149 research outputs found
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
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Determinants of enrollment in the NHIS for women in Ghana
Background
The National Health Insurance Scheme (NHIS) was introduced in 2005 to provide equitable access to healthcare. Furthermore, concessions were made for pregnant women, yet inequities in access continue to exist. This study explores whether dimensions of social exclusion explain why some groups of women are not benefitting from the scheme.
Methods
Data was collected from 4050 representative households in five districts. Logistic regression is used to examine the factors that determine enrolment of women under the NHIS.
Results
The study sample consists of a sub-sample of 3,173 women out of whom 58% were insured. The majority (64.9%) of the women were in the reproductive age (15-45 years). The results show that wealth status, age, health status, locality, perception about the quality of care at health facilities and perception of the NHIS, are the key factors that determine enrolment into the scheme.
Conclusion
With women dominating the informal sector of Ghana’s economy which is often characterised by relatively low incomes, these inequities in access need to be addressed
Prevalence, incidence and severity of a new root rot disease of cowpea caused by Macrophomina phaseolina (Tassi) Goid in Northern Ghana
Cowpea is an important economic crop in northern Ghana. Following reports of a new cowpea root rot, disease in northern Ghana (Northern, Upper East and Upper West regions), surveys were conducted in 2016 and 2017 with the aim of determining the causal organism, prevalence, incidence and severity of the disease across northern Ghana under rain fed and irrigated conditions. Seventeen locations were surveyed and symptomatic plants were taken to the Plant Pathology laboratory in CSIR- Savanna Agricultural Research Institute (SARI), Nyankpala for pathogen identification. The disease was prevalent in all the locations surveyed. There was no significant difference (P > 0.05) between disease incidence and severity (1‒9 scale) under rain fed and irrigated conditions for each year. Disease incidence and severity were however significantly different (P < 0.05) amongst locations surveyed under both rain fed and irrigated production for 2016 and 2017. Under rain fed conditions for 2016, Nyankpala recorded the highest incidence (43.8%), with Feo recording the lowest (17.8%). For the same period, Manga recorded the highest severity (4.3) with Silbelle recording the least (2.1). Under dry season cultivation for 2016, Asumsapeliga recorded the highest disease incidence (44.5%) with Silbelle recording the lowest (11.4%). Sakpari, however, recorded the highest disease severity (3.8) with Feo recording the lowest for the same period. Under rain fed conditions for 2017, disease incidence was highest in Nyankpala (47.7%) and lowest in Lawra (8.7%). For the same period, however, Manga and Yendi recorded the highest severity (4.3) with Lawra recording the lowest (1.6). Under dry season cowpea production for 2017, Sakpari (64.8%) recorded the highest incidence and Silbelle (7.0%) recording the least. Disease severity for the same period was highest in Nafkluga (4.2) and lowest in Silbelle (2.3). Morphocultural characteristics and pathogenicity test confirmed Macrophomina phaseolina as the causal organism of the cowpea root rot disease
Surgically correctable adrenal-dependent hypertension: a report of five cases
Although endocrine causes of secondary hypertension are relatively uncommon, medical practitioners must maintain a high index of suspicion for them in certain categories of patients. Such patientsinclude young individuals, those with difficult- to-treat hypertension and those presenting with symptoms, clinical signs and/or laboratoryparameters well-known to be associated with Cushing’s syndrome, Conn’s syndrome or phaeochromocytoma. This paper reports on 5 patients identified over a 2-year period with various hormonally-activeadrenal adenomas causing hypertension in an environment where, hitherto, the occurrence of these conditions was generally thought to be rare. Aspects of the patients’ histories, examination and laboratory findings that drew attention to the possibility of the diagnosis in each case are highlighted, as are the confirmatory investigationsand management methods used by a multidisciplinary team of medical practitioners. The clinical outcome with appropriate treatment of adrenalrelated hypertension is good and can result in significantcost savings in the long term
The Quantity and Quality of African Children's IgG Responses to Merozoite Surface Antigens Reflect Protection against Plasmodium falciparum Malaria
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81196.pdf (publisher's version ) (Open Access)BACKGROUND: Antibodies, particularly cytophilic IgG subclasses, with specificity for asexual blood stage antigens of Plasmodium falciparum, are thought to play an important role in acquired immunity to malaria. Evaluating such responses in longitudinal sero-epidemiological field studies, allied to increasing knowledge of the immunological mechanisms associated with anti-malarial protection, will help in the development of malaria vaccines. METHODS AND FINDINGS: We conducted a 1-year follow-up study of 305 Senegalese children and identified those resistant or susceptible to malaria. In retrospective analyses we then compared post-follow-up IgG responses to six asexual-stage candidate malaria vaccine antigens in groups of individuals with clearly defined clinical and parasitological histories of infection with P. falciparum. In age-adjusted analyses, children resistant to malaria as well as to high-density parasitemia, had significantly higher IgG1 responses to GLURP and IgG3 responses to MSP2 than their susceptible counterparts. Among those resistant to malaria, high anti-MSP1 IgG1 levels were associated with protection against high-density parasitemia. To assess functional attributes, we used an in vitro parasite growth inhibition assay with purified IgG. Samples from individuals with high levels of IgG directed to MSP1, MSP2 and AMA1 gave the strongest parasite growth inhibition, but a marked age-related decline was observed in these effects. CONCLUSION: Our data are consistent with the idea that protection against P. falciparum malaria in children depends on acquisition of a constellation of appropriate, functionally active IgG subclass responses directed to multiple asexual stage antigens. Our results suggest at least two distinct mechanisms via which antibodies may exert protective effects. Although declining with age, the growth inhibitory effects of purified IgG measurable in vitro reflected levels of anti-AMA1, -MSP1 and -MSP2, but not of anti-GLURP IgG. The latter could act on parasite growth via indirect parasiticidal pathways
Evaluation of alternative school feeding models on nutrition, education, agriculture and other social outcomes in Ghana: rationale, randomised design and baseline data
Exploring the educational needs of nurses on children's pain management: A descriptive qualitative study
Aim To explore the educational needs of nurses on children's passin management. Design A descriptive qualitative study. Methods Individual and group interviews were conducted among 28 nurses and four nurse managers at four hospitals in the Ashanti region of Ghana. The recorded interviews were later transcribed verbatim and thematically analysed based on a conceptual interest in the educational needs on paediatric pain management.Results Nurses were acquainted with pain assessment of children who can verbally communicate. They mainly used drugs in treating pain and were familiar with the use of some non-pharmacological interventions. Notwithstanding, they desired to know more about pain assessment for children with non-functional speech. Additionally, they were interested in learning more about both drug and nondrug pain relief methods for children. The sampled nurses and nurse managers indicated diverse preferences on the nature of the paediatric pain educational programme based on their personal choices and working dynamics.</p
The COVID-19 pandemic in the African continent.
In December 2019, a new coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and associated disease, coronavirus disease 2019 (COVID-19), was identified in China. This virus spread quickly and in March, 2020, it was declared a pandemic. Scientists predicted the worst scenario to occur in Africa since it was the least developed of the continents in terms of human development index, lagged behind others in achievement of the United Nations sustainable development goals (SDGs), has inadequate resources for provision of social services, and has many fragile states. In addition, there were relatively few research reporting findings on COVID-19 in Africa. On the contrary, the more developed countries reported higher disease incidences and mortality rates. However, for Africa, the earlier predictions and modelling into COVID-19 incidence and mortality did not fit into the reality. Therefore, the main objective of this forum is to bring together infectious diseases and public health experts to give an overview of COVID-19 in Africa and share their thoughts and opinions on why Africa behaved the way it did. Furthermore, the experts highlight what needs to be done to support Africa to consolidate the status quo and overcome the negative effects of COVID-19 so as to accelerate attainment of the SDGs
Solid-state reference electrodes based on carbon nanotubes and polyacrylate membranes
A novel potentiometric solid-state reference electrode containing single-walled carbon nanotubes as the transducer layer between a polyacrylate membrane and the conductor is reported here. Single-walled carbon nanotubes act as an efficient transducer of the constant potentiometric signal originating from the reference membrane containing the Ag/AgCl/Cl− ions system, and they are needed to obtain a stable reference potentiometric signal. Furthermore, we have taken advantage of the light insensitivity of single-walled carbon nanotubes to improve the analytical performance characteristics of previously reported solid-state reference electrodes. Four different polyacrylate polymers have been selected in order to identify the most efficient reservoir for the Ag/AgCl system. Finally, two different arrangements have been assessed: (1) a solid-state reference electrode using photo-polymerised n-butyl acrylate polymer and (2) a thermo-polymerised methyl methacrylate:n-butyl acrylate (1:10) polymer. The sensitivity to various salts, pH and light, as well as time of response and stability, has been tested: the best results were obtained using single-walled carbon nanotubes and photo-polymerised n-butyl acrylate polymer. Water transport plays an important role in the potentiometric performance of acrylate membranes, so a new screening test method has been developed to qualitatively assess the difference in water percolation between the polyacrylic membranes studied. The results presented here open the way for the true miniaturisation of potentiometric systems using the excellent properties of single-walled carbon nanotubes
Generation of Humoral Immune Responses to Multi-Allele PfAMA1 Vaccines; Effect of Adjuvant and Number of Component Alleles on the Breadth of Response
There is increasing interest in multi-allele vaccines to overcome strain-specificity against polymorphic vaccine targets such as Apical Membrane Antigen 1 (AMA1). These have been shown to induce broad inhibitory antibodies in vitro and formed the basis for the design of three Diversity-Covering (DiCo) proteins with similar immunological effects. The antibodies produced are to epitopes that are shared between vaccine alleles and theoretically, increasing the number of component AMA1 alleles is expected to broaden the antibody response. A plateau effect could however impose a limit on the number of alleles needed to achieve the broadest specificity. Moreover, production cost and the vaccine formulation process would limit the number of component alleles. In this paper, we compare rabbit antibody responses elicited with multi-allele vaccines incorporating seven (three DiCos and four natural AMA1 alleles) and three (DiCo mix) antigens for gains in broadened specificity. We also investigate the effect of three adjuvant platforms on antigen specificity and antibody functionality. Our data confirms a broadened response after immunisation with DiCo mix in all three adjuvants. Higher antibody titres were elicited with either CoVaccine HT™ or Montanide ISA 51, resulting in similar in vitro inhibition (65–82%) of five out of six culture-adapted P. falciparum strains. The antigen binding specificities of elicited antibodies were also similar and independent of the adjuvant used or the number of vaccine component alleles. Thus neither the four extra antigens nor adjuvant had any observable benefits with respect to specificity broadening, although adjuvant choice influenced the absolute antibody levels and thus the extent of parasite inhibition. Our data confirms the feasibility and potential of multi-allele PfAMA1 formulations, and highlights the need for adjuvants with improved antibody potentiation properties for AMA1-based vaccines
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