0.05). However, there was no significant difference in the level of urinary Hg0 between males and females. The number of fillings (4-7) and age of fillings were significantly associated with urinary Hg0 level (p˂0.05), while smoking ˃15 cigarettes/day increased the level of Hg0 in buccal swab samples (p=0.002). We were not able to demonstrate a causal effect of Hg0 leaching on urinary zinc levels.
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Investigação de compostos orgânicos voláteis em amostras de suor como biomarcadores no diagnóstico de câncer / Investigation of volatile organic compounds in sweat samples as biomarkers in cancer diagnosis.Monedeiro, Fernanda Ferreira da Silva Souza 23 May 2018 (has links)
Processos metabólicos naturais no organismo humano levam à formação de substâncias como compostos orgânicos voláteis (VOCs), de modo que, em um quadro patológico, processos diferenciados podem ocorrer nas células, fazendo com que um conjunto diferente de compostos seja produzido. Com esta hipótese, VOCs podem ser analisados em amostras biológicas com a intenção de se verificar alterações em seus perfis que sejam indicativos de certas patologias. No presente estudo, foi selecionado o suor como matriz, amostra de coleta simples e não-invasiva, de composição menos complexa e relacionada aos níveis sanguíneos e emanações da pele. Adicionalmente, foram também analisadas amostras de urina, para obtenção de dados comparativos. O presente estudo compreendeu amostras de voluntários saudáveis (grupo controle-C) e com diagnóstico de câncer confirmado (grupo positivo- P). As amostras de suor foram coletadas com o dispositivo PharmChek®, após, o patch foi removido, inserido em frasco e os VOCs isolados com emprego de técnica otimizada de Headspace estático (HS). Para as amostras de urina, estas foram analisadas com e sem tratamento por ?-glucuronidase. Perfis de VOCs foram obtidos por análise por cromatografia gasosa acoplada a espectrometria de massas (GC-MS) para todas amostras. A tentativa de identificação dos compostos detectados foi feita por busca na biblioteca NIST08 e uso do software AMDIS32. Diferenças qualitativas (teste chi-quadrado, p<<0,01) e quantitativas (teste U de Mann-Whitney, p<<0,01) foram avaliadas entre os perfis do grupo controle e positivo. Para o suor foram selecionados os potenciais biomarcadores pentanal, hexanal, heptanal, octanal, limoneno, 2-etil-1-hexanol, 1-undeceno, fenol, 2,6-dimetil-7-octen-2-ol (DMOL), nonanal, decanal e tridecano; para a urina, fenol e DMOL, hidrólise-dependentes, foram selecionados. Método HS-GC-FID (acoplado a detector por ionização de chama) foi desenvolvido e validado segundo a RDC 27/2012 da ANVISA, para ambas amostras. No suor, os analitos apresentaram limites inferiores de quantificação (LIQ) de 1 ng/adesivo, 5 ng/adesivo para o fenol; na urina foram de 2 ng mL-1 para o DMOL e 10 ng mL-1 para o fenol. Linearidade foi observada para faixa de 2 a 150 ng/adesivo e, 2 e 5 a 400 ng mL-1 na urina. No suor, a precisão variou de 0,08 a 12,35% e os analitos foram demonstrados estáveis para os ensaios realizados. Curvas ROC (Receiver Operating Characteristic) foram avaliadas e áreas sob a curva foram todas próximas a 1, com valores cut-off de 1,71 a 35,44 ng/adesivo no suor e 8,71 e 52,86 ng mL-1 na urina. 2-etil-1-hexanol se demonstrou negativamente correlacionado com o estágio clínico em adenocarcinomas (rô= -0,527) e DMOL, no suor, e aldeídos C5-C8 positivamente relacionados ao estágio do câncer de próstata (rô= 0,779 e 0,684, respectivamente). Conclui-se, portanto, que o método apresentado se mostrou eficiente, contudo, prático e de baixo custo, e os resultados obtidos corroboram para ideia da determinação de VOCs como promissora ferramenta auxiliar de diagnóstico no câncer. / Natural metabolic processes in the human body lead to the formation of substances such as volatile organic compounds (VOCs), so that, in a pathological context, differentiated processes can occur in the cells, causing a different set of compounds to be produced. With this hypothesis, VOCs can be analyzed in biological samples with the intention to verify changes in their profiles that are indicative of certain pathologies. In the present study, sweat was selected as the matrix, due simple and non-invasive collection, with lower complexity composition and related to blood levels and skin emanations. In addition, urine samples were also analyzed to obtain comparative data. The present study comprised samples from healthy volunteers (control-C group) and individuals with confirmed cancer diagnosis (positive-P group). The sweat samples were collected with PharmChek® device, next, the patch was removed, inserted in a vial and the VOCs were isolated using an optimized Static Headspace (HS) technique. For urine samples, these were analyzed with and without ?-glucuronidase treatment. VOC profiles were obtained by gas chromatography coupled to mass spectrometry (GC-MS) for all samples. The attempt to identify the detected compounds was made by searching the NIST08 library and using the AMDIS32 software. Qualitative differences (chi-square test, p << 0.01) and quantitative tests (Mann-Whitney U test, p << 0.01) were evaluated between the profiles of the control and positive groups. For the sweat, the potential biomarkers pentanal, hexanal, heptanal, octanal, limonene, 2-ethyl-1-hexanol, 1-undecene, phenol, 2,6-dimethyl-7-octen-2-ol (DMOL), nonanal, decanal and tridecane; for urine, phenol and DMOL, both hydrolysis-dependent, were selected. HS-GC-FID (coupled to flame ionization detector) method was developed and validated according to RDC 27/2012- ANVISA, for both samples. In sweat, the analytes presented limits of quantification (LOQ) of 1 ng/patch, 5 ng/patch for phenol; in urine were 2 ng mL-1 for DMOL and 10 ng mL-1 for phenol. Linearity was observed for the range of 2 to 150 ng/patch and, 2 and 5 to 400 ng mL-1 in urine. In sweat, the precision ranged from 0.08 to 12.35% and the analytes were shown to be stable for the assays performed. Receiver Operating Characteristic (ROC) curves were evaluated and areas under the curve were all near to 1, with cut-off values of 1.71 to 35.44 ng/patch in sweat and 8.71 and 52.86 ng mL-1 in urine. 2-ethyl-1-hexanol was shown to be negatively correlated with the clinical stage in adenocarcinomas (rho= -0.527) and DMOL, in sweat, and C5-C8 aldehydes sum, positively related to the stage of prostate cancer (rho= 0.779 and 0.684, respectively). It was concluded, therefore, that the method presented proved to be efficient, however, practical and low cost, and the results corroborate to the idea of VOCs determination as a promising diagnostic tool for cancer diagnosis.
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