Phytochemical Investigation and Anti-Microbial Activity of Clausena Anisata (Willd), Hook.

Background: Clausena anisata belongs to the family Rutaceae, a shrub widely used in West Africa for the treatment of bacterial and fungal infections of the skin including boils, ringworm and eczema. The study was designed to evaluate the antimicrobial activity and phytochemical screening of ethanol leaf extract of C. anisata (CLE).Method: Antimicrobial activity of CLE was investigated using agar well diffusion and micro-dilution methods against four Gram-positive bacteria (Bacillus substilis NCTC 10073, Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Bacillus thuringiensis ATCC 13838) and two Gram-negative bacteria (Pseudomonas aeruginosa ATCC 4853, Proteus vulgaris ATCC 4175) and a clinical isolate of Candida albicans.Results: CLE was active against all test organisms with minimum inhibitory concentration (MIC), range of 0.5 to 7.0 mg/mL against Gram-positive bacteria, 2.5 to 1.0 mg/mL against Gram-negative bacteria and 5.5mg/mL against C. albicans. The MICs of the methanol fraction of CLE were 0.6 mg to 5.0/mL and 1.0 to 3.0 mg/mL for Gram-positive and Gram-negative bacteria respectively. Chloroform fraction had MIC of 3.0 to 7.5 mg/mL and 2.0 to 6.5 mg/mL for Gram-positive and Gram-negative bacteria, respectively and petroleum ether fraction had 4.5 to 8.0 mg/mL for Gram-positive and Gram-negative bacteria. The CLE exhibited static action against all test organisms within a range of 0.5 to 22.0 mg/mL. Phytochemical screening of C. anisata revealed the presence of tannins, flavonoids, steroids, saponins, glycosides and alkaloids. HPLC finger-printing of the CLE and its fractions were determined.Conclusion: These results may justify the medicinal uses of C. anisata for the treatment of microbial infections.Keywords: Phytochemical screening, antibacterial, antifungal, static action

On-Site Effects and Cost of Fertility Erosion from Five Small Reservoir Catchments in the Upper East Region of Ghana

A study was carried out in the Upper East Region of Ghana to assess the on-site effects and the cost of fertility erosion from five small reservoir catchments (Dua, Doba, Zebilla, Kumpalgogo and Bugri). The catchment soils and reservoir sediments were sampled and analyzed for their bulk density and nutrient content. The mean reduction in soil depth in the various catchments was 3.996±3.806 mm y-1 in the order of Kumpalgogo>Dua>Bugri>Zebilla>Doba. The corresponding decrease in the water holding capacity of the top 20 cm depth of the catchment soils ranged from 0.563 to 4.698 % per year. The percentage loss in the total nutrient stocks in the top 20 cm of the catchments as eroded sediment-bound nutrients ranged from 9.63 to 64.71, 7.87 to 56.83, 6.12 to 54.82, 1.26 to 40.14, 49.86 to 12.65, 16.84 to 72.07 for OC, N, P, K, Ca and Mg, respectively. The total amount of nutrient loss in kg ha-1 among the reservoirs ranged from 2383 to 19672 for OC, 153 to 3048 for N, 3.15 to 42.59 for P, 41 to 290 for K, 432 to 2158 for Ca, and 63 to 483 for Mg. The cost of N, P and K removed by erosion was calculated by the Replacement Cost Method. The total cost per year (GH¢ ha-1 y-1) of fertilizers (sulphate of ammonia, single superphosphate and muriate of potash) was 286.15 for Dua, 74.289 for Doba, 225.061 for Zebilla, 1119.997 for Kumpalgogo and 96.376 for Bugri. The study has amply shown that soil loss through erosion reduces top soil depth, nutrient stocks and the water holding capacity of catchment soils. This will adversely affect crop productivity if no control measures are implemented. This can also lead to land degradation

Gametocyte Development and Carriage in Ghanaian Individuals with Uncomplicated Plasmodium falciparum Malaria.

Plasmodium falciparum gametocytes develop over 9-12 days while sequestered in deep tissues. On emergence into the bloodstream, they circulate for varied amounts of time during which certain host factors might influence their further development. We aimed to evaluate the potential association of patient clinical parameters with gametocyte development and carriage via in vivo methods. Seventy-two patients were enrolled from three hospitals in the Volta region of Ghana in 2016. Clinical parameters were documented for all patients, and gametocyte prevalence by microscopy was estimated at 12.5%. By measuring RNA transcripts representing two distinct gametocyte developmental stages using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR), we obtained a more precise estimate of gametocyte carriage while also inferring gametocyte maturation. Fifty-three percent of the study participants harbored parasites expressing transcripts of the immature gametocyte-specific gene (PF3D7_1477700), whereas 36% harbored PF3D7_1438800 RNA-positive parasites, which is enriched in mid and mature gametocytes, suggesting the presence of more immature stages. Linear logistic regression showed that patients older than 5 years but less than 16 years were more likely to carry gametocytes expressing both PF3D7_1477700 and PF3D7_1438800 compared with younger participants, and gametocytemia was more likely in mildly anemic individuals compared with those with severe/moderate anemia. These data provide further evidence that a greater number of malaria patients harbor gametocytes than typically estimated by microscopy and suggest a possible association between age, fever, anemia, and gametocytemia

A meta-analysis of long-term effects of conservation agriculture on maize grain yield under rain-fed conditions

Conservation agriculture involves reduced tillage, permanent soil cover and crop rotations to enhance soil fertility and to supply food from a dwindling land resource. Recently, conservation agriculture has been promoted in Southern Africa, mainly for maize-based farming systems. However, maize yields under rain-fed conditions are often variable. There is therefore a need to identify factors that influence crop yield under conservation agriculture and rain-fed conditions. Here, we studied maize grain yield data from experiments lasting 5 years and more under rain-fed conditions. We assessed the effect of long-term tillage and residue retention on maize grain yield under contrasting soil textures, nitrogen input and climate. Yield variability was measured by stability analysis. Our results show an increase in maize yield over time with conservation agriculture practices that include rotation and high input use in low rainfall areas. But we observed no difference in system stability under those conditions. We observed a strong relationship between maize grain yield and annual rainfall. Our meta-analysis gave the following findings: (1) 92% of the data show that mulch cover in high rainfall areas leads to lower yields due to waterlogging; (2) 85% of data show that soil texture is important in the temporal development of conservation agriculture effects, improved yields are likely on well-drained soils; (3) 73% of the data show that conservation agriculture practices require high inputs especially N for improved yield; (4) 63% of data show that increased yields are obtained with rotation but calculations often do not include the variations in rainfall within and between seasons; (5) 56% of the data show that reduced tillage with no mulch cover leads to lower yields in semi-arid areas; and (6) when adequate fertiliser is available, rainfall is the most important determinant of yield in southern Africa. It is clear from our results that conservation agriculture needs to be targeted and adapted to specific biophysical conditions for improved impact

Assessment of Clinical Outcomes Among Children and Adolescents Hospitalized With COVID-19 in 6 Sub-Saharan African Countries

Importance: Little is known about COVID-19 outcomes among children and adolescents in sub-Saharan Africa, where preexisting comorbidities are prevalent. / Objective: To assess the clinical outcomes and factors associated with outcomes among children and adolescents hospitalized with COVID-19 in 6 countries in sub-Saharan Africa. / Design, Setting, and Participants: This cohort study was a retrospective record review of data from 25 hospitals in the Democratic Republic of the Congo, Ghana, Kenya, Nigeria, South Africa, and Uganda from March 1 to December 31, 2020, and included 469 hospitalized patients aged 0 to 19 years with SARS-CoV-2 infection. / Exposures: Age, sex, preexisting comorbidities, and region of residence. / Main Outcomes and Measures: An ordinal primary outcome scale was used comprising 5 categories: (1) hospitalization without oxygen supplementation, (2) hospitalization with oxygen supplementation, (3) ICU admission, (4) invasive mechanical ventilation, and (5) death. The secondary outcome was length of hospital stay. / Results: Among 469 hospitalized children and adolescents, the median age was 5.9 years (IQR, 1.6-11.1 years); 245 patients (52.4%) were male, and 115 (24.5%) had comorbidities. A total of 39 patients (8.3%) were from central Africa, 172 (36.7%) from eastern Africa, 208 (44.3%) from southern Africa, and 50 (10.7%) from western Africa. Eighteen patients had suspected (n = 6) or confirmed (n = 12) multisystem inflammatory syndrome in children. Thirty-nine patients (8.3%) died, including 22 of 69 patients (31.9%) who required intensive care unit admission and 4 of 18 patients (22.2%) with suspected or confirmed multisystem inflammatory syndrome in children. Among 468 patients, 418 (89.3%) were discharged, and 16 (3.4%) remained hospitalized. The likelihood of outcomes with higher vs lower severity among children younger than 1 year expressed as adjusted odds ratio (aOR) was 4.89 (95% CI, 1.44-16.61) times higher than that of adolescents aged 15 to 19 years. The presence of hypertension (aOR, 5.91; 95% CI, 1.89-18.50), chronic lung disease (aOR, 2.97; 95% CI, 1.65-5.37), or a hematological disorder (aOR, 3.10; 95% CI, 1.04-9.24) was associated with severe outcomes. Age younger than 1 year (adjusted subdistribution hazard ratio [asHR], 0.48; 95% CI, 0.27-0.87), the presence of 1 comorbidity (asHR, 0.54; 95% CI, 0.40-0.72), and the presence of 2 or more comorbidities (asHR, 0.26; 95% CI, 0.18-0.38) were associated with reduced rates of hospital discharge. / Conclusions and Relevance: In this cohort study of children and adolescents hospitalized with COVID-19 in sub-Saharan Africa, high rates of morbidity and mortality were observed among infants and patients with noncommunicable disease comorbidities, suggesting that COVID-19 vaccination and therapeutic interventions are needed for young populations in this region

Using social reproduction theory to understand unfree labour

Most scholarship within social reproduction theory focuses on women’s paid and unpaid care and domestic work, typically within the global North. Rarely has social reproduction theory grappled with unfree labour in commodity supply chains, particularly in the global South. However, these labour relations also involve gendered power relations that cut across the productive and reproductive realms of the economy, which can be illuminated by social reproduction theory analysis. In this article, we reflect on how social reproduction theory can be used to make sense of unfree labour’s role in global supply chains, expanding its geographical scope and the forms of labour exploitation encompassed within it. Conceptually, we harness the insights of social reproduction theory, and Jeffrey Harrod and Robert W Cox’s work on ‘unprotected work’ in the global economy to examine how gendered power relations shape patterns of unfree labour. Empirically, we analyse interview and survey data collected among cocoa workers in Ghana through LeBaron’s Global Business of Forced Labour project. We argue that social reproduction theory can move global supply chain scholarship beyond its presently economistic emphasis on the productive sphere and can shed light into the overlaps between social oppression, economic exploitation, and social reproduction

Mouse models of neurodegenerative disease: preclinical imaging and neurovascular component.

Neurodegenerative diseases represent great challenges for basic science and clinical medicine because of their prevalence, pathologies, lack of mechanism-based treatments, and impacts on individuals. Translational research might contribute to the study of neurodegenerative diseases. The mouse has become a key model for studying disease mechanisms that might recapitulate in part some aspects of the corresponding human diseases. Neurode- generative disorders are very complicated and multifacto- rial. This has to be taken in account when testing drugs. Most of the drugs screening in mice are very di cult to be interpretated and often useless. Mouse models could be condiderated a ‘pathway models’, rather than as models for the whole complicated construct that makes a human disease. Non-invasive in vivo imaging in mice has gained increasing interest in preclinical research in the last years thanks to the availability of high-resolution single-photon emission computed tomography (SPECT), positron emission tomography (PET), high eld Magnetic resonance, Optical Imaging scanners and of highly speci c contrast agents. Behavioral test are useful tool to characterize di erent ani- mal models of neurodegenerative pathology. Furthermore, many authors have observed vascular pathological features associated to the di erent neurodegenerative disorders. Aim of this review is to focus on the di erent existing animal models of neurodegenerative disorders, describe behavioral tests and preclinical imaging techniques used for diagnose and describe the vascular pathological features associated to these diseases

Sediment-bound nutrient export from five small reservoir catchments and its implications for the Sudan savanna zone of Ghana

A study was carried out in the Sudan savanna zone in the Upper East Region of Ghana to assess the rate of sediment-bound nutrient export (NE) into five small reservoirs (Dua, Doba, Zebilla, Kumpalgogo and Bugri) and to analyse the implications of this export. The catchment soils and reservoir sediments from the various study sites were sampled and analysed for their bulk density, particle size distribution and nutrient content. Assessment of the nutrient concentrations indicated that the reservoir sediments were richer not only in nutrients and organic carbon, but also in clay and silt, than the catchment soils, having enrichment ratios >1. Nutrient export rates (NE; kg ha?1 year?1) from the reservoir catchments ranged from 0.755 (±0.264) for OC, 0.104 (±0.0245) for N, 0.0020 (±0.0003) for P, 0.016 (±0.0038) for K, 0.009 (±0.0024) for Na, 0.113 (±0.017) for Ca and 0.027 (±0.0093) for Mg. These rates were lower than those of other studies, likely due to the low nutrient content in the catchment soils. The relationships established between NE and specific sediment yield (SSY) indicated the NE was positively correlated with SSY (R2 = 0.66–0.98). The derived empirical equations can be satisfactorily used to predict the quantity of sediment-bound plant nutrients lost from similar catchments and subsequently stored in the reservoir sediments. The study results also suggest the need for sustainable land management practices to forestall erosion in the catchment areas and to reduce reservoir sedimentation, for enhancement of the livelihoods of the communities in the study area