Animal experiment on influenza virus infection carries certain biohazard risk, with a threat to the health of researchers and public health.The risk levels differ by influenza virus types and subtypes.This article combs the domestic and national laws and rules, and explores the biosafety management of animal study on influenza virus.

Objective To understand the distribution of pathogenic genes in uropathogenic Esche-richia coli (UPEC) from urinary specimen and to analyze the pathogenicity of UPEC and their mechanism of apoptosis to HeLa cells. Methods We have analyzed 6 pathogenic genes among the 28 strains of the clini-cally isolated E. coli from urinary tract infected patients. The 6 pathogenic genes were surveyed by using the PCR amplification of the target genes. The adhesion experiments and tryphan-blue staining was used to screen the phenotype of the pathogenic strains, while Annexin V/PI method was applied to study the strains to cause apoptosis of the HeLa cells, which was further confirmed with electronic microscopy. Results We have detected 6 strains that carried the usp gene. Phenotype screening identified two high virulent isolates (strain 6N and 27N) from the 6 strains. Strain 27N and 6N contained very similar virulence gene profile ex-cept that strain 27N did not contain usp gene. Both strains can destroy HeLa cell within 3 hours causing cell death. Results of apoptosis detected by flow cytometry revealed that strain 6N induced 20.75% of HeLa cells to an early stage apoptosis within 1.5 hours. On the other hand, strain 27N induced only 1.55% of HeLa cells to apeptosis. Conclusion High virulent UPEC strain carrying usp gene can induce HeLa cell rapid early apoptosis.

Objective To investigate the resistant mechanism of Streptococcus pyogenes to ciprofloxacin and its homology.Methods Forty-eight isolates of Streptococcus pyogenes were collected from patients diagnosed with scarflet fever in districts of Beijing in March,2012 and MIC to ciprofloxacin and other 7 common antibiotics in clinic were detected by using blood M-H agar dilution method.Thirteen isolates,which have MICs≥4 mg/L against ciprofloxacin,were detected for mutations of Fluoroquinolone resistance genes gyrA,gyrB,parC,parE.At the same time,4 isolates,with MIC ≤ 0.25 mg/L against ciprofloxacin,were used for comparison.Homology analysis of 17 isolates from different areas of Beijing was performed by using the method of pulsed field gel electrophoresis.Results Sensitive rates of Streptococcus pyogenes to levofloxacin,ampicillin and penicillin were all 100％.The resistance rates to tetracycline,erythromycin and clindamycin were 91.7％ (44/48),91.7％ (44/48) and 89.6％ (43/48),respectively.MIC50 of ciprofloxacin,levofloxacin and moxifloxacin was 2 mg/L,1 mg/L and ≤ 0.25 mg/L,respectively ; MIC90 was 4 mg/L,2 mg/L and 0.5 mg/L,respectively.Of the 48 isolates of Streptococcus pyogenes,12 isolates showed the MIC at 4 mg/L,while one isolate has a MIC against ciprofloxacin at 8 mg/L,which isolated from Chaoyang district.Analysis of sequence of chromosome mediated fluoroquinolone resistance genes in those 13 ciprofloxacin non-susceptible isolates exhibited that there were 12 isolates that harbored Ser79Phe/Tyr mutation and 10 isolates harbored Ala121Val in parC gene.It is shown that one isolate contained Ser79Phe mutation in parC gene in the occurring of Ser371Leu mutation in parE gene for the first time,but there was no marked increase in ciprofloxacin MIC (MIC =4 mg/L).There were no mutations in gyrA and gyrB genes.The PFGE results demonstrated that the 17 tested isolates could be divided into 7 clones.The clone A isolates from Chaoyang,Daxing,Fengtai,Shunyi and Shijingshan district have a MIC ≥ 4 mg/L against ciprofloxacin,which covered 69.2％ of all MIC ≥4 mg/L isolates.The clone C isolates from Huairou district were MIC ≥4 mg/L isolates.B,D,E,F and G clones isolates come from different districts.Conclusions The mutation of parC gene was the main reason that contribute to the slightly increase of ciprofloxacin MIC in Streptococcus pyogenes isolated from Beijing.The PFGE analysis showed that there was a small scale prevalence caused by the infection of Streptococcus pyogenes in some districts.

Objective To explore the related imaging factors about the change of systemic circulation time for aortic dissection (AD)patients.Methods Image data of 36 patients with AD and 30 patients in control group were analyzed retrospectively,the cor-relation analysis was made between the results of imaging measurement by using CT angiography (CTA)and the threshold time of the contrast agent in the left ventricular.3 6 patients with AD were divided into 2 groups (type A 1 7 cases and type B 1 9 cases)by using Stanford type.First,the threshold time in the left ventricular of the 3 groups were analyzed comparatively;next,the correla-tions between each CTA measured parameter and the threshold time in the left ventricle were analyzed.Results Threshold time in left ventricular of group Stanford A and group Stanford B were compared with the control group respectively,the overall mean difference was statistically significant (P <0.05).Between Stanford A and B,there was no significant difference (P>0.05).There was a significant correlation between threshold time in left ventricular and the ratio of false/true lumen (r=0.676,P<0.001).And the correlation was also found between threshold time and the maximum diameter of aorta or the diameter of intimal tear (r = 0.371 and 0.355,P> 0.05).Conclusion The threshold time of left ventricular for aortic dissection patients is significantly longer than the normal control group,and is significantly related with the ratio of false/true lumen.

Objective To evaluate the value of diffusion weighted imaging (DWI)in distinguishing the solid solitary pulmonary nodule (SPN).Methods 42 patients with SPN (malignant in 25 and benign in 1 7)who were confirmed by operation,biopsy or follow up after treatment underwent routine chest T1 WI,T2 WI and DWI.The b values were chosen as 300,500,800 and 1 000 s/mm2 ,and the corresponding apparent diffusion coefficient (ADC)values and the signal intensity (SI)were respectively measured.Results The ADC values and SI of benign and malignant SPNs were gradually reduced with increasing b value.The ADC value between benign and malignant SPNs was statistically significant with b value of 500 s/mm2 (P 500 =0.03 <0.05 ),meanwhile the SI was statistically significant with b values from 300 to 1000 s/mm2 (P 300 <0.001,P 500 =0.03 <0.05,P 800 =0.01 <0.05, P 1 000 =0.02<0.05).Conclusion Both SI and ADC value of DWI play important role in distinguishing benign and malignant SPNs, and the diagnostic efficiency of SI is superior to ADC value.

Objective To explore the relationship between polymorphisms of XbaI and MspI loci of apolipoprotein B (ApoB) gene and -75 bp,+83 bp loci of apolipoprotein AI (ApoAI) gene and coronary heart disease (CHD) in Kazaks of Xinjiang Uyghur Autonomous Region,China.Methods These loci were analyzed by PCR-restriction fragment length polymorphism (PCR-PFLP).Two hundred and five patients with CHD and two hundred and thirty six controls were involved.Results There were significant distinctions among low-density lipoprotein cholesterol (LDL-C),triglyceride (TG) and the ApoAI/ApoB ratio between the two groups,but no significant distinction among the polymorphism frequencies of the four sites between the two groups.The polymorphism coalition frequency of X-/Ms++/M1+-/M2++ (named Coalition 11) was significantly higher in CHD compared to the control group (14.6％ vs.7.2％,P ＜ 0.05).The level of total cholesterol (TC) in Coalition 1 1 was significantly higher and the level of the ApoAI/ApoB ratio in Coalition 11 was significantly lower than Coalition 1～10 in CHD patients.The level of the ApoAI/ApoB ratio of Coalition 11 was significantly lower than the Coalition 1～10 in control group.The levels of ApoAI/ApoB ratio of Coalition 3 were significantly higher compared to Coalition 11 in the two groups,respectively.The level of LDL-C of Coalition 3 was significantly lower than in the Coalition 11 in control group.The level of TC of Coalition 5 was significantly higher than Coalition 3 in the CHD group.The level of the ApoAI/ApoB ratio of Coalition 5 was significantly lower than in Coalition 3 or Coalition 1～10 of the two groups,respectively.The level of LDL-C of Coalition 5 was significantly higher than in Coalition 3 in control group.The ratio of ApoAI/ApoB was negatively related to TC,LDL-C and was positively related to HDL-C,both in CHD and control groups.Conclusion Coalition 11 of the 4 loci polymorphisms of the ApoB and ApoAI genes was correlated with CHD in Kazaks,and perhaps the ratio of ApoAI/ApoB was the most diagnostic parameter related with CHD among all lipid parameters.CHD may also be associated with Coalition 5,and,perhaps,Coalition 3 may have been confirmed as a protection factor against CHD,if more samples were enrolled.

Objective To investigate the molecular types of carbapenem-non-susceptible Esche-richia coli ( E.coli) isolates and their mechanism of carbapenem resistance .Methods Twenty-two carbap-enem-non-susceptible E.coli strains were isolated from 3 hospitals in Hangzhou from 2007 to 2011.The mini-mum inhibitory concentrations ( MICs) of antimicrobials to those isolates were determined by agar dilution method and E-test.The molecular mechanisms of carbapenem resistance of E.coli isolates were analyzed by conjugation experiment,PCR and DNA sequencing.Pulsed-field gel electrophoresis (PFGE),multilocus se-quence typing ( MLST ) , and phylogenetic typing were performed to analyze the molecular epidemiology of those isolates.Results The MICs of imipenem and meropenem to 22 E.coli isolates were ranged from 1 μg/ml to 16 μg/ml,and the MICs of ertapenem were 2 μg/ml to 64 μg/ml.All E.coli isolates produced the KPC-2 carbapenemase and various β-lactamases , and some of them also produced plasmid-mediated AmpC enzymes.Carbapenem resistance was transferred by conjugation and transformation from 22 E.coli iso-lates to E.coli EC600 strains.The E.coli transconjugants or transformants acquired the blaKPC-2 gene and showed similar antibiotic susceptibility patterns in comparison with donor strains .Only a few isolates were in-distinguishable or closely related as indicated by PFGE .Four sequence types including ST131 (9 isolates), ST648 (5 isolates),ST38 (2 isolates) and ST405 (2 isolates) were identified by MLST.Phylogenetic analy-sis indicated that 9 ST131 isolates belonged to phylogenetic group B 2 and the other isolates belonged to group D (11 isolates),group B1 (1 isolate) and group A (1 isolate),respectively.Conclusion The sequence type of prevalent E.coli isolates producing KPC-2 from Hangzhou was ST131,which is an international epi-demic,multidrug-resistant clone,followed by ST648.

To design a mobile device for infants appeasing in order to improve CT of the infant. The device was composed of the components of broadcasting, supporting and monitoring. The broadcasting component consist-ed of a high-definition 14-inch monitor and a DVD player, the supporting component was made up of the bar connector, base supporter and fastening bolt, and the monitoring component included a camera and a monitor. The head CT exami-nation results with the device were compared with those without the device. The device could significant improve the head CT examination of the infants. The device can enhance infants CT examination by appeasing them, and thus is worthy popularizing practically.

Objective To assess the CT characteristics of thoracoabdominal localized Castleman disease (LCD) in 55 cases and correlate with histopathologic features. Methods Fifty-five patients with LCD proved histopathologically in thorax ( n = 25 ) and abdomen ( n = 30 ) were collected during past 20 years. The unenhanced and contrast-enhanced CT were performed in all patients. Two radiologists reviewed CT images and the CT findings were analyzed simultaneously. Results In 54 patients with hyaline-vascular type ( n = 50 ) and mixed type ( n = 4 ) localized CD, the lesion typically presented as solitary mass (90. 7% , 49 cases), with irregular or lobular or infiltrative margin ( 83.3% , 45 cases),central calcification (38. 9%, 21 cases), marked enhancement (100% , 54 cases), focal non-necrosis low attenuation areas (72. 2%, 39 cases), lymphadenopathy (70.4%, 38 cases) and dilated feeding vessels adjacent to the mass (96.3%, 52 cases). One lesion with plasma cell type localized CD presented as a mass with irregular margin, mild enhancement and central necrosis. Four morphologic patterns wereclassified on CT, including solitary mass with well-circumscribed margin (n =4), irregular or lobular margin ( n = 30), infiltrative or halo-like margin ( n = 16 ), and multiple coalescent maasses ( n = 5 ). Conclusion CT features of thoracoabdominal localized CD are closely related to the location and pathological type. LCD with hyaline-vascular and mixed type has typical CT characteristics, while LCD with plasma cell type has no typical CT findings.

Objective To investigate the effect and mechanism of programmed cell death 4 ( PDCD4 ) on radiosensitivity of pancreatic cancer cells. Methods Pancreatic cancer tissues and corresponding adjacent tissues were collected, the expression level of PDCD4 was detected by RT-PCR and Western blot. Human pancreatic cancer cells Sw1990 were transfected with PDCD4 overexpression vector ( group pIRES2-PDCD4 ) , empty vector ( pIRES2 group ) , and treated with transfection reagent, respectively. The expression level of PDCD4 was detected by RT-PCR and Western blot. After radiation treatment, cell apoptosis was detected by flow cytometry, cell survival was detected by clone assay, and the expression levels ofβ-catenin, c-myc and Cleaved Caspase-3 were detected by Western blot. Results The expression of PDCD4 mRNA and protein in pancreatic cancer tissues was significantly lower than that in adjacent tissues (t=4. 869, 9. 208, P<0. 05). The expression of PDCD4 mRNA and protein in pIRES2-PDCD4 group was significantly lower than that in the non-transfection group ( t =9. 074, 18. 927, P <0. 05). After radiation, the apoptosis rate and Cleaved Caspase-3 level in the pIRES2-PDCD4 group were significantly higher than those in the non-transfection group (t =3. 670, 4. 086, P <0. 05), while the expression levels of β-catenin and c-myc in the cells were significantly lower than those in the non-transfection group (t =9. 242, 17. 644, P <0. 05). The radiosensitivity of pIRES2-PDCD4 group was higher than that of non-transfection group, and the sensitization ratio was 1. 843. Conclusions PDCD4 can increase radiosensitivity and promote apoptosis of pancreatic cancer cells, to which the Wnt signaling pathway may be related.