Neurobehavioral and cytotoxic effects of vanadium during oligodendrocyte maturation: a protective role for erythropoietin

Vanadium exposure has been known to lead to lipid peroxidation, demyelination and oligodendrocytes depletion. We investigated behaviour and glial reactions in juvenile mice after early neonatal exposure to vanadium, and examined the direct effects of vanadium in oligodendrocyte progenitor cultures from embryonic mice. Neonatal pups exposed to vanadium via lactation for 15 and 22 days all had lower body weights. Behavioural tests showed in most instances a reduction in locomotor activity and negative geotaxis. Brain analyses revealed astrocytic activation and demyelination in the vanadium exposed groups compared to the controls. In cell culture, exposure of oligodendrocytes to 300 μM sodium metavanadate significantly increased cell death. Expression of the oligodendrocyte specific proteins, 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and oligodendrocyte specific protein (OSP/Claudin) were reduced upon vanadium treatment while simultaneous administration of erythropoietin (EPO; 4-12 U/ml) counteracted vanadium-toxicity. The data suggest that oligodendrocyte damage may explain the increased vulnerability of the juvenile brain to vanadium and support a potential for erythropoietin as a protective agent against vanadium-toxicity during perinatal brain development and maturation.

The burden of anaemia and associated factors in HIV positive Nigerian women

BACKGROUND

Anaemia is the most common complication of pregnancy and a predictor of poor maternal and foetal outcomes. HIV infection is now recognized as one of the major contributors to anaemia in pregnancy. It is therefore important to determine the burden and risk factors of anaemia in maternal HIV infection in others to plan effective prevention strategies as well as optimize management outcomes.

OBJECTIVE

To determine the prevalence and risk factors of anaemia in pregnant HIV positive Nigerians.

METHODS

The prevalence and possible risk factors of anaemia were investigated in HIV positive pregnant Nigerian women at a large HIV treatment clinic in southwestern Nigeria using a cross-sectional design between January 2006 and December 2011.

RESULTS

Nine hundred and eighty-five (42.5 %) women of 2,318 HIV positive pregnant women seen during the period were anaemic by WHO standard defined by haemoglobin <11 g/dl. Majority were of mild to moderate severity (97.9 %). Short inter birth interval (p = 0.002), presence of opportunistic infections (OIs), (p = 0.001), use of zidovudine containing regimen (p = 0.0005) and CD4 cell count <200 cells/mm(3) (p = 0.001) were found to be independently associated with anaemia in HIV positive pregnant women after controlling for confounding variables.

CONCLUSION

Anaemia was found to be high at 42.5 % among the HIV positive women studied and was found to be independently associated with short inter birth interval, presence of OIs, advanced HIV disease and use of zidovudine containing HAART regimen.

Developing a community-based maternal obesity intervention: a qualitative study of service providers' views

The aim of this study was to explore healthcare professionals' views on the development of multicomponent interventions for obese pregnant women. A cohort of 22 healthcare professionals was interviewed. The interview transcripts were analysed thematically. Three key themes were highlighted by the interviews: (1) the lack of existing services for obese pregnant women in south-east London; (2) the barriers and challenges that need to be overcome (e.g. ethnic and cultural) when considering the creation of a new service for obese women who are pregnant; (3) the possible components of a new intervention. The findings of this study will inform the design of a programme to combat maternal obesity.

Identification of a single nucleotide polymorphism in the TATA box of the CYP2A6 gene: impairment of its promoter activity

Human cytochrome P450 2A6 (CYP2A6) constitutes the major nicotine oxidase, and large interindividual differences are seen in the levels of this enzyme, to a great extent caused by the distribution of several different polymorphic gene variants mainly located in the open reading frame (ORF). In the present study, we report a common polymorphism located in the 5' flanking region of CYP2A6 affecting its expression. DHPLC analysis and complete sequence of the open reading frame of the gene from a Turkish individual revealed a -48T > G substitution disrupting the TATA box. Using dynamic allele-specific hybridization (DASH), genotyping of this novel variant (named CYP2A6*9) was carried out in 116 Swedish, 132 Turkish, and 102 Chinese subjects, and the allele frequencies were found to be 5.2, 7.2, and 15.7%, respectively. The significance of the polymorphism was investigated by the construction of luciferase reporter plasmids containing 135 or 500 bp of the 5'-upstream region of the gene transfected into human hepatoma B16A2 cells. The constructs carrying the -48T > G mutation were only expressed at about 50% of the wild-type alleles. It is concluded that the CYP2A6*9 allele might be one of the most common CYP2A6 variants in Caucasians that alters the levels of enzyme expression.

GSTT1 null genotype frequency in a Turkish population

In humans, glutathione-S-transferases (GSTs) are involved in the detoxification of xenobiotics. A deletion polymorphism in the glutathione S-transferase Theta 1 gene (GSTT1 null genotype) is associated with an increased risk of certain forms of cancer. The distribution of this polymorphism in 240 healthy individuals has been examined, using a polymerase chain reaction (PCR)-based method. The GSTT1 null genotype frequency was 20% in a Turkish Population.