Journal of Medical Microbiology and Diagnosis最新文献

{"title":"Comparison of the Structure, Regulation and Functions between TypeThree and Type Six Secretion System in Gram-Negative Bacteria","authors":"Sara Badr, Yanqi Li, K. Duan","doi":"10.4172/2161-0703.1000243","DOIUrl":"https://doi.org/10.4172/2161-0703.1000243","url":null,"abstract":"Bacteria have evolved multiple protein secretion systems to survive and cope with surrounding environmental \u0000 stresses. So far, there are seven secretion systems (type I to type VII), which have been identified and demonstrated \u0000 the structural and molecular mechanisms. Among them, type three secretion system (T3SS), hallmark of acute \u0000 infection, is considered as the most complicated system and can translocate effector proteins directly into host cell through a needle-like apparatus. Type six secretion system (T6SS) targets both prokaryotic and eukaryotic cells \u0000 using a bacteriophage-like structure and plays a role in pathogenesis and bacterial competition. This review is based \u0000 on our understanding of comparison of the structure, regulation, function and application between T3SS and T6SS. \u0000 Understanding the structural and functional mechanisms, as well as the difference and relationship between these \u0000two secretion systems will help our understanding of bacterial pathogenesis and interspecies interaction.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127740003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights in Medical Microbiology and Diagnosis","authors":"J. Weltman","doi":"10.4172/2161-0703.1000E134","DOIUrl":"https://doi.org/10.4172/2161-0703.1000E134","url":null,"abstract":"Research article by Claudia Rizzo, Nadia Marascio, Emilia Zicca, Grazia Pavia, Angela Quirino, Angelo Giuseppe Lamberti, Maria Carla Liberto and Alfredo Focà. The gram-negative bacterium Acinetobacter baumannii (A. baumannii) is an increasingly significant cause of nosocomial infections. This study addresses the role of overexpression of the adeABC efflux pump as a cause of multidrug resistance (MDR), especially resistance to the antibiotic tigecycline, by A. baumannii isolated from such infections [5].","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122440699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathogenic Aerobic Bacterial Contaminants on Non-Critical HospitalSurfaces within Paediatric Ward of a Nigerian Hospital","authors":"S. Kh, Akanbi Ii Aa, Obasa To, R. Ra, Oshodi Aj, Kalgo Zm","doi":"10.4172/2161-0703.1000241","DOIUrl":"https://doi.org/10.4172/2161-0703.1000241","url":null,"abstract":"The study was a cross-sectional study of indoor hospital surfaces within paediatric wards to determine the pattern of pathogenic aerobic bacterial contaminants on non-critical surfaces within paediatric wards of UITH, Ilorin. A total of 201 surface swab samples were collected, using sterile ethylene oxide sterilized swab sticks premoistened with sterile normal saline, from selected non-critical surfaces and were aseptically cultured on media and incubated aerobically at 35°C to 37°C for 18 to 24 hours. Identification of bacterial isolates was carried out using standard microbiological procedure. Non-critical surfaces within paediatric wards: emergency paediatrics-unit 1 (EPU 1), emergency paediatric-unit 2 (EPU 2), paediatric medical-ward (PMW), paediatric surgical-ward (PSU) and neonatal intensive care unit (NICU). A prevalence of 67.7% was recorded for surface contamination; Staphylococcus aureus was the predominant isolate 39.4% and Pseudomonas aeruginosa 1.3% was the least contaminant isolated from this study. Wash sinks were the most commonly contaminated site amongst surfaces studied with a proportion of 123.5%, medical tables were the least contaminated with 33.33%. Among the wards sampled, EPU2 has the highest contamination level with 87.5% while NICU has the least contamination with 67.6%. This study showed that most of the sites sampled had bacterial contaminants indicating potential sources of cross contamination from surfaces to hands of healthcare workers, patients and vice-versa. It is pertinent to understand that non-critical hospital surfaces are important in the passive transmission of healthcare associated infectious pathogens. Thorough cleaning, disinfection of these surfaces and proper hand washing practices will break the chain of transmission.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122087899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Virulence Factors in Pseudomonas aeruginosa Strains Isolated from Cystic Fibrosis Patients","authors":"J. Jazayeri, K. Nguyen, D. Kotsanas, Fiona I. Schneiders, Chun-Hong Tan, M. Jazayeri, D. Armstrong","doi":"10.4172/2161-0703.1000242","DOIUrl":"https://doi.org/10.4172/2161-0703.1000242","url":null,"abstract":"Background: Pseudomonas aeruginosa, is a Gram-negative opportunistic bacterium which establishes itself in vulnerable patients, such as those with cystic fibrosis or hospitalized in intensive care units. \u0000Methods: Forty-five P. aeruginosa strains isolated from 26 cystic fibrosis patients were obtained. Both qualitative and quantitative assays were conducted to determine a number of virulence factors such as elastase, alkaline proteases and pyocyanin. Elastase gene expression profiling was conducted using RT-PCR. Spirometry was used to measure lung function and this was correlated to the severity of P. aeruginosa infection. Spirometry measurements i.e. forced expiratory volume (FEV) and forced vital capacity (FVC) were made to measure lung function and to see if there was any correlation with the production of virulence factors. \u0000Results: Virulence factors profiling revealed that about 30% of the isolates were of clinical significance having expressed a number of virulence factors, in particular elastase (lasB). \u0000Conclusion: Some strains of P. aeruginosa produce greater quantities of virulence factors and are more damaging to the lungs of patients with cystic fibrosis, although statistical analysis revealed no correlation between the virulence factors tested and the level of lung function. In addition, other factors such as biofilm formation may play a larger role for CF lung infections.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127496564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Detection of Panton-Valentine Leukocidin (PVL) Toxins in Clinical Isolates of Staphylococcus aureus from Maitama District Hospital, Abuja, Nigeria","authors":"Orji Ol, Olayinka Bo, B. Afolabi, P. EjikeugwuChika, E. Nwakaeze, Eze Cj, S. C. Eluu, C. Agbom","doi":"10.4172/2161-0703.1000240","DOIUrl":"https://doi.org/10.4172/2161-0703.1000240","url":null,"abstract":"Pathogenic Staphylococcus aureus is the most frequently isolated Gram positive bacterium from clinical specimens; and it is among the leading cause of infection in man. S. aureus has gained significant interest in recent years as an important nosocomial pathogen – owing to its multidrug resistant nature which is associated to several virulence factors of the organism including Panton-valentine leukocidin (PVL). PVL is part of the toxins produced by pathogenic S. aureus – which help the organism to exacerbate their pathogenicity/virulence in the phase of an infection. This study evaluated the prevalence of PVL-positive S. aureus from clinical specimens – owing to the dearth of information on this subject matter in Nigeria. Out of the 118 non-consecutive S. aureus isolates employed for this study, only 56 isolates were biochemically confirmed as pathogenic S. aureus. The antibiogram showed that the S. aureus isolates were most susceptible to gentamicin, vancomycin, ciprofloxacin, erythromycin and linezolid. However, they were highly resistant to the cephamycin, cefoxitin (82.1%). The S. aureus isolates also showed reduced susceptibility to tigecycline (71.4%), clindamycin (66.1%), chloramphenicol (48.2%), amoxicillin-clavulanic acid (53.6%) and sulphamethoxazole-trimethoprim (48.2%). The prevalence of PVL genes in this study was 10.7%. Only 6 isolates of S. aureus (10.7%) were confirmed by PCR to harbour the PVL genes; and these S. aureus isolates were from wound samples, abscess and urine samples. The occurrence of pathogenic S. aureus harbouring drug resistant genes such as PVL genes in the hospital environment pose serious health and therapeutic challenges especially in choosing antimicrobial therapy for treatment. S. aureus isolates with PVL genes could also disseminate with high propensity within the hospital environment; and this could result in the outbreak of nosocomial infections. Continues antibiotic stewardship in our hospitals will help in the control and prevention of the emergence and dissemination of drug-resistant microbes in both the community and hospital environment.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130335006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Virus-Free Synthesis of a Hepatitis C Virus P7 cDNA through a Three-Steps Polymerase Chain Reaction","authors":"E. Zicca, N. Marascio, Grazia Pavia, Francesco Bombardiere, S. D’Agostino, Fern, A. Fabiani, A. Bilotta, N. Perrotti, F. Trapasso, M. Liberto, A. Focà","doi":"10.4172/2161-0703.1000239","DOIUrl":"https://doi.org/10.4172/2161-0703.1000239","url":null,"abstract":"Hepatitis C virus (HCV) infection represents a great public healthcare challenge as it affects nearly 170 million individuals worldwide. Therefore, the deep investigation of the mechanisms involved in the pathogenesis of chronic hepatitis induced by HCV is a crucial step in the design of novel targeted therapies for the treatment of this condition. However, techniques of molecular biology to characterize HCV proteins can suffer of intrinsic limitations due to high mutation rates of the virus genome. \u0000In this study, we propose a novel strategy to synthesize a viral cDNA sequence corresponding to the p7 gene in HCV genome-free conditions. Our approach consists of a three-steps polymerase chain reactions (PCRs) by using a set of four large overlapping synthetic oligonucleotides aimed to separately amplify both 5’ and 3’ ends of the p7 gene; 5’ and 3’ products, overlapping themselves, were then used as a template in a third PCR amplification in order to get a full-length p7 cDNA. \u0000Our methodology represents an interesting proof-of-principle as it allows for the safe manipulation of short viral genes. Moreover, this new technique overcomes the elevated genetic variability of HCV genomes without affecting the antigenic characteristics of the putative viral protein.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124045120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autopsy: The Dying Diagnostic","authors":"A. Turnbull, M. Osborn","doi":"10.4172/2161-0703.1000238","DOIUrl":"https://doi.org/10.4172/2161-0703.1000238","url":null,"abstract":"Angus Turnbull1* and Michael Osborn2 1Imperial College School of Medicine, Sir Alexander Fleming Building, South Kensington Campus, London, UK 2Department of Cellular Pathology, Imperial College NHS Healthcare Trust, London, UK *Corresponding author: Angus Turnbull, Imperial College School of Medicine, Sir Alexander Fleming Building, South Kensington Campus, London, SW7 2AZ, UK, Tel: 44735650914; E-mail: ajt108@imperial.ac.uk","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116301448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efflux Pump AdeABC Assessment in Acinetobacter baumannii Strains Isolated in a Teaching Hospital","authors":"C. Rizzo, N. Marascio, E. Zicca, Grazia Pavia, A. Quirino, A. Lamberti, M. Liberto, A. Focà","doi":"10.4172/2161-0703.1000237","DOIUrl":"https://doi.org/10.4172/2161-0703.1000237","url":null,"abstract":"Over the past twenty years the worldwide clinically impact of Acinetobacter baumannii (A. baumannii) demonstrated its etiopathogenetic relevance. During a previously retrospective study in a teaching hospital, between January 2011 and February 2015, we observed increasingly infections caused by A. baumannii associated with antibiotic multi-resistance. Tigecycline, the first member of the glycylcycline class, is an effective option for the treatment of such infections even if, due to its increased clinical use, tigecycline resistant isolates have recently emerged. In A. baumannii several mechanisms are associated with a tigecycline decrease susceptibility, among these, expression efflux pump AdeABC and the presence of insertion sequence (IS) in the adeRS operon.About that, we decided to analyze adeB and adeS genes in 24 MDR A. baumannii clinical isolates, selected on the different tigecycline phenotype. The study of adeB and adeS genes was performed by an in-housepolymerase chain reaction (PCR) and by Sanger sequencing method. According to literature adeB and adeS genes were detected in all MDR A. baumannii isolates tested. Therefore our attention has focused on two resistant tigecycline clinical strains (ACI 2313 and ACI 1213), with a MIC value >8. In particular the ACI 2313 strains, showed the presence of an IS in the adeS gene. Then, adeS sequence analysis identified ISAba1 insertion. Moreover, adeB gene expression was evaluated by an in-house SYBR Green I-based real-time RT-PCR. We found an over expression of adeB gene in ACI 2313 strain, according to IS presence on adeS gene, while the lack of adeB overexpression in ACI 1213, still resistant to tigecycline, could be due to different resistance mechanisms.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132559299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computer-Assisted Vaccine Design by Analysis of Zika Virus E ProteinsObtained either from Humans or from Aedes Mosquitos","authors":"J. Weltman","doi":"10.4172/2161-0703.1000235","DOIUrl":"https://doi.org/10.4172/2161-0703.1000235","url":null,"abstract":"Information entropy (H) and predicted B cell epitope score (Bepipred) were determined for the envelope E protein of Zika viruses (ZIKV) isolated from infected humans and Aedes mosquitos with the aim of identifying E protein regions that may be useful as immunological targets of anti-ZIKV vaccines. Total H of mosquito origin E proteins was 4.2380 greater than that of E proteins of human origin, suggestive of constraints on ZIKV mutation in the human host. Seven invariant peptides (H=0.0) of length 10 amino acids, or greater, were identified. These peptide sequences where H=0.0 were screened for predicted epitopes. The seven invariant peptides were comprised of 93 amino acid residues, 31 of which demonstrated predicted B-cell epitopic activity. The predicted epitopic residues were distributed predominantly to 5 of the 7 invariant peptides. It is proposed that these 5 invariant (H=0) peptides in the E proteins of both human and Aedes mosquito ZIKV represent domains with constrained mutational/evolutionary potential and that epitopes predicted to reside in such invariant domains thus may be stable immunological targets for development of an anti-ZIKV vaccine.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122851264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In Vitro Evaluation of Antimicrobial Effect of Extracts of Medicinal PlantâÂÂsLeaves","authors":"Ale Zehra, S. Naqvi, S. Ali","doi":"10.4172/2161-0703.1000236","DOIUrl":"https://doi.org/10.4172/2161-0703.1000236","url":null,"abstract":"Abstract \u0000In ancient and modern epoch, aerial parts of herbal plants have been broadly used for the treatment of primary \u0000health care and variety of ailment across the world depends on geographical cultivation. Now a day’s researcher \u0000focuses their attention to explore the plants having broad spectrum therapeutic activity. On the basis of medicinal \u0000plant activity surveillance, the core goal step of current study is to evaluate the susceptible antimicrobial activity of \u0000crude 50% hydro alcoholic extract of leaves of different folk medicinal plant i.e Ocimum basilicum L., Cymbopogon \u0000citratus (DC.) Stapf., Olea europaea L., Eucalyptus camaldulensis Dehnh. against different clinical isolates \u0000(Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Pseudomonas aeruginosa, \u0000Staphylococcus aureus, Staphylococcu epidermidis, Salmonella typhi and Candida albican) of microbial disease \u0000so as to trip up on the other alternatives and overcome the upcoming era of increasing microbial resistance. These \u0000isolates were collected from different hospitals and pathological laboratories of Karachi, Pakistan. Extract were \u0000obtain by soaking the leaves in 50% methanol and then vacuum dried through Rotavapor while the antimicrobial \u0000activity were evaluated by well diffusion method. Overall outcome of current study endorse that among selected \u0000herbs, Olea europea possessed broad spectrum antimicrobial activity. Further investigation is needed to develop \u0000formulation from the same plant. It’s timely need to explore the antimicrobial activity of other herbs also.","PeriodicalId":269971,"journal":{"name":"Journal of Medical Microbiology and Diagnosis","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121652864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}