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981.
SJ Hedley DJ Gawkrodger AP Weetman R Morandini JM Boeynaems G Ghanem SM Neil 《Canadian Metallurgical Quarterly》1998,138(3):536-543
alpha-Melanocyte stimulating hormone (alpha-MSH) was found significantly to reduce tumour necrosis factor-alpha (TNF-alpha) stimulated upregulation of intercellular adhesion molecule-1 (ICAM-1) in normal adult cutaneous melanocytes. The maximum inhibitory response to alpha-MSH was obtained at around 10(-10) mol/L alpha-MSH when cells were coincubated with alpha-MSH and TNF-alpha for 24 h. alpha-MSH had little or no effect on basal ICAM-1 expression in melanocytes and the effects of alpha-MSH could be mimicked with 3-isobutyl-1-methylxanthine (IBMX). Preliminary data in three human melanoma cell lines also showed alpha-MSH and forskolin to be effective in significantly reducing TNF-alpha stimulated ICAM-1 expression over 24 h. The extent of the inhibition varied from cell line to cell line and was greatest in those cells with the highest number of alpha-MSH receptors. These data suggest that alpha-MSH has the ability to oppose the action of the pro-inflammatory cytokine TNF-alpha on melanocytes and melanoma cells. 相似文献
982.
983.
984.
TH Grayson JM Ellis S Chen RM Graham RD Brown CE Hill 《Canadian Metallurgical Quarterly》1998,293(3):435-444
This article reports results from a meta-analysis on adult age differences in the negative priming effect (21 studies on identity negative priming and 8 on location negative priming). Both younger and older adults were found to be susceptible to the negative priming effect in identity and location tasks. Effect sizes were homogeneous for both tasks, indicating that the data are adequately described without reference to moderator variables. State trace analysis on identity tasks, in which mean latencies in negative priming conditions were regressed onto mean latencies in baseline conditions, showed (a) that in both age groups the negative priming effect is proportional rather than additive and (b) that the negative priming effect is smaller in older adults as compared with younger adults. 相似文献
985.
JM Chabot 《Canadian Metallurgical Quarterly》1998,48(6):651-652
986.
S Roul-Bouriat C Léauté-Labrèze P Bobin JM Tamisier P Vernhes M Geniaux 《Canadian Metallurgical Quarterly》1998,125(12):888-890
BACKGROUND: We report a case of leprosy observed in a French woman who had lived in Africa 30 years earlier. The clinical presentation was misleading, suggesting connective tissue disease. CASE REPORT: A 69-year-old woman was hospitalized in April 1996 for inflammatory joint disease. The first manifestations had developed three years earlier and the patient had been on systemic corticosteroid therapy associated with anti-malarials since 1993. The clinical presentation progressively included neurological and skin manifestations. Histology examination gave the diagnosis of lepromatous leprosy. Three-drug anti-leprosy treatment in one oral dose was initiated. DISCUSSION: Chronic Mycobacterium leprae infection usually leads to overt leprosy with neurological and cutaneous involvement. Rheumatological forms are less common and found almost exclusively during leprous reactions. The association of inflammatory join pain with neurological and skin manifestations wrongly suggested vasculitis. In addition, the general corticosteroid therapy certainly was implicated in disease activation and progression to a purely lepromatous form. 相似文献
987.
TE Goldberg EF Torrey JM Gold LB Bigelow RD Ragland E Taylor DR Weinberger 《Canadian Metallurgical Quarterly》1995,17(1):77-84
We investigated the effect of the adenosine receptor agonist 5'-(N-ethylcarboxamido)adenosine (NECA) in catecholamine secretion from adrenal chromaffin cells that exhibit only the A2b subtype adenosine receptor. NECA reduced catecholamine release evoked by the nicotinic agonist 1,1-dimethyl-4-phenylpiperazinium (DMPP) in a time-dependent manner. Inhibition reached 25% after 30-40-min exposure to NECA. This effect on DMPP-evoked catecholamine secretion was mirrored by a similar (27.7 +/- 3.3%), slowly developing inhibition of [Ca2+]i transients induced by DMPP that peaked at 30-min preincubation with NECA. The capacity of the chromaffin cells to buffer Ca2+ load was not affected by the treatment with NECA. Short-term treatment with NECA failed both to modify [Ca2+]i levels and to increase endogenous diacylglycerol production, showing that NECA does not activate the intracellular Ca2+/protein kinase C signaling pathway. The inhibitory effects of NECA were accompanied by a 30% increase of protein phosphatase activity in chromaffin cell cytosol. We suggest that dephosphorylation of a protein involved in DMPP-evoked Ca2+ influx pathway (e.g., L-type Ca2+ channels) could be the mechanism of the inhibitory action of adenosine receptor stimulation on catecholamine secretion from adrenal chromaffin cells. 相似文献
988.
We have used the technique of cell electrorotation within a microfabricated planar gold electrode array as a means of detecting changes in the physical properties of a single human neutrophil, when activated by the chemotactic factor, phorbol myristate acetate (PMA). The results, which have been analyzed using a double-shell model to represent the cell and its nucleus, provide an indication of the changes in biophysical parameters that occur during cell activation. The methods used in this study have potential applications in the development of single-cell assays for pharmaceutical screening, as a means of determining rapidly the action of drugs. 相似文献
989.
JC Freeburn JM Wallace JJ Strain DG Sinnamon BM Craig D Johnson WS Gilmore 《Canadian Metallurgical Quarterly》1998,102(2):605-608
It is widely recognized that thrombosis is the major event in the evolution of stable vascular disease to unstable ischaemic syndromes including myocardial infarction and stroke. The purpose of this case-control study was to establish clinical and laboratory data on the possible relationship between specific components of the haemostatic system and coronary heart disease. The procoagulant activity (PCA) of peripheral monocytes and polymorphonuclear neutrophils was assessed in 21 males who had suffered a myocardial infarction (MI) and in age-matched controls. In addition, total factor VII activity, fibrinogen, tissue factor pathway inhibitor (TFPI). D-dimers, tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1), tumour necrosis factor-alpha (TNF-alpha) and full blood counts were measured. Post MI patients had significantly higher monocyte PCA, higher plasma concentrations of TFPI, fibrinogen, t-PA, T/P100 and also higher total white blood cell and neutrophil counts compared to age-matched controls. This elevated procoagulant state in post MI patients could further exacerbate the disease process and increase the risk of subsequent acute ischaemic events. 相似文献
990.
F Herranz Amo F Camú?ez JM Díez Cordero F Verdú Tartajo E Lledo García G Bueno Chamon 《Canadian Metallurgical Quarterly》1998,51(8):818-820
OBJECTIVE: To describe a case of uretero-iliac fistula, an extremely rare condition that is not easily diagnosed. METHODS/RESULTS: Herein we describe a 76-year-old female who had undergone repeated pelvic surgery for adenocarcinoma of the sigmoid. She had a right ureteral fistula that had been managed conservatively by insertion of a ureteral catheter. Diagnosis was made by selective arteriography of the iliac arteries. The patient was submitted to surgery; primary closure of the arterial fistula and nephroureterectomy were performed. CONCLUSIONS: Uretero-iliac fistula should be suspected in patients with a history of repeated pelvic surgery and ureteral catheter placement that present with massive hematuria. 相似文献