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31.
CTLA-4 up-regulation of lymphocyte function-associated antigen 1 adhesion and clustering as an alternate basis for coreceptor function 下载免费PDF全文
Schneider H Valk E da Rocha Dias S Wei B Rudd CE 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(36):12861-12866
Although cytotoxic T lymphocyte antigen-4 (CTLA-4) negatively regulates T cell activation, the full range of functions mediated by this coreceptor has yet to be established. In this study, we report the surprising finding that CTLA-4 engagement by soluble antibody or CD80 potently up-regulates lymphocyte function-associated antigen 1 (LFA-1) adhesion to intercellular adhesion molecule-1 (ICAM-1) and receptor clustering concurrent with IL-2 inhibition. This effect was also observed with CTLA-4 ligation and not with other coreceptors. T cell antigen receptor (TcR)-induced lymphocyte function-associated antigen 1 function was also dependent on CTLA-4 expression as observed with reduced adhesion/clustering on CTLA-4(-/-) primary T cells. CTLA-4 up-regulated adhesion was mediated by regulator for cell adhesion and polarization type 1 (Rap-1) as shown by anti-CTLA-4-induced Rap-1 activation as well as Rap-1-N17 blockade and Rap-1-V12 mimicry of adhesion/clustering. Our findings identify a potent role for CTLA-4 in directing integrin adhesion and provide an alternate mechanism to account for aspects of CTLA-4 function in T cell immunity. 相似文献
32.
Patrick A. Sullivan Helga Gonggrijp Michael J. Crowley J. Barry Ferriss Denis J. O'Sullivan 《Acta diabetologica》1981,18(2):139-146
Summary Plasma angiotensin II concentrations were measured in 14 patients in diabetic ketoacidosis and in two patients with hyperosmolar non-ketotic hyperglycemia, before treatment and again when blood glucose control was restored. In the ketoacidosis group plasma angiotensin II before treatment was markedly raised in all patients with otherwise uncomplicated diabetes, but was within the normal range in some patients with long-term complications such as neuropathy, retinopathy and nephropathy. Mean angiotensin II before treatment was significantly higher in otherwise uncomplicated patients than in those with long-term complications. However, plasma angiotensin II decreased with improved control in all. Angiotensin II levels did not correlate with indices of rehydration such as changes in blood urea, packed cell volume and calculated changes in plasma volume. There was, however, a significant negative association between pretreatment angiotensin II and pH. Two patients with hyperosmolar non-ketotic hyperglycemia were more dehydrated but less acidotic. Pre-treatment angiotensin II in each was well below the mean of the ketoacidosis group. These data are further evidence that the renin-angiotensin system may be impaired in diabetics with long-term complications. In addition, they suggest that factors other than fluid depletion are also important in activating the renin-angiotensin system in uncontrolled diabetes. 相似文献
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Pirlich M Biering H Gerl H Ventz M Schmidt B Ertl S Lochs H 《The Journal of clinical endocrinology and metabolism》2002,87(3):1078-1084
Cushing's syndrome (CS) is associated with low fat-free mass, but it is unclear whether hypercortisolism causes a loss of whole body protein. Body composition was studied prospectively in 15 patients with untreated CS (n = 14 pituitary adenoma; n = 1 adrenal adenoma), in 15 nonobese healthy controls, and in 15 weight-matched obese controls by 3 different methods: total body potassium counting (TBP), bioelectrical impedance analysis (BIA), and anthropometry. In 6 patients, body composition was studied before and within 6 months after pituitary surgery. In CS patients and weight-matched controls, body weight and total body fat were significantly higher than in nonobese controls. In CS patients, TBP was 18.4% lower than predicted, whereas in weight-matched controls TBP was 7.1% higher than predicted. As compared with nonobese and weight-matched controls, in CS patients TBP indicated a significant loss of body cell mass (BCM) of -20.2 and -21.1%, respectively. A significantly reduced arm muscle area of -21.3% compared with weight-matched controls also indicated a loss of whole body protein. In CS, however, BIA overestimated BCM when compared with TBP by +18% and agreement between BIA and TBP in the individual patient was poor (limits of agreement plus minus 27.6%), indicating the invalidity of standard BIA equations in this population. Measurements performed before and 6 months after successful pituitary surgery demonstrated a significant loss of body weight (-11%) and body fat (-33%), but BCM and muscle mass remained on a constant low level. In conclusion, this study shows that, in patients with CS, a significantly reduced BCM indicates a true protein loss. The second interesting finding is that in the early recovery after successful treatment of hypercortisolism patients lose body fat without gaining BCM or muscle mass. 相似文献
34.
Shock wave treatment after hindlimb ischaemia results in increased perfusion and M2 macrophage presence 下载免费PDF全文
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Martin Schmid Helga Prettenthaler Christian Weger Karl-Heinz Smolle 《Computers in biology and medicine》2013,43(10):1583-1589
In mechanically ventilated patients, Pulse Pressure Variation (PPV) has been shown to be a useful parameter to guide fluid management. We evaluated a real-time automated PPV-algorithm by comparing it to manually calculated PPV-values. In 10 critically ill patients, blood pressure was measured invasively (IBP) and non-invasively (CNAP® Monitor, CNSystems Medizintechnik, Austria). PPV was determined manually and compared to automated PPV values: PPVmanIBP vs. PPVautoIBP was ?0.19±1.65% (mean bias±standard deviation), PPVmanCNAP vs. PPVautoCNAP was ?1.02±2.03% and PPVautoCNAP vs. PPVmanIBP was ?2.10±3.14%, suggesting that the automated CNAP® PPV-algorithm works well on both blood pressure waveforms but needs further clinical evaluation. 相似文献
37.
Earlier studies have shown evidence for various sources of observed spousal similarity regarding different traits and characteristics. We explored the relative contribution of non-random mating and convergence to spouse similarity with respect to global mental health, life satisfaction, optimism, and type A personality. We used population-based data collected for the Nord-Trøndelag Health Study (1984–1986) and prospective registry information about when and with whom people entered into marriage/cohabitation between 1970 and 2000 for 19,599 married/cohabitating couples and 1,551 future couples that entered into marriage/cohabitation during the 16 years after data collection. Couples were categorized by interval between data collection and entry into marriage/cohabitation. Age-adjusted polychoric correlations calculated for each group were used as the dependent variables in non-linear, segmented regression analysis, with time since or until marriage/cohabitation as the independent variable. Initial correlations between partners-to-be were low to moderate, typically around one-half of the values estimated in existing couples, indicating both non-random mating and early convergence. There appeared to be moderate divergence during the first 20 years of marriage/cohabitation and moderate convergence during the rest of life. 相似文献
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Kristjansson K Manolescu A Kristinsson A Hardarson T Knudsen H Ingason S Thorleifsson G Frigge ML Kong A Gulcher JR Stefansson K 《Hypertension》2002,39(6):1044-1049
We performed a genomewide scan with 904 microsatellite markers using 120 extended Icelandic families with 490 hypertensive patients. The families were identified by cross-matching a list of hypertensive patients from the Hypertension Clinic of the University Hospital (Landspitalinn) in Iceland with a genealogy database of the entire Icelandic nation. After adding 5 markers, we found linkage to chromosome 18q with an allele-sharing LOD score of 4.60 (P=2.1x 10(-6)). These results provide evidence for a novel susceptibility gene for essential hypertension on chromosome 18q and show that it is possible to study the genetics of essential hypertension without stratifying by subphenotypes. 相似文献