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Studies have shown that co-infection of influenza viruses with bacteria is an important cause of high mortality during the epidemic of influenza.There are at least 12 species of bacteria that have been reported to be able to co-infect with influenza.Among those species,co-infection with Staphylococcus aureus is not only the most common but also the most lethal.However,the pathogenesis of high mortality from co-infection with influenza virus/S.aureus remains elusive.In addition,co-infection of influenza virus/S.aureus can induce severe pneumonia.There is new evidence that influenza virus can reduce the host′s tolerance to pathogenic or inflammatory injury,and the two pathogens can also synergistically aggravate toxic effects on the host.Here,we review the mechanisms of severe mortality of influenza infection associated with S.aureus co-infections in order to contribute to prevention and control of influenza in the future.
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Drug control is still one of the main measures to control influenza. The current influenza prevention and treatment drugs mainly include M2 ion channel blockers and neuraminidase inhibitors. They have a certain therapeutic effect,but their resis?tance has also become increasingly prominent. In recent years,with the in-depth application of crystal lography,virology and other re?lated disciplines in the field of pharmacy,many new drugs have entered the(pre-)clinical test stage,and achieved good antiviral ef?fects. The most representatives include broad-spectrum anti-influenza virus hemagglutinin antibody and viral RNA polymerase complex small molecule inhibitors. Here,we introduce some new drugs against influenza so as to provide a reference for the prevention and con?trol of influenza epidemic.
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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 establish a quick electrochemical biosensor for the detection of nucleic acid of Ebola virus . Methods The DNA tetrahedral nanostructure was self-assembled on gold surface by strong Au-S chemical bonds , leaving the target probe at the top .A biotinylated-ssDNA was introduced as the detection probe by specific binding of the captured target sequence , before avidin-horseradish peroxidase ( HRP) was used as a signal amplifier to transduce amperometric sig-nal through interactions with TMB substrate .Results The results indicated that the nucleotide sequence of Ebola virus could be recognized and detected by the sensor .The linear range for the detection of target DNA was from 1.0 ×10 -9 to 5.0 ×10 -6 mol/L,and the detection limit was 5.2 ×10 -10 mol/L.Conclusion The fabricated sensor is demonstrated to be sensitive and specific for the detection of Ebola virus nucleotide .
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Rapid detection of infection pathogens is of great importance to the prevention and control of infectious diseases.Compared with traditional approaches,point-of-care testing (POCT) technologies promise great advantages in simple, rapid and portable detection of pathogens.In this review, the technologies, categories, developments and applications of POCT in detection of infectious pathogens are elaborated.Furthermore, the future developments of POCT detection of infectious pathogen are also discussed.This review focuses on loop-mediated isothermal amplification ( LAMP) technology, microfluidic chip and biosensor technology in the POCT detection of infectious pathogens while elaborating on the application of these new technologies associated with POCT detection.
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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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The immune system of bacteria against phage shares a lot of similarity with that of mammals, especially the adaptive immune system.The elements and components of the bacterial adaptive immune system———clustered regularly interspaced short palindromic repeats ( CRISPR ) and the mammalian adaptive immune system have a lot of parallel mechanisms.We could acquire new understanding about the immune function of CRISPR systems through that analogy.In recent years, researchers have found CRISPR-Cas system can play significant roles in regulating bacterial growth and metabolism.These researches have revealed new functions of CRISPR beyond immunity.The ability of CRISPR to affect gene expression has attracted increasing attention.Further studies are needed to shed light on the complicated functions of CRISPR.
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Objective To study the serotype , biochemical characteristics , virulence gene and multilocus sequence typ-ing(MLST) of S.flexneri 4c in Beijing, Shanghai and Shenyang .Methods Seventy-six strains of S.flexneri 4c isolated from stool samples which had been collected from above-mentioned cities of China were identified with Denka Seiken serum and MASF monoclonal serum .Biochemical characteristics of each strain were identified by API 20E test strip and PCR technology was used for detecting 12 pair virulence genes of S.flexneri.MLST was used to analyze the characteristics . Results The serum agglutination antigen structure of S.flexneri 4c was(Ⅳ:7,8).MASF:B+,Ⅳ:Ⅰ+,7 (8) +.S.flexneri 4c developed different results in biochemical reactions and carried different rates of virulence genes , respectively .The IND test positive rate was 17.11%; MEL weakly positive rate was 3.9%, and ARA test weakly positive rate was 22.37%. Virulence genes were carried at a rate of 89.47% -100%, MLST typing was ST245.Conclusion S.flexneri 4c with serum agglutination antigen structure (Ⅳ:7,8) is a new serotype of S.flexneri.The main biochemical reactions are glucose fermentation and mannitol decomposition .A variety of Shigella related virulence genes are carried .MLST generation is consistent,suggesting that the bacteria might have evolved from ST 270 cloning.
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Visit-to-visit variability [VVV] in blood pressure [BP] creates challenges to hypertension control and was independent associated with increased all-cause mortality in hypertensive patients. The major goal of the present study was to investigate the association of VVV in systolic [S]BP with progression of carotid atherosclerosis and endothelial dysfunction in on-treated hypertensive patients. Overall, 356 hypertensive patients were enrolled and completed the trial. Clinic BP was measured at base-line and at 3 monthly thereafter. Carotid artery ultrasound and endothelial function were evaluated at baseline and annually follow-up visit. VVV in BP was assessed by standard deviation [SD] and coefficient of variation [CV] of serial follow-up BP measurements. The patients were divided into low, middle, and high group by tertile of SD in SBP. Decrease percentage of maximum intima-media thickness [IMT] and stiffness index beta and increase percent-age of brachial flow-mediated dilation [FMD] and nitric oxide [NO] in lower groups were significant greater than in higher groups [P < 0.05]. Change percentage of stiffness index beta and endothelin-1 positively, and change percentage of FMD and NO negatively correlated with SD, CV, maximum, and delta of SBP [P < 0.05]. SD and CV of SBP were risk factors for change percentage of IMT, stiffness index beta, FMD, NO, and endothelin-1 independently of other influential factors, such as age, and mean SBP. Excessive VVV in SBP maybe increase carotid atherosclerosis and impair endothelial function in on-treated hypertensive patients. Reducing VVV in SBP is benefit for patients with hypertension management
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Humans , Male , Female , Systole , Carotid Artery Diseases , Endothelium , Hypertension , Disease ManagementABSTRACT
Objective To evaluate the effect of the urinary reservoir constructed with ileocecum-appendix in the elderly with bladder cancer. Methods From March 2002 to June 2008, 12 cases were treated using ileocecum-appendix as the reservoir after radical cystectomy. They all received the imaging urodynamics examination and were followed up for 1 year. Results The 11 of 12 patients had urinary continence completely. Only 1 case had incontinence and 3 cases had incontinentia urinae at night. Times of uresis were 8-10/day and 3-5/night within 3 months after surgery, and 4-6/day and 0-2/night 6 months after surgery. The urinary output was 150-350 ml/time. Urodynamics showed that mean urinary flow rate was 10.5 ml/s, mean initial bladder pressure was 27 cm H2O, the maximum filling pressure was 35 cm H2O. The average reservoir capacity was 152 ml and 420 ml, respectively. The out let pressure of posterior urethra was 52 cm H2O. The volume of residual urine was 0-65 ml. No evidence of ureteral reflux occurred, no hyperchloremic acidosis was observed. Conclusions Orthotopic bladder reconstruction is considered as an ideal form of urinary diversion characterized by low pressure, larger capacity and continence.
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Objective To study the efficacy of comprehensive treatment for type ⅢA prostatitis.Methods One hundred and eighty-four patients with type Ⅲ A prostatitis, recruited to this study, were comprehensively treated for 8 - 12 weeks by oral antibiotics and α-1 receptor antagonist,indometacin suppository applied into rectal, prostate massage and psychological counseling. The clinical effects of the treatment were evaluated according to the NIH chronic prostatitis symptom index (NIH-CPSI) and leukocyte counts in the expressed prostatic secretions ( EPS ). Results Before and after the treatment, the NIH-CPSI scores were 28. 6 ± 6. 5 and 12. 9 ± 3. 8 ( t = 28. 3, P ＜ 0. 05 ); the pain or discomfort scores were 14. 1 ± 3. 3 and 6. 4 ± 2.2( t = 26. 3, P ＜ 0. 05 ), the urinary symptoms scores were 5.6 ± 1.8 and 2. 1 ± 0. 9 ( t = 23.6, P ＜ 0. 05 ), the scores of life quality were 8.9 ± 3. 1 and 4. 4 ± 2.4 ( t = 15.6, P ＜ 0. 05 ), the leukocyte counts were ( 24. 5 ±4. 4)/HP and ( 6. 2 ± 2. 7 )/HP ( t = 48.1, P ＜ 0. 05 ) respectively, all comparisons showed significantly differences. Seventy-nine cases recovered completely, 57 cases recovered excellently, 36 cases recovered effectively and 12 cases did not recover, the overall effective rate was 93.5%. Conclusion Comprehensive treatment is an effective method for type Ⅲ A prostatitis.
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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 screen a human single-chain variable fragments(scFv)against antiGBM antibody.Methods Using phage display technique,the phage antibody library was panned by antiglomerular basement membrane(GBM)antibody which was coated in a micro-titer plate,one clone was found to have high affinity to anti-GBM antibody.The DNA sequence of the positive clone was determined.Results Along with the increase of rounds anti-GBM antibody specific phage antibody was highly enriched and screening efficiency was increased 137 folds than the firest round.ELISA and competition inhibition assay showed that the scFv had a specific combination character with anti-GBM antibody.DNA sequencing confirmed that the whole gene of scFv was 750 bp,and in accordance with humanized single-chain variable region antibody sequence structure.Conclusion The results suggested that the scFv fragment to anti-GBM antibody could be successfully selected by recombinant phage antibody technique,which will laid an experimental foundation for further research of the therapy of Goodpasture syndrome.
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The scientific research management is one of the critical factors to build up the innovative system of scientific research.There are two modes of scientific research management:self-organization and hetero-organization.The serf-organization management,which follows the rules of science development,is the precondition to advance the scientific research,it is also necessary to implement the hetero-organization in right time and right place.The management should conduct more investigation into the nature of scientific research,put the service on the important role and finally speed up the reforming of science research management mechanism.
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Objective To obtain Chinese hamster ovary (CHO) cell lines that stably express a targeting complement inhibitor CR2-CD59.Methods The recombinant plasmid PEE14.1-CR2-CD59 was constru-cted by cloning the DNA fragment CR2-CD59 into plasmid PEE14.1,and the obtained plasmid was transfected into CHO cells by FuGENE 6.The clones with stable high expression of target fragment were selected by methionine sulfoximine (MSX),the expression of CR2-CD59 was analyzed by ELISA,SDS-PAGE and Western blotting analysis.Results Several stable expression clones were obtained,and CR2-CD59 was highly expressed in the secret form in CHO cells.SDS-PAGE analysis showed that the molecular weight of the recombined protein CR2-CD59 was consistent with the predicted one.ELISA and Western blotting results revealed that the CR2-CD59 could react with both anti-human CR2 and anti-human CD59 polyclonal antibodies.Compared with serum-containing medium,the protein was highly expressed in serum-free medium (P
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Objective To investigate the serum coxsackie virus B(CVB) infection and nitric oxide (NO)level of the patients suffer from latent or chronic Keshan disease and their characteristics in the etiopathology of Keshan disease. Methods Sera were isolated from 30 patients with latent or chronic Keshan disease in Huangling county.Shaanxi Province, and the CVB-specific IgM antibody and NO were tested. Control groups were health subjects in Huangling county or Xi'an city, Shaanxi Province. Results The percentage of CVB-specific IgM positive in patients in Huangling county was significantly higher than that of both control groups in Huangling county and Xi'an city (P＜0. 05). The serum level of NO in patients was significantly higher than that of the control group in Huangling county (P＜0.05) ,however,compared with control group in Xi'an city, there was no difference (P＞0.05). In CVB-specific IgM positive patients,the serum level of NO was significantly higher than that of CVB-specific IgM negative group(P＜0.05).Conclusion CVB infection and serum NO level might be related to the etiopathology and the development of Keshan disease.
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Objective In order to investigate the relationship between erythrocyte immune function and seleni- um(Se) level. Method Red blood cell immune adherence(RCIA) function,serum RCIA regulatory factor, blood Se content and activities of glutathione peroxidase(GPX) of residents in Keshan disease(KD) endemic and non-endemic areas were comparatively studied. Forty-eight residents in KD endemic area aged 13～ 16 years were divided into 2 groups. The residents in the experimental group were orally given 200μg Se daily as Se yeast for 12 weeks, and their erythrocyte Se content and activity of glutathione peroxidase (GPX),RCIA function,serum RCIA regulatory function and circulating immune complexes(CIC) content were determined. ResultsThe results showed that the rosette for- mation rates of erythrocyte and blood Se levels of the residents in KD area were significantly lower and the rosette formation inhibitory rate of serum RCIA of the residents in KD area was significantly higher than those in the non-endemic area. Erythrocyte Se contents, GPX activities and rosette formation rates of erythrocyte were sig- nificantly increased and the rosette formation inhibitory rates of serum RICA were significantly decreased after sup- plementing Se,but the difference in the contents of serum CIC was not significant. ConclusionThe increase of ery- throcyte immune function by Se-supplement might be one of the effective mechanisms in the prevention of KD by Se- supplement.
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Abstract To evaluate the bioavailability of selenium (Se) in Se-yeast to residents with low-Se status, fifty-two youth in a Keshan disease area were randomly divided into three groups, and they were given orally 200 ?g Se daily as So-yeast or sodium selenite, or ordinary yeast for 12 weeks, respectively. Se contents and activities of glutathione peroxidase (GSHpx) in blood were measured at wk 4 and 8 of supplements and 8wk alter the supplements were discontinued. The results show that: 1. the retention of Se in either plasma or erythrocyte is sigificantly higher in Se-yeast than in sodiurn selenite; 2 the effect of Se in Se-yeast is superior to that of sodium selenite for maintaining GSHpx activities; and 3. the relative bioavailabilities of Se in Se-yeast are 556% and 178% when using erythrocyte and plasma Se contents as the response critria, as well as 158% and 116% when estimated by platelet and plasma GSHpx activities. The results indicate that the bioavailability of Se to the residents in a low-Se Keshan disease area is greater when supplemented Se-yeast than selenite.
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A three-phase depletion/repletion/depletion feeding study was designed to investigate the changes of Se levels and glutathione peroxidase (GSH-Px) activities in tissues and blood in rats fed for 6 weeks low-Se diet (6 ppb Se) from a Keshan disease area during the supplementations of Se as Ziyang high-Se wheat (1.175 ppm Se) or sodium selenite (dietary Se 219 and 223 ppb respectively) and after the supplements were discontinued, and to evaluate the relative bioavailability of Se in the wheat. The resalts showed that the average bioavailability of Se in high-Se wheat derived from the values at wk 2, 4 and 6 of supplement was close to that in selenite when plasma, erythrocyte, kidney, liver and cardiac Se contents were used as the response criteria, the relative bioavailabilities being 98%, 104%,100%,96% and 101% (sodium selenite = 100%) respectively. The bioavailability was lower for Se in high-Se wheat (70% or 90%) than for selenite when estimated by erythro-cyte or cardiac GSH-Px activities. However, the bioavailabilities of high-Se wheat Se in various tissues were not all the same at different stages of supplement. In addition, the effect of Se in high-Se wheat in maintaining either Se levels in heart, liver and erythrocyte or GSH-Px activity in heart was superior to that of selenite 3 weeks after the Se supplements were withdrawn.