Cobamides are a family of enzyme cofactors that include vitamin B12 (cobalamin) and are produced solely by prokaryotes. Structural variability in the lower axial ligand has been observed in cobamides produced by diverse organisms. Of the three classes of lower ligands, the benzimidazoles are uniquely found in cobamides, whereas the purine and phenolic bases have additional biological functions....

the purpose of the present study was to determine the acute toxicity (lc 50 ) of hgcl 2 and cuso 4 in caspian roach ( rutilus caspicus ) and cuso 4 in caspian kutum ( rutilus kutum ). the caspian roach lc 50 values for hgcl 2 at 24, 48, 72, and 96-hrs of exposure, were 0.64, 0.61, 0.42, and 0.28 mg l -1 , respectively, and for cuso 4 were 11.55, 5.08, 2.49, and 1.47 mg l -1 , respectively. the ...

Carcinogenic risk estimation of human exposure to vinyl chloride (VC) was determined by utilizing laboratory animal data on the chronic bioassay of VC, VC pharmacokinetics and VC macromolecular interaction. The impact of these data upon the type of risk VC may pose to humans and the selection of appropriate mathematical models to quantitatively estimate "risk" are discussed. The problem of esti...

The resistance status towards permethrin among the laboratory strain, the permethrin-selected strain and four field strains of Culex quinquefasciatus collected in Kuala Lumpur, Malaysia was determined using three standard laboratory methods: WHO larval bioassay, WHO adult bioassay and biochemical microplate assay. Cx. quinquefasciatus permethrin-selected strain larvae were the least susceptible...

BACKGROUND TSH receptor antibodies (TBII) in Graves' disease (GD) may be TSH receptor stimulating (TSAb) and blocking (TBAb) antibodies. In commercially available assays however, only total TBII titres can be measured, without discriminating between TSAb and TBAb. OBJECTIVE To design a TBII bioassay to detect of TSAb and to correlate TSAb activity with severity of hyperthyroidism in de novo G...

The purpose of the research is to test efficacy different concentrations composite Kenocox against Eimeria spp. oocysts in turkeys a laboratory experiment and under production conditions. Materials methods . anti-Eimeria activity new disinfection agent was tested as compared with phenol two stages. first stage used 2, 4 6% 4% base drug. second bioassay artificial infection young turkeys, conduc...

Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete's urine. AASs of unknown composition will not be detected by these pro...

Laboratory experiments on the evaluation of infectivity of Beauveria bassiana (Bals.) Vuill. to tobacco caterpillar Spodoptera litura Fab. as influenced by two okra varieties. Infectivity of B. bassiana at three concentrations viz. 0.1, 1.0 and 3.0 per cent was evaluated by contaminated food bioassay method. In comparison, topical bioassay method was also made. Statistically significant variati...

In this study, we investigated the potential antilarval and antibacterial activity of secondary metabolites of the gorgonians Subergorgia suberosa and Scripearia gracillis from the South China Sea. Fresh specimens of these two gorgonian corals were collected from a shallow reef in Sanya Bay of Hainan Island and extracted with different solvents. Antilarval activity of the chemical extracts and ...