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Streptococcus pyogenes (GAS) is one of the major human pathogenic bacteria that cause a wide range of diseases. Currently, increased incidence of streptococcal invasive infections is observed worldwide. In this study, we focused on the prevalence of genes encoding superantigens and type M proteins in the population of GAS strains from invasive versus non-invasive infections. We tested 253 GAS strains: 48 strains from patients with invasive infections (18 from wound/deep skin localization, 30 from women in labour) and 205 strains from non-invasive forms (147 from common infections of the upper respiratory, 49 from the vagina of females with genital tract infections and 9 from non-invasive wound and superficial skin infections). Significant differences were found in the occurrence of genes: speG, speI, speJ and smeZ, which were more common in GAS isolated from invasive than from non-invasive strains; speJ and smeZ occurred more frequently in strains from invasive perinatal infections versus strains from women without symptoms of invasive infection; speH and speI in strains from invasive skin/wound infection versus strains isolated from non-invasive wound and superficial skin infections. Emm types 1 and 12 predominated in the group of strains isolated from superficial infections and type 28 in those from puerperal fever. Occurrence of genes encoding virulence factors is common in genomic DNA of most of S. pyogenes, regardless whether these streptococcal infections are invasive or non-invasive. On the other hand, it appears that strains with speG, speI, speJ and smeZ genes may have a particular potential for virulence. [ABSTRACT FROM AUTHOR]

Clin Microbiol Infect 2010; 16: 1442–1447 The present study reports the epidemiological investigations undertaken in one of Krakow’s city hospitals regarding the source of infection and the routes of transmission of a group A streptococcus ( Streptococcus pyogenes), using fluorescent in situ hybridization as a rapid method for detecting S. pyogenes carriage in the medical personnel involved. Four patients from the gynaecology department and two patients from the surgery department presented with clinical signs of infection. Characteristics of the S. pyogenes strains isolated from patients and from one medical staff member, including the emm gene and superantigens encoding genes, are described. All patients (four confirmed and two probable cases) survived; the operating theatre aid was identified as an S. pyogenes carrier and the source of the infections. [ABSTRACT FROM AUTHOR]

Background: Sepsis in low-birth-weight neonates remains one of the most significant causes of neonatal morbidity and mortality. Approximately 3 million newborns suffer from sepsis globally every year. The aim of this study was to compare demographic and clinical features, as well as etiology and antibiotic susceptibility, of the main pathogens related to neonatal sepsis in two neonatal intensive units during a two-year period. Methods: We observed early-onset (EO-BSI) and late-onset bloodstream infections (LO-BSI) cases in two high-reference neonatal intensive care units (NICU) over a 24-month period (2016–2017). Samples of patients' blood were tested for the presence of the microorganisms. All bacterial isolates were tested for susceptibility to antibiotics. Results: The majority of sepsis cases weighed above 1000 g and were born by cesarean section. About 10% of the EO-BSI group died. There were differences in the EO-BSI /LO-BSI ratio in the compared wards due to differences among the admitted children. The most common pathogens isolated from blood were coagulase-negative staphylococci (CoNS) were represented by two dominating species: S. epidermidis and S. haemolyticus, followed by Klebsiella spp. strains and E.coli, which were mostly found in EO-BSI cases. No single S. agalactiae (GBS) strain was isolated. The majority of CoNS strains were resistant to methicillin, half were resistant to aminoglycosides, and one-third were resistant to macrolides and lincosamides. Half of the Gram-negative rods were resistant to beta-lactams. Conclusions: The epidemiology of sepsis in two observed NICUs is comparable to data obtained from other studies with a predominance of methicillin-resistant CoNS in LO-BSI and beta-lactam resistant E. coli in EO-BSI. It is of importance that the campaign for controlling GBS carriage in pregnant women in Poland resulted in the disappearance of GBS as a cause of sepsis. Unfortunately, there are no such measures to control E.coli related sepsis. [ABSTRACT FROM AUTHOR]

Presents the results of a study on the differences in tire response due to excitations across the tread width using modal impact testing and transmissibility analysis. Identification of the radial modes of vibration using frequency response function data for impacts on the center tread and response measurements along the center tread; Technique for increasing the frequency bandwidth of the modal impact excitation.

Invasive group A streptococcal (GAS) infections constitute an important epidemiological problem. Many cases occur in women during the postnatal period. The objective of this study was to evaluate the presence of the genes responsible for production of iron-chelating protein (perR) and superantigens (speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ, and ssa) in S. pyogenes strains isolated from invasive infections in women after delivery. Furthermore, this study sought to verify whether S. pyogenes strains show special phenotypic and genotypic (sla, spy1325) characteristics that may play a decisive role in adherence to the genital tract epithelium. Moreover, the emm-types and antibiotic susceptibility were determined. We tested 30 invasive S. pyogenes strains isolated from postpartum invasive infection and 37 GAS control strains isolated from the genital tracts of asymptomatic multiparous women. The majority of the tested strains were shown to express two types of emm genes (1 and 28), though emm −12, −28, −75 and −89 were uniquely expressed in the group of strains isolated from invasive infections. A significantly higher prevalence of perR in the strains from puerperal fever was shown. Significant differences were also found between the two groups with respect to the incidence of the genes related to adherence; GAS strains originating from women with sepsis/puerperal fever showed presence of these genes less frequently than those of the control group. Although differences in frequencies of the gene coding for various superantigens were noted between the compared groups of GAS strains, they were not significant. [ABSTRACT FROM AUTHOR]

Chronic active colitis (including inflammatory bowel disease – IBD) is maintained by a variety of pro-inflammatory mediators. Certain intestinal bacterial strains may induce colitis, whereas some strains (e.g. Lactobacillus spp.) show a protective effect in colitis owing to their anti-inflammatory activity. In this study, we have examined the production of selected inflammatory cytokines, reactive oxygen species (ROS), nitric oxide (NO) and the expression of haeme oxygenase-1 (HO-1) by murine peritoneal macrophages stimulated in vitro by the intestinal bacterial strains, isolated from mice with colitis. Lactobacillus strains ( Lactobacillus reuteri, L. johnsonii, L. animalis/ murinus) and two potentially pathogenic bacteria ( Escherichia coli and Enterococcus faecalis) induced the production of substantial amounts of cytokines with a strain specific profile. Despite some interstrain differences, all lactobacilli induced production of anti-inflammatory cytokines (IL-10high, IL-6low, IL-12p70low). Conversely, E. faecalis and E. coli induced the production of proinflammatory cytokines (TNF- α, IL-12p70), the cytokines essential for chronic IBD. Macrophages released comparably substantial amounts of ROS in response to all Lactobacillus strains tested, while E. coli and E. faecalis ability to induce generation of ROS was negligible. In contrast to ROS, the production of NO/NO2− by macrophages activated with all bacterial strains tested was similar. Moreover, for the first time, it has been shown that intestinal bacteria differed in their ability to induce expression of HO-1, a stress-inducible enzyme with antioxidant and anti-inflammatory properties. The beneficial immunoregulatory properties of candidate probiotic bacteria for the treatment of IBD are discussed. [ABSTRACT FROM AUTHOR]

Background Multiple studies document that probiotics are effective in treating infectious diarrhoea in children. Lactobacillus rhamnosus GG is the most extensively studied but effectiveness of other strains has been poorly examined. Aim To determine whether L. rhamnosus strains (573L/1; 573L/2; 573L/3) (Lakcid L, Biomed, Lublin, Poland) would be effective in shortening infectious diarrhoea. Methods In a randomized, double-blind, placebo-controlled trial, 87 children (age range: 2 months to 6 years) with infectious diarrhoea were administered Lakcid L at a dose 1.2 × 1010 CFU or placebo, twice daily, for 5 days. Primary outcome measure was the duration of diarrhoea. Secondary measures were duration of parenteral rehydration, adverse events, and gastrointestinal tract colonization by administered strains. Results In an intention to treat analysis of 87 children, the mean duration of diarrhoea in the treated group: 84 ± 56 h; placebo: 96 ± 72 h ( P = 0.36). In rotavirus infection: 76 ± 35 h vs. 115 ± 67 h ( P = 0.03), respectively. Duration of parenteral rehydration: 15 ± 14 h vs. 38 ± 33 h ( P = 0.006). Gut colonization by administered strains was 80% and 41% at five and 14 days, respectively. No adverse events were noted. Conclusions Administration of L. rhamnosus strains shortens the duration of rotaviral diarrhoea in children but not of diarrhoea of any aetiology. Intervention shortens the time of intravenous rehydration. [ABSTRACT FROM AUTHOR]