Inducible expression of FGF2 by a rat oligodendrocyte precursor cell line promotes CNS myelination in vitro

Transplantation of glial cells into the central nervous system (CNS) may be a promising approach for the treatment of myelin disorders such as multiple sclerosis (MS). Myelination by transplantation of oligodendrocyte precursors has been obtained in different animal models of demyelination. A strategy to favor CNS remyelination is to enrich the lesioned areas in growth factors to stimulate the quiescent population of oligodendrocyte precursors. In this context, we have developed a genetically modified CG4 cell line (CG4-FGF2), which are able to release significant amounts of fibroblast growth factor 2 (FGF2) in a controlable fashion in vitro. The data presented here demonstrate that upon induction with Dox, CG4-FGF2 cells retain their capacity to differentiate in vitro. Additionally, we provide evidence that FGF2 release by engineered cells enhance proliferation and migration of cells of the oligodendrocyte lineage without preventing them to differentiate and myelinate axons in vitro.     

LR white post-embedding colloidal gold method to immunostain MBP,P0, NF and S100 in glutaraldehyde fixed peripheral nerve tissue

A variety of immunocytochemical techniques are now widely used for the electron and light microscopic examination of biological samples. They are employed routinely for investigating the role of certain proteins in nervous tissue. Immunoelectron microscopic studies require the tissue to be fixed and embedded in a solid support, which may disrupt cellular structures and destroy crucial antigens. A technique of post-embedding with LR white resin has been developed, and it has been shown that certain antigens tolerate fixation with glutaraldehyde. In this study, we optimized a previous post-embedding method using low-water-miscible low-temperature embedding resin (LR white) to immunostain MBP, P0, NF and S100 proteins in peripheral nerves fixed with a relatively high concentration of glutaraldehyde found to be compatible with the morphology of normally compacted nerve fibers from humans and adult animals. The main difference in the procedures described here from previous ones is the elimination of vibratome sectioning, rendering this immunostaining technique more accessible to neuropathological laboratories using standard equipment for the ultrastructural study of peripheral nerves. It may prove of value for localization and quantification of these proteins in normal and pathological conditions.     

Nationwide HIV prevalence survey in general population in Niger

A national population-based survey was carried out in Niger in 2002 to assess HIV prevalence in the population aged 15-49 years. A two-stage cluster sampling was used and the blood specimens were collected on filter paper and tested according to an algorithm involving up to three diagnostic tests whenever appropriate. Testing was unlinked and anonymous. The refusal rate was 1.1% and 6056 blood samples were available for analysis. The adjusted prevalence of HIV was 0.87% (95% CI, 0.5-1.3%) and the 95% CI of the estimated number of infected individuals was 22 864-59 640. HIV-1 and HIV-2 represented, respectively, 95.6% and 2.9% of infections while dual infections represented 1.5%. HIV positivity rate was 1.0% in women and 0.7% in men. It was significantly higher among urban populations than among rural ones (respectively, 2.1% and 0.6%, P < 10(-6)). Using logistic regression, the variables significantly related to the risk of being tested positive for HIV were urban housing, increasing age and being either widowed or divorced. The estimate from the national survey was lower than the prevalence assessed from antenatal clinic data (2.8% in 2001). In the future, the representativeness of sentinel sites should be improved by increasing the representation of rural areas accounting for more than 80% of the population. Compared with other sub-Saharan countries, the HIV prevalence in Niger is still moderate. This situation represents a strong argument for enhancing prevention programmes and makes realistic the projects promoting an access to potent antiretroviral therapies for the majority.     

Behaviour and HIV seroprevalence investigation in sex workers of Dirkou, Niger, 2002

In the framework of the Human Immunodeficiency Virus (HIV) surveillance, seroprevalence and behavioural survey was conducted in 2002 in Dirkou, a place of concentration of female sex workers (FSW) in Niger The global HIV seroprevalence found was 50% (CI at 95%: 40.6-59.36%). The behavioural survey revealed that 98% of FSW had heard about HIV whereas 78.7% know at least one HIV transmission way and 76.9% know at least one HIV prevention means. Only 33.3% declared using condom, what show that sensitisation efforts are needed to induce a behaviour change in FSW and their clients.     

Switch to second-line ART in West African routine care: incidence and reasons for switching

In sub-Saharan Africa, while antiretroviral therapy (ART) becomes widely available, access to biological measurements to monitor patients under ART remains scarce, making the management of ART difficult. We described the management of switching to second-line ART where HIV care is provided mainly in secondary health-care structures, in the region of Segou, Mali. Of 865 patients, followed under ART for a median time of 15 months, 40 switched to second-line ART (3.3 switches/100 person years). Reason for switching was failure in 18 patients (after 21 months in median) and severe intolerance in 13 (after three months in median). Switching to second-line ART occurred earlier when motivated by intolerance than by failure. The low rate of switch compares well with other studies, but was low compared to the expected rate of failure, and may indicate that physicians are reluctant to switch ART when treatment options are limited.     

Kinetics of maternally-derived serogroup A,C, Y and W-specific meningococcal immunoglobulin G in Malian women and infants

A prospective, randomised, controlled observer-blind trial measuring the efficacy and immunogenicity of trivalent influenza vaccine (TIV) and the immunogenicity of quadrivalent meningococcal conjugate vaccine (MCV) in pregnant women and their infants up to 6?months of age was conducted in Mali. Here we reported the immunogenicity of MCV, which was used as a comparator vaccine to TIV, in this population. Third-trimester pregnant Malian women were randomized to receive TIV or MCV. Blood samples were collected from women prior to vaccination, 28?days post-vaccination, at delivery and 3 and 6?months post-delivery and from infants at birth and 3 and 6?months of age. Meningococcal-specific serogroup (Men) A, C, Y and W-specific antibodies were measured by enzyme linked immunosorbent assay in a randomly selected subset of 50 mother-infant pairs where the mother had received MCV. At birth, 94.0% (47/50) of infants had MenA specific IgG levels?≥?2?µg/mL decreasing to 72.9% and 30.4% at 3 and 6?months of age. For MenC, 81.3% (39/48) of infants had MenC specific IgG levels?≥?2?µg/mL at birth decreasing to 29.4% and 17.8% at 3 and 6?months of age. For MenY, 89.6% (43/48) of infants had MenY specific IgG levels?≥?2?µg/mL at birth decreasing to 64.6% and 62.5% at 3 and 6?months of age. For MenW, 89.6% (43/48) of infants had MenW specific IgG levels?≥?2?μg/ml at birth decreasing to 62.5% and 41.7% at 3 and 6?months of age.Maternal immunization with MCV conveyed protective levels of IgG at birth through to 3?months of age in the majority of infants.     

Effect of ready‐to‐use foods for preventing child undernutrition in Niger: analysis of a prospective intervention study over 15 months of follow‐up

Strategies for preventing undernutrition comprise a range of interventions, including education, provision of complementary food and cash transfer. Here, we compared monthly distributions of two different lipid‐based nutrient supplements (LNS), large‐quantity LNS (LNS‐LQ) and medium‐quantity LNS (LNS‐MQ) for 15 months on prevention of undernutrition among children 6 to 23 months. Both groups also received cash transfer for the first 5 months of the intervention. We conducted a prospective intervention study in Maradi, Niger, between August 2011 and October 2012. Six and 11 villages were randomly allocated to LNS‐LQ/Cash and LNS‐MQ/Cash, respectively. Children measuring 60–80 cm were enrolled in the respective groups and followed up monthly. Poisson regression was used to assess differences between interventions and adjust for baseline characteristics, intervention periods and child‐feeding practices. The analysis included 2586 children (1081 in the LNS‐LQ/Cash group and 1505 in the LNS‐MQ/Cash group). This study suggests that provision of LNS‐LQ (reference) or LNS‐MQ had, overall, similar effect on incidence of severe acute malnutrition (RR = 0.97; 95% CI: 0.67–1.40; P = 0.88), moderate acute malnutrition (RR = 1.20; 95% CI: 0.97–1.48; P = 0.08), severe stunting (RR = 0.94; 95% CI: 0.70–1.26; P = 0.69), moderate stunting (RR = 0.95; 95% CI: 0.76–1.19; P = 0.67) and mortality (RR = 0.83; 95% CI: 0.41–1.65; P = 0.59). Compared with LNS‐LQ, LNS‐MQ showed a greater protective effect on moderate acute malnutrition among children with good dietary adequacy: RR = 0.72; 95% CI: 0.56–0.94; P = 0.01. These results highlight the need to design context‐specific programmes. Provision of LNS‐LQ might be more appropriate when food insecurity is high, while when food security is better, distribution of LNS‐MQ might be more appropriate.     

Anti-ulcer polysaccharides from Cola cordifolia bark and leaves

Ethnopharmacological relevance

Aqueous extracts of bark and leaves of C. cordifolia are traditionally used in Mali (West Africa) in the treatment of wounds and gastric ailments like abdominal pain, gastritis and gastric ulcers.

Aim of the study

To evaluate and compare the anti-ulcer and immunological activities, as well as the toxicity of polysaccharide rich water extracts from the bark and leaves of C. cordifolia.

Materials and methods

Gastric ulcers were induced in rats and the inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity was tested on brine shrimps. The two extracts were characterised by GC, Yariv-precipitation and quantification of phenolic compounds. An ethnomedical survey on C. cordifolia was carried out in Siby (Mali, West-Africa) to generate more knowledge about the traditional use.

Results

Bark and leaf extracts from C. cordifolia significantly inhibited the formation of gastric lesions in rodents in a dose depending manner. CCbark50 showed a high complement fixation activity in vitro. No toxicity was found. The ethnomedical survey showed that C. cordifolia was mainly used for treating pain and wounds.

Conclusions

Our results shows that the bark and the leaves comprise a dose dependant anti-ulcer activity in an experimental rat model (no statistical difference between the plant parts). Clinical studies should be performed to evaluate the effect of both bark and leaves of C. cordifolia as a remedy against gastric ulcer in human.     

小儿艾滋病72例临床分析

目的：通过分析小儿艾滋病（AIDS）的临床资料,探讨小儿AIDS的流行病学和临床特点,以预防小儿AIDS的发生。方法：回顾性分析72例小儿AIDS的临床资料,72例患儿用酶联免疫吸附法（ELISA）测人类免疫缺陷病毒（HIV）抗体均为阳性。结果：小儿AIDS患儿以长期反复发热、迁延性咳嗽、腹泻、消瘦合并霉菌和结核感染为主要表现,临床表现无特异性,预后差,病死率为100%。结论：小儿AIDS主要是由感染HIV的育龄妇女经垂直传播而感染,应结合流行病学进一步检测HIV抗体,防止误诊或漏诊,及时有效地阻断母婴传播是预防小儿AIDS发生的关键。