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61.
ObjectiveTo verify the impact of ischemic time on lung cell viability in an experimental model of lung ischemia–reperfusion (IR) injury and its repercussion on lung performance after reperfusion.MethodsTwenty-four animals were subjected to selective clamping of the left pulmonary artery and divided into four groups (n = 6) according to ischemic time: 15 (IR15), 30 (IR30), 45 (IR45), and 60 min (IR60). All animals were observed for 120 min after reperfusion. The hemodynamics, arterial blood gases measurements, and histologic changes were analyzed. Immunofluorescence assays for caspase 3 and annexin V were performed. Lipid peroxidation was assessed by thiobarbituric acid–reactive substances, and caspase 3 activity was assessed by colorimetric extract.ResultsThe partial pressure of arterial oxygen significantly decreased at the end of the observation period in the IR30, IR45, and IR60 groups (P < 0.05). The final mean arterial pressure significantly decreased in the IR60 group (P < 0.05). We observed a significant increase in caspase 3 activity and caspase 3–positive cells by immunofluorescence in the IR45 group compared with the other groups (P < 0.05). Additionally, there was an increase in necrotic cells assessed by annexin V in the IR60 group. The histologic score did not show differences among the different groups.ConclusionsThe degree of cell damage had a negative impact on lung performance. Sixty minutes of lung ischemia and posterior reperfusion resulted in an increased number of necrotic cells, suggesting that these cells may not be able to reverse the effects of the IR injury because of the lack of viable cells.  相似文献   
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Purpose  

We have little knowledge about the evolution of emphysema, and relatively little is understood about its evolution in relation to smoking habits. This study aims to assess the evolution of emphysema in asymptomatic current and former smokers over 2 years and to investigate the association with subjects’ characteristics. The study was approved by our Ethics Committee and all participants provided written informed consent.  相似文献   
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BACKGROUND/AIMS: Data regarding hepatitis B virus (HBV) genomic heterogeneity in perinatal infection are incomplete, although HBV variants might be involved in neonatal fulminant hepatitis (ALF). We investigated HBV variability in infected babies showing different clinical courses. METHODS: We analyzed HBV genomes isolated from nine vertically infected babies and the mothers of four of them. Two infants born to HBe-antigen (HBeAg)-positive women developed a chronic infection; seven babies (six born to anti-HBe mothers) developed acute hepatitis that had a fulminant course in four cases and a benign course in three. Two babies developing ALF received anti-HBV immunoprophylaxis at birth. RESULTS: Viruses carrying no significant mutation infected infants born to HBeAg-positive women. HBeAg-defective viruses were detected both in children with benign and fulminant hepatitis and their mothers. A double nucleotide mutation at positions 1762 and 1764 of the HBV core-promoter was found in two of the four infants with ALF, although it was not detected in isolates from the mother of one of them. No significant S gene mutation was found in HBV from any of the babies. CONCLUSIONS: This study indicates that HBV genomic heterogeneity is not primarily involved either in the evolution of the infection or the failure of neonatal HBV immunoprophylaxis.  相似文献   
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BACKGROUND: there is increasing evidence to support the efficacy of reality orientation in cognitive deficits in patients with Alzheimer's disease. The clinical characteristics of patients who respond to reality orientation are poorly understood; this knowledge could be important, given that the provision of reality orientation therapy is labour-intensive and may provoke emotional distress. AIM: to evaluate retrospectively which demographic and clinical characteristics of Alzheimer's patients predict cognitive outcomes. METHOD: we analysed 38 mild-to-moderately demented outpatients who regularly attended a one-month formal reality orientation programme. The mini mental state examination score changes from baseline-and immediately after-reality orientation were correlated with demographic and pre-treatment clinical characteristics by a linear regression analysis. RESULTS: short-term responsiveness to reality orientation was significantly predicted by a lower level of cognitive functioning (as measured by the mini mental state examination) at baseline and by the absence of euphoria, accounting together for 57.6% of variance. CONCLUSION: a lower mini mental state examination and the absence of euphoric behaviour in patients with mild-to-moderate Alzheimer's disease may predict a good cognitive outcome of reality orientation therapy.  相似文献   
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Primary lymphomatous effusions are defined as lymphomas presenting in the serous body cavities in the absence of clinically identifiable tumor masses. Recently, a peculiar type of primary lymphomatous effusion associated with tumor clone infection by human herpesvirus type 8 (HHV-8) and preferentially arising in HIV-positive patients has been described and termed as primary effusion lymphoma (PEL). This report describes a case of PEL which has developed in a HIV-negative, 92-year-old man with longstanding Mediterranean Kaposi's sarcoma, a disease also associated with HHV-8 infection. The patient presented with pleural and ascitic effusions in the absence of solid masses within the lungs, mediastinum, thoracic wall or abdominal cavity. The effusions consisted of malignant lymphocytes with morphologic features bridging immunoblastic and anaplastic cells. Immunophenotypic studies revealed that the lymphoma population expressed an antigenic profile consistent with PEL, i.e. the absence of common B- and T-cell markers (non-B, non-T phenotype) coupled to CD138 positivity. Molecular analysis demonstrated infection of the tumor clone by HHV-8 as well as monoclonally rearranged immunoglobulin genes, consistent with a B-cell histogenesis of the lymphoma. In addition, this PEL case harbored PAX-5 gene mutations, which have been recently demonstrated as a key feature of the proto-oncogene hypermutation process involved in the pathogenesis of some lymphoma types. Following two courses of etoposide and prednisone, a partial remission was achieved. The patient died of liver failure 3 months after the diagnosis of PEL. Overall, this case report illustrates the need for an integrated diagnostic approach based on clinical features, morphology, immunophenotype, and molecular genetics to primary lymphomatous effusions.  相似文献   
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BACKGROUND

Evidence suggests that expressed emotion (EE) and family burden (FB) are phenomena that interact, but there is a lack of studies that analyze this association in patients in first-episode psychosis.

AIM

This study evaluated the relationship between EE and FB in relatives of patients in first-episode psychosis.

METHOD

A convenience sample of 71 family members of patients being assisted in an outpatient care unit participated in the study. We used a form with sociodemographic and clinical variables of family members and patients, the Family Questionnaire-Brazilian Portuguese Version and the Brazilian version of the Burden Interview. The data were obtained via semi-structured interviews. Statistical analyses included Fisher's exact tests, Mann Whitney tests, Spearman correlations, and Student's t-tests.

RESULTS

Our results showed high levels of EE and its component emotional over-involvement (EOI) among relatives, and a strong correlation between critical comments (CC) and EOI and FB measurements. In addition, family members with elevated EE levels showed higher means for FB and this difference was significant.

CONCLUSIONS

Mental health nurses are expected to consider these concepts for proposing nursing interventions to first-episode psychosis patients and their relatives.  相似文献   
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