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501.
BACKGROUND: Perioperative blood transfusion (BT) appeared to have adverse effects on survival after surgery for malignant tumors while pretransplantation BT suppressed allograft rejection. Interest grew in the effect of BT on postoperative recurrence of Crohn's disease. STUDY DESIGN AND METHODS: To determine the effect of perioperative BT on the recurrence of Crohn's disease after primary surgery, the medical histories of 148 patients with Crohn's disease, 62 males and 86 females (49 nonparous and 37 parous), were reviewed. Eighty-seven patients received perioperative BT. RESULTS: Overall, perioperative BT showed no effect on recurrence. Patients with Crohn's disease limited to the ileum had a better prognosis with regard to recurrence than did patients with Crohn's disease located in the colon or located in both ileum and colon, but the difference was not significant. Perioperative transfusion seemed to protect against recurrent disease after colon resection, which might be explained by the fact that colon resections, which often necessitate perioperative BT, generally result in a shorter bowel segment at risk for recurrent disease. Overall, parous women showed a worse prognosis than nonparous females and men (p = 0.022). Transfusions had a beneficial effect in parous women (p = 0.068) and, after correction for type of operation, this beneficial effect was significant (p = 0.026). After perioperative BT, parous women had a similar prognosis with respect to recurrent Crohn's disease as nonparous females and men. CONCLUSION: Perioperative BT has a beneficial effect on the postoperative recurrence of Crohn's disease in parous women.  相似文献   
502.
Trypanosoma cruzi is genetically classified into at least two major lineages named T. cruzi I (also named Tc I) and T. cruzi II (also named Tc IIb). T. cruzi II is associated with Chagas’ disease in the southern cone of South America, while T. cruzi I is the only one so far identified in chagasic patients of Central America and in the northern part of South America. Herein we identified T. cruzi IIb directly in 9.9% of blood of chronic chagasic patients of Colombia. This finding establishes that in this region, the two T. cruzi lineages are associated with the pathology of Chagas’ disease and have implications in the morbidity and epidemiology of the disease.  相似文献   
503.
HEY1-NCOA2 fusion is most described in mesenchymal chondrosarcoma. This is the first case report of a primary renal spindle cell neoplasm of uncertain malignant potential with a HEY1::NCOA2 fusion identified by Fusionplex RNA-sequencing that is histologically distinct from mesenchymal chondrosarcoma. The neoplasm was identified in a 33-year-old woman without significant past medical history who underwent partial nephrectomy for an incidentally discovered renal mass. The histologic features of the mass included spindle cells with variable cellularity and monotonous bland cytology forming vague fascicles and storiform architecture within a myxoedematous and collagenous stroma with areas of calcification. The morphologic and immunophenotypic features were not specific for any entity but were most similar to low-grade fibromyxoid sarcoma. To date, the patient has not had recurrence, and the malignant potential of the neoplasm is uncertain.  相似文献   
504.
We describe a case of a myoepithelial carcinoma of the superficial parotid gland in a 46-year-old male harboring a novel CTCF::NCOA2 gene fusion. To our knowledge, this novel gene fusion has not been described previously in myoepithelial carcinoma. A 46-year-old male patient presented with a mass involving the superficial left parotid gland with extension into the external auditory canal (EAC) and erosion of the conchal cartilage. Histologically, the neoplasm was composed of uniform spindled, epithelioid/ovoid cells arranged in cords and nests within hyalinized to myxoid stroma. On immunohistochemistry (IHC), the tumor cells demonstrated patchy and variable staining for low molecular weight cytokeratin (CAM5.2), pan-cytokeratin (OSCAR), and S-100. Overall, the morphological and immunohistochemical attributes supported a locally aggressive tumor of myoepithelial differentiation consistent with myoepithelial carcinoma. Molecular analysis using a custom 115-gene gene panel by targeted RNA sequencing, showed an in-frame CTCF::NCOA2 fusion. In addition to reporting this novel fusion in myoepithelial carcinoma, we also discuss relevant differential diagnosis, and provide a brief review of NCOA2 gene function in both normal and neoplastic contexts.  相似文献   
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