The pandemic outbreak of influenza has been started from Mexico in 2009 to 70 countries during 2 months. On 11th of June , WHO announced influenza pandemic alert level rose to the highest level 6, which means the first influenza pandemic in 21st century is coming. Till 6th of July, 94 512 confirmed cases from more than 120 countries and areas were reported, including 429 cases were died. The genetic fragment of swine, poultry sources and human influenza viruses are contained in this strain, A/H1N1 influenza virus, of the pandemic. It is of great significance of studying the genetic reassortment, evolution and its biological characteristics of this virus strain to prevent and control the pandemic. At present, the genetic evolution of strain has been identified, and the potential biological characteristics have been analyzed by genetic traits, however, clinical manifestation should be further concerned, and the tendency of influenza pandemic and genetic changes need to be monitored closely. The complexity of influenza virus ecosystems, mutation of genome, and easy to preserve in "Nature Gene Pool" and reassortment, make the influenza pandemic inevitable. We should face the threat of influenza pandemic, enhance the surveillance of influenza virus in ecosystems, strengthen the epidemiological investigation, develop the vaccines and drugs, and establish an effective public health security system, in order to reduce the destruction of the influenza pandemic.

To study the effect of physiological conditions on spidroins, we analyzed NTR1SR2CT module secondary structure, aggregation and silk-formation influenced by different salts (in different concentration intervals). According to the full-length Araneus ventricosus MiSp sequence, NTR1SR2CT module was constructed and expressed in Escherichia coli BL21 (DE3), and the recombinant proteins were purified by denaturation method mediated by 8 mol/L urea. Random coil and helix are the main secondary structures of NTR1SR2CT and could be induced into beta-sheet by drying natively and lyophilization, where methanol can be used as a promoter. Furthermore, potassium and phosphate cations can cause significant NTR1SR2CT protein aggregation and silk-formation. The results could be a basis for the determination of silk-formation mechanism, and also useful for industrialized generation of high performance spider silk-like fibers.
Animals ; Fibroins ; chemistry ; Protein Structure, Secondary ; Salts ; chemistry ; Spiders

Objective To explore the possibility of early definitive operation for enteric fistulas. Methods In 37 selected enterocutaneous fistula patients, early definitive operation was performed during laparotomy for treating peritonitis within 10 days of fistula formation. Thorough irrigation of peritoneal cavity, effective sump drainage, fibrin glue sealant to reinforce anastomosis, appropriate nutritional support, and administration of growth hormone were key elements of perioperative management. Results Among 37 patients, 35 of them recovered uneventfully. Fistula recurred in 2 cases postoperatively; one fistula closed after conservative management, and another patient died of advanced gastric cancer 3 months postoperatively. The fistula operative closure rate was 94.5%. No operative death. Conclusion Advances in perioperative management can promote the success rate of early definitive operation for enteric fistulas. It may become a challenge to the present strategy of enteric fistula management.

Classic problem-based learning ( PBL ) was applied in a medical microbiology course.The results of questionnaire survey showed most of the students were satisfied with the whole learning program.They thought the case was appropriate,and the discussing could increase their understanding of the knowledge.Based on the problems faced during the application and the students' feedback,the duty of the tutors,summary of the learning topic,arrangement of the course,application of different teaching methods,and selection of the tutors were discussed in detail.

Objective To evaluate the application value of PCR-reverse dot blot hybridization in the identification of Candida and the detection of Candida albicans drug-resistant genes.Methods The vaginal secretion samples from 285 patients with candidal vaginitis and 50 healthy women were collected.The identification of Candida species and their drug susceptibility were detected by the bioMérieux Yeast identification cards and MIC method(Zhengzhou Antu kit),respectively.The identification of Candida species and the mutation of Candida albicans,drug-resistant genes were also detected by the Shenzheng Yaneng test kit(PCR-reverse dot blot hybridization).The drug-resistant genes were also identified by PCR and nucleic acid sequencing.Based on the culture identification,MIC method and nucleic acid sequencing as the contrast methods,the sensitivity,specificity and accuracy of PCR-reverse dot blot hybridization in the identification of Candida species and the mutation detection of Candida albicans drug-resistant genes were evaluated.Results Compared with the bioMérieux Yeast identification method,the sensitivity,specificity,positive predictive value,negative predictive value and total coincidence rate of PCR-reverse dot blot hybridization for detecting six kinds of Candida species,including Candida albicans,Candida glabrata,Candida tropicalis,Candida parapsilosis,Candida krusei and Candida guilliermondii,were above 95％,96％,96％,98％ and 97％,respectively.There was no significant difference in detecting six kinds of Candida species between the two methods (x2 =0.44,0,0,0,0 and 0,respectively,P ＞ 0.05),and there was good consistency between them (Kappa ＞ 0.9).Compared with the MIC method,the sensitivity,specificity,positive predictive value,negative predictive value and total coincidence rate of PCR-reverse dot blot hybridization for detecting the drug resistance of Candida albicans were 98％,88％,98％,88％ and 96％,respectively.There was no significant difference in detecting the drug resistance of Candida albicans between the two methods (x2 =0.17,P ＞ 0.05),and there was good consistency between them (Kappa ＞ 0.8).The results of PCR-reverse dot blot hybridization in detecting the mutation sites of six kinds of Candida albicans drug-resistant genes were 100％ of coincidence with that of the nucleic acid sequencing method.Conclusion The PCR-reverse dot blot hybridization has high consistency with the culture method and the nucleic acid sequencing method in the identification of Candida species and the mutation detection of Candida albicans drug-resistant genes,which is more early and rapid than the traditional detection methods,and may be applied to the auxiliary diagnosis of vulvovaginal candidiasis (VVC).

Objective To investigate the proof of fetal cells passing through the placental barrier into the maternal peripheral blood to provide laboratory data for the non invasive prenatal gene diagnosis of genetic diseases. Methods A total of 22 samples of placental tissues delivered(male fetus: 12, female fetus: 11) were divided into two groups for parallel section. HE staining was used to find the distribution of fetal cells in chorionic villi. In situ hybridization (ISH) technique with SRY DNA probes was used to identify the existence of fetal cells in placental villi, particularly in intervillous space. Results Light microscope examination revealed that there were fetal cells that passed through the capillary endothelium of villi and trophoblast basement membrane in the placental tissue sections of the 22 samples. ISH with SRY DNA probe also revealed that there were positive signals in the capillary of villi, at the edge of trophoblast basement membrane and in intervillous space in the placental tissue sections of the 12 placentas, but no signals were found in 10 female placentas. Conclusion This study demonstrates that the distribution of the fetal cells in the chorionic villi and intervillous space could be identified. The detection of fetal DNA in maternal circulation is one of the candidate approaches for non invasive prenatal gene diagnosis.

Objective To investigate whether S. pn can provoke filamentous actin (F-actin) rearrangements in vitro , which will further lead to S. pn invasion of A549 and the relationship between PLC signaling molecule and. the invasion events. Methods Labelled F-actin with FITC-phalloidin, we observed F-actin rearrangements by S. pn adhesion of type Ⅱ pneumocytes ( A549). S. pn invasion of A549 cells was determined by pretreating A549 cells with Cytochalasin D . To investigate whether F-actin rearrangements can be blocked by PLC inhibitor, A549 cells were pretreated with PLC inhibitors U73122. Results Intact S. pn can promote F-actin rearrangements. Cytochalasin D is able to prevent S. pn invasion of A549 cells. Inhibitors of PLC signal transduction molecules block F-actin rearrangements dose dependently. Conclusion S. pn can provoke F-actin rearrangements through PLC signaling pathways, which will further lead to S. pn invasion of A549 cells.

OBJECTIVE To determine the prevalence of post-operative infections in patients who underwent damage control laparotomy(DCL) with abdominal packing and to identify the risk factors,mortality and predominant pathogens.METHODS A retrospective study of postoperative infections and microbiology in patients who underwent abdominal packing as an adjunct of DCL to control coagulopathic hemorrhage over a 5 year period(Feb 2002-Feb 2007) were performed.RESULTS A total of 26 patients were studied.Pneumonia/lower respivatory tract infection was the prominant type of infection(57.7%),followed by bacteremia(50.0%),urinary tract infection(15.4%) and wound infection(15.4%).Of the 244 organisms isolated from various sites,the most frequently isolated bacteria were Pseudomonas aeruginosa(27.0%),Staphylococcus species(15.6%),Acinetobacter baumannii(13.9%),and Klebsiella species(11.1%).No statistical correlation was found between positive packs and postoperative infection(P=0.10) or death(P=1.00).Multivariate regression analysis revealed that pre-existing abdominal infection(OR=22.4,P=0.02) and increased number of surgical procedures(OR=3.69,P=0.05) were the independent risk factors for post-operative infections.CONCLUSIONS Patients who undergo DCL with packing have a high incidence of postoperative infections.Pathogens and distribution are same as acquired infections.Pre-existing abdominal infection and increased number of surgical procedures are the independent risk factors for postoperative infections in these patients.

Objective To study the pathogen spectra in patients with enterocutaneous fistula complicated with abdominal infection and their resistance to antibiotics. Methods The abdominal pus was collected from 226 patients with enterocutaneous fistula complicated with abdominal infection for bacterial culture and antibiotic susceptibility test. Results A total of 520 bacterial strains were harvested, including 333 strains of gram-negative bacteria, I 80 strains of gram-positive bacteria and 7 strains of fungi. The top 10 bacteria cultured were Escherichia coli (131 strains), Staphylococcus aureus (62 strains), Enterococcus (59 strains), Pseudomonas aeruginosa (50 strains), Klebsiella pneumoniae (23 strains), Acinetobacter baumannii (18 strains), Enterobacter cloacae (17 strains), Proteus mirabilis (15 strains), Morganella morganii (15 strains) and Enterococcus faecalis (12 strains). The extended spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae were 102 and 17 strains, respectively. Methicillin-resistant Staphylococcus aureus were 60 strains. Conclusions Gram-negative bacteria were the main pathogens in patients with enterocutaneous fistula complicated with abdominal infection. The positive rate of the extended spectrum beta-lactamase is high. Most of the Staphylococcus aureus were resistant to Methicillin.

Objective To investigate the clinical significance of the expression of XIAP mRNA and Survivin mRNA in non-small cell lung cancer and their relationship. Methods RT-PCR was used to evaluate the expression of XIAP mRNA and Survivin mRNA in 59 cases of NSCLC and corresponding normal tissues.Results There was a significant difference in XIAP mRNA expression in primary lung and corresponding normal tissues (61.0 % vs 30.5 %, P<0.05), whereas there were no significant correlation between the XIAP mRNA expression and gender, age, smoking history, histological subtype, T stage, lymph node metastatic status and TNM stage. There was a significant difference in Survivin mRNA expression in primary lung and corresponding normal tissues (81.4 % vs 23.7 %, P<0.05), whereas there were no significant correlation between the Survivin mRNA expression and gender, age, smoking history, histological subtype, T stage, lymph node metastatic status and TNM stage. Conclusion The significant difference of XIAP mRNA and Survivin mRNA expression between the tumor and corresponding normal tissues implies they might play important roles in the carcinogenesis and progress of NSCLC and might become marker for the diagnosis and target for treatment of NSCLC.