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71.
The mechanism of Ara-C-induced apoptosis of differentiating cerebellar granule neurons 总被引:3,自引:0,他引:3
Neurotoxicity is one of the side-effects of the therapeutically useful antitumour agent, Ara-C (or 1-beta-d-arabinofuranosyl-cytosine, cytarabine). This agent is also reported to induce cell death of cultured neurons. In this study, we show that Ara-C-induced death of differentiating rat cerebellar granule neurons is prevented by cycloheximide at concentrations corresponding to its action in preventing protein synthesis. The death is accompanied by cleavage of the caspase substrate poly ADP ribose polymerase (PARP) and c-Abl-dependent activation of the stress-activated protein kinases c-Jun N-terminal kinase and p38. However, c-Jun levels do not rise and the activation of the stress-activated protein kinases is not required for this form of neuronal death. Cyclin-dependent kinase (cdk) activity and inappropriate cell-cycle re-entry have been implicated in some forms of death in differentiated neurons. Here we show that Ara-C-induced death of cerebellar granule neurons is prevented by an inhibitor of cdk4, whereas inhibition of cdk1, -2 and -5 mimics the death, and non-cdk4/6 cdks are inhibited by Ara-C treatment. Cdk1 and -2 are dramatically down-regulated during neuronal differentiation, and neither Ara-C nor inhibition of these cdks induces death in mature neurons. This mechanism could also play a significant role in the neurotoxicity associated with the therapeutic use of Ara-C, as cdk levels can be upregulated in stressed neurons of adult brain. We propose that the balance between cdk4/6 and cdk1/2/5 activity may determine the survival of early differentiating neurons, and that DNA-damaging agents may induce neuronal death by inhibiting cdk1/2/5 under conditions which require these activities for survival. 相似文献
72.
Mijch AM Judd FK Lyketsos CG Ellen S Cockram A 《The Journal of neuropsychiatry and clinical neurosciences》1999,11(4):475-480
A case-control study of 19 patients with HIV-associated mania and 57 HIV-seropositive control patients matched by CD4 cell count, age, and year of treatment was undertaken to investigate associations with risk factors for human immunodeficiency virus (HIV) infection, treatment, and disease. There was no significant difference between groups for HIV exposure category, baseline health status, or drugs other than antiretrovirals. Zidovudine therapy provided a significant protective effect against the development of mania, whether administered at or prior to diagnosis of mania. In a 3-year follow-up study, incident AIDS dementia was significantly more common in patients with mania, despite no apparent difference in survival between cases and controls. These findings strengthen the evidence of an etiological association of HIV neuropathology with AIDS mania by demonstrating a protective effect of an antiretroviral agent able to penetrate the central nervous system. 相似文献
73.
Data are presented from a screening study of ambulant attendees at two London Accident and Emergency (A&E) departments. Among young people (aged 16-24 years), 37.2% were drinking harmfully [an Alcohol-Use Disorders Identification Test (AUDIT) score of 8 or more]; 17.3% admitted to drinking alcohol in the 6 h prior to attendance; and 14.6% considered that their attendance was alcohol related. Young women were as likely as men to score 8 or over. This age group had nearly twice the odds of scoring highly on the AUDIT, compared to those over 25 years old, and were more likely to report that their attendance was alcohol related. Screening in A&E departments would identify considerable numbers of young people who might benefit from brief intervention, but the problems of doing so are acknowledged. 相似文献
74.
Judd W. Moul Richard K. Dodge Judith E. Robertson David F. Paulson Philip J. Walther 《World journal of urology》1991,9(1):45-50
Summary The records of all testicular cancer patients evaluated and treated at our medical center during two consecutive 9-year periods were reviewed and analyzed for prognostic factors, particularly the impact of cisplatin-based combination chemotherapy. The data base of 244 patients was divided into two eras: 1970–1978, defined as the pre-cisplatin era (n=101) and 1979–1987, the cisplatin era (n=143). Statistically improved survival (P=0.024) was noted for the 165 nonseminoma patients and for a grouping of 143 patients treated with combination chemotherapy (P=0.004) during the cisplatin era. Stratification by stage revealed that stage II patients had the most significant survival advantage (P=0.001) during the cisplatin era; cancer mortality improved from 48% to 9%. Cancer death rates for stage III patients decreased from 58% to 39% which is clinically but not statistically significant (P=0.497). Stage I patients and the seminoma population did well during both eras, and the impact of cisplatin could not be statistically confirmed in this study for these subgroups. Multivariate statistical analysis confirmed the importance of the era of treatment for the nonseminoma population. 相似文献
75.
76.
Psychosocial disability during the long-term course of unipolar major depressive disorder 总被引:4,自引:0,他引:4
Judd LL Akiskal HS Zeller PJ Paulus M Leon AC Maser JD Endicott J Coryell W Kunovac JL Mueller TI Rice JP Keller MB 《Archives of general psychiatry》2000,57(4):375-380
BACKGROUND: The goal of this study was to investigate psychosocial disability in relation to depressive symptom severity during the long-term course of unipolar major depressive disorder (MDD). METHODS: Monthly ratings of impairment in major life functions and social relationships were obtained during an average of 10 years' systematic follow-up of 371 patients with unipolar MDD in the National Institute of Mental Health Collaborative Depression Study. Random regression models were used to examine variations in psychosocial functioning associated with 3 levels of depressive symptom severity and the asymptomatic status. RESULTS: A progressive gradient of psychosocial impairment was associated with a parallel gradient in the level of depressive symptom severity, which ranges from asymptomatic to subthreshold depressive symptoms to symptoms at the minor depression/dysthymia level to symptoms at the MDD level. Significant increases in disability occurred with each stepwise increment in depressive symptom severity. CONCLUSIONS: During the long-term course, disability is pervasive and chronic but disappears when patients become asymptomatic. Depressive symptoms at levels of subthreshold depressive symptoms, minor depression/ dysthymia, and MDD represent a continuum of depressive symptom severity in unipolar MDD, each level of which is associated with a significant stepwise increment in psychosocial disability. 相似文献
77.
Holmes AC Judd FK Lloyd JH Dakis J Crampin EF Katsenos S 《The Australian and New Zealand journal of psychiatry》2000,34(3):496-503
OBJECTIVE: The aim of this paper is to describe the development and implementation of clinical indicators in the consultation-liaison service at Royal Melbourne Hospital (RMH). METHOD: A working party lead by the University of Melbourne was established in 1998 to develop clinical indicators and a database for the RMH consultation-liaison service. Core parameters for measuring service functioning and six clinical indicators were developed. The system was implemented using a data collection form and computerised database operating within a system of regular clinical reviews. RESULTS: The clinical indicators, database and review system were found to be a feasible, useful and efficient addition to a consultation-liaison service at a major general hospital. CONCLUSIONS: Clinical indicators may be used within specialist psychiatry services to enhance clinical care and aid in service development and teaching. 相似文献
78.
Leon AC Solomon DA Mueller TI Endicott J Posternak M Judd LL Schettler PJ Akiskal HS Keller MB 《The Journal of nervous and mental disease》2000,188(12):805-812
Those afflicted with bipolar disorder often suffer from substantial functional impairment both when in episode and when in remission. This study examined the psychometric properties of a brief assessment of psychosocial functioning, the Range of Impaired Functioning Tool (LIFE-RIFT), among subjects with bipolar I disorder. The study sample consisted of 163 subjects who presented with bipolar I disorder at intake into the NIMH Collaborative Depression Study (CDS). All LIFE-RIFT items come from the Longitudinal Interval Follow-up Evaluation (LIFE). Follow-up data that were used to examine the reliability and validity of the scale come from assessments of psychosocial functioning that were conducted 6, 12, 18, and 24 months after intake into the CDS. The results of factor analyses indicate that the scale items are measures of one construct, psychosocial functioning. The interrater agreement on the scale score was very good with an intraclass correlation coefficient was 0.94. The internal consistency reliability among the scale items was uniformly satisfactory over the four assessment periods, with coefficient alpha ranging from 0.78 to 0.84. Mixed-effect regression analyses showed that during mood episodes subjects were significantly more impaired than those in recovery. In conclusion, the psychometric properties of the LIFE-RIFT were examined in subjects with bipolar I disorder. The analyses from this longitudinal, observational study provide empirical support for the reliability and validity of the scale. The LIFE-RIFT provides a brief, inexpensive alternative to scales currently used to assess psychosocial functioning and can be easily added to semistructured assessments that are used in clinical and treatment outcome studies. 相似文献
79.
Effect of a cognitive behavioral intervention on reducing symptom severity during chemotherapy. 总被引:4,自引:0,他引:4
Charles Given Barbara Given Mohammad Rahbar Sangchoon Jeon Ruth McCorkle Bernadine Cimprich Andrzej Galecki Sharon Kozachik Albert Brady Mary Jo Fisher-Malloy Kathy Courtney Elizabeth Bowie 《Journal of clinical oncology》2004,22(3):507-516
PURPOSE: To describe a randomized trial of a cognitive behavioral intervention on reducing symptom severity among patients diagnosed with solid tumors and undergoing a first course of chemotherapy and to determine whether the intervention had an additive or interactive effect on symptom severity in the presence of supportive care medications. PATIENTS AND METHODS: Patients (N = 237) were accrued from comprehensive and community cancer centers, interviewed, and randomly assigned to either the experimental intervention (n = 118) or conventional care (n = 119). A symptom severity index, based on summed severity scores across 15 symptoms, was the primary outcome. Each patient's site of cancer, stage at diagnosis, chemotherapy protocols, and use of supportive medications were learned from medical records. RESULTS: Groups were equivalent at baseline, and attrition by characteristics by group was not different. The proportion of patients not receiving chemotherapy at 10 and 20 weeks did not differ by group. At the 10- and 20-week observations, there was a significant interaction between the experimental group and baseline symptom severity. Patients in the experimental group who entered the trial with higher symptom severity reported significantly lower severity at 10 and 20 weeks. Controlling for chemotherapy treatment status at follow-up and supportive care medications did not alter the effect of the experimental intervention. CONCLUSION: Compared with conventional care alone, the experimental intervention was effective among patients who entered the trial with higher levels of symptom severity. Age, sex, site or stage of cancer, and supportive medications did not modify the effect of this cognitive behavioral intervention on symptom severity. 相似文献
80.