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101.
The combination of platinum and paclitaxel is the standard treatment of advanced ovarian carcinoma; however, recent studies have questioned the actual role of the combination as compared to either of the two agents alone. We report an open-label, two-center, phase II study of upfront paclitaxel for patients with histological diagnosis of stage III ovarian carcinoma. Treatment consisted of paclitaxel at 175 mg/m2 administered in a 3-h infusion every 21 days. Response was evaluated after the third course by either laparoscopy or exploratory laparotomy. Patients with stable or progressive disease discontinued treatment, whereas responding patients continued treatment until a maximum of six courses. Response, toxicity, time to progression (TTP) and survival were evaluated. From November 1993 to December 1995, 30 patients were accrued. All patients underwent primary cytoreduction; 17 (57%) and 13 (43%) patients had residual tumors <2 and >2 cm, respectively. Of 27 patients evaluable, objective responses were seen in 18 (66.4%) (95% CI 49.5-83.2)--12 complete (45%) and six partial (22%). Four patients had stable disease (15%) and five (18%) patients progressed. A total of 149 courses were administered to 30 patients, median 4 (range 1-6). Grade 3/4 neutropenia was seen in 13% of courses, peripheral neuropathy, myalgia and arthralgia were frequent, but transitory and relieved with analgesics. At a median follow-up time of 44.5 months (0-99) the TTP and median survival were 16.6 and 43.1 months, respectively. We conclude that single-agent paclitaxel is an effective and well-tolerated first-line treatment for advanced ovarian carcinoma.  相似文献   
102.
Modern management of locally advanced cervical carcinoma   总被引:3,自引:0,他引:3  
Radiation was until recently the key and only modality for the routine treatment of locally advanced cervical carcinoma. However after years of studying multi-modality treatments as an alternative to radiation alone in randomized phase III trials, the standard treatment has changed to chemo-radiation based on cisplatin. Three recent meta-analyses have confirmed that cisplatin-based chemo-radiation adds an absolute 12% benefit in five-year survival over radiation therapy alone. Neoadjuvant chemotherapy followed by radiation has not been of proven benefit, but when neoadjuvant chemotherapy is followed by surgery, an absolute increase of 15% in five-year survival over radiation alone is seen. This benefit in survival is comparable to that obtained with the current chemo-radiation schedules based on cisplatin. Despite these encouraging results there remains room for improvement as the five-year survival of patients treated with chemo-radiation ranges from nearly 80% in bulky IB tumours to only 25% in stage IVA disease. Other therapeutic approaches need to be fully evaluated including the use of chemo-radiation after neoadjuvant chemotherapy; the use of new drug combinations and the multi-modality combination of neoadjuvant chemotherapy followed by radical surgery plus adjuvant chemo-radiation. Likewise, the addition of radiosensitizers to cisplatin, preoperative chemo-radiation and/or adjuvant chemotherapy may eventually improve the currents results of cisplatin-based chemo-radiation. Nevertheless, it is hard to foresee a dramatic increase in cure rate, even with the most optimal combination of cytotoxic drugs, surgery and radiation, and thus the testing of molecular targeted therapies against cervical cancer is a logical step to follow.  相似文献   
103.
It is known that cell-free DNA circulates in plasma/serum of patients with cancer and that part of this DNA circulates as nucleosomes that can be quantified by ELISA. We analyzed the effect of tumor and chemotherapy upon the levels of nucleosomes in vitro, in vivo and in cervical cancer patients. The levels of nucleosomes pre- and post-treatment were correlated with response in 11 patients receiving chemotherapy. Nucleosomes were determined in nude mice treated with or without cisplatin and carrying tumors generated with HeLa cells, and in the cell lysate and supernatant of HeLa cells exposed to cisplatin in culture. In addition, nucleosomes were determined at different time points in patients and in rats receiving chemotherapy. Nucleosomes were higher in patients that controls (1,760 vs. 601, p = 0.0001). After 24 hr of treatment with oxaliplatin and gemcitabine, the levels decreased in 6 patients of whom 5 had response. Nucleosome levels differed between mice xenografted and not xenografted (765 vs. 378, p = 0.001) and between xenografted treated with or without cisplatin (650 vs. 765, p = 0.010), but not in tumor-free animals treated and untreated with cisplatin (378 vs. 379, p = 0.99). In vitro, nucleosomes reached at peak 8 hr in cell lysates to decrease thereafter, whereas in supernatant, levels continued to increase up to 24 hr. Serial determination of nucleosomes in patients showed a rise within 6-12 hr and then a reduction to below the basal at 24 hr. In rats, nucleosomes had no major changes in those receiving oxaliplatin or the triple combination of cisplatin, gemcitabine and paclitaxel as compared to untreated controls. An overdose of this triple combination produced a transient elevation of almost 1,000 AU over the basal. Our results demonstrate that most of circulating nucleosomes originate from the tumor and that chemotherapy produces an early rise most likely due to tumor apoptosis and that nucleosomes are rapidly cleared from circulation. On the contrary, chemotherapy within the therapeutic range of doses has no effect on nucleosome levels in healthy mice and rats. This data suggests that the determination of circulating nucleosomes pre- and post-treatment could be a useful test to predict response to chemotherapy in cancer patients.  相似文献   
104.
105.
OBJECTIVES: To investigate the association between the three human retroviruses, HIV-1, HIV-2 and HTLV-I. DESIGN: Community-based follow-up studies of retrovirus infections in two cohorts. METHODS: A total of 2057 individuals aged 35 years and over were eligible for inclusion. Participants were interviewed and had a blood sample drawn. Samples were analysed for HIV-1, HIV-2 and HTLV infections. Uni- and multivariate analyses that included behavioural and socio-economic factors were performed using logistic regression and Poisson regression models. RESULTS: A total of 1686 individuals participated with a blood sample in the HIV prevalence analyses and 1581 individuals participated in the HTLV-I prevalence analyses. The overall prevalence was 2.1% for HIV-1, 13.5% for HIV-2 and 7.1% for HTLV-I. Comparing the < 45 year age group with 45+ year age groups, the female : male (F : M) prevalence ratio increased with age for all three retroviruses. Dual infections were more common in women than in men. Assuming independent distribution of the viruses, the observed prevalence of dual infections in women was significantly higher than expected, while the prevalence was not increased in men. The prevalence of dual infections increased with age in women, the odds ratio (OR) being 3.4 [95% confidence interval (CI), 1.0-11.3] for any combination of dual infection, while the prevalence decreased with age in men (OR, 0.3; 95% CI, 0.1-2.0) (test of interaction, P = 0.033). Control for behavioural factors did not modify these patterns. CONCLUSIONS: The pattern of increased prevalence among older women could have public health implications; women of older age groups should be regarded as a potential vulnerable group and included in HIV/AIDS prevention programmes.  相似文献   
106.
107.
The aim of this study was to explore whether there are networks of regions where maturation of white matter and changes in brain activity show similar developmental trends during childhood. In a previous study, we showed that during childhood, grey matter activity increases in frontal and parietal regions. We hypothesized that this would be mediated by maturation of white matter. Twenty-three healthy children aged 8-18 years were investigated. Brain activity was measured using the blood oxygen level-dependent (BOLD) contrast with functional magnetic resonance imaging (fMRI) during performance of a working memory (WM) task. White matter microstructure was investigated using diffusion tensor imaging (DTI). Based on the DTI data, we calculated fractional anisotropy (FA), an indicator of myelination and axon thickness. Prior to scanning, WM score was evaluated. WM score correlated independently with FA values and BOLD response in several regions. FA values and BOLD response were extracted for each subject from the peak voxels of these regions. The FA values were used as covariates in an additional BOLD analysis to find brain regions where FA values and BOLD response correlated. Conversely, the BOLD response values were used as covariates in an additional FA analysis. In several cortical and sub-cortical regions, there were positive correlations between maturation of white matter and increased brain activity. Specifically, and consistent with our hypothesis, we found that FA values in fronto-parietal white matter correlated with BOLD response in closely located grey matter in the superior frontal sulcus and inferior parietal lobe, areas that could form a functional network underlying working memory function.  相似文献   
108.
109.
There is growing concern that air pollution exposure increases the risk of lung cancer. The mechanism of action is related to particle-induced oxidative stress and oxidation of DNA. Humans exposed to urban air with vehicle emissions have elevated levels of oxidized guanine bases in blood cells and urine. Animal experimental studies show that pulmonary and gastrointestinal exposure is associated with elevated levels of oxidized guanines in the lung and other organs. Collectively, there is evidence indicating that exposure to traffic-related air pollution particles is associated with oxidative damage to DNA and this might be associated with increased risk of cancer.  相似文献   
110.
Hormesis, the beneficial effects of mild stress exposures, is a well documented phenomenon in a range of organisms. The documentation mainly relies on relatively simple and controlled laboratory investigations. In order to better understand hormesis and predict the outcome of more complex and realistic conditions, a number of key issues should be investigated in much more detail. One obstacle is the development of precise treatments optimized for single individuals. Only then can we progress with the use of hormesis as a therapeutic tool for humans.  相似文献   
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