SSR marker based DNA fingerprinting and diversity study in rice (Oryza sativa. L)

The genetic diversity and DNA fingerprinting of 15 elite rice genotypes using 30 SSR primers on chromosome numbers 7-12 was investigated. The results revealed that all the primers showed distinct polymorphism among the cultivars studied indicating the robust nature of microsatellites in revealing polymorphism. Cluster analysis grouped the rice genotypes into 10 classes in which japonica types DH-1 (Azucena) and Moroborekan clustered separately from indica types. Principal component analysis was done to visualize genetic relationships among the elite breeding lines. The results were similar toUPGMA results. Based on this study, the larger range of similarity values for related cultivars using microsatellites provides greater confidence for the assessment of genetic diversity and relationships. The information obtained from the DNA fingerprinting studies helps to distinctly identify andcharacterize 9 varieties using 18 different RM primers. This information can be used in background selections during backcross breeding program

Study of Cypermethrin Cytogenesis effects on Human Lymphocytes Using In-Vitro Techniques

The Cytogenetic effects of Cypermethrin a synthetic pyrithroid insecticide was investigated on human lymphocytes cultured in-vitro. Utilizing the trypan blue dye exclusion technique assay the LC50 of cypermethrin was found to be 36 uM. Based on LC50 value, cypermethrin was found to be low toxic to lymphocyte culture. Cypermethrin showed an increase in the frequency of chromosomal aberrations and found to be significant. Karyotype analysis revealed more satellite associations and chromosomal breaks in cypermethrin treated samples. Low-doses of the pesticide also induced singlestrand breaks in the DNA as assessed by comet assay. The pesticide caused increase in the comet tail length with increase in pesticide concentration, implicating genotoxicity in somatic cells. It is concluded that In vitro assays could give important information of the mechanism of toxicity at low dosages and impact on genetic material of human origin

Municipal Wastewater Effluents as a Source of Listerial Pathogens in the Aquatic Milieu of the Eastern Cape Province of South Africa: A Concern of Public Health Importance

We evaluated the effluent quality of an urban wastewater treatment facility in South Africa and its impact on the receiving watershed for a period of 12 months. The prevalence and antimicrobial susceptibility of potential Listeria pathogens (L. ivanovii and L. innocua) and the physicochemical quality of the treated wastewater effluent was assessed, with a view to ascertain the potential health and environmental hazards of the discharged effluent. Total listerial density varied between 2.9 × 100 and 1.2 × 105 cfu/mL; free living Listeria species were more prevalent (84%), compared to Listeria species attached to planktons (59–75%). The treated effluent quality fell short of recommended standards for turbidity, dissolved oxygen, chemical oxygen demand, nitrite, phosphate and Listeria density; while pH, temperature, total dissolved solids and nitrate contents were compliant with target quality limits after treatment. The Listeria isolates (23) were sensitive to three (15%) of the 20 test antibiotics, and showed varying (4.5–91%) levels of resistance to 17 antibiotics. Of seven resistance gene markers assayed, only sulII genes were detected in five (22%) Listeria strains. The study demonstrates a potential negative impact of the wastewater effluent on the receiving environment and suggests a serious public health implication for those who depend on the receiving watershed for drinking and other purposes

<i style="">In vitro</i> cytogenetic studies of cypermethrin on human lymphocytes

233-239Assessment of cytotoxicity and response to external factors like pesticides were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) or MTT assay, which measures mitochondrial metabolism in the entire cell culture and provides information about the percentage of cell survival. Utilizing the MTT assay, the cytotoxicity of cypermethrin was determined on lymphocyte cultures from human peripheral blood samples, the short-term lymphocyte cultures were incubated with various aliquots of the cypermethrin and the LC50 was found to be 33.6 M. Lymphocytes treated with low-doses (1/10 of LC50) of cypermethrin showed an increase in the frequency of chromosomal aberrations and found to be significant. Karyotype analysis revealed more satellite associations and chromosomal breaks in cypermethrin treated samples. Low-doses of the pesticide also induced single-strand breaks in the DNA as assessed by comet assay. The pesticide caused increase in the comet tail length with increase in pesticide concentration, implicating genotoxicity in somatic cells. It is concluded that In vitro assays could give important information of the mechanism of toxicity at low dosages and impact on genetic material of human origin

Investigation of monocrotophos toxic effects on human lymphocytes at cytogenetic level

The genotoxic and cytotoxic effects of monocrotophos, an organophosphate insecticide, was investigated on human lymphocytes cultured in vitro. Utilizing the trypan blue dye exclusion technique assay the IC50 (half maximal inhibitory concentration) of monocrotophos was found to be 16 M. Based on IC50 value, monocrotophos was found to be highly toxic to lymphocyte culture. Chromosomal aberrations induced by monocrotophos were determined using karyotyping. The analysis revealed that more satellite associations, breaks and gaps were found which were statistically significant (P < 0.05) when compared to controls. Comet assay was used to assess the possibility of monocrotophos induction of DNA damage where the increase in comet tail length relates to the extent of DNA single strand breaks. These results indicate that in vitro assays could be used as indicators of cyto- and genotoxic effects of the pesticide on humans, and their end points could be used as biomarkers

Study of Cypermethrin Cytogenesis effects on Human Lymphocytes Using In-Vitro Techniques

The Cytogenetic effects of Cypermethrin a synthetic pyrithroid insecticide was investigated on human lymphocytes cultured in-vitro. Utilizing the trypan blue dye exclusion technique assay the LC50 of cypermethrin was found to be 36 uM. Based on LC50 value, cypermethrin was found to be low toxic to lymphocyte culture. Cypermethrin showed an increase in the frequency of chromosomal aberrations and found to be significant. Karyotype analysis revealed more satellite associations and chromosomal breaks in cypermethrin treated samples. Low-doses of the pesticide also induced singlestrand breaks in the DNA as assessed by comet assay. The pesticide caused increase in the comet tail length with increase in pesticide concentration, implicating genotoxicity in somatic cells. It is concluded that In vitro assays could give important information of the mechanism of toxicity at low dosages and impact on genetic material of human origin