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71.
Maat M Buysse CM Emonts M Spanjaard L Joosten KF de Groot R Hazelzet JA 《Critical care (London, England)》2007,11(5):R112
Background
To gain insight into factors that might affect results of future case-control studies, we performed an analysis of children with sepsis and purpura admitted to the paediatric intensive care unit (PICU) of Erasmus MC-Sophia Children's Hospital (Rotterdam, The Netherlands). 相似文献72.
BACKGROUND: Concern over the theoretical possibility of disease transmission via blood from donors who develop Creutzfeldt-Jakob disease has led to proposals to exclude older individuals from donating plasma for further manufacture into pooled plasma donations. The impact of extending this age-deferral policy to blood donors was examined with respect to the risk for known transmissible viruses. STUDY DESIGN AND METHODS: Demographic characteristics and confirmed prevalence rates (/10(5) first-time donations) and incidence rates (/10(5) person-years for repeat donors) for viral markers were compared for donors < 50 years old (n = 1,259,805 [85%]) and > or = 50 years old (n = 219,856 [15%]) and for donors < 60 years old (n = 1,409,176 [95%]) and > or = 60 years old (n = 70,485 [5%]). Incidence rates were combined with infectious window-period estimates for each virus, to calculate the risk of virus transmission per 10(6) donations. RESULTS: Unadjusted prevalence rates were significantly greater for younger than for older donor groups for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) (p < or = 0.05). Incidence rates (and transmission risk estimates) for HBsAg were significantly higher in the < 50 donor group than in the > or = 50 group (p < or = 0.05), and those for HIV, human T-lymphotropic virus, and HCV were not significantly higher (p > 0.05). Blanket removal of donors over the age of 50 would potentially lead to the following significant increases in the risk of infected units: HIV, 12 percent; HCV, 21 percent; and hepatitis B virus (HBsAg), 22 percent. CONCLUSION: Removal of donors over the age of 60 would not significantly affect the risk of infected units. Deferral of donors > or = 50 years of age from whole-blood donations for unfounded concerns about Creutzfeldt-Jakob disease could have adverse effects on both blood availability and safety. 相似文献
73.
To determine the incidence of transfusion-associated human immunodeficiency virus (HIV) infection after routine screening of donated blood, a pilot study estimated the pretransfusion prevalence of HIV infection among blood product recipients in San Francisco. Among the 911 nonduplicate pretransfusion specimens from recipients without a clinical history of acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC), the overall prevalence of antibody to HIV was 2.9 percent (5.2% among males and 0.6% among females; p = 0.00002). If recipients in specifically defined or possible high-risk groups (n = 348) were excluded, a seropositivity rate of 1.8 percent (10/563) was detected, with all the positives occurring in men (10/242, 4.1%) and none in women (0/321, 0%). This demonstrated prevalence of HIV infection among blood product recipients in San Francisco before transfusion was substantially higher than the known 0.02 to 0.04 percent prevalence in the donor population. Therefore, the population of women without known risk for AIDS is the best in which to assess the risk of HIV infection in patients who are currently receiving seronegative blood transfusions. 相似文献
74.
Sudhakar Selvaraj Osamu Abe Francesco Amico Yuqi Cheng Sean J. Colloby John T. O'Brien Thomas Frodl Ian H. Gotlib Byung-Joo Ham M Justin Kim P Cédric MP Koolschijn Cintia A.‐M. Périco Giacomo Salvadore Alan J. Thomas Marie‐José Van Tol Nic J.A. van der Wee Dick J. Veltman Gerd Wagner Andrew M. McIntosh 《Human brain mapping》2016,37(4):1393-1404
75.
The inactivation of HIV by gamma-radiation was studied in frozen and liquid plasma; a reduction of the virus titer of 5 to 6 logs was achieved at doses of 5 to 10 Mrad at -80 degrees C and 2.5 Mrad at 15 degrees C. The effect of irradiation on the biologic activity of a number of coagulation factors in plasma and in lyophilized concentrates of factor VIII (FVIII) and prothrombin complex was examined. A recovery of 85 percent of the biologic activity of therapeutic components present in frozen plasma and in lyophilized coagulation factor concentrates was reached at radiation doses as low as 1.5 and 0.5 Mrad, respectively. As derived from the first-order radiation inactivation curves, the radiosensitive target size of HIV was estimated to be 1 to 3 MDa; the target size of FVIII was estimated to be 130 to 160 kDa. Gamma radiation must be disregarded as a method for the sterilization of plasma and plasma-derived products, because of the low reduction of virus infectivity at radiation doses that still give acceptable recovery of biologic activity of plasma components. 相似文献
76.
To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation. 相似文献
77.
MA Vieira-Coelho MP Serr?o J Afonso CE Pinto E Moura 《British journal of pharmacology》2009,158(3):726-737
Background and purpose:
This study investigates the role of α2-adrenoceptor subtypes, α2A, α2B and α2C, on catecholamine synthesis and catabolism in the central nervous system of mice.Experimental approach:
Activities of the main catecholamine synthetic and catabolic enzymes were determined in whole brains obtained from α2A-, α2B- and α2C-adrenoceptor knockout (KO) and C56Bl\7 wild-type (WT) mice.Key results:
Although no significant differences were found in tyrosine hydroxylase activity and expression, brain tissue levels of 3,4-dihydroxyphenylalanine were threefold higher in α2A- and α2C-adrenoceptor KO mice. Brain tissue levels of dopamine and noradrenaline were significantly higher in α2A and α2CKOs compared with WT [WT: 2.8 ± 0.5, 1.1 ± 0.1; α2AKO: 6.9 ± 0.7, 1.9 ± 0.1; α2BKO: 2.3 ± 0.2, 1.0 ± 0.1; α2CKO: 4.6 ± 0.8, 1.5 ± 0.2 nmol·(g tissue)−1, for dopamine and noradrenaline respectively]. Aromatic L-amino acid decarboxylase activity was significantly higher in α2A and α2CKO [WT: 40 ± 1; α2A: 77 ± 2; α2B: 40 ± 1; α2C: 50 ± 1, maximum velocity (Vmax) in nmol·(mg protein)−1·h−1], but no significant differences were found in dopamine β-hydroxylase. Of the catabolic enzymes, catechol-O-methyltransferase enzyme activity was significantly higher in all three α2KO mice [WT: 2.0 ± 0.0; α2A: 2.4 ± 0.1; α2B: 2.2 ± 0.0; α2C: 2.2 ± 0.0 nmol·(mg protein)−1·h−1], but no significant differences were found in monoamine oxidase activity between all α2KOs and WT mice.Conclusions and implications:
In mouse brain, deletion of α2A- or α2C-adrenoceptors increased cerebral aromatic L-amino acid decarboxylase activity and catecholamine tissue levels. Deletion of any α2-adrenoceptor subtypes resulted in increased activity of catechol-O-methyltransferase. Higher 3,4-dihydroxyphenylalanine tissue levels in α2A and α2CKO mice could be explained by increased 3,4-dihydroxyphenylalanine transport. 相似文献78.
Colin S. Hawco Jeffery A. Jones Todd R. Ferretti and Dwayne Keough 《Psychophysiology》2009,46(6):1216-1225
When speakers hear the fundamental frequency (F0) of their voice altered, they shift their F0 in the direction opposite the perturbation. The current study used ERPs to examine sensory processing of short feedback perturbations during an ongoing utterance. In one session, participants produced a vowel at an F0 of their own choosing. In another session, participants matched the F0 of a cue voice. An F0 perturbation of 0, 25, 50, 100, or 200 cents was introduced for 100 ms. A mismatch negativity (MMN) was observed. Differences between sessions were only found for 200-cent perturbations. Reduced compensation when speakers experienced the 200-cent perturbations suggests that this larger perturbation was perceived as externally generated. The presence of an MMN, and no earlier (N100) response suggests that the underlying sensory process used to identify and compensate for errors in mid-utterance may differ from feedback monitoring at utterance onset. 相似文献
79.
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80.
Problematic substance use is associated with depression. Clarifying the relationship between substance use and depression remains an important research goal, with implications for prevention and treatment. Individual differences in the ability to tolerate negative physical and emotional sensations were hypothesized to play a role in substance use behaviors among depressed individuals. The present study investigated the roles of discomfort and distress tolerance in the relationship between alcohol and cannabis problems and depression among undergraduates (N=265). Consistent with other reports, depression was correlated with alcohol and cannabis problems. As predicated, distress tolerance mediated the relationships between depression and alcohol and cannabis problems. Interestingly, discomfort intolerance moderated the relationship between depression and cannabis problems such that depressed individuals with high discomfort tolerance were most vulnerable to cannabis problems. These data suggest that distress intolerance may at least partially account for alcohol and cannabis problems among depressed young adults whereas discomfort intolerance may actually serve a protective role in the development of cannabis problems. 相似文献