Epidemiological, molecular characterization and antibiotic resistance of Salmonella enterica serovars isolated from chicken farms in Egypt

Background Salmonella is one of major causes of foodborne outbreaks globally. This study was conducted to estimate the prevalence, typing and antibiotic susceptibilities of Salmonella enterica serovars isolated from 41 broiler chicken farms located in Kafr El-Sheikh Province in Northern Egypt during 2014–2015. The clinical signs and mortalities were observed. Results In total 615 clinical samples were collected from broiler flocks from different organs (liver, intestinal content and gall bladder). Salmonella infection was identified in 17 (41%) broiler chicken flocks and 67 Salmonella isolates were collected. Recovered isolates were serotyped as 58 (86.6%) S. enterica serovar Typhimurium, 6 (9%) S. enterica serovar Enteritidis and 3 (4.5%) were non- typable. The significant high mortality rate was observed only in 1-week-old chicks. sopE gene was detected in 92.5% of the isolates which indicating their ability to infect humans. All S. enterica serovar Enteritidis isolates were susceptible to all tested antimicrobials. The phenotypically resistant S. enterica serovar Typhimurium isolates against ampicillin, tetracycline, sulphamethoxazole and chloramphenicol were harbouring BlaTEM, (tetA and tetC), (sul1 and sul3) and (cat1 and floR), respectively. The sensitivity rate of S. enterica serovar Typhimurium to gentamycin, trimethoprim/sulphamethoxazole and streptomycin were 100, 94.8, 89.7%, respectively. The silent streptomycin antimicrobial cassettes were detected in all Salmonella serovars. A class one integron (dfrA12, orfF and aadA2) was identified in three of S. enterica serovar Typhimurium strains. Conclusions To the best of our knowledge, this study considered first report discussing the prevalence, genotyping, antibiotic susceptibility and public health significance of S. enterica serovars in broilers farms of different ages in Delta Egypt. Further studies are mandatory to verify the location of some resistance genes that are within or associated with the class one integron

The interaction of Escherichia coli O157 :H7 and Salmonella Typhimurium flagella with host cell membranes and cytoskeletal components

Bacterial flagella have many established roles beyond swimming motility. Despite clear evidence of flagella-dependent adherence, the specificity of the ligands and mechanisms of binding are still debated. In this study, the molecular basis of Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium flagella binding to epithelial cell cultures was investigated. Flagella interactions with host cell surfaces were intimate and crossed cellular boundaries as demarcated by actin and membrane labelling. Scanning electron microscopy revealed flagella disappearing into cellular surfaces and transmission electron microscopy of S. Typhiumurium indicated host membrane deformation and disruption in proximity to flagella. Motor mutants of E. coli O157:H7 and S. Typhimurium caused reduced haemolysis compared to wild-type, indicating that membrane disruption was in part due to flagella rotation. Flagella from E. coli O157 (H7), EPEC O127 (H6) and S. Typhimurium (P1 and P2 flagella) were shown to bind to purified intracellular components of the actin cytoskeleton and directly increase in vitro actin polymerization rates. We propose that flagella interactions with host cell membranes and cytoskeletal components may help prime intimate attachment and invasion for E. coli O157:H7 and S. Typhimurium, respectively

Type III Secretion-Dependent Sensitivity of Escherichia coli O157 to Specific Ketolides

A subset of Gram negative bacterial pathogens use a type 3 secretion system (T3SS) to open up a conduit into eukaryotic cells in order to inject effector proteins. These modulate pathways to enhance bacterial colonization. In this study we screened established bioactive compounds for any that could repress T3SS expression in enterohemorrhagic Escherichia coli (EHEC) O157. The ketolides, telithromycin and subsequently solithromycin both demonstrated repressive effects on expression of the bacterial T3SS at sub-minimum inhibitory (sub-MIC) concentrations, leading to significant reductions in bacterial binding and actin-rich pedestal formation on epithelial cells. Pre-incubation of epithelial cells with solithromycin resulted in significantly less attachment of E. coli O157. Moreover, bacteria expressing the T3SS were more susceptible to solithromycin and there was significant preferential killing of E. coli O157 when added to epithelial cells pre-exposed to the ketolide. This killing was dependent on expression of the T3SS. Taken together, this research indicates that the ketolide may traffic back into the bacteria via the T3SS from accumulated levels in epithelial cells. Considering that neither ketolide induces the SOS response, non-toxic members of this class of antibiotic, such as solithromycin, should be considered for future testing and trials in relation to EHEC infections. These antibiotics may also have broader significance for treating other pathogenic bacteria, including intracellular bacteria, that express a T3SS.Fil: Fernández Brando, Romina Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentina. University of Edinburgh; Reino UnidoFil: Yamaguchi, Nao. University of Edinburgh; Reino UnidoFil: Tahoun, Amin. University of Edinburgh; Reino Unido. Kafrelsheikh University; EgiptoFil: McAteer, Sean P.. University of Edinburgh; Reino UnidoFil: Gillespie, Trudi. University of Edinburgh; Reino UnidoFil: Wang, Dai. University of Edinburgh; Reino Unido. Xiamen University; ChinaFil: Argyle, Sally A.. University of Edinburgh; Reino UnidoFil: Palermo, Marina Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Gally, David L.. University of Edinburgh; Reino Unid

Development Automobile Engine Hood Latch

V diplomové práci se zabývá konstrukčním návrhem automobilového zámku, který má hlavní komponenty v „plastovém“ provedení (rohatka, západka, tělesa). Tyto plastové díly jsem vhodně navrhl a optimalizoval na požadované zatížení. Zároveň srovnávám plastový zámek a ocelový zámek přední kapoty, srovnávám jak cenu zámků, tak hmotnost a zatížení zámků. V krátkosti porovnávám automobilové zámky přední kapoty v současném automobilovém průmyslu. Také se zabývám etapou výroby prototypového vzorku v současnosti.The diploma thesis deals with the design of the car lock, which main components such as claw, pawl and housing are made of plastic. My main goal was to optimized these plastic parts for a certain amount of power. The following part shows a comparison of plastic lock and the steel lock of front bonnet. The following part shows a comparison of the plastic lock and the steel lock of the front bonnet. The comparison is made in terms of the price, weight and load of the locks. The diploma thesis also briefly deals with the comparison of car locks of car locks of front bonnets in the current automotive industry and the stage of prototype sample production nowadays.340 - Katedra výrobních strojů a konstruovánívelmi dobř

Cell Viability in Arthroscopic Versus Open Autologous Chondrocyte Implantation

Background: Autologous chondrocyte implantation (ACI) is an effective method of repair of articular cartilage defects. It is a 2-stage operation, with the second stage most commonly performed via mini-arthrotomy. Arthroscopic ACI is gaining popularity, as it is less invasive and may accelerate early rehabilitation. However, handling and manipulation of the implant have been shown to cause chondrocyte cell death. Purpose: To assess the number and viability of cells delivered via an open versus arthroscopic approach in ACI surgery. Study Design: Controlled laboratory study. Methods: Sixteen ACI surgeries were performed on young cadaveric knees by 2 experienced surgeons: 8 via mini-arthrotomy and 8 arthroscopically. Live and dead cells were stained and counted on implants after surgery. The cell number and viability were assessed using confocal laser scanning microscopy. Surgery was timed from knife to skin until the end of cycling the knee 10 times after implantation of the cell-membrane construct. Results: On receipt of cell membranes after transportation from the laboratory, ≥92% of the cells were viable. There were significantly more remaining cells (8.47E+07 arthroscopic vs 1.41E+08 open; P &lt; .001) and 16 times more viable cells (3.62% arthroscopic vs 37.34% open; P &lt; .001) on the implants when they were inserted via mini-open surgery compared with the arthroscopic technique. Open surgery was of a significantly shorter duration (6 vs 32 minutes; P &lt; .001). Conclusion: In this study, there were significantly more viable cells on the implant when ACI was performed via mini-arthrotomy compared with an arthroscopic technique. Clinical Relevance: The viability of cells delivered for ACI via an arthroscopic approach was 16 times less than via an open approach. The mini-arthrotomy approach is recommended until long-term clinical comparative data are available. </jats:sec

Excision and Episomal Replication of Cauliflower mosaic virus Integrated into a Plant Genome1[C][W][OA]

Transgenic Arabidopsis (Arabidopsis thaliana) plants containing a monomeric copy of the cauliflower mosaic virus (CaMV) genome exhibited the generation of infectious, episomally replicating virus. The circular viral genome had been split within the nonessential gene II for integration into the Arabidopsis genome by Agrobacterium tumefaciens-mediated transformation. Transgenic plants were assessed for episomal infections at flowering, seed set, and/or senescence. The infections were confirmed by western blot for the CaMV P6 and P4 proteins, electron microscopy for the presence of icosahedral virions, and through polymerase chain reaction across the recombination junction. By the end of the test period, a majority of the transgenic Arabidopsis plants had developed episomal infections. The episomal form of the virus was infectious to nontransgenic plants, indicating that no essential functions were lost after release from the Arabidopsis chromosome. An analysis of the viral genomes recovered from either transgenic Arabidopsis or nontransgenic turnip (Brassica rapa var rapa) revealed that the viruses contained deletions within gene II, and in some cases, the deletions extended to the beginning of gene III. In addition, many of the progeny viruses contained small regions of nonviral sequence derived from the flanking transformation vector. The nature of the nucleotide sequences at the recombination junctions in the circular progeny virus indicated that most were generated by nonhomologous recombination during the excision event. The release of the CaMV viral genomes from an integrated copy was not dependent upon the application of environmental stresses but occurred with greater frequency with either age or the late stages of plant maturation

Functional Analysis of a DNA-Shuffled Movement Protein Reveals That Microtubules Are Dispensable for the Cell-to-Cell Movement of Tobacco mosaic virus

Microtubules interact strongly with the viral movement protein (MP) of Tobacco mosaic virus (TMV) and are thought to transport the viral genome between plant cells. We describe a functionally enhanced DNA-shuffled movement protein (MP(R3)) that remained bound to the vertices of the cortical endoplasmic reticulum, showing limited affinity for microtubules. A single amino acid change was shown to confer the MP(R3) phenotype. Disruption of the microtubule cytoskeleton in situ with pharmacological agents, or by silencing of the α-tubulin gene, had no significant effect on the spread of TMV vectors expressing wild-type MP (MP(WT)) and did not prevent the accumulation of MP(WT) in plasmodesmata. Thus, cell-to-cell trafficking of TMV can occur independently of microtubules. The MP(R3) phenotype was reproduced when infection sites expressing MP(WT) were treated with a specific proteasome inhibitor, indicating that the degradation of MP(R3) is impaired. We suggest that the improved viral transport functions of MP(R3) arise from evasion of a host degradation pathway