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Human Sources (human + source)
Selected AbstractsIdentification and typing of Malassezia yeasts using amplified fragment length polymorphism (AFLPTm), random amplified polymorphic DNA (RAPD) and denaturing gradient gel electrophoresis (DGGE)FEMS YEAST RESEARCH, Issue 2 2001Bart Theelen Abstract Three molecular tools, amplified fragment length polymorphism (AFLPTm), denaturing gradient gel electrophoresis (DGGE) and random amplified polymorphic DNA (RAPD) analysis, were explored for their usefulness to identify isolates of Malassezia yeasts. All seven species could be separated by AFLP and DGGE. Using AFLP, four genotypes could be distinguished within M. furfur. AFLP genotype 4 contained only isolates from deep human sources, and ca. 80% of these isolates were from patients with systemic disease. Most of the systemic isolates belonged to a single RAPD genotype. This suggests that systemic conditions strongly select for a particular genotype. Although the clinical use of DGGE may be limited due to technical demands, it remains a powerful tool for the analysis of complex clinical samples. [source] Hydrologic sources of carbon cycling uncertainty throughout the terrestrial,aquatic continuumGLOBAL CHANGE BIOLOGY, Issue 11 2005G. Darrel Jenerette Abstract Linking hydrologic interactions with global carbon cycling will reduce the uncertainty associated with scaling-up empirical studies and facilitate the incorporation of terrestrial,aquatic linkages within global and regional change models. Much of the uncertainty in estimates of carbon fluxes associated with precipitation and hydrologic transport results from the extensive spatial and temporal heterogeneity in both intrinsic functioning and anthropogenic modification of hydrological cycles. To better understand this variation we developed a landscape ecological approach to coupled hydrologic,carbon cycling that merges local mechanisms with multiple-scale spatial heterogeneity. This spatially explicit framework is applied to examine variability in hydrologic influences on carbon cycling along a continental scale water availability gradient with an explicit consideration of human sources of variability. Hydrologic variation is an important component of the uncertainty in carbon cycling; accounting for this variation will improve understanding of current conditions and projections of future ecosystem responses to global change. [source] Application of microbial source tracking methods in a Gulf of Mexico field settingJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2009A. Korajkic Abstract Aims:, Microbial water quality and possible human sources of faecal pollution were assessed in a Florida estuary that serves shellfishing and recreational activities. Methods and Results:, Indicator organisms (IO), including faecal coliforms, Escherichia coli and enterococci, were quantified from marine and river waters, sediments and oysters. Florida recreational water standards were infrequently exceeded (6,10% of samples); however, shellfishing standards were more frequently exceeded (28%). IO concentrations in oysters and overlaying waters were significantly correlated, but oyster and sediment IO concentrations were uncorrelated. The human-associated esp gene of Enterococcus faecium was detected in marine and fresh waters at sites with suspected human sewage contamination. Lagrangian drifters, used to determine the pathways of bacterial transport and deposition, suggested that sediment deposition from the Ochlockonee River contributes to frequent detection of esp at a Gulf of Mexico beach. Conclusions:, These data indicate that human faecal pollution affects water quality in Wakulla County and that local topography and hydrology play a role in bacterial transport and deposition. Significance and Impact of the Study:, A combination of IO enumeration, microbial source tracking methods and regional hydrological study can reliably inform regulatory agencies of IO sources, improving risk assessment and pollution mitigation in impaired waters. [source] Comparison of Campylobacter jejuni genotypes from dairy cattle and human sources from the Matamata-Piako District of New ZealandJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2008B.J. Gilpin Abstract Aims:, To identify the prevalence and types of Campylobacter jejuni carried by dairy cattle and the extent of overlap of these types with those causing disease in humans. Methods and Results:, Faecal samples from 410 dairy cattle were collected from 36 farms in the Matamata-Piako district in New Zealand. Campylobacter jejuni was isolated on all 36 farms, with a prevalence of 51% (95% CI 45,57) in dairy cattle and 65% (95% CI 58,72) in calves. Eighty-nine of these isolates were typed using Penner serotyping and pulsed field gel electrophoresis and were compared with 58 human C. jejuni isolates from people resident within this study area. Conclusions:,Campylobacter jejuni were found in the faeces of over half of the dairy cows and calves examined. Twenty-one per cent of the bovine isolates and 43% of the human isolates formed indistinguishable clusters of at least one bovine and one human isolate. Significance and Impact of the Study:, While a direct link between bovine isolates and human cases was not demonstrated, the finding of indistinguishable genotypes among C. jejuni isolates from bovine and human sources confirms that dairy cows and calves are a potential source of human campylobacteriosis. Barriers to separate bovine faecal material from the general public are therefore important public health measures. [source] The Vitamin D Status Among TibetansPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2009Gelsor Norsang UVB from the sun and intake from food are the only human sources of vitamin D. Tibet is a unique region for comparisons of these sources: (1) it lies at a low latitude and at a high altitude and has very large annual fluences of UVB; (2) the traditional Tibetan food is poor in vitamin D. Blood samples were taken from 63 persons of different age, with different occupations and staying at different places. UVB doses at these places were measured. The samples were analyzed by a standard radioimmune assay for determination of the serum concentration of 25 hydroxyvitamin D (25(OH)D). The main finding was that among nomads, there seems to be severe vitamin D deficiency (serum levels of 25(OH)D < 30 nm). We tentatively propose that the low level of 25(OH)D of nomads is related to their clothing and sun exposure habits. For persons of other occupations (students, teachers and farmers) the levels are higher, although a significant fraction of these persons also have lower levels than 75 nm, by many regarded as a limit for insufficiency related to a number of negative health conditions. The annual dose of vitamin D-generating UVB is about five times larger in Lhasa than in Oslo. Despite this, the average vitamin D status seems to be similar, except in the case of nomads. This phenomenon is certainly related to food habits. In conclusion, the 25(OH)D status among nomads in Tibet appears to be alarmingly low. However, for people of other occupations the status is more normal. [source] | ||||||||||