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Background and Aims: Current histological scoring systems do not subclassify cirrhosis. Computer‐assisted digital image analysis (DIA) of Sirius Red‐stained sections measures fibrosis morphologically producing a fibrosis ratio (collagen proportionate area [CPA]). CPA could have prognostic value within a disease stage, such as cirrhosis. The aim of the present study was to evaluate CPA in patients with recurrent hepatitis C virus (HCV) allograft cirrhosis and assess its relationship with hepatic venous pressure gradient (HVPG). Methods: In 121 consecutively‐transplanted HCV patients with HVPG, measured contemporaneously with transjugular liver biopsies, 65 had Ishak stage 5 or 6 disease (43 with HVPG measurement). Biopsies were stained with Sirius Red for DIA, and the collagen content was expressed as a CPA. In three cases, a tissue for Sirius Red staining was not obtained, and the patients were excluded. Results: Sixty‐two patients were analyzed. The median HVPG was 8 mmHg (interquartile range [IQR]: 5–10). Portal hypertension (HVPG ≥ 6 < 10 mmHg) was present in 30 (69.8%), and HVPG ≥ 10 mmHg in 13 (30.2%). The median CPA was 16% (IQR 10.75–23.25). Median Child–Pugh score and HVPG were not significantly different between Ishak fibrosis stage 5 or 6, whereas CPA was statistically different: 13% in stage 5 (IQR 8.3–12.4) versus 23% in stage 6 (IQR 17–33.7, P < 0.001). In the multivariate analysis, CPA was the only variable significantly associated with clinically‐significant portal hypertension (HVPG ≥ 10 mmHg, odds ratio: 1.085, confidence interval: 1.004–1.172, P = 0.040). A CPA of 14% was the best cut‐off value for clinically‐significant portal hypertension (CSPH) and liver decompensation, which occurred in 24 patients. Event‐free survival was significantly shorter in patients with CSPH or with a CPA value ≥ 14%, or with a combination of both. Conclusion: In Ishak stages 5 and 6, CPA correlated with HVPG, but had a wider range of values, suggesting a greater sensitivity for distinguishing “early” from “late” severe fibrosis/cirrhosis. CPA was a unique, independent predictor of HVPG ≥ 10 mmHg. CPA can be used to subclassify cirrhosis and for prognostic stratification.  相似文献   
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Recombinant parathyroid hormone (rPTH) therapy has been evaluated for skeletal repair in animal studies and clinical trials based on its known anabolic effects, but its effects on angiogenesis and fibrosis remain poorly understood. We examined the effects of rPTH therapy on blood vessel formation and osseous integration in a murine femoral allograft model, which caused a significant increase in small vessel numbers, and decreased large vessel formation (p < 0.05). Histology showed that rPTH also reduced fibrosis around the allografts to similar levels observed in live autografts, and decreased mast cells at the graft‐host junction. Similar effects on vasculogenesis and fibrosis were observed in femoral allografts from Col1caPTHR transgenic mice. Gene expression profiling revealed rPTH‐induced angiopoietin‐1 (8‐fold), while decreasing angiopoietin‐2 (70‐fold) at day 7 of allograft healing. Finally, we show anti‐angiopoietin‐2 peptibody (L1‐10) treatment mimics rPTH effects on angiogenesis and fibrosis. Collectively, these findings show that intermittent rPTH treatment enhances structural allograft healing by two processes: (1) anabolic effects on new bone formation via small vessel angiogenesis, and (2) inhibition of angiopoietin‐2–mediated arteriogenesis. The latter effect may function as a vascular sieve to limit mast cell access to the site of tissue repair, which decreases fibrosis around and between the fractured ends of bone. Thus, rPTH therapy may be generalizable to all forms of tissue repair that suffer from limited biointegration and excessive fibrosis. © 2013 American Society for Bone and Mineral Research.  相似文献   
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Choroid plexus papillomas are rare neoplasms that arise from choroid plexus epithelium. The World Health Organization classification describes three histological grades. Grade I is choroid plexus papilloma, grade II is atypical choroid plexus papilloma and grade III is choroid plexus carcinoma. Progression between grades is rare but documented. We present two adult cases, a 53-year-old female and a 70-year-old male, who demonstrated clear interval histological progression from grade I choroid plexus papilloma to higher grades.  相似文献   
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Eosinophilic angiocentric fibrosis and extrafacial granuloma faciale   总被引:1,自引:0,他引:1  
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ObjectiveTo identify predictors of recurrence-free survival (RFS) based on the clinicopathological features of patients with upper tract urothelial carcinoma (UTUC) who have undergone radical nephroureterectomy (RNU) with bladder cuff resection.Materials and methodsWe retrospectively reviewed the records of patients from October 1998 to July 2012 at our tertiary institution and identified 120 patients with sufficient data who underwent RNU for UTUC. We recorded various clinical and histopathological parameters as potential predictors of outcome. Recurrence was defined as any occurrence of urothelial carcinoma after RNU either intravesically, local/regionally, or at distant sites. Univariate, multivariate, and RFS analyses were conducted using the Cox regression and Kaplan-Meier methods.ResultsThe median age of our cohort was 71 years (interquartile range: 64–78). Median RNU-specimen tumor size was 3.0 cm (interquartile range: 2.0–5.0 cm). Fifty-four patients (45%) had a tumor<3.0 cm and 66 (55%) had a tumor≥3.0 cm. Eighty patients (66.7%) had organ-confined UTUC (≤pT2) and 40 (33.3%) had non–organ-confined UTUC (≥pT3). Sixty-five patients (54.2%) experienced at least 1 recurrence. Forty-three patients (35.8%) had at least 1 episode of intravesical recurrence and 28 (23.3%) had distant recurrence. A multivariate analysis revealed non–organ-confined disease (hazard ratio [HR] = 3.62, P<0.001), tumor diameter≥3 cm (HR = 1.97, P = 0.011), and male gender (HR = 1.81, P = 0.047) to be significant independent predictors of disease recurrence. The 5-year RFS rate was 46.9% and 25.8% for patients with tumor size<3 and≥3 cm, respectively.ConclusionsFollowing RNU, the incidence of recurrence remains high among patients with UTUC. In our cohort of patients, tumor diameter≥3.0 cm, non–organ-confined UTUC, and male gender constitute important risk factors for poor RFS outcomes following RNU. These patients require diligent postoperative surveillance and may potentially benefit from perioperative systemic therapy.  相似文献   
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