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131.
TC Ryan WW Cruikshank H Kornfeld TL Collins DM Center 《Canadian Metallurgical Quarterly》1995,270(29):17081-17086
Lymphocyte chemoattractant factor (LCF) is a polypeptide cytokine which induces both cell motility and activation of T lymphocytes. These LCF-induced events demonstrate an absolute requirement for the cell surface expression of CD4. Because many CD4-mediated T lymphocyte activation events have been demonstrated to require the association of the src-related tyrosine kinase p56lck with the cytoplasmic domain of CD4, we examined the role of p56lck in LCF-induced lymphocyte migration in a murine T cell hybridoma line expressing transfected human CD4. LCF induces the catalytic activity of CD4 associated p56lck at chemoattractant concentrations of cytokine. Hybridoma cells that express CD4 with cytoplasmic point mutations which uncouple the CD4-lck association lack both lck enzymatic activity and chemotactic responses to LCF. The enzymatic activity of lck however does not appear to be required for CD4-mediated migratory signal. First, the protein tyrosine kinase inhibitor herbimycin A blocked LCF-induced p56lck activation but had no effect on the LCF-induced motile response. Second, T cell hybridomas expressing a chimeric receptor combining the extracellular domain of human CD4 and murine p56lck which lacked the kinase domain had a normal LCF-induced motile response. We conclude from these observations that CD4-lck coupling is essential for LCF-induced T lymphocyte migration but the motile response is independent of the enzymatic activity of CD4-associated p56lck. 相似文献
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133.
JB Vermorken A Kobierska ME van der Burg B Chevallier F Zanaboni WW ten Bokkel Huinink M Forni A Pawinski E van der Putten G Bolis 《Canadian Metallurgical Quarterly》1995,16(6):433-438
A follow up study of 20 cases of renal cell carcinoma with regional lymph node metastasis at the department of urology in Niigata Cancer Center Hospital from 1979 to 1993 is presented. During this period, we treated 249 patients with renal cell carcinoma with or without lymph node metastasis. Lymph node metastasis could be estimated in 188 out of 249 patients. Histologically, lymph node metastasis was classified as pN1 in 8 cases, pN2 in 7 cases, and pN3 in 5 cases. The 3- and 5-year survival rates of 20 patients with lymph node metastasis were 45.0% and 16.4%, respectively. Nine of the 20 cases had no distant metastasis and 11 cases had distant metastasis. Three of the 9 patients with distant metastasis had no recurrence. Two of these 3 patients are still alive after 10 years and 3 years and 1 patient died because of acute heart failure. These 3 patients had pN1 metastasis smaller than 1 cm lymph node. Four of the 11 patients with distant metastasis had more than a two-year survival. However, 3 patients died due to renal cell carcinoma although primary and metastatic regions were resected and IFN with chemotherapy were given. Only one patient is still alive without recurrence after 3 years. This case detected as right renal cell carcinoma with pN2 metastasis and bilateral pulmonary metastasis was treated with radical nephrectomy with regional lymph node dissection and administered Methotrexate, VP16 and CisPlatinum chemotherapy and IFN.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
134.
By homology to the mgt gene (encoding a macrolide glycosyltransferase) from Streptomyces lividans, a 3.3-kb DNA fragment from the oleandomycin producer, Streptomyces antibioticus, was cloned and sequenced. Analysis of the sequence revealed the presence of the 3' end of a gene (ORF1) and two complete ORFs (ORF2 and oleD), all of them translationally coupled. The deduced product of the sequenced region of ORF1 contained the typical signature of integral membrane proteins responsible for the translocation of substrates across the membrane. The ORF2 product did not show significant similarity with proteins in databases, but contains an N-terminus leader peptide region characteristic of secreted proteins, and a lipid attachment site motif characteristic of membrane lipoproteins synthesized with a precursor signal peptide. The oleD product showed clear similarity with several UDP-glucuronosyl- and UDP-glycosyl-transferases from different origins and particularly with the mgt gene from S. lividans, and might encode a glycosyltransferase activity capable of inactivating macrolides. It is proposed that these three genes could participate in the intracellular glycosylation of oleandomycin and its secretion during antibiotic production. 相似文献
135.
HR Franklin GP Simonetti AC Dubbelman WW ten Bokkel Huinink BG Taal G Wigbout IA Mandjes OB Dalesio NK Aaronson 《Canadian Metallurgical Quarterly》1994,5(2):113-117
Human neutrophil PLD activity stimulated with GTP-gamma-S was reconstituted with recombinant ARF1 in cytosol-depleted cells. PMA-pretreatment of intact cells greatly enhanced the subsequent reconstitution of the ARF1-regulated PLD activity. This enhancement was only observed provided that the intact cells were pretreated with PMA, suggesting the stable recruitment of a cytosolic component, presumably protein kinase C, to the membranes. rARF1-reconstituted PLD activity was not dependent on MgATP, but could be considerably enhanced by MgATP. Maximal effects of MgATP were seen at 1 mM. This enhancement by MgATP could not be attributed to protein kinase C. Neomycin was found to inhibit ARF1-regulated PLD activity suggesting the requirement for polyphosphoinositides. We conclude: (i) that many of the observed effects of PMA may be dependent on the presence of the small GTP-binding protein, ARF, and (ii) polyphosphoinositides are required for ARF1-stimulated PLD activity. 相似文献
136.
137.
WW Menninger 《Canadian Metallurgical Quarterly》1993,57(2):208-217
Violence is the ultimate maladaptive coping behavior manifested by a small but significant number of psychiatric patients. The management of the aggressive and dangerous patient depends on recognition of predisposing developmental experiences, cognitive and behavioral factors, and situational circumstances that potentiate a violent outburst. The author presents management guidelines, which stem from an understanding of the paranoid process, respect for the limited coping skills of the individual, and appropriate use of verbal, physical, and chemical interventions. 相似文献
138.
MP Thomas WW Webster RB Norgren DT Monaghan RA Morrisett 《Canadian Metallurgical Quarterly》1998,85(2):615-626
An important general question in neurobiology concerns the development and expression of the rich context of neuronal phenotypes, especially in relation to the diverse patterns of connectivity. Organotypic cultures of brain slices may offer distinct advantages for such studies if such a preparation survives, maintains a wide diversity of neuronal phenotypes and displays appropriate synaptic connections between regions. To address these requirements, we utilized long-term organotypic cultures of intact horizontal slices of rat forebrain and midbrain and assessed a variety of markers of phenotype in combination with functional tests of connectivity. This explant preparation displayed a distinct viability requirement such that the greatest explant survival was seen in slices taken from pups of less than postnatal day 7 and was independent of N-methyl-D-aspartate channel blockade. The anatomical features of the major brain regions (e.g., neocortex, striatum, septum, hippocampus, diencephalon and midbrain) were observed in their normal boundaries. The presence of cholinergic and catecholaminergic neurons was demonstrated with acetylcholinesterase histochemistry and tyrosine hydroxylase immunohistochemistry. Labelled neurons displayed multiple, regionally-appropriate cytoarchitectures and, in some cases, could be seen to project to brain regions in a manner quite similar to that seen in vivo. Finally, the direct demonstration of spontaneous and evoked interregional excitatory synaptic transmission was made using whole-cell patch-clamp recordings from striatal neurons which revealed an intact glutamate-using corticostriatal pathway. This simple explant preparation appears to contain a rich diversity of neuronal types and synaptic organization. Therefore, this preparation appears to have several distinct advantages for basic neurobiologic research since it combines long-term culture viability and many features of mature brain including complex interregional neuronal systems. 相似文献
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140.
LS Dean M Mickel R Bonan DR Holmes WW O'Neill IF Palacios S Rahimtoola JN Slater K Davis JW Kennedy 《Canadian Metallurgical Quarterly》1996,28(6):1452-1457
OBJECTIVES: This study reports the long-term outcome of patients undergoing percutaneous balloon mitral commissurotomy who were enrolled in the National Heart, Lung, and Blood Institute (NHLBI) Balloon Valvuloplasty Registry. BACKGROUND: The NHLBI established the multicenter Balloon Valvuloplasty Registry in November 1987 to assess both short- and long-term safety and efficiency of percutaneous balloon mitral commissurotomy. METHODS: Between November 1987 and October 1989, 736 patients > or = 18 years old underwent percutaneous balloon mitral commissurotomy at 23 registry sites in North America. The maximal follow-up period was 5.2 years. RESULTS: The actuarial survival rate was 93 +/- 1% (mean +/- SD), 90 +/- 1.2%, 87 +/- 1.4% and 84 +/- 1.6% at 1, 2, 3 and 4 years, respectively. Eighty percent of the patients were alive and free of mitral surgery or repeat balloon mitral commissurotomy at 1 year. The event-free survival rate was 80 +/- 1.5% at 1 year, 71 +/- 1.7% at 2 years, 66 +/- 1.8% at 3 years and 60 +/- 2.0% at 4 years. Important univariable predictors of actuarial mortality at 4 years included age > 70 years (51% survival), New York Heart Association functional class IV (41% survival) and baseline echocardiographic score > 12 (24% survival). Multivariable predictors of mortality included functional class IV, higher echocardiographic score and higher postprocedural pulmonary artery systolic and left ventricular end-diastolic pressures (p < 0.01). CONCLUSIONS: Percutaneous balloon mitral commissurotomy has a favorable effect on the hemodynamic variables of mitral stenosis, and long-term follow-up data suggest that it is a viable alternative with respect to surgical commissurotomy in selected patients. 相似文献