125 research outputs found
Re-visiting the renewable energy â economic growth nexus : empirical evidence from African OPEC countries
Purpose â This paper aims to investigate the dynamic relationship between renewable energy and economic growth in African OPEC member countries (Angola, Algeria and Nigeria). Design/methodology/approach â The fully modified ordinary least squares technique for heterogeneous cointegrated panels (Pedroni, 2000) is used to estimate the parameters of the model. Findings â The study revealed four main findings. First, there is a bidirectional causality between renewable energy and economic growth in the long and the short run. Second, a bidirectional causality exists between non-renewable energy and economic growth in the short and long run. Third, a bidirectional causality exists between CO2 emissions and economic growth. Fourth, a unidirectional causality was also found between CO2 emissions and non-renewable energy consumption with the direction of causality stemming from the consumption of non-renewable energy to CO2 emissions. Practical implications â Because renewable consumption enhances growth, OPEC-member Africa countries should encourage investment in modern renewable sources that has high conversion efficiency such as solar, wind and hydro to strengthen their response to mitigating the impacts of climate change. Originality/value â This study applies multiple methods to analyze the relationship between renewable energy and economic growth in African OPEC countries
The importance of autosomal genes in Kallmann syndrome: genotype-phenotype correlations and neuroendocrine characteristics
7 pages, 2 figures, 2 tables.-- et al.Kallmann syndrome (KS) consists of congenital, isolated, idiopathic hypogonadotropic hypogonadism (IHH) and anosmia. The gene responsible for the X-linked form of KS, KAL, encodes a protein, anosmin, that plays a key role in the migration of GnRH neurons and olfactory nerves to the hypothalamus. In addition to X-linked pedigrees, autosomal dominant and recessive kindreds with KS have been reported. The relative importance of these autosomal vs. X-linked genes in producing KS, and the frequency of KAL mutations, are currently unknown because these are rare disorders and large series are unusual. We examined 101 individuals with IHH (+/- anosmia) and their families to determine their modes of inheritance, incidence of mutations in the coding sequence of KAL, genotype-phenotype correlations, and [in a subset (n = 38)] their neuroendocrine phenotype. Of the 101 patients, 59 had true KS (IHH + anosmia/hyposmia); whereas, in the remaining 42, no anosmia was evident in the patients or their families. Of the 59 KS patients, 21 were familial, whereas 38 were sporadic cases. Mutations in the coding sequence of KAL were identified in only 3 of 21 familial cases (14%) and 4 of 38 (11%) of the sporadic cases. Of the X-linked cases confirmed by mutational analysis, only 1 of 3 pedigrees appeared X-linked by inspection whereas the other 2 contained only affected brothers. Female members of known KAL mutation families (n = 3) exhibited no reproductive phenotype and were not anosmic, whereas families with anosmic women (n = 3) were not found to carry mutations in KAL. Mutations were uniformly absent in nonanosmic IHH probands (n = 42), as well as in families with both anosmic and nonanosmic members (n = 2). Overall, 4 novel mutations were identified (C172R, R191x, R457x, and delC@L600). With respect to neuroendocrine phenotype, KS men with documented KAL mutations (n = 8) had completely apulsatile LH secretion, whereas those with autosomal modes of inheritance demonstrated a more variable spectrum with evidence of enfeebled (but present) GnRH-induced LH pulses. Our conclusions are: 1) Confirmed mutations in the coding sequence of the KAL gene occur in the minority of KS cases, i.e. only 14% of familial and 11% of sporadic cases; 2) The majority of familial (and presumably sporadic) cases of KS are caused by defects in at least two autosomal genes that are currently unknown; 3) Obligate female carriers in families with KAL mutations have no discernible phenotype; 4) KAL mutations are uniformly absent in patients with either normosmic IHH or in families with both anosmic and nonanosmic individuals; and 5) Patients with KAL mutations have apulsatile LH secretion consistent with a complete absence of GnRH migration of GnRH cells into the hypothalamus, whereas evidence of present (but enfeebled) GnRH-induced LH pulses may be present in autosomal KS cases. Taken together, these findings suggest that autosomal genes account for the majority of familial cases of KS, and that unique neuroendocrine phenotypes consistent with some GnRH neuronal migration may exist in these patients.Supported by funding from CAPES, Brasilia, Brazil (to L.M.B.O.).Peer reviewe
Knowledge and perception on antimicrobial resistance and antibiotics prescribing attitude among physicians and nurses in Lambaréné region, Gabon: a call for setting-up an antimicrobial stewardship program
Background
Africa is challenged by the emergence of antimicrobial resistance (AMR). In order to improve patient management and to optimise approaches to curb the spread of antimicrobial resistance, we examined knowledge and perceptions of AMR and antibiotics prescription practices of HCW (healthcare workers) in Lambaréné, Gabon.
Methods
We conducted a self-administered, questionnaire-based survey in HCW at the regional referral hospital, a medical research centre, and peripheral health care facilities. The proportions of correct responses to questions were determined and compared between physicians and nurses using Fisherâs Exact test.
Results
A total of 47 HCW took part in the survey. Of those, 64% (30/47) recognised antibiotic resistance as a major public health issue in Gabon, but only 14/47 (30%) recognised it as a problem in their health facility. Of note, 37/47 (79%) recognised excessive use of antibiotics without microbiological confirmation in case of infection, and buying antibiotics without a prescription, as possible cause of antimicrobial resistance. Some HCW (28%; 13/47) reported having prescribed antibiotics because the patients asked for them; and a total of 15/47 (32%) responded that antibiotics could help patients recover faster when added to malaria treatment. Compared to nurses, most of the physicians recognised that excessive use of antibiotics without microbiological confirmation of infection could contribute to AMR spread (18/19 (95%) vs 19/28 (68%); pâ=â0.028).
Conclusion
Most HCW recognised AMR as public health issue. However, a quarter of the participants did not know about the causes fostering the emergence of antimicrobial resistance. There is a need to perform regular HCW training in antimicrobial prescription, and to set up an antimicrobial stewardship program
Seroprevalence of hepatitis B and C virus in HIV-1 and HIV-2 infected Gambians
BACKGROUND: The prevalence of HIV/hepatitis co-infection in sub-Saharan Africa is not well documented, while both HIV and HBV are endemic in this area. OBJECTIVE: The aim of this study is to determine the seroprevalence of HBV and HCV virus in HIV-infected subjects in the Gambia. METHODS: Plasma samples from HIV infected patients (190 individuals with clinically defined AIDS and 382 individuals without AIDS) were tested retrospectively for the presence of HBV sero-markers and for serum HBV DNA, screened for HCV infection by testing for anti-HCV antibody and HCV RNA. RESULTS: HBsAg prevalence in HIV-positive individuals is 12.2%. HIV/HBV co-infected individuals with CD4 count of <200 cells ”Lâ»Âč have a higher HBV DNA viral load than patients with higher CD4 count (log 4.0 vs. log 2.0 DNA copies/ml, p < 0.05). Males (OR = 1.8, 95% CI: 1.0, 3.2) were more likely to be HBsAg positive than female. HCV seroprevalence was 0.9% in HIV-positive individuals. CONCLUSION: The prevalence of HBsAg carriage in HIV- infected Gambians is similar to that obtained in the general population. However co-infected individuals with reduced CD4 levels, indicative of AIDS had higher prevalence of HBeAg retention and elevated HBV DNA levels compared to non-AIDS patients with higher CD4 count
Retrospective analysis of antimicrobial resistance and bacterial spectrum of infection in Gabon, Central Africa
Background: Physicians depend on reliable information on the local epidemiology of infection and antibiotic resistance rates to guide empiric treatment in critically ill patients. As these data are scarce for Central Africa, we performed a retrospective analysis of microbiological findings from a secondary care hospital in Gabon. Methods: Microbiological reports from 2009 to 2012 were used to assess the non-susceptibility rates of the three most common isolates from six major types of infections (bloodstream, ear-eye-nose-throat, surgical site, skin and soft tissue, urinary tract and wound infection). Results: A high diversity of pathogens was found, but Staphylococcus aureus was predominant in the majority of infections. Overall, the three most prevalent pathogens in children were S. aureus (33.7%), Streptococcus pyogenes (8.1%) and Escherichia coli (4.5%) and in adults S. aureus (23.5%), E. coli (15.1%) and Klebsiella pneumoniae (7.4%). In total, 5.8% (nâ=â19) of all S. aureus isolates were methicillin resistant. The proportion of extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae was 15.4% (nâ=â78), 49.4% of all K. pneumoniae were ESBL-producer (nâ=â42). Conclusion: The high diversity of potential pathogens and high resistance rates in Gram-negative bacteria challenge a rational empiric use of antibiotics. Countrywide continuous sentinel surveillance is therefore urgently needed.<br
Tuberculosis infection control measures in healthcare facilities in Moyen-Ogooué Province, Gabon
Background
Healthcare workers (HCW) are at higher risk of tuberculosis (TB) than the general population. We assessed healthcare facilities for their TB infection control standards and priorities.
Methods
A standardised tool was applied. The assessment was conducted by direct observation, documents review and interviews with the facility heads.
Results
Twenty healthcare facilities were assessed; 17 dispensaries, an HIV-clinic, a private not-for-profit hospital and a public regional hospital. In both hospitals, outpatient departments, internal medicine wards, paediatric wards, emergency departments; and the MDR-TB unit of the public regional hospital were assessed. In Gabon, there are currently no national guidelines for TB infection control (TBIC) in healthcare settings. Consequently, none of the facilities had an infection control plan or TBIC focal point. In three departments of two facilities (2/20 facilities), TB patients and presumed TB cases were observed to be consistently provided with surgical masks. One structure reported to regularly test some of its personnel for TB. Consultation rooms were adequately ventilated in six primary care level facilities (6/17 dispensaries) and in none of the hospitals, due to the use of air conditioning. Adequate personal protective equipment was not provided regularly by the facilities and was only found to be supplied in the MDR-TB unit and one of the paediatric wards.
Conclusions
In Moyen-Ogooué province, implementation of TBIC in healthcare settings is generally low. Consequently, HCW are not sufficiently protected and therefore at risk for M. tuberculosis infection. There is an urgent need for national TBIC guidelines and training of health workers to safeguard implementation
Dataset for the morphological and erythrocytes parameters of Clarias gariepinus, Pangasianodon hypophthalmus, and their reciprocal hybrid
Discrimination of different fishes can be done through different means which includes morphological appearance. When two fishes are successfully hybridized, they produce progenies that have shared morphology between their pure parent, hence, making morphometric characterization an important aspect of hybrid discrimination. However, erythrocyte characterization is also a simpler method for characterization. The dataset presented in this article represents the traditional morphological data, truss network data and erythrocyte data of pure and novel hybrids from reciprocal crosses of African catfish Clarias gariepinus and Asian catfish Pangasianodon hypophthalmus. Breeding of the broodstocks was done to produce pure and hybrid progenies which were maintained for a period of four to six months. Based on the cross combinations and morphotypes, traditional measurement of twenty-five morphological characters and five meristic counts were recorded. Thereafter pictures of the different fish groups were used to determine values of thirty-six distances between ten landmark points. The morphological abnormality of the hybrids at market size is also presented in this data article for the very first time. Blood was then collected from the caudal peduncle of ten fish per group and smeared on a slide for observation under a compound microscope (at 100 Ă magnification). Data gotten included erythrocytes parameters such as cell major axis, cell minor axis, nucleus major axis, nucleus minor axis cell area, nucleus area, cell volume, and nucleus volume. Data recording was through the Microsoft excel spreadsheet; which was also used to process the data to get the exclusive ranges of values for paired progenies. The data as presented is associated with the research article âMorphological characterization of the progenies of pure and reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878) and Clarias gariepinus (Burchell,1822)â [1].The dataset presented in this article can be used for easy identification of the novel hybrid progenies of the African Catfish and Asian Catfis
Microbiota composition data for wild and captive bluestreak cleaner wrasse Labroides dimidiatus (Valenciennes, 1839
The Labroides dimidiatus is known as the âdoctor fishâ
because of its role in removing parasites and infectious
pathogens from the body of other fishes. This important role
played both in wild and captive conditions could represent
a novel form of parasitic transmission process mediated by
the cleaning activity of the fish. Yet, there is a paucity of data on the microflora associated with this fish which is important for tracking disease infection and generally monitoring the health status of the fish. This article, therefore, represents the first dataset for the microbiota composition of wild and captive L. dimidiatus. Wild fish samples and carriage water were gotten in Terengganu Malaysia around the corals of the Karah Island. The captive sample, however, was obtained from well-known ornamental fish suppliers in Terengganu Malaysia. Thereafter, bacteria present on the skin, in the stomach and the aquarium water were enumerated using culture-independent approaches and Next Generation Sequencing (NGS) technology. Data obtained from the three metagenomic libraries using NGS analysis gave
1,426,740 amplicon sequence reads which are composed of
508 operational taxonomic units (OTUs) for wild samples and
3,238,564 valid reads and 828 OTUs for captive samples. All
sequence reads were deposited in the GeneBank (Accession
numbers SAMN14260247, SAMN14260248, SAMN14260249,
SAMN14260250, SAMN14260251, and SAMN14260252). The
dataset presented is associated with the research article â16S rDNA-Based Metagenomic Analysis of Microbial Communities Associated with Wild Labroides dimidiatus From Karah Island, Terengganu, Malaysiaâ. The microbiota data presented in this article can be used to monitor the health and wellbeing of the ornamental fish, especially under captivity, hence preventing possible cross-infectio
Phylogenomics of Mycobacterium africanum reveals a new lineage and a complex evolutionary history.
Human tuberculosis (TB) is caused by members of the Mycobacterium tuberculosis complex (MTBC). The MTBC comprises several human-adapted lineages known as M. tuberculosis sensu stricto, as well as two lineages (L5 and L6) traditionally referred to as Mycobacterium africanum. Strains of L5 and L6 are largely limited to West Africa for reasons unknown, and little is known of their genomic diversity, phylogeography and evolution. Here, we analysed the genomes of 350âL5 and 320âL6 strains, isolated from patients from 21 African countries, plus 5 related genomes that had not been classified into any of the known MTBC lineages. Our population genomic and phylogeographical analyses showed that the unclassified genomes belonged to a new group that we propose to name MTBC lineage 9 (L9). While the most likely ancestral distribution of L9 was predicted to be East Africa, the most likely ancestral distribution for both L5 and L6 was the Eastern part of West Africa. Moreover, we found important differences between L5 and L6 strains with respect to their phylogeographical substructure and genetic diversity. Finally, we could not confirm the previous association of drug-resistance markers with lineage and sublineages. Instead, our results indicate that the association of drug resistance with lineage is most likely driven by sample bias or geography. In conclusion, our study sheds new light onto the genomic diversity and evolutionary history of M. africanum, and highlights the need to consider the particularities of each MTBC lineage for understanding the ecology and epidemiology of TB in Africa and globally
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