OBJECTIVE To investigate pathogenic bacteria isolated from children with respiratory tract infection and bacterial resistance to commonly used antimicrcrobial agents. METHODS Routine methods were used to isolate and identify fastidious bacteria and Streptococcus from children throat swabs. The drug susceptibility tests were performed by Kirby-Bauer method. RESULTS One hundred and twenty four pathogenic bacteria were isolated from 300 samples. The isolation rate was 41.3% and the fastidious bacteria were 78 strains(62.9%). The resistant rate of Haemophilus influenzae to clarithromycimn, trimethoprim-sulfamethoxazoe(SXT) and ampicllin was 70.0%, 60.0%and 66.7%, respectively. The resistant rate of Streptococcus pneumoniae to tetracycline, clindamycin, SXT and azithromycin was 96.2% 92.3% 92.3% and 92.3%, respectively; the resistant rate of Streptococcus pyogenes to tetracycline, clidamycin and azithromyoin was 100.00%, 94.45% and 83.33%, respectively. CONCLUSIONS Fastidion bacteria and S. pyogenes are the main Pathogenic bacteria in children with respiratory tract infection. The antimicrobial agents should be chosen according to antimicrobial sasceptibility test results.

Objective To investigate the diagnostic value of serum brain natriuretic peptide(BNP)in chron-ic cor pulmonale of different period.Methods According to the inclusion criteria,we recruited 216 cases from heart and respiratory medicine(including outpatients and inpatients)of Qingyuan People 's Hosptial from April 2013 to December 2014.All the cases were divided into healthy control group(group A,n =48),cor pulmonale heart function compensatory period group(group B,n =43),cor pulmonale right heart failure group(group C,n =45),the simple left heart failure group(D group,n =40)and the whole heart failure group(group E,n =40).The serum BNP value,pul-monary function,echocardiography were detected.We compared the differences amomg them with correlation analysis, and drew the ROC curves to obtain the best cutoff point.Results The BNP value was higher in group C(495.44 ± 219.90)ng/L than group B[(182.44 ±69.71)ng/L,P <0.001],while the value was higher in group D(882.57 ± 288.56)ng/L and E(891.78 ±256.45)ng/L than group C(P <0.001).In cor pulmonale groups,BNP was positive-ly correlated with RV,RVOT,and PASP,negatively correlated with FEV1 ,and not correlated with LVEF %.In group D and E,BNP was negatively correlated with LVEF %.The best cutoff point of BNP was 285.3ng/L between cor pul-monale heart function compensatory period group(group B)and cor pulmonale right heart failure group(group C). The best cutoff point of BNP was 764.2ng/L between cor pulmonale right heart failure group(group C)and the whole heart failure group(group E).Conclusion There is certain correlation between serum BNP level and the progress of chronic cor pulmonale.Dynamic monitoring of serum BNP level in the judgement of treating cor pulmonale is of certain reference significance.

Objective To evaluate the effect of small interfering RNA targeting caspase-12 (caspase-12-siRNA) pretreatment on lung ischemia/reperfusion (I/R) injury in mice.Methods Forty male C57BL/6J mice,aged 6-8 weeks,weighing 16-24 g,were randomly allocated into 4 groups (n =10 each) using a random number table:sham operation group (group S),group I/R,negative control group (group NC) and caspase-12-siRNA pretreatment group (group siRNA).Lung I/R was induced by clamping the left pulmonary hilum for 30 min followed by 3 h reperfusion in anesthetized mice in IR,NC and siRNA groups.At 48 h before ischemia,negative control siRNA 20 μg and caspase-12-siRNA 20 μg were instilled intranasally in NC and siRNA groups,respectively,and the total volume was 50 μl.At 3 h of reperfusion,the animals were sacrificed and the left lung was removed for determination of wet/dry lung weight (W/D) ratio and lung water content in lung tissues and for microscopic examination.Pulmonary ultrastructure was examined with electron microscope.The quantitative evaluation index (QEI) for alveolar damage and apoptosis rate were calculated.Results Compared with group S,W/D ratio,lung water content,QEI for alveolar damage and apoptosis index were significantly increased in IR and NC groups,QEI for alveolar damage and apoptosis index were increased in group siRNA (P ＜ 0.05).Compared with IR and NC groups,W/D ratio,lung water content,QEI for alveolar damage and apoptosis index were significantly decreased (P ＜ 0.05),and the pathological changes of lungs were alleviated in group siRNA.There was no significant difference in the indices mentioned above between groups IR and NC (P ＞ 0.05).Conclusion Caspase-12-siRNA pretreatment can attenuate lung I/R injury in mice.