The Effect of Egg Embryonation on Field-Use of a Hookworm Benzimidazole-Sensitivity Egg Hatch Assay in Yunnan Province, People's Republic of China

With the implementation of mass drug administration programmes for the control of human soil transmitted helminths there is a need to develop drug sensitivity monitoring tools to detect the emergence of resistance. The present study aimed to use an egg hatch assay to measure benzimidazole sensitivity in human hookworms in a field setting in Yunnan province, People's Republic of China, in order to assess whether the assay offered a practical means of monitoring drug sensitivity in human hookworms in such a location. The assay proved able to generate dose response data, which allowed for the drug sensitivity of the hookworms in the local children to be described; the mean IC50 was 0.10 ug/ml thiabendazole. The study also found that practical issues associated with stool collection procedures, specifically the embryonation of some eggs during the time elapsing between stool deposition and egg recovery, can have an impact on the drug sensitivity data. We suggest means for data analysis that overcome the impact of egg embryonation on drug dose response data, which should allow for the use of such assays at different field sites worldwide

Exploring the anthelmintic properties of Australian native shrubs with respect to their potential role in livestock grazing systems

We measured in vitro anthelmintic activity in extracts from 85 species of Australian native shrub, with a view to identifying species able to provide a degree of worm control in grazing systems. Approximately 40% of the species showed significant activity in inhibiting development of Haemonchus contortus larvae. The most active extracts showed IC50 values of 60–300 mg/ml. Pre-incubation with polyvinylpolypyrrolidine removed the activity from some extracts, implicating tannins as the bioactive agent, while in other cases the pre-incubation had no effect, indicating the presence of other anthelmintic compounds. Plant reproductive maturity (onset of flowering or fruiting) was associated with increasing anthelmintic activity in some species. Variability was observed between plants of the same species growing in different environments, while variation between individual plants of the same species within a single field suggests the existence of distinct chemotypes. Significant activity against adult H. contortus worms in vitro was also demonstrated in a limited number of extracts tested against this life stage. Our study indicates that there is potential for Australian native shrubs to play an anthelmintic role in grazing systems, and highlights some plant biology factors which will need to be considered in order to maximize any anthelmintic effects.A. C. Kotze, J. O’Grady, J. Emms, A. F. Toovey, S. Hughes, P. Jessop, M. Bennell P. E. Vercoe and D. K. Revel

The effects of trampling on assemblages of ground beetles (Coleoptera, Carabidae) in urban forests in Helsinki, Finland

The occurrence of carabid beetles in relation to trampling was examined in urban forest sites located in the city of Helsinki, southern Finland. The degree of wear of the forest floor was assessed and used as a measure of trampling intensity. In particular, we examined the following predictions: (1) carabid diversity should decrease with increasing trampling intensity, (2) mean body size of the dominating carabid species should decrease with increasing trampling intensity, and (3) opportunistic species should gain dominance in severely trampled sites. In total, 1,326 beetles representing 27 species were captured. The first prediction was not supported, as there was no correlation between species richness or Hill’s N2 diversity index and trampling intensity. However, there was a positive correlation between number of carabids captured and trampling intensity of the site. The second hypothesis gained some support, as there was a marginally significant negative correlation between body size and trampling intensity. The hypothesis that opportunistic species should gain dominance in severely trampled sites was supported as one species was very dominant (Pterostichus melanarius, 60.0%) in the heavily trampled sites, while there were two equally and less dominant species in the less trampled sites. Individual species did show different responses to the effects of trampling, and the most sensitive forest species may not survive in the heavily trampled sites.We conclude that at the community level (e.g., species richness, diversity), the effects of trampling on carabids in urban forests are subtle, but impacts are pronounced for some sensitive species

Familial defective apolipoprotein-B is rare in hypercholesterolaemic South African Afrikaners, coloureds and Indians

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A Novel High Throughput Assay for Anthelmintic Drug Screening and Resistance Diagnosis by Real-Time Monitoring of Parasite Motility

Parasitic worms cause untold morbidity and mortality on billions of people and livestock. Drugs are available but resistance is problematic in livestock parasites and is a looming threat for human helminths. Currently, new drug discovery and resistance monitoring is hindered as drug efficacy is assessed by observing motility or development of parasites using laborious, subjective, low-throughput methods evaluated by eye using microscopy. Here we describe a novel application for a cell monitoring device (xCELLigence) that can simply and objectively assess real time anti-parasite efficacy of drugs on eggs, larvae and adults in a fully automated, label-free, high-throughput fashion. This technique overcomes the current low-throughput bottleneck in anthelmintic drug development and resistance detection pipelines. The widespread use of this device to screen for new therapeutics or emerging drug resistance will be an invaluable asset in the fight against human, animal and plant parasitic helminths and other pathogens that plague our planet

Prediction of Wetland Hydrogeomorphic Type Using Morphometrics and Landscape Characteristics

Accurate spatial maps of wetlands are critical for regional conservation and rehabilitation assessments, yet this often remains an elusive target. Such maps ideally provide information on wetland occurrence and extent, hydrogeomorphic (HGM) type, and ecological condition/level of degradation. All three elements are needed to provide ancillary layers to support mapping from remote imagery and ground-truthing. Knowledge of HGM types is particularly important, because different types show different levels of sensitivity to degradation, and modeling accuracy for occurrence. Here, we develop and test a simple approach for predicting the most likely HGM type for mapped yet unattributed wetland polygons. We used a dataset of some 11,500 wetland polygons attributed by HGM types (floodplain, depression, seep, channeled, and un-channeled valley-bottom) from the Western Cape Province in South Africa. Polygons were attributed and described in terms of nine landscape metrics, at a sub-catchment scale. Using a combination of box-and-whisker plots and PCA, we identified four variables (groundwater depth, relief ratio, slope, and elevation) as being the most important variables in differentiating HGM types. We divided the data into equal parts for training and testing of a simple Bayesian network model. Model validation included field assessments. HGM types were most sensitive to elevation. Model predication was good, with error rates of only 32%. We conclude that this is a useful technique that can be widely applied using readily available data, for rapid classification of HGM types at a regional scale. © Copyright © 2020 Rivers-Moore, Kotze, Job and Mohanlal

The Genetic Structure and History of Africans and African Americans.

Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observed high levels of mixed ancestry in most populations, reflecting historical migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (approximately 71%), European (approximately 13%), and other African (approximately 8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies

Fisher Matrix Preloaded -- Fisher4Cast

The Fisher Matrix is the backbone of modern cosmological forecasting. We describe the Fisher4Cast software: a general-purpose, easy-to-use, Fisher Matrix framework. It is open source, rigorously designed and tested and includes a Graphical User Interface (GUI) with automated LATEX file creation capability and point-and-click Fisher ellipse generation. Fisher4Cast was designed for ease of extension and, although written in Matlab, is easily portable to open-source alternatives such as Octave and Scilab. Here we use Fisher4Cast to present new 3-D and 4-D visualisations of the forecasting landscape and to investigate the effects of growth and curvature on future cosmological surveys. Early releases have been available at http://www.cosmology.org.za since May 2008 with 750 downloads in the first year. Version 2.2 is made public with this paper and includes a Quick Start guide and the code used to produce the figures in this paper, in the hope that it will be useful to the cosmology and wider scientific communities.Comment: 30 Pages, 15 figures. Minor revisions to match published version, with some additional functionality described to match the current version (2.2) of the code. Software available at http://www.cosmology.org.za. Usage, structure and flow of the software, as well as tests performed are described in the accompanying Users' Manua