Laboratory Elements For Accurate Detection Of Iron Deficiency In Resource-Limited Settings Of Africa

No Abstrac

Rift Valley Fever Virus Seroprevalence in Human Rural Populations of Gabon

Rift Valley fever (RVF) is a disease transmitted by a mosquito bite (Aedes). Humans can also be infected through direct contact with blood (aerosols) or tissues (placenta, stillborn) of infected animals. Although severe clinical cases can be observed, infection with RVF virus (RVFV) in humans in most cases causes a febrile illness without serious symptoms. In small ruminants RVFV mainly causes abortion and neonatal death. RVFV distribution has been poorly investigated in Central Africa. We conducted a large scale serological survey of RVF antibodies in rural populations in Gabon, involving 4,323 individuals from 212 randomly selected villages. The results showed an overall RVFV prevalence of 3.3%, with values of 2.9% in the forested zones, 2.2% in savannas and 8.3% in the lakes region. These findings strongly suggest for the first time the wide circulation of Rift valley fever virus in Gabon and the possible existence of a sylvan cycle of RVF virus in this country. The serological higher prevalence in the lake region suggests that this region is likely to have particular ecological conditions, especially mosquito vector species, favoring the circulation of this virus. In Gabon, human cases of RVF may occur but are either misdiagnosed or not reported

NMR and MS study of the formation of β-D-glucopyranosylamine uronic acid in aqueous solution

International audienc

Human papillomavirus detection using the Abbott RealTime high-risk HPV tests compared with conventional nested PCR coupled to high-throughput sequencing of amplification products in cervical smear specimens from a Gabonese female population

Background: Cervical cancer is the fourth most common malignancy in women worldwide. However, screening with human papillomavirus (HPV) molecular tests holds promise for reducing cervical cancer incidence and mortality in low-and middle-income countries. The performance of the Abbott RealTime High-Risk HPV test (AbRT) was evaluated in 83 cervical smear specimens and compared with a conventional nested PCR coupled to high-throughput sequencing (HTS) to identify the amplicons. Results: The AbRT assay detected at least one HPV genotype in 44.57% of women regardless of the grade of cervical abnormalities. Except for one case, good concordance was observed for the genotypes detected with the AbRT assay in the high-risk HPV category determined with HTS of the amplicon generated by conventional nested PCR. Conclusions: The AbRT test is an easy and reliable molecular tool and was as sensitive as conventional nested PCR in cervical smear specimens for detection HPVs associated with high-grade lesions. Moreover, sequencing amplicons using an HTS approach effectively identified the genotype of the hrHPV identified with the AbRT test

Kinetic and therapeutic properties of macrocyclic lactone endectocides, doramectin and moxidectin, in N’Dama cattle (<em>Bos taurus</em>) in Gabon

The plasma kinetics and efficacy of doramectin and moxidectin were studied in N’Dama taurine cattle after subcutaneous administration at the recommended dose of 0.2 mg/kg. Absorption half-life values showed that the absorption of moxidectin (0.05 day) was significantly faster than that of doramectin (1.7 day). No significant differences were observed in maximum concentrations, but they were reached earlier with moxidectin (0.3 day) than with doramectin (4.8 days). Exposure, measured by the area under the curve, was higher for doramectin (458 ng.day/ml) than for moxidectin (159 ng.day/ml), whereas moxidectin seemed more remanent. Both molecules showed 100% efficacy between days 15 and 30 posttreatment. These results are similar to those observed in other taurine breeds. Doramectin and moxidectin can therefore be recommended to control gastrointestinal parasitoses in N’Dama in humid tropical regions

Multi-stakeholder collaboration yields valuable data for cetacean conservation in Gamba, Gabon

Private industry, the Government of Gabon and two international NGOs collaborated to conduct marine surveys off the coast of Gabon, Central Africa. Surveys addressed multiple objectives of surveillance and monitoring, the documentation of the distribution of and threats to the marine megafauna, and capacity-building among government agents and local early-career scientists. During 22 days of survey effort over a two-year period, observers documented humpback whales Megaptera novaeangliae, bottlenose dolphins Tursiops truncatus, Atlantic humpback dolphins Sousa teuszii and common dolphins Delphinus delphis. Humpback whale presence was limited to the months of July to November. Bottlenose dolphins were present year-round and photo-identification of individuals indicated a closed, resident population, with an abundance estimate of 118 (CV = 21.6%, 95% CI 78–180). Small open-decked fishing vessels with gillnets were observed concentrated around river mouths within 2 km of shore, while commercial trawlers were at least 10 km offshore; all were confirmed to be registered and legal. Observations of marine turtles, flocks of marine birds, and floating logs and other debris were sparse. This multi-stakeholder collaboration to conduct a marine survey can serve as an effective model by which funding and logistic support from private industry paired with technical expertise from NGOs and academic institutions can benefit marine and coastal conservation.Keywords: fishing pressure, marine survey, Megaptera novaeangliae, photo-identification, relative abundance, Sousa teuszii, stakeholder engagement, Tursiops truncatu

The kaolinite shuttle links the Great Oxidation and Lomagundi events

The ~2.22–2.06 Ga Lomagundi Event was the longest positive carbon isotope excursion in Earth’s history and is commonly interpreted to reflect perturbations in continental weathering and the phosphorous cycle. Previous models have focused on mechanisms of increasing phosphorous solubilization during weathering without focusing on transport to the oceans and its dispersion in seawater. Building from new experimental results, here we report kaolinite readily absorbs phosphorous under acidic freshwater conditions, but quantitatively releases phosphorous under seawater conditions where it becomes bioavailable to phytoplankton. The strong likelihood of high weathering intensities and associated high kaolinite content in post-Great-Oxidation-Event paleosols suggests there would have been enhanced phosphorus shuttling from the continents into marine environments. A kaolinite phosphorous shuttle introduces the potential for nonlinearity in the fluxes of phosphorous to the oceans with increases in chemical weathering intensity

Geographical analysis for the integration of a microalgae production and biorefining unit in "Pays de la Loire"

International audienceMicroalgae are photosynthetic species able to transform carbon dioxide, for example from combustion processes, into biomass and valuable molecules (lipids, proteins, antioxidants, polysaccharides etc.). The team “Marine bioprocesses and separations” of GEPEA laboratory has been developing an integrated approach to valorise microalgae, from the culture to the biorefinery, for several years. A new collaboration was build with geographers (LETG-Nantes) to explore the French geographic areas where an industrial microalgae production and biorefining unit could be built. A database on the scale of metropolitan France was realized including the parameters for the culture of microalgae (light, water, carbon dioxide, nitrogen, phosphorus, heat, available lands). Three sizes of production unit were taken into account to identify potential zones of installation. Maps were then produced to compare the most interesting sites. This first work was followed by a second, to study more details on the coast of Pays de la Loire. Besides the choice of the site, new criteria were added: regulatory requirements in the installation, perception of the project by local actors (local authorities, public, neighbourhood) that must be known to prepare a local integration