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31.
Classical cytotoxic treatment of rhabdomyosarcoma (RMS), the most common soft tissue malignancy in children, is often accompanied by significant morbidity and poor response. Chemotherapy may induce multidrug resistance (MDR) associated with the expression of P-glycoprotein, a drug efflux pump which modifies the sensitivity of tumoral cells to drugs. To analyze MDR in RMS we used the RMS-GR cell line, obtained from an embryonal rhabdomyosarcoma treated in vivo with polychemotherapy. The RMS-GR cells showed cross-resistance to vincristine, doxorubicin and actinomycin D, the drugs of choice in the conventional treatment of RMS. Polymerase chain reaction (PCR) analysis showed that these RMS cells overexpressed mdr1 /P-glycoprotein. The pattern of resistance and the level of P-glycoprotein expression were similar to those found in the resistant RMS TE.32.7.DAC cell line obtained in vitro . Southern blot analysis showed that mdr1 overexpression was not due to amplification of the gene. Our results showed that the in vivo treatment of embryonal RMS may induce an MDR phenotype mediated by mdr1 /P-glycoprotein in RMS cells.  相似文献   
32.
The oxidative polymorphism of debrisoquine has been determined in 125 patients with bladder cancer and in 556 healthy control subjects; 96.6% of patients and 93.9% of controls with a metabolic ratio of debrisoquine less than 12.6 were classified as extensive metabolizers of debrisoquine (P = NS). The distribution of frequencies of metabolic ratio values tended to have lower values in the patients (P less than 0.05), reflecting a higher oxidative rate of debrisoquine in urothelioma patients that cannot be explained solely in terms of enzymatic induction by drugs, tobacco or alcohol. Patients with a high occupational risk for urothelioma had lower metabolic ratio values (P = 0.03). Our results suggest that oxidative polymorphism of debrisoquine might be related to the pathogenesis of bladder cancer.  相似文献   
33.
Hyperfractionated irradiation for adults with brainstem gliomas   总被引:2,自引:0,他引:2  
Hyperfractionated irradiation appears to have improved survival for pediatric patients with brainstem gliomas. However, the efficacy and safety of this technique are less well established for adults with brainstem tumors. In 1984 the UCSF Department of Radiation Oncology began treating adults with brainstem gliomas using 100 cGy fractions given twice daily to total doses ranging between 6600-7800 cGy (median dose 7200 cGy). By the end of 1989, a total of 14 patients had been irradiated with follow-up times for surviving patients ranging between 4-69 months (median follow-up 33 months). Tumor histologies included five moderately anaplastic astrocytomas, one highly anaplastic astrocytoma, and eight which were unbiopsied. At the time of this analysis, six patients had failed locally, with five dying as a result of recurrent tumor. There were no deaths caused by complications or intercurrent illness. The 3-year actuarial survival rate was 59%, with a corresponding 3-year actuarial local control rate of 48%. The projected median survival was in excess of 5 years, whereas the actuarial median time to progression was 31 months (134 weeks). The treatments were well tolerated: the mean pretreatment Karnofsky Performance Status was 74% (range 60-90%); at the end of treatment the mean KPS was 78% (range 60-100%). In terms of neurologic status, six patients improved by the end of treatment, seven were stable, and one experienced only minor deterioration without change in KPS. There were no significant long-term complications (specifically, no instances of either radiation brain necrosis or myelitis). Seven patients required prolonged steroid administration after completing radiotherapy; six of these eventually recurred locally. These results appear to be substantially better than those achieved using conventional radiotherapy regimens, and suggest that this technique merits further investigation.  相似文献   
34.
Achieving effective treatment outcomes for patients with glioblastoma (GBM) has been impeded by many obstacles, including the pharmacokinetic limitations of antitumor agents, such as topotecan (TPT). Here, we demonstrate that intravenous administration of a novel nanoliposomal formulation of TPT (nLS-TPT) extends the survival of mice with intracranial GBM xenografts, relative to administration of free TPT, because of improved biodistribution and pharmacokinetics of the liposome-formulated drug. In 3 distinct orthotopic GBM models, 3 weeks of biweekly intravenous therapy with nLS-TPT was sufficient to delay tumor growth and significantly extend animal survival, compared with treatment with free TPT (P ≤ .03 for each tumor tested). Analysis of intracranial tumors showed increased activation of cleaved caspase-3 and increased DNA fragmentation, both indicators of apoptotic response to treatment with nLS-TPT. These results demonstrate that intravenous delivery of nLS-TPT is a promising strategy in the treatment of GBM and support clinical investigation of this therapeutic approach.  相似文献   
35.
PURPOSE: To evaluate the feasibility of gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy for patients with newly diagnosed glioblastoma. METHODS AND MATERIALS: From April 1999 to May 2002, 21 patients with glioblastoma multiforme were enrolled on a Phase I protocol investigating planned gross total resection and immediate placement of permanent I-125 seeds, followed by postoperative hyperfractionated radiotherapy to a dose of 60 Gy at 100 cGy b.i.d., 5 days per week. Median age and Karnofsky performance status were 50 years (range, 32-65 years) and 90 (range, 70-100), respectively. Toxicity was assessed according to Radiation Therapy Oncology Group criteria. RESULTS: Eighteen patients completed treatment according to protocol. The median preoperative tumor volume on magnetic resonance imaging was 18.6 cm(3) (range, 4.4-41.2 cm(3)). The median brachytherapy dose measured 5 mm radially outward from the resection cavity was 400 Gy (range, 200-600 Gy). Ten patients underwent 12 reoperations, with 11 of 12 reoperations demonstrating necrosis without evidence of tumor. Because of high toxicity, the study was terminated early. Median progression-free survival and overall survival were 57 and 114 weeks, respectively, but not significantly improved compared with historical patients treated at University of California, San Francisco, with gross total resection and radiotherapy without brachytherapy. CONCLUSIONS: Treatment with gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy as performed in this study results in high toxicity and reoperation rates, without demonstrated improvement in survival.  相似文献   
36.
Successful kidney transplantation reduces hyperplastic parathyroid gland   总被引:1,自引:0,他引:1  
INTRODUCTION: In dialysis patients, the parathyroid glands (PTGs) may increase progressively, producing abnormal bone metabolism. Changes in PTG volume among patients with hyperplastic PTGs are not well known after kidney transplantation. This study investigated PTG volume by ultrasound (US). METHODS: US of PTG was performed immediately (US-0) and 12 months after (US-12) transplantation to identify glands in all recipients. We calculated the percentage reduction in PTG volume (R%PTG). We declared it significant when it was > or =35%. Bone biochemical markers and renal function were recorded sequentially. RESULTS: Among engrafted patients, parathyroid US-0 was performed in 47 and US-0 and US-12 in 36. Some visible gland was observed upon US-0 in 13 recipients, a group that showed higher pretransplantation parathyroid hormone (PTH) levels than the remaining 34 patients with no visible glands (627 +/- 360.0 vs 280 +/- 240.9 pg/mL; P < .05). Of 36 recipients with US-0 and US-12, the baseline study identified PTGs in 12 patients (p+ group), while the remaining 24 had no identified glands (p- group). In the p+ group, no PTG, at US-12 were visible in four patients, and a significant R%PTG was observed in three at this time, representing a reduction in gland volume after transplantation among 58.3% of p+ patients. There was a progressive reduction in PTH among both groups. Patients with glandular volume reduction displayed better renal function: serum creatinine 1.7 +/- .79 versus 2.9 +/- .74 mg/dL (P < .05). CONCLUSIONS: Transplantation reversed hyperparathyroidism and PTG volume among recipients who achieved nearly normal renal function.  相似文献   
37.

Background

Laboratory and clinical data suggest that the anti-angiogenic agent, thalidomide, if combined with cytotoxic agents, may be effective against recurrent glioblastoma multiforme (GBM).

Objectives

To determine 6-month progression-free survival (6PFS) and toxicity of temozolomide plus thalidomide in adults with recurrent GBM.

Patients and methods

Eligible patients had recurrent GBM after surgery, radiotherapy, and/or adjuvant chemotherapy. Temozolomide was given at 150–200 mg/m2/day on days 1–5 of each 28-day cycle. Thalidomide was given orally at 400 mg at bedtime (days 1–28) and increased to 1,200 mg as tolerated. Patients were evaluated with magnetic resonance imaging scans every 56 days. The study was designed to detect an increase of the historical 6PFS for GBM from 10 to 30%.

Results

Forty-four patients were enrolled, 43 were evaluable for efficacy and safety. The study population included 15 women, 29 men; median age was 53 years (range 32–84); median Karnofsky performance status was 80% (range 60–100%). Thirty-six (82%) patients were chemotherapy-naïve. There were 57 reports of toxicity of grade 3 or greater. Non-fatal grade 3–4 granulocytopenia occurred in 15 patients (34%). The objective response rate was 7%. The estimated probability of being progression-free at 6 months with this therapy is 24% [95% confidence interval (C.I.) 12–38%]. The median time to progression is 15 weeks (95% C.I. 10–20 weeks). There was no observed correlation between serum levels of vascular endothelial growth factor, basic fibroblast growth factor, and IL-8 and the 6PFS outcome.

Conclusion

This drug combination was reasonably safe, but with little indication of improvement compared to temozolomide alone.  相似文献   
38.
Soft multifocal simultaneous image contact lenses have boomed in recent years due to the growing number of presbyopic patients demanding visual solutions, allowing them to maintain their current standard of living. The concept of ‘simultaneous image’ is based on blur interpretation and/or blur tolerance of superimposed multiple images on the retina formed by various powers of a contact lens. This is the basis for a specific type of multifocal contact lens developed for the compensation of presbyopia. Manufacturers have released a great variety of soft simultaneous image lens designs to meet different patient needs but their fitting is still unsatisfactory in some cases. Some presbyopes discontinue wearing contact lenses due to some limitations in visual quality and comfort that can be overcome with an appropriate contact lens selection based on a comprehensive pre‐fitting evaluation. This paper aims to review the different types of soft multifocal contact lenses that are currently available for presbyopic correction and to define the steps and factors crucial for their fitting, such as pupil, aberrations, accommodation and centring. A discussion about useful tools to achieve a customised fitting leading to a successful outcome, such as the defocus curve, power profile and questionnaires, is performed.  相似文献   
39.
40.
We present the incidence the esophageal squamous cell carcinoma in Asturias, based on the review of the clinical histories of eleven years (1975-85). Of 356 total cases, 92.4% were male patients and the remaining 7.6% females; the relation M:F was 12.2:1. Mean age at the time of diagnosis was 59.4 +/- 9.6 for males and 70 +/- for females. Total annual incidence was 2.8 +/- 0.8 cases/10(5) + population/year. Maximal annual incidence was registered in 1981: 1.1 cases/10(5) population/year. Asturias has eight health districts; those with highest incidence were mining areas: Mieres, Cangas de Narcea and Ria?o. Compared to that of some developing countries, the incidence of esophageal cancer in Asturias is low, similar to that in European countries (except France) and white population of the USA; there is an aggregation of cases in males living in mining areas.  相似文献   
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