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911.
Perry DK Willingham DL Sibulesky L Bulatao IG Nguyen JH Taner CB 《Annals of hepatology》2011,10(4):482-485
Introduction. Donation after cardiac death (DCD) donors provide an important source of livers that has been used to expand the donor pool. As a consequence of increased numbers of OLT, allograft failure due to early and late complications and disease recurrence are more commonly encountered. The only life saving treatment for patients with liver allograft failure is liver re-transplantation (LR). The use of DCD liver grafts for LR is controversial.Material and methods. Between February 1998 and June 2008, 10 patients underwent LR with DCD allografts. Five (50%) patients had no post operative complications. The 30 day, 1 year, and 3 year patient survival are 80, 60, and 60%, respectively. When DCD grafts are used for sick patients with high MELD scores for LR, the patient and graft survivals are prohibitively low.Conclusion. We do not recommend utilization of DCD liver grafts for LR if a candidate recipient has moderate to high MELD score. 相似文献
912.
Inflated responsibility is increasingly regarded a pathogenetic mechanism in obsessive-compulsive disorder (OCD). In seeming contrast, there is mounting evidence that latent aggression is also elevated in OCD. Building upon psychodynamic theories that an altruistic fa?ade including exaggerated concerns for others is partly a defense against latent aggression, evidence was recently obtained for high interpersonal ambivalence in OCD patients relative to psychiatric and healthy controls using a newly developed instrument entitled the Responsibility and Interpersonal Behaviors and Attitudes Questionnaire (RIBAQ). A total of 46 OCD patients and 23 healthy participants took part in the present study. OCD patients displayed a higher social responsibility than controls. At the same time, patients also disclosed more latent aggression/calculating behavior and interpersonal distrust. While the pathogenic role of latent aggression is still not fully uncovered, it may deserve more consideration in treatment in view of frequent tensions in the families of OCD patients. Longitudinal studies with at-risk sample are needed to assess the relationship between problems with anger expression as well as (exaggerated) moral standards in OCD. 相似文献
913.
Accurate timing is a critical aspect of motor control, yet the temporal structure of many mature behaviors emerges during learning from highly variable exploratory actions. How does a developing brain acquire the precise control of timing in behavioral sequences? To investigate the development of timing, we analyzed the songs of young juvenile zebra finches. These highly variable vocalizations, akin to human babbling, gradually develop into temporally stereotyped adult songs. We find that the durations of syllables and silences in juvenile singing are formed by a mixture of two distinct modes of timing: a random mode producing broadly distributed durations early in development, and a stereotyped mode underlying the gradual emergence of stereotyped durations. Using lesions, inactivations, and localized brain cooling, we investigated the roles of neural dynamics within two premotor cortical areas in the production of these temporal modes. We find that LMAN (lateral magnocellular nucleus of the nidopallium) is required specifically for the generation of the random mode of timing and that mild cooling of LMAN causes an increase in the durations produced by this mode. On the contrary, HVC (used as a proper name) is required specifically for producing the stereotyped mode of timing, and its cooling causes a slowing of all stereotyped components. These results show that two neural pathways contribute to the timing of juvenile songs and suggest an interesting organization in the forebrain, whereby different brain areas are specialized for the production of distinct forms of neural dynamics. 相似文献
914.
Steptoe A Hamer M Butcher L Lin J Brydon L Kivimäki M Marmot M Blackburn E Erusalimsky JD 《Brain, behavior, and immunity》2011,25(7):1292-1298
Low socioeconomic status (SES) may be associated with accelerated biological aging, but findings relating SES with telomere length have been inconsistent. We tested the hypotheses that shorter telomere length and telomerase activity would be related more robustly to education, an early life indicator of socioeconomic position, than to current indicators of socioeconomic circumstances. Healthy men and women aged 53–76 years from the Whitehall II epidemiological cohort provided blood samples from which telomere length was assessed in 448 and telomerase activity in 416. Educational attainment was classified into four levels, while household income and grade of employment were measured as indicators of current socioeconomic circumstances. Age, gender, blood pressure, glycated hemoglobin, high density lipoprotein cholesterol, smoking, body mass index and physical activity were included as covariates. We found that lower educational attainment was associated with shorter telomere length after controlling statistically for biological and behavioral covariates. Neither household income nor employment grade was related to telomere length. The association between telomere length and education remained significant after adjusting for current socioeconomic circumstances. In men, highest levels of telomerase activity were found in the lowest education group. We conclude that low SES defined in terms of education but not current socioeconomic circumstances is associated with shortened telomeres. Low educational attainment may be an indicator of long-term SES trajectories, and be associated with accumulated allostatic load resulting in telomere shortening. Education may also promote problem-solving skills leading to reduced biological stress responsivity, with favorable consequences for biological aging. 相似文献
915.
Palaniyappan L Mallikarjun P Joseph V White TP Liddle PF 《Schizophrenia Research》2011,129(2-3):163-168
In schizophrenia, morphological changes in the cerebral cortex have been primarily investigated using volumetric or cortical thickness measurements. In healthy subjects, as the brain size increases, the surface area expands disproportionately when compared to the scaling of cortical thickness. In this structural MRI study, we investigated the changes in brain surface area in schizophrenia by constructing relative areal contraction/expansion maps showing group differences in surface area using Freesurfer software in 57 patients and 41 controls. We observed relative areal contraction affecting Default Mode Network, Central Executive Network and Salience Network, in addition to other regions in schizophrenia. We confirmed the surface area reduction across these three large-scale brain networks by undertaking further region-of-interest analysis of surface area. We also observed a significant hemispheric asymmetry in the surface area changes, with the left hemisphere showing a greater reduction in the areal contraction maps. Our findings suggest that a fundamental disturbance in cortical expansion is likely in individuals who develop schizophrenia. 相似文献
916.
Palaniyappan L Mallikarjun P Joseph V Liddle PF 《Progress in neuro-psychopharmacology & biological psychiatry》2011,35(2):523-527
Poor insight is one of the most prominent clinical features of psychosis. Loss of insight in schizophrenia is characterised by abnormalities in awareness and attribution of the origin of pathological mental phenomena. Converging lines of investigations suggest that in healthy individuals, right posterior insula plays an important role in awareness and self-attribution of mental phenomena, contributing to the emergence of a sense of self (Craig, 2002; Farrer et al., 2003). In addition, neuroimaging studies investigating brain morphometry in schizophrenia have consistently reported deficits in the structure of insula (Glahn et al., 2008; Ellison-Wright and Bullmore, 2010). In the present study, we investigated the relationship between the morphometry of posterior insula and degree of insight in a sample of 57 patients in a stable phase of illness using high resolution Magnetic Resonance Imaging. We measured the cortical surface area and local white matter volume of posterior insula. A significant inverse relationship was found between right posterior insular structure and degree of insight in schizophrenia. No such relationship was noted for left posterior insula. Our results highlight the importance of a predominantly right-sided network that includes posterior insula as the neural basis of insight. Abnormalities in interoceptive awareness and self-appraisal of emotional states may contribute to the loss of insight seen in schizophrenia. 相似文献
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