RESUMO
Bacteriophages (phages) are capable of infecting specific bacteria, and therefore can be used as a biological control agent to control bacteria-induced animal, plant, and human diseases. In this study, two homolog phages (named PPAY and PPAT) that infect Pseudomonas aeruginosa PAO1 were isolated and characterized. The results of the phage plaque assay showed that PPAT plaques were transparent dots, while the PPAY plaques were translucent dots with a halo. Transmission electron microscopy results showed that PPAT (65 nm) and PPAY (60 nm) strains are similar in size and have an icosahedral head and a short tail. Therefore, these belong to the short-tailed phage family Podoviridae. One-step growth curves revealed the latent period of 20 min and burst time of 30 min for PPAT and PPAY. The burst size of PPAT (953 PFUs/infected cell) was higher than that of PPAY (457 PFUs/infected cell). Also, the adsorption rate constant of PPAT (5.97 × 10-7 ml/min) was higher than that of PPAY (1.32 × 10-7 ml/min) at 5 min. Whole-genome sequencing of phages was carried out using the Illumina HiSeq platform. The genomes of PPAT and PPAY have 54,888 and 50,154 bp, respectively. Only 17 of the 352 predicted ORFs of PPAT could be matched to homologous genes of known function. Likewise, among the 351 predicted ORFs of PPAY, only 18 ORFs could be matched to genes of established functions. Homology and evolutionary analysis indicated that PPAT and PPAY are closely related to PA11. The presence of tail fiber proteins in PPAY but not in PPAT may have contributed to the halo effect of its plaque spots. In all, PPAT and PPAY, newly discovered P. aeruginosa phages, showed growth inhibitory effects on bacteria and can be used for research and clinical purposes.
RESUMO
Objective A kind of quantitative C reactive protein (CRP) test kit was developed with colloidal gold lateral flow method. Method The kit was prepared with double antibody sandwich technology, and by material optimization and strict process control to improve performance. Quantitative assay was realized by a specialized lateral flow reader. The kit performance was evaluated with series of tests and clinical trial. Results The kit was developed with functional sensitivity≤1 mg/L, linear range 1-200 mg/L, CV<15%and with stability of 12 months. 220 samples clinical trial showed 98.6%of coincidence rate. Pearson Correlation coefficient r is 0.987, which showed no significant difference in performance compare with control kit. Conclusion A quantitative CRP test kit was developed with easy to operating and good stability, Which can be used for point of care testing or laboratory testing.
RESUMO
OBJECTIVE:To determine the oil-water partition coefficients (logP) of rosiglitazone at different pH values by two kinds of methods.METHODS:A shake flask-ultraviolet spectrophotometry method was used to determine plasma concentration of rosiglitazone in water phase and organic phase at variable pH values (0.95,2.0,3.0,4.0,5.07,5.7,6.55,7.06,7.5,8.15,9.21) to calculate logP by using with n-caprylic alcohol-water as simulation system.Above logP values were compared with that calculated by Pallas software.RESULTS:The logP value was lower than 1 when pH value was lower than 4;the logP value was higher than 1 when pH value was ranged from 5 to 9.Measured logP values were in good agreement with that calculated by Pallas software.CONCLUSION:Rosiglitazone exists in the form of hydrochloride salt with good water solubility (pH