Photothermal-assisted antibacterial application of graphene oxide-Ag nanocomposites against clinically isolated multi-drug resistant Escherichia coli.

In the field of public health, treatment of multidrug-resistant (MDR) bacterial infection is a great challenge. Herein, we provide a solution to this problem with the use of graphene oxide-silver (GO-Ag) nanocomposites as antibacterial agent. Following established protocols, silver nanoparticles were grown on graphene oxide sheets. Then, a series of in vitro studies were conducted to validate the antibacterial efficiency of the GO-Ag nanocomposites against clinical MDR Escherichia coli (E. coli) strains. GO-Ag nanocomposites showed the highest antibacterial efficiency among tested antimicrobials (graphene oxide, silver nanoparticles, GO-Ag), and synergetic antibacterial effect was observed in GO-Ag nanocomposites treated group. Treatment with 14.0 µg ml-1 GO-Ag could greatly inhibit bacteria growth; remaining bacteria viabilities were 4.4% and 4.1% for MDR-1 and MDR-2 E. coli bacteria, respectively. In addition, with assistance of photothermal effect, effective sterilization could be achieved using GO-Ag nanocomposites as low as 7.0 µg ml-1. Fluorescence imaging and morphology characterization uncovered that bacteria integrity was disrupted after GO-Ag nanocomposites treatment. Cytotoxicity results of GO-Ag using human-derived cell lines (HEK 293T, Hep G2) suggested more than 80% viability remained at 7.0 µg ml-1. All the results proved that GO-Ag nanocomposites are efficient antibacterial agent against multidrug-resistant E. coli.

MTHFR 677C>T and 1298A>C polymorphisms and male infertility risk: a meta-analysis.

Epidemiological studies have evaluated the association between MTHFR 677C>T and 1298A>C polymorphisms and risk of male infertility. However, the results from the published studies on the association between these two MTHFR polymorphisms and male infertility risk are conflicting. To derive a more precise estimation of association between the MTHFR polymorphisms and risk of male infertility, we performed a meta-analysis. A comprehensive search was conducted to identify all case-control studies of MTHFR polymorphisms and male infertility risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Overall, we found that both 677C>T and 1298A>C polymorphisms were not significantly associated with male infertility risk. However, in stratified analysis by ethnicity, we found that the 677C>T polymorphism was significantly associated with the risk of male infertility in Asian population (TT vs. CC: OR = 1.57, 95% CI: 1.05-2.37, P = 0.03; TT vs. TC + CC: OR = 1.40, 95% CI: 1.05-1.86, P = 0.02; TT + TC vs. CC: OR = 1.34, 95% CI: 1.01-1.77, P = 0.04). Although some modest bias could not be eliminated, this meta-analysis suggested that the MTHFR 677T allele might be a low-penetrant risk factor for male infertility, especially in Asian population.

[Effect of transrectal prostatic biopsy on serum prostate specific antigen levels].

OBJECTIVES: To assess the effect of transrectal prostatic biopsy (TPB) on the concentrations of serum prostate specific antigen (PSA). METHODS: Twenty patients with abnormal PSA levels and/or digital rectal examination (DRE) underwent TPB. Serum PSA levels were measured before TPB and at 0.5 h, 1 week, 1 month after TPB, respectively. RESULTS: The serum PSA levels before TPB and 0.5 h, 1 week, 1 month after TPB were (12.23 +/- 8.62), (34.90 +/- 41.53), (23.59 +/- 20.78) and (11.31 +/- 6.95) micrograms/L, respectively. The serum PSA concentration was significantly higher at 0.5 h after TPB than before (P < 0.05), and then gradually decreased. PSA levels remained higher for at least 1 week in 85% (17/20) patients(P < 0.05), then returned to the baseline at one month after TPB (P > 0.05). CONCLUSIONS: TPB can lead to a dramatic increase of PSA in serum and keep the PSA value high in one week. Then the PSA in serum decreased gradully. Serum PSA level cannot return to baseline until one month after TPB.