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11.
Vascular closure devices are used to provide quick hemostasis and early ambulation after percutaneous interventions. The Angio-Seal (AS) vascular closure device forms a mechanical seal by closing the puncture site located between a bioabsorbable anchor within the lumen and a collagen sponge on the adventitia. Although morbidities associated with AS are reportedly infrequent, even the slightest inaccuracy in device implantation may result in displacement of these device components, leading to sudden and severe complications. We report the surgical treatment of complications associated with the use of AS in four patients, including acute limb ischemia, pseudoaneurysm formation, significant hemorrhage, and hypovolemic shock. A common factor in all these cases was that the components of the AS device were displaced from their original site of implantation, stressing the importance of proper device placement. All patients underwent successful surgical vascular repair. Our report highlights the need for exercising extreme care during device implantation, and also the requirement for vigilant inspection for any associated vascular complications commencing immediately after device implantation. It is vital that these device components are actively looked for and removed during surgical exploration so as to prevent future complications.  相似文献   
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While most BK virus infections are asymptomatic, immunosuppression has been associated with BK virus reactivation and impaired graft function or ureteric ulceration in renal transplant patients and hemorrhagic cystitis in bone marrow transplant patients. Oncogenicity is also postulated and this is the first report of a child with a carcinoma of the donor renal pelvis following BK virus allograft nephropathy. Removal of the primary tumor and cessation of immunosuppression led to regression of secondary tumors and a return to health.  相似文献   
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Objective: The influence of left ventricular (LV) dysfunction on survival of patients with severe aortic stenosis is poorly characterized. Few data are available about preoperative predictors of cardiac mortality and LV function recovery after aortic valve replacement of such patients. The aim of our study was to examine the outcome and the preoperative predictors of postoperative cardiac death and of LV function recovery in these patients. Methods: We evaluated 85 consecutive patients with severe aortic stenosis (aortic valve area <1 cm2) and severe depression of LV ejection fraction (EF) <35% at cardiac catheterization. Among them, 52 underwent aortic valve replacement and they were compared to patients who were not operated on. All patients had a mean clinical follow-up of 53 months and 94% of them had a mean echocardiographic follow-up of 14 months after aortic valve replacement. Results: The mean baseline characteristics included: LVEF 28±6%, peak-to-peak transvalvular gradient 51±29 mmHg, aortic valve area 0.63±0.25 cm2. Thirty-three patients did not undergo aortic valve replacement: 32 of them died within 3 years. Fifty-two patients underwent aortic valve replacement and 16 had a concomitant coronary bypass surgery. In-hospital mortality was 8%. Postoperative NYHA functional class changed from 2.84±0.67 to 1.43±0.44 (P<0.001) and LVEF from 29±6% to 43±10% (P<0.001). At follow-up 10 patients died of heart disease. By multivariate analysis, preoperative LV end-systolic volume index (ESVI) was the only covariate of cardiac death (LVESVI/10 ml/m2, OR 1.3, CI 1.1–1.8, P<0.028). By using a receiver operating characteristic curve, LVESVI≤90 ml/m2 was the best cut-off value (sensitivity and specificity 78%) to fit with a better survival (93% vs. 63%, P<0.01) and with LVEF recovery after aortic valve replacement (EF improved by 15±10% vs. 8±5%, P<0.001). Conclusions: Despite LV dysfunction, aortic valve replacement appears to change drastically the natural history of severe aortic stenosis. Preoperative LV levels predict different postoperative survival rate and LVEF recovery.  相似文献   
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Diabetes mellitus is a common systemic disease that has been associated with poor fracture healing outcomes. The mechanism through which diabetes impairs bone regeneration is unknown. One possible mechanism may be related to either decreased or uncoordinated release of local growth factors at the fracture site. Indeed, previous studies have found reduced platelet‐derived growth factor (PDGF) levels in the fracture callus of diabetic rats, suggesting that local application of PDGF may overcome the negative effects of diabetes and promote fracture healing. To test this hypothesis, low (22 µg) and high (75 ug) doses of recombinant human PDGF‐BB (rhPDGF‐BB) were applied directly to femur fracture sites in BB Wistar diabetic rats that were then compared to untreated or vehicle‐treated animals. rhPDGF‐BB treatment significantly increased early callus cell proliferation compared to that in control specimens. Low dose rhPDGF‐BB treatment significantly increased callus peak torque values (p < 0.05) at 8 weeks after fracture as compared to controls. High dose rhPDGF‐BB treatment increased callus bone area at 12 weeks postfracture. These data indicate that rhPDGF‐BB treatment ameliorates the effects of diabetes on fracture healing by promoting early cellular proliferation that ultimately leads to more bone formation. Local application of rhPDGF‐BB may be a new therapeutic approach to treat diabetes‐impaired fracture healing. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 1074–1081, 2009  相似文献   
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Objectives

In numerous malignancies, angiogenin (ANG) and Maspin are important proangiogenic and antiangiogenic regulators, respectively. The aim of this study was to identify potential relationships between the biological roles of these two proteins in laryngeal squamous cell carcinoma (LSCC).

Methods

Immunohistochemical staining for ANG and Maspin was performed on specimens from 76 consecutive LSCC patients treated with surgery alone, considering the subcellular pattern of Maspin expression. Univariate and multivariate statistical models were used for prognostic purposes.

Results

On univariate analysis, a different level of ANG expression was seen for patients stratified by subcellular Maspin expression pattern: the mean ANG expression was higher in cases with a nonnuclear MASPIN expression than in those with a nuclear pattern (P=0.002). Disease-free survival (DFS; in months) differed significantly when patients were stratified by N stage (P=0.01). Patients whose Maspin expression was nonnuclear (i.e., it was cytoplasmic or there was none) had a significantly higher recurrence rate (P<0.001), and shorter DFS (P=0.01) than those with a nuclear Maspin pattern. The mean ANG expression was significantly higher in cases with loco-regional recurrent disease (P=0.007); and patients with an ANG expression ≥5.0% had a significantly shorter DFS than those with an ANG expression <5.0% (P=0.007). On multivariate analysis, ANG expression ≥5.0% was a significant, independent, negative prognostic factor in terms of DFS (P=0.041).

Conclusion

Our results support the hypothesis that a higher ANG expression is associated with a nonnuclear Maspin expression pattern in patients with LSCC. Further studies are needed to clarify the relationship between the ANG and Maspin pathways, and their potential diagnostic and therapeutic role in LSCC.  相似文献   
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Clinical and Experimental Medicine - Human Cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) are endowed with the ability of establishing lifelong latency in human hosts and reactivating in...  相似文献   
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