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Publication Menopausal symptoms, menopausal stage and cognitive functioning in black urban African women(Taylor & Francis Online, 2019-08-28)Objective: Studies, conducted largely in North America and Europe, demonstrate that menopausal symptoms and menopausal stage influence cognitive function. Here, we evaluate these associations in a large cohort of sub-Saharan African women, a population where these associations are understudied. We hypothesized that premenopausal women would show better cognitive performance than women later in the transition, and that menopausal symptoms would be inversely related to cognition. Methods: This cross-sectional study included 702 black urban South African women between the ages of 40 and 60 years from the Study of Women Entering and in Endocrine Transition. Participants completed the Symbol Digit Modalities Test, a measure of processing speed and incidental recall. Menopausal stage was ascertained using the Stages of Reproductive Aging Workshop+ 10 criteria and symptoms using the Menopause Rating Scale. Multivariable linear regression analyses were used to examine adjusted associations between menopausal stage and menopausal symptoms on cognitive performance. Results: In adjusted analyses, menopausal stage was not associated with processing speed (p = 0.35) or incidental recall (p = 0.64). However, more severe symptoms of hot flushes and anxiety were associated with slower processing speed (all p < 0.05), and more severe mood symptoms were associated with worse incidental recall (p = 0.008).Conclusion: Menopausal symptoms, but not menopausal stage, were associated with cognitive function in this cross-sectional study of sub-Saharan African women.Publication Neural correlates of maintenance working memory, as well as relevant structural qualities, are associated with earlier antiretroviral treatment initiation in vertically transmitted HIV(Springer Nature, 2019-09-03)There is evidence of HIV affecting cognitive functioning across age groups, with adult studies showing related deficits in frontostriatal and hippocampal regional activity. Additionally, delayed initiation of antiretroviral treatment (ART) has been associated with poorer cognitive outcomes in HIV-infected youth. Little is known, however, of the neural correlates underlying such cognitive deficits in youth populations. We investigated maintenance working memory–related brain activity in South African HIV-infected youth and controls, and the effect of ART initiation age on underlying structures. Sixty-four perinatally infected youth (ages 9–12) and 20 controls (ages 9–13) underwent functional magnetic resonance imaging (fMRI) while completing 1-back and 0-back blocks of the N-back task. At an uncorrected p value threshold of 0.001, the HIV-infected group showed decreased activation in the left superior temporal gyrus, pre- and postcentral gyri, insula, and putamen as well as bilateral hippocampus, and mid cingulum. The HIV patients with delayed ART initiation showed less activation during processing conditions in the mid cingulum; left inferior parietal gyrus; and right inferior frontal, bilateral thalamic, and superior temporal regions. When these regions were tested for structural differences, the mid cingulum and right inferior frontal gyrus, insula, and thalamus were found to have less cortical thickness, surface area, or volume in the group with delayed ART initiation. Regional differences between HIV-infected youth and controls noted in the N-back task are consistent with impairments in structures involved in maintenance working memory. These data support earlier ART initiation in perinatally infected individuals.Item Muscle mass measures and incident osteoporosis in a large cohort of postmenopausal women(Wiley, 2018-11-05)Background: Despite several muscle mass measures being used in the current definitions of sarcopenia, their usefulness is uncertain because of limited data on their association with health outcomes. The aim of the study was to compare the performance of different muscle mass measures for predicting incident osteoporosis in postmenopausal women. Methods: This study included data from 149 166 participants (aged 60.3 ± 5.5 years) as part of the UK Biobank cohort. Body composition was assessed using bioelectrical impedance. The muscle mass measures included were total body skeletal muscle mass (SMM) and appendicular SMM (aSMM) divided by height squared (ht2 ), derived residuals, SMM, SMM adjusted for body mass (SMM/bm × 100), and aSMM normalized for body mass index (aSMM/BMI). Diagnoses of the events were confirmed by primary care physicians and coded according to the World Health Organization's International Classification of Diseases 10th Revision (ICD-10: M80-M82). Results: Over a median follow-up of 6.75 (5th to 95th percentile interval, 1.53 to 8.37) years, 394 newly diagnosed cases of osteoporosis occurred, with 40 (10.2%) cases being associated with a pathological fracture. SMM/ht2 , aSMM/ht2 residual, and SMM were lower in postmenopausal women with osteoporosis compared with women without (all P < 0.0001), while SMM/bm × 100 (P = 0.003), but not aSMM/BMI (P = 0.59), was higher in the osteoporosis group. The unadjusted rates of osteoporosis increased with decreasing quintiles for SMM/ht2 , aSMM/ht2 , residuals, and SMM (all P trend <0.0001), while the incidence of osteoporosis increased with increasing SMM/bm × 100 (P trend =0.001), but not for aSMM/BMI (P = 0.45). After minimally adjusting for age and after full adjustment, SMM/ht2 , aSMM/ht2 , and SMM were the only measure that consistently predicted osteoporosis in the total group of postmenopausal women [hazard ratio (HR) 0.65-0.67, all P ≤ 0.0001], in lean women (HR 0.62-0.68; all P ≤ 0.001), and women with increased adiposity (HR 0.64-0.68; all P ≤ 0.01). In fully adjusted models, the changes in the R2 statistic were 13.4%, 11.6%, and 15.3% for the SMM/ht2 (aSMM/ht2 ), residual, and SMM, but only 4.9% and 1.3% for SMM/bm × 100 and aSMM/BMI. Conclusions: Muscle mass measures adjusted for height only (SMM/ht2 , aSMM/ht2 ) appear to be better muscle-relevant risk factors for incident osteoporosis in postmenopausal women, including when stratified into lean participants and participants with increased adiposity.Item Urgency for South Africa to prioritise cardiovascular disease management(Elsevier, 2019-02)No abstract available.Item Helminth-induced IL-4 expands bystander memory CD8 T cells for early control of viral infection(Nature Communications, 2018-10-30)Infection with parasitic helminths can imprint the immune system to modulate bystander inflammatory processes. Bystander or virtual memory CD8 T cells (T) are non-conventional T cells displaying memory properties that can be generated through responsiveness to interleukin (IL)-4. However, it is not clear if helminth-induced type 2 immunity functionally affects the T compartment. Here, we show that helminths expand CD44CD62LCXCR3CD49d T cells through direct IL-4 signaling in CD8 T cells. Importantly, helminth-mediated conditioning of T cells provided enhanced control of acute respiratory infection with the murid gammaherpesvirus 4 (MuHV-4). This enhanced control of MuHV-4 infection could further be explained by an increase in antigen-specific CD8 T cell effector responses in the lung and was directly dependent on IL-4 signaling. These results demonstrate that IL-4 during helminth infection can non-specifically condition CD8 T cells, leading to a subsequently raised antigen-specific CD8 T cell activation that enhances control of viral infection.
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