Taeniasis in the Bantu

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Amoebiasis: Its meaning and diagnosis

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Capillaria in man - a case report

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Rapid faecal transmission and invasive amoebiasis in Durban

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Ultraviolet photochemistry of 2-bromothiophene explored using universal ionization detection and multi-mass velocity-map imaging with a PImMS2 sensor

This project is funded by EPSRC Programme Grant No. EP/L005913/1. The raw ion events data and calculation log files can be retrieved from the University of Bristol’s research data repository and can be accessed using the following DOI:10.5523/bris.k35bi3pqsdbh2b5moo2e3puxf.The ultraviolet photochemistry of 2-bromothiophene (C4H3SBr) has been studied across the wavelength range 265-245 nm using a velocity-map imaging (VMI) apparatus recently modified for multi-mass imaging and vacuum ultraviolet (VUV, 118.2 nm) universal ionization. At all wavelengths, molecular products arising from the loss of atomic bromine were found to exhibit recoil velocities and anisotropies consistent with those reported elsewhere for the Br fragment [J. Chem. Phys. 142, 224303 (2015)]. Comparison between the momentum distributions of the Br and C4H3S fragments suggests that bromine is formed primarily in its ground (2P3/2) spin-orbit state. These distributions match well at high momentum, but relatively fewer slow moving molecular fragments were detected. This is explained by the observation of a second substantial ionic product, C3H3+. Analysis of ion images recorded simultaneously for several ion masses and the results of high-level ab initio calculations suggest that this fragment ion arises from dissociative ionization (by the VUV probe laser) of the most internally excited C4H3S fragments. This study provides an excellent benchmark for the recently modified VMI instrumentation and offers a powerful demonstration of the emerging field of multi-mass VMI using event-triggered, high frame-rate sensors, and universal ionization.Publisher PDFPeer reviewe

Influence of single nucleotide polymorphisms in COMT, MAO-A and BDNF genes on dyskinesias and levodopa use in Parkinson’s disease

Background: Clinical heterogeneity in the development of levodopa-induced dyskinesias suggests endogenous factors play a significant role in determining their overall prevalence. We hypothesised that single nucleotide polymorphisms (SNPs) in specific genes may result in a clinical phenotype conducive to an increased risk of dyskinesia. Methods: We examined the influence of SNPs in the catechol O-methyltransferase (COMT), monoamine oxidase A (MAO-A) and brain-derived neurotrophic factor (BDNF) genes on time to onset and prevalence of dyskinesias in a cohort of 285 pathologically confirmed Parkinson’s disease patients. Results: Dyskinetic patients demonstrated younger age at disease onset (60.3 years vs. 66.4 years, p<0.0001), a longer disease duration (17.0 years vs. 12.0 years, p<0.0001) and a higher maximum daily levodopa equivalent dose (LED; 926.7 mg/day vs. 617.1 mg/day, p<0.0001) than patients without dyskinesias. No individual SNP was found to influence prevalence or time to onset of dyskinesias, including after adjustment for age at disease onset, disease duration, and maximum daily LED. We observed that patients carrying alleles conferring both high COMT activity and increased MAO-A mRNA expression received significantly higher maximum and mean daily LEDs than those with low enzyme activity/mRNA expression (max LED: 835mg ± 445mg vs. 508mg ± 316mg; p=0.0056, mean LED: 601mg ± 335mg vs. 398mg ± 260mg; p=0.025). Conclusions: Individual SNPs in BDNF, COMT and MAO-A genes did not influence prevalence or time to onset of dyskinesias in this cohort. The possibility that combined COMT and MAO-A genotype is a significant factor in determining an individual’s lifetime levodopa exposure warrants further investigation

Inter-annual variability in isotope and elemental ratios recorded in otoliths of an anadromous fish

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of Geochemical Exploration 102 (2009): 181-186, doi:10.1016/j.gexplo.2008.10.001.Isotope ratios and elemental concentrations in otoliths are often used as natural tags to reconstruct migratory movements and connectivity patterns in marine and anadromous fishes. Although differences in otolith geochemistry have been documented among geographically separated populations, inter-annual variation within locations is less frequently examined. We compared otolith isotope (δ18O and 87Sr:86Sr) and elemental ratios (Sr:Ca and Ba:Ca) from several annual cohorts of juvenile American shad (Alosa sapidissima) in three rivers. These four geochemical signatures distinguished among river-specific populations of this species at both large and small geographic scales, with δ18O and 87Sr:86Sr generating the majority of multivariate variation. We found significant variation among years for all variables in two to three rivers. However, the magnitude of variability differed among ratios, with δ18O ratios showing substantial inter-annual shifts while 87Sr:86Sr ratios were relatively stable across years. Sr:Ca and Ba:Ca ratios also varied among years. These results imply that investigators using environmentally labile signatures must quantify geochemical signatures for each cohort of interest in order to confidently identify origins of migrants.Funding was provided by National Science Foundation grants to SRT (OCE-0215905 and OCE-0134998) and grants by the American Museum of Natural History Lerner-Gray Fund for Marine Research, SEASPACE, Inc., and the WHOI Ocean Life Institute to BDW

Deletion at ITPR1 Underlies Ataxia in Mice and Spinocerebellar Ataxia 15 in Humans

We observed a severe autosomal recessive movement disorder in mice used within our laboratory. We pursued a series of experiments to define the genetic lesion underlying this disorder and to identify a cognate disease in humans with mutation at the same locus. Through linkage and sequence analysis we show here that this disorder is caused by a homozygous in-frame 18-bp deletion in Itpr1 (Itpr1Δ18/Δ18), encoding inositol 1,4,5-triphosphate receptor 1. A previously reported spontaneous Itpr1 mutation in mice causes a phenotype identical to that observed here. In both models in-frame deletion within Itpr1 leads to a decrease in the normally high level of Itpr1 expression in cerebellar Purkinje cells. Spinocerebellar ataxia 15 (SCA15), a human autosomal dominant disorder, maps to the genomic region containing ITPR1; however, to date no causal mutations had been identified. Because ataxia is a prominent feature in Itpr1 mutant mice, we performed a series of experiments to test the hypothesis that mutation at ITPR1 may be the cause of SCA15. We show here that heterozygous deletion of the 5′ part of the ITPR1 gene, encompassing exons 1–10, 1–40, and 1–44 in three studied families, underlies SCA15 in humans

Nutrients increase epiphyte loads: broad-scale observations and an experimental assessment

The original publication can be found at www.springerlink.comThere is a global trend towards elevated nutrients in coastal waters, especially on human-dominated coasts. We assessed local- to regional-scale relationships between the abundance of epiphytic algae on kelp ( Ecklonia radiata) and nutrient concentrations across much of the temperate coast of Australia, thus assessing the spatial scales over which nutrients may affect benthic assemblages. We tested the hypotheses that (1) percentage cover of epiphytic algae would be greater in areas with higher water nutrient concentrations, and (2) that an experimental enhancement of nutrient concentrations on an oligotrophic coast, to match more eutrophic coasts, would cause an increase in percentage cover of epiphytic algae to match those in more nutrient rich waters. Percentage cover of epiphytes was most extensive around the coast of Sydney, the study location with the greatest concentration of coastal chlorophyll a (a proxy for water nutrient concentration). Elevation of nitrate concentrations at a South Australian location caused an increase in percentage cover of epiphytes that was comparable to percentage covers observed around Sydney’s coastline. This result was achieved despite our inability to match nutrient concentrations observed around Sydney (<5% of Sydney concentrations), suggesting that increases to nutrient concentrations may have disproportionately larger effects in oligotrophic waters.Bayden D. Russell, Travis S. Elsdon Bronwyn M. Gillanders and Sean D. Connel