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101.
Lucía Yim Sebastián Sasías Arací Martínez Laura Betancor Verónica Estevez Paola Scavone Alejandro Bielli Alfredo Sirok José Alejandro Chabalgoity 《Infection and immunity》2014,82(4):1465-1476
The nontyphoidal Salmonella enterica serovar Dublin is adapted to cattle but infrequently infects humans, very often resulting in invasive infections with high levels of morbidity and mortality. A Salmonella-induced intestinal acute inflammatory response is postulated as a mechanism to prevent bacterial dissemination to systemic sites. In S. enterica serovar Typhimurium, flagella contribute to this response by providing motility and FliC-mediated activation of pattern recognition receptors. In this study, we found 4 Salmonella enterica isolates, with the antigenic formula 9,12:−:−, that, based on fliC sequence and multilocus sequence type (MLST) analyses, are aflagellate S. Dublin isolates. Interestingly, all were obtained from human bloodstream infections. Thus, we investigated the potential role of flagella in the unusual invasiveness exhibited by S. Dublin in humans by analyzing flagellation and proinflammatory properties of a collection of 10 S. Dublin human clinical isolates. We found that 4 of 7 blood isolates were aflagellate due to significantly reduced levels of fliC expression, whereas all 3 isolates from other sources were flagellated. Lack of flagella correlated with a reduced ability of triggering interleukin-8 (IL-8) and CCL20 chemokine expression in human intestinal Caco-2 cells and with reduced early inflammation in the ceca of streptomycin-pretreated C57/BL6 mice. These results indicate that flagella contribute to the host intestinal inflammatory response to Salmonella serovar Dublin and suggest that their absence may contribute to its systemic dissemination through dampening of the gut immune response. Analysis of FliC production in a collection of cattle isolates indicated that the aflagellate phenotype is widely distributed in field isolates of S. Dublin. 相似文献
102.
Calogero Puntrello Fabiana Lucà Gaspare Rubino Carmelo Massimiliano Rao Sandro Gelsomino 《World journal of cardiology》2014,6(9):1041-1044
We present the case of a young woman corrected with a Mustard procedure undergoing successful transvenous double chamber pacemaker implantation with the atrial lead placed in the systemic venous channel. The case presented demonstrates that, when the systemic venous atrium is separate from the left atrial appendage, the lead can be easily and safely placed in the systemic venous left atrium gaining satisfactory sensing and pacing thresholds despite consisting partially of pericardial tissue. 相似文献
103.
Ricardo Petraco Rasha Al-Lamee Matthias Gotberg Andrew Sharp Farrel Hellig Sukhjinder S. Nijjer Mauro Echavarria-Pinto Tim P. van de Hoef Sayan Sen Nobuhiro Tanaka Eric Van Belle Waldemar Bojara Kunihiro Sakoda Martin Mates Ciro Indolfi Salvatore De Rosa Christian J. Vrints Steven Haine Hiroyoshi Yokoi Flavio L. Ribichini Martjin Meuwissen Hitoshi Matsuo Luc Janssens Ueno Katsumi Carlo Di Mario Javier Escaned Jan Piek Justin E. Davies 《American heart journal》2014
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Healthcare professionals and managers in hospitals are frequently suggested to learn from industry and business to improve quality and efficiency. However, evidence that the implementation of industrial techniques and business methods has a meaningful effect on patient outcomes is often lacking. An explanation for this phenomenon is thought to be the complexity of the hospital organisation and the diversity of patients. In this article, we use the practice approach to discuss the application of industrial techniques and business methods in healthcare. We employ a practice model that offers three perspectives to understand professional practices: Identity and intrinsic values, Interests of stakeholders, and Ideals and basic beliefs (Triple I). This model demonstrates that the nature of healthcare practices differs strongly from the nature of industrial and business practices. Healthcare has a moral nature that does not let itself be easily organised along technological or business categories. This may provide a fundamental explanation of why industrial techniques and business methods in general will be less successful in healthcare. At the same time, this model invites hospitals to develop innovative approaches that do justice to the identity and intrinsic values of healthcare. In this process, insights from industry and business cannot be copied but have to be used as sources of inspiration. 相似文献
107.
Experimental data indicate that apoptosis is activated in the aged skeletal muscle, contributing to sarcopenia. We have previously demonstrated that testosterone protects against hydrogen peroxide (H(2)O(2))-induced apoptosis in C2C12 muscle cells. Here we identified molecular events involved in the antiapoptotic effect of testosterone. At short times of exposure to H(2)O(2) cells exhibit a defense response but at longer treatment times cells undergo apoptosis. Incubation with testosterone prior to H(2)O(2) induces BAD inactivation, inhibition of poly(ADP-ribose) polymerase cleavage, and a decrease in BAX levels, and impedes the loss of mitochondrial membrane potential, suggesting that the hormone participates in the regulation of the apoptotic intrinsic pathway. Simultaneous treatment with testosterone, H(2)O(2), and the androgen receptor (AR) antagonist, flutamide, reduces the effects of the hormone, pointing to a possible participation of the AR in the antiapoptotic effect. The data presented allow us to begin to elucidate the mechanism by which the hormone prevents apoptosis in skeletal muscle. 相似文献
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Lemmert ME de Vreede-Swagemakers JJ Eurlings LW Kalb L Crijns HJ Wellens HJ Gorgels AP 《The American journal of cardiology》2012,109(9):1278-1282
Sudden cardiac arrest (SCA), due mainly to coronary artery disease (CAD), is a leading cause of death. To identify electrocardiographic and clinical differences between patients with CAD with and without SCA, 87 victims of SCA with CAD were compared with 131 patients with CAD without SCA. Patients' latest routine electrocardiograms and clinical variables were compared. Patients with CAD with and without previous myocardial infarctions (MIs) were included. Patients with SCA had a higher incidence of echocardiographic evidence of left ventricular hypertrophy and/or heart failure than controls. The median left ventricular ejection fractions for patients with SCA with and without previous MIs were 0.30 (interquartile range 0.24 to 0.41) and 0.41 (interquartile range 0.25 to 0.56). The median time between the last electrocardiographic assessment and SCA was 59 days (interquartile range 29 to 137). Regarding electrocardiographic characteristics, in patients with and without previous MIs, QRS width (odds ratio 1.032, 95% confidence interval 1.012 to 1.053, p = 0.002, and odds ratio 1.035, 95% confidence interval 1.015 to 1.056, p = 0.001) was the only significant predictor of SCA. In conclusion, in patients with CAD, regardless of a previous MI, a longer QRS width and echocardiographic parameters consistent with heart failure are associated with SCA, even in patients with ischemic cardiomyopathy currently not eligible for an implantable cardioverter-defibrillator. 相似文献