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71.
AIM: To study the efficacy and factors associated with a sustained virological response (SVR) in chronic hepatitis C (CHC) relapsing patients.METHODS: Out of 1228 CHC patients treated with pegylated interferon (PEG-IFN) and ribavirin (RBV), 165 (13%) had a relapse. Among these, 62 patients were retreated with PEG-IFN-α2a or -α2b and RBV. Clinical, biological, virological and histological data were collected. Initial doses and treatment modifications were recorded. The efficacy of retreatment and predictive factors for SVR were analyzed.RESULTS: An SVR was achieved in 42% of patients. SVR was higher in young (< 50 years) (61%) than old patients (27%) (P = 0.007), and in genotype 2 or 3 (57%) than in genotype 1 or 4 (28%) patients (P = 0.023). Prolonging therapy for at least 24 wk more than the previous course was associated with higher SVR rates (53% vs 28%, P = 0.04). Also, a better SVR rate was observed with RBV dose/body weight > 15.2 mg/kg per day (70% vs 35%, P = 0.04). In logistic regression, predictors of a response were age (P = 0.018), genotype (P = 0.048) and initial RBV dose/body weight (P = 0.022). None of the patients without a complete early virological response achieved an SVR (negative predictive value = 100%).CONCLUSION: Retreatment with PEG-IFN/RBV is eff-ective in genotype 2 or 3 relapsers, especially in young patients. A high dose of RBV seems to be important for the retreatment response.  相似文献   
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BackgroundExercise training (ET) has been used as a nonpharmacological strategy for treatment of diabetes and myocardial infarction (MI) separately. We evaluated the effects ET on functional and molecular left ventricular (LV) parameters as well as on autonomic function and mortality in diabetics after MI.Methods and ResultsMale Wistar rats were divided into control (C), sedentary-diabetic infarcted (SDI), and trained-diabetic infarcted (TDI) groups. MI was induced after 15 days of streptozotocin-diabetes induction. Seven days after MI, the trained group underwent ET protocol (90 days, 50-70% maximal oxygen consumption-VO2max). LV function was evaluated noninvasively and invasively; baroreflex sensitivity, pulse interval variability, cardiac output, tissue blood flows, VEGF mRNA and protein, HIF1-α mRNA, and Ca2+ handling proteins were measured. MI area was reduced in TDI (21 ± 4%) compared with SDI (38 ± 4%). ET induced improvement in cardiac function, hemodynamics, and tissue blood flows. These changes were probable consequences of a better expression of Ca2+ handling proteins, increased VEGF mRNA and protein expression as well as improvement in autonomic function, that resulted in reduction of mortality in TDI (33%) compared with SDI (68%) animals.ConclusionsET reduced cardiac and peripheral dysfunction and preserved autonomic control in diabetic infarcted rats. Consequently, these changes resulted in improved VO2max and survival after MI.  相似文献   
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Introduction. Hypovolemia from hemorrhage evokes protective compensatory reactions, such as the renin-angiotensin system, which interferes in the clearance function and can lead to ischemia. This study was designed to evaluate the effects of glibenclamide, a K+ATP channel blocker, on renal function and histology in rats in a state of hemorrhagic shock under sevoflurane anesthesia. Material and Methods. Twenty Wistar rats were randomized into two groups of 10 animals each (G1 and G2), only one of which (G2) received intravenous glibenclamide (1 μg.g?1), 60 min before bleeding was begun. Both groups were anesthetized with sevoflurane and kept on spontaneous respiration with oxygen-air, while being bled of 30% of volemia in three stages with 10 min intervals. There was an evaluation of renal function—sodium para-aminohippurate and iothalamate clearances, filtration fraction, renal blood flow, renal vascular resistance—and renal histology. Renal function attributes were evaluated at three moments: M1 and M2, coinciding with the first and third stages of bleeding; and M3, 30 min after M2, when the animals were subjected to bilateral nephrectomy before being sacrificed. Results. Significant differences were found in para-aminohippurate clearance, G1 < G2, and higher renal vascular resistance values were observed in G1. Histological examination showed the greater vulnerability of kidneys exposed to sevoflurane alone (G1) with higher scores of vascular and tubular dilatation. There were vascular congestion and tubular vacuolization only in G1. Necrosis and signs of tubular regeneration did not differ in both groups. Conclusion. Treatment with glibenclamide attenuated acutely the renal histological changes after hemorrhage in rats under sevoflurane anesthesia.  相似文献   
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De novo malignancies are a major cause of late death after liver transplantation. Aim of the present study was to determine whether use of cyclosporine versus tacrolimus affects long‐term tumor incidence considering potential confounders. De novo malignancies in 609 liver transplant recipients at Munich Transplant Centre between 1985 and 2007 were registered. In 1996, the standard immunosuppressive regimen was changed from cyclosporine to tacrolimus. Different effects of those drugs on long‐term tumor incidence were analyzed in multivariate analysis. During 3765 patient years of follow‐up (median 4.78 years), 87 de novo malignancies occurred in 71 patients (mean age 47.5 ± 13.3 years, mean time after liver transplantation 5.7 ± 3.7 years). The cumulative incidence of de novo malignancies was 34.7% for all tumor entities after 15 years as compared to 8.9% for a nontransplanted population. The most frequent tumors observed were nonmelanoma skin cancers (44.83%). Moreover, post‐transplant lymphoid disease, oropharyngeal cancer (n = 6, 6.9%), upper gastrointestinal tract cancer (n = 4, 4.6%), lung cancer (n = 4, 4.6%), gynecological malignancies (n = 4, 4.6%), and kidney cancer (n = 3, 3.45%) were detected. Multivariate analysis revealed recipient age [hazards ratio (HR) 1.06], male gender (HR 1.73), and tacrolimus‐based immunosuppression (HR 2.06) as significant risk factors. Based on those results, a tacrolimus‐based immunosuppression should be discussed especially in older male patients. Whether reducing tacrolimus target levels may reduce the risk for de novo malignancies has yet to be determined in prospective trials.  相似文献   
78.
Adaptive remodelling of the mandibular condyle in response to mandibular advancement is the mechanism exploited by orthodontic forward displacement devices.ObjectiveThis work investigated the expression of collagens, matrix metalloproteinases and vascular endothelial growth factor during this process.DesignTwenty juvenile pigs were randomly divided into two experimental groups, where the treatment group was fitted with mandibular advancement splints, and the control group was not. Changes in the mRNA content of condylar cartilage tissue was then were measured by real-time PCR using specific primers after 4 weeks of treatment.ResultsThe temporal pattern of the expression of Col1 and MMP13 during condylar adaptation coincided with that during natural condylar growth. The amount of the expression of Col10 during condylar adaptation was significantly lower (p < 0.05), whereas the expression of Col2, MMP8 and VEGF was significantly higher compared to natural growth (p < 0.05).ConclusionsIt is suggested that condylar adaptation in growing pigs triggered by mandibular forward positioning results not only from passive adaptation of cartilage, but also involves growth affected processes. Our results showed that mechanical strain produced by mandibular advancement induced remodelling and revascularization in the posteriocranial mandibular condyle. These results are mostly consistent with former published histological and histomorphometrical analyses.  相似文献   
79.
Adult polyglucosan body disease (APBD) is a metabolic disorder usually caused by glycogen branching enzyme (GBE) deficiency. APBD associates progressive walking difficulties, bladder dysfunction and, in about 50% of the cases, cognitive decline. APBD is characterized by a recognizable leukodystrophy on brain MRI. We report here a novel presentation of this disease in a 35-year old woman who presented with an acute deterioration followed by an unexpected recovery. Enzymatic analysis displayed decreased GBE activity in leukocytes. Molecular analyses revealed that only one mutated allele was expressed, bearing a p.Arg515His mutation. This is the first observation reporting acute and reversible neurological symptoms in APBD. These findings emphasize the importance of searching GBE deficiency in patients presenting with a leukodystrophy and acute neurological symptoms mimicking a stroke, in the absence of cardiovascular risk factors.  相似文献   
80.
Multiple sclerosis (MS) is the most common inflammatory demyelinating disease of the central nervous system. Traditionally, demyelinating lesions in the white matter have been regarded as the most important pathological feature in MS, but recent pathological and imaging studies confirmed substantial changes in grey matter and normal-appearing white matter. MS lesions are characterized by inflammation, demyelination, axonal damage and astrogliosis. During early MS lesion formation acute axonal injury is extensive and correlates with inflammation. In addition to focal lesions, diffuse wide-spread changes including neuroaxonal degeneration and compartmentalized inflammation are likely to contribute to increasing disability in progressive MS. Neuromyelitis optica (NMO) is classically characterized by severe transverse myelitis and optic neuritis, but brain lesions are also present in the majority of NMO patients. The discovery of the NMO-specific antibody demonstrated that NMO is a disease entity distinct from MS. This antibody binds to aquaporin-4 expressed in astrocytes and ependymal cells. NMO lesions are characterized by inflammation, demyelination, axonal damage and a marked loss of aquaporin-4. Early NMO lesions demonstrate a pronounced humoral inflammatory response and astrocytic cell death with loss of aquaporin-4, followed by inflammatory demyelination and axonal damage. These recent findings contribute to a better understanding of different mechanisms leading to inflammatory demyelination.  相似文献   
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