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641.
Bini  A; Fenoglio  J Jr; Sobel  J; Owen  J; Fejgl  M; Kaplan  KL 《Blood》1987,69(4):1038-1045
Arterial thrombi and atherosclerotic lesions were analyzed immunochemically and examined histologically. The extent of in vivo proteolytic cleavage of the amino-terminal end of fibrinogen by thrombin and plasmin was determined and quantitated by specific radioimmunoassays. The samples were treated with cyanogen bromide (CNBr), and the total amount of fibrinogen and fibrin-derived protein was determined as NDSK, the NH2-terminal disulfide knot of fibrinogen. Thrombin-releasable fibrinopeptides A and B were used to quantitate fibrinogen and fibrin I. Previous plasmin cleavage of the B beta chain was inferred from the amount of B beta 1-42 and B beta 15-42 in undigested NDSK. The results obtained in both acute and organized thrombi indicate that approximately 60% of the total protein (as determined by amino acid analysis) was fibrinogen-derived and that 70% to 80% of the fibrinogen-derived material was fibrin II. These findings support the hypothesis that fibrin II as distinct from fibrin I is the predominant component in a thrombus. In samples from normal and atherosclerotic aortas, fibrinogen-derived protein comprised less than 10% of the total protein. Samples from grossly normal aortas contained only fibrinogen and fibrin I. Fibrinogen concentration decreased and fibrin II concentration increased with increasing severity of the lesions, suggesting that increased fibrin II formation is associated with progression of atheromas.  相似文献   
642.

Aim

To investigate the osteogenic differentiation of vascular smooth muscle cells (VSMCs) in mice with chronic kidney disease (CKD) and to evaluate the effects of p53 on the osteogenic differentiation of the VSMCs.

Methods

Experimental models of CKD-associated vascular calcification generated by five-sixth (5/6) nephrectomy (Nx) and a high-phosphate (HP) diet were used in p53+/+ and p53–/– mice. Following 5/6 Nx, aortic calcification, markers of osteogenic differentiation, VSMCs and p53 protein in aortic tissues were studied.

Results

Aortic calcification was observed after eight weeks following 5/6 Nx in mice of both genotypes, and expression of the markers of osteogenic differentiation in the VSMCs was increased. These changes were continuously observed up to 12 weeks after 5/6 Nx, and particularly after 5/6 Nx + HP. Compared with p53+/+ mice, aortic calcification in p53–/– mice was more severe (p < 0.001). Expression of the markers of osteogenic differentiation was noticeably increased (p < 0.001), while expression of the marker of VSMCs had decreased (p < 0.001). Statistical analysis demonstrated that the markers of osteogenic differentiation were negatively correlated with p53, and the marker of VSMCs was positively correlated with p53 (p < 0.001).

Conclusion

p53 has the potential to negatively regulate the osteogenic differentiation of VSMCs in CKD mice.  相似文献   
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Mismatch between bone marrow transplant (BMT) patient and donor for an amino acid polymorphism within the adhesion molecule CD31 has recently been reported to increase risk for the development of graft-versus-host disease (GVHD). We further examined this association in a larger series of 301 BMT patients (227 with grade III/IV GVHD and 74 with grade 0 GVHD) and their HLA-identical sibling donors. CD31 genotypes were determined by polymerase chain reaction and restriction endonuclease digestion. The role of mismatch at the CD31 locus in the development of GVHD was assessed by analyzing the extent of CD31 identity and CD31 compatibility among the grade 0 GVHD and grade III/IV GVHD sibling pairs. No significant association between CD31 mismatch and the development of severe GVHD was detected in our overall patient population. Sixty-three percent of grade III/IV GVHD sibling pairs and 69% of grade 0 GVHD sibling pairs had CD31 genotypes that were identical (P = .36, odds ratio = 1.30). In addition, neither the grade 0 GVHD group (P = .10) nor the grade III/IV GVHD group (P = .27) differed significantly from the expected probability of identity between sibling pairs. Mismatch at the CD31 polymorphism between recipients and donors showed no consistent association with the development of GVHD. Current evidence does not support the value of CD31 mismatch in the selection of BMT donors.  相似文献   
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We describe a 15-year-old girl with biopsy-proven morphea who developed progression to systemic disease 2 years after initial presentation. In contrast to other reported patients with localized scleroderma, some of whom have had mild, nonprogressive systemic involvement, this patient developed severe, debilitating disease, with skin tightness, sclerodactyly, esophageal involvement, restrictive pulmonary disease, and myopathy. From the time of her initial evaluation, the patient was positive for antinuclear antibodies (ANA), which were shown to be primarily directed against the Ku antigens. This observation suggests that ANA may be a prognostic indicator for progression to systemic disease.  相似文献   
648.
We report a case of Behcet's syndrome with myositis in a pediatric patient, emphasizing the importance of muscle involvement in the differential diagnosis of calf pain and swelling in Behcet's syndrome. A review of the English-language literature from 1965 to the present suggests that the clinical picture of Behcet's syndrome in children differs from that in adults, in that there is a lower frequency of ocular disease, and unusual manifestations appear to be more common.  相似文献   
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