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Abnormalities in lungs caused by emphysema might alter their response to sepsis and the occurrence of acute lung injury (ALI). This study compared the extension of ALI in response to intraperitoneal lipopolysaccharide (LPS) injection in Wistar rats with and without emphysema induced by elastase. Adult male Wistar rats were randomized into four groups: control, emphysema without sepsis, normal lung with sepsis and emphysema with sepsis. Sepsis was induced, and 24 h later the rats were euthanised. The following analysis was performed: blood gas measurements, bronchoalveolar lavage (BAL), lung permeability and histology. Animals that received LPS showed significant increase in a lung injury scoring system, inflammatory cells in bronchoalveolar lavage (BAL) and IL‐6, TNF‐α and CXCL2 mRNA expression in lung tissue. Animals with emphysema and sepsis showed increased alveolocapillary membrane permeability, demonstrated by higher BAL/serum albumin ratio. In conclusion, the presence of emphysema induced by elastase increases the inflammatory response in the lungs to a systemic stimulus, represented in this model by the intraperitoneal injection of LPS.  相似文献   
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Unilateral papillitis caused by Treponema pallidum was found in an immunocompetent homosexual patient with severe vision loss who had received previous antibiotics treatment. Syphilis-related ocular manifestation is more common in the early stages of the disease and it can be associated with a central nervous system localization. In this patient, neurosyphilis was diagnosed on the basis of clinical and laboratory findings. Optical examination revealed unilateral papillitis in the left eye and no relative afferent pupillary defects. The patient underwent visual field examinations with conventional perimetry using the 30-2 program of the Humphrey Visual Field Analyzer, which indicated a blind spot enlargement in the left eye. Optical coherence tomography, visual evoked potentials (VEP), and fluorescein angiograms revealed inflammation of the optic nerve head with edematous and blurred margins. A reactive T. pallidum hemagglutination assay with low rapid plasma reagin (RPR) serum titer was performed; an HIV antibody test and MRI of the orbits and head with contrast gave negative results. Resolution of the ocular inflammation after intravenous penicillin treatment was obtained. The reported case illustrates the importance of early recognition of this treatable disease. The rise of syphilis, especially in urban areas, necessitates a high level of suspicion when dealing with patients with intraocular inflammation of unknown origin. Lues serology should be incorporated into routine laboratory diagnostics to aid in the detection of such cases. Considering the re-emergence of syphilis, screening of migrants from countries with high syphilis seroprevalences should be recommended.  相似文献   
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A tymovirus was isolated in Brazil from tomato plants with severe symptoms of leaf mosaic and blistering. The virus was mechanically transmissible to solanaceous indicator host species. The infected plants contained icosahedral particles and chloroplasts with membrane deformations which are typical cytopathic effects caused by tymoviruses. Its coat protein amino acid sequence shares the maximum of 64 % identity with the tymovirus Chiltepin yellow mosaic virus, which suggested that it can be considered as a distinct member of the genus Tymovirus. In a phylogenetic tree, this tymovirus was clustered with other solanaceous-infecting tymoviruses. It was tentatively named as Tomato blistering mosaic virus (ToBMV).  相似文献   
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During 2003–2012, 8 clusters of meningococcal disease were identified in Rio de Janeiro State, Brazil, all caused by serogroup C Neisseria meningitidis. The isolates were assigned to 3 clonal complexes (cc): cc11, cc32, and cc103. These hyperinvasive disease lineages were associated with endemic disease, outbreaks, and high case-fatality rates.  相似文献   
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Heteroresistance is the coexistence of populations with differing nucleotides at a drug resistance locus within a sample of organisms. Although Sanger sequencing is the gold standard for sequencing, it may be less sensitive than deep sequencing for detecting fluoroquinolone heteroresistance in Mycobacterium tuberculosis. Twenty-seven fluoroquinolone monoresistant and 11 fluoroquinolone-susceptible M. tuberculosis isolates were analyzed by Sanger and Illumina deep sequencing. Individual sequencing reads were analyzed to detect heteroresistance in the gyrA and gyrB genes. Heteroresistance to fluoroquinolones was identified in 10/26 (38%) phenotypically fluoroquinolone-resistant samples and 0/11 (P = 0.02) fluoroquinolone-susceptible controls. One resistant sample was excluded because of contamination with the laboratory strain M. tuberculosis H37Rv. Sanger sequencing revealed resistance-conferring mutations in 15 isolates, while deep sequencing revealed mutations in 20 isolates. Isolates with fluoroquinolone resistance-conferring mutations by Sanger sequencing all had at least those same mutations identified by deep sequencing. By deep sequencing, 10 isolates had a single fixed (defined as >95% frequency) mutation, while 10 were heteroresistant, 5 of which had a single unfixed (defined as <95% frequency) mutation and 5 had multiple unfixed mutations. Illumina deep sequencing identified a higher proportion of fluoroquinolone-resistant M. tuberculosis isolates with heteroresistance than did Sanger sequencing. The heteroresistant isolates frequently demonstrated multiple mutations, but resistant isolates with fixed mutations each had only a single mutation.  相似文献   
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