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111.
Alcohol confounds relationship between cannabis misuse and psychosis conversion in a high‐risk sample
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112.
Reliability of an fMRI paradigm for emotional processing in a multisite longitudinal study
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Dylan G. Gee Sarah C. McEwen Jennifer K. Forsyth Kristen M. Haut Carrie E. Bearden Jean Addington Bradley Goodyear Kristin S. Cadenhead Heline Mirzakhanian Barbara A. Cornblatt Doreen Olvet Daniel H. Mathalon Thomas H. McGlashan Diana O. Perkins Aysenil Belger Larry J. Seidman Heidi Thermenos Ming T. Tsuang Theo G.M. van Erp Elaine F. Walker Stephan Hamann Scott W. Woods Todd Constable Tyrone D. Cannon 《Human brain mapping》2015,36(7):2558-2579
Multisite neuroimaging studies can facilitate the investigation of brain‐related changes in many contexts, including patient groups that are relatively rare in the general population. Though multisite studies have characterized the reliability of brain activation during working memory and motor functional magnetic resonance imaging tasks, emotion processing tasks, pertinent to many clinical populations, remain less explored. A traveling participants study was conducted with eight healthy volunteers scanned twice on consecutive days at each of the eight North American Longitudinal Prodrome Study sites. Tests derived from generalizability theory showed excellent reliability in the amygdala ( = 0.82), inferior frontal gyrus (IFG; = 0.83), anterior cingulate cortex (ACC; = 0.76), insula ( = 0.85), and fusiform gyrus ( = 0.91) for maximum activation and fair to excellent reliability in the amygdala ( = 0.44), IFG ( = 0.48), ACC ( = 0.55), insula ( = 0.42), and fusiform gyrus ( = 0.83) for mean activation across sites and test days. For the amygdala, habituation ( = 0.71) was more stable than mean activation. In a second investigation, data from 111 healthy individuals across sites were aggregated in a voxelwise, quantitative meta‐analysis. When compared with a mixed effects model controlling for site, both approaches identified robust activation in regions consistent with expected results based on prior single‐site research. Overall, regions central to emotion processing showed strong reliability in the traveling participants study and robust activation in the aggregation study. These results support the reliability of blood oxygen level‐dependent signal in emotion processing areas across different sites and scanners and may inform future efforts to increase efficiency and enhance knowledge of rare conditions in the population through multisite neuroimaging paradigms. Hum Brain Mapp 36:2558–2579, 2015. © 2015 Wiley Periodicals, Inc . 相似文献
113.
In vivo behavior of human radioiodinated antithrombin III: distribution among three physiologic pools 总被引:3,自引:0,他引:3
It has recently been shown that antithrombin III (AT) distributes between plasma, a noncirculating vascular-associated pool and an extravascular pool in rabbit. Study of the in vivo behavior of autologous human 131I-AT demonstrates that in humans AT also distributes among three pools that are analogous to those found in rabbit. From the in vivo kinetic behavior of the 131I-labeled AT, the fractions of total-body AT in the plasma, noncirculating vascular- associated, and extravascular pools were calculated to be 0.393 +/- 0.015, 0.109 +/- 0.016, and 0.496 +/- 0.014, respectively. From three- exponential plasma radioactivity disappearance curves, an average plasma fractional catabolic rate, j3, of 0.576 +/- 0.034 day-1 was obtained for five healthy young men. This is almost identical to the result obtained if plasma 131I-AT disappearance is assumed to fit a two- exponential curve (0.546 +/- 0.038), where the constant C2 from *Ap(t) = C1e-a1t + C2e-a2t is assumed to be equal to 1 - C1. The fraction of the total vascular AT catabolized daily, j3.5, was calculated to be 0.457 +/- 0.034, and the fractional catabolic rate of total-body AT, jT, averaged 0.2271 +/- 0.0176. The results give further support to a model of in vivo behavior in which the vascular AT distributes between plasma and an endothelial receptor. Thus, the latter may serve to mediate activation of AT for its reaction with coagulation proteases and to mediate its entrance into the endothelial cell, where it is either transported to the extravascular fluids or is catabolized. 相似文献
114.
Restriction endonuclease mapping analyses were made of DNA from a few members of a Macedonian family with hematological characteristics of delta beta-thalassemia, ie, microcytosis, normal HbA2 levels, and elevated levels of HbF (7% to 14%) with G gamma (average 40.5%) and A gamma T chains (average 59.5%). A large deletion of 18 to 23 kb was present with a 5' breakpoint within a 670-bp segment of DNA between the HpaI and NcoI restriction sites 5' to the delta globin gene, and a 3' breakpoint between the BamHI and HpaI restriction sites located some 9 to 13 kb 3' to the beta globin gene. This deletion is different from those present in other types of G gamma A gamma(delta beta)zero- thalassemia. The similarity of the hematological expression of these delta beta-thalassemic conditions which have somewhat comparable 5' breakpoints supports the idea that an important fetal hemoglobin- controlling region lies between the psi beta and delta globin genes. 相似文献
115.
Effect of recombinant granulocyte colony-stimulating factor on neutrophil kinetics in normal young and elderly humans 总被引:15,自引:3,他引:15
Recombinant granulocyte colony-stimulating factor (G-CSF) was administered to healthy young (n = 32) and elderly (n = 19) volunteers (0 microgram/d, 30 microgram/d, or 300 microgram/d) to determine its effect on neutrophil production, blood kinetics, and tissue migration. Measurements included blood counts (daily), marrow neutrophil pool sizes and neutrophil tissue migration (baseline and day 5), blood kinetics (day 6), and marrow transit time while on drug (days 6 to 14). G-CSF markedly expanded the marrow neutrophil mitotic pool and shortened the transit time of the postmitotic pool (control, mean = 6.4 days; 300 microgram/d, mean = 2.9 d). G-CSF increased neutrophil production without significantly altering blood neutrophil half-life or margination. Compared to control, neutrophil accumulation in skin chambers decreased by about 50% in the 300 microgram/d group in both young and elderly subjects. G-CSF induced neutrophilia by stimulating proliferation of marrow neutrophil precursors and accelerating neutrophil entry into the blood. Decreased neutrophil inflammatory responses measured with the skin chamber technique may be because of the relative immaturity of the circulating cells or to alterations in neutrophil phenotype induced by G-CSF. 相似文献
116.
The effectiveness of inhaled corticosteroids in the control of daytime symptoms in asthma is well established, but the specific use against nocturnal asthma has not been systematically studied in Asian patients. This study examined the effect of treatment with inhaled budesonide on the nocturnal variation in measurements of airway calibre, bronchial hyperresponsiveness to inhaled histamine and circulating neutrophil chemotactic activity in Asian patients with nocturnal asthma. Thirty patients, with nocturnal asthma, were randomized into a 2-month, double-blind, parallel group study. Twice as many subjects were allocated to the group who received two consecutive months of inhaled budesonide 1600 μg daily as to the group who received placebo followed by budesonide. Spirometry, lung mechanics, bronchial hyperresponsiveness and serum neutrophil chemotactic factor (NCA) were measured at 16.00 h, 22.00 h and at 04.00 h on 3 days and nights, 4 weeks apart before and after either placebo or budesonide. The combined measurements for the two groups at 04.00 h before and after treatment with budesonide were: forced expiratory volume in 1 s (FEV1) mean (SEM) litres 1.34 (0.17) before, 2.00 (0.19) after; thoracic gas volume (TGV) litres 3.05 (0.32) before, 2.25 (0.14) after; specific airway conductance (sGaw) (cmH20.0 sec)?1 0.39 (0.07) before, 1.16 (0.17) after; PD20μg geometric mean 1.16 before, 44.74 after; neutrophil chemotactic activity (NCA) in units of graduations of migration 98.8 (4.2) before, 101 (14.2) after. The data showed that short and intermediate term high dose inhaled budesonide is an effective specific treatment for nocturnal asthma in Asian patients, resulting in marked improvements in symptoms and in lung mechanics, and reductions in the diurnal variations in bronchial hyperresponsiveness, before any change could be demonstrated in a circulating marker of airway inflammation. 相似文献
117.
Correlation of the biologic effects and binding of cytochalasins to human polymorphonuclear leukocytes 总被引:2,自引:0,他引:2
Treatment of human PMNs with cytochalasins (CE, CD, CB, and H2CB) results in alteration of cell morphology and inhibition of cell motility. Morphological changes are similar to those reported for nonamoeboid fibroblasts--rounding, zeiosis, and arborization. Mean cell velocity of PMNs, as measured by quantitative analysis of time-lapse videotape recordings, was reduced to 0.1 micron/min (control, 7.3 +/- 4.2 micron/min). Phagocytosis by PMNs, as measured by phagocytosis of latex beads, was inhibited by 75%. The relative potency of the cytochalasins for inducing morphological change or for inhibiting locomotion and phagocytosis is similar to their relative potencies for affecting non-amoeboid cells: CE greater than CD greater than CB greater than or equal to H2CB. Quantitative binding of 3H-CB to purified PMNs under equilibrium conditions reveal two types of specific CB binding sites: high-affinity sites (KD approximately 3 x 10(-7) M, 3 x 10(6) sites/cell) and low affinity sites (KD approximately 2 x 10(-6) M). The relative affinities of the cytochalasins for the high-affinity and low-affinity CB binding sites parallel their relative potencies for inducing biologic effects (i.e. CE greater than CD greater than CB greater than or equal to H2CB). 相似文献
118.
Chen YC; Wang CH; Su IJ; Hu CY; Chou MJ; Lee TH; Lin DT; Chung TY; Liu CH; Yang CS 《Blood》1989,74(1):388-394
Among 354 adult patients with either hematological malignancy or aplastic anemia, eight were positive for anti-HTLV-I antibodies; six of eight had received multiple transfusions. There was an approximately 3.5-fold increase (P less than .001) of HTLV-I seropositivity in the patients with hematologic disease (8 of 354, 2.23%) compared to the healthy adults older than 20 years (34 of 5252, .65%). Two hematological patients, one with Hodgkin's disease and one with acute promyelocytic leukemia, were found to be positive for HTLV-I, and developed and died of adult T-cell leukemia/lymphoma (ATL) subsequently. Both were long-term survivors of the primary disease and had received multiple transfusions. The latent period from blood transfusion to onset of ATL was 6 months and 11 years, respectively. Immunocompromised patients, who were seropositive for HTLV-I, may be at increased risk for ATL compared to healthy carriers of HTLV-I, and the latent period may be shorter. 相似文献
119.
Mypinder S. Sekhon Donald E. Griesdale Chiara Robba Nick McGlashan Edward Needham Katherine Walland Alyssa C. Shook Peter Smielewski Marek Czosnyka Arun K. Gupta David K. Menon 《Intensive care medicine》2014,40(9):1267-1274
Purpose
Assess the relationship between optic nerve sheath diameter (ONSD) measured on bedside portable computed tomography (CT) scans and simultaneously measured intracranial pressure (ICP) in patients with severe traumatic brain injury.Methods
Retrospective cohort study of 57 patients admitted between 2009 and 2013. Linear and logistic regression were used to model the correlation and discrimination between ONSD and ICP or intracranial hypertension, respectively.Results
The cohort had a mean age of 40 years (SD 16) and a median admission Glasgow coma score of 7 (IQR 4–10). The between-rater agreement by intraclass coefficient was 0.89 (95 % CI 0.83–0.93, P < 0.001). The mean ONSD was 6.7 mm (SD 0.75) and the mean ICP during CT was 21.3 mmHg (SD 8.4). Using linear regression, there was a strong correlation between ICP and ONSD (r = 0.74, P < 0.001). ONSD had an area under the curve to discriminate elevated ICP (≥20 mmHg vs. <20 mmHg) of 0.83 (95 % CI 0.73–0.94). Using a cutoff of 6.0 mm, ONSD had a sensitivity of 97 %, specificity of 42 %, positive predictive value of 67 %, and a negative predictive value of 92 %. Comparing linear regression models, ONSD was a much stronger predictor of ICP (R 2 of 0.56) compared to other CT features (R 2 of 0.21).Conclusions
Simultaneous measurement of ONSD on CT and ICP were strongly correlated and ONSD was discriminative for intracranial hypertension. ONSD was much more predictive of ICP than other CT features. There was excellent agreement between raters in measuring ONSD. 相似文献120.
CH.U. BRAND TH. HUNZIKER TH. SCHAFFNER A. LIMAT H.A GERBER L.R BRAATHEN 《The British journal of dermatology》1995,132(1):39-45
By means of microsurgical lymph cannulation, skin lymph was sampled in the course of a sodium lauryl sulphate (SLS)-induced irritant contact dermatitis in human volunteers. The lymph cells were isolated by centrifugation, and then characterized immunocytochemically using different monoclonal antibodies, and in the late phase of the skin reaction also by electron microscopy. Analyses of lymph cells before the induction of the contact dermatitis revealed median values of about 60% T cells (CD4/CD8 ratio about 2:1), 4% Langerhans cells (LCs), and 1% B cells. The remainder were varying proportions of erythrocytes and uncharacterized cells. During the skin reaction, and even after resolution of the clinical signs of dermatitis, a relative and absolute increase of T and B cells, as well as of HLA-DR positive cells, paralleled the previously reported increase of LCs; a high percentage of the T cells were CD4 and CD8 negative. In addition, surface markers such as CD11a, CD25, CD54 and CD58 were detected on lymph cells sampled during the irritant skin reaction. Cell rosettes observed in the lymph throughout the experiment were analysed in the late phase of the skin reaction, and showed a central LC with three to five peripheral, in part activated, T cells, ultrastructurally revealing gap junction-like structures between the two cell types. These data indicate that immunocompetent cells in the skin are activated by a variety of non-immunological stimuli such as operative trauma and irritant contact dermatitis. 相似文献