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91.
BACKGROUND: Infection of the gastric mucosa by helicobacter pylori is primarily responsible for gastritis, gastric ulcer, adenocarcinoma, and lymphoproliferative disorders. H. pylori appears to accelerate apoptosis and the proliferation of the gastric epithelium directly or indirectly. To precisely assess the proliferative and apoptotic profile of .H pylori-infected gastric mucosa, a quantitative imaging system is now required. METHODS: Fifty-two patients with H. pylori gastritis were the subjects of the study. Biopsy materials were taken from at least two sites (usually three to five sites) including the antrum and corpus. The grade of gastritis was evaluated by the updated Sydney System. The proliferative and apoptotic profile was examined by Ki-67 immunohistochemistry and by a terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling method. In addition, Ki-67-positive cells were quantitated by an image processor for analytical pathology (IPAP) system. RESULTS: H. pylori density and polymorphonuclear neutrophil activity were significantly decreased after H. pylori eradication ( P< 0.0001). Chronic inflammation (P< 0.0001) and lymphoid follicle numbers ( P < 0.0005) were also significantly decreased after the eradication. Glandular atrophy and intestinal metaplasia were slightly decreased after eradication, but the decrease did not reach the significant level. the Ki-67 labeling index was significantly decreased after the eradication P< 0.0001). The apoptosis index was also decreased after the eradication, but this decrease did not reach the significant level ( P = 0.06). CONCLUSION: our data suggest that the activation of proliferative cells and induction of apoptosis in the gastric mucosa is a response to H. pylori-induced mucosal damage. Moreover, IPAP may be a useful technology for evaluating the results of immunohistochemistry, and it could provide quantitative and reliable data for studying H. pylori gastritis.  相似文献   
92.
Frequent expression of bcl-2 protein in solitary fibrous tumors   总被引:3,自引:0,他引:3  
The distinction of solitary fibrous tumors from histologically similar neoplasms is often difficult because they rarely occur at a variety of extrapleural sites. CD34 immunoreactivity has recently been recognized to be an adjunct for the diagnosis of solitary fibrous tumors. However, it is now known that CD34 staining is not entirely specific for this entity. We evaluated 23 solitary fibrous tumors and 54 other spindle cell tumors often considered in the differential diagnosis for immunoreactivity using monoclonal antibodies directed against bcl-2 protein, which protects cells from apoptosis and CD34. The patients with solitary fibrous tumors comprised 11 men and 12 women, ranging in age from 35 to 85 years (mean, 57.6 years). Fourteen tumors arose in the pleura, four in the retroperitoneum, three in the superficial soft tissue and one each in the mediastinum and uterine cervix. Nineteen of 23 solitary fibrous tumors (83%), irrespective of tumor site, demonstrated diffuse cytoplasmic staining for bcl-2 protein. bcl-2 immunoreactivity was also observed in five of seven neurofibromas (71%), eight of 10 synovial sarcomas (80%) and one of three spindle cell lipomas (33%). CD34 immunoreactivity was present in all but one solitary fibrous tumor (96%), seven of seven neurofibromas (100%), three of three spindle cell lipomas (100%), five of five dermatofibrosarcomas (100%), three of three hemangiopericytomas (100%) and two of seven malignant fibrous histiocytomas (29%). To date, most of the pleural and extrapleural cases have not shown aggressive features. We suggest that bcl-2 protein can be used together with CD34 in the diagnosis of solitary fibrous tumor to distinguish this entity from other spindle cell neoplasms.   相似文献   
93.
The mitogen-activated protein (MAP) kinase cascades regulate a variety of cellular activities, including cell growth, proliferation, and apoptosis, and are reported to play a role in the actions of antidepressant treatment. There are a number of different classes of protein phosphatases that could influence the MAP kinase cascade. One of these, the MAP kinase phosphatase (MKP) family, is known to play a key role in dephosphorylation of activated MAP kinase. In the present study, we analyzed the expression of the MKP1, MKP2, and MKP3 isoforms in rat brain after electroconvulsive seizure (ECS), considered the most effective treatment for depression. In situ hybridization analysis demonstrates that ECS differentially regulates the expression of the MKP isoforms. Expression of MKP1 mRNA is robustly increased by acute ECS in the major cell layers of the hippocampus, including the dentate gyrus granule cell layer and the CA1 and CA3 pyramidal cell layers. In contrast, MKP2 is induced mainly in the dentate gyrus and MKP3 is preferentially increased in the CA1 and CA3 cell layers. In the prefrontal cortex, all three MKP isoforms are upregulated by acute ECS administration. Chronic ECS resulted in a similar pattern of induction for each of the MKP subtypes, demonstrating that there is little or no desensitization of the response to repeated ECS. The induction of MKP expression serves as negative feedback control for the MAP kinase cascades. Upregulation of MKP expression could dampen the actions of ECS, indicating that blockade of the MKPs could enhance the actions of antidepressant treatment.  相似文献   
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Granuloma faciale (GF) is a rare chronic dermatosis with still unknown etiopathology, which usually presents a solitary, asymptomatic, smooth reddish‐brown to violaceous plaques or nodules on the face. Various therapeutic approaches, including topical application of corticosteroid or tacrolimus and removal with laser, cryotherapy and surgery have been attempted; however, the outcome has been inconsistent. Herein, we report a case of perinasal nodular GF who repeatedly underwent surgical excisions after the failure of laser treatment. Despite its nomenclature, GF does not manifest granulomatous tissue and the lesion is histopathologically characterized by dense dermal cell infiltration devoid of granulomatous changes and not distinguished by a clear border, which partially explains the difficulty of complete removal in our case. Review of the published work delineated that GF could be largely divided into two clinical subsets: plaque and nodular types. The plaque type GF could be responsive to topical tacrolimus, an approach preferentially adopted nowadays, while nodular type GF was often resistant to topical therapies and required surgical or laser removal. The latter subset often arose around the nose. For this location, surgical excision with sufficient removal margin is sometimes technically difficult when an aesthetically acceptable outcome is expected, explaining the basis for local recurrence. Postoperative recurrence could be observed after years of disease‐free period. These observations indicated that the need for respective treatment strategies for the management of distinctive GF subsets. Of note, a multidisciplinary approach combining radical resection and additional supportive intervention with long‐term follow up may be required for perinasal and nodular GF.  相似文献   
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We describe the successful management of empyema in patients who need fenestration, but whose general condition is compromised by a high count of multi-drug resistant bacteria, deteriorating health, or bronchial fistula. The procedure is performed at the bed side, under local anesthesia. After making an incision in the thoracic wall using electric cautery, fenestration is created by inserting a Lap-Protector so as to widen the intercostal space. Fenestration using a Lap-Protector, which does not require resection of the ribs, is comparable to that obtained using the conventional rib resection method. However, it causes significantly less pain at the incision site, and the gauze can be changed without pain because it is not in direct contact with the fenestration wound. Thus, fenestration using a Lap-Protector is a more convenient and effective technique than conventional fenestration with rib resection for poor risk patients with empyema.  相似文献   
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