Antibacterial effect of bacteriocin XJS01 and its application as antibiofilm agents to treat multidrug-resistant Staphylococcus aureus infection

Multidrug-resistant (MDR) Staphylococcus aureus biofilms have emerged as a serious threat to human health. Recently, the development of antibiotic replacement therapy has gained much attention due to the potential application of bacteriocin. The present study sought to evaluate the antibacterial effect of bacteriocin XJS01 against MDR S. aureus, a previously reported bacteriocin against S. aureus strain 2612:1606BL1486 (S. aureus_26, an MDR strain demonstrated here), and its potential application as an antibiofilm agent. The minimum bactericide concentration of XJS01 against MDR S. aureus_26 was 33.18 μg/mL. XJS01 exhibited excellent storage stability and resistance against acid and reduced the density of established MDR S. aureus_26 biofilm. The hemolytic and HEK293T cytotoxicity activities of XJS01 and the histological analyses in mice confirmed its safety. Moreover, XJS01 effectively disrupted the MDR S. aureus_26 biofilm established on the skin wound surface and reduced the biofilm-isolated bacteria, thereby decreasing the release of pro-inflammatory cytokines and the proliferation of alternatively activated macrophages. Compared to mupirocin, XJS01 exhibited an excellent therapeutic effect on mice skin wounds, confirming it to be a potential alternative to antibiotics.

Racial disparities in the association between diabetes mellitus-associated polymorphic locus rs4430796 of the HNF1β gene and prostate cancer: a systematic review and meta-analysis

Polymorphism 17q12 rs4430796 within HNF1β is a genetic variant associated with both diabetes mellitus and prostate cancer, but findings on the correlations of rs4430796 with prostate cancer risk specifically are not in agreement, especially among diverse populations. To shed some light on the contradictory findings, therefore, we carried out a meta-analysis by pooling the odds ratios (ORs) with corresponding 95% confidence intervals (CIs) of all currently available case-control studies located within PubMed and Embase databases up to December 2012. A total of 16 studies comprising 30 datasets that collectively involved 25,535 prostate cancer patients and 25,726 controls were ultimately included in this analysis. The meta-analysis of all the studies revealed that the rs4430796 polymorphism was significantly associated with an increased risk of prostate cancer in all contrast models (ORA vs G = 1.25, 95%CI = 1.21-1.30, POR < 0.001; ORAA vs GG = 1.53, 95%CI = 1.45-1.62, POR < 0.001; ORAG vs GG = 1.24, 95%CI = 1.16-1.34, POR < 0.001; ORAA vs AG+GG = 1.36, 95%CI = 1.30-1.42, POR < 0.001; ORAA+AG vs GG = 1.37, 95%CI = 1.30-1.44, POR < 0.001). After subgroup analyses stratified by ethnicity, however, the rs4430796 polymorphism was significantly associated with prostate cancer in both Caucasians and Asians but not in African-Americans. In conclusion, our meta-analysis identified a significant association between the 17q12 rs4430796 polymorphism and prostate cancer risk, although the degree of this association and frequency of the causative allele varied among men of different races.

[Study on the subclinical infection of the recipients of measles vaccine]

Through observation to subclinical infection of the 71 children who had been inoculated against measles 12 years ago and then exposed to natural measles from three classes at a primary school, we have noticed: (1) Subclinical infection did exist among the crowd who were inoculation against measles; The rate of subclinical infection of the three classes was between 18.5%-75.0%, with an average of 45.1%. (2) The level of the HI Ab titer was between 1:2-1:16. The peak level was between 1:2 and/or 1:4. So the rate of subclinical infection who had been inoculation against measles but later exposed to natural measles would depend on the proportion of those whose titer of HI Ab was 1:2-1:4 in the crowd. (3) The epidemiological significance of subclinical measles infection lies in that it can actively keep and consolidate the level of immunity to certain extent in a crowd who had been inoculation against measles.

Duration of immunity following immunization with live measles vaccine: 15 years of observation in Zhejiang Province, China

The duration of immunity following measles vaccination of 2882 immunized children has been investigated in a closed region of China for 15 years. A total of 1002 of the children were treated as primary immunization subjects, and 1547 as reimmunization subjects. These two cohorts were not in contact with known wild measles virus over the whole observation period, and the results obtained probably reflected the antibody responses to measles vaccine alone. The remaining 333 vaccinees came into contact with wild measles virus, and this permitted evaluation of the protective effect of the measles vaccines tested: 4 children experienced very mild clinical measles, and 329 experienced subclinical infection, including 12 who had had undetectable haemagglutination-inhibition antibodies for 9-10 years. These results indicate that the immunity induced by successful primary immunization may persist for at least 15 years. Within this period, a second dose of vaccine only induces low antibody responses which decrease rapidly to their original levels. This provides strong evidence that the immunity produced by primary immunization is long-lasting. However, there were some indications that reimmunization might produce better effects if live attenuated measles virus were used with a longer interval between doses.