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Determination of the quality of environmental water using GC-MS based faecal sterol analysis / Chantel SwanepoelSwanepoel, Chantel January 2014 (has links)
Faecal indicator bacteria have traditionally been used in the detection of faecal pollution in water, but due to concerns about the lack of reliability of these indicators, alternative methods have been developed. One of which is the detection of sterols present in human and animal excreta via GC-MS analysis of water in this study. The Szűcs method was used to detect six target sterols (coprostanol, cholesterol, dehydrocholesterol, stigmasterol, β-sitosterol, and stigmastanol) in environmental water samples. An initial study was done by analysing raw sewage and effluent (human faecal sterol biomarkers) and water samples were spiked with excreta from cattle, chickens, horses, pigs, and sheep to determine faecal sterol fingerprints. The method was evaluated for quantitation and differences between the water samples from each species. Following liquid-liquid extraction, silylation and derivatization, samples were analysed by GC-MS. Standard curve assays were linear up to 160ng and the limit for quantification was 20ng. The human faecal sterol biomarker was coprostanol, while herbivore profiles were dominated by terrestrial sterol biomarkers (stigmasterol and stigmastanol). Sterol fingerprints and differences in concentrations of sterols between various animals and between animals and humans occurred, providing the opportunity to determine whether faecal pollution was from humans or from animals. The method proved sensitive enough to evaluate faecal contamination in environmental water. Groundwater was collected from bore-holes and surface water samples were collected from the Baberspan Inland Lake. Physico-chemical parameters analysed indicated that pH for surface water samples was above 6.9. The total dissolved solids (TDS) in groundwater indicated that the water was not suitable for human consumption, but could be used for livestock watering. Surface water electrical conductivity (EC) and inorganic nitrates was too high to be used for irrigational purposes. Nitrates in groundwater were too high to be consumed by humans. In groundwater, the total
coliform target water quality range (TWQR) was exceeded at 53% of sites analysed and faecal coliform TWQR were exceeded at 77% sites. Surface water samples complied with TWQR with regards to faecal coliforms for full contact recreational activities and livestock watering. The TWQR for E. coli, with regards to full contact recreational activities, was within a safe range for surface water. Faecal streptococci were found in 85% of groundwater sampling sites. And surface water faecal streptococci counts exceeded the TWQR for full contact recreational activities. There is no TWQR for faecal sterols in water, but concentrations of cholesterol and coprostanol was found at three of the groundwater sites analysed. This indicates faecal contamination from possible animal and human origin. Surface water samples analysed showed that the Harts River water is clean and free of faecal sterols, while the water analysed from the inflow, hotel and outflow, cholesterol eluted, which showed faecal contamination, possibly from animals. Faecal sterol markers could be detected in groundwater and surface water, adding an extra dimension to determining the quality of water systems. An optimization and sensitivity study of the method was done on waste water treatment plant (WWTP) raw sewage and effluent. The WWTP sample analysed form Potchefstroom and Carletonville WWTP yielded all six target sterols in the raw sewage water samples, but no sterols eluted in the effluent samples. The raw sewage water sample taken from the Fochville WWTP yielded all six target sterols as well, however, the effluent yielded an unknown compound as well as cholesterol. An alternative study was done where the effluent sample volume was increased. By increasing the volume of water, one can possibly increase the amount (“load”) of sterols extracted and analysed, resulting in a higher abundance of target sterols. By using the target qualifier ions of the six target sterols, and the GC-TOF/MS software, the target sterols could still be qualitatively determined. Optimal volume for raw sewage is 300 ml water sample as this is enough to yield all 6 target sterols. For optimum water quality monitoring via faecal sterol analysis of effluent and other
environmental samples, at least 1L sample volume needs to be collected and analysed. The methods described here can be applied to the analysis of environmental water samples. The technical advantages also make it suitable for routine environmental monitoring of faecal pollution. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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Determination of the quality of environmental water using GC-MS based faecal sterol analysis / Chantel SwanepoelSwanepoel, Chantel January 2014 (has links)
Faecal indicator bacteria have traditionally been used in the detection of faecal pollution in water, but due to concerns about the lack of reliability of these indicators, alternative methods have been developed. One of which is the detection of sterols present in human and animal excreta via GC-MS analysis of water in this study. The Szűcs method was used to detect six target sterols (coprostanol, cholesterol, dehydrocholesterol, stigmasterol, β-sitosterol, and stigmastanol) in environmental water samples. An initial study was done by analysing raw sewage and effluent (human faecal sterol biomarkers) and water samples were spiked with excreta from cattle, chickens, horses, pigs, and sheep to determine faecal sterol fingerprints. The method was evaluated for quantitation and differences between the water samples from each species. Following liquid-liquid extraction, silylation and derivatization, samples were analysed by GC-MS. Standard curve assays were linear up to 160ng and the limit for quantification was 20ng. The human faecal sterol biomarker was coprostanol, while herbivore profiles were dominated by terrestrial sterol biomarkers (stigmasterol and stigmastanol). Sterol fingerprints and differences in concentrations of sterols between various animals and between animals and humans occurred, providing the opportunity to determine whether faecal pollution was from humans or from animals. The method proved sensitive enough to evaluate faecal contamination in environmental water. Groundwater was collected from bore-holes and surface water samples were collected from the Baberspan Inland Lake. Physico-chemical parameters analysed indicated that pH for surface water samples was above 6.9. The total dissolved solids (TDS) in groundwater indicated that the water was not suitable for human consumption, but could be used for livestock watering. Surface water electrical conductivity (EC) and inorganic nitrates was too high to be used for irrigational purposes. Nitrates in groundwater were too high to be consumed by humans. In groundwater, the total
coliform target water quality range (TWQR) was exceeded at 53% of sites analysed and faecal coliform TWQR were exceeded at 77% sites. Surface water samples complied with TWQR with regards to faecal coliforms for full contact recreational activities and livestock watering. The TWQR for E. coli, with regards to full contact recreational activities, was within a safe range for surface water. Faecal streptococci were found in 85% of groundwater sampling sites. And surface water faecal streptococci counts exceeded the TWQR for full contact recreational activities. There is no TWQR for faecal sterols in water, but concentrations of cholesterol and coprostanol was found at three of the groundwater sites analysed. This indicates faecal contamination from possible animal and human origin. Surface water samples analysed showed that the Harts River water is clean and free of faecal sterols, while the water analysed from the inflow, hotel and outflow, cholesterol eluted, which showed faecal contamination, possibly from animals. Faecal sterol markers could be detected in groundwater and surface water, adding an extra dimension to determining the quality of water systems. An optimization and sensitivity study of the method was done on waste water treatment plant (WWTP) raw sewage and effluent. The WWTP sample analysed form Potchefstroom and Carletonville WWTP yielded all six target sterols in the raw sewage water samples, but no sterols eluted in the effluent samples. The raw sewage water sample taken from the Fochville WWTP yielded all six target sterols as well, however, the effluent yielded an unknown compound as well as cholesterol. An alternative study was done where the effluent sample volume was increased. By increasing the volume of water, one can possibly increase the amount (“load”) of sterols extracted and analysed, resulting in a higher abundance of target sterols. By using the target qualifier ions of the six target sterols, and the GC-TOF/MS software, the target sterols could still be qualitatively determined. Optimal volume for raw sewage is 300 ml water sample as this is enough to yield all 6 target sterols. For optimum water quality monitoring via faecal sterol analysis of effluent and other
environmental samples, at least 1L sample volume needs to be collected and analysed. The methods described here can be applied to the analysis of environmental water samples. The technical advantages also make it suitable for routine environmental monitoring of faecal pollution. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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Relationships between infant diet, hygiene of feeding utensils and variations in the faecal bacterial floraHoult, B. January 1984 (has links)
No description available.
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A macro and micro study of the impact of sewage discharges to aquatic environments close to human habitatsNwabineli, Betty Ivie January 2000 (has links)
No description available.
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Determination of uptake of essential trace elements using stable isotopic tracers and rare earth markersUlusoy, Ulvi January 1996 (has links)
No description available.
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An analysis of the utility of quantitative faecal immunochemical tests in screening and symptomatic populationsMcdonald, Paula Jane January 2016 (has links)
Background: It has been demonstrated, in 4 large randomised control trials (RCT), that screening for colorectal cancer (CRC) using annual or biennial guaiac faecal occult blood tests (gFOBT) reduces mortality and incidence. The faecal immunochemical test (FIT) uses technology that is analytically more sensitive and specific for human haemoglobin (Hb) than gFOBT. Methods: An evaluation of the OC-Sensor Diana quantitative FIT analyser and prospective analysis of a single estimate of faecal haemoglobin concentration (f-Hb) in two clinical settings; the Scottish Bowel Screening Programme and patients referred from primary care to endoscopy services. Results: Uptake, in the cohort offered screening with FIT as a first-line test, was 4.8% higher than that seen contemporaneously in the Scottish Bowel Screening Programme. This returned to pre study levels when the study ceased and gFOBT was reintroduced. The cohort offered quantitative FIT had a positivity of 2.4% compared to 2.1% in the programme overall. Clinical outcomes, during the evaluation period, in the study cohort and the screening programme were similar. 40,125 participants returned a FIT sample device and 38,720 had their f-Hb measured. An observational study of f-Hb by sex and age, using the 97.5th percentile as a potential upper reference limit, and 90% confidence intervals (CI) showed 519 ng Hb/ml buffer (90% CI: 468 – 575) for men and 283 ng Hb/ml buffer (90% CI: 257 – 316) for women. When the data was partitioned by age quintile, f-Hb increased with age in both sexes. Quantitative FIT and endoscopy were completed by 280 patients referred from primary care for endoscopy (median age: 63 years, range: 18 to 84 years), 59.6% were female. Six (2.1%) participants had CRC, 23 (8.2%) high-risk adenoma (HRA: > 3 adenomas or any > 1 cm), 31 (11.1%) low-risk adenoma (LRA), and 26 (9.3%) inflammatory bowel disease (IBD) as the most serious diagnosis. Those with CRC had median f-Hb of > 1000 ng Hb/ml buffer. Using f-Hb with a cut-off of 50 ng Hb/ml buffer, negative predictive values of 100%, 94.4%, 93.4% and 93.9% were found for CRC, HRA, LRA and IBD. Conclusions: The introduction of quantitative FIT into population screening and symptomatic settings has the potential to optimise referral for endoscopy for those who have evidence of small amounts of bleeding, thereby improving outcomes and reducing the current burden on endoscopy services.
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The assessment of pancreatic exocrine function in childrenPuntis, J. W. L. January 1995 (has links)
No description available.
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Identification of individual koalas: microsatellite analysis of faecal DNAHey, Grace Valasi, University of Western Sydney, College of Science, Technology and Environment, School of Science, Food and Horticulture January 2003 (has links)
Current studies of koalas in the wild mainly rely on information gathered by traditional field methods, such as community sightings, spotlighting, radiotracking, animal trappings, ear tagging and faecal pellet incidence. Collection of faeces is potentially the most reliable source of non-invasively obtaining DNA samples, which can be used to identify specific individuals. This thesis demonstrated a simple, rapid and reproducible method of extracting DNA from Koala faecal pellets using a commercially available DNA extraction kit, shows the maximum age of pellets from which DNA can be reliably extracted and defines the conditions required for the long term storage of pellets before DNA extraction is carried out. Mitochondrial DNA PCR analysis provided a simple and rapid indication of the success of both the faecal DNA extraction and pellet collection process. The faecal DNA was successfully used for microsatellite analysis and the subsequent genetic profiling of individuals from within the Campbelltown Koala population. The study paves the way for the analysis of microsatellite loci in koala faecal pellet DAN to study populations, which are too sparsely distributed to allow the capture of individual koalas / Master of Science (M. Sc.) (Hons.)
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Standardisation and evaluation of differential diagnostic systems for the detection of Entamoeba histolytica and Entamoeba disparAguirre-Beltran, Aura Georgina January 1999 (has links)
Entamoeba histolytica is an invasive intestinal amoeba morphologically indistinguishable from Entamoeba dispar, a closely related organism that is not able to invade tissues. Differential diagnosis under conventional microscopy is therefore impossible. Reliable tools are needed for clinical diagnosis and for the reevaluation of the prevalence of infection with the invasive species worldwide. Monoclonal Antibody (MAb) 20/7D exhibited promising results when ascites was used to identify cultured isolates of E. histolytica by indirect immunofluorescence assays (IFA), and when used in a Faecal Antigen Capture Enzyme-Linked Immunosorbent Assay (FAC-ELISA) for laboratory diagnosis of amoebic dysentery and colitis. Here, further development of the assay was attempted to increase its sensitivity and use it for detection of asymptomatic carriers of E. histolytica. After purification and subsequent titration in ELISA, MAb 20/7D did not adequately distinguish between crude lysates of cultured E. histolytica and E. dispar trophozoites. MAb 20/7D reacted with a similar soluble antigen of E. histolytica and E. dispar, which confirmed previous observations in western blot analysis under non-reducing conditions. Therefore, the use of the FAC-ELISA for diagnosis in areas where E. dispar is endemic is probably not viable. A nucleic acid detection method was therefore developed. Polymerase Chain Reaction was used to amplify specific tandem sequences in the 24.5 Kb episome of E. histolytica and E. dispar. After PCR, internal sequences of digoxigenin-labelled PCR products were hybridized to specific biotin-labelled probes for E. histolytica or E. dispar and detected in Enzyme- Linked Immunosorbent Assay (ELISA). The Polymerase Chain Reaction Solution- Hybridisation Immunosorbent Assay (PCR-SHELA) was evaluated on samples from travellers returning from the tropics to Barcelona. The sensitivity and specificity were 98% and 100% respectively, when results were compared with microscopy. PCR-SHELA was also useful for differential diagnosis in cases of amoebic abscesses, amoebic dysentery, salmonellosis, ulcerative colitis and in asymptomatic carriage of E. histolytica. The new test gives sensitive and specific differentiation between E. histolytica and E. dispar in clinical specimens and it has proved successful in screening faecal samples in endemic areas for epidemiological purposes.
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The clinical effects of neuromodulation therapies in the treatment of faecal incontinenceThin, Noel N. K. S. January 2016 (has links)
Background and Aims Sacral nerve stimulation (SNS) is an established therapy for faecal incontinence (FI). Percutaneous tibial nerve stimulation (PTNS) is a newer, less-invasive treatment. The effectiveness, cost and acceptability of these treatments have not been systematically compared. Methods A systematic review of neuromodulation interventions for FI and an investigator-blinded, randomised pilot trial of PTNS vs. SNS including parallel quantitative (clinical outcomes and cost) and qualitative studies. Results The systematic review determined on intention-to-treat, the median success rates for SNS were 63% (range 33-66%), 58% (range 52-81%) and 54% (range 50-58%) in the short, medium and long terms respectively. The success rate for PTNS was 59% at 12 months. In the pilot trial: 40 patients (39 female; mean age 59 years) met eligibility criteria. As designed, 23 were randomised to receive SNS and 17 PTNS. 15 patients progressed to permanent SNS implantation and 16 patients received a full course of PTNS. Within group effect sizes were marginally greater for SNS than PTNS on available case analysis. FI episodes per week at baseline, 3 months and 6 months follow-up: SNS median 5.75 (IQR 5.75-15.5 ) [mean 11.4 (SD 12.0)], 2.5 (2-4.5) [4.0 (4.0)], 1.75 (1.5-5) [4.9 (6.9)], vs. PTNS median 6.5 (IQR 2.5- 16.5) [mean 10.6 (SD 11.2)], 3.5 (0.75-7.25) [5.8 (6.9)], 2.5 (0.75-10.75) [6.3 (6.9)]. At least 50% improvement in FI episodes per week at 6 months: SNS 61% vs. PTNS 47%. Effect estimates for SNS with chronic implanted stimulation were larger (67% at 6 months). Clinical FI scores and quality of life improvements complemented these results. Qualitative analysis demonstrated a very high acceptability and safety profile for both treatments. Total costs were £2,906 (SD £122) per patient for PTNS and £12,748 (SD £4,175) for SNS. Conclusions Definitive trial data between SNS or PTNS is lacking. This RCT pilot study determined that in the short-term, SNS confers a small clinical benefit over PTNS for FI but is much more expensive.
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