Gerbillus nigeriae is a sand-dwelling and semi-arid adapted rodent species restricted to the West African Sahel where it causes extensive damages to cereal crops such as millet and sorghum. It also displays one of the most extensive floating chromosomal polymorphisms currently known in mammals, showing a non-random spatial distribution of diploid numbers (2N). We combined population dynamics and genetics to determine dispersal and mobility parameters of G. nigeriae in the species distribution range characterized by low 2N. To do so, we performed a three-year long population survey at Gangara, in the central east Niger. We used both time-dependent monitoring trough capture-mark-recapture (CMR) methods and genetic analyses performed on the 134 monitored individuals. CMR results showed low to very low population densities (maximum 27.5 individuals/ha) throughout the study. Abundance cycle was single-phased and strongly dependent on rainfall patterns. Mobility parameters showed very low individual mobility, with means of distance between successive (re) captures (DRS) and maximal distance between (re) captures (DMR) of 7.8 and 14.4 meters, respectively. Genetic analyses revealed significant isolation by distance as well as spatial structuration, thus confirming poor dispersal capacity. Our results are discussed in terms of rodent pest control in arid areas of Niger where cereal crops production is crucial for human food security.

Hemodialysis is an extrarenal purification technique widely used to increase life expectancy during chronic kidney disease. The latter contrasts with an impairment of quality of life due to joint complications caused by amyloidosis, resulting from the increase in the blood of beta-2 microglobulin (β2m). The objectives of our study were to determine the variation of serum β2m in chronic hemodialysis patients monitored at the nephrology department hemodialysis unit of Aristide Le Dantec Hospital and to investigate possible correlations between serum β2m and epidemiological parameters on the one hand and those of hemodialysis on the other. Serum β2m was measured by a two-step sandwich immunoassay method with final fluorescence detection, using the VIDAS 3 (BIOMERIEUX) immunoassay automaton. The study population consisted of 35 patients, 57 % male and 43 % female, the mean age was 48.97 years. The average length of time on dialysis was 5.94 years. The initial nephropathy was nephroangiosclerosis in 40 % of cases. The vascular approach was by an arteriovenous fistula in 91.4 % and a temporary venous catheter in 8.6 %, only a synthetic membrane was used. Serum β2m values were high with an average of 43.88 mg / l. Elevations in β2m were correlated with sex (p = 0.007), age (p = 0.007), length of time on dialysis (p = 0.0001) and residual diuresis (p = 0.035). Therefore, it is important to include β2m in the kidney disease monitoring report.

Hepatocellular carcinoma (HCC) is a public health problem in developing countries where chronic HBV is endemic. The objective of our study was to determine the prevalence of KRAS and BRAF mutations in patients with HCC. Mutations in codons 12 and 13 of KRAS and the V600E mutation of the BRAF gene were searched by HRM on Light Cycler 480 and confirmed by direct sequencing. A total of 34 HCC patients underwent molecular testing for codon 12 and 13 mutations in the KRAS gene and the V600E mutation in the BRAF gene. Melting curve analysis showed a prevalence of 23.5% (n=8/34) for the KRAS gene and 41.2% (n=14/34) for the BRAF gene. The mean age of BRAF mutation carriers was lower compared with KRAS mutation carriers. Chronic HBV carriage appeared to play a role in the development of these mutations, increasing the risk by 2 (CI(95)=0. 55-7.24; p=0.395) for BRAF and by 1.78 (CI(95)=0.23-13.5; p=1) for KRAS. KRAS and BRAF mutations do not appear to play a role in tumor metastasis. However, these results need to be confirmed by further studies with a larger sample size. Alterations in the RAS/RAF/MAP Kinase pathway appear to be more prominent in HBV-induced HCC. This may hinder management with receptor tyrosine kinase inhibitors, the basis for treatment of advanced HCC.

Vitamin D deficiency (VDD) is a public health problem which affects all human beings including darkskinned subjects. In children, it can cause disabilities associated with skeletal abnormalities such as rickets or stunted growth. VDD is also associated with a significant risk of extra-skeletal, infectious, auto-immune, neoplastic, and cardiovascular diseases. The concentration of 25 (OH) D is currently considered as the best VDD indicator. Whereas VDD has been well studied in Western countries and North America, very few studies have been conducted in sub-Saharan Africa. The aim of this study was to assess the prevalence and risk factors of VDD in children aged between 0 to 59 months. This is a cross-sectional prospective study conducted from August 5, 2019, to November 30, 2020. A total of three hundred children were included in this study, two hundred of whom were malnourished and the rest with a normal P/T ratio. The variables studied were vitamin D, serum calcium, magnesium, phosphorus and iron. Ferritin, haemoglobin, protein, albumin and prealbumin were also studied. The prevalence of VDD in the general population was 30%. No significant statistical difference in vitamin D concentration values was noticed between malnourished and nourished children with p = 0.388. Children over 24 months of age are 2.34 times more likely to be VDD than others. Given the prevalence of VDD in the study population, it would be necessary to integrate screening and supplementation into current medical practice.