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21.
Trkanjec JT Peros-Golubicić T Grozdek D Ivicević A Alilović M 《Collegium antropologicum》2003,27(2):669-675
Transbronchial lung biopsy (TBLB) is a well-recognized diagnostic technique in diffuse interstitial lung diseases, but it is not considered to be the first choice in investigation of solitary pulmonary nodules (SPN). The main idea of this study was to increase the sensitivity of bronchoscopy using multiple techniques, especially TBLB, thus to avoid more aggressive diagnostic procedures. The objective of this prospective study was to evaluate the efficacy and safety of TBLB in the diagnosis of SPN, in comparison with other bronchoscopic techniques. Fifty patients with chest x-ray finding consistent with SPN underwent bronchoscopy with bronchial washing, brushing, bronchoalveolar lavage (BAL) and TBLB were included in this study. Thirty-one patients suffered from malignant tumors, while 19 patients had nonmalignant lesions. TBLB achieved overall diagnostic sensitivity of 62%, BAL of 29%, bronchial brushing of 16% and washing of 6%. Combining all techniques together, bronchoscopy had overall sensitivity of 86%. Concerning malignant lesions, TBLB had a sensitivity of 65%, specificity of 100%, and accuracy of 82%. TBLB had a significantly better yield for lesions with a diameter > or = 25 mm than for lesions of < 25 mm (sensitivity of 82% and 53% respectively, p < 0.05). Diagnostic yield improved significantly with the increasing number of specimens (less than 3 specimens: sensitivity 59%, 3 or more specimens: sensitivity 87%, p < 0.05). Complications of TBLB occurred in 2 (4%) patients: 1 incomplete pneumothorax and 1 hemorrhage. According to the results, we conclude that TBLB is an accurate and safe technique for the diagnosis of pulmonary solitary nodule with a diameter equal or greater than 25 mm. 相似文献
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Grace Y. Lam Marija Cemma Aleixo M. Muise Darren E. Higgins John H. Brumell 《Autophagy》2013,9(7):985-995
Listeria monocytogenes is a bacterial pathogen that can escape the phagosome and replicate in the cytosol of host cells during infection. We previously observed that a population (up to 35%) of L. monocytogenes strain 10403S colocalize with the macroautophagy marker LC3 at 1 h postinfection. This is thought to give rise to spacious Listeria-containing phagosomes (SLAPs), a membrane-bound compartment harboring slow-growing bacteria that is associated with persistent infection. Here, we examined the host and bacterial factors that mediate LC3 recruitment to bacteria at 1 h postinfection. At this early time point, LC3+ bacteria were present within single-membrane phagosomes that are LAMP1+. Protein ubiquitination is known to play a role in targeting cytosolic L. monocytogenes to macroautophagy. However, we found that neither protein ubiquitination nor the ubiquitin-binding adaptor SQSTM1/p62 are associated with LC3+ bacteria at 1 h postinfection. Reactive oxygen species (ROS) production by the CYBB/NOX2 NADPH oxidase was also required for LC3 recruitment to bacteria at 1 h postinfection and for subsequent SLAP formation. Diacylglycerol is an upstream activator of the CYBB/NOX2 NADPH oxidase, and its production by both bacterial and host phospholipases was required for LC3 recruitment to bacteria. Our data suggest that the LC3-associated phagocytosis (LAP) pathway, which is distinct from macroautophagy, targets L. monocytogenes during the early stage of infection within host macrophages and allows establishment of an intracellular niche (SLAPs) associated with persistent infection. 相似文献
24.
Vukicevic M Weder G Boillat A Boesch A Kellenberger S 《The Journal of biological chemistry》2006,281(2):714-722
Acid-sensing ion channels (ASICs) are neuronal Na(+) channels that are members of the epithelial Na(+) channel/degenerin family and are transiently activated by extracellular acidification. ASICs in the central nervous system have a modulatory role in synaptic transmission and are involved in cell injury induced by acidosis. We have recently demonstrated that ASIC function is regulated by serine proteases. We provide here evidence that this regulation of ASIC function is tightly linked to channel cleavage. Trypsin cleaves ASIC1a with a similar time course as it changes ASIC1a function, whereas ASIC1b, whose function is not modified by trypsin, is not cleaved. Trypsin cleaves ASIC1a at Arg-145, in the N-terminal part of the extracellular loop, between a highly conserved sequence and a sequence that is critical for ASIC1a inhibition by the venom of the tarantula Psalmopoeus cambridgei. This channel domain controls the inactivation kinetics and co-determines the pH dependence of ASIC gating. It undergoes a conformational change during inactivation, which renders the cleavage site inaccessible to trypsin in inactivated channels. 相似文献
25.
For the general public, but also for healthcare professionals, schizophrenia is still one of those areas of medicine connected with feelings of unease, fear and prejudice. These feelings lead to stigmatization and discrimination which are unjust processes which put patients suffering from mental illnesses into undesirable and unequal positions. Aim of this research was to establish the extent of stigmatization of mentally ill patients among the population of healthcare professionals and future healthcare professionals and if they differ from general population. Results show that stigmatization of schizophrenic patients is high among all included populations. Although there were no statistical differences between groups regarding the assessment of schizophrenic patients, nurses employed in psychiatric wards exhibited a tendency towards higher acceptance of schizophrenic patients, as well as better understanding of that illness. This data emphasizes a growing need for continuous education of general population but also of healthcare professionals. 相似文献
26.
Ante Žuljević Thierry Thibaut Marija Despalatović Jean-Michel Cottalorda Vedran Nikolić Ivan Cvitković Boris Antolić 《Biological invasions》2011,13(10):2303-2308
Here we present the first observation of the impact of the invasive Caulerpa racemosa var. cylindracea on native photophilic sponge species in the Adriatic Sea, with special focus on Sarcotragus spinosulus. Caulerpa racemosa var. cylindracea is able to completely overgrow the sponge, developing an exceptionally thick canopy with a maximum measured density of 1,887 m
of stolons m−2 and 40,561 fronds m−2. Necrosis of the sponge surface was significantly correlated with the algal dry biomass, frond number and stolon length.
Dense algal canopy, penetration of the algal stolon and rhizoids into the sponge oscula and covering of the ostiae probably
diminishes the seawater circulation through the sponge and consequently results in its smothering and even death. We suggest
that chemotropism is the reason why C. racemosa penetrates the sponge oscula and establishes such dense canopy on the sponge. 相似文献
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