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Objective To investigate the mechanism of pulmonary inflammation induced by influenza virus , and provide reference for the development of effective drugs for viral pneumonia .Methods An influenza PR8 infection mouse model was established .The levels of inflammatory cytokines and complement molecules were determined using RT -PCR and ELISA.The pathological changes were examined using biopsy .The complement inhibitor cobra venom factor ( CVF) was injected intraperitoneally at a dose of 50 μg/( kg· 24 h) , and then body mass .The survival rate and inflammatory factors were examined .Results Compared with the control group , the expressions of complement regulatory molecule Crry and CD59 were significantly decreased (P<0.01), while those of complement C9 and complement receptor C3aR and C5aR were significantly increased in the lungs of influenza model mice (P<0.01).Pro-inflammatory cytokines TNF-α, IL-6 and IFN-γwere highly expressed , but anti-inflammatory cytokine IL-2 was lowly expressed in serum .Treatment with CVF caused a sight body mass loss, a survival rate increase and a lung index decrease (P <0.05).Moreover, an IL-2 expression increase and a decrease of IL-6, TNF -αand INF-γexpression were observed in CVF treatment mice ( P< 0.05).Conclusion Inhibition of complement activation can increase the survival rate of mice with influenza pneumonia and decrease pulmonary indexes .thus delaying the pathogenesis of PR 8.
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Objective To investigate the status of food hygiene safety in troop catering units, analyze the major problems, and to improve the service system of food safety in troops.Methods Seventy troop catering units were investigated by means of cross-sectional questionnaire surveys, on-site inspections and rapid detection methods.Results Among the 70 troop catering units, 70.0%were self-managed,and 28.6%were run by civilians.From them, 64.3%of these units were centralized above the regimental level.Five main problems with food safety were found during food processing:uncomplete cleaning and disinfection of the tableware, irrational layout of processing rooms, co-contamination in the processing link, purchase and storage problems of raw materials, and sub-standard internal management of hygiene.44.3%of the catering units had inspection staff, 40.0% were equipped with inspection equipment, and 35.7% had food inspection rooms. Conclusion There are potential hazards to food safety in troop catering units.The implementation of hygienic regulations should be strengthened, and food safety related equipment improved.In addition, staff′s awareness of hygiene should be enhanced, internal supervision should be strengthened, and the mechanism of rewards and punishments should be established.
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Objective To develop a portbable incubator for on-site cultivation of microorganisms in foods and drinking water.Methods Cultivation temperature was set as required by the temperature for various microorganisms and PID was controlled via the single chip microcomputer and configuration screen .Then, the framework of the incubator was designed and assembled.Finally, the cultivation effect was tested .Results The incubator was compact and portable .The deviation of the temperature was in the range of 1℃.The hold time of self-contained power could exceed 8 h.In addition, the cultivation effect of our fabricated incubator was not significantly different from that of the commercial electro-heating standing-temperature cultivator used in laboratories .Conclusion The incubator is suitable for on-site detection of microorganisms in foods and drinking water , which is significant for spotting and removing the hidden dangers from microorganism contaminations in foods and drinking water in order to protect the health of soldiers .
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Objective To do screening acute lymphoblastic leukemia patients scFv antibody single chain variable region to cre-ate conditions for the expression and obtain further specificity of antibody fragments.Methods In this study,patients with newly diagnosed acute lymphoblastic leukemia serum as coating antigen using phage display technology,screening phage an-tibody specificity from the semi-synthetic human phage antibody libraries,the first to target the immune antigen-coated tab-let,phage library was added,so that with the target antigen-specific binding phage antibody was immobilized on plates immu-nization,could not be specifically bound phages were rinsed.The eluted specific binding phage,E.coli infection.Could get the specific antibody gene containing phagemid.Results After three “adsorption-elution-amplification”screening process,got stronger leukemia patient antigen-specific phage antibody variable region fragment and identification.Conclusion Got better strain affinity antibody fragments,to create the conditions for the next fragment expression,identification and clinical appli-cation.
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Rapid detection of pathogenic microorganisms is important to the prevention and control of diseases.Com-pared with traditional approaches, electrochemical DNA biosensors present great advantages in promising rapid, portable, sensitive and cost-saving detection of pathogens.In this review, the working principle of electrochemical DNA biosensors and the progress in detection of pathogens is introduced, the latest developments of DNA tetrahedron structure and new nano materials in electrochemical DNA biosensors are reviewed, and the challenges to and prospects of development in this field are also discussed.
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Objective To screen permethrin human single-chain variable region (scFv) antibody for aims of developing rapid detection kit. Methods Phage display technology was used in this study. Permethrin was solid phase coated on Nunc plate as antigen. Semi-synthetic single-chain variable region of human antibody library technology was applied, and single chain variable region was screened from phage antibody library after 3 rounds "adsorption - elution - amplification" of the selection process. 100 clones were random selected as resistance to permethrin clones , enzyme-linked immunosorbent assay (ELISA), crossreactivity and competitive inhibition experiments were used to validate permethrin binding activity with strong scFv clones from the selected phage antibody clones plasmid. The plasmid was digested with restriction enzyme Sfi Ⅰ / Not Ⅰ and subcloned into pCANTAB5E vector. After transformed into E. coli XL1BIue, the plasmid was identified by restriction enzyme analysis. Results After screening in 100 clones, 18 clones had high ELISA absorbance values ( A value) at 490nm wavelength ( A490nm), then bovine serum albumin (BSA) cross-reactions identified five weak cross-reaction. Combined with the triplicate ELISA and competitive inhibition experiment results, one positive clone was acquired at last. And this clone was subcloned into pCANTAB5E vector and transformed into competent cells XL1-Blue. Conclusion Plasmid fragment was consistent with the purpose, which provided the foundation for further study of its specific affinity.
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Objective To compare the safety and efficacy of varied treatments for cardioversion of paroxysmal atria] fibrillation (AF) in the aged patients and to explore choice of electrical cardioversion with direct current. Methods Clinical data of cardioversion with lanatoside (cedilandid) or propafenone, a sodium channel blocker prolongs refractoriness, for 57 aged patients with paroxysmal AF were summarized to observe their cardioversion and control of heart rate. And, synchronous electrical cardioversion will be offered to those with severe complications and ineffective with drug treatment within 24 h after the onset of AF. Results An emergency cardioversion ratio was 28.1 % with lanatoside within 24 h with a satisfactory control of ventricular rate, as compared with that of 62.2% with propafenone (P
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Objective To explore the effect of light chain gene library slauffling on the affinity of phage engineered antibody against HBsAg. Methods Human antibody light chain gene repertoire generated by RT-PCR from human peripheral blood lymphocyte, was inserted into the phagmid containing Fd gene to construct the phage antibody sublibrary, from which the light chain gene matching the heavy chain Fd gene was screened. Results After three rounds of selection by biopanning, eight clones with higher absorbency than that of original clone at 490nm in ELISA were obtained, indicating that the affinity of chain shuffled phage antibodies (phab) was improved (A_ 490 from 0.43?0.09 to 1.24?0.10). DNA sequencing showed three of the five V_L genes were ? type, and the other two were ? type. Conclusions The phab obtained possesses the specificity of anti-HBsAg property.
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Objective To screen and identify the human phage engineered antibodies against HBsAg, and to analyze their gene sequence. Methods The phage antibody library was constructed by phage surface display techniques, and then the antibody genes were isolated and amplified from human peripheral blood lymphocyte. The human phage engineered antibody against HBsAg was selected through bio-panning from the phage antibody library. The affinity and specificity of the phage antibody was identified by ELISA and inhibition ELISA assay. The genes of heavy chain and light chain of the phage antibody against HBsAg were analyzed by sequencing. Results 30 colonies were obtained after three rounds of bio-panning. One of them had the highest A490 (A490=1.47?0.08) with ELISA, and the inhibition rate was 76% with inhibition assay (A490=0.35?0.10), implying that the phage antibody against HBsAg was of high specificity. The findings of enzyme digestion demonstrated that the phage antibody included genes of heavy chain and light chain. Sequencing results indicated that the VH region of heavy chain belonged to VHI subgroup and the VL region of light chain belonged to V? Ⅰ and V? Ⅲ subgroup. Conclusions The specific human phage engineered antibody against HBsAg was selected successfully from the phage antibody library. These results suggest that screening and identification of human phage engineered antibody against HBsAg through the phage antibody library are technologically feasible. It lays a foundation for application of human engineered antibody against HBsAg to design new targeted therapy strategy for HBV.
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Objective To detect the single nucleotide polymorphism(SNP) of chemokine RANTES promoter of healthy and HIV 1 infected individuals of Han and Uiygur Chinese population, and to evaluate the correlation of their SNPs with HIV 1 infection. Methods Case control study was adopted ,Genotypies of RANTES promoter 403 and 28 from 863 samples were detected by DNA sequencing or by polymerase chain reaction restriction fragment length polymorphism. Results There were two SNPs and six genotypes in Chinese Han and Uiygur. 403 and 28 allelic frequencies were high, but there was no significant difference between the two healthy populations. Strong linkage disequilibrium was observed between the two SNPs. RANTES genotypes were AC/AC, AC/AG, AC/GC, AG/GC, GC/GC, and AG/AG. The haplotypes were GC 62 7% in both rases, AC 28 7% and 30 4%, AG 8 6% and 6 8% in Han and Uiygur, respectively. Compared with AC/AC, odd ratio (OR) of RANTES genotypes AC/AG, AC/GC, AG/GC, and GC/GC was associated with reduced susceptibility to HIV 1 infection. Conclusion Same high RANTES promoter mutation was found in Han and Uiygur populations. Compared with AC/AC, odd ratio (OR) of RANTES genotypes AC/AG, AC/GC, AG/GC 9.9%, and GC/GC might be associated with reduced susceptibility to HIV 1 infection. Further study of the implicated in needed