Role of Cytokines in Trypanosoma brucei-Induced Anaemia: A Review of the Literature

Background: Anaemia is an important complication of trypanosomiasis. The mechanisms through which trypanosomal infection leads to anaemia are poorly defined. A number of studies have implicated inflammatory cytokines, but these data are limited and inconsistent. In this article, we reviewed the published literature on cytokines associated with Trypanosoma brucei infections and their role in the immunopathology leading to anaemia.Methodology: Articles were searched in PubMed through screening of titles and abstracts with no limitation on date of publishing and study design. Articles in English were searched using keywords “African trypanosomiasis”, “sleeping sickness”, “Trypanosoma brucei”, in all possible combinations with “anaemia” and/or “cytokines”.Results: Twelve articles examining cytokines and their role in trypanosomeinduced anaemia were identified out of 1095 originally retrieved from PubMed. None of the articles identified were from human-based studies. A total of eight cytokines were implicated, with four cytokines (IFN-γ, IL-10, TNF-α, IL-12) showing an association with anaemia. These articles reported that mice lacking TNF-α were able to control anaemia, and that IFN-γ was linked to severe anaemia given its capacity to suppress erythropoiesis, while IL-10 was shown to regulate IFN-γ and TNF-α, providing a balance that was associated with severity of anaemia. IFN-γ and TNF-α have also been reported to work in concert with other factors such as nitric oxide and iron in order to induce anaemia.Conclusion: IFN-γ, IL-10, and TNF-α were the three major cytokines identified to beheavily involved in anaemia caused by Trypanosoma brucei infection. The anti-inflammatory cytokine, IL-10, was shown to counter the effects of proinflammatory cytokines in order to balance the severity of anaemia. The mechanism of anaemia is multifactorial and therefore requires further, more elaborate research. Data from human subjects would also shed more light

Effect of substituting animal protein sources with soybean meal in diets of Oreochromis karongae (Trewavas 1941)

Three diets were formulated using locally available feed ingredients in Malawi to test the effect of replacing animal protein (fish meal, meat and bone meal) with soybean meal (10:0, 5:5, 0:10% of diet) as the protein source on growth and feed conversion of Oreochromis karongae. There were no significant differences in growth rate (GR), specific growth rate (SGR) and feed conversion ratios (FCR) among the three diets. It can be concluded that more expensive and limited animal protein sources can totally be replaced by cheaper soybean in order to get similar growth rates in O. karongae

Strengthening integration of chronic care in Africa: protocol for the qualitative process evaluation of integrated HIV, diabetes and hypertension care in a cluster randomised controlled trial in Tanzania and Uganda.

INTRODUCTION: In sub-Saharan Africa, the burden of non-communicable diseases (NCDs), particularly diabetes mellitus (DM) and hypertension, has increased rapidly in recent years, although HIV infection remains a leading cause of death among young-middle-aged adults. Health service coverage for NCDs remains very low in contrast to HIV, despite the increasing prevalence of comorbidity of NCDs with HIV. There is an urgent need to expand healthcare capacity to provide integrated services to address these chronic conditions. METHODS AND ANALYSIS: This protocol describes procedures for a qualitative process evaluation of INTE-AFRICA, a cluster randomised trial comparing integrated health service provision for HIV infection, DM and hypertension, to the current stand-alone vertical care. Interviews, focus group discussions and observations of consultations and other care processes in two clinics (in Tanzania, Uganda) will be used to explore the experiences of stakeholders. These stakeholders will include health service users, policy-makers, healthcare providers, community leaders and members, researchers, non-governmental and international organisations. The exploration will be carried out during the implementation of the project, alongside an understanding of the impact of broader structural and contextual factors. ETHICS AND DISSEMINATION: Ethical approval was granted by the Liverpool School of Tropical Medicine (UK), the National Institute of Medical Research (Tanzania) and TASO Research Ethics Committee (Uganda) in 2020. The evaluation will provide the opportunity to document the implementation of integration over several timepoints (6, 12 and 18 months) and refine integrated service provision prior to scale up. This synergistic approach to evaluate, understand and respond will support service integration and inform monitoring, policy and practice development efforts to involve and educate communities in Tanzania and Uganda. It will create a model of care and a platform of good practices and lessons learnt for other countries implementing integrated and decentralised community health services. TRIAL REGISTRATION NUMBER: ISRCTN43896688; Pre-results

Malaria and pregnancy: placental cytokine expression and its relationship to intrauterine growth retardation

Malaria infections during pregnancy can lead to the delivery of low-birth-weight infants. In this study, cytokine mRNA was measured in placentas from 23 malaria-infected and 21 uninfected primigravid women who had delivered in Mangochi, Malawi, a region with a high rate of transmission of falciparum malaria. Significantly increased expression of interleukin (IL)-1beta, IL-8, and tumor necrosis factor (TNF)-alpha and decreased expression of IL-6 and transforming growth factor-beta1 were found in malaria-infected compared with uninfected placentas. TNF-alpha and IL-8 were produced by maternally derived hemozoin-laden placental macrophages. Increased TNF-alpha expression was associated with increased placental hemozoin concentrations. Increased TNF-alpha or IL-8 expression in the placenta was associated with intrauterine growth retardation but not with preterm delivery. The results suggest that malaria infections induce a potentially harmful proinflammatory response in the placenta

Facility HIV Self-Testing in Outpatient Departments: An Assessment of Characteristics and Concerns of Outpatients Who Opt Out of Testing in Malawi

BackgroundFacility HIV self-testing (HIVST) in outpatient departments can dramatically increase testing among adult outpatients. However, it is still unclear why populations opt out of facility HIVST and reasons for opt outing. Using data from a parent facility HIVST trial, we sought to understand individual characteristics associated with opting out of facility HIVST and reported reasons for not testing.MethodsExit surveys were conducted with outpatients aged ≥15 years at 5 facilities in Central and Southern Malawi randomized to the facility HIVST arm of the parent trial. Outpatients were eligible for our substudy if they were offered HIVST and eligible for HIV testing (ie, never previously tested HIV positive and tested ≥12 months ago or never tested). Summary statistics and multivariate regression models were used.ResultsSeven hundred seventy-one outpatients were included in the substudy. Two hundred sixty-three (34%) opted out of HIVST. Urban residency (adjusted risk ratios [aRR] 3.48; 95% CI: 1.56 to 7.76) and self-reported poor health (aRR 1.86; 95% CI: 1.27 to 2.72) were associated with an increased risk of opting out. Male participants had a 69% higher risk of opting out (aRR 1.69; 95% CI: 1.14 to 2.51), with risk being 38% lower among working male participants. Primary reasons for not testing were feeling unprepared to test (49·4%) and perceived low risk of HIV infection (30·4%)-only 2.6% believed that HIVST instructions were unclear, and 1.7% were concerned about privacy.ConclusionWorking, risky sexual behavior, rural residence, and good self-rated health were positively associated with opting out of HIVST among outpatients. Strategies to address internalized barriers, such as preparedness to test and perceived need to test, should be incorporated into facility HIVST interventions

Sequential Acquisition of T Cells and Antibodies to Nontyphoidal Salmonella in Malawian Children

Background Salmonella Typhimurium (STm) remain a prominent cause of bacteremia in sub-Saharan Africa. Complement-fixing antibodies to STm develop by 2 years of age. We hypothesized that STm-specific CD4+ T cells develop alongside this process. Methods Eighty healthy Malawian children aged 0–60 months were recruited. STm-specific CD4+ T cells producing interferon γ, tumor necrosis factor α, and interleukin 2 were quantified using intracellular cytokine staining. Antibodies to STm were measured by serum bactericidal activity (SBA) assay, and anti-STm immunoglobulin G antibodies by enzyme-linked immunosorbent assay. Results Between 2006 and 2011, STm bacteremias were detected in 449 children <5 years old. STm-specific CD4+ T cells were acquired in infancy, peaked at 14 months, and then declined. STm-specific SBA was detectable in newborns, declined in the first 8 months, and then increased to a peak at age 35 months. Acquisition of SBA correlated with acquisition of anti–STm–lipopolysaccharide (LPS) immunoglobulin G (r = 0.329 [95% confidence interval, .552–.062]; P = .01) but not anti–STm–outer membrane protein or anti–STm-flagellar protein (FliC). Conclusions Acquisition of STm-specific CD4+ T cells in early childhood is consistent with early exposure to STm or cross-reactive protein antigens priming this T-cell development. STm-specific CD4+ T cells seem insufficient to protect against invasive nontyphoidal Salmonella disease, but sequential acquisition of SBA to STm LPS is associated with a decline in its incidence

High-power operation of coherently coupled tapered laser diodes in an external cavity

We demonstrate a rear-side phase-locking architecture with two high-brightness diode lasers. This technique is based on the passive phase-locking of emitters in an external cavity on their rear facet, and their coherent combination on the front facet. Two high-brightness high-power tapered laser diodes are coherently combined using a Michelson-based cavity. The combining efficiency is above 80% and results in an output power of 6.7 W in a nearly diffraction-limited beam. The rear-side architecture is then used with a laser bar of 5 tapered emitters using an interferometric extended cavity, based on a diffractive optical element. We describe the experimental evaluation of the diffractive optical element, and the phase-locked operation of the laser bar

Intracellular survival of Streptococcus pneumoniae in human alveolar macrophages is augmented with HIV infection

People Living with HIV (PLHIV) are at an increased risk of pneumococcal pneumonia than HIV-uninfected adults, but the reasons for this are still not well understood. We investigated whether alveolar macrophages (AM) mediated control of pneumococcal infection is impaired in PLHIV compared to HIV-uninfected adults. We assessed anti-bactericidal activity against Streptococcus pneumoniae of primary human AM obtained from PLHIV and HIV-uninfected adults. We found that pneumococcus survived intracellularly in AMs at least 24 hours post ex vivo infection, and this was more frequent in PLHIV than HIV-uninfected adults. Corroborating these findings, in vivo evidence showed that PLHIV had a higher propensity for harboring S. pneumoniae within their AMs than HIV-uninfected adults. Moreover, bacterial intracellular survival in AMs was associated with extracellular propagation of pneumococcal infection. Our data suggest that failure of AMs to eliminate S. pneumoniae intracellularly could contribute to the increased risk of pneumococcal pneumonia in PLHIV

SARS-CoV-2 testing and infection control strategies in European paediatric emergency departments during the first wave of the pandemic.

Between February and May 2020, during the first wave of the COVID-19 pandemic, paediatric emergency departments in 12 European countries were prospectively surveyed on their implementation of SARS-CoV-2 disease (COVID-19) testing and infection control strategies. All participating departments (23) implemented standardised case definitions, testing guidelines, early triage and infection control strategies early in the outbreak. Patient testing criteria initially focused on suspect cases and later began to include screening, mainly for hospital admissions. Long turnaround times for test results likely put additional strain on healthcare resources.Conclusion: Shortening turnaround times for SARS-CoV-2 tests should be a priority. Specific paediatric testing criteria are needed. What is Known: • WHO and public health authorities issued case definitions, testing and infection control recommendations for COVID-19 in January. • SARS-CoV-2 testing was made available across Europe in February. What is New: • Paediatric emergency departments implemented COVID-19-specific procedures rapidly, including case definitions, testing guidelines and early triage. • A third of surveyed departments waited more than 24 h for SARS-CoV-2 test to be reported, resulting in additional strain on resources