Survival of patients with Kaposi’s sarcoma in the South African antiretroviral treatment era: A retrospective cohort study

Background. When South Africa (SA) implemented its antiretroviral therapy (ART) programme in 2004, the model for treating HIV-positive Kaposi’s sarcoma (KS) patients shifted from symptomatic palliation to potential cure. Objective. To evaluate survival and changes over time in AIDS-KS patients treated at a tertiary academic hospital oncology unit (the Steve Biko Academic Hospital medical oncology unit) in Pretoria, SA, in the context of ART availability in SA. Methods. We conducted a retrospective review of electronic and paper records of KS patients who accessed cancer care between May 2004 and September 2012. We used Kaplan-Meier survival functions to estimate 1- and 2-year survival, and Cox regression models to identify changes over time and prognostic factors. Results. Our study included 357 AIDS-KS patients, almost all of whom were black Africans (n=353, 98.9%); 224 (62.7%) were men. The median age at cancer diagnosis was 37 (interquartile range (IQR) 30 - 43) years, and the median baseline CD4+ count was 242 (IQR 130 - 403) cells/µL. Most patients received ART (n=332, 93.0%) before or after KS diagnosis; 169 (47.3%) were treated with chemotherapy and 209 (58.6%) with radiation therapy. Mortality was 62.7% lower (adjusted hazard ratio (HR) 0.37, 95% confidence interval (CI) 0.19 - 0.73) in the late (2009 - 2012) than in the early (2004 - 2008) ART period. Receiving chemotherapy (adjusted HR 0.3, 95% CI 0.15 - 0.61) and poor-risk AIDS Clinical Trials Group KS stage (adjusted HR 2.88, 95% CI 1.36 - 6.09) predicted mortality. Conclusions. Our results show that large national ART roll-out programmes can successfully reduce KS-related mortality at the individual patient level. If ART coverage is extended, KS-associated morbidity and mortality are likely to drop

Survival of patients with Kaposi’s sarcoma in the South African antiretroviral treatment era: A retrospective cohort study

Background. When South Africa (SA) implemented its antiretroviral therapy (ART) programme in 2004, the model for treating HIV-positive Kaposi’s sarcoma (KS) patients shifted from symptomatic palliation to potential cure.Objective. To evaluate survival and changes over time in AIDS-KS patients treated at a tertiary academic hospital oncology unit (the Steve Biko Academic Hospital medical oncology unit) in Pretoria, SA, in the context of ART availability in SA.Methods. We conducted a retrospective review of electronic and paper records of KS patients who accessed cancer care between May 2004 and September 2012. We used Kaplan-Meier survival functions to estimate 1- and 2-year survival, and Cox regression models to identify changes over time and prognostic factors.Results. Our study included 357 AIDS-KS patients, almost all of whom were black Africans (n=353, 98.9%); 224 (62.7%) were men. The median age at cancer diagnosis was 37 (interquartile range (IQR) 30 - 43) years, and the median baseline CD4+ count was 242 (IQR 130 - 403) cells/µL. Most patients received ART (n=332, 93.0%) before or after KS diagnosis; 169 (47.3%) were treated with chemotherapy and 209 (58.6%) with radiation therapy. Mortality was 62.7% lower (adjusted hazard ratio (HR) 0.37, 95% confidence interval (CI) 0.19 - 0.73) in the late (2009 - 2012) than in the early (2004 - 2008) ART period. Receiving chemotherapy (adjusted HR 0.3, 95% CI 0.15 - 0.61) and poor-risk AIDS Clinical Trials Group KS stage (adjusted HR 2.88, 95% CI 1.36 - 6.09) predicted mortality.Conclusions. Our results show that large national ART roll-out programmes can successfully reduce KS-related mortality at the individual patient level. If ART coverage is extended, KS-associated morbidity and mortality are likely to drop.

Zinc intake, status and indices of cognitive function in adults and children: a systematic review and meta-analysis

In developing countries, deficiencies of micronutrients are thought to have a major impact on child development; however, a consensus on the specific relationship between dietary zinc intake and cognitive function remains elusive. The aim of this systematic review was to examine the relationship between zinc intake, status and indices of cognitive function in children and adults. A systematic literature search was conducted using EMBASE, MEDLINE and Cochrane Library databases from inception to March 2014. Included studies were those that supplied zinc as supplements or measured dietary zinc intake. A meta-analysis of the extracted data was performed where sufficient data were available. Of all of the potentially relevant papers, 18 studies met the inclusion criteria, 12 of which were randomised controlled trials (RCTs; 11 in children and 1 in adults) and 6 were observational studies (2 in children and 4 in adults). Nine of the 18 studies reported a positive association between zinc intake or status with one or more measure of cognitive function. Meta-analysis of data from the adult’s studies was not possible because of limited number of studies. A meta-analysis of data from the six RCTs conducted in children revealed that there was no significant overall effect of zinc intake on any indices of cognitive function: intelligence, standard mean difference of <0.001 (95% confidence interval (CI) –0.12, 0.13) P=0.95; executive function, standard mean difference of 0.08 (95% CI, –0.06, 022) P=0.26; and motor skills standard mean difference of 0.11 (95% CI –0.17, 0.39) P=0.43. Heterogeneity in the study designs was a major limitation, hence only a small number (n=6) of studies could be included in the meta-analyses. Meta-analysis failed to show a significant effect of zinc supplementation on cognitive functioning in children though, taken as a whole, there were some small indicators of improvement on aspects of executive function and motor development following supplementation but high-quality RCTs are necessary to investigate this further

Tcf7l2 is required for left-right asymmetric differentiation of habenular neurons.

BACKGROUND: Although left-right asymmetries are common features of nervous systems, their developmental bases are largely unknown. In the zebrafish epithalamus, dorsal habenular neurons adopt medial (dHbm) and lateral (dHbl) subnuclear character at very different frequencies on the left and right sides. The left-sided parapineal promotes the elaboration of dHbl character in the left habenula, albeit by an unknown mechanism. Likewise, the genetic pathways acting within habenular neurons to control their asymmetric differentiated character are unknown. RESULTS: In a forward genetic screen for mutations that result in loss of habenular asymmetry, we identified two mutant alleles of tcf7l2, a gene that encodes a transcriptional regulator of Wnt signaling. In tcf7l2 mutants, most neurons on both sides differentiate with dHbl identity. Consequently, the habenulae develop symmetrically, with both sides adopting a pronounced leftward character. Tcf7l2 acts cell automously in nascent equipotential neurons, and on the right side, it promotes dHbm and suppresses dHbl differentiation. On the left, the parapineal prevents this Tcf7l2-dependent process, thereby promoting dHbl differentiation. CONCLUSIONS: Tcf7l2 is essential for lateralized fate selection by habenular neurons that can differentiate along two alternative pathways, thereby leading to major neural circuit asymmetries

A Synaptic Mechanism for Temporal Filtering of Visual Signals

The visual system transmits information about fast and slow changes in light intensity through separate neural pathways. We used in vivo imaging to investigate how bipolar cells transmit these signals to the inner retina. We found that the volume of the synaptic terminal is an intrinsic property that contributes to different temporal filters. Individual cells transmit through multiple terminals varying in size, but smaller terminals generate faster and larger calcium transients to trigger vesicle release with higher initial gain, followed by more profound adaptation. Smaller terminals transmitted higher stimulus frequencies more effectively. Modeling global calcium dynamics triggering vesicle release indicated that variations in the volume of presynaptic compartments contribute directly to all these differences in response dynamics. These results indicate how one neuron can transmit different temporal components in the visual signal through synaptic terminals of varying geometries with different adaptational properties

Cachd1 interacts with Wnt receptors and regulates neuronal asymmetry in the zebrafish brain.

Neurons on the left and right sides of the nervous system often show asymmetric properties, but how such differences arise is poorly understood. Genetic screening in zebrafish revealed that loss of function of the transmembrane protein Cachd1 resulted in right-sided habenula neurons adopting left-sided identity. Cachd1 is expressed in neuronal progenitors, functions downstream of asymmetric environmental signals, and influences timing of the normally asymmetric patterns of neurogenesis. Biochemical and structural analyses demonstrated that Cachd1 can bind simultaneously to Lrp6 and Frizzled family Wnt co-receptors. Consistent with this, lrp6 mutant zebrafish lose asymmetry in the habenulae, and epistasis experiments support a role for Cachd1 in modulating Wnt pathway activity in the brain. These studies identify Cachd1 as a conserved Wnt receptor-interacting protein that regulates lateralized neuronal identity in the zebrafish brain

Guideline for the treatment of myelodysplastic syndromes (MDS) in South Africa

The original publication is available at http://www.samj.org.zaIntroduction. Myelodysplastic syndromes (MDS) encompass a heterogeneous group of clonal haematopoietic disorders characterised by chronic and progressive cytopenias resulting from ineffective haematopoiesis. Treatment is complicated by differences in disease mechanisms in different subgroups, variable clinical phenotypes and risk of progression to acute myeloid leukaemia. Rationale. Changes in disease classification, prognostic scoring systems, the availability of novel treatment options and the absence of South African guidelines for the diagnosis and management of these complex disorders underpinned the need for the development of these recommendations. Methods. These recommendations are based on the opinion of a number of experts in the field from the laboratory as well as clinical settings and came from both the private and institutional academic environments. The most recent literature as well as available guidelines from other countries were discussed and debated at a number of different meetings held over a 2-year period. Results. A comprehensive set of recommendations was developed focusing on risk stratification, supportive management and specific treatment. Novel agents and their indications are discussed and recommendations are made based on best available evidence and taking into account the availability of treatments in South Africa. Conclusion. Correct diagnosis, risk stratification and appropriate therapeutic choices are the cornerstones of success in the management of patients with MDS.Publishers' Versio