Are Fc gamma receptor polymorphisms important in HIV-1 infection outcomes and latent reservoir size?

Fc gamma receptors (FcγR) are cell surface glycoproteins which trigger specific effector-cell responses when cross-linked with the Fc portions of immunoglobulin (IgG) antibodies. During HIV-1 infection, the course of disease progression, ART response, and viral reservoir size vary in different individuals. Several factors may account for these differences; however, Fc gamma receptor gene polymorphisms, which influence receptor binding to IgG antibodies, are likely to play a key role. FcγRIIa (CD32) was recently reported as a potential marker for latent HIV reservoir, however, this assertion is still inconclusive. Whether FcγR polymorphisms influence the size of the viral reservoir, remains an important question in HIV cure studies. In addition, potential cure or viral suppression methods such as broadly neutralizing antibody (bNAbs) may depend on FcγRs to control the virus. Here, we discuss the current evidence on the potential role played by FcγR polymorphisms in HIV-1 infection, treatment and vaccine trial outcomes. Importantly, we highlight contrasting findings that may be due to multiple factors and the relatively limited data from African populations. We recommend further studies especially in sub-Saharan Africa to confirm the role of FcγRIIa in the establishment of latent reservoir and to determine their influence in therapies involving bNAbs

Effect of Solvent Extraction Parameters on the Recovery of Oil From Spent Coffee Grounds for Biofuel Production

Spent coffee grounds (SCG) are a potentially valuable source of lipids for sustainable production of biofuels. However, there are several feedstock properties and solvent extraction parameters that can impact on the oil yield and quality, potentially reducing the possible environmental benefits of deriving oils from this waste stream. This study presents results of laboratory and pilot plant scale experimental investigations into lipid recovery from spent coffee, determining the effects of solvent extraction variables including duration, SCG-to-solvent ratio and SCG residual moisture. SCG samples from both the industrial production of instant coffee and retail coffee shops were characterized in terms of moisture content, particle size distribution and oil content to identify the impact of these variables on the efficiency of lipid recovery by solvent extraction. The dry weight oil content of the instant SCG samples ranged from 24.2 to 30.4% w/w, while the retail SCG samples contained considerably lower amounts of lipids with their oil content ranging between 13.4 and 14.8% w/w. The highest oil yields were found at an extraction duration of 8 h, while a moisture content of ~2% w/w led to increased yields relative to completely dry samples. A pattern of increasing acidity with decreasing extraction duration was observed, suggesting preferential extraction of free fatty acids (FFA), with the fatty acid (FA) profile of the oil found to be similar to lipids commonly utilized for biofuel production

COVID-19 pandemic: ten research questions Africa must answer for itself

The COVID-19 pandemic is spreading through Africa and governments are making frantic efforts to control spread, hospitalizations and deaths. While control measures are being taken, research into the biomedical and socio-cultural aspects of the pandemic, relevant to the African population, should not be ignored. It should not be assumed that research performed in Asian, American and European populations will always be applicable to Africa. Rather, research should be done in Africa to answer questions peculiar to the epidemic on the continent and help inform international guidelines. National guidelines for treatment and prevention, patient recoveries and discharge, and public health control measures should be based on research performed in the appropriate context for them to be effective and robust. Urgent research is needed in viral immunology and shedding, treatment and prevention trials, protection of healthcare personnel, and antimicrobial use among others. In this article, we propose ten research questions that when answered in a timely manner by scientists in Africa, will enhance Africa’s response to the pandemic

HIV cure strategies: Which ones are appropriate for Africa?

Although combination antiretroviral therapy (ART) has reduced mortality and improved lifespan for people living with HIV, it does not provide a cure. Patients must be on ART for the rest of their lives and contend with side effects, unsustainable costs, and the development of drug resistance. A cure for HIV is, therefore, warranted to avoid the limitations of the current therapy and restore full health. However, this cure is difficult to find due to the persistence of latently infected HIV cellular reservoirs during suppressive ART. Approaches to HIV cure being investigated include boosting the host immune system, genetic approaches to disable co-receptors and the viral genome, purging cells harboring latent HIV with latency-reversing latency agents (LRAs) (shock and kill), intensifying ART as a cure, preventing replication of latent proviruses (block and lock) and boosting T cell turnover to reduce HIV-1 reservoirs (rinse and replace). Since most people living with HIV are in Africa, methods being developed for a cure must be amenable to clinical trials and deployment on the continent. This review discusses the current approaches to HIV cure and comments on their appropriateness for Africa

Assessing arthropod pests and disease occurrence in cassava (Manihot esculenta Crantz) and cowpea (Vigna unguiculata L. Walp) intercropping system in the Ashanti Region, Ghana

On-station trials were conducted at CSIR-Crops Research Institute’s research farms at Kwadaso and Ejura, Ashanti Region, Ghana, during 2010/2011 cropping season, to assess the pests and disease occurrence in cassava-cowpea intercrop farming systems and their effect on yield of produce. Three improved cassava varieties and a local variety were intercropped with an improved cowpea variety, and cowpea only constituted the treatments. Abundance of Bemisia tabaci was comparable between sole cassava and cassava-cowpea intercrop, but was significantly less on the sole cowpea. The incidence and severity of cassava mosaic disease was higher on the local variety than on the improved varieties. Root yield of cassava did not differ between sole and intercropped cassava with cowpea. However, Kwadaso had higher root yield than Ejura. Dry grain yield of cowpea was similar at Kwadaso and Ejura for both sole and intercrop scenarios. This baseline information will be useful on disease and pests incidence in sole crop and cassava-cowpea intercropping system

The burden and characteristics of peripheral arterial disease in patients undergoing amputation in Korle Bu Teaching Hospital, Accra, Ghana

Background: To determine the prevalence of Peripheral Arterial Disease (PAD) and associated risk factors in patients undergoing amputation at the Korle Bu Teaching Hospital (KBTH), Accra, Ghana.Objectives: A cross- sectional study of all patients undergoing lower extremity amputation at the Department ofSurgery, KBTH.Materials: A coded questionnaire was used to ascertain risk factors for PAD. The Edinburgh Claudication Questionnaire was used to determine symptomatic PAD and a 5 mmHz hand held Summit® Doppler together with an Accoson® sphygmomanometer was used to determine PAD and its severity.Method: Clinical diagnosis of symptomatic PAD was made using a symptom-based questionnaire and signs of PAD determined by measuring the ankle brachial pressure index (ABPI) by means of a handheld Doppler and sphygmomanometer. Risk factors were determined using the coded questionnaire and related to the occurrence and severity of PAD.Results: The prevalence of PAD among recruited participants was 71%. Twenty-eight per cent of participants with PAD in the index limb also showed signs of PAD in the other limb. The diagnosis of PAD was made in 71%, using ABPI, and 13%, using ECQ. Twenty-seven per cent of patient with hypertension, seventeen per cent with diabetes and all patients with hypercholesterolemia were not on any form of medication.Conclusion: There is a high prevalence of PAD among patients undergoing lower extremity amputation at the KBTH. The majority of PAD patients presented with moderate to severe PAD. Instituting measures to identify and control risk factors of PAD may reduce this high burden.Funding: Not declaredKeywords: Peripheral arterial disease, ABPI, Prevalence, Ghana, AmputationFunding source: Authors funded the stud

An explorative study on the adoption and dis-adoption of improved rice varieties among farmers in the Northern region of Ghana

Rice consumption in Ghana has increased steadily over the years. To enhance rice productivity to meet demand, several high-performing rice varieties have been disseminated via numerous interventions to smallholders in Northern Ghana. Nevertheless, productivity is still low at farm gate compared to research stations, due to smallholder poor adoption of the varieties. Using primary data collected from 404 farmers, the study examines the adoption levels of the main rice varieties among farmers and investigates the reasons for their adoption and dis-adoption. The empirical results revealed that rice varieties namely, Agra, Sakai, Jasmine 85, and Afife were the most adopted in the study area. Also, the study finds that GR-18, Nerica, Digang, Tox, Mandee, and Faro-15 were the most dis-adopted rice varieties. The main reasons for which farmers adopted the improved rice varieties were availability of a ready market for the produce, crop resistance to pests and diseases, consumer higher demand for rice, advice by extension staff to cultivate, and encouragement from researchers to adopt. The reasons for the dis-adoption of improved rice varieties in the study area were high input requirements, lack of ready market for the varieties, and unfavorable climatic conditions. The findings of the study give direction as to the angle from which the adoption of improved rice varieties can be stepped up while dis-adoption is reduced. Research scientists should research into rice varieties that are more suitable for the soil and climatic conditions of the study area and continue to sensitize and motivate the farmers to adopt them, while government should step up its support for the research scientists as well as the extension officers to deliver on their mandate

GASTRO-DUODENAL PEPTIC ULCER PERFORATION

Objectives: To determine the epidemiology of, and define the morbidity and mortalityfactors following emergency surgery for patients with perforated peptic ulcer diseasein Accra, Ghana.Design: A retrospective and prospective hospital-based study.Setting: The general and paediatric surgical wards of the Korle-Bu TeachingHospital.Main outcome measures: Demography, the systolic BP, pulse rate and haemoglobinon admission at ER, co-morbid conditions, site of perforation, surgical method andtreatment outcome.Subjects: A total of 326 cases treated for peptic ulcer perforation, 267 males and 59 females;ratio 4.5:1, with mean age of 40.9, SD 16.4 and range 4-87 years, were studied.Results: The incidence of peptic ulcer perforation rose from 1.6% in 1998 to 5.3% in2002 and stabilised at 5%, and overall accounted for 4.6% of acute abdomen. Co-morbidconditions were present in 48 (18.2%) of cases. Ulcerogenic substance intake was in177 (67%) patients. One hundred and twenty two (46.2%) patients reported to hospitalwithin 24 hours of perforation. There were 287 (88%) duodenal, 22 (7.1%) prepyloric,and 19(4.9%) type 1 gastric ulcer perforations. Simple closure with omental patch wasperformed in 299(94.3%), truncal vagotomy and drainage in 10 (3.2%), and Billroth IIpartial gastrectomy in seven (2.2%). Post-operative complications occurred in 62 (19%);overall mortality was 36 (11%). Logistic regression analysis of the patients clinicalvariables showed that age less that 60 years (p-value, OR and 95% CI; 0.002, 3.964 and1 .668-9.420), duration of perforation of more than 24 hours before admission (p-value,OR and 95%CI; 0.011,2.471 and 1.228-4.971), alcohol intake (p-value, OR and 95%CI;0.009, 2.543 and 1.259-5.135) and resectional surgery (p-value, OR and 95%CI; 0.000,8.25E and 74204908.138-9162648048.1) were statistically significant in determining postoperativecomplications. Age 60 years and above (p-value, OR and 95%CI; 0.018,4.359and 1.284-14.802), alcohol intake (p-value, OR and 95%CI; 0.042, 3.238 and 1.046- 10.021)and resectional surgery (p-value, OR and 95% CI; 0.000, 1.20E and 938112920.94- 1.54E+11) were the factors that showed statistical significance in determining post-operativemortality.Conclusion: Perforated peptic ulcer disease is emerging as a frequent cause of acuteabdomen in our centre and affects the youth commonly. Age 60 years and above,duration of perforation for more than 24 hours before admission, alcohol intake andresectional surgery were the variables that showed statistical significance in predictingpost-operative morbidity and/or mortality

Transesterification of high-acidity spent coffee ground oil and subsequent combustion and emissions characteristics in a compression-ignition engine

Lipids extracted from spent coffee grounds (SCG) are a potentially promising feedstock for biodiesel production if the relatively high free fatty acid (FFA) portion of the oil can be successfully converted into methyl esters, and the resulting biodiesel found to have acceptable combustion and emissions performance. This study presents experimental results obtained from transesterification of SCG-extracted oil with a FFA content of ∼30% w/w through a two-step process, followed by fuel characterization and combustion experiments with SCG-derived biodiesel, pure and blended with fossil diesel, and untreated SCG oil in a single cylinder research compression-ignition engine. The acid-catalyzed pretreatment reduced the FFA content of the oil below 1.5% w/w, with minor losses, and showed the methanol-to-FFA molar ratio to be more significant relative to the quantity of sulphuric acid used as a catalyst within the range of investigated conditions, while the subsequent base-catalyzed step converted ∼87% of the pretreated oil into biodiesel with a higher heating value (HHV) of 39.7 MJ/kg. The combustion and emission characteristics of pure and blended SCG biodiesel revealed similarities with those of commercial rapeseed and soya biodiesel samples tested. While ignition delay decreased with increasing SCG biodiesel content, the comparatively higher CO, total hydrocarbon (THC) and particulate emissions of the SCG biodiesel were attributed to higher fuel kinematic viscosity (KV). Combustion of the untreated SCG oil produced low in-cylinder peak pressure and peak heat release relative to other samples tested despite a longer ignition delay, suggesting that the oil physical properties were more important in determining combustion performance

Influence of solvent selection and extraction temperature on yield and composition of lipids extracted from spent coffee grounds

Spent coffee grounds (SCG) are a potentially sustainable source of C16-C18 triglycerides. This study investigates known solvent extraction technologies with a wide range of solvents for lipid extraction from SCGs, and determines the effect of solvent selection and process temperature on the extraction efficiency and composition of the obtained oil. A correlation between increasing solvent boiling point, and therefore process temperature, and improved oil extraction efficiency was observed in Soxhlet extractions with a wide range of solvents. Experiments at elevated temperatures (up to 200 °C) were performed through Accelerated Solvent Extraction (ASE) and temperature increase initially improved the oil extraction efficiency when non-polar solvents were used, before decreasing it at higher temperatures. Utilization of ethanol resulted in the highest oil extraction ratio by ASE (at 165 °C), suggesting that temperature increase is more beneficial to the extraction efficiency of polar solvents. In addition, analysis of the oils was carried out to evaluate the composition of the oils extracted from SCGs using different solvents and extraction parameters. The Nuclear Magnetic Resonance (NMR) results were in agreement with the values obtained from the titrimetric determination of the free fatty acid content (FFA) of the oils in terms of the comparative trends, and also tentatively suggest that some differences in the composition of the extracted oils might be related to the type of extraction solvent used