Search

Dans la communauté sélaka, le métallurgiste ou nougou, use de sa connaissance cosmique, botanique et géologique pour transformer les pierres sombres en un objet utilitaire. Au plan social, il reste un acteur aux multiples fonctions. Cet article vise à montrer leur contenu et expression. A cet effet, à la suite des recherches documentaires, des enquêtes orales ont été menées auprès des métallurgistes, des notables, propriétaires terriens et d’autres membres de la société sélaka. Des données, il ressort que le nougou joue un rôle important dans la défense, la thérapie, la médiation et les échanges commerciaux. Mais avant l’exposé de ces différents résultats, un rappel historique à travers les vestiges métallurgiques sélaka s’impose.

Rainwater pollution in urban areas is a real phenomenon globally, particularly in developing countries. This study aims to trace the origin of polycyclic aromatic hydrocarbons (PAHs) in the Abidjan district's rainwater and to evaluate the health risk to the population. Ten water samples were collected at two sites during the dry and rainy seasons over a 2-year period. The use of molecular indices and profiles as well as Spearman's correlation matrix revealed that the pyrolytic sources, such as wood combustion as well as road traffic, remain the main sources of these pollutants in the water. The risk assessment revealed a higher risk of skin cancer in children. HIGHLIGHTS Sources of polycyclic aromatic hydrocarbons (PAHs) in rainwater have been identified.; The C13 isotope to the confirmation of PAH sources in rainwater has been contributed.; Children have a higher risk of skin cancer than adults.; There is a seasonal variation of PAH concentartions in rainwater.; There is an annual variation of PAH concentrations in rainwater.;

Abstract Background Surveillance programmes often use malaria rapid diagnostic tests (RDTs) to determine the proportion of the population carrying parasites in their peripheral blood to assess the malaria transmission intensity. Despite an increasing number of reports on false-negative and false-positive RDT results, there is a lack of systematic quality control activities for RDTs deployed in malaria surveillance programmes. Methods The diagnostic performance of field-deployed RDTs used for malaria surveys was assessed by retrospective molecular analysis of the blood retained on the tests. Results Of the 2865 RDTs that were collected in 2018 on Bioko Island and analysed in this study, 4.7% had a false-negative result. These false-negative RDTs were associated with low parasite density infections. In 16.6% of analysed samples, masked pfhrp2 and pfhrp3 gene deletions were identified, in which at least one Plasmodium falciparum strain carried a gene deletion. Among all positive RDTs analysed, 28.4% were tested negative by qPCR and therefore considered to be false-positive. Analysing the questionnaire data collected from the participants, this high proportion of false-positive RDTs could be explained by P. falciparum histidine rich protein 2 (PfHRP2) antigen persistence after recent malaria treatment. Conclusion Malaria surveillance depending solely on RDTs needs well-integrated quality control procedures to assess the extent and impact of reduced sensitivity and specificity of RDTs on malaria control programmes.

Within the framework of the DACCIWA (Dynamics–Aerosol–Chemistry–Cloud Interactions in West Africa) project and based on a field experiment conducted in June and July 2016, we analyze the daytime breakup of continental low-level stratiform clouds in southern West Africa. We use the observational data gathered during 22 precipitation-free occurrences at Savè, Benin. Our analysis, which starts from the stratiform cloud formation usually at night, focuses on the role played by the coupling between cloud and surface in the transition towards shallow convective clouds during daytime. It is based on several diagnostics, including the Richardson number and various cloud macrophysical properties. The distance between the cloud base height and lifting condensation level is used as a criterion of coupling. We also make an attempt to estimate the most predominant terms of the liquid water path budget in the early morning. When the nocturnal low-level stratiform cloud forms, it is decoupled from the surface except in one case. In the early morning, the cloud is found coupled with the surface in 9 cases and remains decoupled in the 13 other cases. The coupling, which occurs within the 4 h after cloud formation, is accompanied by cloud base lowering and near-neutral thermal stability in the subcloud layer. Further, at the initial stage of the transition, the stratiform cloud base is slightly cooler, wetter and more homogeneous in coupled cases. The moisture jump at the cloud top is usually found to be lower than 2 g kg−1 and the temperature jump within 1–5 K, which is significantly smaller than typical marine stratocumulus and explained by the monsoon flow environment in which the stratiform cloud develops over West Africa. No significant difference in liquid water path budget terms was found between coupled and decoupled cases. In agreement with previous numerical studies, we found that the stratiform cloud maintenance before sunrise results from the interplay between the predominant radiative cooling, entrainment and large-scale subsidence at its top. Three transition scenarios were observed depending on the state of coupling at the initial stage. In coupled cases, the low-level stratiform cloud remains coupled until its breakup. In five of the decoupled cases, the cloud couples with the surface as the lifting condensation level rises. In the eight remaining cases, the stratiform cloud remains hypothetically decoupled from the surface throughout its life cycle since the height of its base remains separated from the condensation level. In cases of coupling during the transition, the stratiform cloud base lifts with the growing convective boundary layer roughly between 06:30 and 08:00 UTC. The cloud deck breakup, occurring at 11:00 UTC or later, leads to the formation of shallow convective clouds. When the decoupling subsists, shallow cumulus clouds form below the stratiform cloud deck between 06:30 and 09:00 UTC. The breakup time in this scenario has a stronger variability and occurs before 11:00 UTC in most cases. Thus, we argue that the coupling with the surface during daytime hours has a crucial role in the low-level stratiform cloud maintenance and its transition towards shallow convective clouds.

The objective of the present study was to determine the prevalence of occupational asthma symptoms among bakery workers. A cross-sectional study was done in the District of Abidjan from February to September 2019 among bakery workers. The study covered all workers aged 18 and over, employed and present in the bakery during interviews and lung tests. The socio-demographic and professional questionnaire of the American Thoracic Society was used, and the obtained qualitative and quantitative data obtained were analyzed with Stata 15.1 software. Out of the 599 workers included in our study, we had 405 bakers (67.6%, IC 95% [0.637–0.712]), 127 salespersons/cashiers (21.2%, IC 95% [0.181–0.247]), 38 cleaning persons (6.3%, IC 95% [0.046–0.086]) and 29 administrative staff (4.8%, IC 95% [0.034–0.069]). 85.8% (IC 95% [0.828–0.884]) of workers did not have the professional qualification in the bakery sector and 11.3% (IC 95% [0.090–0.142]) were illiterate. The prevalence of probable occupational asthma was 9.7%, 2.3%, 0.6% and 1.2%, respectively, among bakers, salespersons/cashiers, cleaning persons and administrative staff. Furthermore, logistic regression analysis revealed a relationship between probable occupational asthma and family history of asthma among the bakers. As a conclusion, the exposure of bakery workers to flour appeared to be one of the risk factors for probable occupational asthma and the work-related asthma. Also, bakers with a family history of asthma had high risk of developing probable occupational asthma.

BackgroundRegular and comprehensive epidemiological surveys of the filarial nematodes Mansonella perstans and Loa loa in children, adolescents and adults living across Bioko Island, Equatorial Guinea are lacking. We aimed to demonstrate that blood retained on malaria rapid diagnostic tests, commonly deployed for malaria surveys, could be used as a source of nucleic acids for molecular based detection of M. perstans and L. loa. We wanted to determine the positivity rate and distribution of filarial nematodes across different age groups and geographical areas as well as to understand level of co-infections with malaria in an asymptomatic population.MethodologyM. perstans, L. loa and Plasmodium spp. parasites were monitored by qPCR in a cross-sectional study using DNA extracted from a subset malaria rapid diagnostic tests (mRDTs) collected during the annual malaria indicator survey conducted on Bioko Island in 2018.Principal findingsWe identified DNA specific for the two filarial nematodes investigated among 8.2% (263) of the 3214 RDTs screened. Positivity rates of M. perstans and L. loa were 6.6% and 1.5%, respectively. M. perstans infection were more prominent in male (10.5%) compared to female (3.9%) survey participants. M. perstans parasite density and positivity rate was higher among older people and the population living in rural areas. The socio-economic status of participants strongly influenced the infection rate with people belonging to the lowest socio-economic quintile more than 3 and 5 times more likely to be L. loa and M. perstans infected, respectively. No increased risk of being co-infected with Plasmodium spp. parasites was observed among the different age groups.Conclusions/significanceWe found otherwise asymptomatic individuals were infected with M. perstans and L. loa. Our study demonstrates that employing mRDTs probed with blood for malaria testing represents a promising, future tool to preserve and ship NAs at room temperature to laboratories for molecular, high-throughput diagnosis and genotyping of blood-dwelling nematode filarial infections. Using this approach, asymptomatic populations can be reached and surveyed for infectious diseases beyond malaria.

Indoor air pollution associated with cooking and heating biomass fuel burning is estimated to be responsible for 7 million deaths in 2016 and most of these deaths occur in low and middle income countries. In Côte d'Ivoire, 73% of the population is reported using biomass (charcoal or wood) for cooking. The active device 3M EVM-7 was used to measure PM2.5 daily average concentrations inside and outside households in areas close (Andokoi) and far (Lubafrique) to an industrial zone in two popular neighborhoods of Yopougon, the largest and most populated municipality of the city of Abidjan (Côte d’Ivoire). PM2.5 daily average concentrations indoors and outdoors are respectively 121±12 µg/m3 and 117±8 µg/m3 in Andokoi and 32±3 µg/m3 and 41±4 µg/m3 in Lubafrique well above the World Health Organization guideline value (25 µg/m3) for air quality. Using multivariable models, the results were the number of windows in bedrooms and kitchens located outdoor were negatively correlated with the concentration of indoor PM2.5. The outdoor concentrations of PM2.5, were higher according to the cooking fuel type.

Summary: The composition of the secretome depends on the combined action of cargo receptors that facilitate protein transport and sequential checkpoints that restrict it to native conformers. Acting after endoplasmic reticulum (ER)-resident chaperones, ERp44 retrieves its clients from downstream compartments. To guarantee efficient quality control, ERp44 should exit the ER as rapidly as its clients, or more. Here, we show that appending ERp44 to different cargo proteins increases their secretion rates. ERp44 binds the cargo receptor ER-Golgi intermediate compartment (ERGIC)-53 in the ER to negotiate preferential loading into COPII vesicles. Silencing ERGIC-53, or competing for its COPII binding with 4-phenylbutyrate, causes secretion of Prdx4, an enzyme that relies on ERp44 for intracellular localization. In more acidic, zinc-rich downstream compartments, ERGIC-53 releases its clients and ERp44, which can bind and retrieve non-native conformers via KDEL receptors. By coupling the transport of cargoes and inspector proteins, cells ensure efficiency and fidelity of secretion.

Traffic source emission inventories for the rapidly growing West African urban cities are necessary for better characterization of local vehicle emissions released into the atmosphere of these cities. This study is based on local field measurements in Yopougon (Abidjan, Côte d’Ivoire) in 2016; a site representative of anthropogenic activities in West African cities. The measurements provided data on vehicle type and age, traveling time, fuel type, and estimated amount of fuel consumption. The data revealed high traffic flow of personal cars on highways, boulevards, and backstreets, whereas high flows of intra-communal sedan taxis were observed on main and secondary roads. In addition, the highest daily fuel consumption value of 56 L·day−1 was recorded for heavy vehicles, while the lowest value of 15 L·day−1 was recorded for personal cars using gasoline. This study is important for the improvement of uncertainties related to the different databases used to estimate emissions either in national or international reports. This work provides useful information for future studies on urban air quality, climate, and health impact assessments in African cities. It may also be useful for policy makers to support implementation of emission reduction policies in West African cities.

Background: SCORing for Atopic Dermatitis (SCORAD) is a tool developed by the European Task Force on Atopic Dermatitis (AD) which is used by physicians to assess AD severity during consultations with their patients. Patient‐Oriented SCORAD (PO‐SCORAD) is a self‐assessment tool for use by patients which has been validated in a study performed in European countries. However, there is currently no adapted tool for evaluating AD severity in black skin. Objective: To evaluate the performance of the version of the PO‐SCORAD specifically adapted for black skin patients (children and adults) with AD. Methods: In this multicenter, cross‐sectional and non‐interventional study, children and adults with AD were recruited during regular consultations. This international study was performed in seven sub‐Saharan countries (Benin, Burkina Faso, Cameroon, Ivory Coast, Gabon, Mali and Senegal). During the consultation, AD severity was assessed by the physician using SCORAD score and by the patients or parents using PO‐SCORAD. Results: One hundred and thirteen patients were included, 72 children and 41 adults, mainly females (61.6%). SCORAD assessed by physicians and PO‐SCORAD assessed by patients/parents were well correlated (r = 0.66, P < 0.0001). Correlation coefficients for SCORAD and PO‐SCORAD subscale scores were also good, except for symptom intensity criteria. Conclusion: Altogether, these data indicate that PO‐SCORAD for black skin correlates well with SCORAD and is therefore a valuable tool, which requires no specific level of education, for use by black skin patients with AD. [ABSTRACT FROM AUTHOR]

We use space-based observations of NO2 columns from the Global Ozone Monitoring Experiment (GOME) to map the spatial and seasonal variations of NOx emissions over Africa during 2000. The GOME observations show not only enhanced tropospheric NO2 columns from biomass burning during the dry season but also comparable enhancements from soil emissions during the rainy season over the Sahel. These soil emissions occur in strong pulses lasting 1–3 weeks following the onset of rain, and affect 3 million km2 of semiarid sub-Saharan savanna. Surface observations of NO2 from the International Global Atmospheric Chemistry (IGAC)/Deposition of Biochemically Important Trace Species (DEBITS)/Africa (IDAF) network over West Africa provide further evidence for a strong role for microbial soil sources. By combining inverse modeling of GOME NO2 columns with space-based observations of fires, we estimate that soils contribute 3.3 ± 1.8 TgN/year, similar to the biomass burning source (3.8 ± 2.1 TgN/year), and thus account for 40% of surface NOx emissions over Africa. Extrapolating to all the tropics, we estimate a 7.3 TgN/year biogenic soil source, which is a factor of 2 larger compared to model-based inventories but agrees with observation-based inventories. These large soil NOx emissions are likely to significantly contribute to the ozone enhancement originating from tropical Africa., Engineering and Applied Sciences

Buruli ulcer is a chronic and infectious skin disease, caused by Mycobacterium ulcerans. It leads to large skin ulceration and sometimes bone infection which is responsible for deformities. Here, we report a case of multifocal form of Buruli ulcer associated with secondary infection in a 46-year-old human immunodeficiency virus (HIV) positive woman. The antimycobacterial drugs combined to surgery allowed curing this multifocal case and rose up two relevant issues: the susceptibility of immune reconstitution inflammatory syndrome (IRIS) occurrence and Mycobacterium dissemination. The deep immune depression, the underline biological, and clinical disorders of the patient might contribute to IRIS occurrence and Buruli ulcer dissemination. Future investigations have to be conducted on the mechanism of IRIS on set and on Mycobacterium ulcerans dissemination after ARV drugs initiation and the patient related underline clinical or biological disorders.

The aim of this study is to contribute to the valorization of the cocoa bean varieties “Mercedes” and “Forastero” grown in Côte d’Ivoire. A comparative characterisation of phenolic compounds and minerals in the beans of the “Mercedes” and “Forastero” varieties from two major cocoa production areas of Côte d’Ivoire were determined. The phenolic compounds of cocoa beans were determined by high performance liquid chromatography (HPLC) and the minerals by atomic absorption spectrophotometer. The study showed that a significant difference at the 5% level was observed in the averages of minerals, cinnamic acid, protocatechic acid, quercetin, coumaric acid, rutin, ellagic acid, veratric acid, epicatechin, ferulic acid and naringenin. On the other hand, no significant difference at the 5% level was observed in the averages of arbutin, catechin, vanillic acid and caffeic acid in the bean kernels analysed in the Divo and Abengourou regions. The proportion of cinnamic acid is (6.18±0.63 mg/100g “Mercedes” Divo), that of ellagic acid is (18.48±0.44 mg/100g “Mercedes” Divo) and that of naringenin is (5.95±0.35 mg/100g “Mercedes” Divo). The amount of potassium is (7569.97±1.51 mg/kg “Forastero” of Abengourou) and that of iron is (179.9 ± 0.70 mg/Kg “Forastero” of Divo). The phenolic compounds and minerals in the cocoa bean samples analysed are highly correlated and rich in antioxidants. They would be beneficial for many biological functions. They can be recommended in pharmacology and cosmetics to fight against oxidative stress and cardiovascular diseases.

We report the first case of allergy to red meat observed in Ivory Coast. A 49-year-old male presented with pruritus. The diagnosis of allergy to red meat was confirmed by an assay for IgE antibodies specific for alpha-1,3 galactose. Interestingly, the disease was considered a spell to the patient who was suspected of being a sorcerer by the community.

Thiol groups can undergo numerous modifications, making cysteine a unique molecular switch. Cysteine plays structural and regulatory roles as part of proteins or glutathione, contributing to maintain redox homeostasis and regulate signaling within and amongst cells. Not surprisingly therefore, cysteines are associated with many hereditary and acquired diseases. Mutations in the primary protein sequence (gain or loss of a cysteine) are most frequent in membrane and secretory proteins, correlating with the key roles of disulfide bonds. On the contrary, in the cytosol and nucleus, aberrant post-translational oxidative modifications of thiol groups, reflecting redox changes in the surrounding environment, are a more frequent cause of dysregulation of protein function. This essay highlights the regulatory functions performed by protein cysteine residues and provides a framework for understanding how mutation and/or (in)activation of this key amino acid can cause disease.

HIV testing is crucial for starting ART earlier in HIV-infected people. We describe Missed Opportunities (MO) for HIV testing among adults newly diagnosed with HIV in Abidjan, Côte d'Ivoire.Between april,2nd 2013 and april 1st 2014, a cross-sectional study was conducted among all adults newly diagnosed (< 1year) for HIV at the Blood Donors Medical Center of Abidjan with face to face questionnaire. An MO for HIV testing was defined as a medical consultation for a clinical indicator (e.g. symptoms, hospitalization, and pregnancy) or a non-clinical indicator (e.g. high-risk sexual behavior, HIV-infected partner) potentially related to an HIV infection but did not lead to HIV test proposal by a health care professional.Of the 341 patients who attended the center suring this period, 273 (157 women and 116 men) were included in this analysis. 130 (47.6%) reported at least one medical consultation for an indicator relevant for a test proposal between 1 month and five years prior to their diagnosis. Among them, 92 (77.3%) experienced at least one MO for testing. The 273 included patients reported a total of 216 indicators; 146 (67.6%) were reported without test proposal and thus were MO. Hospitalization, extreme lose of weight, chronic or repeat fever and herpes zoster were the indicators with the largest number of MO. While 66 (24.2%) patients experienced non-clinical indicators relevant to risk of HIV infection, only 11 (4.0%) mentioned it to a health professional.MO for HIV testing are frequent, even in situations for which testing is clearly recommended. Better train healthcare professionals and creating new opportunities of testing inside and, outside of medical settings are crucial to improve HIV control.

This work is part of the IDAF program (IGAC-DEBITS-AFRICA) and is based on the long-term monitoring of gas concentrations (1998–2007) established at seven remote sites representative of major African ecosystems. Dry deposition fluxes were estimated by the inferential method using on the one hand surface measurements of gas concentrations (NO2, HNO3, NH3, SO2 and O3) and on the other hand modeled exchange rates. Dry deposition velocities (Vd) were calculated using the big-leaf model of Zhang et al. (2003b). The bidirectional approach is used for NH3 surface–atmosphere exchange (Zhang et al., 2010). Surface and meteorological conditions specific to IDAF sites have been used in the models of deposition. The seasonal and annual mean variations of gaseous dry deposition fluxes (NO2, HNO3, NH3, O3 and SO2) are analyzed. Along the latitudinal transect of ecosystems, the annual mean dry deposition fluxes of nitrogen compounds range from −0.4 to −0.8 kg N ha−1 yr−1 for NO2, from −0.7 to −1.0 kg N ha−1 yr−1 for HNO3 and from −0.7 to −8.3 kg N ha−1 yr−1 for NH3 over the study period (1998–2007). The total nitrogen dry deposition flux (NO2+HNO3+NH3) is more important in forests (−10 kg N ha−1 yr−1) than in wet and dry savannas (−1.6 to −3.9 kg N ha−1 yr−1). The annual mean dry deposition fluxes of ozone range between −11 and −19 kg ha−1 yr−1 in dry and wet savannas, and −11 and −13 kg ha−1 yr−1 in forests. Lowest O3 dry deposition fluxes in forests are correlated to low measured O3 concentrations, lower by a factor of 2–3, compared to other ecosystems. Along the ecosystem transect, the annual mean of SO2 dry deposition fluxes presents low values and a small variability (−0.5 to −1 kg S ha−1 yr−1). No specific trend in the interannual variability of these gaseous dry deposition fluxes is observed over the study period.

Melanoma is a malignant tumor rarely being described in sub-Saharan Africa. We reported an unusual and atypical clinical presentation. It was a 59-year-old patient who was hospitalized for a monomelic black tumor evolving for 10 years. Histopathological examination confirmed the melanocytic origin of this tumor. Paraclinical assessment did not find any visceral metastasis. A partial resection of the tumor was performed. The patient left the hospital against medical consent due to lack of technical facilities. The delay in the consultation and the lack of knowledge of melanoma by doctors and patients might contribute to the severity and the difficulties of its management.

Precise coordination of protein biogenesis, traffic and homeostasis within the early secretory compartment (ESC) is key for cell physiology. As a consequence, disturbances in these processes underlie many genetic and chronic diseases. Dynamic imaging methods are needed to follow the fate of cargo proteins and their interactions with resident enzymes and folding assistants. Here we applied the Halotag labelling system to study the behavior of proteins with different fates and roles in ESC: a chaperone, an ERAD substrate and an aggregation-prone molecule. Exploiting the Halo property of binding covalently ligands labelled with different fluorochromes, we developed and performed non-radioactive pulse and chase assays to follow sequential waves of proteins in ESC, discriminating between young and old molecules at the single cell level. In this way, we could monitor secretion and degradation of ER proteins in living cells. We can also follow the biogenesis, growth, accumulation and movements of protein aggregates in the ESC. Our data show that protein deposits within ESC grow by sequential apposition of molecules up to a given size, after which novel seeds are detected. The possibility of using ligands with distinct optical and physical properties offers a novel possibility to dynamically follow the fate of proteins in the ESC.

Mitochondrial biogenesis is a complex process. It necessitates the contribution of both the nuclear and the mitochondrial genomes and therefore crosstalk between the nucleus and mitochondria. It is now well established that cellular mitochondrial content can vary according to a number of stimuli and physiological states in eukaryotes. The knowledge of the actors and signals regulating the mitochondrial biogenesis is thus of high importance. The cellular redox state has been considered for a long time as a key element in the regulation of various processes. In this paper, we report the involvement of the oxidative stress in the regulation of some actors of mitochondrial biogenesis.

Abstract: SnO2 thin layers were deposited by the way of the micro-droplet technique. The sensor substrate consisted of a thin membrane developed on oxidised silicon wafer. The sensing layers were deposited by means of the micro-droplet technique into thin layers of about 100nm. Such devices were tested for benzene detection. The obtained results showed a very high sensitivity for this chemical compound since 500ppb were detected. The results presented in this paper were not focused on the reactional mechanism of benzene detection but rather on the development of a cheap and sensitive sensor using sol–gel and micro-droplet processes. Since these layers were elaborated using solely tin oxide, the as-obtained sensors are not selective but these one are intended to be used by coupling with additional devices such as chromatographic micro-column and micro-pre-concentrators. [Copyright &y& Elsevier]