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101.
A number of cellular proteins have been identified as caspase targets during cell death, including the PITSLRE protein kinases. These targets generally fall into one of three possible categories: 1) other caspases, 2) proteins that are inactivated during apoptosis, and 3) proteins that are required for execution of the cell death program. However, not all proteins are cleaved by caspases during apoptosis. Why only specific proteins are destined to be processed by caspases during cell death is currently not clear. Here we show that multiple caspase-like activities are involved in the processing of the PITSLRE p110 isoforms during Fas-induced apoptosis in Jurkat T-cells. Three p110 caspase cleavage sites have been mapped to the amino-terminal domain of p110 and verified by site-directed mutagenesis. Curiously, the mutagenesis studies revealed that cleavage of two juxtaposed caspase sites is necessary for the complete processing of this protein during cell death in vivo. Finally, we demonstrate that the PITSLRE p110 protein is rapidly phosphorylated during Fas-induced apoptosis in Jurkat cells and that phosphorylation of an amino-terminal portion of the protein may enhance caspase cleavage in this region. 相似文献
102.
AM O''Connor ER Drake VJ Fiset J Page D Curtin HA Llewellyn-Thomas 《Canadian Metallurgical Quarterly》1997,29(3):113-120
As the size of the older population grows and mortality rates continue to decline, an unprecedented number of women will live to very old age. Recent research has provided a better understanding of the impact of disability in the older population, risk factors for disability, and the consequences of disability. Older women have consistently been found to have higher prevalence rates of disability than men of the same age. This difference does not result from women developing disability more often than men, but rather surviving longer with their disabilities. This effect may be explained at least in part by the differences in the diseases underlying disability in older women and men. Interventions that can reduce the burden of disability in the aging population are now being explored. In the next century, it will be increasingly important to develop new prevention and treatment strategies that address the functional consequences of chronic disease in the population of women living to older and older ages. 相似文献
103.
104.
AM Stoppa R Bouabdallah C Chabannon G Novakovitch N Vey J Camerlo D Blaise L Xerri M Resbeut D Di Stefano VJ Bardou JA Gastaut D Maraninchi 《Canadian Metallurgical Quarterly》1997,15(5):1722-1729
PURPOSE: To demonstrate the feasibility and efficacy of six ambulatory high-dose sequential chemotherapy courses that include three intensified cycles supported by stem-cell infusion in high-risk and high-intermediate-risk untreated non-Hodgkin's lymphoma (NHL) patients. PATIENTS AND METHODS: A pilot nonrandomized study included 20 untreated patients aged less than 60 years with aggressive histologically identified NHL and two or three adverse-prognosis criteria (International Index). Patients received an ambulatory regimen with high-dose chemotherapy supported by granulocyte colony-stimulating factor (G-CSF) and repeated peripheral-blood stem-cell (PBSC) infusion. The median age was 39 years (range, 20 to 59), with 13 men and seven women. Chemotherapy consisted of one cycle every 21 days for a total of six cycles. The first three cycles (A1, A2, and A3) consisted of cyclophosphamide (Cy) 3,000 mg/m2, doxorubicin (Doxo) 75 mg/m2, and vincristine 2 mg (plus corticosteroids). The last three cycles (B4, B5, and B6) consisted of the same drug combination plus etoposide 300 mg/m2 and cisplatin 100 mg/m2. For an expected duration of 18 weeks, the projected dose-intensity was 25 mg/m2/wk for Doxo and 1,000 mg/m2/wk for Cy. G-CSF 300 micrograms was administered from day 6 following each cycle until neutrophil reconstitution. Two aphereses were performed at approximately day 13 after each A cycle, and PBSCs were injected at day 4 of each B cycle. Radiotherapy on tumor masses > or = 5 cm was scheduled after completion of the last cycle. RESULTS: The median duration of grade 4 neutropenia was 1 day (range, 0 to 7) for each A cycle and 4 days (range, 1 to 10) for each B cycle (P = .02). The median duration of grade 4 thrombopenia was 0 days (range, 0 to 8) for each A cycle and 6 days (range, 1 to 21) for each B cycle (P < .001). Hospitalization for febrile neutropenia was required for 18% and 44% of patients during cycles A and B, respectively (P < .01). Only three patients did not complete the protocol: one due to emergency surgery after cycle B4, one who died after cycle B5 from interstitial pneumonia, and one with delayed hematologic reconstitution after cycle B4. Chemotherapy delivery was optimal (median actual relative dose-intensity, 97%; range, 66 to 100). The median total dose administered over 18 weeks was 18,000 mg Cy (range, 12,000 to 18,000), 450 mg Doxo (range, 300 to 450), 900 mg etoposide (range, 300 to 900), and 300 mg cisplatin (range, 100 to 300). Evaluation of response after six courses showed 13 complete remissions ([CRs] 65%), four partial remissions (PRs), two nonresponses (NRs), and one toxic death. With a median follow-up period of 25 months (range, 16 to 43), 15 patients are alive, with 12 in continuous first CR; five patients relapsed (four of four PRs and one of 13 CRs). Two-year survival and failure-free survival (FFS) rates are 73% and 56%, respectively. The disease-free survival (DFS) rate for the CRs is 86%. CONCLUSION: PBSC support contributes to the feasibility of first-line, very-high-dose, ambulatory chemotherapy delivery in poor-risk NHL and is associated with a high rate of remission and FFS. 相似文献
105.
Illumination with solid state lighting technology 总被引:13,自引:0,他引:13
Steigerwald D.A. Bhat J.C. Collins D. Fletcher R.M. Holcomb M.O. Ludowise M.J. Martin P.S. Rudaz S.L. 《IEEE journal of selected topics in quantum electronics》2002,8(2):310-320
High-power light-emitting diodes (LEDs) have begun to differentiate themselves from their more common cousins the indicator LED. Today these LEDs are designed to generate 10-100 lm per LED with efficiencies that surpass incandescent and halogen bulbs. After a summary of the motivation for the development of the high-power LED and a look at the future markets, we describe the current state of high-power LED technology and the challenges that lay ahead for development of a true "solid state lamp." We demonstrate record performance and reliability for high-power colored and white LEDs and show results from the worlds first 100-plus lumen white LED lamp, the solid state equivalent of Thomas Edison's 20-W incandescent lightbulb approximately one century later 相似文献
106.
Dr. Remya Rajan Dr. Dirk Schepmann Ruben Steigerwald Dr. Julian A. Schreiber Dr. Ehab El-Awaad Prof. Joachim Jose Prof. Guiscard Seebohm Prof. Bernhard Wünsch 《ChemMedChem》2021,16(20):3201-3209
Recent studies have shown the involvement of GluN2A subunit-containing NMDA receptors in various neurological and pathological disorders. In the X-ray crystal structure, TCN-201 ( 1 ) and analogous pyrazine derivatives 2 and 3 adopt a U-shape (hairpin) conformation within the binding site formed by the ligand binding domains of the GluN1 and GluN2A subunits. In order to mimic the resulting π/π-interactions of two aromatic rings in the binding site, a [2.2]paracyclophane system was designed to lock these aromatic rings in a parallel orientation. Acylation of [2.2]paracyclophane ( 5 ) with oxalyl chloride and chloroacetyl chloride and subsequent transformations led to the oxalamide 7 , triazole 10 and benzamides 12 . The GluN2A inhibitory activities of the paracyclophane derivatives were tested with two-electrode voltage clamp electrophysiology using Xenopus laevis oocytes expressing selectively functional NMDA receptors with GluN2A subunit. The o-iodobenzamide 12 b with the highest similarity to TCN-201 showed the highest GuN2A inhibitory activity of this series of compounds. At a concentration of 10 μM, 12 b reached 36 % of the inhibitory activity of TCN-201 ( 1 ). This result indicates that the [2.2]paracyclophane system is well accepted by the TCN-201 binding site. 相似文献
107.
P Jarho K J?rvinen A Urtti VJ Stella T J?rvinen 《Canadian Metallurgical Quarterly》1996,48(3):263-269
The complexation of pilocarpine prodrug, O,O'-dipropionyl-(1,4-xylylene) bispilocarpate, with various beta-cyclodextrin (beta-CyD) derivatives was studied by the phase solubility method. The effects of coadministered sulphobutyl ether beta-CyD (SBE7-beta-CyD) with and without poly(vinyl alcohol) (PVA) on the miotic response and eye irritation of the prodrug were investigated in pigmented rabbits. The pilocarpine prodrug formed 1:1 inclusion complexes with variably substituted sulphobutyl ether derivatives of beta-CyD (SBE4-beta-CyD and SBE7-beta-CyD), and 1:1 and 1:2 complexes with hydroxypropyl-beta-CyD (HP-beta-CyD) at pH 7-4. Coadministered SBE7-beta-CyD eliminated the eye irritation due to the pilocarpine prodrug, but also decreased the miotic response. Ocular absorption of the prodrug was improved by increasing the viscosity of prodrug/SBE7-beta-CyD solution with PVA without inducing any eye irritation. Eye irritation due to viscous prodrug/SBE7-beta-CyD solutions was comparable with isotonic NaCl solution. We conclude that administration of pilocarpine prodrug in viscous SBE7-beta-CyD solution decreases substantially eye irritation while ocular absorption is not affected. 相似文献
108.
LW Dickerson DJ Rodak TJ Fleming PJ Gatti VJ Massari JC McKenzie RA Gillis 《Canadian Metallurgical Quarterly》1998,70(1-2):129-141
The present study examined the performance of rats with neurotoxic lesions centred in the thalamic nucleus medialis dorsalis on standard and modified versions of the eight arm radial maze test. In Experiment 1, the thalamic lesions produced a borderline deficit in acquisition of the standard task, but subsequently had no effect when a delay was interposed after the first four arms had been entered. The same lesions had no effect on T-maze alternation, but they did impair radial-arm maze performance when intramaze and extramaze cues were set against each other. In Experiment 2, lesions of the dorsomedial thalamus impaired acquisition of the standard radial-arm maze task, but combining the results from Experiments 1 and 2 showed that this acquisition deficit was confined to those animals in which bilateral damage extended into the adjacent anterior thalamic nuclei. In addition, lesions of the dorsomedial thalamus disrupted radial-arm maze performance when the task was modified to compare working memory and reference memory and increased activity and exploration. These changes were not associated with anterior thalamic damage. Finally, the thalamic lesions did not affect performance on a test of spontaneous object recognition. It is concluded that lesions of medialis dorsalis do not disrupt spatial memory but do affect other processes that can interact with task performance. These include a failure of extramaze cues to overshadow intramaze cues, a change in activity and exploration levels and deficits in with-holding spatial responses. 相似文献
109.
Three hundred and one clinical medical students in four universities took the same 50 question MCQ dermatology examination after their dermatology teaching. In one centre, half the students had had additional teaching; these students performed better (mean score 47.5%, n = 29) than those who had no extra teaching (mean score 40.9%, n = 29). In another centre, the students' mean score improved from 24.1 (SD = 6.7) before to 41.6 (SD = 7) (n = 46, P < 0.001) after their dermatology teaching. The different subject areas covered by the examination were analysed separately. In the lowest scoring centre (mean score 34.0, SD = 9.4) the students scored lowest in 9 of the 14 subject areas. In the highest scoring centre (mean score 47.5, SD = 9.9) students scored highest in 7 of these 14 subject areas. This study enabled questions of high discriminatory value to be identified for future use. The use of the same examination in different centres provides feedback for the centres concerning strengths and weaknesses of their teaching. 相似文献
110.
AB Mulder NR Blom JW Smit MH Ruiters J van der Meer MR Halie VJ Bom 《Canadian Metallurgical Quarterly》1995,80(5):399-411
A discrepancy exists between basal tissue factor (TF) expression found in endothelial cell cultures and the failure to detect TF in unpertubated endothelial cells in vivo. We demonstrated that basal TF expression in endothelial cell cultures originated from contaminating cells. These cells were ultrastructurally and flowcytometrically identified as smooth muscle cells. The cell cultures had been obtained from collagenase-treated human umbilical cord vessels. Histologic studies revealed that after collagenase treatment the basement membrane was digested and underlying structures were disrupted at some areas of the vein. We selected chymotrypsin as an alternative for the isolation of endothelial cells. Using chymotrypsin, the endothelial lining was selectively lost leaving the basement membrane undisturbed. Furthermore, use of chymotrypsin instead of collagenase minimized the level of basal TF activity. Taken together, we demonstrated that basal TF expression in endothelial cell cultures is caused by contaminating smooth muscle cells. This contamination can strongly be reduced using chymotrypsin instead of collagenase for isolation of endothelial cells. 相似文献