Sero-prevalence of HIV antibodies in pregnant women in Port Harcourt, Nigeria.

BACKGROUND: The aim of the study was to determine the Sero-Prevalence of HIV antibodies in pregnant women attending the antenatal clinic at the University of Port Harcourt Teaching Hospital, Port Harcourt. METHOD: Serial recruitment of 600 women who attended the antenatal clinic. HIV screening was done by rapid ELISA technique. Positive samples were re-tested with a second rapid ELISA kit, with only samples sero-positive with both kits being taken as trulysero-positive. RESULTS: The sero-positivity rate was 7.3%, sixty-nine point seven percent (69.7%) of all sero-positive cases were primiparae, with 84% in advanced stages of pregnancy (2nd and 31rd trimesters). History of blood transfusion, dental manipulations, tattooing and circumcision did not contribute significantly to increased HIV sero-positivity. CONCLUSION: There is high HIV sero-positivity rate among pregnant women attending antenatal clinic in Port Harcourt. The implications of this finding in relation to vertical transmission, transmission of nosocomial infection and increased occupational exposure of laboratory and hospital staff to HIV infection is discussed. Compulsory routine screening of all pregnant women attending antenatal clinics in Sub-Saharan Africa is advocated.

Tracking monolignols during wood development in lodgepole pine.

Secondary xylem (wood) formation in gymnosperms requires that the tracheid protoplasts first build an elaborate secondary cell wall from an array of polysaccharides and then reinforce it with lignin, an amorphous, three-dimensional product of the random radical coupling of monolignols. The objective of this study was to track the spatial distribution of monolignols during development as they move from symplasm to apoplasm. This was done by feeding [(3)H]phenylalanine ([(3)H]Phe) to dissected cambium/developing wood from lodgepole pine (Pinus contorta var latifolia) seedlings, allowing uptake and metabolism, then rapidly freezing the cells and performing autoradiography to detect the locations of the monolignols responsible for lignification. Parallel experiments showed that radioactivity was incorporated into polymeric lignin and a methanol-soluble pool that was characterized by high-performance liquid chromatography. [(3)H]Phe was incorporated into expected lignin precursors, such as coniferyl alcohol and p-coumaryl alcohol, as well as pinoresinol. Coniferin, the glucoside of coniferyl alcohol, was detected by high-performance liquid chromatography but was not radioactively labeled. With light microscopy, radiolabeled phenylpropanoids were detected in the rays as well as the tracheids, with the two cell types showing differential sensitivity to inhibitors of protein translation and phenylpropanoid metabolism. Secondary cell walls of developing tracheids were heavily labeled when incubated with [(3)H]Phe. Inside the cell, cytoplasm was most strongly labeled followed by Golgi and low-vacuole label. Inhibitor studies suggest that the Golgi signal could be attributed to protein, rather than phenylpropanoid, origins. These data, produced with the best microscopy tools that are available today, support a model in which unknown membrane transporters, rather than Golgi vesicles, export monolignols.