Vol 16, No 4 ,2015, African Scientist

The pluripotency of embryonic stem (ES) cells is the result of a highly dynamic equilibrium that is controlled by a complex network of transcription factors that confer unique transcriptional properties to ES cells. Regulation of gene expression appears to correlate with the presence of dual chromatin marks called bivalent domains at the promoters of poised developmental genes. These marks keep differentiation genes silenced but poised and ready to be activated or permanently repressed during differentiation.

A checklist of indigenous pests of cowpea, Vigna unguiculata (L.) at Mokwa, Niger state, Nigeria, and their relative abundance were reported. The impacts of two most commonly used insecticides in the locality, i.e. Dimethoate and Cypermethrin, on cowpea productivity were elucidated. Thirteen insect species were listed, three of which were prominent at the seedling and prereproductive stages. These include: - Ootheca mutabilis, Empoasca dolichi and Medythia quarterna.

Kola is an important cash crop to a significant proportion of Nigerian population who are involved in kola farming, trading and industrial utilization. Research on the improvement of kola productivity and utilization is one of the major mandates of the Cocoa Research Institute of Nigeria (CRIN), where remarkable achievements have been made on kola. CRIN has developed improved Cola nitida hybrids with short maturation period of 5 years and an annual average yield of about 2000 nuts/tree/year.

Pests and diseases have largely contributed to the declining productivity of cocoa in Nigeria. About 25 – 30% loss in yield of cocoa has been attribute to the cocoa mired, Sahlbergella singularis. 17% is lost through the feeding of the cocoa pod borer Characoma strictigrapta while losses attributable to the major disease of cocoa (the black pod disease caused by Phytophtora megakarya) range from 30 – 90% in Nigeria. The estimated farm holdings of peasant farmers account for 90% of the 700,000 hectares of land under cocoa cultivation.

Six acetone extracts of Annona senegalensis root-bark; Tephrosia vogelii root-bark; stem-bark, leaf and seed; Tephrosia candida seed; and two aqueous residue extracts of neem seed kernel and Annona muricata seed kernel were tested for bioactivity against Rasdtrococcus invadens Williams at different concentrations with three replications. The six acetone extracts were highly toxic to adult female R. invadens in the combined mode experiment. T. vogelii stem-bark, followed by its seed; A. senegalensis root-bark and T. candida seeds extracts, was most insecticidal to the mealybug.

Thirteen fixed lines from the cross of FARO 12 and 44 were evaluated at Edozhigi and Gara villages, located in central Nigeria. The trial was conducted to select promising lines to be used for African rice gall midge (AfRGM) and iron toxicity endemic areas. The experiment was randomized complete block design replicated three times. The result showed significant differences in grain yield at Gara but not at Edozhigi. Percentage tiller damage for AfRGM was high in both locations. Iron toxicity score was also moderate for the two locations, however higher scores were obtained at Edozhigi.

A survey of soil transmitted helminthes (STH) in different markets of Benin City was carried out using the test-tube floatation method. A total of three hundred (300) samples from different sections of the markets were examined and 82 (27.33%) samples had various geohelminth eggs. The parasite prevalence rates were Ascaris lumbricoides (30.99%), Necator americanus (20.25%), Trichuris trichuria (16.12%), Strongyloides stercoralis (10.33%). The prevalence of these helminth eggs is attributed to indiscriminate disposal of faeces and refuse in and around the markets.

Enzyme-Linked Immunosorbent Assay (ELISA) for the diagnosis of fascioliasis due to F. gigantica was found to be more sensitive for the diagnosis of fascioliasis when compared with Faecal Egg Examination (FEE). An average monthly prevalence of 79.3% was observed for ELISA while FEE gave a prevalence of 28%. This indicates that parasitological methods of diagnosis underestimates parasite prevalence. There is therefore need to use conventional method of diagnosis in association with serological diagnosis.

Microbiological qualities of 32 samples of smoked fish belonging to 4 species of fish namely: Clarias gariepinus, Oreochromis niloticus, Citharinus citharus and Synodontis membranaceous; from four (4) local markets (Monday Market, Sabo Market, Malale Market, Awuru Market) were studied. In most samples, moisture contents were high, 53.12% of the fish samples have moisture content above 30% level. The smoked samples were dominated by gram-positive bacteria however, potential pathogens, coagulase positive staphylococci, and Escherichia coli were isolated from some of the samples.

The presence of Gallstones in the gallbladder is known to cause irritation of the gallbladder wall thereby resulting in the thickening of the gallbladder wall. On the other hand, an inflamed gallbladder, with its thickened wall, has been postulated to encourage super-saturation of gallbladder bile and subsequent gallstone formation. This study was therefore designed to determine the relationship between the presence of Gallstones and Gallbladder wall thickness.