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AIM: To evaluate outcomes of radiofrequency ablation(RFA) therapy for early hepatocellular carcinoma(HCC) and identify survival- and recurrence-related factors. METHODS: Consecutive patients diagnosed with early HCC by computed tomography(CT) or magnetic resonance imaging(MRI)(single nodule of ≤ 5 cm, or multi-(up to 3) nodules of ≤ 3 cm each) and who underwent RFA treatment with curative intent between January 2010 and August 2011 at the Instituto do Cancer do Estado de S o Paulo, Brazil were enrolled in the study. RFA of the liver tumors(with 1.0 cm ablative margin) was carried out under CT-fluoro scan and ultrasonic image guidance of the percutaneous ablation probes. Procedure-related complications were recorded. At 1-mo post-RFA and 3-mo intervals thereafter, CT and MRI were performed to assess outcomes of complete response(absence of enhancing tissue at the tumor site) or incomplete response(enhancing tissue remaining at the tumor site). Overall survival and diseasefree survival rates were estimated by the Kaplan-Meier method and compared by the log rank test or simple Cox regression. The effect of risk factors on survival was assessed by the Cox proportional hazard model. RESULTS: A total of 38 RFA sessions were performed during the study period on 34 patients(age in years: mean, 63 and range, 49-84). The mean follow-up time was 22 mo(range, 1-33). The study population showed predominance of male sex(76%), less severe liver disease(Child-Pugh A, n = 26; Child-Pugh B, n = 8), and single tumor(65%). The maximum tumor diameters ranged from 10 to 50 mm(median, 26 mm). The initial(immediately post-procedure) rate of RFAinduced complete tumor necrosis was 90%. The probability of achieving complete response was significantly greater in patients with a single nodule(vs patients with multi-nodules, P = 0.04). Two patients experienced major complications, including acute pulmonary edema(resolved with intervention) and intestinal perforation(led to death). The 1- and 2-year overall survival rates were 82% and 71%, respectively. Sex, tumor size, initial response, and recurrence status influenced survival, but did not reach the threshold of statistical significance. Child-Pugh class and the model for end-stage liver disease score were identified as predictors of survival by simple Cox regression, but only Child-Pugh class showed a statistically significant association to survival in multiple Cox regression analysis(HR = 15; 95%CI: 3-76 mo; P = 0.001). The 1-and 2-year cumulative disease-free survival rates were 65% and 36%, respectively. CONCLUSION: RFA is an effective therapy for local tumor control of early HCC, and patients with preserved liver function are the best candidates.  相似文献   
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To evaluate risk factors for colonization or infection due to multidrug-resistant Pseudomonas aeruginosa (MDRPa) carrying the bla(SPM) gene (SPM-MRDPa) among hospitalized patients, we undertook a case control study at a 480-bed, tertiary-care university hospital. Two different case definitions were used. In the first definition, a case patient (SPM case patient) was defined as a patient who had at least one isolate of SPM-MDRPa (14 patients). In the second, a case patient (non-SPM case patient) was defined as a patient who had at least one isolate of non-SPM-MDRPa (18 patients). For each case patient, we selected two controls, defined as a patient colonized and/or infected by a non-MDRPa isolate during the same study period and with the closest duration of hospitalization until the isolation of P. aeruginosa as cases. The use of quinolones was the single independent predictor of colonization and/or infection by bla(SPM) MDRPa (odds ratio [OR] = 14.70, 95% confidence interval [95% CI] = 1.70 to 127.34, P = 0.01), whereas the use of cefepime was the single predictor of colonization and/or infection by non-bla(SPM) MDRPa (OR = 8.50, 95% CI = 1.51 to 47.96, P = 0.01). The main risk factor for MDRPa was a history of antibiotics usage. Stratification of risk factor analysis by a precise mechanism of resistance led us to identify a specific antibiotic, a quinolone, as a predictor for SPM-MDRPa.  相似文献   
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The incorporation of the curcumin into poly(lactic-co-glycolic)acid (PLGA) nanospheres by the nanoprecipitation technique, the characterization of the nanoparticles and the schistosomicidal activity of the curcumin-loaded into PLGA nanospheres were reported. The incorporation process occurred with high efficiency and the images of field-emission scanning electron microscopy (FESEM) revealed the production of spherically shaped particles. According to the dynamic light scattering measurements, the particles are nanometric and monodisperse. The curcumin-loaded PLGA nanoparticles (50 and 100 μM) caused the death of all worms and a separation between 50% and 100% of Schistosoma mansoni couples at concentrations from 30 μM. Moreover, the curcumin-loaded PLGA nanoparticles also decreased the motor activity and caused partial alterations in the tegument of adult worms. This study marks the first time that schistosomicidal activity has been reported for curcumin-loaded PLGA nanoparticles.  相似文献   
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Myopericytoma is a recently described hemangiopericytoma-like neoplasm with myoid differentiation. These tumors are typically located in the subcutaneous and soft tissues of the extremities. The authors report a rare pleural-based pulmonary myopericytoma in a 58-year-old woman. The lesion was grossly homogeneous and well circumscribed. Microscopically, it was composed of densely packed spindle cells organized as whorls and short interlacing fascicles with a concentric perivascular distribution. Immunohistochemical reactions were positive for vimentin, smooth muscle actin (SMA), muscle-specific actin, and Bcl-2 and negative for desmin, h-caldesmon, cytokeratin, and CD34. Atypically, increased mitotic activity was noted, but no other malignant features were identified. The differential diagnoses are discussed with specific emphasis on solitary fibrous tumor of the pleura, which is the most common benign pleural-based spindle cell neoplasm and may be a diagnostic pitfall with potentially harmful consequences.  相似文献   
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The aim of this study was to evaluate the histopathologic features and the expression of angiogenesis-related markers in primary tumors and metastatic lymph nodes of oral squamous cell carcinomas (SCCs) with multiple lymph node involvement in comparison with oral SCCs without nodal metastasis. The protein levels of the angiogenesis inhibitor endostatin, as well as those of the related molecules collagen XVIII, collagen-binding protein (CBP) 2/heat shock protein (HSP) 47, and cathepsin L, were evaluated by immunohistochemical analysis. Compared with nonmetastatic cases, primary tumors of the metastatic group exhibited significantly decreased protein levels of endostatin and its precursor collagen XVIII. Comparison between primary tumors and positive nodes of the metastatic cases revealed decreased expression of collagen XVIII and CBP2/HSP47 in metastases. Angiogenesis is essential for tumor growth and metastasis; accordingly, the observed differences in the immunohistochemical expression of angiogenesis-related proteins in oral SCC with multiple lymph node involvement may provide an explanation for the increased metastatic potential of these tumors.  相似文献   
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PURPOSE: NWTS-5 was a multi-institutional clinical trial for patients less than 16 years of age at diagnosis with specific renal neoplasms who were diagnosed between August 1, 1995 and May 31, 2002. A uniform approach to the treatment of patients with relapse was employed. PATIENTS AND METHODS: Seventy-two patients who relapsed after immediate nephrectomy (stages I and II), initial chemotherapy with vincristine (VCR) and actinomycin D and no radiation therapy were registered on stratum B of the NWTS-5 relapse protocol. Four patients were not evaluable: one due to insufficient data and three due to major protocol violations. Among the 68 remaining patients, one who was 19 years of age at initial diagnosis of Wilms tumor, five with bilateral Wilms tumor at diagnosis, three who developed a contralateral relapse, and one with persistent disease were not included in this analysis. Relapse treatment included surgical excision, when feasible, radiation therapy and alternating courses of VCR, doxorubicin and cyclophosphamide and etoposide and cyclophosphamide. RESULTS: The outcomes of 58 patients were analyzed. The lung was the only site of relapse for 31 patients. Event-free survival 4 years after relapse was 71.1% and 4-year overall survival was 81.8% for all patients and were 67.8 and 81.0% for those who relapsed only to their lungs. The most frequent toxicities were hematological. CONCLUSIONS: These results demonstrate that a significant proportion of children with Wilms tumor who relapse after initial treatment with VCR and actinomycin D can be successfully re-treated.  相似文献   
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