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51.
BACKGROUND: The predictive value of clinical and renal histological features for renal outcome in patients with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis was investigated in a prospective analysis of 96 patients with ANCA-associated vasculitis, and moderate renal involvement (creatinine <500 micromol/L). METHODS: The extent of 39 histological features in 96 biopsies (performed at entry in a clinical trial) was scored by two independent observers, according to a standardized protocol. Age, gender, diagnosis, glomerular filtration rate at entry (GFR0), ANCA-specificity, proteinuria, and treatment of these 96 patients were also taken into account. Treatment was standardized and started after the biopsy was performed. End-points included renal function at 18 months (GFR18), GFR18 corrected for GFR0 (CORGFR18), and the occurrence of relapse or death. RESULTS: Parameters that most strongly correlated with GFR18 were GFR0 (r = 0.67), interstitial fibrosis (r = -0.45), glomerulosclerosis (r = -0.37), and tubular atrophy (r = -0.36). Parameters that most strongly correlated with CORGFR18 were segmental (r = 0.45) and cellular (r = 0.30) crescents, and fibrinoid necrosis (r = 0.46). None of the clinical and histological features predicted the occurrence of relapse or death. By applying a stepwise linear multiple regression analysis, we designed a formula for the estimation of renal function at 18 months: GFR18 (mL/min) = 17 + 0.71 x GFR0 (mL/min) + 0.34 x fibrinoid necrosis (%) + 0.33 x segmental crescents (%), (r2 = 0.60; standard deviation = 19 mL/min). Our results were independent of diagnosis, ANCA-specificity, and treatment limb. CONCLUSIONS: These data suggest that in ANCA-associated glomerulonephritis, GFR0 and predominantly chronic renal lesions are potent predictors of GFR18. Active lesions are associated with renal function recovery and may be reversible. The formula for the estimation of GFR18 shows that a combination of GFR0 and renal histology is a better predictor for GFR18 than GFR0 only.  相似文献   
52.
BACKGROUND: Historically the Fontan operation in patients with single ventricle heterotaxy syndrome and atrial isomerism has been associated with high mortality. We studied whether recent modifications of the surgical technique have improved outcome. METHODS: A retrospective review of 135 patients with heterotaxy syndrome who underwent a Fontan operation between 1981 and 2000 was performed. RESULTS: There were 93 patients with right isomerism and 42 with left isomerism. Anomalies of venous return included 25 patients with extracardiac pulmonary venous connection (19%) and 37 patients with an interrupted inferior vena cava (27%). Thirty-six patients (27%) had at least moderate atrioventricular valve regurgitation. The type of Fontan procedure included 17 patients with an atriopulmonary Fontan connection, 67 with a lateral tunnel modification, 19 with an intraatrial tube graft, 25 with an extracardiac tubegraft, and 7 with an intra-extra atrial tube graft. A fenestration was placed in 93 patients (78%). Early mortality was 19% before 1991, 3% since 1991, and no patient has died early since 1993. Ten-year survivals were 70% for Fontan operations before 1990 and 93% for Fontan operations after 1990. Thirty-two patients (23%) had prolonged pleural effusions. Risk factors for death included anomalous pulmonary venous connection (p = 0.02) and higher preoperative pulmonary vascular resistance (p = 0.002). Sixty-two patients (47%) had some form of early postoperative arrhythmia. At 10 years, freedom from late bradyarrhythmia and late tachyarrhythmia were 78% and 70%, respectively. Preoperative arrhythmias, older age at operation, and anatomic features were each independent predictors of late arrhythmia. CONCLUSIONS: The Fontan operation can now be performed in patients with heterotaxy syndrome with excellent survival. However, morbidity in terms of postoperative arrhythmias and prolonged pleural effusions remains significant. Fontan staging, appropriate choice of Fontan modification, aggressive treatment of concomitant malformations, and use of a baffle fenestration contribute to improved outcome.  相似文献   
53.
(n-3) Fatty acids may reduce the risk of sudden death by preventing life-threatening cardiac arrhythmia. A standard electrocardiogram (ECG) may be used to detect clues as to the mechanism by which (n-3) fatty acids affect the electrophysiology of the heart. An earlier study showed that (n-3) fatty acids decreased the duration of the heart-rate corrected QT interval (QTc) in dogs. However, effects of (n-3) fatty acids on the standard ECG of humans have not been reported. Therefore, we investigated the effect of (n-3) fatty acids on QTc, QRS duration, apex-to-end-T duration, T-loop morphology and spatial QRS-T angle in apparently healthy men and women aged 50 to 70 y. Subjects (n = 42/group) received either capsules providing 1.5 g (n-3) fatty acids daily or placebo for 12 wk. ECG were recorded before and after intervention. None of the ECG characteristics were affected by (n-3) fatty acids. The QTc decreased by 0.8 ms or 0.2% (95% confidence interval, -6.1 to 4.4 ms) in subjects that consumed (n-3) fatty acids compared with the placebo group. These results do not support the hypothesis that (n-3) fatty acids prevent arrhythmia through electrophysiologic effects on heart cell membranes. However, an effect on the ECG in more susceptible populations can not be excluded.  相似文献   
54.
We analysed whether the factor V Leiden mutation--the most common hereditary predisposing factor for venous thrombosis--is associated with early and long-term graft dysfunction after kidney transplantation in 394 Caucasian kidney transplant recipients. The presence of factor V Leiden mutation was identified by allele specific PCR. The prevalence of the factor V Leiden mutation was compared to 32216 unselected neonates. The prevalence of the factor V Leiden mutation (GA genotype) was similar in 394 kidney transplant recipients and 32216 neonates. The frequency of known factors predicting long-term graft function were similar in patients with the GA genotype and with the normal factor V gene (GG genotype). The GA genotype was associated with the occurrence of no primary graft function (risk: 2.87: 95% confidence interval: 1.01-8.26; p < 0.05), the number of dialysis after transplantation in patients with no primary graft function until graft function (7.5 +/- 2.06 dialysis in GA patients; 4.2 +/- 0.36 dialyses in GG patients; p < 0.05), and the risk for at least one acute rejection episode (risk: 3.83; 95% confidence interval: 1.38-10.59; p < 0.02). The slope of l/creatinine per year was significantly lower in patients with the GA genotype (GA patients: -0.0204 +/- 0.008 dl/mg per year; GG patients: 0.0104 +/- 0.004 dl/mg per year; p < 0.02). The annual enhancement of the daily protein excretion rate was elevated in patients with the GA genotype (GA patients: 38.5 +/- 16.6 mg/24 h per year; GG patients: 4.9 +/- 4.4 mg/24 h per year; p < 0.02). Our study showed that the factor V Leiden mutation is associated with the occurrence of delayed graft function, acute rejection episodes and chronic graft dysfunction after kidney transplantation.  相似文献   
55.
Pet birds and risk of lung cancer in North-Western Germany   总被引:35,自引:0,他引:35  
The relationship between non-small cell lung cancer and platelet counts, serum levels of vascular endothelial growth factor (VEGF) and endostatin, is unclear. Platelet counts and serum VEGF and endostatin levels were measured preoperatively in 99 patients with non-small cell lung cancer, and the relationship between these factors and clinicopathological features, including prognosis, was examined. Mean serum VEGF level was slightly higher in patients than in healthy subjects (P=0.23). Mean serum endostatin level was 42.4+/-40.4 ng/ml in patients compared to 16.3+/-10.3 ng/ml in healthy subjects (P=0.0003). Serum endostatin levels were significantly higher in patients with involvement greater than T2 or stage IB, compared to other patients. Platelet count and serum endostatin level greater than the median were associated with poor prognosis. Our results suggested that platelet count and serum endostatin level may be useful markers for non-small cell lung cancer.  相似文献   
56.
Assessment of tumour cell proliferation in glioblastoma (GB) has been a topic of considerable research interest over the past decade. However, the correlation of tumour proliferation and patient outcome has yielded controversial results. In this study, we examined immunohistochemically, using paraffin-embedded tissue, the expression of the proliferation-related markers DNA topoisomerase IIalpha (TIIalpha) and Ki-67 antigen in a cohort of 114 GB patients treated consecutively with surgery and radiochemotherapy, and correlated the expression with patient outcome. The TIIalpha labelling index (LI) ranged between 5.2 and 87.2% (median: 25.6%). Survival analysis disclosed an association between high TIIalpha expression levels and prolonged survival (P=0.040, log-rank test). TIIalpha expression correlates closely with Ki-67 labelling index (R=0.927, P<0.001), which itself is predictive of patient survival (P=0.044). However, in multivariate analysis, only the Karnofsky performance status remained predictive of patient survival. We conclude that high expression of TIIalpha and Ki-67 appears to be associated with a prolonged survival in our cohort of GB patients.  相似文献   
57.
For the investigation of the skin irritancy potential of chemicals in an in vitro model it is necessary to have sensitive endpoints that predict the effects of those compounds on native human skin. Recently, we have identified that 27-kDa heat shock protein (HSP27) can serve as a sensitive marker of skin irritation, as exposure of human skin to sodium lauryl sulfate (SLS) both in vitro and in vivo induced relocalization of HSP27 from the cytoplasm to the cell nucleus. The aim of the present study was to determine whether nuclear localization of HSP27 could be used as a parameter for evaluation of potential skin irritants in screening assays in vitro. For this purpose, human skin equivalent consisting of epidermis reconstructed on de-epidermized dermis was exposed to SLS or UV light. Stress-induced nuclear relocalization of HSP27 was observed in excised skin exposed to SLS or UV light and in reconstructed epidermis only when the latter was generated in the absence of vitamin C. The omission of vitamin C results in an impaired barrier function. In the presence of vitamin C, however, the barrier function was comparable with excised skin, suggesting that vitamin C may control the response to stress in the reconstructed epidermis. Besides the presence of vitamin C, the response of skin equivalents may strongly depend on other conditions under which they are generated, because the stress-induced HSP27 relocalization was not detected in the commercially available epidermal kit EpiDerm. The results of the present study show that HSP27 nuclear staining can serve as a sensitive marker for skin irritation or cellular stress in excised skin as well as in certain well-characterized human skin equivalents in vitro.  相似文献   
58.
59.
To test the significance of human papillomavirus (HPV) type 16 and HPV16 E6 variants as risk factors for viral persistence and progression to high-grade lesion, we did a nested case-control study within a cohort study of >15,000 Caucasian French women. Three groups infected with high-risk HPV were compared: (a) women with cleared infection (controls, n = 201), (b) women with persistent infection (cases, n = 87), and (c) women who progressed into high-grade lesion (cases, n = 58). Women with persistent HPV infection and those that progressed into high-grade lesions were likelier to harbor HPV16 than other high-risk HPV types [odds ratio (OR), 2.4; 95% confidence interval (95% CI), 1.3-4.3 and OR, 4.2; 95% CI, 2.2-8.1, respectively]. Notably, especially elevated ORs of persistence (3.0; 95% CI, 1.4-6.7) and progression (6.2; 95% CI, 2.7-14.3) were found among women who harbored the HPV16 350G variant. Thus, HPV type and HPV16 variant seem to be risk factors for viral persistence and progression of infections into high-grade cervical lesions.  相似文献   
60.
Clinical features of the spinal form of multiple sclerosis   总被引:4,自引:0,他引:4  
Out of a data pool of 1271 patients with Multiple Sclerosis (MS) a total of 109 cases are selected having a sole spinal symptomatology throughout the course of the disease. This group differs in three particular features from the non-spinal forms of MS: In this group there is a higher percentage of females, the age at onset of the disease is higher, and the course of the disease is more often chronic progressive from the beginning. After the mean duration of 11 years, the spinal and the non-spinal cases show the same grade of disability. The ability to work is slightly better for spinal cases; office workers are able to keep their jobs longer after the onset to the disease than patients with any other occupation. The spinal form of MS is discussed in respect to its relationship to the classical form of MS and as a differential diagnosis to other spinal processes.  相似文献   
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