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101.
102.
Hui Chun Zhan Lorraine J Gudas Dean Bok Robert Rando David M Nanus Satish K Tickoo 《Clinical cancer research》2003,9(13):4897-4905
PURPOSE: Retinoids, a group of compounds, including vitamin A (retinol), and related metabolites, have been shown to regulate the growth and differentiation of many types of cells. IFN-alpha and either 13-cis-retinoic acid or liposomal all-trans retinoic acid have been used in the treatment of patients with metastatic renal cell carcinoma. We knew that samples from renal cell carcinomas contained greatly reduced levels of retinol and retinyl esters relative to samples from normal human kidney. This prompted us to examine the levels of LRAT (lecithin:retinol acyltransferase) protein in various subtypes of human kidney cancers relative to normal human kidney by immunohistochemistry. EXPERIMENTAL DESIGN: We examined 31 partial or radical nephrectomy specimens diagnosed with kidney tumors between 1997 and 1998. Representative paraffin-embedded tissue blocks from each tumor, with each containing adjacent nonneoplastic renal parenchyma, were used for immunohistochemical analysis with affinity purified antibodies to human LRAT protein. RESULTS: LRAT protein was detected at high levels in the epithelial cells in the tubules and the lining of Bowman's capsule in the glomeruli of normal, nonneoplastic kidney sections. Among the 31 tumors, there were 13 cases of conventional (clear cell) renal cell carcinoma (RCC; including 2 multilocular cystic RCCs), 7 papillary RCC, 6 chromophobe RCC, 1 RCC, unclassified, and 4 renal oncocytoma. All tumors showed diffuse immunoreactivity for LRAT. In each case, the staining was uniform throughout the tumor, with only minimal variation in the staining intensity between different areas. All 4 renal oncocytomas, 2 of 6 chromophobe RCCs, 1 conventional (clear cell) carcinoma, 1 RCC, unclassified, and 2 conventional RCCs, which were of the multilocular cystic-type stained strongly (3+) for LRAT. In contrast, the remaining conventional RCCs and the papillary RCC samples stained much less intensely for LRAT. Of the 10 tumors that stained 3+ for LRAT in the study, 9 were either benign tumors or tumors with low malignant potential. CONCLUSIONS: These data show that LRAT expression is higher in renal tumors with an indolent biological behavior. Additional studies will ascertain if LRAT possesses any prognostic or therapeutic role in renal cancer. 相似文献
103.
Ravi Salgia Thomas Lynch Arthur Skarin Joan Lucca Cathleen Lynch Ken Jung F Stephen Hodi Michael Jaklitsch Steve Mentzer Scott Swanson Jean Lukanich Raphael Bueno John Wain Douglas Mathisen Cameron Wright Panos Fidias Dean Donahue Shirley Clift Steve Hardy Donna Neuberg Richard Mulligan Iain Webb David Sugarbaker Martin Mihm Glenn Dranoff 《Journal of clinical oncology》2003,21(4):624-630
PURPOSE: We demonstrated that vaccination with irradiated tumor cells engineered to secrete granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates potent, specific, and long-lasting antitumor immunity in multiple murine models and patients with metastatic melanoma. To test whether this vaccination strategy enhances antitumor immunity in patients with metastatic non-small-cell lung cancer (NSCLC), we conducted a phase I clinical trial. PATIENTS AND METHODS: Resected metastases were processed to single-cell suspension, infected with a replication-defective adenoviral vector encoding GM-CSF, irradiated, and cryopreserved. Individual vaccines consisted of 1 x 10(6), 4 x 10(6), or 1 x 10(7) cells, depending on overall yield, and were administered intradermally and subcutaneously at weekly and biweekly intervals. RESULTS: Vaccines were successfully manufactured for 34 (97%) of 35 patients. The average GM-CSF secretion was 513 ng/10(6) cells/24 h. Toxicities were restricted to grade 1 to 2 local skin reactions. Nine patients were withdrawn early because of rapid disease progression. Vaccination elicited dendritic cell, macrophage, granulocyte, and lymphocyte infiltrates in 18 of 25 assessable patients. Immunization stimulated the development of delayed-type hypersensitivity reactions to irradiated, dissociated, autologous, nontransfected tumor cells in 18 of 22 patients. Metastatic lesions resected after vaccination showed T lymphocyte and plasma cell infiltrates with tumor necrosis in three of six patients. Two patients surgically rendered as having no evidence of disease at enrollment remain free of disease at 43 and 42 months. Five patients showed stable disease durations of 33, 19, 12, 10, and 3 months. One mixed response was observed. CONCLUSION: Vaccination with irradiated autologous NSCLC cells engineered to secrete GM-CSF enhances antitumor immunity in some patients with metastatic NSCLC. 相似文献
104.
Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
Methodology:
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Results:
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Conclusion:
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
105.
The management of colorectal cancers, published in a recent issue of Effective Health Care, is reviewed. 相似文献
106.
Laurence C. Baker Kathryn A. Phillips Jennifer S. Haas Su-Ying Liang Dean Sonneborn 《Health services research》2004,39(6P1):1751-1772
Objective. Managed care may have widespread impacts on health care delivery for all patients in the areas where they operate. We examine the relationship between area managed care activity and screening for breast, cervical, and prostate cancer among patients enrolled in more managed care plans and patients who are enrolled in less managed plans.
Data and Methods. Data on cancer screening from the 1996 Medical Expenditure Panel Survey (MEPS) were linked to data on health maintenance organization (HMO) and preferred provider organization (PPO) market share and HMO competition at the metropolitan statistical area (MSA) level. Logistic regression analysis was used to examine the relationship between area managed care prevalence and the use of mammography, clinical breast examination, Pap smear, and prostate cancer screening in the past two years, controlling for important covariates.
Results. Among all patients, increases in area-level HMO market share are associated with increases in the appropriate use of mammography, clinical breast exam, and Pap smear (OR for high relative to low managed care areas are 1.75, p <.01, for mammography, 1.58, p <.05, for clinical breast exam, and 1.71, p <.01, for Pap smear). In analyses of subgroups, the relationship is significant only for individuals who are enrolled in the nonmanaged plans; there is no relationship for individuals in more managed plans. No relationship is observed between area HMO market share and prostate cancer screening in any analysis. Neither the level of competition between area HMOs nor area PPO market share is associated with screening rates.
Conclusions. Area-level managed care activity can influence preventive care treatment patterns. 相似文献
Data and Methods. Data on cancer screening from the 1996 Medical Expenditure Panel Survey (MEPS) were linked to data on health maintenance organization (HMO) and preferred provider organization (PPO) market share and HMO competition at the metropolitan statistical area (MSA) level. Logistic regression analysis was used to examine the relationship between area managed care prevalence and the use of mammography, clinical breast examination, Pap smear, and prostate cancer screening in the past two years, controlling for important covariates.
Results. Among all patients, increases in area-level HMO market share are associated with increases in the appropriate use of mammography, clinical breast exam, and Pap smear (OR for high relative to low managed care areas are 1.75, p <.01, for mammography, 1.58, p <.05, for clinical breast exam, and 1.71, p <.01, for Pap smear). In analyses of subgroups, the relationship is significant only for individuals who are enrolled in the nonmanaged plans; there is no relationship for individuals in more managed plans. No relationship is observed between area HMO market share and prostate cancer screening in any analysis. Neither the level of competition between area HMOs nor area PPO market share is associated with screening rates.
Conclusions. Area-level managed care activity can influence preventive care treatment patterns. 相似文献
107.
108.
Ruth Etzioni Sarah Hawley Dean Billheimer Lawrence D True Beatrice Knudsen 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1040-1046
BACKGROUND: Immunohistochemical studies use antibodies to stain tissues with the goal of quantifying protein expression. However, protein expression is often heterogeneous resulting in variable degrees and patterns of staining. This problem is particularly acute in prostate cancer, where tumors are infiltrative and heterogeneous in nature. In this article, we introduce analytic approaches that explicitly consider both the frequency and intensity of tissue staining. METHODS: Compositional data analysis is a technique used to analyze vectors of unit-sum proportions, such as those obtained from soil sample studies or species abundance surveys. We summarized specimen staining patterns by the proportion of cells staining at mild, moderate, and intense levels and used compositional data analysis to summarize and compare the resulting staining profiles. RESULTS: In a study of Syndecan-1 staining patterns among 44 localized prostate cancer cases with Gleason score 7 disease, compositional data analysis did not detect a statistically significant difference between the staining patterns in recurrent (n = 22) versus nonrecurrent (n = 22) patients. Results indicated only modest increases in the proportion of cells staining at a moderate intensity in the recurrent group. In contrast, an analysis that compared quantitative scores across groups indicated a (borderline) significant increase in staining in the recurrent group (P = 0.05, t test). CONCLUSIONS: Compositional data analysis offers a novel analytic approach for immunohistochemical studies, providing greater insight into differences in staining patterns between groups, but possibly lower statistical power than existing, score-based methods. When appropriate, we recommend conducting a compositional data analysis in addition to a standard score-based analysis. 相似文献
109.
Thioredoxin and its role in toxicology. 总被引:9,自引:0,他引:9
110.
Brian Dean 《Neuropsychopharmacology》2004,29(8):1583-4; author reply 1585-6