The challenge of Lake Chilwa

Lake Chilwa and its environs present a unique challenge to science for two reasons: 1. The welfare of its people and the fish and crops on which they depend on incomes as well as subsistence are dominated by the vagaries of the periodic rise and fall of the lake. Inyears of high level the lake provides a relatively good living for the people of the plain and the fish is a major source of dietary protein for the densely populated Shire Highlands. Fish catches and fish consumption decline in years of low lake level. Could knowledge of the biology of the lake and the hydrology of the lake basin assist in stabilizing the fishing industry? 2. The area is underdeveloped, with the traditional matrilineal way of life, but it has considerable potential for a fishing industry, for agriculture, for livestock, for bird preservation and tourism and possibly, at some future date, for minerals. How can these interests be reconciled and in what order should developments take place

Breast feeding practices and views among diabetic women: a retrospective cohort study

Objective: to explore the pattern and experiences of breast-feeding practices among diabetic women. Design: retrospective cohort study using maternal records and postal questionnaires in a Baby-Friendly hospital. Participants: diabetic mothers including women with gestational diabetes, and type 1 and 2 diabetes mellitus. Findings: from the total group of respondents, 81.9% intended to breast feed. The actual breast feeding rates were 81.9% at birth, 68.1% at 2 weeks and 28.7% at 6 months postpartum. Major themes that were identified from women's experiences included information and advice, support vs. pressure, classification and labelling, and expectations. Conclusions: more than two-thirds of the diabetic women intended to breast feed and actually did breast feed in this study. For both the total study population and the type 1 and 2 diabetics alone, more than half were still breast feeding at 2 weeks postpartum, and approximately one-third were still breast feeding at 6 months postpartum. Implications for practice: structured support, provided for women through Baby-Friendly initiatives, was appreciated by the diabetic women in this study. The extent to which this support influenced the highly successful breast feeding practices in this group of women needs focused investigation. The need for a delicate balancing act between pressure and advice in order to prevent coercion was noted.</p

A methodology for comparing news coverage of elite cues during presidential elections

Throughout the last two presidential elections, Donald Trump weaponized the news media in various ways; either by appearing on conservative programming to gain more popularity with a right-wing base or by attacking journalists or news outlets with claims of liberal bias in an attempt to discredit the industry. Trump is not the first politician to utilize such a strategy, earlier research revealed evidence that public perception of a biased news media increased from 1988 to 1996. This study aimed to update that initial research by providing a content analysis of political news coverage leading up to the 2016 and 2020 elections while also analyzing public opinion regarding news biases during this time period. Results from this study showed evidence for all hypotheses; a rise in news coverage of elite cues also led to a rise in public perception that political news media coverage has a liberal bias, presidential candidates and party officials were more likely to claim a liberal than conservative news media bias, and finally, claims of liberal bias in news coverage were more likely to suggest that media bias exists across the entire media industry than claims of conservative bias. While conservative politicians and party officials are quick to charge a liberal media bias, the opposite scenario seems to be happening in U.S. media; news outlets are reporting Republican candidates and messaging with more favorable coverage compared to Democrats on the other side of the political aisle.Thesis (M.A.

A longitudinal analysis of neonatal and infant diagnostic HIV-PCR uptake and associations during three sequential policy periods in Mitchell’s Plain, Cape Town

Background: Despite technological and programmatic advances in the prevention of vertical transmission of HIV and early infant diagnosis (EID), paediatric HIV continues to have a significant impact on infant and child survival in low- and middle-income countries. Many EID programmes follow the WHO recommendation of initial infant HIV testing with a nucleic acid assay at 4-6 weeks old. In general this strategy has been poorly implemented with substantial attrition after birth such that, according to UNAIDS, only 51% of HIV-exposed infants received a virological test in the first two months of life in 2015. In addition, there is concern about the sensitivity of the nucleic acid assays at six weeks in the context of exposure to prolonged multidrug antiretroviral therapy as infant post-exposure prophylaxis, and in breast milk. HIV-PCR testing at birth has been promoted as a means of maximizing the number of infants who receive an HIV test as well as identifying in utero-infected infants in whom HIV infection may follow an aggressive course. Evidence from pilot studies and modelling data was sufficiently compelling for the WHO to include a conditional recommendation for the addition of a birth HIV-PCR (either routine or targeted at high risk groups) to its EID algorithms in 2015. The Western Cape introduced targeted birth HIV testing for high risk infants in August 2014 and expanded this in line with the South African National Prevention of Mother-to-Child Transmission Guidelines, to include all HIV-exposed infants in December 2015. Methods: Between 2013 and 2016 we conducted an implementation science project to iteratively assess the implementation and effectiveness of the vertical transmission prevention of HIV in a chain of referral facilities in Cape Town (i.e. from primary to tertiary care). The e-register provided a single longitudinal record for each woman (linked to her infant after birth) and enabled assessment of HIV testing and treatment from first antenatal visit through delivery to infant HIV testing. Using a cohort of HIV-exposed live infants from this database, a protocol was designed (Section A: Protocol) to assess the implementation and outcome of effectively three different EID policy periods in the facility chain. i.e. an initial period of birth HIV-PCR at the clinician’s discretion if evidence of HIV infection; a period of targeted birth testing of high risk infants and lastly, of routine birth HIV-PCR for all HIV-exposed infants. A critical review of the literature appraised published assessments of birth HIV testing programmes in low- and middle-income countries (Section B: Literature Review) with the aim of assessing in utero transmission rates, follow-up testing and transmission rates and the resources required for implementation. Studies that modelled the impact of birth HIV testing were specifically reviewed. The manuscript (Section C: Manuscript) presented an analysis of the HIV-infected/exposed mother/infant dyads from the e-register of the Closing the Gaps study. Using this database adherence to guidelines in each period was assessed as well as the outcome of HIV-PCR at four delivery sites and the impact of the policies on return for follow-up EID. Results: South Africa is the first country in sub-Saharan Africa to implement birth HIV testing and most of the studies in support of this strategy were generated here. There was limited literature which highlighted the need for further investigation into the implementation and effectiveness of such programmes. No prospective data addressed targeted birth testing and those reporting on more routine birth HIV-PCR demonstrated success in timeous diagnosis and treatment although significant additional project resources were required. The retrospective laboratory data indicated that receipt of a birth HIV-PCR reduced the likelihood for follow-up at later testing time-points. This is important as the modelling studies suggested that the clinical and financial benefits of adding birth testing to existing algorithms would be lost if follow-up was poor. In the cohort of 2012 HIV-exposed infants in the study presented in the manuscript, the proportion who received birth testing increased with the progression of the EID policies but guideline implementation was poor, especially in primary care, with only 60% of infants being tested as recommended. The proportion of infants with positive HIV-PCR decreased as the pool of HIV-exposed infants undergoing testing expanded, being highest during the periods of targeted birth testing. In concurrence with the South African literature, receipt of a birth HIV-PCR decreased the likelihood of follow-up testing at 6-10 weeks. Among infants tested at 6-10 weeks old, the proportion who were positive for the first time at this time- point increased with the introduction of routine birth testing for all HIV-exposed infants, emphasizing the importance of the follow-up EID time-points. Conclusion: Virological testing at birth effectively increased the number of HIV-exposed infants who received an HIV test and was effective in identifying in utero infection in high risk infants (who could start treatment early with the attendant benefits.) The Western Cape EID policies were incompletely implemented in the study facilities over this time with many infants not being tested as indicated. Birth HIV-PCR decreased follow-up testing, an unintended consequence of serious concern. Adherence to the provincial and national guidelines needs to be re-enforced at delivery sites and at the primary care facilities where follow-up EID occurs

Neuroinflammmation in alcohol dependence

Alcohol dependence damages the brain through a multiplicity of factors including thiamine deficiency, liver disease, head injuries, and repeated episodes of alcohol withdrawal. Alcohol withdrawal is a potential opportunity for reducing damage as it is an intensive time of contact between doctors and patients. Pre-clinical models of alcohol dependence have demonstrated activation of microglia, resident tissue macrophages, and expression of cytokines and other inflammatory mediators both in the brain and peripheral blood during alcohol withdrawal. These changes were associated with neuronal death, and learning deficits. Similar processes may occur in man as increased microglial numbers, increased chemokine expression and raised circulating pro-inflammatory cytokines have been reported in alcohol dependence. The aim of the thesis was to characterise the peripheral cytokine profile during alcohol detoxification, to investigate whether there are relationships between peripheral cytokines and clinical features of alcohol withdrawal, to investigate neuroinflammation in alcohol dependence by using [11C]PBR28 Positron Emission Tomography to assess microglial activation in recently abstinent alcohol dependent patients in vivo and to investigate how these processes relate to elevated cortisol and elevated cerebral glutamate reported in alcohol withdrawal respectively. The longitudinal study undertaken in 51 alcohol dependent patients during detoxification demonstrated that both pro- and anti-inflammatory cytokines, and chemokines, decreased significantly during detoxification while T cell cytokines increase. IL-6 was positively associated with withdrawal severity and depressive symptoms during withdrawal. The chemokine CCL-2 was positively associated with performance on cognitive tasks. Serum cortisol was in the high normal range and decreased during detoxification. The salivary Cortisol Awakening Response (CAR) was also in the normal range at all time points. Both serum cortisol and the CAR were positively correlated with IL-6 concentrations suggesting hyperfunction of the HPA axis during alcohol detoxification may relate in part to inflammatory stimulation. The PET study comparing alcohol dependent men in early abstinence and healthy controls was undertaken using the ligand, [11C]PBR28 that binds to the Translocator Protein 18 kDa (TSPO) richly expressed in microglia. Alcohol dependent patients had lower TSPO binding in the hippocampi than healthy controls. TSPO binding in the hippocampus was also positively correlated with performance on tests of verbal memory. This suggests that hippocampal microglial loss or dysfunction may be related to memory problems in alcohol dependence. Given that benzodiazepines are used to treat alcohol withdrawal, an in vitro binding study was conducted to investigate whether benzodiazepines would significantly block [11C]PBR28 binding and found that benzodiazepines do not block a significant proportion of TSPO at all but the highest clinical doses. The relationship between brain glutamate, as measured with Magnetic Resonance Spectroscopy, and microglial activation was investigated. Alcohol dependent patients had significantly lower glutamate + glutamine (Glx) concentrations in the occipital cortex with no difference in glutamate concentrations in the anterior cingulate cortex (ACC). In summary, there are changes in both peripheral and brain inflammatory processes in early abstinence from alcohol dependence that are related to clinical symptoms. Peripheral pro-inflammatory cytokines are raised early in detoxification relative to late detoxification and are related to withdrawal and affective symptoms. Surprisingly, evidence of decreased microglial function in the hippocampus was found and this related to poorer cognitive function, suggesting a positive role for immune cells in the brain in alcohol dependence. Inflammatory processes were related to HPA axis function during detoxification but not to changes in brain glutamate concentrations. In conclusion, characterisation of inflammation through multiple approaches in this series of studies demonstrates the likely importance of such processes and provides novel approaches for treatment to reduce brain damage due to alcoholism.Open Acces