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991.
Tumor necrosis factor (TNF)-alpha is a major effector and regulatory cytokine with a pleiotropic role in the pathogenesis of several immune-regulated diseases, including graft versus host disease (GVHD) and hematologic malignancies, such as multiple myeloma (MM), myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML). Curative treatment for the above diseases are not currently available for most patients. Therapeutic approaches inactivating or blocking TNF-alpha are being evaluated in clinical trials. This review describes the development of the soluble TNF-alpha receptor (p75 TNF-R: Fc; etanercept) and other agents inactivating or blocking TNF-alpha in the management of patients with hematologic malignancies. The satisfactory safety profile of etanercept--as demonstrated in patients with autoimmune diseases--has been confirmed in patients with hematologic malignancies and GVHD. Studies to assess whether etanercept, either as a single agent or in combination with cytotoxic and/or immune therapy, may increase response rates and/or survival in patients with MM, MDS, AML and other hematologic malignancies are now warranted. 相似文献
992.
A survival-stratification model of human colorectal carcinomas with beta-catenin and p27kip1 总被引:6,自引:0,他引:6
BACKGROUND: The stabilization and nuclear translocation of beta-catenin are early events in the majority of sporadic colorectal carcinomas (CRC). beta-catenin up-regulates c-Myc and cyclin D1, which antagonize the association of the cyclin-dependent kinase (Cdk) inhibitor, p27(kip1), with Cdk2, thus allowing cell cycle progression through G1 to S-phase. Lack of p27 is a significant predictor of poor survival in a series of 136 CRC specimens. A combination of molecules in the same pathway may be a better prognostic factor. METHODS: The expression of beta-catenin, c-Myc, and cyclin D1 in relation to patients' survival and clinicopathologic parameters in the same series was evaluated by immunohistochemistry. RESULTS: Intense nuclear overexpression of beta-catenin, but not a lack of cell membrane or cytoplasmic expression, is a significant predictor of poor survival by both univariate (P = 0.0029) and multivariate analyses (P = 0.004, risk ratio =3.8), suggesting that beta-catenin is retained in the nucleus to function as an oncogene. None of the patients with high nuclear beta-catenin and low p27 expression survived 5 years or more whereas 65% of patients with all other combinations of the two markers survived (P < 0.0001). This combination is also a significant and independent prognostic factor (P = 0.001; risk ratio = 9.7). Overexpression of c-Myc is associated with higher mortality rates, but the expression of cyclin D1 has no prognostic significance. CONCLUSIONS: The combined expression of beta-catenin and p27 can stratify patients into markedly different survival groups, possibly via their antagonistic effects on metastasis promotion. 相似文献
993.
Galectin-1 modulates human glioblastoma cell migration into the brain through modifications to the actin cytoskeleton and levels of expression of small GTPases 总被引:10,自引:0,他引:10
Camby I Belot N Lefranc F Sadeghi N de Launoit Y Kaltner H Musette S Darro F Danguy A Salmon I Gabius HJ Kiss R 《Journal of neuropathology and experimental neurology》2002,61(7):585-596
We show that high-grade astrocytic tumors with high levels of galectin-1 expression are associated with dismal prognoses. The immunohistochemical analysis of galectin-1 expression of human U87 and U373 glioblastoma xenografts from the brains of nude mice revealed a higher level of galectin-1 expression in invasive areas rather than non-invasive areas of the xenografts. Nude mice intracranially grafted with U87 or U373 cells constitutively expressing low levels of galectin-1 (by stable transfection of an expression vector containing the antisense mRNA of galectin-1) had longer survival periods than those grafted with U87 or U373 cells expressing normal levels of galectin-1. Galectin-1 added to the culture media markedly and specifically increased cell motility levels in human neoplastic astrocytes. These effects are related to marked modifications in the organization of the actin cytoskeleton and the increase in small GTPase RhoA expression. All the data obtained indicate that galectin-1 enhances the migratory capabilities of tumor astrocytes and, therefore, their biological aggressiveness. 相似文献
994.
Randomized,comparative study of interferon beta-1a treatment regimens in MS: The EVIDENCE Trial 总被引:11,自引:0,他引:11
Panitch H Goodin DS Francis G Chang P Coyle PK O'Connor P Monaghan E Li D Weinshenker B;EVIDENCE Study Group. EVidence of Interferon Dose-response: Europian North American Compartative Efficacy;University of British Columbia MS/MRI Research Group 《Neurology》2002,59(10):1496-1506
BACKGROUND: Interferon beta (IFNbeta) reduces relapses and MRI activity in relapsing-remitting MS (RRMS), with variable effects on disability. The most effective dose regimen remains controversial. METHODS: This randomized, controlled, multicenter trial compared the efficacy and safety of IFNbeta-1a (Rebif) 44 micro g subcutaneously three times weekly (tiw), and IFNbeta-1a (Avonex) 30 micro g IM once weekly (qw) in 677 patients with RRMS. Assessors blinded to treatment performed neurologic and MRI evaluations. The primary endpoint was the proportion of patients who were relapse free at 24 weeks; the principal MRI endpoint was the number of active lesions per patient per scan at 24 weeks. RESULTS: After 24 weeks, 74.9% (254/339) of patients receiving IFNbeta-1a 44 micro g tiw remained relapse free compared with 63.3% (214/338) of those given 30 micro g qw. The odds ratio for remaining relapse free was 1.9 (95% CI, 1.3 to 2.6; p = 0.0005) at 24 weeks and 1.5 (95% CI, 1.1 to 2.1; p = 0.009) at 48 weeks, favoring 44 micro g tiw. Patients receiving 44 micro g tiw had fewer active MRI lesions (p < 0.001 at 24 and 48 weeks) compared with those receiving 30 micro g qw. Injection-site reactions were more frequent with 44 micro g tiw (83% vs 28%, p < 0.001), as were asymptomatic abnormalities of liver enzymes (18% vs 9%, p = 0.002) and altered leukocyte counts (11% vs 5%, p = 0.003) compared with the 30 micro g qw dosage. Neutralizing antibodies developed in 25% of 44 micro g tiw patients and in 2% of patients receiving 30 micro g qw. CONCLUSIONS: IFNbeta-1a 44 micro g subcutaneously tiw was more effective than IFNbeta-1a 30 micro g IM qw on all primary and secondary outcomes investigated after 24 and 48 weeks of treatment. 相似文献
995.
Hyperhomocysteinemia and venous thromboembolism: a risk factor more prevalent in the elderly and in idiopathic cases 总被引:2,自引:0,他引:2
Hainaut P Jaumotte C Verhelst D Wallemacq P Gala JL Lavenne E Heusterspreute M Zech F Moriau M 《Thrombosis research》2002,106(2):121-125
Fasting plasma homocysteine level and the related clinical findings were analysed in 240 consecutive patients with venous thromboembolism. Hyperhomocysteinemia, defined as a plasma level above 20 micromol/l (corresponding to the percentile 95th in the controls), was present in 11.2% of the patients. Plasma homocysteine level was similar in patients presenting with either deep venous thrombosis, pulmonary embolism or both conditions. It was significantly higher in patients with primary (unprovoked) VTE than in patients with secondary disease (associated with at least one risk factor): 12.3 vs. 9.55 micromol/l (p < 0.005). Mean homocysteine was higher in male than in female patients (14.51 vs. 12.9 micromol/l, p < 0.05) and increased significantly with age. Hyperhomocysteinemia was more frequent in patients with relapsing disease (14 of 76, 18.4%) than in those presenting with a single episode (13 of 164, 7.9%) (p = 0.034). Furthermore, hyperhomocysteinemia was correlated with reduced protein C level (p = 0.013). In a multivariate analysis, two factors were significantly associated with hyperhomocysteinemia: older age (p < 0.0001) and idiopathic occurrence (p < 0.02). Since the frequency of homozygous MTHFR thermolabile variant was rather similar in patients and controls, testing for C677T mutation was not helpful in screening VTE patients. However, the homozygous mutation was significantly more prevalent among hyperhomocysteinemia patients, confirming its role in the genesis of hyperhomocysteinemia. According to its prevalence, to the putative role in venous and arterial disease and the availability of an effective and low-cost corrective therapy, hyperhomocysteinemia deserves interest, especially in the elderly and in the patients with idiopathic VTE disease. 相似文献
996.
The purpose of this study was to examine social context processing in persons with schizophrenia. A secondary goal was to examine the ecological validity of these measures (i.e. how they relate to social behavior in the treatment setting). The performance of 35 persons with DSM-IV diagnosed schizophrenia and/or schizoaffective disorder was compared to a non-clinical control sample of 46 individuals on a battery of social perceptual tasks that require social context processing. In addition, the relationship between social context processing and ward behavior (as measured with the Nurse's Observation Scale for Inpatient Evaluation) was examined for the clinical sample only. The results showed that the group with schizophrenia/schizoaffective disorder was impaired on all tasks relative to the control group and showed little evidence of utilizing available contextual information. Task performance for the group with schizophrenia/schizoaffective disorder was relatively independent of symptoms, but was related to social functioning in the treatment setting. Implications for future research are discussed. 相似文献
997.
998.
999.
High-throughput screening for evidence of association by using mass spectrometry genotyping on DNA pools 总被引:9,自引:0,他引:9
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Mohlke KL Erdos MR Scott LJ Fingerlin TE Jackson AU Silander K Hollstein P Boehnke M Collins FS 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(26):16928-16933
To facilitate positional cloning of complex trait susceptibility loci, we are investigating methods to reduce the effort required to identify trait-associated alleles. We examined primer extension analysis by matrix-assisted laser desorptionionization time-of-flight mass spectrometry to screen single-nucleotide polymorphisms (SNPs) for association by using DNA pools. We tested whether this method can accurately estimate allele frequency differences between pools while maintaining the high-throughput nature of assay design, sample handling, and scoring. We follow up interesting allele frequency differences in pools by genotyping individuals. We tested DNA pools of 182, 228, and 499 individuals using 16 SNPs with minor allele frequencies 0.026-0.486 and allele frequency differences 0.001-0.108 that we had genotyped previously on individuals and 381 SNPs that we had not. Precision, as measured by the average standard deviation among 16 semidependent replicates, was 0.021 +/- 0.011 for the 16 SNPs and 0.018 +/- 0.008 for the 291381 SNPs used in further analysis. For the 16 SNPs, the average absolute error in predicting allele frequency differences between pools was 0.009; the largest errors were 0.031, 0.028, and 0.027. We determined that compensating for unequal peak heights in heterozygotes improved precision of allele frequency estimates but had only a very minor effect on accuracy of allele frequency differences between pools. Based on these data and assuming pools of 500 individuals, we conclude that at significance level 0.05 we would have 95% (82%) power to detect population allele frequency differences of 0.07 for control allele frequencies of 0.10 (0.50). 相似文献
1000.
Andres E Ruellan A Pflumio F Goichot B Imler M Schlienger JL 《European Journal of Internal Medicine》2002,13(2):136-138
Our aim was to compare the sensitivity of various diagnostic criteria for adult Still's disease in 17 patients with established adult Still's disease who were followed in a department of internal medicine over a mean period of 7 years. The median age of the 17 patients was 27 years and the sex ratio M:F was 1:4. The patients had essentially systemic manifestations with fever (n=14), inflammation and leukocytosis (n=16), and moderate liver dysfunction (n=13) that disappeared after a mean of 21 days (range 8-48 days). In the first week of hospitalization, the sensitivities of the criteria proposed by Yamaguchi, Reginato, and Kahn were 94, 18, and 23%, respectively. One month later, the sensitivity was 100% for Yamaguchi's diagnostic criteria versus only 88% for Reginato's and Kahn's criteria. This study confirms that Yamaguchi's diagnostic criteria are more sensitive and are met earlier than Reginato's and Kahn's criteria in patients followed in internal medicine. 相似文献