Yam Tuber Dormancy and Sprouting: The Role of Concentration Dynamics of Endogenous Gibberellic Acid

The role of endogenous gibberellic acid (GA ) in the regulation of yam (Dioscorea spp.) tuber 3 dormancy was investigated by determining the changes in the endogenous GA levels during 3 natural dormancy progression. Two Dioscorea rotundata cultivars ('Pona' and 'Labreko') and one Dioscorea alata cultivar ('CRI-Ahoɔdenfoɔ') used in these studies have varying dormancy duration. Endogenous GA levels determined for the yam tubers ranged from 1.53 – 3.05 mg/g dw 3 and 1.23 – 1.58 mg/g dw for 'Pona'; 1.53 – 3.40 mg/g dw and 1.25–1.57 mg/g dw for 'Labreko'; 1.48 – 3.62 mg/g dw and 1.28 – 1.60 mg/g dw for 'CRI-Ahoɔdenfoɔ', respectively, for the outer and inner portions. 'Pona' and 'Labreko' had dormancy break at 60 days after harvest (DAH), but at 90 DAH for 'CRI-Ahoɔdenfoɔ'. Generally, GA levels increased from harvest to the maximum 3 at 30 DAH, then declined to the minimum at 60 DAH before finally increasing again at 90 DAH for the outer portions of the yam tuber. For the inner portions of the tuber, GA levels rather 3 declined significantly to the minimum at 30 DAH, increased at 60 DAH and then decreased again at 90 DAH. GA levels in the outer portions of the tubers increased by 84-122%, 65-77% and 61- 3 65%, respectively, in 'CRI-Ahoɔdenfoɔ', 'Labreko' and 'Pona', but decreased in the inner portions by 19-23%, 24-26% and 26-28%. Essentially, higher amounts of endogenous gibberellins in yam tubers induced longer dormancy duration whereas lower amounts were indicative of dormancy termination and subsequent initiation of sprouting.&nbsp

Barriers to Buruli ulcer treatment completion in the Ashanti and Central Regions, Ghana.

BACKGROUND: Buruli ulcer is a chronic ulcerating skin condition, with the highest burden found in Central and West Africa where it disproportionately affects the most vulnerable populations. Treatment is demanding, comprising eight-weeks of daily antibiotics, regular wound care and possible surgical intervention. Treatment completion is key to optimising outcomes, however the degree of and barriers to this are not well understood. Recent change from injectable treatment (SR8) to oral treatment (CR8) has made it feasible to further decentralise care, potentially improving treatment access and completion. However, the impact of this and of other demographic and clinical influences on treatment completion must be explored first to ensure appropriate models of care are developed. METHODOLOGY/PRINCIPAL FINDINGS: A retrospective clinical notes review and secondary data analysis of records from patients diagnosed between 1 January 2006-31 December 2018 at four district hospital clinics in the Ashanti and Central Regions, Ghana. Univariable analyses and multivariable logistic regression were performed to assess the association between explanatory variables and treatment completion. There were 931 patient episodes across the four clinics with overall treatment completion of 84.4%. CR8 was associated with higher treatment completion compared to SR8 (OR 4.1, P = 0.001). There was no statistically significant association found between distance from patient residence to clinic and treatment completion. CONCLUSIONS/SIGNIFICANCE: Improved treatment completion with CR8 supports its use as first line therapy and may enable decentralisation to fully community-based care. We did not find an association between distance to care and treatment completion, though analyses were limited by data availability. However, we did find evidence that distance to care continues to be associated with more severe forms of disease, which may reflect the higher costs of accessing care and lower awareness of the condition the further a patient lives. Decentralised care must therefore also continue to support community engagement and active outreach to identify cases early

Intermittent Screening and Treatment versus Intermittent Preventive Treatment of Malaria in Pregnancy: Provider Knowledge and Acceptability

Malaria in pregnancy (MiP) is associated with increased risks of maternal and foetal complications. The WHO recommends a package of interventions including intermittent preventive treatment (IPT) with sulphadoxine-pyrimethamine (SP), insecticide-treated nets and effective case management. However, with increasing SP resistance, the effectiveness of SP-IPT has been questioned. Intermittent screening and treatment (IST) has recently been shown in Ghana to be as efficacious as SP-IPT. This study investigates two important requirements for effective delivery of IST and SP-IPT: antenatal care (ANC) provider knowledge, and acceptance of the different strategies. Structured interviews with 134 ANC providers at 67 public health facilities in Ashanti Region, Ghana collected information on knowledge of the risks and preventative and curative interventions against MiP. Composite indicators of knowledge of SP-IPT, and case management of MiP were developed. Log binomial regression of predictors of provider knowledge was explored. Qualitative data were collected through in-depth interviews with fourteen ANC providers with some knowledge of IST to gain an indication of the factors influencing acceptance of the IST approach. 88.1% of providers knew all elements of the SP-IPT policy, compared to 20.1% and 41.8% who knew the treatment policy for malaria in the first or second/third trimesters, respectively. Workshop attendance was a univariate predictor of each knowledge indicator. Qualitative findings suggest preference for prevention over cure, and increased workload may be barriers to IST implementation. However, a change in strategy in the face of SP resistance is likely to be supported; health of pregnant women is a strong motivation for ANC provider practice. If IST was to be introduced as part of routine ANC activities, attention would need to be given to improving the knowledge and practices of ANC staff in relation to appropriate treatment of MiP. Health worker support for any MiP intervention delivered through ANC clinics is critical

Overview of preparedness and response to COVID-19 in Ghana

The Coronavirus disease 2019 (COVID-19) outbreak in Ghana is part of an ongoing pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The first two cases of COVID-19 were confirmed in Ghana on 12th March 2020. COVID-19 was consequently declared a Public Health Emergency of National Concern, triggering several response actions, including enhanced surveillance, case detection, case management and contact tracing, closure of borders, suspension of international flights, ban on social gatherings and closure of schools. Preparedness and response plans were activated for implementation at the national, regional, district and community levels. Ghana’s Strategic approaches were to limit and stop the importation of cases; detect and contain cases early; expand infrastructure, logistics and capacity to provide quality healthcare for the sick; minimise disruption to social and economic life and increase the domestic capacity of all sectors to deal with existing and future shocks. The health sector strategic frame focused on testing, treatment, and tracking. As of 31st December 2020, a total of 535,168 cases, including 335 deaths (CFR: 0.61%), have been confirmed with 53,928 recoveries and 905 active cases. All the regions have reported cases, with Greater Accra reporting the highest number. The response actions in Ghana have seen highlevel political commitment, appropriate and timely decisions, and a careful balance of public health interventions with economic and socio-cultural dynamics. Efforts are ongoing to intensify non-pharmaceutical interventions, sustain the gains made so far and introduce COVID-19 vaccines to reduce the public health burden of the disease in Ghan

Diagnostics for COVID-19: A case for field-deployable, rapid molecular tests for community surveillance

Across the globe, the outbreak of the COVID-19 pandemic is causing distress with governments doing everything in their power to contain the spread of the novel coronavirus (SARS-CoV-2) to prevent morbidity and mortality. Actions are being implemented to keep health care systems from being overstretched and to curb the outbreak. Any policy responses aimed at slowing down the spread of the virus and mitigating its immediate effects on health care systems require a firm basis of information about the absolute number of currently infected people, growth rates, and locations/hotspots of infections. The only way to obtain this base of information is by conducting numerous tests in a targeted way. Currently, in Ghana, there is a centralized testing approach, that takes 4-5 days for samples to be shipped and tested at central reference laboratories with results communicated to the district, regional and nationalstakeholders. This delay in diagnosis increases the risk of ongoing transmission in communities and vulnerable institutions. We have validated, evaluated and deployed an innovative diagnostic tool on a mobile laboratory platform to accelerate the COVID-19 testing. A preliminary result of 74 samples from COVID-19 suspected cases has a positivity rate of 12% with a turn-around time of fewer than 3 hours from sample taking to reporting of results, significantly reducing the waiting time from days to hours, enabling expedient response by the health system for contact tracing to reduce transmission and additionally improving case management

Improvement of Rice Production under Drought Conditions in West Africa: Application of QTLs in Breeding for Drought Resistance

Rice plays a paramount role in food and nutrition security in many West African countries. Despite the doubling of production during the last decade, rice consumption has grown faster, creating a deficit between the demand and supply. Although the West African sub-region remains the main rice-producing centre on the continent, production is severely hampered by biotic and abiotic stresses. Drought is one of the factors that most severely reduce grain yields of rice. Systems of production need to be established in order to mitigate yield loss as a result of drought. This review discusses the effects of drought on rice production in West Africa and its mitigation with an emphasis on the improvement of tolerance to drought stress. Yield stability can be achieved by developing drought-tolerant varieties through several processes encompassing profiling of known QTLs and identification of new ones, marker-assisted selection, genomic selection, and extensive multi-locational yield trials. We suggest a comprehensive strategy for breeding drought-tolerant rice varieties in West Africa

Mycolactone Diffuses into the Peripheral Blood of Buruli Ulcer Patients - Implications for Diagnosis and Disease Monitoring.

BACKGROUND: Mycobacterium ulcerans, the causative agent of Buruli ulcer (BU), is unique among human pathogens in its capacity to produce a polyketide-derived macrolide called mycolactone, making this molecule an attractive candidate target for diagnosis and disease monitoring. Whether mycolactone diffuses from ulcerated lesions in clinically accessible samples and is modulated by antibiotic therapy remained to be established. METHODOLOGY/PRINCIPAL FINDING: Peripheral blood and ulcer exudates were sampled from patients at various stages of antibiotic therapy in Ghana and Ivory Coast. Total lipids were extracted from serum, white cell pellets and ulcer exudates with organic solvents. The presence of mycolactone in these extracts was then analyzed by a recently published, field-friendly method using thin layer chromatography and fluorescence detection. This approach did not allow us to detect mycolactone accurately, because of a high background due to co-extracted human lipids. We thus used a previously established approach based on high performance liquid chromatography coupled to mass spectrometry. By this means, we could identify structurally intact mycolactone in ulcer exudates and serum of patients, and evaluate the impact of antibiotic treatment on the concentration of mycolactone. CONCLUSIONS/SIGNIFICANCE: Our study provides the proof of concept that assays based on mycolactone detection in serum and ulcer exudates can form the basis of BU diagnostic tests. However, the identification of mycolactone required a technology that is not compatible with field conditions and point-of-care assays for mycolactone detection remain to be worked out. Notably, we found mycolactone in ulcer exudates harvested at the end of antibiotic therapy, suggesting that the toxin is eliminated by BU patients at a slow rate. Our results also indicated that mycolactone titres in the serum may reflect a positive response to antibiotics, a possibility that it will be interesting to examine further through longitudinal studies

Kinetics of mycolactone in human subcutaneous tissue during antibiotic therapy for Mycobacterium ulcerans disease.

BACKGROUND: Mycobacterium ulcerans (M. ulcerans) causes a devastating necrotising infection of skin tissue leading to progressive ulceration. M. ulcerans is the only human pathogen that secretes mycolactone, a polyketide molecule with potent cytotoxic and immunomodulatory properties. These unique features make mycolactone an attractive biomarker for M. ulcerans disease. We sought to measure the concentration of mycolactone within lesions of patients with Buruli ulcer before, during and after antibiotic treatment to evaluate its association with the clinical and bacteriological response to therapy. METHODS: Biopsies of M. ulcerans infected skin lesions were obtained from patients before, during and after antibiotic therapy. Lipids were extracted from the biopsies and concentration of mycolactone was assayed by mass spectrometry and a cytotoxicity assay and correlated with clinical and bacteriological response to therapy. RESULTS: Baseline concentration of mycolactone measured by mass spectrometry predicted time to complete healing of small nodules and ulcers. Even though intra-lesional concentrations of mycolactone declined with antibiotic treatment, the toxin was still present after antibiotic treatment for 6 weeks and also 4 weeks after the end of treatment for 8 weeks in a subgroup of patients with slowly healing lesions. Additionally viable bacilli were detected in a proportion of these slowly healing lesions during and after treatment. CONCLUSIONS: Our findings indicate that baseline intra-lesional mycolactone concentration and its kinetics with antibiotic therapy are important prognostic determinants of clinical and bacteriological response to antibiotic treatment for Mycobacterium ulcerans disease. Mycolactone may be a useful biomarker with potential utility in optimising antibiotic therapy

The Critical Need for Pooled Data on Coronavirus Disease 2019 in African Children: An AFREhealth Call for Action Through Multicountry Research Collaboration

Globally, there are prevailing knowledge gaps in the epidemiology, clinical manifestations, and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among children and adolescents; and these gaps are especially wide in African countries. The availability of robust age-disaggregated data is a critical first step in improving knowledge on disease burden and manifestations of coronavirus disease 2019 (COVID-19) among children. Furthermore, it is essential to improve understanding of SARS-CoV-2 interactions with comorbidities and coinfections such as human immunodeficiency virus (HIV), tuberculosis, malaria, sickle cell disease, and malnutrition, which are highly prevalent among children in sub-Saharan Africa. The African Forum for Research and Education in Health (AFREhealth) COVID-19 Research Collaboration on Children and Adolescents is conducting studies across Western, Central, Eastern, and Southern Africa to address existing knowledge gaps. This consortium is expected to generate key evidence to inform clinical practice and public health policy-making for COVID-19 while concurrently addressing other major diseases affecting children in African countries

Elevated rates of horizontal gene transfer in the industrialized human microbiome

Industrialization has impacted the human gut ecosystem, resulting in altered microbiome composition and diversity. Whether bacterial genomes may also adapt to the industrialization of their host populations remains largely unexplored. Here, we investigate the extent to which the rates and targets of horizontal gene transfer (HGT) vary across thousands of bacterial strains from 15 human populations spanning a range of industrialization. We show that HGTs have accumulated in the microbiome over recent host generations and that HGT occurs at high frequency within individuals. Comparison across human populations reveals that industrialized lifestyles are associated with higher HGT rates and that the functions of HGTs are related to the level of host industrialization. Our results suggest that gut bacteria continuously acquire new functionality based on host lifestyle and that high rates of HGT may be a recent development in human history linked to industrialization.Peer reviewe