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61.
62.
JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
63.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
64.
65.
66.
Alex E. Roher Chera L. Esh Tyler A. Kokjohn Eduardo M. Castaño Gregory D. Van Vickle Walter M. Kalback R. Lyle Patton Dean C. Luehrs Ian D. Daugs Yu-Min Kuo Mark R. Emmerling Holly Soares Joseph F. Quinn Jeffrey Kaye Donald J. Connor Nina B. Silverberg Charles H. Adler James D. Seward Thomas G. Beach Marwan N. Sabbagh 《Alzheimer's & dementia》2009,5(1):18-29
BackgroundWe evaluated the amounts of amyloid beta (Aβ)) peptides in the central nervous system (CNS) and in reservoirs outside the CNS and their potential impact on Aβ plasma levels and Alzheimer's disease (AD) pathology.MethodsAmyloid β levels were measured in (1) the plasma of AD and nondemented (ND) controls in a longitudinal study, (2) the plasma of a cohort of AD patients receiving a cholinesterase inhibitor, and (3) the skeletal muscle, liver, aorta, platelets, leptomeningeal arteries, and in gray and white matter of AD and ND control subjects.ResultsPlasma Aβ levels fluctuated over time and among individuals, suggesting continuous contributions from brain and peripheral tissues and associations with reactive circulating proteins. Arteries with atherosclerosis had larger amounts of Aβ40 than disease-free vessels. Inactivated platelets contained more Aβ peptides than activated ones. Substantially more Aβ was present in liver samples from ND patients. Overall, AD brain and skeletal muscle contained increased levels of Aβ.ConclusionsEfforts to use plasma levels of Aβ peptides as AD biomarkers or disease-staging scales have failed. Peripheral tissues might contribute to both the circulating amyloid pool and AD pathology within the brain and its vasculature. The wide spread of plasma Aβ values is also due in part to the ability of Aβ to bind to a variety of plasma and membrane proteins. Sources outside the CNS must be accounted for because pharmacologic interventions to reduce cerebral amyloid are assessed by monitoring Aβ plasma levels. Furthermore, the long-range impact of Aβ immunotherapy on peripheral Aβ sources should also be considered. 相似文献
67.
A Choppin I Irwin L Lach MG McDonald AE Rettie L Shao C Becker MP Palme X Paliard S Bowersox DM Dennis P Druzgala 《British journal of pharmacology》2009,158(6):1536-1547
Background and purpose:
Tecarfarin (ATI-5923) is a novel vitamin K epoxide reductase inhibitor that is metabolized by esterase (mainly human carboxylesterase 2) to a single major metabolite, ATI-5900, in rats, dogs and humans. Tecarfarin is not significantly metabolized by CYP450 enzymes. The objective of this study was to test and compare the efficacy of tecarfarin with that of warfarin, when administered either intravenously or once a day orally, to produce stable anticoagulation in beagle dogs.Experimental approach:
Effects on coagulation were assessed by measuring the activity levels of Factor VII and Factor X and thromboplastin-induced coagulation times, reported as prothrombin time (PT).Key results:
Continuous intravenous infusions and oral administration of tecarfarin and warfarin caused a dose-dependent decrease in activity of Factor VII and Factor X, and associated increase in PT. Intravenous fresh frozen canine plasma or subcutaneous vitamin K1 treatment reversed the anticoagulant effects of orally administered tecarfarin. Consistent with the inhibitory effects of amiodarone on CYP2C9, co-administration of amiodarone significantly increased the anticoagulation effect of warfarin and plasma warfarin concentrations. In contrast, amiodarone had no effect on the anticoagulation induced by tecarfarin or tecarfarin plasma concentrations in this model.Conclusions and implications:
Overall, the data presented herein indicate that tecarfarin, via a vitamin K-dependent mechanism, causes changes in key parameters of haemostasis in beagle dogs that are consistent with effective anticoagulation. Compared to warfarin it has a decreased potential to interact metabolically with drugs that inhibit CYP450 enzymes and, therefore, may offer an improved safety profile for patients. 相似文献68.
Christine AE Schutgens Merel Schuring Toon AJ Voorham Alex Burdorf 《BMC public health》2009,9(1):197-11
Background
The relationship between poor health and unemployment is well established. Health promotion among unemployed persons may improve their health. The aims of this study were to investigate characteristics of non-participants and drop-outs in a multidisciplinary health promotion programme for long-term unemployed persons with health complaints, to evaluate changes in physical health among participants, and to investigate determinants of improvement in physical health. 相似文献69.
70.
Krutchen AE; Bjarnason H; Stackhouse DJ; Nazarian GK; Magney JE; Hunter DW 《Radiology》1996,200(1):159