Journal of Advances in Biology & Biotechnology

Oral cancer is one of the highly prevalent cancers worldwide and a leading cause of mortality in certain regions like South-Central Asia. Oral cancer in Sudan constitutes a serious health problem, squamous cell carcinoma (SCC) is the most prevalent type of oral malignancy. The aim of this study was to assess cellular proliferative activity of clinically healthy oral mucosal epithelial cells of toombak dippers by means of AgNOR counts and cytological atypia using H&E and Pap stain, to find out the best staining results of the three stains, and to find out the most affected age group, frequency of dipping toombak per day, and the effect of snuffing duration in cellular proliferative activity. Smears were collected from normal-appearing mouth floor mucosa and tongue from 100 patients of toombak dippers, 50 non-tobacco users for negative controls and 10 cases were toombak users and they had oral cancer for positive control. AgNORs were counted in the first 50 well-fixed, nucleated squamous cells via microscope. The laboratory analysis showed that; decreasing the number of the normal cases associated with increasing to snuffing duration and to frequency of dipping per day; that the normal cytological appearance was 25 cases of snuffing duration of 2-5 years, 20 cases of snuffing duration of 6-10 years, and 4 cases of 11-15 years of snuffing. Increasing in the cases of inflammation associated with increasing to snuffing duration and to frequency of dipping per day; that the inflamed samples was 3 cases of snuffing duration of 2-5 years, 15 cases of 6-10 years of snuffing, 16 cases in 11-15 years, in 16-20 years were 8 cases, and 3 cases in above 20 years of snuffing. The cases of a typical cells appears associated in cells appears associated with increasing to snuffing duration after 11-15 years of snuffing and to increasing in frequency of dipping per day. The AgNor number like the cytological diagnosis of H&E and Pap stain that the normal count found in short snuffing duration and the abnormal count appears with the increasing in snuffing duration after 11-15 years of snuffing, as general alteration in oral mucosa appears after 5 years and more than 5 times/day, the difference was statistically significant (P value 0.01), and associated with increasing in frequency of dipping per day. In conclusion oral exfoliative cytology using Pap and H&E stain is useful in evaluation of epithelial a typia that is frequently encountered with pre-malignant and early malignant oral lesions. The results in AgNor count like the cytological diagnosis in H&E and Pap stain, the intensive exposure to toombak is a significant factor of increasing cellular  a typia. The study recommended that there is a need to standardize the cytological proliferative marker methods to provide rapid, inexpensive, simple and applicable screening test for subjects who have been identified as being at high risk for developing oral cancer, therefore the micro nuclei frequency and AgNOR counts recommended to being used with Pap and H&E stain.

The microbiological properties and population dynamics of atmosphere in mesotidal estuarine of Iko River were investigated using standard microbiological and analytical procedures. The results revealed that the densities of culturable microbes in the estuary were influenced by tidal regimes. Their abundance varied between both tides as well as locations. Proportionately more fungal isolates were found in the estuarine air. There was a significant positive correlation (r = 0.717, p < 0.05) between the total heterotrophic bacteria in the atmosphere and wind speed, and between the fungi in the atmosphere and wind speed (r = 0.799) during high tide, indicating that increase in wind speed resulted in a corresponding effect in heterotrophic bacterial and fungal counts during high tide. A comparison of the relation between atmospheric temperature and microbial load showed little or no correlation (r =0.30). The results of the air quality attributes of Iko Estuary during low tide and high tide showed that the quality of air in the estuarine environment was affected. The air quality in the estuarine environment was relatively "clean" and wholesome as most criteria gaseous pollutants (HCN, NO_2, SO₂) except CO and SPM were below detectable limits and within the FMENV and WHO acceptable limits. However, the recorded levels of CO in some parts of the fishing settlement were above Federal Ministry of Environment (FMEnv) limits of 10.0 - 20.0 ppm for daily average of 8 hourly values in Nigeria. The levels of atmospheric contaminants varied between low and high tides. The 2.0 ppm level of SPM recorded during high tide is higher than the FMEnv limits of 0.25ppm and is dangerous. The study has revealed significant emission of CO from the fish smoking activity which is common in the settlements. Geographic Information System (GIS) models of microbial communities revealed marked variation which ranged between tidal influences and microhabitats. The model revealed high concentrations of microorganisms in the north-west zone during both tides, while fungi were highly concentrated in the north-east zone during high tide. High species richness was observed, but with little or no tidal influences and isolates included known pathogenic species. The findings revealed that tidal bars and flats in shallow mesotidal estuary are subject to the action of tidal currents and waves. These complex events give rise to large variations in microbial communities in estuarine microhabitats which may be harnessed for effective environmental monitoring.

Genetic Diversity of Common Bean (Phaseolus vulgaris) Cultivars from Different Origins Revealed by Microsatellite Markers

Genetic diversity in 20 common bean genotypes belonged to different sources were studied using with 9 microsatellite (SSR) markers. The 9 SSR loci analyzed produced 32 alleles with an average 3.5 alleles per marker. The number of alleles ranged from 2 to 5, whereas the minimum and maximum alleles were observed in BM156 and BM199, respectively. The effective allelic number (ne) ranged from 1.11 (BM156) to 3.89 (BM199) with an average of 2.3. The He values ranged from 0.29 to 0.61 with an average of 0.39. The PIC values of SSR primer pairs ranged from 0.37 (BM154) to 0.68 (BM199) with an average of 0.47. Cluster analysis clearly delineated the genotypes in four major clusters. Iranian cultivars showed very distinct pattern from other genotypes, while genotypes from Turkey and Iraq grouped very close to each other. Results of principle co-ordinate analysis (PCoA) analysis showed that most of the cultivars are separated by the first or second PCoA, which demonstrated distinct groups of cultivars corresponding to cluster analysis. The high diversity among common bean genotypes from diverse gene pools suggests that cross breeding among these different regions will accelerate the process of diverse germplasm creation and broaden germplasm resources in common bean.

In silico Phylogenetics and Molecular Docking Studies of Rhodanese from Yeast (Saccharomyces cerevisiae)

Aim: To evaluate the in silico phylogenetics, binding energy and poses of rhodanese from Yeast (Saccharomyces cerevisiae) with known substrates and inhibitors.

Study Design: The three categories of ligands which include substrates, salts and effectors, were used against the phylogenetically conserved rhodanese from yeast.

Place and Duration of Study: The study was carried out at the Enzyme Biotechnology and Bioinformatics Unit, Department of Biochemistry, Federal University of Technology Akure, Nigeria. The research was carried out from January to March 2018.

Methodology: The properties of rhodanese from S. cerevisiae was evaluated using EMBOSS server, phylogeny was constructed through Blastp and ClustalO server, and molecular docking was carried out using AutoDock Tools and AutoDock Vina software.

Results: Evolutionary divergence was observed for two rhodanese (RDL1 and RDL2) from two gene loci of yeast, with different active site amino acid residues that showed deletion of ten amino acids residues during paralogue event, and optimum pH of 5 and 9 respectively.RDL2 was further analyzed based on the sequence length, phylogeny and the characteristic of the active site similar to previous experimental reports on rhodaneses. The binding energy obtained from molecular docking were -3.0, -5.2, -5.7, -4.2, -2.5, and -1.1 kcal/mol for thiosulphate, sodium metabisulphite, EDTA, ascorbic acid, MgCl₂ and ammonium persulphate respectively. However, it was observed that yeast rhodanese (RDL2) has three other binding domains apart from its active site, that functions in pre-catalysis, ionic sensitivity and acid-base sensitivity for other sulphur-containing substrates, salts and other agents respectively.

Conclusion: This study provides an insight to the mechanism of rhodanese by showing the presence of a critical catalytic cysteine residue and the relationship that possibly exists between the catalytic site and other allosteric sites, and that pre-catalysis occur for sulphur-containing substrates.

Application of Biological Methods in the Remediation of Oil Polluted Environment in Nigeria

The application of biological methods have been used to remediate oil contaminated land, to promote health and safety of our environments. These biological processes of remediation may be affected by use of single or a combination of approaches. These processes include to degrade, break down, transform, and/or essentially remove contaminants or impairments of quality from soil and water, otherwise known as bioremediation.  Bioremediation is a natural process which relies on bacteria, fungi, and plants to alter contaminants as these organisms carry out their normal life functions. Metabolic processes of these organisms are capable of using chemical contaminants as an energy source, rendering the contaminants harmless or less toxic products in most cases. This paper is a review of the biological methods used in the remediation process.