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31.
BACKGROUND & AIMS: Idiopathic eosinophilic esophagitis is an underdiagnosed disease with typical endoscopic findings, which have not been well described. METHODS: Charts and pathology reports at two tertiary care centers from June 1993 to April 2002 were reviewed to describe the endoscopic findings of this disease and to correlate them with clinical characteristics. Eight patients were identified as having eosinophilic esophagitis based on clinical symptoms and pathology reports. RESULTS: Soft and subtle ring(s) in the esophagus were found in 7 of 8 patients. In 3 of 8 patients, the esophagus appeared rigid. Mucosal rents occurred with simple passage of the endoscope in 5 of 8 patients. One patient developed a perforation after simple passage of the endoscope. Endoscopic findings can be normal or very subtle in these patients, and the findings can easily be missed during endoscopy. Tearing of the esophagus can occur with simple passage of the endoscope or biopsy even in the absence of overt rings. A minimum of 8 weeks of medical therapy (proton pump inhibitor, histamine antagonists, immunosuppressants) should be undertaken before considering dilation because of the high risk involved with the procedure and the good response to medical therapy. CONCLUSIONS: We recommend considering dilation only in patients with eosinophilic esophagitis who do not respond to medical therapy and have rings that appear to be obstructing the lumen.  相似文献   
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OBJECTIVE: Although the platelet destruction shows a primary role in the thrombocytopenia of idiopathic thrombocytopenic purpura (ITP), it has been demonstrated that impaired platelet production may also contribute to the severity of thrombocytopenia in ITP. The present study examined megakaryocyte apoptosis in bone marrow aspirates of children with acute and chronic ITP and investigated the role of megakaryocyte apoptosis in ITP pathophysiology. METHODS: Thirteen children diagnosed with acute ITP and eight children diagnosed with chronic ITP comprised the study group. Ten children, who were hospitalized for scoliosis operation but healthy otherwise, comprised the control group. In all children, megakaryocytes were isolated from the same amount of bone marrow aspirate samples using MACS CD61 MicroBeads (Miltenyl Biotec, Auburn, CA, USA). Megakaryocyte apoptosis was studied with transferase-mediated d-UTP-bitin nick end-labeling method. RESULTS: Isolated megakaryocyte counts did not differ significantly between acute ITP, chronic ITP and control groups. The percentage of apoptotic megakaryocytes did not differ significantly between acute ITP group and control group and between chronic ITP group and control group. The percentage of apoptotic megakaryocytes in patients with chronic ITP was significantly lower than the patients with acute ITP. There was no correlation between the percentage of apoptotic megakaryocytes and platelet counts of the cases. CONCLUSIONS: Increased megakaryocytic apoptosis does not play a role in the pathogenesis of dysmegakaryopoiesis and impaired platelet production in children with ITP. Decreased megakaryocyte apoptosis in cases with chronic ITP may be due to suppression of megakaryocyte maturation, as the terminal phase of the megakaryocyte lifespan is characterized by the onset of apoptosis.  相似文献   
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European Journal of Clinical Microbiology & Infectious Diseases - Since its emergence in December 2019, SARS-CoV-2 is causing one of the most devastating pandemics in human history. Currently,...  相似文献   
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The estimation of survival of myelodysplastic syndromes (MDS) and risk of progression into acute myeloid leukaemia is challenging due to the heterogeneous clinical course. The most widely used prognostic scoring system (International Prognostic Scoring System [IPSS]) was recently revised (IPSS‐R). The aim of this study was to investigate the prognostic relevance of flow cytometry (FC) in the context of the IPSS‐R. Bone marrow aspirates were analysed by FC in 159 patients with MDS. A flow score was calculated by applying the flow cytometric scoring system (FCSS). Patients were assigned to IPSS and IPSS‐R risk groups. The FCSS correlated with the World Health Organization classification, IPSS and IPSS‐R risk groups. Mild flow cytometric abnormalities were associated with significantly better overall survival (OS) and lower risk of disease evolution. The presence of aberrant myeloid progenitors was associated with transfusion dependency and disease progression. Most importantly, the FCSS identified prognostic subgroups within the IPSS‐R cytogenetic good risk and low risk group. Flow cytometric analysis in patients with MDS provides additional prognostic information and is complementary to the IPSS‐R. The addition of a flow cytometric score next to the clinical parameters within the IPSS‐R is a further refinement of prognostication of patients with MDS.  相似文献   
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Elucidation of the molecular mechanisms of leukemogenesis is important for a better understanding of the prognosis of acute lymphoblastic leukemia (ALL). Studies have shown that the expression of upregulated gene 4 (URG4), which promotes cell growth and survival, is increased in different types of carcinomas including hepatocellular carcinoma, gastric cancer and osteosarcoma. Similarly, higher expression of URG4 and cyclin D1 gene might promote proliferation of the blast cells by causing escape from the G1 checkpoint and entry into the S phase. This study reports the high expression level of URG4 in 2 high-risk ALL patients for the first time in the literature. In conclusion, the higher expression of URG4 in our 2 patients suggests that URG4 might be involved in leukemogenesis. Future studies with a large number of high-risk ALL patients and cell culture studies are needed to demonstrate the exact role of URG4 in leukemogenesis.  相似文献   
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OBJECTIVES:

In addition to its roles in the stimulation of growth hormone secretion and the regulation of appetite and metabolism, ghrelin exerts immunomodulatory, anti-inflammatory and antioxidant actions in several organ systems. In this study, we investigated the effects of ghrelin on the healing of experimental colonic anastomoses.

METHODS:

Wistar rats were randomly divided into two groups (n = 10 in each). A segment of colon was excised, and an end-to-end anastomosis was performed in the distal colon. The Ghrelin Group received 10 ng/kg/day IP ghrelin for seven days postoperatively, whereas the Control Group received an identical volume of saline. On the seventh postoperative day, the anastomotic bursting pressures and hydroxyproline levels were measured, and adhesion formation around the anastomoses was examined. Histopathological analyses were performed to evaluate inflammatory cell infiltration, fibroblast infiltration, collagen density and neovascularization.

RESULTS:

In the Ghrelin Group, the bursting pressure and hydroxyproline levels were significantly higher than in the Control Group. The adhesion formation scores were lower in the Ghrelin Group than in the Control Group. Although the inflammatory cell infiltration was diminished in the Ghrelin Group, the degrees of fibroblast infiltration, collagen density and neovascularization were not significantly different between the groups.

CONCLUSION:

Our results indicate that ghrelin improves the healing of colonic anastomoses in rats.  相似文献   
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