Aspects of pathogenicity of Streptococcus pyogenes group A

This thesis has sought to characterize some of the factors that influence the production, purification and toxicity of streptolysin S (SLS) from Streptococcus pyogenes group A. Two strains, C203S and 55903M, were examined for the production of SLS. Of these, C203S produced the highest yield. Production of the lysin in brain heart infusion broth (BHI,Difco) supplemented with 1% (w/v) maltose and 2% (w/v) sodium bicarbonate (BHI-BM), was maximal between the early and late exponential phases of growth. SLS production was examined in both strains grown in BHI-BM (Oxoid) and BHI-BM (Difco). Cultures in the latter medium gave the higher yields of SLS. For intensive production of SLS, a procedure involving fourteen "inductions" was carried out on the same pellet of bacteria, which was repeatedly resuspended in induction buffer and stimulated each time with RNA-core, SLS was synthesized de novo during each induction cycle, and inhibitors of protein synthesis such as chloramphenicol blocked its formation. The combined material from the 14 inductions (crude SLS) was further purified by hydroxylapatite column chromatography. The purified product had a specific activity of 3.5X10

Surgical site infections, international nosocomial infection control consortium (INICC) report, data summary of 30 countries, 2005-2010

10.1086/670626Infection Control and Hospital Epidemiology346597-604ICEP

International Nosocomial Infection Control Consortiu (INICC) report, data summary of 43 countries for 2007-2012. Device-associated module

We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care–associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line–associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN