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Item Ad libitum water consumption prevents exercise-associated hyponatremia and protects against dehydration in soldiers performing a 40-km route-march(BioMed Central, 2019-01) Nolte, Heinrich W.; Nolte, Kim; Hew-Butler, TamaraBackground: It remains unclear if ad libitum water drinking, as a hydration strategy, prevents exercise-associated hyponatremia (EAH) during prolonged exercise. The aim of this study was to determine the incidence of EAH within the broader context of fluid regulation among soldiers performing a 40-km route-march ingesting water ad libitum. Methods: Twenty-eight healthy male soldiers participated in this observational trial. Pre- and post-exercise body mass, blood and urine samples were collected. Blood samples were assessed for serum sodium ([Na+]), glucose, creatinine, urea nitrogen (BUN), plasma osmolality, creatine kinase (CK), and plasma arginine vasopressin (AVP) concentrations. Plasma volume (PV) was calculated using hematocrit and hemoglobin. Urine samples were analyzed for osmolality and [Na+]. Water intake was assessed by weighing bottles before, during and after the march. The mean relative humidity was 55.7% (21.9–94.3%) and the mean dry bulb temperature was 27.1 °C (19.5 °C - 37.0 °C) during the exercise. Results: Twenty-five soldiers (72 ± 10 kg) (Mean ± SD) completed the march in 09:11 ± 00:43 (hr:min). Participants consumed 736 ± 259 ml/h of water and lost 2.8 ± 0.9 kg (4.0% ± 1.4%, P < 0.05) of body mass. Significant (pre-march vs. post-march; P < 0.05) decreases in serum [Na+] (141 mmol/L vs. 136 mmol/L), plasma osmolality (303 mOsmol/kg H2O vs. 298 mOsmol/kg H2O), and serum creatinine (111 μmol/L vs. 101 μmol/L) and urine [Na+] (168 mmol/L vs. 142 mmol/L), as well as significant increases in plasma AVP (2 pg/ml vs. 11 pg/ml), plasma CK (1423 U/L vs. 3894 U/L) and urine osmolality (1035 mOsmol/kg H2O vs. 1097 mOsmol/kg H2O) were found. The soldier (72 kg) with the lowest postexercise sodium level completed the march in 08:38. He drank 800 ml/h, lost 2% body mass, and demonstrated (prepost) increases in plasma osmolality (294–314 mOsmol/kg H2O), BUN (20–30 mg/dl), AVP (2–16 pg/ml) and PV (41%). His urine osmolality decreased from 1114 mOsmol/kg H2O to 1110 mOsmol/kg H2O. No participants finished the route-march with a serum [Na+] indicating hypernatremia (range, 134–143 mmol/L). Conclusions: Ad libitum drinking resulted in 4% body mass loss with a 2 mmol/L serum [Na+] reduction in conjunction with high urine osmolality (> 1000 mOsmol/kg H2O) and plasma AVP. No single hydration strategy likely prevents EAH, but hypernatremia (cellular dehydration) was not seen despite > 2% body mass losses and high urine osmolality.Item Evaluation of automated malaria diagnosis using the Sysmex XN-30 analyser in a clinical setting(BioMed Central, 2019-01) Pillay, Evashin; Bezuidenhout, Belinda C.; Coetzer, Thérèsa L.; Khodaiji, Shanaz; Litshie, MonwabisiBackground: Early and accurate diagnosis of malaria is a critical aspect of eforts to control the disease, and several diagnostic tools are available. Microscopic assessment of a peripheral blood smear enables direct visualization of parasites in infected red blood cells and is the clinical diagnostic gold standard. However, it is subjective and requires a high level of skill. Numerous indirect detection methods are in use, but are not ideal since surrogate markers of infection are measured. This study describes the frst clinical performance evaluation of the automated Sysmex XN-30 analyser, which utilizes fuorescence fow cytometry to directly detect and quantitate parasite-infected red blood cells. Results: Residual EDTA blood samples from suspected malaria cases referred for routine diagnosis were analysed on the XN-30. Parasitaemia was reported as a percentage, as well as absolute numbers of infected red blood cells, and scattergrams provided a visual image of the parasitized red blood cell clusters. The results reported by the XN-30 correlated with microscopy and the analyser demonstrated 100% sensitivity and specifcity. Measurements were reproducible and storage of samples at room temperature did not afect the parameters. Several Plasmodium species were detected, including Plasmodium falciparum, Plasmodium vivax and Plasmodium ovale. The XN-30 also identifed the transmissible gametocytes as a separate cluster on the scattergrams. Abnormal red blood cell indices (low haemoglobin and raised reticulocyte counts), haemoglobinopathies and thrombocytopenia did not interfere with the detection of parasites. The XN-30 also generated a concurrent full blood count for each sample. Conclusions: The novel technology of the Sysmex XN-30 provides a robust, rapid, automated and accurate platform for diagnosing malaria in a clinical setting. The objective enumeration of red blood cells infected with Plasmodium species makes it suitable for global use and allows monitoring of the parasite load once therapy has been initiated, thereby providing an early marker of drug resistance. The automated generation of a full blood count for each sample provides an opportunity for detecting unsuspected cases. Asymptomatic carriers can also be identifed, which will be useful in blood transfusion centres, and will enable treatment of these individuals to prevent the spread of the disease.Item Exploring the sorting of patients in community health centres across Gauteng Province, South Africa(BioMed Central, 2019-01) Stott, B. A.; Moosa, S.Background: Primary health care worldwide faces large numbers of patients daily. Poor waiting times, low patient satisfaction and staff burnout are some problems facing such facilities. Limited research has been done on sorting patients in non-emergency settings in Africa. This research looked at community health centres (CHCs) in Gauteng Province, South Africa where queues appear to be poorly managed and patients waiting for hours. This study explores the views of clinicians in CHCs across Gauteng on sorting systems in the non-emergency ambulatory setting. Methods: The qualitative study design used one-to-one, in-depth interviews of purposively selected doctors. Interviews were conducted in English, with open-ended exploratory questions. Interviews were recorded, transcribed, anonymised and checked by interviewees later. Data collection and analysis stopped with information saturation. The co-author supervised and cross-checked the process. A thematic framework was developed by both authors, before final thematic coding of all transcripts was undertaken by the principal author. This analysis was based on the thematic framework approach. Results: Twelve primary health care (PHC) doctors with experience in patient sorting, from health districts across Gauteng, were interviewed. Two themes were identified, two major themes, namely Systems Implemented and Innovative Suggestions, and Factors Affecting Triage. Systems Implemented included those using vital signs, sorting by specialties, and using the Integrated Management of Childhood Illnesses approach. Systems Implemented also included doctor - nurse triage, first come first serve, eyeball triage and sorting based on main complaint. Innovative Suggestions, such as triage room treatment and investigations, telephone triage, longer clinic hours and a booking system emerged. There were three Factors Affecting Triage: Management Factor, including general management issues, equipment, documentation, infrastructure, protocol, and uniformity; and Staff Factor, including general staffing issues education and teamwork; and Patient Factor. Conclusion: Developing a functional triage protocol with innovative systems for Gauteng is important. Findings from this study can guide the development of a functional triage system in the primary health care non-emergency outpatient setting of Gauteng’s CHCs. The Emergency Triage, Assessment and Treatment (ETAT) tool, modified for adult and non-clinician use, could help this. However, addressing management, staff and patient factors must be integral.Item Lipid levels, insulin resistance and cardiovascular risk over 96 weeks of antiretroviral therapy: a randomised controlled trial comparing low-dose stavudine and tenofovir(BioMed Central, 2018-12) Vos, Alinda G.; Chersich, Matthew F.; Klipstein‑Grobusch, Kerstin; Zuithof, Peter; Moorhouse, Michelle A.; Lalla‑Edward, Samanta T.; Kambugu, Andrew; Kumarasamy, N.; Grobbee, Diederick E.; Barth, Roos E.; Venter, Willem D.Background: HIV infection and antiretroviral treatment are associated with changes in lipid levels, insulin resistance and risk of cardiovascular disease (CVD). We investigated these changes in the first 96 weeks of treatment with lowdose stavudine or tenofovir regimens. Methods: This is a secondary analysis of a double blind, randomised controlled trial performed in South-Africa, Uganda and India comparing low-dose stavudine (20 mg twice daily) with tenofovir in combination with efavirenz and lamivudine in antiretroviral-naïve adults (n = 1067) (Clinicaltrials.gov, NCT02670772). Over 96 weeks, data were collected on fasting lipids, glucose and insulin. Insulin resistance was assessed with the HOMA-IR index and 10-year CVD risk with the Framingham risk score (FRS). A generalized linear mixed model was used to estimate trends over time. Results: Participants were on average 35.3 years old, 57.6% female and 91.8% Black African. All lipid levels increased following treatment initiation, with the sharpest increase in the first 24 weeks of treatment. The increase in all lipid subcomponents over 96 weeks was higher among those in the stavudine than the tenofovir group. Insulin resistance increased steadily with no difference detected between study groups. FRS rose from 1.90% (1.84–1.98%) at baseline to 2.06 (1.98–2.15%) at week 96 for the total group, with no difference between treatment arms (p = 0.144). Lipid changes were more marked in Indian than African participants. Conclusion: Lipid levels increased in both groups, with low-dose stavudine resulting in a worse lipid profile compared to tenofovir. Insulin resistance increased, with no difference between regimens. CVD risk increased over time and tended to increase more in the group on stavudine. The low CVD risk across both arms argues against routine lipid and glucose monitoring in the absence of other CVD risk factors. In high risk patients, monitoring may only be appropriate at least a year after treatment initiation.Item A comparison between raw and predicted mortality in a paediatric intensive care unit in South Africa(BioMed Central, 2018-11) Ballot, Daynia Elizabeth; Ramdin, TanushaObjective: Paediatric intensive care resources are limited in sub-Saharan Africa. The mortality rate in a combined Paediatric/Neonatal Intensive Care Unit in Johannesburg, South Africa was almost double that in a dedicated paediatric intensive care unit in the same country. This study aimed to compare the raw mortality rate with that predicted with the Paediatric Index of Mortality (version 3), by doing a retrospective analysis of an existing database. Results: A total of 530 patients admitted to the intensive care unit between 1 January 2015 and 31 December 2017 were included. The raw mortality rate was 27.1% and the predicted mortality rate was 27.0% (p = 0.971). Cardiac arrest during ICU admission (p < 0.001), non-reactive pupils (0.035), inotropic support (p < 0.001) and renal disease (p = 0.002) were all associated with an increased risk of mortality. These findings indicate that the high mortality rate is due to the severity of illness in the patients that are admitted. It also indicates that the quality of care delivered is acceptable.Item Associations between sleep parameters, non-communicable diseases, HIV status and medications in older, rural South Africans(Nature Research, 2018-11) Gómez-Olivé, F. Xavier; Rohr, Julia K.; Roden, Laura C.; Rae, Dale E.; von Schantz, MalcolmAs part of the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI), we investigated sleep habits and their interactions with HIV or non-communicable diseases (NCDs) in 5059 participants (median age: 61, interquartile range: 52—71, 54% females). Selfreported sleep duration was 8.2±1.6h, and bed and rise times were 20:48±1:15 and 05:31±1:05 respectively. Ratings of insufcient sleep were associated with older age, lack of formal education, unemployment, and obesity (p<0.05). Ratings of restless sleep were associated with being older, female, having more education, being unemployed, and single. Hypertension was associated with shorter self-reported sleep duration, poor sleep quality, restless sleep, and periods of stopping breathing during the night (p<0.05). HIV positive individuals not on antiretroviral treatment (ART) reported more nocturnal awakenings than those on ART (p=0.029) and HIV negative individuals (p=0.024), suggesting a negative net efect of untreated infection, but not of ART, on sleep quality. In this cohort, shorter, poor-quality sleep was associated with hypertension, but average self-reported sleep duration was longer than reported in other regions globally. It remains to be determined whether this is particular to this cohort, South Africa in general, or low- to middle-income countries undergoing transition.Item Developing a model for integrating sexual and reproductive health services with HIV prevention and care in KwaZulu-Natal, South Africa(BioMed Central, 2018-11) Milford, Cecilia; Scorgie, Fiona; Greener, Letitia Rambally; Mabude, Zonke; Beksinska, Mags; Harrison, Abigail; Smit, JenniferBackground: There are few rigorous studies evaluating the benefits of vertical versus integrated delivery of healthcare services, and limited published studies describing conceptual models of integration at service-delivery level in public healthcare facilities. This article seeks to fill this gap, by describing the development of a district-based model for integrating sexual and reproductive health (SRH) and HIV services in KwaZulu-Natal, South Africa. Methods: Baseline data were collected from seven urban public healthcare facilities through client and provider interviews, and a facility inventory was completed to assess current service integration practices. Feedback sessions were held with health providers from participating facilities to share data collected and explore appropriate integration scenarios. A conceptual model of potential service integration was then designed, and subsequently implemented and evaluated in the research sites. Results: Key principles of the model included a focus on health system strengthening and strong community input and involvement. The model was designed primarily to support the integration of family planning into HIV services, and included measures to improve client and commodity monitoring; capacity building through training and mentorship; and a ‘health navigation’ strategy to strengthen referrals within and between public healthcare facilities. Endline evaluation data were collected in the same facilities following implementation of the model. Conclusions: This manuscript demonstrates the utility of the conceptual model. It shows that service integration can be accomplished in a phased manner with support of community and healthcare providers. In addition, local context must be taken into account and the components of the model should be flexible to suit the needs of the health system.Item Spin-3/2 dark matter in a simple t-channel model(Springer Open, 2018-11) Khojali, Mohammed Omer; Kumar, Mukesh; Cornell, Alan S.; Goyal, AshokWe consider a spin-3/2 fermionic dark matter (DM) particle interacting with the Standard Model quarks through the exchange of a charged and coloured scalar or vector mediator in a simple t-channel model. It is found that for the vector mediator case, almost the entire parameter space allowed by the observed relic density is already ruled out by the direct detection LUX data. No such bounds exist on the interaction mediated by scalar particles. Monojet + missing energy searches at the Large Hadron Collider provide the most stringent bounds on the parameters of the model for this case. The collider bounds put a lower limit on the allowed DM masses.Item Large N bilocals at the infrared fixed point of the three dimensional O(N) invariant vector theory with a quartic interaction(Springer, 2018-11) Mulokwe, Mbavhalelo; Rodrigues, Jo˜ao P.We study the three dimensional O(N) invariant bosonic vector model with a λN(φaφa)2 interaction at its infrared fixed point, using a bilocal field approach and in an 1/N expansion. We identify a (negative energy squared) bound state in its spectrum about the large N conformal background. At the critical point this is identified with the ∆ = 2 state. We further demonstrate that at the critical point the ∆ = 1 state disappears from the spectrum.Item Death of preceding child and maternal healthcare services utilisation in Nigeria: investigation using lagged logit models(BioMed Central, 2018-11) Akinyemi, Joshua O.; Bolajoko, Izzatullah; Gbadebo, Babatunde M.Background: One of the factors responsible for high level of childhood mortality in Nigeria is poor utilization of maternal healthcare (MHC) services. Another important perspective which has been rarely explored is the influence of childhood death on MHC service utilization. In this study, we examined the relationship between death of preceding child and MHC services utilization [antenatal care (ANC), skilled attendant at birth (SAB), and postnatal care (PNC)] among Nigerian women and across the six geo-political zones of the country. Methodology: We analyzed reproductive history dataset for 16,747 index births extracted from the 2013 Nigeria Demographic and Health Survey. The main explanatory variable was survival status of preceding child; therefore, only second or higher order births were considered. Analysis involved the use of descriptive statistics and lagged logit models fitted for each measure of MHC utilization. Association and statistical significance were expressed as adjusted odds ratio (AOR) with 95% confidence interval. Results: The use of MCH services for most recent births in the 2013 Nigeria DHS were ANC (56.0%), SAB (34.7%), and PNC (27.3%). Univariate models revealed that the death of preceding child was associated with lesser likelihood of ANC (OR = 0.64, CI 0.57–0.71), SAB (OR = 0.56, CI 0.50–0.63), and PNC (OR = 0.65, CI 0.55–0.69). Following adjustment for maternal socio-economic and bio-demographic variables, statistical significance in the relationship disappeared for the three MHC indicators: ANC (AOR = 1.00, CI 0.88–1.14), SAB (AOR = 0.97, CI 0.81–1.15), and PNC (AOR = 0.95, CI 0.83–1.11). There were no significant variations across the six geo-political regions in Nigeria. The likelihood of ANC utilization was higher when the preceding child died in Northcentral (AOR = 1.19, CI 0.84–1.70), Northeast (AOR = 1.26, CI 0.99–1.59), and South-south (AOR = 1.19, CI 0.72–1.99) regions while the reverse is the case in Southeast (AOR = 0.39, CI 0.23–0.60). For the Southeast, similar result was obtained for ANC, SAB, and PNC. Conclusion: Death of a preceding child does not predict MHC services use in Nigeria especially when maternal socio-economic characteristics are controlled. Variations across the Northern and Southern regions did not attain statistical significance. Interventions are needed to reverse the pattern such that greater MHC utilization is recorded among women who have experienced child death.