The Hydrochemistry of Groundwater in Some Communities in the Ayensu River Basin in the Central Region of Ghana

Hydrochemical analysis of groundwater samples in some communities in the Ayensu river basin of the central Region of Ghana was used to establish the hydrochemistry of the study area. The methodology consisted of physicochemical sampling and laboratory analysis of groundwater resources in the Basin and basic statistical analysis of the laboratory results. Generally, the groundwater is weakly acidic with a mean pH value of 6.32, had high electrical conductivity and TDS values in the range, 256.4 µS cm-1 to 2313.3 µS cm-1 and 101.7 mg/L to 1247.0 mg/L respectively. The groundwater in the area is undersaturated with respect to carbonate phases and is fresh except for one borehole at Gyangyanadze which has TDS value of 1247.0 mg/L considered as saline water.  The dominant water types in the study area are Na- Cl, Ca- Mg - Cl and Ca - Mg - SO4. The groundwater is to a large extent potable. However, approximately 13% of the groundwater samples had chloride concentrations slightly exceeding the respective WHO maximum acceptable limits for drinking water. Approximately 43%, 16% and 10% respectively of the water samples had Al3+, Fe2+ and Cd2+ concentrations above the respective WHO maximum acceptable limit for drinking water.  Silicate mineral weathering is probably the main process through which major ions enter the groundwater. Keywords:Groundwater quality  hydrochemistry  silicate weathering  Central Region  Ghana 

Pharmacogenetics in Ghana: Reviewing the evidence

Different clinical response of different patients to the same medicine has been recognised and documented since the 1950’s. Variability in response of individuals to standard doses of drug therapy is important in clinicalpractice and can lead to therapeutic failures or adverse drug reactions. Pharmacogenetics seeks to identify individual genetic differences (polymorphisms) in drug absorption, metabolism, distribution and excretion that can affect the activity of a particular drug with theview of improving efficacy and reducing toxicity. Although knowledge of pharmacogenetics is being translated into clinical practice in the developed world, its applicability in the developing countries is low. Severalfactors account for this including the fact that there is very little pharmacogenetic information available in many indigenous African populations including Ghanaians. A number of genes including Cytochrome P450 (CYP) 2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, MDR1 and TPMT have been genotyped in the Ghanaian population since the completion of the Human genome project. There is however, an urgentneed to increase pharmacogenetic research in Ghana to increase availability of data. Introducing Pharmacogenetics into the curriculum of Medical and Pharmacy training institutions will influence translatingknowledge of pharmacogenetics into clinical practice. This will also equip health professionals with the skill to integrate genetic information into public health decision making

Adverse drug reaction reporting by doctors in a developing country: A case study from Ghana

Background: Spontaneous adverse drug reaction reporting is the most widely used and cost effective method of monitoring the safety of drugs. This method is heavily afflicted by underreporting by healthcare professionals. The study aims at assessing adverse drug reaction (ADR) reporting rate by doctors, knowledge of the reporting system and attitudes to SADR in the Greater Accra region.Methods: This was a cross sectional survey of 259 doctors randomly  selected from 23 hospitals classified as government 199 (76.8%), quasi-governmental 43(16.6%) and private 17 (6.6%) hospitals in the Greater Accra Region of Ghana. Data collection was by self-administered  questionnaire from May 5, 2012- July 6, 2012. Descriptive statistics was used to describe the background characteristics of the doctors and the outcome measures like training and reasons for ADR reporting were summarized as frequencies and percentages.Results: One-third (27.4%) of doctors surveyed had received previous training on drug safety monitoring and ADR reporting; training and  knowledge of the reporting system was found to improve reporting. Morethan half 154 (59.5%) of the doctors had seen a patient with suspected ADR in the past one year although only 31 (20%) had reported it by completing the SADR reporting form. Doctors working in government hospitals were about 5 times more likely to report than those in private hospitals [OR=4.94, 95%CI (1.55-15.69)].Conclusion: Training and knowledge of the ADR reporting system were found to be associated with the likelihood of reporting an ADR. Most of the doctors had not previously received training on ADR reporting.Keywords: Spontaneous reporting, adverse drug reaction, underreporting, doctors, Ghan

Analysis of photographic records of coal pyrolysis. Final report

Bituminous coals upon heating undergo melting and pyrolytic decomposition with significant parts of the coal forming an unstable liquid that can escape from the coal by evaporation. The transient liquid within the pyrolyzing coal causes softening or plastic behavior that can influence the chemistry and physics of the process. Bubbles of volatiles can swell the softened coal mass in turn affecting the combustion behavior of the coal particles. The swelling behavior of individual coal particles has to be taken into account both as the layout as well as for the operation of pyrolysis, coking and performance of coal-fired boilers. Increased heating rates generally increase the amount of swelling although it is also known that in some cases, even highly swelling coals can be transformed into char with no swelling if they are heated slowly enough. The swelling characteristics of individual coal particles have been investigated by a number of workers employing various heating systems ranging from drop tube and shock tube furnaces, flow rate reactors and electrical heating coils. Different methods have also been employed to determine the swelling factors. The following sections summarize some of the published literature on the subject and outline the direction in which the method of analysis will be further extended in the study of the swelling characteristics of hvA bituminous coal particles that have been pyrolyzed with a laser beam

LINDANE AND PROPOXUR RESIDUES IN COCOA FROM CENTRAL REGION OF GHANA

ABSTRAC

Measurement of the plasma levels of antibodies against the polymorphic vaccine candidate apical membrane antigen 1 in a malaria-exposed population

<p>Abstract</p> <p>Background</p> <p>Establishing antibody correlates of protection against malaria in human field studies and clinical trials requires, amongst others, an accurate estimation of antibody levels. For polymorphic antigens such as apical membrane antigen 1 (AMA1), this may be confounded by the occurrence of a large number of allelic variants in nature.</p> <p>Methods</p> <p>To test this hypothesis, plasma antibody levels in an age-stratified cohort of naturally exposed children from a malaria-endemic area in Southern Ghana were determined by indirect ELISA. Titres against four single <it>Pf</it>AMA1 alleles were compared with those against three different allele mixtures presumed to have a wider repertoire of epitope specificities. Associations of antibody levels with the incidence of clinical malaria as well as with previous exposure to parasites were also examined.</p> <p>Results</p> <p>Antibody titres against <it>Pf</it>AMA1 alleles generally increased with age/exposure while antibody specificity for <it>Pf</it>AMA1 variants decreased, implying that younger children (≤ 5 years) elicit a more strain-specific antibody response compared to older children. Antibody titre measurements against the FVO and 3D7 AMA1 alleles gave the best titre estimates as these varied least in pair-wise comparisons with titres against all <it>Pf</it>AMA1 allele mixtures. There was no association between antibody levels against any capture antigen and either clinical malaria incidence or parasite density.</p> <p>Conclusions</p> <p>The current data shows that levels of naturally acquired antigen-specific antibodies, especially in infants and young children, are dependent on the antigenic allele used for measurement. This may be relevant to the interpretation of antibody titre data from measurements against single <it>Pf</it>AMA1 alleles, especially in studies involving infants and young children who have experienced fewer infections.</p

Inkjet-printed graphene electrodes for dye-sensitized solar cells

We present a stable inkjet printable graphene ink, formulated in isopropyl alcohol via liquid phase exfoliation of chemically pristine graphite with a polymer stabilizer. The rheology and low deposition temperature of the ink allow uniform printing. We use the graphene ink to fabricate counter electrodes (CE) for natural and ruthenium-based dye-sensitized solar cells (DSSCs). The repeatability of the printing process for the CEs is demonstrated through an array of inkjet-printed graphene electrodes, with ∼5% standard deviation in the sheet resistance. As photosensitizers, we investigate natural tropical dye extracts from Pennisetum glaucum, Hibiscus sabdariffa and Caesalpinia pulcherrima. Among the three natural dyes, we find extracts from C. pulcherrima exhibit the best performance, with ∼0.9% conversion efficiency using a printed graphene CE and a comparable ∼1.1% efficiency using a platinum (Pt) CE. When used with N719 dye, the inkjet-printed graphene CE shows a ∼3.0% conversion efficiency, compared to ∼4.4% obtained using Pt CEs. Our results show that inkjet printable graphene inks, without any chemical functionalization, offers a flexible and scalable fabrication route, with a material cost of only ∼2.7% of the equivalent solution processed Pt-based electrodes.Authors acknowledge support from CAPREX, Cambridge Africa Alborada Fund, Carnegie-University of Ghana Next Generation of Africa Academics programme and the Royal Academy of Engineering (RAEng) through a research fellowship (Graphlex)

Mycobacterium tuberculosis proteins involved in cell wall lipid biosynthesis improve BCG vaccine efficacy in a murine TB model

OBJECTIVES: Advances in tuberculosis (TB) vaccine development are urgently required to enhance global disease management. We evaluated the potential of Mycobacterium tuberculosis (M. tb)-derived protein antigens Rv0447c, Rv2957 and Rv2958c to boost BCG vaccine efficacy in the presence or absence of glucopyranosyl lipid adjuvant formulated in a stable emulsion (GLA-SE) adjuvant. METHODS: Mice received the BCG vaccine, followed by Rv0447c, Rv2957 and Rv2958c protein boosting with or without GLA-SE adjuvant 3 and 6 weeks later. Immune responses were examined at given time points. 9 weeks post vaccination, mice were aerosol-challenged with M. tb, and sacrificed at 6 and 12 weeks to assess bacterial burden. RESULTS: Vaccination of mice with BCG and M. tb proteins in the presence of GLA-SE adjuvant triggered strong IFN-γ and IL-2 production by splenocytes; more TNF-α was produced without GLA-SE addition. Antibody responses to all three antigens did not differ, with or without GLA-SE adjuvant. Protein boosting without GLA-SE adjuvant resulted in vaccinated animals having better control of pulmonary M. tb load at 6 and 12 weeks post aerosol infection, while animals receiving the protein boost with GLA-SE adjuvant exhibited more bacteria in the lungs. CONCLUSIONS: Our data provides evidence for developing Rv2958c, Rv2957 and Rv0447c in a heterologous prime-boost vaccination strategy with BCG

Antibody responses to <i>P. falciparum</i> blood stage antigens and incidence of clinical malaria in children living in endemic area in Burkina Faso

Abstract Background High parasite-specific antibody levels are generally associated with low susceptibility to Plasmodium falciparum malaria. This has been supported by several studies in which clinical malaria cases of P. falciparum malaria were reported to be associated with low antibody avidities. This study was conducted to evaluate the role of age, malaria transmission intensity and incidence of clinical malaria in the induction of protective humoral immune response against P. falciparum malaria in children living in Burkina Faso. Methods We combined levels of IgG and IgG subclasses responses to P. falciparum antigens: Merozoite Surface Protein 3 (MSP3), Merozoite Surface Protein 2a (MSP2a), Merozoite Surface Protein 2b (MSP2b), Glutamate Rich Protein R0 (GLURP R0) and Glutamate Rich Protein R2 (GLURP R2) in plasma samples from 325 children under five (05) years with age, malaria transmission season and malaria incidence. Results We notice higher prevalence of P. falciparum infection in low transmission season compared to high malaria transmission season. While, parasite density was lower in low transmission than high transmission season. IgG against all antigens investigated increased with age. High levels of IgG and IgG subclasses to all tested antigens except for GLURP R2 were associated with the intensity of malaria transmission. IgG to MSP3, MSP2b, GLURP R2 and GLURP R0 were associated with low incidence of malaria. All IgG subclasses were associated with low incidence of P. falciparum malaria, but these associations were stronger for cytophilic IgGs. Conclusions On the basis of the data presented in this study, we conclude that the induction of humoral immune response to tested malaria antigens is related to age, transmission season level and incidence of clinical malaria

Pattern of drug utilization for treatment of uncomplicated malaria in urban Ghana following national treatment policy change to artemisinin-combination therapy

<p>Abstract</p> <p>Background</p> <p>Change of first-line treatment of uncomplicated malaria to artemisinin-combination therapy (ACT) is widespread in Africa. To expand knowledge of safety profiles of ACT, pharmacovigilance activities are included in the implementation process of therapy changes. Ghana implemented first-line therapy of artesunate-amodiaquine in 2005. Drug utilization data is an important component of determining drug safety, and this paper describes how anti-malarials were prescribed within a prospective pharmacovigilance study in Ghana following anti-malarial treatment policy change.</p> <p>Methods</p> <p>Patients with diagnosis of uncomplicated malaria were recruited from pharmacies of health facilities throughout Accra in a cohort-event monitoring study. The main drug utilization outcomes were the relation of patient age, gender, type of facility attended, mode of diagnosis and concomitant treatments to the anti-malarial regimen prescribed. Logistic regression was used to predict prescription of nationally recommended first-line therapy and concomitant prescription of antibiotics.</p> <p>Results</p> <p>The cohort comprised 2,831 patients. Curative regimens containing an artemisinin derivative were given to 90.8% (n = 2,574) of patients, although 33% (n = 936) of patients received an artemisinin-based monotherapy. Predictors of first-line therapy were laboratory-confirmed diagnosis, age >5 years, and attending a government facility. Analgesics and antibiotics were the most commonly prescribed concomitant medications, with a median of two co-prescriptions per patient (range 1–9). Patients above 12 years were significantly less likely to have antibiotics co-prescribed than patients under five years; those prescribed non-artemisinin monotherapies were more likely to receive antibiotics. A dihydroartemisinin-amodiaquine combination was the most used therapy for children under five years of age (29.0%, n = 177).</p> <p>Conclusion</p> <p>This study shows that though first-line therapy recommendations may change, clinical practice may still be affected by factors other than the decision or ability to diagnose malaria. Age, diagnostic confirmation and suspected concurrent conditions lead to benefit:risk assessments for individual patients by clinicians as to which anti-malarial treatment to prescribe. This has implications for adherence to policy changes aiming to implement effective use of ACT. These results should inform education of health professionals and rational drug use policies to reduce poly-pharmacy, and also suggest a potential positive impact of increased access to testing for malaria both within health facilities and in homes.</p