The influence of low versus high fibre haylage diets in combination with training or pasture rest on equine gastric ulceration syndrome (EGUS)

The aim of this field study was to examine the influence of a low fibre (LF) and a high fibre (HF) diet on the presence of gastric ulceration in thirty 3-year old Dutch Warmblood horses during training period and during pasture rest. In the first part of the study all horses were stabled individually and fed either an iso-energetic HF (75% haylage) or LF (25% haylage) diet for sixteen weeks. Horses were exercised daily throughout this period, after which the first gastroscopy was performed. The second gastroscopy for all horses was performed following a fourteen week Pasture period during which grass was supplemented with haylage. Contrary to expectations the scores for number and severity of gastric lesions during the Training period were significantly higher in the HF group compared to the LF group. Additionally, horses of the HF group showed high haylage retention in the stomach after 12 hours fasting, whilst the LF group exhibited marked bedding eating and coprophagia. The results of gastroscopy following the Pasture period with extra haylage feeding for all horses, were similar to the HF horses following the Training period. These unexpected results may be related to the retention of the pre-fermented feed (haylage) in the stomach leading to continuing fermentation with increased volatile fatty acid (VFA) production in the stomach. The consumption of bedding and coprophagy shown by the LF group may have limited the previously reported high risk of gastric ulceration on a lowfibre diet

Response-related potentials during semantic priming: the effect of a speeded button response task on ERPs

This study examines the influence of a button response task on the event-related potential (ERP) in a semantic priming experiment. Of particular interest is the N400 component. In many semantic priming studies, subjects are asked to respond to a stimulus as fast and accurately as possible by pressing a button. Response time (RT) is recorded in parallel with an electroencephalogram (EEG) for ERP analysis. In this case, the response occurs in the time window used for ERP analysis and response-related components may overlap with stimulus-locked ones such as the N400. This has led to a recommendation against such a design, although the issue has not been explored in depth. Since studies keep being published that disregard this issue, a more detailed examination of influence of response-related potentials on the ERP is needed. Two experiments were performed in which subjects pressed one of two buttons with their dominant hand in response to word-pairs with varying association strength (AS), indicating a personal judgement of association between the two words. In the first experiment, subjects were instructed to respond as fast and accurately as possible. In the second experiment, subjects delayed their button response to enforce a one second interval between the onset of the target word and the button response. Results show that in the first experiment a P3 component and motor-related potentials (MRPs) overlap with the N400 component, which can cause a misinterpretation of the latter. In order to study the N400 component, the button response should be delayed to avoid contamination of the ERP with response-related components

The essence of fertilization: oocyte meets sperm

The problem of reduced fertility in high yielding dairy cattle is a very complicated one, and the relationship between various measures of fertility and level of milk production remains controversial. In this brief review the essence of the problem is considered: what is the oocyte's and the sperm's contribution, and what is the importance of the resulting embryo in the declining fertility of the Holstein Friesian cow

Caenorhabditis elegans as a model system for studying drug induced mitochondrial toxicity

Today HIV-1 infection is recognized as a chronic disease with obligatory lifelong treatment to keep viral titers below detectable levels. The continuous intake of antiretroviral drugs however, leads to severe and even life-threatening side effects, supposedly by the deleterious impact of nucleoside-analogue type compounds on the functioning of the mitochondrial DNA polymerase. For detailed investigation of the yet partially understood underlying mechanisms, the availability of a versatile model system is crucial. We therefore set out to develop the use of Caenorhabditis elegansto study drug induced mitochondrial toxicity. Using a combination of molecular-biological and functional assays, combined with a quantitative analysis of mitochondrial network morphology, we conclude that anti-retroviral drugs with similar working mechanisms can be classified into distinct groups based on their effects on mitochondrial morphology and biochemistry. Additionally we show that mitochondrial toxicity of antiretroviral drugs cannot be exclusively attributed to interference with the mitochondrial DNA polymerase

A reflection on professional development of registrars completing a module in Health Care Practice

Background. A need for professional development in the training of registrars was identified by the School of Medicine, University of the Free State (UFS), Bloemfontein, South Africa, in 2007.Objective. To develop the module on Health Care Practice (HCP) (GPV703) to address these shortcomings.Methods. A quantitative study, enhanced by qualitative data, was conducted. A self-administered questionnaire that included a rating scale and open-ended questions was used. The quantitative responses were analysed using Microsoft Excel, and the qualitative data were edited, categorised and summarised.Results. The questionnaire was completed by 95% (n=38/40) of registrars. The quantitative questions, regarding the orientation session, content and applicability of the content of the module, showed satisfactory to very good responses. Of the 40 surveys collected from registrars, 77.5% (n=31/40) were completed by heads of department (HODs). The surveys showed a significant improvement in registrar competence: 17 were given an aboveaverage rating and 14 an average rating; there were no below-average ratings.Discussion. The module on HCP, which is part of the MMed programme, addressed aspects required by registrars to develop and/or enhance their skills, knowledge and professional behaviour with regard to ethics, practice management and patient communication. Registrars were generally satisfied with the content and presentation of the module. The open-ended questions raised concerns about aspects of patient communication and electronic learning. These need to be addressed to improve the quality of the module.Conclusion. The module on HCP (GPV703), as implemented by the UFS, is successful in addressing key aspects often neglected because of the strong clinical focus of a medical programme

Baculovirus PTP2 Functions as a Pro-Apoptotic Protein.

This is the final version. Available from MDPI via the DOI in this record.The family Baculoviridae encompasses a large number of invertebrate viruses, mainly infecting caterpillars of the order Lepidoptera. The baculovirus Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) induces physiological and behavioral changes in its host Spodoptera exigua, as well as immunological responses, which may affect virus transmission. Here we show that the SeMNPV-encoded protein tyrosine phosphatase 2 (PTP2) induces mild apoptosis in Spodoptera frugiperda (Sf) 21 cells upon transient expression. Transient expression of a catalytic-site mutant of ptp2 did not lead to apoptosis, indicating that the phosphatase activity of PTP2 is needed to induce apoptosis. We also found that the caspase level (indicator of apoptosis) was higher in cells transfected with the ptp2 gene than in cells transfected with the catalytic mutant. Adding a caspase inhibitor reduced the level of ptp2-induced apoptosis. Moreover, deletion of the ptp2 gene from the viral genome prevented the induction of apoptosis in S. exigua hemocytes. The virus titer and virulence indices (the viral infectivity and the time to death) were not affected by deletion of the ptp2 gene. However, the viral occlusion body yield from S. exigua larvae infected with the mutant virus lacking the ptp2 gene was much lower than the yield from larvae infected with the wild-type (WT) virus. We hypothesize that the observed pro-apoptotic effects of PTP2 are the result of PTP2-mediated immune suppression in larvae, which consequently leads to higher viral occlusion body yields

Evaluation of point-of-care tests for detecting microalbuminuria in diabetic patients

Background: Microalbuminuria, the presence of low levels of albumin in the urine, indicates renal damage and is recognised as a risk factor for the progression of renal and cardiovascular disease. Several international scientific bodies recommend microalbuminuria screening. Point-of-care testing (POCT) of microalbuminuria allows immediate identification of risk, and monitoring of treatment effects. In this study, two POCT instruments were evaluated as microalbuminuria screening methods. Method: Spot urine specimens from diabetic patients were analysed with the quantitative HemoCue® urine albumin analyser (n = 245), and the semiquantitative Clinitek® microalbumin urine dipstick (n = 204). These results were compared to the respective data for laboratory-determined albumin (nephelometry), creatinine (modified Jaffe) and albumin-to-creatinine ratio (ACR). Results: Linear regression analysis demonstrated a good correlation for the HemoCue® urine albumin with the laboratorydetermined albumin concentration (y = 0.8557x + 0.2487y, r = 0.97). The sensitivities for the HemoCue® and Clinitek® POCT systems were 79.6% and 83.8%, and the specificities 97.1% and 93.8% respectively. Positive and negative predictive values for the HemoCue® were 95.6% and 85.8%, and were 88.6% and 91.0% the Clinitek®. The repeatability of both instruments was excellent. Both instruments are easy to use, and more cost-effective than the laboratory methods for albumin and ACR. Conclusion: Both the HemoCue® and the Clinitek® microalbumin POCT systems for albuminuria are easy to use and inexpensive, and are adequately accurate as a screening method. Although the HemoCue® POCT system measures only urine albumin concentration, its sensitivity and specificity compared well with that of the Clinitek® POCT system, which determines the ACR.Keywords: microalbuminuria, point-of-care testing, HemoCue®, Clinitek®, urinary albumin excretio

Short Communication: Conductivity as an indicator of surface water quality in the proximity of ferrochrome smelters in South Africa

South Africa is one of the leading ferrochrome (FeCr) producing countries. One of the main environmental and healthrelated issues associated with FeCr production is the possible generation of Cr(VI). However,  Cr(VI) is not the only potential pollutant that has to be considered during FeCr production. Various water- soluble species are present in FeCr waste materials and in process water. Considering the size of the  South African FeCr industry and its global importance, it is essential to assess the extent of potential surface water pollution in the proximity of FeCr smelters by such watersoluble species. In this study  water conductivity was measured as a proxy of general water quality. Although deposition was not  measured, comparison of surface water results indicated that atmospheric deposition of pollutants  originating from FeCr smelting did not significantly impact surface water quality, but that surface run-off  and/or groundwater leaching were the main contributors. At two FeCr smelters it was observed that these smelters did not impact surface water quality negatively. In contrast, surface water pollution originating from at least four FeCr smelters was apparent. However, only at one smelter did pollution result in surface water conductivity that indicated a water quality not fit for human consumption. No correlations could be made between potable water quality and possible pollution from FeCr smelters.  Not with standing this limitation, it was found that potable water sampled at all sites complied with the conductivity criteria for human consumption.Keywords: surface water, ferrochromium, South Africa, conductivity, elemental composition of total dissolved solids (TDS), potable wate

A survey of Cr(VI) contamination of surface water in the proximity of ferrochromium smelters in South Africa

South Africa holds approximately three-quarters of the world’s viable chromite ore reserves and is one of the largest ferrochrome producers. It is impossible to completely exclude oxygen from all high-temperature ferrochrome production steps, which results in the unintentional possibility of generating small amounts of Cr(VI) species that are generally considered as carcinogenic. In this study, Cr(VI) levels present in surface water within the vicinity of ferrochrome smelters located in the Bushveld Igneous Complex were monitored for a period of 1 year. The results indicated that surface water in the proximity of ferrochrome smelters was mostly unaffected by Cr(VI) pollution. Two surface water sampling sites were consistently impacted by relatively low level Cr(VI) pollution (annual mean values of 4.4 and 6.3 μg/ℓ, respectively), with no values in excess of the 50 μg/ℓ drinking water limit recorded. However, at two other surface water sampling sites, maximum Cr(VI) concentrations of 198 and 220 μg/ℓ were measured. The median Cr(VI) concentrations for these two sites were 1.8 and 1.9 μg/ℓ, respectively, indicating that Cr(VI) pollution of the surface water at these sites was erratic and most likely due to surface run-off. Although drinking water pollution was not the main focus of this paper, results indicated that drinking water in the proximity of most FeCr smelters was not polluted by Cr(VI). However, the annual mean Cr(VI) concentration of drinking water that originated from a borehole at one drinking water sampling site was 45.3 μg/ℓ, with several months exceeding the 50 μg/ℓ limit. Significant steps have, however, already been taken to remedy the situation.Keywords: Cr(VI); hexavalent chromium; surface water; drinking water; South Africa; ferrochromium industr

The International Mass Loading Service

The International Mass Loading Service computes four loadings: a) atmospheric pressure loading; b) land water storage loading; c) oceanic tidal loading; and d) non-tidal oceanic loading. The service provides to users the mass loading time series in three forms: 1) pre-computed time series for a list of 849 space geodesy stations; 2) pre-computed time series on the global 1deg x 1deg grid; and 3) on-demand Internet service for a list of stations and a time range specified by the user. The loading displacements are provided for the time period from 1979.01.01 through present, updated on an hourly basis, and have latencies 8-20 hours.Comment: 8 pages, 3 figures, to appear in the Proceedings of the Reference Frames for Applications in Geosciences Simposium, held in Luxemboug in October 201