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91.
Interleukin-6 (IL-6) protects multiple myeloma cells against apoptosis induced by glucocorticoids. Here, we investigated whether inhibition of the IL-6 signaling pathway by the IL-6 receptor superantagonist Sant7 enhances the in vivo antitumor effects of dexamethasone on the IL-6-dependent multiple myeloma cell line INA-6. For this purpose, we used a novel murine model of human multiple myeloma in which IL-6-dependent INA-6 multiple myeloma cells were directly injected into human bone marrow implants in severe combined immunodeficient (SCID) mice (SCID-hu). The effect of in vivo drug treatments on multiple myeloma cell growth was monitored by serial determinations of serum levels of soluble IL-6 receptor (shuIL-6R), which is released by INA-6 cells and served as a marker of tumor growth. In SCID-hu mice engrafted with INA-6 cells, treatment with either Sant7 or dexamethasone alone did not induce significant reduction in serum shuIL-6R levels. In contrast, the combination of Sant7 with dexamethasone resulted in a synergistic reduction in serum shuIL-6R levels after 6 consecutive days of treatment. Gene expression profiling of INA-6 cells showed down-regulation of proliferation/maintenance and cell cycle control genes, as well as up-regulation of apoptotic genes in multiple myeloma cells triggered by Sant7 and dexamethasone combination. In vitro colony assays showed inhibition of myeloid and erythroid colonies from normal human CD34(+) progenitors in response to dexamethasone, whereas Sant7 neither inhibited colony growth nor potentiated the inhibitory effect of dexamethasone. Taken together, these results indicate that inhibition of IL-6 signaling by Sant7 significantly potentiates the therapeutic action of dexamethasone against multiple myeloma cells, providing the preclinical rationale for clinical trials of Sant7 in combination with dexamethasone to improve patient outcome in multiple myeloma.  相似文献   
92.
Serum PDGF-AB in pleural mesothelioma.   总被引:2,自引:0,他引:2  
Overexpression of platelet-derived growth factor (PDGF) has been observed in lung and pleural tumors. The aim of this study was to evaluate the diagnostic and prognostic role of serum PDGF in pleural mesothelioma (PM). Four groups of subjects were studied: 93 malignant PM patients, 33 primary non small cell lung cancer patients, 51 subjects exposed to asbestos, defined as high-risk controls, and 24 healthy controls. PDGF-AB mean concentration was higher in PM patients (45.8 ng/ml) than in high-risk controls (33.1 ng/ml) and healthy controls (26.8 ng/ml). Using the cut-off level of 49.8 ng/ml, corresponding to the mean+2SD of PDGF-AB in healthy controls, 43% of PM patients showed positive PDGF-AB levels. Survival was evaluated in 82 PM patients. At the end of the follow-up (median 9.8 months) 80.5% of patients had died. Median survival was 13.1 and 7.9 months for patients with PDGF-AB lower and higher than the cut-off, respectively. Adjusting for age, sex, histology and platelet count, positive PDGF-AB levels were associated with lower survival (OR=1.2, 95%CI: 0.9-1.6), even if not significantly so. In conclusion, serum PDGF may represent a useful additional parameter to prognostic factors already available for PM.  相似文献   
93.
A 1H and 13C NMR study on the inclusion complex of paroxetine with β-cyclodextrin was carried out in order to define the stoichiometry of the association and its strength. Proton and carbon chemical shift measurements of paroxetine and β-cyclodextrin were performed at several molar ratios and temperatures, allowing the determination of a 1:1 stoichiometry and an association constant value of the order of 2 × 103 for the paroxetine–β-cyclodextrin complex. Overhauser effects in the rotating frame were also measured, and the experimental interproton distance constraints have been used for molecular model building of the complex. The obtained model indicates that the benzodioxolyl moiety of paroxetine is deeply inserted in the cavity of the cylindrical structure of β-cyclodextrin, while the fluoro-phenyl ring lays above the wider rim.  相似文献   
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Radon is the second leading cause of lung cancer among smokers and the leading cause among nonsmokers. The Centers for Disease Control and Prevention’s National Comprehensive Cancer Control Program (NCCCP) funds every state, seven tribes, seven territories and the District of Columbia to develop formal cancer plans that focus efforts in cancer control. A 2010 review of cancer plans identified radon-related activities in 27 (42%) plans. Since then, 37 coalitions have updated their plans with new or revised cancer control objectives. There has also been recent efforts to increase awareness about radon among cancer coalitions. This study assesses NCCCP grantees current radon activities and changes since the 2010 review. We reviewed all 65 NCCCP grantee cancer plans created from 2005 to 2015 for radon related search terms and categorized plans by radon activities. The program’s most recent annual progress report to CDC was also reviewed. We then compared the results from the updated plans with the findings from the 2010 review to assess changes in radon activities among cancer coalitions. Changes in state radon laws between 2010 and 2015 were also assessed. While a number of cancer plans have added or expanded radon-specific activities since 2010, approximately one-third of NCCCP grantees still do not include radon in their cancer plans. Cancer programs can consider addressing radon through partnership with existing radon control programs to further reduce the risk of lung cancer, especially among non-smokers.  相似文献   
97.
ObjectivePoor oral status, represented by partial/complete tooth loss, may lead to changes in food choice, which may ultimately lead to underweight, overweight, or obesity. The aim of this study is to evaluate whether poor oral status is associated with underweight or overweight/obesity, regardless of physical activity.MethodsThis cross-sectional study is part of a major project, The Frailty in Brazilian Elderly Study, carried out in Campinas, Brazil (2008–2009). The sample was composed of 900 independent-living older adults. Complete data were available for 875 individuals including sociodemographic, self-reported amount of medications used and eating difficulty questionnaire, smoking habit, depressive symptoms, physical activity, oral examination, and anthropometric assessments according to the WHO criteria. Body mass index was used as an outcome. Multinomial logistic regression was adjusted for confounding variables.ResultsThe mean age of the sample was 72.7 y (±5.81) and the prevalence of edentulism was 47.7%. Edentate individuals not wearing dentures were more likely to be underweight [odds ratio (OR) = 3.94, 95% confidence interval (CI) 1.14–13.64] and overweight/obese (OR = 2.88, 95%CI 1.12–7.40). Males (OR = 0.56, 95%CI 0.36–0.85) and those not using medications (OR = 0.41 95%CI 0.24–0.70) were less likely to be overweight/obese. Individuals who smoke (OR = 2.62, 95%CI 1.26–5.44) were more likely to be underweight. Older individuals with family income between 3.1 and 5 minimum wage (OR = 1.69, 95%CI 1.00–2.87) were more likely to be overweight/obese.ConclusionTo our knowledge, this is one of the first studies associating poor oral health, represented by edentulism not rehabilitated with dentures, with unfavorable body mass, regardless of the two major confounders, physical activity and depression symptoms.  相似文献   
98.
Despite recent therapeutic advances, multiple myeloma (MM) is still an incurable neoplasia due to intrinsic or acquired resistance to therapy. Myeloma cell localization in the bone marrow milieu allows direct interactions between tumor cells and non-tumor bone marrow cells which promote neoplastic cell growth, survival, bone disease, acquisition of drug resistance and consequent relapse. Twenty percent of MM patients are at high-risk of treatment failure as defined by tumor markers or presentation as plasma cell leukemia. Cumulative evidences indicate a key role of Notch signaling in multiple myeloma onset and progression. Unlike other Notch-related malignancies, where the majority of patients carry gain-of-function mutations in Notch pathway members, in MM cell Notch signaling is aberrantly activated due to an increased expression of Notch receptors and ligands; notably, this also results in the activation of Notch signaling in surrounding stromal cells which contributes to myeloma cell proliferation, survival and migration, as well as to bone disease and intrinsic and acquired pharmacological resistance. Here we review the last findings on the mechanisms and the effects of Notch signaling dysregulation in MM and provide a rationale for a therapeutic strategy aiming at inhibiting Notch signaling, along with a complete overview on the currently available Notch-directed approaches.  相似文献   
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