ObjectiveTo summarize the cause of laryngeal stridor in infants in order to make accurate diagnosis and treatment of the disease.MethodsWe reviewed medical records of 297 cases of patients less than 3 year of age with the presenting symptom of stridor who were initially evaluated in the outpatient setting of otorhinolaryngological department from Jan 2005 to Jan 2010.The causes of stridor were clarified by examinations of ultrafine electronic laryngoscope,throat three-dimensional CT,and bronchoscopy in all cases.Patients underwent history-taking,physical examination and flexible laryngoscopy,CT examination or bronchoscopy evaluation in the operating room.ResultsOf all 297 patients,199 cases ( 67.0％ ) were diagnosed as congenital airway abnomalities for cause of stridor,which included congenital laryngeal abnomalities in 169(84.9％,169/199) and congenital tracheal abnormalities in 30 cases( 15.1％,30/199).Another 98 cases (33.0％,98/297) were diagnosed as acquired disease for cause of stridor.The most congenital laryngeal anomaly was laryngomalacia ( 159,94.1％,159/169 ).The most congenital tracheal abnormalities was tracheomalacia ( 14,46.7％,14/30 ).Sixty-four cases ( 65.3％,64/98 ) were diagnosed as foreign body in airway and 26 cases (26.5％,26/98) were respiratory infection,which were the first and second most common causes of acquired disease for stuidor.ConclusionCongenital airway structural abnormalities as a major cause of infant laryngeal stridor,followed by acquired disorders,including airway foreign body and infection.

Objective To investigate the effects of inhibition of STAT5 gene expression by RNA interference technology on apoptosis of human hepatocellular carcinoma cell line SMMC-7721. Methods Three siRNA eukaryotic expression vectors against STAT5 were constructed and transfected with lipofectamineTM 2000 into SMMC-7721 cells. The changes in STAT5 expression were detected by semi-quantitative RT-PCR and Western blot. Cell apoptosis was assayed by flow cytometry (FCM). Results The sequence-specific siRNA could effectively and specifically inhibit STAT5 gene expression at both mRNA and protein levels. The inhibition rates of STAT5 mRNA expression were 70.43%, 43.02%, and 45.07%, respectively. The inhibition rates of STAT5 protein expression were 67.45%, 37.36%, and 41.86%, respectively. At 48 h after transfection, apoptosis rate was 25.61%. Conclusion siRNA against STAT5 can inhibit STAT5 gene expression in SMMC-7721 cells effectively and specifically and induce apoptosis of SMMC-7721 cells. siRNA targeting STAT5 has a great potential value in gene therapy of hepatocellular carcinoma.

We constructed prokaryotic recombinant expression vector of P61 gene from Nocardia brasiliensis,expressing P61 protein with biological activity in E.coli,and lay a foundation for further studies related to P61.P61 gene was synthesized and cloned into an expression vector pET-30a(+).The recombinant vector was transformed into Escherichia coli BL21 and induced with IPTG.The production was analyzed with Western blot and the catalase activity of P61 was tested with Catalase Assay Kit.The protein of P61was successfully expressed in E.coli with solubility and high catalase activity,and could be identified by anti-N.brasiliensis sera from mice.The prokaryotic expression plasmid of protein P61 was constructed successfully and can be expressed efficiently in E.coli BL21 cells with higher catalase.

Objective To investigate the distribution and drug resistance of pathogenic bacteria associated with ventilator associated infection in Intensive Care Unit (ICU) patients with severe tumor in Chengdu area. Methods 846 patients with severe and critical tumors who underwent mechanical ventilation in ICU from Jan-uary 2013 to December 2016 in Chengdu area were enrolled in the study.84 sputum specimens from patients with ventilator associated infection were collected ,bacteria were isolated and identified ,Gram-negative bacteria drug sensitivity test was carried out by GN201 method ,Gram-positive bacteria drug sensitivity test was carried out by GP method ,and drug sensitivity test was carried out by paper diffusion method.Results There were 80 strains of pathogenic bacteria in the sputum specimens from 84 patients with infection related infection ,inclu-ding 54 Gram-negative bacteria (67.50%) ,21 Gram-positive bacteria (26.25%) ,and 5 fungi (6.25%).The resistance rates of major Gram-negative bacteria to ceftazidime and cefepime were higher ,and the resistance rates of Pseudomonas aeruginosa to ceftazidime and cefepime were 94.74% and 89.47%,respectively ,the re-sistance rates of K lebsiella pneumoniae to ceftazidime and cefepime were 87.50% and 93.75%,respectively , and the resistance rates of Acinetobacter Bauman to ceftazidime and cefimidime were 100.00% and 83.33%, respectively ;the resistance rates of the main Gram-positive bacteria to penicillin and erythromycin were high-er ,and the resistance rates of Staphylococcus aureus to penicillin and erythromycin were 80.00% and 90.00%respectively ,the resistance rates of Staphylococcus hemolytic to penicillin and erythromycin were 87.50% and 75.00% respectively.Conclusion The pathogenic bacteria of ventilator associated infection in ICU patients with severe tumor in Chengdu area were mainly Gram-negative bacteria ,which should be paid attention to ,and effective monitoring and prevention measures should be taken for the relevant factors.

Objective To investigate the effects of high glucose and lysophosphatidylcholine (LPC) on the immune function of in vitro cultured macrophages during Nocardia farcinica infection. Meth-ods RAW264.7 macrophages were cultured in vitro under different conditions as follows: routine culture (control group),50 mmol/L glucose (high glucose group),10 mg/L LPC(LPC groupⅠ),25 mg/L LPC (LPC groupⅡ) and 50 mmol/L glucose+25 mg/L LPC(high glucose and LPC group). The activity of mac-rophages in each group was tested after 6,12,24 and 36 h of culture. After 24 h of culture, macrophages were collected from every group and co-cultured with Nocardia farcinica. Dynamic phagocytosis rates were detected at 1,2,3,4,5 and 6 h after co-culture. Toxic effects of Nocardia farcinica on macrophages and concentrations of IL-10 and TNF-α were measured at 1,3 and 6 h after co-culture. Results Macrophages in all four experimental groups showed decreased activity as compared with those in the control group (P<0.01). Phagocytosis of Nocardia farcinica by macrophages was also reduced by high glucose and LPC. Phagocytosis rates of high glucose group and LPC groupⅡ at 1 and 2 h,LPC groupⅠat 1,2 and 3 h,and high glucose and LPC group at 1,2,3 and 4 h after co-culture were significantly lower than that of the con-trol group (P<0.05 or P<0.01). Compared with the control group, significantly reduced toxic effects on macrophages caused by Nocardia farcinica was observed in the experimental groups (P<0.05 or P<0.01). Compared with the control group,LPC groupsⅠand Ⅱ and high glucose and LPC group had decreased se-cretion of IL-10 at 3 h,and high glucose group and LPC groupⅠhad decreased secretion of TNF-α at 1 h(P<0.05). Conclusion Culture macrophages under the conditions of high glucose and LPC would reduce their activity and impair their ability to phagocytose Nocardia farcinica. Moreover, high glucose and LPC might have impacts on the toxic effects of Nocardia farcinica on macrophages and the secretion of IL-10 and TNF-α.

Strain-resource engineering is often considered as an important infrastructure of microbiology related research and industry. The western developed countries took the lead in establishing the classical microbial resource utilization method, and continuously improved the preservation system, species annotation technology and global sharing mechanism, which realized the expansion and reserve of biological resources since end of the 19th century. The rich and diversified germplasm resources, standard strains and production strains not only have important economic values, but also maintain the advantages of scientific research, bioeconomy (such as antimicrobial agents, vaccines, detection reagent development and standard development, etc.) and national security. Although there has been a lot of progress in related research in recent years, compared with developed countries, there is still a big gap in related fields in China. The investment and top-level design in this area lag far behind the western developed countries, and it is not commensurate with the current level of economic and social development in my country. Drawing lessons from the practice of WFCC and WDCM (World Data Center for Microorganisms, Global microbial data Center, affiliated to WFCC), for the purpose of collecting new clinical species/strains, this paper puts forward some suggestions on the identification, preservation and upload system of isolates.

Objective To investigate the antimicrobial susceptibility of spectinomycin?minocycline?azithromycin and sparfloxacin to mycoplasma(Uu and Mh)and therapeutic effect of spectinomycin to my-coplasma infection in genitourinary tract.Methods①The susceptibility test:each of the4drugs was divided into two concentrations.One was at1?g/mL(sensitive concentration)and the other was at4?g/mL(resistant concentration).If mycoplasma does not grow in both concentrations,it means the drug tested is sensitive.If it grows in both concentrations,the drug tested is resistant.If mycoplasma grows in lower concentration and does not in higher concentration,it means moderate sensitive.②Treatment regimen:Spectinomycin was injected,2g/d IM,for7-10days as a course of treatmeant.Patients were followed-up7days later and2~4weeks after treatment.Results①Among1658specimens,519were found Uu positive,and61Mh positive.The resis-tance rates of Uu to4different drugs were:7.7%for minocycline,21.4%for sparfloxacin,13.9%for azithromycin and7.3%for spectinomycin.Whereas,those of Mh were:18.0%,45.9%,54.1%,and29.5%re-spectively.②The clinical effect of spectinomycin was:out of43treated patients,37(86.0%)cured,4(9.3%)markedly improved,2(4.7%)failed.Total effective rate was95.3%and so was the elimination rate of my-coplasma.Conclusion The resistant rate of mycoplasma to spectinomycin is lower than that to minocycline?azithromycin and sparfloxacin,and the former is widely used in the treatment of mycoplasma(especially Uu)infection,with a satisfactory clinical effect.