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Jasmine Martinez Christine Liu Nyah Rodman Jennifer S. Fernandez Claudia Barberis Rodrigo Sieira Federico Perez Robert A. Bonomo Maria Soledad Ramirez 《Diagnostic microbiology and infectious disease》2019,93(3):183-187
Transformation is one of the mechanisms of acquisition of foreign genetic material leading to the emergence of multidrug resistant (MDR) bacteria. Recently, human serum albumin (HSA) was shown to specifically increase transformation frequency in the nosocomial pathogen Acinetobacter baumannii. To further assess the relevance of HSA as a possible modulator of A. baumannii transformation in host-pathogen interactions, in this work we examined the effect of different human fluids. We observed a significant increase in transformation frequencies in the presence of pleural fluid, whole blood cells and liquid ascites, and to a lesser extent with urine. The observed effects correlate with both HSA and bacterial content found in the assayed patient fluids. Taken together, these results are in agreement with our previous findings that highlight HSA as a possible host signal with the ability to trigger natural transformation in A. baumannii. 相似文献
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Alice Song Edson Abdala Daniel Waisberg Rodrigo Bronze Martino Ho Yeh Li Luiz Marcelo Sa Malbouisson Ryan Yukimatsu Tanigawa Amaro Duarte Neto Guilherme Marques Andrade Liliana Ducatti Andre Mario Doi João Renato Rebello Pinho Michele Gomes‐Gouvea Fernanda Malta Lecio Figueira Pinto Bruno Fukelmann Guedes Luciana Haddad Venancio Avancini F. Alves Luiz Augusto D. Albuquerque 《The Brazilian journal of infectious diseases》2018
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At present, the majority of surgical heart valves (SHVs) implanted are bioprosthetic valves. Over time however, these are prone to structural deterioration, which may manifest as valvular stenosis, regurgitation or a combination of the two. Re-operation is the current standard of care for these patients but this itself carries a significant risk of mortality and morbidity. As a natural extension of transcatheter aortic valve implantation (TAVI), now an evidence based solution for severe aortic stenosis in high-risk patients, valve-in-valve (VIV) therapy is evolving into an alternative option in selected patients with structural biological valvular deterioration in all four-valve positions. The first of these VIV procedures was performed in Germany in 2007, for failing aortic valve prosthesis and later, reported in other positions. As with any novel emerging therapy, there is a learning curve to the procedure and the operator must be aware of the potential challenges. In this review we describe some of these challenges with the aim of providing awareness as well as guidance on attaining a successful outcome. 相似文献
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Hector R. Galván-Salazar Alejandro Arreola-Cruz Daniela Madrigal-Pérez Alejandro D. Soriano-Hernández Jose Guzman-Esquivel Daniel A. Montes-Galindo Rodrigo A. López-Flores Francisco Espinoza-Gomez Iram P. Rodríguez-Sanchez Oscar A. Newton-Sanchez Agustin Lara-Esqueda Margarita L. Martinez-Fierro Xochitl G. Brise?o-Gomez Ivan Delgado-Enciso 《Breast care (Basel, Switzerland)》2015,10(6):393-396
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Abstract During pulmonary rehabilitation, a subset of subjects with COPD requires adjunct therapy to achieve high-intensity training. Both noninvasive ventilation (NIV) and inspiratory muscle training (IMT) are available to assist these subjects. We aimed to prime the respiratory muscles before NIV with IMT, anticipating additive effects for maximal exercise tolerance (T lim) and dyspnea/leg fatigue relief throughout the exercise as primary outcomes. Changes in the respiratory pattern were secondary outcomes. COPD subjects performed a total of four identical constant work rate tests on a cycle ergometer at 75% of maximum work rate, under control ventilation (SHAM, 4?cm H2O) or proportional assisted ventilation (PAV, individually adjusted), before and after 10 sessions of high-intensity IMT (three times/week) during 30?days. Two-way RM ANOVA with appropriate corrections were performed. Final analysis in nine subjects showed improved T lim (Δ = 111?s) and lower minute-ventilation (Δ = 4?L.min?1) at exhaustion, when comparing the IMT effects within the PAV modality (p?=?0.001 and p?=?0.036, respectively) and improved T lim for PAV vs. SHAM (PAV main-effect, p?=?0.001; IMT main-effect, p?=?0.006; PAV vs. IMT interaction, p?=?0.034). In addition, IMT?+?PAV association, compared to PAV alone, resulted in lower respiratory frequency (IMT main-effect, p?=?0.009; time main-effect, p?<?0.0001; IMT vs. time interaction, p?=?0.242) and lower inspiratory time related to duty cycle (IMT main-effect, p?=?0.018; time main-effect, p?=?0.0001; IMT vs. time interaction, p?=?0.004) throughout exercise. The addition of IMT prior to a PAV-supported aerobic bout potentiates exercise tolerance and dyspnea relief and induces favourable changes in ventilatory pattern in severe COPD during high-intensity training (Brazilian Registry of Clinical Trials, number RBR-6n3dzz). 相似文献
107.
Natália A. Gonzaga Gabriel T. do Vale Juliana M. Parente Rodrigo Yokota Bruno S. De Martinis Dulce E. Casarini Michele M. Castro Carlos R. Tirapelli 《Journal of the American Society of Hypertension》2018,12(7):561-573
We evaluated the possible mechanisms underlying the oxidative stress induced by ethanol withdrawal. With this purpose, we verified the role of AT1 receptors in such response. Male Wistar rats were treated with ethanol 3%–9% (vol./vol.) for 21 days. Ethanol withdrawal was induced by abrupt discontinuation of the treatment. Experiments were performed 48 hours after ethanol discontinuation. Increased plasma levels of angiotensin II were detected after ethanol withdrawal. Losartan (10 mg/kg; p.o. gavage), a selective AT1 receptor antagonist, impeded the increase in blood pressure induced by ethanol withdrawal. Increased lipoperoxidation and superoxide anion (O2?) levels were detected in aortas after ethanol withdrawal, and losartan prevented these responses. Decreased hydrogen peroxide and nitrate/nitrite concentration were detected in aortas after ethanol withdrawal, and losartan prevented these effects. Nitrotyrosine immunostaining in the rat aorta was increased after ethanol withdrawal, and AT1 blockade impeded this response. Increased expression of PKCδ and p47phox was detected after ethanol withdrawal, and treatment with losartan prevented these responses. Our study provides novel evidence that ethanol withdrawal increases vascular oxidative stress and blood pressure through AT1-dependent mechanisms. These findings highlight the importance of angiotensin II in ethanol withdrawal–induced increase in blood pressure and vascular oxidative damage. 相似文献
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Insertion of an Edwards Sapien 3 prosthesis as a mitral valve in valve implantation via a transapical approach 下载免费PDF全文