ABSTRACT
Heavy metals, generally characterized by high densities and atomic weights, are ubiquitous in the environment and are a public health concern due to the several health issues they pose to humans. Of all heavy metals, lead and cadmium among others are known to be capable of inducing multiple health effects even at a low rate of exposure. Hypertension (HYP), a major cause of death and a risk factor for other cardiovascular diseases, is known to be caused by both lead and cadmium. While the mechanism underlying the development of HYP induced by independent exposure to lead and cadmium has been well studied, the mechanism underlying the induction and progression of HYP upon lead and cadmium co-exposure remains mildly explored. Hence, this study aimed to elucidate the mechanism using a toxicogenomic approach. The set of genes affected by both heavy metals was identified using the comparative toxicogenomics database (CTD) while HYP targets were retrieved from the Gene Cards database. The shared genes between the heavy metals and the disease were identified and subjected to further analysis. The results of our analysis revealed the signaling pathways that are dysregulated by lead and cadmium co-exposure while oxidative stress, inflammation, and endothelial dysfunction were revealed as processes pertinent to the induction and progression of HYP by lead and cadmium co-exposure. Biomarkers that could be used for prognosis evaluation were also identified. Ultimately, this study supports and advances the growing body of finding on the roles played by lead and cadmium co-exposure in inducing HYP.
ABSTRACT
Aim: This study aimed at determining the molecular and conventional identities of bacteria associated with presumptive typhoid fever patients in Ondo State, Nigeria. Study Design: The study attempted a comparative study of the conventional and molecular identities of bacteria isolated from presumptively diagnosed typhoid patients. Place and Duration of the Study: The study was conducted in three different hospitals in Ondo State, Nigeria viz; State Specialists’ Hospital, Akure, Don Bosco Clinic, Akure and Federal Medical Centre, Owo, between February and May, 2013. Methodology: A total of 520 blood samples were collected from presumptively diagnosed typhoid fever patients attending Don Bosco Clinic Akure, Federal Medical Center, Owo and State Specialists’ Hospital, Akure, Ondo State, Nigeria. The samples were screened for the presence of Salmonella typhi and other co-existing bacteria through blood culture. Initial identification of the isolates was carried using their culture morphology, Gram stain and biochemical tests, while their identities were verified using molecular techniques like PCR analysis, gene sequencing and blasting. The genetic relatedness of the bacterial isolates was investigated by constructing a phylogenetic tree using neighbor-joining (NJ) method. Results: The traditional identities of the bacteria were Salmonella typhi, Escherichia coli, Staphylococcus aureus, Shigella flexneri, Klebsiella pneumoniae, Enterobacter aerogenes, Serratia marcescens and Pseudomonas aeruginosa while their molecular identities were Enterobacter cloacae, Shigella flexneri, Enterococcus casseliflavus, Achromobacter xylosoxidans, Bacterium species clone BAO 14, Serratia marcescens and Pseudomonas aeruginosa respectively. Most of the isolates fell within the same clade on the phylogenetic tree signifying that they had a common ancestor. Conclusion: Molecular biology techniques are more reliable, sensitive and accurate for bacterial identification than the conventional methods.