549 research outputs found

    The Type VI Secretion System Plays a Role in Type 1 Fimbria Expression and Pathogenesis of an Avian Pathogenic Escherichia coli Strain

    Get PDF
    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Avian pathogenic Escherichia coli (APEC) strains frequently cause extraintestinal infections and are responsible for significant economic losses in the poultry industry worldwide. APEC isolates are closely related to human extraintestinal pathogenic E. coli (ExPEC) strains and may also act as pathogens for humans. Known APEC virulence factors include adhesins such as type 1 fimbriae and curli, iron acquisition systems, and cytotoxins. Here we show that APEC strain SEPT362, isolated from a septicemic hen, expresses a type VI secretion system (T6SS); causes cytoskeleton rearrangements; and invades epithelial cells, replicates within macrophages, and causes lethal disease in chicks. To assess the contribution of the T6SS to SEPT362 pathogenesis, we generated two mutants, hcp (which encodes a protein suggested to be both secreted and a structural component of the T6SS) and clpV (encoding the T6SS ATPase). Both mutants showed decreased adherence and actin rearrangement on epithelial cells. However, only the hcp mutant presented a mild decrease in its ability to invade epithelial cells, and none of these mutants were defective for intramacrophage replication. Transcriptome studies showed that the level of expression of type 1 fimbriae was decreased in these mutants, which may account for the diminished adhesion and invasion of epithelial cells. The T6SS seems to be important for the disease process, given that both mutants were attenuated for infection in chicks. These results suggest that the T6SS influences the expression of type 1 fimbriae and contributes to APEC pathogenesis.781249904998NIH [AI053067]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)NIH [AI053067]FAPESP [2008/56739-6, 07/50432-3]CAPES [4062086

    Measuring a Safety Culture: Critical Pathway or Academic Activity?

    Get PDF
    he Institute of Medicine (IOM) identified six core needs in a health care system, the first of which was safety. 1 Furthermore, several IOM committees and others have identified the creation of a “culture of safety ” as the key institutional requirement to achieve safe medical care. 1–3 In this issue of the journal, Modak et al. 4 present an instrument that may help measure the extent to which a patient safety culture exists in an ambulatory setting. While these authors and others have done considerable work on defining and measuring a culture of safety in the hospital setting, 5,6 few have tackled the difficult task of measuring a safety culture in the ambulatory arena within the US health care system. Even in the hospital setting, where there has been more effort, the development of a culture of safety within all US hospitals has been spotty and, for some safety advocates, too slow. 7 There are many potential reasons for the poor progress in developing a culture of safety: confusion about the difference between safety and quality, concerns that increasing safety will further erode profits, or perhaps simply a lack of attention by institutional leaders. Whatever the reasons for the slow pace of transformation across the nation’s 5,000-plus hospitals, it is likely that this transformation will be even more difficult to achieve in the much larger and more diverse ambulatory setting. Thus, it is important to define and measure an ambulatory culture of safety. It is also difficult, perhaps impossible, to change beliefs, attitudes, knowledge, or actions (all components of a “culture”) without some form of feedback. Therefore, a necessary step in creating a culture of safety is to develop tools to measure the components of that culture. For those individuals and institutions that wish to truly improve the safety of the care they deliver, the creation and testing of tools such as the Safety Attitudes Questionnaire-Ambulatory (SAQ-A) version is critical. Beliefs, attitudes, and knowledge do not always lend themselves to clear-cut end points. Thus, we can expect to see more than one safety culture measuremen

    Paramedic clinical decision making during high acuity emergency calls: design and methodology of a Delphi study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The scope of practice of paramedics in Canada has steadily evolved to include increasingly complex interventions in the prehospital setting, which likely have repercussions on clinical outcome and patient safety. Clinical decision making has been evaluated in several health professions, but there is a paucity of work in this area on paramedics. This study will utilize the Delphi technique to establish consensus on the most important instances of paramedic clinical decision making during high acuity emergency calls, as they relate to clinical outcome and patient safety.</p> <p>Methods and design</p> <p>Participants in this multi-round survey study will be paramedic leaders and emergency medical services medical directors/physicians from across Canada. In the first round, participants will identify instances of clinical decision making they feel are important for patient outcome and safety. On the second round, the panel will rank each instance of clinical decision making in terms of its importance. On the third and potentially fourth round, participants will have the opportunity to revise the ranking they assigned to each instance of clinical decision making. Consensus will be considered achieved for the most important instances if 80% of the panel ranks it as important or extremely important. The most important instances of clinical decision making will be plotted on a process analysis map.</p> <p>Discussion</p> <p>The process analysis map that results from this Delphi study will enable the gaps in research, knowledge and practice to be identified.</p

    Some Like It Fat: Comparative Ultrastructure of the Embryo in Two Demosponges of the Genus Mycale (Order Poecilosclerida) from Antarctica and the Caribbean

    Get PDF
    0000-0002-7993-1523© 2015 Riesgo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License [4.0], which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

    Anatomical, Clinical and Electrical Observations in Piriformis Syndrome

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>We provided clinical and electrical descriptions of the piriformis syndrome, contributing to better understanding of the pathogenesis and further diagnostic criteria.</p> <p>Methods</p> <p>Between 3550 patients complaining of sciatica, we concluded 26 cases of piriformis syndrome, 15 females, 11 males, mean age 35.37 year-old. We operated 9 patients, 2 to 19 years after the onset of symptoms, 5 had piriformis steroids injection. A dorsolumbar MRI were performed in all cases and a pelvic MRI in 7 patients. The electro-diagnostic test was performed in 13 cases, between them the H reflex of the peroneal nerve was tested 7 times.</p> <p>Results</p> <p>After a followup 1 to 11 years, for the 17 non operated patients, 3 patients responded to conservative treatment. 6 of the operated had an excellent result, 2 residual minor pain and one failed. 3 new anatomical observations were described with atypical compression of the sciatic nerve by the piriformis muscle.</p> <p>Conclusion</p> <p>While the H reflex test of the tibial nerve did not give common satisfaction in the literature for diagnosis, the H reflex of the peroneal nerve should be given more importance, because it demonstrated in our study more specific sign, with six clinical criteria it contributed to improve the method of diagnosis. The cause of this particular syndrome does not only depend on the relation sciatic nerve-piriformis muscle, but the environmental conditions should be considered with the series of the anatomical anomalies to explain the real cause of this pain.</p

    Effort angina in a patient with advanced coronary artery disease. Role played by coronary angiography, Ivus and cardiac CT: case report

    Get PDF
    Coronary angiography is considered to be the gold standard technique for assessing the severity of obstructive luminal narrowing; however, in a few circumstances it may be misleading. In these cases, cardiac computed tomography (CT) and intravascular ultrasound (IVUS) may help to give a correct interpretation

    Identification of the chromosome complement and the spontaneous 1R/1V translocations in allotetraploid Secale cereale × Dasypyrum villosum hybrids through cytogenetic approaches

    Get PDF
    Genome modifications that occur at the initial interspecific hybridization event are dynamic and can be consolidated during the process of stabilization in successive generations of allopolyploids. This study identifies the number and chromosomal location of ribosomal DNA (rDNA) sites between Secale cereale, Dasypyrum villosum, and their allotetraploid S. cereale × D. villosum hybrids. For the first time, we show the advantages of FISH to reveal chromosome rearrangements in the tetraploid Secale × Dasypyrum hybrids. Based on the specific hybridization patterns of ribosomal 5S, 35S DNA and rye species-specific pSc200 DNA probes, a set of genotypes with numerous Secale/Dasypyrum translocations of 1R/1V chromosomes were identified in successive generations of allotetraploid S. cereale × D. villosum hybrids. In addition we analyse rye chromosome pairs using FISH with chromosome-specific DNA sequences on S. cereale × D. villosum hybrids

    The clinical features of the piriformis syndrome: a systematic review

    Get PDF
    Piriformis syndrome, sciatica caused by compression of the sciatic nerve by the piriformis muscle, has been described for over 70 years; yet, it remains controversial. The literature consists mainly of case series and narrative reviews. The objectives of the study were: first, to make the best use of existing evidence to estimate the frequencies of clinical features in patients reported to have PS; second, to identify future research questions. A systematic review was conducted of any study type that reported extractable data relevant to diagnosis. The search included all studies up to 1 March 2008 in four databases: AMED, CINAHL, Embase and Medline. Screening, data extraction and analysis were all performed independently by two reviewers. A total of 55 studies were included: 51 individual and 3 aggregated data studies, and 1 combined study. The most common features found were: buttock pain, external tenderness over the greater sciatic notch, aggravation of the pain through sitting and augmentation of the pain with manoeuvres that increase piriformis muscle tension. Future research could start with comparing the frequencies of these features in sciatica patients with and without disc herniation or spinal stenosis

    Massively Parallel RNA Chemical Mapping with a Reduced Bias MAP-seq Protocol

    Full text link
    Chemical mapping methods probe RNA structure by revealing and leveraging correlations of a nucleotide's structural accessibility or flexibility with its reactivity to various chemical probes. Pioneering work by Lucks and colleagues has expanded this method to probe hundreds of molecules at once on an Illumina sequencing platform, obviating the use of slab gels or capillary electrophoresis on one molecule at a time. Here, we describe optimizations to this method from our lab, resulting in the MAP-seq protocol (Multiplexed Accessibility Probing read out through sequencing), version 1.0. The protocol permits the quantitative probing of thousands of RNAs at once, by several chemical modification reagents, on the time scale of a day using a table-top Illumina machine. This method and a software package MAPseeker (http://simtk.org/home/map_seeker) address several potential sources of bias, by eliminating PCR steps, improving ligation efficiencies of ssDNA adapters, and avoiding problematic heuristics in prior algorithms. We hope that the step-by-step description of MAP-seq 1.0 will help other RNA mapping laboratories to transition from electrophoretic to next-generation sequencing methods and to further reduce the turnaround time and any remaining biases of the protocol.Comment: 22 pages, 5 figure
    corecore