Compensatory and susceptive responses of cowpea genotypes to infestation by aphis Craccivora koch.

The aim of the study was to estimate yield loss to10 selected genotypes of cowpea as a result of Aphis craccivora infestation during the vegetative phase of the crop. There were two trials with four replications. The first trial serving as the control was sprayed at the seedling, flowering andpodding stages against insect pests with lambda cyhalothrin (PAWA®). The other trial was sprayed only at flowering and podding stages. The cowpea seedlings of the second trial were infested with five four-day-old aphids per seedling two weeks after planting. The aphids were allowed to form colonies and fed on the seedlings until symptoms of damage were observed. When the susceptible seedlings became stunted with distorted leaves and yellowing of leaves at two weeks after infestation (28 days after planting), aphids were controlled. The results showed that aphids’ infestation delayed flowering and maturity of genotypes of cowpea. With the exception of early flowering genotypes all the medium to late flowering genotypes produced higher dry grain yield in infested plots than the control plots. The trend was not different from the production of dry biomass. The results of the present study implies that control of aphids infestation inearly maturing cowpea genotypes should not be delayed up to two weeks after infestation or 28 days after planting. Aphid’s infestation period for studies in susceptive response in medium to late maturing genotypes should go beyond 28 days after planting probably up to 35 days afterplanting

Changing Agricultural Practices and Indigenous Food Crops in the Upper Afram Basin of Ghana

The Forest Savanna Transition zone within which the Upper Afram basin lies, account for a wide variety of food crops and plant species. This study examined the effects of changing ag­ricultural practices on cultivation and availability of indigenous food crops within the basin. Qualitative data obtained from 240 farmers through individual interviews and Focus group dis­cussions were analyzed thematically. The study revealed that even though the farmers employed the traditional mixed cropping system, the widespread use of agro-chemicals in the study area was limiting the practice of intercropping. This accounts for the current dominance of mono cropping system in the study area. These changes have affected the cultivation of a wide variety of indigenous foods within the basin. The uncontrolled use of agro-chemicals constituted one of the major agronomic constraints affecting the cultivation of these crops. Adequate technical support services to effectively control agrochemical abuse among the local farmers will, there­fore, be required. Increased sensitization on the need for local farmers to refocus and maintain some of the traditional agricultural practices that ensured the cultivation of a wide variety of indigenous food crop varieties (NUCS) in their farms is also suggested

Suspended sediment transport into a water supply reservoir in southern Ghana

Weija reservoir on the Densu river serves as a source of water supply to parts of Greater Accra and Central regions of Ghana. The Densu river basin is characterised by accelerated land degradation. A number of Integrated Water Resources Management (IWRM) interventions have been implemented in the basin. Reports suggest there has been an improvement of physicochemical parameters of the water resources. However, there is no recent study on fluvial sediment transport in the basin. This paper assessed sediment transport into the Weija reservoir via the Densu River. Weekly suspended sediment concentration and river discharge were monitored over a 1 year period to quantify sediment yield into the reservoir. The results indicated that total annual suspended sediment yield, and annual specific suspended sediment yield were 5375 t yr-1 and 2.0 t km-2 yr-1, respectively. These were relatively low compared to results obtained by past studies on the Densu basin at upstream Mangoase (6146 t yr-1 and 2.49 t km-2 yr-1) and other river basins in Ghana. Parameters established from a yield rating curve indicated that parts of the basin were degraded and sediment transport in the basin was largely due to the availability of sediment in the catchment and not just due to high river discharges. The relatively low sediment transport at Weija may be indicative of the success of the IWRM interventions. It is recommended that these be sustained and/or intensified

Mycobacterial species causing pulmonary tuberculosis At the korle bu teaching hospital, Accra,

Objective: Characterize mycobacterial species causing pulmonary tuberculosis (PTB) at the Korle-Bu Teaching Hospital in Ghana.Design: Sputum smear positive samples, two (2) from 70 patients diagnosed as having tuberculosis, after they had consented, were collected from the Korle-Bu Teaching Hospital Chest Clinic betweenJanuary and July 2003. Setting: Korle-Bu Teaching Hospital Chest Clinic, Accra. Results: Sixty-four mycobacterial isolates wereobtained and confirmed as members of Mycobacterium tuberculosis complex by colonial morphology and conventional biochemical assays. Fortyseven (73%) were M. tuberculosis, the human strain, 2 (3%) M. bovis, the bovine strain, 13 (20%) M. africanum I (West Africa type), and 2 (3%) M. africanum II (East Africa type). Conclusion: The results indicate that, there are various strains causing PTB at the Korle-BuTeaching Hospital and of great concern is M. bovis, which mostly causes extra-PTB in humans but found to cause PTB in this study. This calls for the need to conduct a nationwide survey using bothconventional and molecular techniques to characterize various mycobacterial species causing TB in Ghana. This will result in better understanding of the various strains circulating in the country andinform individual TB treatment regimen especially the inclusion or exclusion of pyrazinamide

Climate and livelihood change in North East Ghana

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Assessing the Policy Landscape for Salt Reduction in South-East Asian and Latin American Countries – An Initiative Towards Developing an Easily Accessible, Integrated, Searchable Online Repository

BACKGROUND: High dietary salt intake is an avoidable cause of hypertension and associated cardiovascular diseases (CVDs). Thus, salt reduction is recommended as one of the most cost-effective interventions for CVD prevention and for achieving the World Health Organization’s (WHO) 25% reduction in premature non-communicable disease (NCD) mortality by 2025. However, current and comprehensive information about national salt reduction policies and related actions across different regions are difficult to access and impede progress and monitoring. OBJECTIVES: As an initial step to developing an online repository of salt reduction policies and related actions, and to track nation-wise progress towards the WHO’s 25 by 25 goal, we aimed to identify and assess salt reduction policies and actions in select countries from two of the top five most populous regions of the world- the South-East Asia and Latin America. METHODS: We conducted a literature review to identify national and regional salt reduction policies in the selected South-East Asian and Latin American countries, from January 1990–August 2020, available in English and Spanish. We also contacted selected WHO country offices (South-East Asian region) or relevant national authorities (Latin America) to gain access to unpublished documents. RESULTS: In both regions, we found only a few dedicated stand-alone salt reduction policies: Bhutan, Sri-Lanka and Thailand from South East Asia and Costa Rica from Latin America. Available polices were either embedded in other national health/nutritional policy documents/overall NCD policies or were unpublished and had to be accessed via personal communication. CONCLUSIONS: Salt reduction policies are limited and often embedded with other policies which may impede their implementation and utility for tracking national and international progress towards the global salt reduction target associated with the 25 by 25 goal. Developing an online repository could help countries address this gap and assist researchers/policymakers to monitor national progress towards achieving the salt reduction target

Elevated Circulating Angiogenic Progenitors and White Blood Cells Are Associated with Hypoxia-Inducible Angiogenic Growth Factors in Children with Sickle Cell Disease

We studied the number and function of angiogenic progenitor cells and growth factors in children aged 5–18 years without acute illness, 43 with Hemoglobin SS and 68 with normal hemoglobin. Hemoglobin SS subjects had at least twice as many mononuclear cell colonies and more circulating progenitor cell than Control subjects. Plasma concentrations of erythropoietin, angiopoietin-2, and stromal-derived growth factor (SDF)-1α were significantly higher in children with Hemoglobin SS compared to Control subjects. In a multivariate analysis model, SDF-1α concentration was found to be associated with both CPC number and total white blood cell count in the Hemoglobin SS group, suggesting that SDF-1α produced by ischemic tissues plays a role in mobilizing these cells in children with Hemoglobin SS. Despite having a higher number of angiogenic progenitor cells, children with Hemoglobin SS had slower migration of cultured mononuclear cells

Effect of IPTp on Plasmodium falciparum antibody levels among pregnant women and their babies in a sub-urban coastal area in Ghana

Abstract Background Women exposed to Plasmodium infection develop antibodies and become semi-immune. This immunity is suppressed during pregnancy making both the pregnant woman and the foetus vulnerable to the adverse effects of malaria, particularly by Plasmodium falciparum. Intermittent preventive treatment of malaria in pregnancy (IPTp) with Sulfadoxine–pyrimethamine (SP) tablets is one of the current interventions to mitigate the effects of malaria on both the pregnant woman and the unborn child. The extent to which IPTp may interfere with the acquisition of protective immunity against pregnancy-associated malaria (PAM) is undefined in Ghana. Methods Three-hundred-and-twenty pregnant women were randomly enrolled at the antenatal clinic (ANC) in Madina, Accra. Venous blood samples were obtained at first ANC registration and at 4-week intervals (post-IPTp administration). Placental and cord blood samples were obtained at delivery and the infants were followed monthly for 6 months after birth. Anti-IgG and IgM antibodies against a crude antigen preparation and the glutamate-rich protein (GLURP) of P. falciparum were quantified by the enzyme-linked immunosorbent assay (ELISA). Results There was a general decline in the trend of mean concentrations of all the antibodies from enrolment to delivery. The levels of antibodies in cord blood and placenta were well correlated. Children did not show clinical signs of malaria at 6 months after birth. Conclusions IgG against both crude antigen and GLURP were present in placenta and cord blood and it is therefore concluded that there is a trend of declining antibody from enrolment to delivery and IPTp-SP may have reduced malaria exposure, however, this does not impact on the transfer of antibodies to the foetus in utero. The levels of maternal and cord blood antibodies at delivery showed no adverse implications on malaria among the children at 6 months. However, the quantum and quality of the antibody transferred needs further investigation to ensure that the infants are protected from severe episodes of malaria.https://deepblue.lib.umich.edu/bitstream/2027.42/136792/1/12936_2017_Article_1857.pd

Plasmodium falciparum isolates from southern Ghana exhibit polymorphisms in the SERCA-type PfATPase6 though sensitive to artesunate in vitro

<p>Abstract</p> <p>Background</p> <p>In 2005, Ghana replaced chloroquine with artemisinin-based combination therapy as the first-line treatment for uncomplicated malaria. The aim of this work was to determine for the first time, polymorphisms in the putative <it>pfATPase6 </it>and <it>pftctp</it>, <it>pfmdr1</it>, <it>pfcrt </it>genes in Ghanaian isolates, particularly at a time when there is no report on artemisinin resistance in malaria parasites from Ghana. The sensitivity of parasite isolates to anti-malaria drugs were also evaluated for a possible association with polymorphisms in these genes.</p> <p>Methods</p> <p>The prevalence of point mutations in the above <it>Plasmodium falciparum </it>genes were assessed from filter-paper blood blot samples by DNA sequencing. <it>In vitro </it>drug sensitivity test was carried out on some of the blood samples from volunteers visiting hospitals/clinics in southern Ghana using a modified version of the standard WHO Mark III micro-test.</p> <p>Results</p> <p>All successfully tested parasite isolates were sensitive to artesunate; while 19.4%, 29.0% and 51.6% were resistant to quinine, amodiaquine and chloroquine respectively. The geometric mean of IC₅₀value for artesunate was 0.73 nM (95% CI, 0.38-1.08), amodiaquine 30.69 nM (95% CI, 14.18-47.20) and chloroquine 58.73 nM (95% CI, 38.08-79.38). Twenty point mutations were observed in <it>pfATPase6 </it>gene, with no L263E and S769N. All mutations found were low in frequency, except D639G which was observed in about half of the isolates but was not associated with artesunate response (<it>p </it>= 0.42). The <it>pftctp </it>gene is highly conserved as no mutation was observed, while CVIET which is chloroquine-resistant genotype at codon 72-76 of the <it>pfcrt </it>gene was identified in about half of the isolates; this was consistent with chloroquine IC₅₀values (<it>p </it>= 0.001). Mutations were present in <it>pfmdr1 </it>gene but were not associated with artemisinin response (<it>p </it>= 1.00).</p> <p>Conclusion</p> <p>The <it>pfATPase6 </it>gene is highly polymorphic with D639G appearing to be fixed in Ghanaian isolates. These may just be spontaneous mutations as all parasite isolates that were tested displayed satisfactory <it>in vitro </it>response to artesunate. However, there is no improvement in susceptibility of the parasites to chloroquine five years after its proscription.</p

Complement activation in Ghanaian children with severe Plasmodium falciparum malaria

<p>Abstract</p> <p>Background</p> <p>Severe anaemia (SA), intravascular haemolysis (IVH) and respiratory distress (RD) are severe forms of <it>Plasmodium falciparum </it>malaria, with RD reported to be of prognostic importance in African children with malarial anaemia. Complement factors have been implicated in the mechanism leading to excess anaemia in acute <it>P. falciparum </it>infection.</p> <p>Methods</p> <p>The direct Coombs test (DCT) and flow cytometry were used to investigate the mean levels of RBC-bound complement fragments (C3d and C3bαβ) and the regulatory proteins [complement receptor 1 (CD35) and decay accelerating factor (CD55)] in children with discrete clinical forms of <it>P. falciparum </it>malaria. The relationship between the findings and clinical parameters including coma, haemoglobin (Hb) levels and RD were investigated.</p> <p>Results</p> <p>Of the 484 samples tested, 131(27%) were positive in DCT, out of which 115/131 (87.8%) were positive for C3d alone while 16/131 (12.2%) were positive for either IgG alone or both. 67.4% of the study population were below 5 years of age and DCT positivity was more common in this age group relative to children who were 5 years or older (Odds ratio, OR = 3.8; 95%CI, 2.2–6.7, p < 0.001). DCT correlated significantly with RD (β = -304, p = 0.006), but multiple regression analysis revealed that, Hb (β = -0.341, p = 0.012) and coma (β = -0.256, p = 0.034) were stronger predictors of RD than DCT (β = 0.228, p = 0.061). DCT was also not associated with IVH, p = 0.19, while spleen size was inversely correlated with Hb (r = -402, p = 0.001). Flow cytometry showed similar mean fluorescent intensity (MFI) values of CD35, CD55 and C3bαβ levels on the surfaces of RBC in patients and asymptomatic controls (AC). However, binding of C3bαβ correlated significantly with CD35 or CD55 (p < 0.001).</p> <p>Conclusion</p> <p>These results suggest that complement activation contributed to anaemia in acute childhood <it>P. falciparum </it>malaria, possibly through induction of erythrophagocytosis and haemolysis. In contrast to other studies, this study did not find association between levels of the complement regulatory proteins, CD35 and CD55 and malarial anaemia. These findings suggest that complement activation could also be involved in the pathogenesis of RD but larger studies are needed to confirm this finding.</p