risk-factor profile for chronic lifestyle diseases in three rural Free State towns

Background: Chronic diseases of lifestyle account for millions of deaths each year globally. These diseases share similar modifiable risk factors, including hypertension, tobacco smoking, diabetes, obesity,  hyperlipidaemia and physical inactivity. In South Africa the burden of noncommunicable disease risk factors is high. To reduce or control as many lifestyle risk factors as possible in a population, the distinct risk-factor profile for that specific community must be identified. Therefore, the aim of this study was to assess the health status in three rural Free State communities and to identify a distinct risk-factor profile for chronic lifestyle diseases in these communities.Methods: This study forms part of the baseline phase of the Assuring Health for All in the Free State project, which is a prospective and longitudinal epidemiological study aimed at determining how living in a rural area can either protect or predispose one to developing chronic lifestyle diseases. The communities of three black and coloured, rural Free State areas, namely Trompsburg, Philippolis and Springfontein, were evaluated. The study population consisted of 499 households, and 658 individuals (including children) participated in the study. Only results of adult participants between 25 and 64 years will be reported in this article. The study group consisted of 29.4% male and 70.6% female participants, with a mean age of 49 years. During interviews with trained researchers, household socio-demographic questionnaires, as well as individual  questionnaires evaluating diet, risk factors (history of hypertension and/or diabetes) and habits (tobacco smoking and physical activity levels), were completed. All participants underwent anthropometric evaluation, medical examination and blood sampling to determine fasting blood glucose levels.Results: Multiple risk factors for noncommunicable diseases were identified in this study population, including high blood pressure, tobacco smoking,high body mass index (BMI), diabetes and physical inactivity. The reported risk-factor profile was ranked. Increased waist circumference was rankedhighest, high blood pressure second, tobacco smoking third, physical inactivity fourth and diabetes fifth. The cumulative risk-factor profile revealed that 35.6 and 21% of this study population had two and three risk factors, respectively.Conclusions: The study demonstrated a high prevalence of risk factors for noncommunicable diseases, e.g. large waist circumference, high BMI,raised blood pressure, tobacco smoking and raised blood glucose levels. Serious consideration should be given to this escalating burden of lifestylediseases in the study population. The development and implementation of relevant health promotion and intervention programmes that will improvethe general health and reduce the risk for noncommunicable diseases in this population are advised.Keywords: risk; lifestyle; chronic disease

Anti-Diarrheal Mechanism of the Traditional Remedy Uzara via Reduction of Active Chloride Secretion

BACKGROUND AND PURPOSE: The root extract of the African Uzara plant is used in traditional medicine as anti-diarrheal drug. It is known to act via inhibition of intestinal motility, but malabsorptive or antisecretory mechanisms are unknown yet. EXPERIMENTAL APPROACH: HT-29/B6 cells and human colonic biopsies were studied in Ussing experiments in vitro. Uzara was tested on basal as well as on forskolin- or cholera toxin-induced Cl(-) secretion by measuring short-circuit current (I(SC)) and tracer fluxes of (22)Na(+) and (36)Cl(-). Para- and transcellular resistances were determined by two-path impedance spectroscopy. Enzymatic activity of the Na(+)/K(+)-ATPase and intracellular cAMP levels (ELISA) were measured. KEY RESULTS: In HT-29/B6 cells, Uzara inhibited forskolin- as well as cholera toxin-induced I(SC) within 60 minutes indicating reduced active chloride secretion. Similar results were obtained in human colonic biopsies pre-stimulated with forskolin. In HT-29/B6, the effect of Uzara on the forskolin-induced I(SC) was time- and dose-dependent. Analyses of the cellular mechanisms of this Uzara effect revealed inhibition of the Na(+)/K(+)-ATPase, a decrease in forskolin-induced cAMP production and a decrease in paracellular resistance. Tracer flux experiments indicate that the dominant effect is the inhibition of the Na(+)/K(+)-ATPase. CONCLUSION AND IMPLICATIONS: Uzara exerts anti-diarrheal effects via inhibition of active chloride secretion. This inhibition is mainly due to an inhibition of the Na(+)/K(+)-ATPase and to a lesser extent to a decrease in intracellular cAMP responses and paracellular resistance. The results imply that Uzara is suitable for treating acute secretory diarrhea

Phytoplankton evolution during the creation of a biofloc system for shrimp culture

[EN] Microalgae play a key role in the dynamics of biofloc technology aquaculture systems. Some phytoplankton groups, such as diatoms, are desired for their high nutritional value and contribution to water quality. Other groups, such as cyanobacteria, are undesired because of their low nutritional value and capacity of producing toxins. So, monitoring the phytoplankton community structure and succession is key for managing biofloc systems. However, research on phytoplankton in these systems is scarce and mostly done by microscopy. The primary objective of this research was to estimate phytoplankton community structure in shrimp biofloc system water samples, using high-performance liquid chromatography methods and CHEMTAX software. The major groups present in our system were diatoms, euglenophytes, cyanobacteria and chlorophytes, while dinoflagellates were only remarkable at the initial period. We observed a clear dominance of diatoms all along the 5 months that comprised a complete biofloc system culture. The characteristic succession of autotrophic processes by heterotrophs of the biofloc systems, was observed by the reduction of net primary production. Light intensity played a key role in determining the phytoplankton composition and abundance. Algal pigment analyses using high-performance liquid chromatography and subsequent CHEMTAX analysis in water samples was useful for estimating the phytoplankton community structure in the biofloc systems. However, we found some limitations when the biofloc system was in heterotrophic mode. Under these conditions, some dinoflagellates and cyanobacteria behaved as heterotrophs and lost or decreased their biomarkers pigments. So, further research is needed to increase knowledge on the accuracy of high-performance liquid chromatography /CHEMTAX under these conditions.Financial support for this research was provided by Conselleria d’Educació, Investigació, Cultura i Esport of the Generalitat Valenciana, through the program VALi+D, fle number ACIF/2014/244. We would like to express our deepest thanks to Professor Luis Henrique da Silva Poersch of FURG (Universidade Federal do Rio Grande) and Ivan Vidal (Langostinos el Real) for his support. Finally, the authors wish to thank Le Gouessant and Michaël Metz for providing the commercial feed.Llario-Sempere, F.; Rodilla, M.; Escrivá-Perales, J.; Falco, S.; Sebastiá-Frasquet, M. (2018). Phytoplankton evolution during the creation of a biofloc system for shrimp culture. 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Levofloxacin versus placebo for the prevention of tuberculosis disease in child contacts of multidrug-resistant tuberculosis: study protocol for a phase III cluster randomised controlled trial (TB-CHAMP)

Background Multidrug-resistant (MDR) tuberculosis (TB) presents a challenge for global TB control. Treating individuals with MDR-TB infection to prevent progression to disease could be an effective public health strategy. Young children are at high risk of developing TB disease following infection and are commonly infected by an adult in their household. Identifying young children with household exposure to MDR-TB and providing them with MDR-TB preventive therapy could reduce the risk of disease progression. To date, no trials of MDR-TB preventive therapy have been completed and World Health Organization guidelines suggest close observation with no active treatment. Methods The tuberculosis child multidrug-resistant preventive therapy (TB-CHAMP) trial is a phase III cluster randomised placebo-controlled trial to assess the efficacy of levofloxacin in young child contacts of MDR-TB cases. The trial is taking place at three sites in South Africa where adults with MDR-TB are identified. If a child aged < 5 years lives in their household, we assess the adult index case, screen all household members for TB disease and evaluate any child aged < 5 years for trial eligibility. Eligible children are randomised by household to receive daily levofloxacin (15–20 mg/kg) or matching placebo for six months. Children are closely monitored for disease development, drug tolerability and adverse events. The primary endpoint is incident TB disease or TB death by one year after recruitment. We will enrol 1556 children from approximately 778 households with an average of two eligible children per household. Recruitment will run for 18–24 months with all children followed for 18 months after treatment. Qualitative and health economic evaluations are embedded in the trial. Discussion If the TB-CHAMP trial demonstrates that levofloxacin is effective in preventing TB disease in young children who have been exposed to MDR-TB and that it is safe, well tolerated, acceptable and cost-effective, we would expect that that this intervention would rapidly transfer into policy. Trial registration ISRCTN Registry, ISRCTN92634082. Registered on 31 March 2016