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101.
Cisplatin (CDDP), an anticancer drug used extensively to treat a broad range of neoplasms, has strong ototoxic side effects. Sodium thiosulfate (STS) has been described as a protective agent against CDDP toxicity, but it also reduces CDDP's antitumoral cytotoxicity. To maintain the antitumoral effectiveness of systemic administration of CDDP, a strategy has been developed to apply STS directly into the cochlea. Perfusion of STS into the cochleae of guinea pigs completely prevented CDDP-induced hearing loss, with no change in either compound action potential (CAP) or distortion product otoacoustic emission (DPOAE) audiograms during the time course of the treatment. Histological analysis revealed a minimal loss of outer hair cells (OHCs) in the organ of Corti and no damage to the marginal cells of the stria vascularis as seen in animals exposed to CDDP. Cytocochleograms prepared 6 days after CDDP exposure showed that STS treatment protected more than 92.8% of OHCs and IHCs destined to die. Furthermore, it prevented CDDP-induced mitochondrial damage and subsequent translocation of cytochrome c, DNA fragmentation, and suppressed the apoptotic and necrotic hair cell degeneration. These results suggest that local application of STS may be an interesting strategy to prevent CDDP ototoxicity in patients undergoing CDDP chemotherapy.  相似文献   
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An analysis was made of clinical complications, determined with objective methods, in 68 patients at the University Clinic of Navarra with the clinical suspicion of antiphospholipid syndrome (APS) and presence of anticardiolipin antibodies (ACA). Patients with IgG higher than 23 GPL were considered for the study. The most prevalent pathology was thrombosis: venous thrombosis (42.6%) and arterial thrombosis (22%). Other complications were abortions (23.8% of the 42 women) and thrombocytopenia (12.1%). With respect to the localisation of venous thrombosis, predominance corresponded to lower extremities (51.7%), followed by superficial thrombophlebitis (27.5%) and pulmonary thromboembolism (20.6%). Among the arterial complications, the most frequent were cerebrovascular disease (86.6 %) and coronary disease (13.4%). There was no correlation between the presence of high values of ACA and the prevalence or severity of clinical manifestations. In the series of patients with ACA IgG>23 GPL, we appreciated a high percentage of venous and arterial thrombosis detected with objective methods. The presence of ACA constitutes a prothrombotic risk factor  相似文献   
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OBJECTIVES: The metabolism of cells in articular joint tissues in normal and pathological conditions is subject to a complex environmental control. In addition to soluble mediators such as cytokines and growth factors, as well as mechanical stimuli, reactive oxygen species (ROS) emerge as major factors in this regulation. ROS production has been found to increase in joint diseases, such as osteoarthritis and rheumatoid arthritis, but their role in joint diseases initiation and progression remains questionable. METHOD: This review is focused on the role of ROS, mainly nitric oxide, peroxynitrite and superoxide anion radicals, in the signaling mechanisms implied in the main cellular functions, including synthesis and degradation of matrix components. The direct effects of ROS on cartilage matrix components as well as their inflammatory and immunomodulatory effects are also considered. RESULTS: Some intracellular signaling pathways are redox sensitive and ROS are involved in the regulation of the production of some biochemical factors involved in cartilage degradation and joint inflammation. Further, ROS may cause damage to all matrix components, either by a direct attack or indirectly by reducing matrix components synthesis, by inducing apoptosis or by activating latent metalloproteinases. Finally, we have highlighted the uncoupling effect of ROS on tissue remodeling and synovium inflammation, suggesting that antioxidant therapy could be helpful to treat structural changes but not to relieve symptoms. CONCLUSIONS: This review of the literature supports the concept that ROS are not only deleterious agents involved in cartilage degradation, but that they also act as integral factors of intracellular signaling mechanisms. Further investigation is required to support the concept of antioxidant therapy in the management of joint diseases.  相似文献   
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A multi-centre retrospective study involving 4 French university institutions has been conducted in order to identify routine pre-therapeutic prognostic factors of survival in patients with previously untreated non-small cell lung cancer and brain metastases at the time of presentation. A total of 231 patients were recorded regarding their clinical, radiological and biological characteristics at presentation. The accrual period was January 1991 to December 1998. Prognosis was analysed using both univariate and multivariate (Cox model) statistics. The median survival of the whole population was 28 weeks. Univariate analysis (log-rank), showed that patients affected by one of the following characteristics proved to have a shorter survival in comparison with the opposite status of each variable: male gender, age over 63 years, poor performance status, neurological symptoms, serum neuron-specific enolase (NSE) level higher than 12.5 ng ml(-1), high serum alkaline phosphatase level, high serum LDH level and serum sodium level below 132 mmol l(-1). In the Cox's model, the following variables were independent determinants of a poor outcome: male gender: hazard ratio (95% confidence interval): 2.29 (1.26-4.16), poor performance status: 1.73 (1.15-2.62), age: 1.02 (1.003-1.043), a high serum NSE level: 1.72 (1.11-2.68), neurological symptoms: 1.63 (1.05-2.54), and a low serum sodium level: 2.99 (1.17-7.62). Apart from 4 prognostic factors shared in common with other stage IV NSCLC patients, whatever the metastatic site (namely sex, age, gender, performance status and serum sodium level) this study discloses 2 determinants specifically resulting from brain metastasis: i.e. the presence of neurological symptoms and a high serum NSE level. The latter factor could be in relationship with the extent of normal brain tissue damage caused by the tumour as has been demonstrated after strokes. Additionally, the observation of a high NSE level as a prognostic determinant in NSCLC might reflect tumour heterogeneity and understimated neuroendocrine differentiation.  相似文献   
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CONTEXT: The "Standards, Options and Recommendations" (SOR) project, started in 1993, is a collaboration between the Federation of the French Cancer Centres (FNCLCC), the 20 French Cancer Centres and specialists from French Public Universities, General Hospitals and Private Clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and outcome for cancer patients. The methodology is based on literature review and critical appraisal by a multidisciplinary group of experts, with feedback from specialists in cancer care delivery. OBJECTIVES: To develop clinical practice guidelines according to the definitions of the Standards, Options and Recommendations project for the management of locally advanced non small cell lung carcinoma. METHODS: Data were identified by searching Medline and the personal reference lists of members of the expert groups. Once the guidelines were defined, the document was submitted for review to independent reviewers and to the medical committees of the 20 French Cancer Centres. RESULTS: The main recommendations are: 1) The management of the locally advanced non small cell lung carcinoma has two main goals: firstly to obtain local control of the disease (or to at least delay local progression in order to improve the survival or relapse free survival), and secondly to prevent the development of metastases. 2) There is a consensus that locally advanced non small cell lung carcinoma should be irradiated. External beam radiotherapy should be of optimal quality and delivered at a minimal dose of 60 Gy by standard fractionation. For patients with a poor life expectancy, this can be delivered as a split-course or hypofractionated scheme. 3) Treatment for patients with a performance status of 0-1 should consist of short duration induction chemotherapy (with a least two drugs one of which must be cisplatin), combined sequentially with conventional radiotherapy. 4) Surgery is contraindicated in extensive N3 disease. Combined radio-chemotherapy (adjuvant or neoadjuvant) is not indicated outside clinical trials. Surgery is justified in stage N2 disease as good local control can be achieved. T4-N0 disease should be treated surgically with curative intent.  相似文献   
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OBJECTIVE: To determine the molecular epidemiology of tuberculosis isolated from patients cared for at eight hospitals scattered throughout New York City. MATERIALS AND METHODS: Cases of tuberculosis occurring in 1996 and 1997 at collaborating hospitals were identified, and demographic data were extracted from patient charts. All available isolates were analyzed by IS6110 for genetic relatedness. The molecular fingerprints were compared both to each other and to the larger repository of strains from New York City developed and maintained at the Public Health Research Institute. RESULTS: One hundred and eighty cases were fully characterized. Compared with New York City cases, study patients were more likely to be Asian and less likely to be non-Hispanic blacks. Overall, 97 (54%) of the cases were clustered with respect to other study strains or with respect to the other New York City isolates. Clustered strains were significantly more likely to be from non-Hispanic blacks or patients born in the United States. The largest cluster (n = 17) was the "W" strain previously associated with an outbreak of multidrug-resistant tuberculosis in New York City. In the current study, the majority of W strain isolates were fully drug-susceptible. CONCLUSIONS: High rates of genetically related tuberculosis continue to occur among patients in New York City, in spite of improved control of nosocomial outbreaks and dramatic decreases in the overall case rates. The use of molecular techniques to suggest patterns of transmission has become essential in developing and assessing routine tuberculosis control strategies.  相似文献   
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