Homology analysis of 51 penicillin-intermediate Streptococcus pneumoniae isolates from Wenzhou City, China.

OBJECTIVE: To investigate drug resistance features and homology among penicillin-intermediate Streptococcus pneumoniae isolates from Wenzhou City, China. METHODS: Fifty-one penicillin-intermediate S. pneumoniae isolates were obtained from respiratory samples of infants and children hospitalized with lung infections. An antimicrobial susceptibility test was used to assess drug resistance. Polymerase chain reaction and agarose gel electrophoresis were used to identify S. pneumoniae isolates and pulsed-field gel electrophoresis (PFGE) was used to analyze molecular subtypes. Hierarchical cluster analysis of PFGE fingerprints was used to compare genetic diversity and relatedness of S. pneumoniae isolates. The Quellung test was used for serotyping. RESULTS: Fifty-one penicillin-intermediate S. pneumoniae isolates showed evidence of multi-drug resistance and polyclonal origins. The isolates were classified into 25 subtypes through hierarchical cluster analysis of PFGE fingerprints. Three of these subtypes formed a supertype (15/51, 16/51 and 8/51 isolates), while the remaining subtypes occurred sporadically (12/51 isolates). CONCLUSIONS: Transmission of penicillin-intermediate S. pneumoniae is mostly vertical and to a lesser extent horizontal. Effective prevention strategies, including respiratory tract management and contact isolation, are essential to control nosocomial S. pneumoniae infection. Once susceptibility is confirmed, vancomycin, high-dose penicillin or third-generation cephalosporins (cefotaxime and ceftriaxone) may be used to treat penicillin-intermediate S. pneumoniae.

Exosomal Long Noncoding RNAs are Differentially Expressed in the Cervicovaginal Lavage Samples of Cervical Cancer Patients.

BACKGROUND: As the second leading cause of cancer morbidity and death in women, cervical cancer remains an important public health problem worldwide. Novel biomarkers with high sensitivity and specificity for the early detection and diagnosis of cervical cancer are urgently needed. Increasing evidence shows that long noncoding RNAs (lncRNAs) are differentially expressed in cancer tissues and may serve as diagnostic markers. In multiple tumor types, exosomes harboring lncRNAs are actively released from tumor cells. In this study, we investigate the potential association of exosomal lncRNA expression with cervical cancer. METHODS: Cervicovaginal lavage specimens were collected from patients with cervical cancer and cancer-free volunteers who are HPV-positive or HPV-negative. Exosomes in these specimens were isolated by ultracentrifugation and confirmed by transmission electron microscopy. The exosomal lncRNAs HOTAIR, MALAT1, and MEG3 were quantified by qRT-PCR. RESULTS: Expression of HOTAIR, MALAT1 and MEG3 was predominantly observed in cervical cancer-derived exosomes in cervicovaginal lavage samples. The expression levels of lncRNAs were significantly different in exosomes isolated from cervical cancer patients compared to normal controls. CONCLUSIONS: Our data suggest that lncRNAs in exosomes isolated from cervicovaginal lavage are differentially expressed in cervical cancer patients and cancer-free volunteers. Exosomal lncRNAs may have great potential to be used for the early detection and diagnosis of cervical cancer, and serve as convenient and noninvasive biomarkers.

Gout and Risk of Myocardial Infarction: A Systematic Review and Meta-Analysis of Cohort Studies.

INTRODUCTION: A high incidence of myocardial infarction among patients with gout has been suggested by several observational studies. We performed a meta-analysis to evaluate the association between gout and the risk of myocardial infarction. MATERIALS AND METHODS: The PubMed and Embase databases were searched from inception to October 2014 for cohort studies that evaluating the association between gout and the risk of myocardial infarction. Summary estimates were derived using a random-effects model and reported as relative risks (RRs) with 95% confidence intervals (CIs). RESULTS: Five studies involving 8,656,413 participants with a total of 1000 MI events were included. Overall, gout was associated with an increased risk of myocardial infarction (RR 1.45; 95% CI, 1.19-1.75; p<0.001), and the association referred to non-fatal myocardial infarction (RR 1.29; 95% CI, 1.19-1.39; p <0.001) but not fatal myocardial infarction (RR 1.11; 95% CI, 0.96-1.28; p = 0.174). The increased risk was observed in both women (RR 1.62; 95% CI, 1.18-2.21; p = 0.003) and men (RR 1.45; 95% CI, 1.21-1.74; p <0.001). Stratified analysis revealed a gradual increase in myocardial infarction risk with a younger age of gout onset (age 20-44 years old (RR 2.82; 95% CI, 1.38-5.79; p = 0.05); 45-69 years old (RR 1.85; 95% CI, 1.22-2.82; p = 0.04); ≥70 years old (RR 1.52; 95% CI, 1.22-1.88; p <0.001)). CONCLUSION: This meta-analysis suggests that patients with gout have an increased risk of myocardial infarction.

In vitro expression of Streptococcus pneumoniae ply gene in human monocytes and pneumocytes.

BACKGROUND: Streptococcus pneumoniae is one major cause of pneumonia in human and contains various virulence factors that contribute to pathogenesis of pneumococcal disease. This study investigated the role of pneumolysin, Ply, in facilitating S. pneumoniae invasion into the host blood stream. METHODS: S. pneumoniae strains were isolated from clinical blood and sputum samples and confirmed by PCR. Expression of ply gene was assessed by infecting human monocytes and pneumocytes. RESULTS: A total of 23 strains of S. pneumoniae isolated from blood (n = 11) and sputum (n = 12) along with S. pneumoniae ATCC49619 were used to infect human monocyte (THP-1) and Type II pneumocyte (A549) cell lines. All clinical strains of S. pneumoniae showed higher expression of ply mRNA than the American Type Culture Collection (ATCC) strain. Among the clinical strains, blood isolates showed higher expression of ply genes than sputum isolates, i.e., 2(1.5)- to 2(1.6)-folds in THP-1 and 2(0.4)- to 2(4.9)-folds in A549 cell lines. CONCLUSIONS: The data from the current study demonstrated that ply gene of blood- and sputum-derived S. pneumoniae is differentially expressed in two different cell lines. Under survival pressure, ply is highly expressed in these two cell lines for blood-derived S. pneumoniae, indicating that ply gene may facilitate S. pneumoniae invasion into the host blood system.

Effects of clinical isolates of Streptococcus pneumoniae on THP-1 human monocytic cells.

Twenty­three clinical Streptococcus pneumoniae (SP) strains were isolated from blood and sputum specimens from the Second Affiliated Hospital of Wenzhou Medical College in 2009. These strains and the ATCC 49619 standard strain were cultured and suspended in normal saline (at a turbidity of 1.0 McFarland). The production of interleukin (IL)­8, intracellular adhesion molecule­1 (ICAM­1) and IL­10 in THP­1 cells following stimulation with the SP suspension was analyzed by an enzyme-linked immunosorbent assay. The concentrations of IL­8, ICAM­1 and IL­10 from the THP­1 monocytes were greater than those of the blank control following stimulation with the SP suspension. No significant difference was identified in the levels of IL­8, ICAM­1 and IL­10 secretion between THP­1 monocytes stimulated by blood­borne SP (bb­SP) and sputum­borne SP (sb­SP).

Roles of virulence genes (PsaA and CpsA) on the invasion of Streptococcus pneumoniae into blood system.

BACKGROUND: Streptococcus pneumoniae (SP) is the major cause of childhood mortality worldwide, we need to understand virulence genes of SP so can better target the treatment.We investigated the expression of virulence genes PsaA and CpsA in different strains of SP interacting with monocyte cell line (THP-1) or pneumocyte cell line (A549) and the possible mechanism of SP invasion of the blood system. METHODS: A total of 23 strains of SP were collected from hospitalized patients (blood-derived and sputum-derived) in the Second Affiliated Hospital of Wenzhou Medical College. The strains and ATCC 49619 were cultured, and RNAs were extracted. THP-1 and A549 cells were stimulated by different SP and ATCC 49619 for 4 h and 8 h, respectively. Quantitative real-time PCR was used to analyze the mRNA expression of PsaA and CpsA. The data were analyzed by SPSS 17.0. RESULTS: The mRNA level of PsaA and CpsA were all significantly increased in clinical SP strains when compared to ATCC49619 after tedTHP-1 and A549 cells were stimulated. Clinical SPs showed higher virulence compared with ATCC49619. CONCLUSIONS: The expression of CpsA is the basis of the pathogenicity of SP. The expression of virulence gene PsaA may be helpful to the invasion of SP to the blood system.