83 research outputs found
A comparison of mollusc diversity between the relatively pristine Marico River and the impacted Crocodile River, two major tributaries of the Limpopo River, South Africa
A study of the freshwater mollusc diversity was conducted at selected sites in the relatively pristine Marico River and the impacted Crocodile River, the major tributaries of the Limpopo River. Four surveys were conducted, two in an early (May 2013 and 2014) and two in a late (November 2013 and 2014) low-flow period. Semi-quantitative surveys were done by sampling the vegetation, as well as the substratum, with a standard SASS net for approximately 15 min each. Environmental parameters including water temperature, electrical conductivity (EC) and pH were measured at each site. Molluscs were identified up to species level, sorted, counted, and the presence of juvenile specimens recorded. Historical data for the 1/16th degree square grids (loci), in which each of the sampling sites of the current study was located, were extracted from the National Freshwater Snail Collection at the Unit for Environmental Sciences and Management, Potchefstroom Campus of the North-West University. During this study, 20 and 9 species were recovered from the Marico and Crocodile Rivers, respectively, as compared to 13 and 12 species on record for these loci, respectively. Juvenile specimens were present during the four surveys at most of the sites. Canonical correspondence analyses were applied which revealed that biotopes, water temperature and EC played the most significant role in the distribution and abundance of species. The relatively high mollusc diversity and the fact that juveniles were present throughout the study, demonstrated that current habitat and environmental conditions were suitable to promote recruitment and the sustainability of diverse mollusc populations in the Marico River and its tributaries. However, in contrast to this, the exploitation of and habitat transformation in the Crocodile River has resulted in the decrease of biotopes which eventually could have led to the decrease in diversity and the establishment of P. acuta, an exotic invader species.Keywords: freshwater molluscs, biodiversity, Marico River, Crocodile River, environmental variable
Outcomes of laboratory-confirmed SARS-CoV-2 infection during resurgence driven by Omicron lineages BA.4 and BA.5 compared with previous waves in the Western Cape Province, South Africa
OBJECTIVE: We aimed to compare clinical severity of Omicron BA.4/BA.5 infection with BA.1 and earlier variant infections among laboratory-confirmed SARS-CoV-2 cases in the Western Cape, South Africa, using timing of infection to infer the lineage/variant causing infection. METHODS: We included public sector patients aged ≥20 years with laboratory-confirmed COVID-19 between 1-21 May 2022 (BA.4/BA.5 wave) and equivalent prior wave periods. We compared the risk between waves of (i) death and (ii) severe hospitalization/death (all within 21 days of diagnosis) using Cox regression adjusted for demographics, comorbidities, admission pressure, vaccination and prior infection. RESULTS: Among 3,793 patients from the BA.4/BA.5 wave and 190,836 patients from previous waves the risk of severe hospitalization/death was similar in the BA.4/BA.5 and BA.1 waves (adjusted hazard ratio (aHR) 1.12; 95% confidence interval (CI) 0.93; 1.34). Both Omicron waves had lower risk of severe outcomes than previous waves. Prior infection (aHR 0.29, 95% CI 0.24; 0.36) and vaccination (aHR 0.17; 95% CI 0.07; 0.40 for at least 3 doses vs. no vaccine) were protective. CONCLUSION: Disease severity was similar amongst diagnosed COVID-19 cases in the BA.4/BA.5 and BA.1 periods in the context of growing immunity against SARS-CoV-2 due to prior infection and vaccination, both of which were strongly protective
The prevalence of nutritional anemia in pregnancy in an east Anatolian province, Turkey
<p>Abstract</p> <p>Background</p> <p>Anemia is considered a severe public health problem by World Health Organization when anemia prevalence is equal to or greater than 40% in the population. The purpose of this study was to determine the anemia prevalence with the associated factors in pregnant women and to determine the serum iron, folate and B12 vitamin status in anaemic pregnants in Malatya province.</p> <p>Methods</p> <p>This is a cross-sectional survey. A multi-sage stratified probability-proportional-to-size cluster sampling methodology was used. A total of 823 pregnant women from sixty clusters were studied. Women were administered a questionnaire related with the subject and blood samples were drawn. Total blood count was performed within four hours and serum iron, folate and B12 vitamin were studied after storing sera at -20 C for six months.</p> <p>Results</p> <p>Anemia prevalence was 27.1% (Hb < 11.0 gr/dl). Having four or more living children (OR = 2.2), being at the third trimester (OR = 2.3) and having a low family income (OR = 1.6) were determined as the independent predictors of anemia in pregnancy. Anemia was also associated with soil eating (PICA) in the univariate analysis (p < 0.05). Of anaemic women, 50.0% had a transferrin saturation less than 10% indicating iron deficiency, 34.5% were deficient in B12 vitamin and 71.7% were deficient in folate. Most of the anemias were normocytic-normochromic (56.5%) indicating mixed anemia.</p> <p>Conclusions</p> <p>In Malatya, for pregnant women anemia was a moderate public health problem. Coexisting of iron, folate and B vitamin deficiencies was observed among anaemics. To continue anemia control strategies with reasonable care and diligence was recommended.</p
The influence of different helminth infection phenotypes on immune responses against HIV in co-infected adults in South Africa
<p>Abstract</p> <p>Background</p> <p>The convergent distribution of the Human Immunodeficiency Virus (HIV) and helminth infections has led to the suggestion that infection with helminths exacerbates the HIV epidemic in developing countries. In South Africa, it is estimated that 57% of the population lives in poverty and carries the highest burden of both HIV and helmith infections, however, the disease interactions are under-researched.</p> <p>Methods</p> <p>We employed both coproscopy and <it>Ascaris lumbricoides</it>-specific serum IgE to increase diagnostic sensitivity and to distinguish between different helminth infection phenotypes and their effects on immune responses in HIV co-infected individuals. Coproscopy was done by formol ether and Kato Katz methods. HIV positive and negative adults were stratified according to the presence or absence of <it>A. lumbricoides </it>and/or <it>Trichuris trichuria </it>eggs with or without elevated <it>Ascaris </it>IgE. Lymphocyte subsets were phenotyped by flow cytometry. Viral loads, serum total IgE and eosinophils were also analysed. Lymphocyte activation markers (CCR5, HLA-DR, CD25, CD38 and CD71) were determined. Non parametric statistics were used to describe differences in the variables between the subgroups.</p> <p>Results</p> <p>Helminth prevalence ranged between 40%-60%. Four distinct subgroups of were identified, and this included egg positive/high <it>Ascaris</it>-specific IgE (egg<sup>+</sup>IgE<sup>hi</sup>), egg positive/low IgE (egg<sup>+</sup>IgE<sup>lo</sup>), egg negative/high IgE (egg<sup>-</sup>IgE<sup>hi</sup>) and egg negative/low IgE (egg<sup>-</sup>IgE<sup>lo</sup>) individuals. The egg<sup>+</sup>IgE<sup>hi </sup>subgroup displayed lymphocytopenia, eosinophilia, (low CD4<sup>+ </sup>counts in HIV<sup>- </sup>group), high viral load (in HIV<sup>+ </sup>group), and an activated lymphocyte profile. High <it>Ascaris </it>IgE subgroups (egg<sup>+</sup>IgE<sup>hi </sup>and egg<sup>-</sup>IgE<sup>hi</sup>) had eosinophilia, highest viral loads, and lower CD4<sup>+ </sup>counts in the HIV<sup>- </sup>group). Egg excretion and low IgE (egg<sup>+</sup>IgE<sup>lo</sup>) status demonstrated a modified Th<sub>2 </sub>immune profile with a relatively competent response to HIV.</p> <p>Conclusions</p> <p>People with both helminth egg excretion and high <it>Ascaris</it>-IgE levels had dysregulated immune cells, high viral loads with more immune activation. A modified Th<sub>2 </sub>helminth response in individuals with egg positive stools and low <it>Ascaris </it>IgE showed a better HIV related immune profile. Future research on helminth-HIV co-infection should include parasite-specific IgE measurements in addition to coproscopy to delineate the different response phenotypes. Helminth infection affects the immune response to HIV in some individuals with high IgE and egg excretion in stool.</p
Estimating the burden of disease attributable to four selected environmental risk factors in South Africa
The first South African National Burden of Disease study quantified the underlying causes of premature mortality and morbidity experienced in South Africa in the year 2000. This was followed by a Comparative Risk Assessment to estimate the contributions of 17 selected risk factors to burden of disease in South Africa. This paper describes the health impact of exposure to four selected environmental risk factors: unsafe water, sanitation and hygiene; indoor air pollution from household use of solid fuels; urban outdoor air pollution and lead exposure.The study followed World Health Organization comparative risk assessment methodology. Population-attributable fractions were calculated and applied to revised burden of disease estimates (deaths and disability adjusted life years, [DALYs]) from the South African Burden of Disease study to obtain the attributable burden for each selected risk factor. The burden attributable to the joint effect of the four environmental risk factors was also estimated taking into account competing risks and common pathways. Monte Carlo simulation-modeling techniques were used to quantify sampling, uncertainty.Almost 24 000 deaths were attributable to the joint effect of these four environmental risk factors, accounting for 4.6% (95% uncertainty interval 3.8-5.3%) of all deaths in South Africa in 2000. Overall the burden due to these environmental risks was equivalent to 3.7% (95% uncertainty interval 3.4-4.0%) of the total disease burden for South Africa, with unsafe water sanitation and hygiene the main contributor to joint burden. The joint attributable burden was especially high in children under 5 years of age, accounting for 10.8% of total deaths in this age group and 9.7% of burden of disease.This study highlights the public health impact of exposure to environmental risks and the significant burden of preventable disease attributable to exposure to these four major environmental risk factors in South Africa. Evidence-based policies and programs must be developed and implemented to address these risk factors at individual, household, and community levels
The use of financial management practices by small, medium and micro enterprises: a perspective from South Africa
This paper reports on an investigation of financial management practices used by small, medium-sized and micro-enterprises (SMMEs) in South Africa. It was found that more than half the SMMEs examined use external accounting staff to prepare accounting reports and more than 60% rely on external accounting staff to interpret and use accounting information. A majority of the SMME owners were found to lack interpretation skills and an awareness of how to use information from financial statements. An implication of this study therefore is that policy makers, business support organizations, banks and academic institutions need to focus on educating SMMEs more effectively in financial management, thereby mitigating the risk of cash flow problems and business failure
Multidimensional characterization of global food supply from 1961 to 2013
Food systems are increasingly globalized and interdependent, and diets around the world are changing. Characterization of national food supplies and how they have changed can inform food policies that ensure national food security, support access to healthy diets and enhance environmental sustainability. Here we analysed data for 171 countries on the availability of 18 food groups from the United Nations Food and Agriculture Organization to identify and track multidimensional food supply patterns from 1961 to 2013. Four predominant food-group combinations were identified that explained almost 90% of the cross-country variance in food supply: animal source and sugar, vegetable, starchy root and fruit, and seafood and oilcrops. South Korea, China and Taiwan experienced the largest changes in food supply over the past five decades, with animal source foods and sugar, vegetables and seafood and oilcrops all becoming more abundant components of the food supply. In contrast, in many Western countries the supply of animal source foods and sugar declined. Meanwhile, there was remarkably little change in the food supply in countries in the sub-Saharan Africa region. These changes led to a partial global convergence in the national supply of animal source foods and sugar, and a divergence in those of vegetables and of seafood and oilcrops. Our analysis generated a novel characterization of food supply that highlights the interdependence of multiple food types in national food systems. A better understanding of how these patterns have evolved and will continue to change is needed to support the delivery of healthy and sustainable food system policies
Antimitotic drugs in the treatment of cancer
Cancer is a complex disease since it is adaptive
in such a way that it can promote proliferation and
invasion by means of an overactive cell cycle and in turn
cellular division which is targeted by antimitotic drugs
that are highly validated chemotherapy agents. However,
antimitotic drug cytotoxicity to non-tumorigenic cells and
multiple cancer resistance developed in response to drugs
such as taxanes and vinca alkaloids are obstacles faced in
both the clinical and basic research field to date. In this
review, the classes of antimitotic compounds, their mechanisms
of action and cancer cell resistance to chemotherapy
and other limitations of current antimitotic compounds are
highlighted, as well as the potential of novel 17-β estradiol
analogs as cancer treatment.Medical Research Council of South Africa, the Research Committee of the Faculty of Health Sciences of the University of Pretoria, the Cancer association of South Africa and the National Research Foundation.http://link.springer.com/journal/280hb201
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