Patient-to-patient transmission of hepatitis C virus (HCV) during colonoscopy diagnosis

<p>Abstract</p> <p>Background</p> <p>No recognized risk factors can be identified in 10-40% of hepatitis C virus (HCV)-infected patients suggesting that the modes of transmission involved could be underestimated or unidentified. Invasive diagnostic procedures, such as endoscopy, have been considered as a potential HCV transmission route; although the actual extent of transmission in endoscopy procedures remains controversial. Most reported HCV outbreaks related to nosocomial acquisition have been attributed to unsafe injection practices and use of multi-dose vials. Only a few cases of likely patient-to-patient HCV transmission via a contaminated colonoscope have been reported to date. Nosocomial HCV infection may have important medical and legal implications and, therefore, possible transmission routes should be investigated. In this study, a case of nosocomial transmission of HCV from a common source to two patients who underwent colonoscopy in an endoscopy unit is reported.</p> <p>Results</p> <p>A retrospective epidemiological search after detection of index cases revealed several potentially infective procedures: sample blood collection, use of a peripheral catheter, anesthesia and colonoscopy procedures. The epidemiological investigation showed breaches in colonoscope reprocessing and deficiencies in the recording of valuable tracing data. Direct sequences from the NS5B region were obtained to determine the extent of the outbreak and cloned sequences from the E1-E2 region were used to establish the relationships among intrapatient viral populations. Phylogenetic analyses of individual sequences from viral populations infecting the three patients involved in the outbreak confirmed the patient pointed out by the epidemiological search as the source of the outbreak. Furthermore, the sequential order in which the patients underwent colonoscopy correlates with viral genetic variability estimates.</p> <p>Conclusions</p> <p>Patient-to-patient transmission of HCV could be demonstrated although the precise route of transmission remained unclear. Viral genetic variability is proposed as a useful tool for tracing HCV transmission, especially in recent transmissions.</p

CTX-M-15-Producing E. coli Isolates from Food Products in Germany Are Mainly Associated with an IncF-Type Plasmid and Belong to Two Predominant Clonal E. coli Lineages

Extended-spectrum beta-lactamases (ESBL) mediating resistance to 3rd generation cephalosporins are a major public health issue. As food may be a vehicle in the spread of ESLB-producing bacteria, a study on the occurrence of cephalosporin-resistantu Escherichia coli in food was initiated. A total of 404 ESBL-producing isolates were obtained from animal-derived food samples (e.g., poultry products, pork, beef and raw milk) between 2011 and 2013. As CTX-M-15 is the most abundant enzyme in ESBL-producing E. coli causing human infections, this study focusses on E. coli isolates from food samples harboring the blaCTX-M-15 gene. The blaCTX-M-15 gene was detected in 5.2% (n = 21) of all isolates. Molecular analyses revealed a phylogenetic group A ST167 clone that was repeatedly isolated from raw milk and beef samples over a period of 6 months. The analyses indicate that spread of CTX-M-15-producing E. coli in German food samples were associated with a multireplicon IncF (FIA FIB FII) plasmid and additional antimicrobial resistance genes such as aac(6)-Ib-cr, blaOXA−1, catB3, different tet-variants as well as a class 1 integron with an aadA5/dfrA17 gene cassette. In addition, four phylogenetic group A ST410 isolates were detected. Three of them carried a chromosomal copy of the blaCTX-M-15 gene and a single isolate with the gene on a 90 kb IncF plasmid. The blaCTX-M-15 gene was always associated with the ISEcp1 element. In conclusion, CTX-M-15-producing E. coli were detected in German food samples. Among isolates of different matrices, two prominent clonal lineages, namely A-ST167 and A-ST410, were identified. These lineages may be important for the foodborne dissemination of CTX-M-15-producing E. coli in Germany. Interestingly, these clonal lineages were reported to be widely distributed and especially prevalent in isolates from humans and livestock. Transmission of CTX-M-15-harboring isolates from food-producing animals to food appears probable, as isolates obtained from livestock and food samples within the same time period exhibit comparable characteristics as compared to isolates detected from human. However, the routes and direction of transmission need further investigation

Mutation of the 3-phosphoinositide-dependent protein kinase-1 (PDK1) substrate-docking site in the developing brain causes microcephaly with abnormal brain morphogenesis independently of Akt, leading to impaired cognition and disruptive behaviors

The phosphoinositide 3-kinase (PI 3-kinase)/Akt signaling pathway plays essential roles during neuronal development. The 3-phosphoinositide-dependent protein kinase 1 (PDK1) coordinates the PI 3-kinase signals by activating twenty three kinases of the AGC family including Akt. Phosphorylation of a conserved docking site in the substrate is a requisite for PDK1 to recognize, phosphorylate and activate most of these kinases, with the exception of Akt. We exploited this differential mechanism of regulation by generating neuronal-specific conditional knock-in mice expressing the mutant form of PDK1 L155E in which the substrate-docking site binding motif, termed the PIF-pocket, was disrupted. As a consequence, activation of all the PDK1 substrates tested excluding Akt was abolished. Mice exhibited microcephaly, altered cortical layering and reduced circuitry, leading to cognitive deficits and exacerbated disruptive behavior combined with diminished motivation. The abnormal patterning of the adult brain arise from the reduced ability of the embryonic neurons to polarize and extend their axons, therefore highlighting the essential roles that the PDK1 signaling beyond Akt plays in mediating the neuronal responses that are instructive for brain development

Experimental study of differentially rotating supersonic plasma flows produced by aluminium wire array Z-pinches

A novel approach to cylindrical wire array z-pinches has been developed in order to create a rotating plasma flow analogous to astrophysical accretion discs. The method involves subjecting the wire array to a cusp magnetic field (B_r) to create converging off axis ablation streams to form a rotating flow. The rotation is sustained by the ram pressure of the ablation streams in a quasi-equilibrium state for approximately 150 ns. This corresponds to one full rotation of the plasma about the axis. The rotating plasma is supersonic with Mach number ~2 and a radially constant rotation velocity between 60 and 75 km/s; the angular velocity therefore has an r^-1 dependence and the flow is differential. A Thomson scattering diagnostic is used to measure the electron and ion temperatures as Te ~30 eV and Ti >55 eV and the ionisation of the plasma (Z) between 6 and 8. These parameters are used to calculate the Reynolds number (10^5 to 10^6) and magnetic Reynolds numbers (20 to 100) which are large enough for viscous and resistive effects to be negligible on the large scale of the flow. These are of sufficient magnitude for the experiment to be scalable to astrophysical accretion discs. Further more the Reynolds number for the experiment is large enough for shear instabilities to manifest in the plasma. Some evidence for this can be seen in XUV images and Thomson spectra which indicate the development of perturbations and vorticity within the flow. Predictions for the growth rate of the Kelvin Helmholtz instability, 12 to 40 ns, agree reasonably well with the observed perturbation growth of ~30 ns. It is also possible that shear instabilities are driving hydrodynamic turbulence. Turbulent heating of the plasma could explain the approximately 500 eV increase in the ion temperature observed from some Thomson spectra. Further work is required however to prove the existence of shear flows and turbulence within the experiments.Open Acces

Microfiltración invitro de dos resinas condensables en restauraciones oclusales

Objetivo: Evaluar el grado de microfiltración in Vitro que se presenta en las restauraciones estéticas en premolares realizadas con dos tipos de resina, SureFil (Dentsply®) y P60 (3M®). Materiales y métodos: La muestra total del estudio se compuso de 30 premolares extraídos de pacientes por indicación ortodóntica, los cuales fueron dispuestos aleatoriamente en dos grupos cada uno conformado por 15 de estos dientes para ser obturados posteriormente con el tipo de resina correspondiente. Luego de ser obturados estuvieron sumergidos en una solución de azul de metileno al 2% durante 20 días para así después ser cortados en sentido coronal y poder analizar ambas mitades de cada diente con un microscopio electrónico especializado a una magnificación de 500X y finalmente poder comparar la cantidad de microfiltración que se presentaba. Resultados: Según los resultados arrojados por la prueba de medianas de Kruskal- Wallis analizada con el software Epinfo 6 versión 6.04 d – enero 2001 se observó que para ambas resinas se presentaba microfiltración aunque en cantidades individuales diferentes. Se vio mayor cantidad de microfiltración para las obturaciones realizadas con la resina P60 que las hechas con la resina surefil con un valor estadísticamente significativo (P= 0.012). Conclusiones: Según lo observado bajo microscopía electrónica, es mayor la microfiltración en la resina P60® que en la resina Surefil®[email protected]

mTAGs: taxonomic profiling using degenerate consensus reference sequences of ribosomal RNA genes

Profiling the taxonomic composition of microbial communities commonly involves the classification of ribosomal RNA gene fragments. As a trade-off to maintain high classification accuracy, existing tools are typically limited to the genus level. Here, we present mTAGs, a taxonomic profiling tool that implements the alignment of metagenomic sequencing reads to degenerate consensus reference sequences of small subunit ribosomal RNA genes. It uses DNA fragments, that is, paired-end sequencing reads, as count units and provides relative abundance profiles at multiple taxonomic ranks, including operational taxonomic units based on a 97% sequence identity cutoff. At the genus rank, mTAGs outperformed other tools across several metrics, such as the F1 score by >11% across data from different environments, and achieved competitive (F1 score) or better results (Bray–Curtis dissimilarity) at the sub-genus level.ISSN:1367-4803ISSN:1460-2059ISSN:1367-4803ISSN:1460-205

Brote de toxiinfección alimentaria por salmonella entérica en un establecimiento de restauración colectiva

Fundamento: Se describe un brote de toxiinfección alimentaria por Salmonella enteritidis ocurrido en dos salones de banquetes con ocho grupos de comensales afectados. El objeto de la investigación fue determinar el alimento vehículo de transmisión de la enfermedad. Métodos: Se analizaron los procesos de elaboración de los alimentos susceptibles de haber causado el brote. La asociación de los alimentos con la enfermedad se analizó mediante un diseño de casos y controles. Se calcularon las Odds Ratio ajustadas (ORa) y sus intervalos de confianza al 95% (IC95%) por regresión logística. Resultados: El número de comensales fue 1.771, distribuidos en 13 grupos durante tres días consecutivos. Se encuestó a 629 personas (36%). El número de casos probables fue de 250, 61 confirmados por salmonella enterica. El biscuit glasé (postre con huevo crudo sin tratamiento térmico) presentó la Odds Ratio ajustada más alta (ORa = 20,40; IC95%:7,52-55,30) y fue positivo a Salmonella enterica serotipo enteritidis. Conclusiones: Existe evidencia epidemiológica y de laboratorio de que el biscuit glacé fue el alimento contaminado que causó el brote. La investigación destacó como factores contribuyentes la utilización de huevo crudo, la producción en grandes cantidades y con antelación al consumo del alimento

Brote de toxiinfección alimentaria por salmonella entérica en un establecimiento de restauración colectiva

Fundamento: Se describe un brote de toxiinfección alimentaria por Salmonella enteritidis ocurrido en dos salones de banquetes con ocho grupos de comensales afectados. El objeto de la investigación fue determinar el alimento vehículo de transmisión de la enfermedad. Métodos: Se analizaron los procesos de elaboración de los alimentos susceptibles de haber causado el brote. La asociación de los alimentos con la enfermedad se analizó mediante un diseño de casos y controles. Se calcularon las Odds Ratio ajustadas (ORa) y sus intervalos de confianza al 95% (IC95%) por regresión logística. Resultados: El número de comensales fue 1.771, distribuidos en 13 grupos durante tres días consecutivos. Se encuestó a 629 personas (36%). El número de casos probables fue de 250, 61 confirmados por salmonella enterica. El biscuit glasé (postre con huevo crudo sin tratamiento térmico) presentó la Odds Ratio ajustada más alta (ORa = 20,40; IC95%:7,52-55,30) y fue positivo a Salmonella enterica serotipo enteritidis. Conclusiones: Existe evidencia epidemiológica y de laboratorio de que el biscuit glacé fue el alimento contaminado que causó el brote. La investigación destacó como factores contribuyentes la utilización de huevo crudo, la producción en grandes cantidades y con antelación al consumo del alimento

Brote de toxiinfección alimentaria por salmonella entérica en un establecimiento de restauración colectiva

Fundamento: Se describe un brote de toxiinfección alimentaria por Salmonella enteritidis ocurrido en dos salones de banquetes con ocho grupos de comensales afectados. El objeto de la investigación fue determinar el alimento vehículo de transmisión de la enfermedad. Métodos: Se analizaron los procesos de elaboración de los alimentos susceptibles de haber causado el brote. La asociación de los alimentos con la enfermedad se analizó mediante un diseño de casos y controles. Se calcularon las Odds Ratio ajustadas (ORa) y sus intervalos de confianza al 95% (IC95%) por regresión logística. Resultados: El número de comensales fue 1.771, distribuidos en 13 grupos durante tres días consecutivos. Se encuestó a 629 personas (36%). El número de casos probables fue de 250, 61 confirmados por salmonella enterica. El biscuit glasé (postre con huevo crudo sin tratamiento térmico) presentó la Odds Ratio ajustada más alta (ORa = 20,40; IC95%:7,52-55,30) y fue positivo a Salmonella enterica serotipo enteritidis. Conclusiones: Existe evidencia epidemiológica y de laboratorio de que el biscuit glacé fue el alimento contaminado que causó el brote. La investigación destacó como factores contribuyentes la utilización de huevo crudo, la producción en grandes cantidades y con antelación al consumo del alimento