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51.
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic pulmonary infection/inflammation which leads to respiratory failure. The presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has previously been observed in the sera of patients with CF. In view of the known relationship of ANCA with primary vasculitis and of their putative pathogenetic role in these disorders, we studied the presence, specificity and isotype of ANCA and their clinical associations in 66 adult CF patients. None of the 66 CF samples had autoantibodies to the major ANCA antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples contained IgG and 55/66 (83%) IgA, autoantibodies to bactericidal/permeability increasing protein (BPI), a recently characterized ANCA specificity. All the IgA anti-BPI-positive samples were also IgG anti-BPI-positive. The autoantibody specificity was confirmed by inhibition assay and immunoblotting of CF sera against a neutrophil granule preparation. Furthermore, in this cross-sectional study, anti-BPI levels were inversely correlated with the observed reductions in FEV1 and FVC (IgA anti-BPI and FEV1: r = 0.508, <it>p</it> &lt; 0.0001), and both IgG and IgA anti-BPI levels were higher in CF patients with secondary vasculitis (<it>n</it> = 6) than in those without (<it>p</it> &lt; 0.05). ANCA with specificity for BPI were present in the majority of CF sera in this study and autoimmune processes may be associated with the development of pulmonary injury in CF.   相似文献   
52.
This study examines the role of endothelial leukocyte adhesion molecule-1 (ELAM-1) in the development of the acute airway inflammation (cell influx) and late-phase airway obstruction in a primate model of extrinsic asthma. In animals sensitive to antigen, a single inhalation exposure induced the rapid expression of ELAM-1 (6 h) exclusively on vascular endothelium that correlated with the influx of neutrophils into the lungs and the onset of late-phase airway obstruction. In contrast, basal levels of ICAM-1 was constitutively expressed on vascular endothelium and airway epithelium before antigen challenge. After the single antigen exposure, changes in ICAM-1 expression did not correlate with neutrophil influx or the change in airway caliber. This was confirmed by showing that pretreatment with a monoclonal antibody to ICAM-1 did not inhibit the acute influx of neutrophils associated with late-phase airway obstruction, whereas a monoclonal antibody to ELAM-1 blocked both the influx of neutrophils and the late-phase airway obstruction. This study demonstrates a functional role for ELAM-1 in the development of acute airway inflammation in vivo. We conclude that, in primates, the late-phase response is the result of an ELAM-1 dependent influx of neutrophils. Therefore, the regulation of ELAM-1 expression may provide a novel approach to controlling the acute inflammatory response, and thereby, affecting airway function associated with inflammatory disorders, including asthma.  相似文献   
53.
We have examined the effects of direct intratracheal instillation of purified eosinophil granule proteins on pulmonary function and airway responsiveness in primates. The results of this study show for the first time that installation of major basic protein (MBP) directly into the trachea of primates results in a significant and dose-related increase in airway responsiveness to inhaled methacholine. Furthermore, MBP and eosinophil peroxidase (EPO) induce a transient bronchoconstriction immediately after instillation that resolves by 1 h postinstillation. In contrast, instillation of other eosinophil granule proteins had no effect on airway responsiveness or pulmonary function. These data indicate a direct role of the eosinophil in the pathogenesis of airway hyperresponsiveness. We suggest that the MBP of human eosinophils has an effector role in the pathogenesis of airway hyperresponsiveness which may involve active interaction with resident airway tissue cells. MBP may also mediate altered lung function in various inflammatory lung diseases associated with pulmonary eosinophilia.  相似文献   
54.

Background and purpose:

Tobacco smoke represents a relevant risk factor for coronary heart disease (CHD). Although peroxisome proliferator-activated receptor (PPAR)γ activation reduces inflammation and atherosclerosis, expression of PPARγ in cells and its modulation by smoking are poorly investigated. We previously reported that monocyte/macrophages from healthy smokers exhibited an enhanced constitutive expression of PPARγ. Here, we evaluated PPARγ expression and basal cytokine release in monocytes and monocyte-derived macrophages (MDMs) from 85 CHD patients, classified by their smoking habit (smokers, non-smokers and ex-smokers), and assessed the role of PPARγ ligands in this context.

Experimental approach:

PPARγ protein was detected by Western blot and semi-quantified by PPARγ/β-actin ratio; cytokine release was measured by elisa and nuclear factor-kappaB (NF-κB) translocation by electrophoretic mobility shift assays.

Key results:

As compared to the other groups, MDMs from smoker CHD patients exhibited a reduced PPARγ/β-actin ratio and an increased spontaneous release of tumour necrosis factor-α (TNF-α) and interleukin-6, but with no major variations in monocytes. In cells from selected CHD patients, rosiglitazone inhibited TNF-α release and NF-κB translocation induced by phorbol-12-myristate 13-acetate. The selective PPARγ antagonist GW9662 reversed these effects, with some variations related to smoking habit.

Conclusions and implications:

In CHD patients, exposure to tobacco smoke profoundly affected PPARγ expression, and this was related to levels of secretion of pro-inflammatory cytokines. MDMs from CHD smokers showed the lowest PPARγ expression and released more inflammatory cytokines. Moreover, rosiglitazone''s ability to inhibit cytokine release and its reversal by GW9662 clearly indicated PPARγ involvement in these changes in CHD patients.  相似文献   
55.
Systemic sclerosis (SSc) is an autoimmune systemic disease characterized by small vessel involvement that leads to tissue ischemia and fibroblast stimulation resulting in accumulation of collagen (fibrosis) in the skin and internal organs. Lipomembranous panniculitis is a peculiar type of fat necrosis and has been reported with clinical conditions, commonly with peripheral vascular diseases. We describe a case of a 43‐year‐old woman with SSc manifestations, who presented with black scaly skin plaques, associated with thickening of the subcutaneous fat tissue, on the lateral surface of her thighs, her calves, gluteal area and lower abdomen. Biopsy revealed lipomembranous panniculitis. Lipomembranous changes have been seen in connective tissue disorders such as lupus profundus, morphea, systemic sclerosis and panniculitis associated with dermatomyositis, but rarely in thighs, calves, gluteal area and lower abdomen. Almeida MSTM, Lima SCB, Carvalho LL, Almeida JVM, Santos LG, Rolim JRA, Rocha TE. Panniculitis–An unusual cutaneous manifestation of systemic sclerosis.  相似文献   
56.
57.
Hahn  PF; Stark  DD; Vici  LG; Ferrucci  JT  Jr 《Radiology》1986,159(2):379-382
Proper management of duodenal hematoma requires that an accurate diagnosis be made using noninvasive radiological methods. Conventional imaging may be nonspecific if there is no history of trauma or coagulopathy. Two cases of duodenal hematoma that were imaged by magnetic resonance (MR) and computed tomography (CT) are described. In both cases the hematoma had a well-defined concentric ring configuration on MR images, a finding which helped establish the diagnosis. MR imaging may provide tissue-specific characterization of duodenal hematomas.  相似文献   
58.

Background

The pathophysiological changes of COPD tend to worsen with progression, triggering limiting symptoms and implying the decrease in the activities of daily living and quality of life. The COPD Assessment Test (CAT) is a questionnaire designed to measure the impact of COPD on the health status. The aim of this study was to evaluate the impact of the disease through the CAT in a Brazilian sample of COPD patients and to correlate symptoms at rest with the CAT score in these patients.

Methods

Study of cases with COPD patients was conducted by pulmonary rehabilitation program (RP). Respiratory rate (RR) and symptoms (dyspnea by Modified Borg Scale Dyspnea Index; symptoms by CAT) were analyzed at the beginning of the RP.

Results

The study analyzed 28 COPD patients, both genders, age 65.93?±?7.84 years and many patients ranging from severe and very severe disease. The majority of patients were rated by CAT with low impact-disease (n?=?13/46, 4%);medium (n?=?11/39, 3%) and the high impact-diseases were observed in a few subjects (n?=?4/14.3%). The difference between all CAT scores was significant, p?=?0.000. There was a positive correlation between respiratory rate and CAT scores impact-level (r?=?0.585, p?=?0.001). The results obtained by the Borg Scale revealed a high presence of symptoms in these COPD patients but no association with CAT.

Conclusion

The CAT is a sensitive tool to assess the current health status of COPD patients, and in Southern Brazil it is positively correlated with respiratory rate.
  相似文献   
59.
Abstrakt  Gründen ?rzte nur deshalb eine Gesellschaft bürgerlichen Rechts, um einem Arzt Gelegenheit zu geben, an Erl?sen beteiligt zu werden, die der andere Arzt mit Leistungen erwirtschaftet, die der beteiligte Arzt mangels eigener Qualifikation nicht erbringen darf, und fehlt es weiter an den wesentlichen Merkmalen einer Berufsausübungsgemeinschaft, ist der zugrunde liegende “Gesellschaftsvertrag” wegen Versto?es gegen § 134 BGB nichtig. (Leitsatz des Bearbeiters)  相似文献   
60.
An evidence-based review was undertaken to answer the question, "What is the evidence for the effect of interventions designed to establish, modify, and maintain activities of daily living (ADLs), instrumental activities of daily living (IADLs), leisure, and social participation on quality of life (QOL), health and wellness, and client and caregiver satisfaction for people with Alzheimer's disease and related dementias?" A systematic search of electronic databases and application of inclusion and exclusion criteria guided the selection of 26 articles. Limited high-level evidence on ADL interventions was identified. IADL interventions for people living in the community showed promise. Tailored and activity-based leisure interventions were common and seemed to have positive impacts on caregiver satisfaction, and some interventions had positive results for client well-being and QOL. Social participation interventions focused on people with dementia still able to engage in verbal social interactions; these interventions had at least short-term positive effects.  相似文献   
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