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61.
James P Kesby Robert K Heaton Jared W Young Anya Umlauf Steven P Woods Scott L Letendre Athina Markou Igor Grant Svetlana Semenova 《Neuropsychopharmacology》2015,40(8):1899-1909
Methamphetamine dependence is a common comorbid condition among people living with HIV, and may exacerbate HIV-associated neurocognitive disorders. Animal models of neuroAIDS suggest that the gp120 protein may also cause cognitive impairment. The present work evaluated the separate and combined effects of HIV/gp120 and methamphetamine on learning and executive functions in both humans and transgenic mice. Human participants were grouped by HIV serostatus (HIV+ or HIV−) and lifetime methamphetamine dependence (METH+ or METH−). A neurocognitive test battery included domain-specific assessments of learning and executive functions. Mice (gp120+ and gp120−) were exposed to either a methamphetamine binge (METH+) or saline (METH−), then tested in the attentional-set-shifting task to assess learning and executive functions. In humans, HIV status was associated with significant impairments in learning, but less so for executive functions. The frequency of learning impairments varied between groups, with the greatest impairment observed in the HIV+/METH+ group. In mice, gp120 expression was associated with impairments in learning but not reversal learning (executive component). The greatest proportion of mice that failed to complete the task was observed in the gp120+/METH+ group, suggesting greater learning impairments. Our cross-species study demonstrated that HIV in humans and gp120 in mice impaired learning, and that a history of methamphetamine exposure increased the susceptibility to HIV-associated neurocognitive deficits in both species. Finally, the similar pattern of results in both species suggest that the gp120 protein may contribute to HIV-associated learning deficits in humans. 相似文献
62.
Valerie Voon Laurel S Morris Michael A Irvine Christian Ruck Yulia Worbe Katherine Derbyshire Vladan Rankov Liana RN Schreiber Brian L Odlaug Neil A Harrison Jonathan Wood Trevor W Robbins Edward T Bullmore Jon E Grant 《Neuropsychopharmacology》2015,40(4):804-812
Pathological behaviors toward drugs and food rewards have underlying commonalities. Risk-taking has a fourfold pattern varying as a function of probability and valence leading to the nonlinearity of probability weighting with overweighting of small probabilities and underweighting of large probabilities. Here we assess these influences on risk-taking in patients with pathological behaviors toward drug and food rewards and examine structural neural correlates of nonlinearity of probability weighting in healthy volunteers. In the anticipation of rewards, subjects with binge eating disorder show greater risk-taking, similar to substance-use disorders. Methamphetamine-dependent subjects had greater nonlinearity of probability weighting along with impaired subjective discrimination of probability and reward magnitude. Ex-smokers also had lower risk-taking to rewards compared with non-smokers. In the anticipation of losses, obesity without binge eating had a similar pattern to other substance-use disorders. Obese subjects with binge eating also have impaired discrimination of subjective value similar to that of the methamphetamine-dependent subjects. Nonlinearity of probability weighting was associated with lower gray matter volume in dorsolateral and ventromedial prefrontal cortex and orbitofrontal cortex in healthy volunteers. Our findings support a distinct subtype of binge eating disorder in obesity with similarities in risk-taking in the reward domain to substance use disorders. The results dovetail with the current approach of defining mechanistically based dimensional approaches rather than categorical approaches to psychiatric disorders. The relationship to risk probability and valence may underlie the propensity toward pathological behaviors toward different types of rewards. 相似文献
63.
64.
Dustin T. Rae Jonah D. Hocum Victor Bii H. Joachim Deeg Grant D. Trobridge 《Oncotarget》2015,6(31):30664-30674
Using a novel retroviral shuttle vector approach we identified genes that collaborate with a patient derived RUNX1 (AML1) mutant. RUNX1 mutations occurs in 40% of myelodysplastic syndromes (MDS). MDS are a group of hematopoietic stem cell disorders that are characterized by dysplasia that often progress to acute myeloid leukemia (AML). Our goal was to identify genes dysregulated by vector-mediated genotoxicity that may collaborate with the RUNX1 mutant (D171N). D171N expressing cells have a survival and engraftment disadvantage and require additional genetic lesions to survive and persist. By dysregulating genes near the integrated vector provirus, the shuttle vector can promote transformation of D171N cells and tag the nearby genes that collaborate with D171N. In our approach, a gammaretroviral shuttle vector that expresses D171N is used to transduce CD105+, Sca-1+ mouse bone marrow. Mutagenized cells are expanded in liquid culture and vector integration sites from surviving cells are then identified using a retroviral shuttle vector approach. We repeatedly recovered integrated vector proviruses near genes (Itpkb, Ccdc12, and Nbeal2). To assess the prognostic significance of the genes identified we examined differential expression, overall survival, and relapse free survival of AML patients with alteration in the genes identified using The Cancer Genome Atlas (TCGA) AML data set. We found that ITPKB functions as an independent factor for poor prognoses and RUNX1 mutations in conjunction with ITPKB, CCDC12, and NBEAL2 have prognostic potential in AML. 相似文献
65.
Aim. This paper reports a systematic review to identify the education needs of the workforce within primary care to promote the effective delivery of integrated health and social care services. Background. The need for different professionals to work more closely dominates global health policy. The drive to develop a workforce prepared for the future is crucial to the success of integrated services. However, some have argued that nurses are ill‐equipped to meet the challenges of integrated service provision. The ability to work interprofessionally is an important skill which needs to be developed to support integrated working. Methods. Structured searches were undertaken on organizational websites and the Caredata, CINAHL, Cochrane Library, MEDLINE, Sociofile databases between December 2002 and April 2004 to identify policy documents and primary research studies. The robustness of identified research studies were appraised using recognized appraisal tools. Findings. Six themes were identified which indicate essential elements needed for integrated care. The need for effective communication between professional groups within teams and an emphasis on role awareness are central to the success of integrated services. In addition, education about the importance of partnership working and the need for professionals to develop skills in relation to practice development and leadership through professional and personal development is needed to support integrated working. Conclusion. Education which embeds essential attributes to integrated working is needed to advance nursing practice for interprofessional working. Further research exploring this and its impact on integrated provision is essential to ensure that evidence‐based services are provided. The reinforcement of partnerships between higher education institutions and health and social care organizations should ensure that the workforce is educated to manage continuous change in service delivery. Innovative ways of teaching and learning which promote inter‐professional working need to be explored. 相似文献
66.
K K Hampton P J Grant J Primrose H G Dean J A Davies C R Prentice 《Clinical science (London, England : 1979)》1991,81(2):257-260
1. During major abdominal surgery there are increases in Factor VIII and plasminogen activator activity, associated with elevated plasma concentrations of vasopressin, of a magnitude shown to affect haemostasis. 2. To investigate the mechanisms involved in the haemostatic response to surgery, 12 patients undergoing fibre-optic colonoscopy were studied, of which six had a complete and six had an incomplete examination. 3. Venous blood samples were taken before, during and after the procedure for assay of plasma vasopressin, adrenaline and noradrenaline concentrations, Factor VIII coagulant activity, von Willebrand factor antigen level, euglobulin clot lysis time, tissue-type plasminogen activator activity and tissue-type plasminogen activator inhibition. 4. In the six patients who underwent a complete procedure the median plasma vasopressin concentration rose from 0.6 pg/ml to 153 pg/ml during colonoscopy. Factor VII coagulant activity rose from 0.9 to 2.4 i.u./ml and von Willebrand factor antigen level rose from 139 to 224%. Plasminogen activator activity increased from 20 to 144 units and tissue-type plasminogen activator activity rose from 107 to 1338 m-i.u./ml, whereas tissue-type plasminogen activator inhibition fell from 4.8 to 1.0 i.u./ml. 5. In the six patients in whom a limited procedure was performed, there were no changes in haemostatic function or in plasma vasopressin concentration. Plasma concentrations of adrenaline and noradrenaline did not change in either group. 6. The results indicate that vasopressin regulates the intrinsic coagulation pathway and fibrinolytic system in the absence of adrenaline release. 相似文献
67.
68.
Training communication partners of people with traumatic brain injury: A randomised controlled trial
Background: Communication disorders after traumatic brain injury (TBI) are difficult to modify due to the cognitive limitation imposed by frontal lobe damage. As an alternative approach, this paper describes a training programme designed to improve communication partners' responsiveness to people with TBI during routine service inquiries with a community agency. Aims: To evaluate the effectiveness of a training programme aimed at improving the communication of police officers during service encounters with people with TBI. Methods & Procedures: A total of 20 police officers were randomly assigned to two groups (training or control). Prior to the 6‐week training programme, participants with TBI made a routine telephone inquiry to the police officers. Training focused on specific aspects of telephone inquiries previously documented to be aberrant in service encounters of people with TBI. Following the training programme, police subjects received another telephone service inquiry. Service encounters were transcribed and analysed using generic structure potential analysis. Outcome & Results: Comparison of pre‐ and post‐training measures indicated that trained police had learned strategies to successfully establish the nature of the inquiry, provide a clear answer to the inquiry, and ensure appropriate leave taking, resulting in more efficient, focused interactions in the post‐training telephone calls. People with TBI also altered their communication in the post‐training calls, with reduced episodes of unrelated utterances and an increased proportion of the interaction devoted to completing the service encounter. This appeared to be in response to the communicative options they were given. Conclusions: This study demonstrates the efficacy of an approach based on training communication partners rather than people with TBI themselves. Training communication partners led to the provision of appropriate feedback, support, and structure of everyday interactions. Service encounters account for a significant amount of everyday communication exchanges, therefore training service providers has the potential to have a significant impact on the communicative effectiveness of people with TBI. 相似文献
69.
70.
Hepatic endothelial CCL25 mediates the recruitment of CCR9+ gut-homing lymphocytes to the liver in primary sclerosing cholangitis 总被引:5,自引:0,他引:5
Eksteen B Grant AJ Miles A Curbishley SM Lalor PF Hübscher SG Briskin M Salmon M Adams DH 《The Journal of experimental medicine》2004,200(11):1511-1517
Primary sclerosing cholangitis (PSC), a chronic inflammatory liver disease characterized by progressive bile duct destruction, develops as an extra-intestinal complication of inflammatory bowel disease (IBD) (Chapman, R.W. 1991. Gut. 32:1433-1435). However, the liver and bowel inflammation are rarely concomitant, and PSC can develop in patients whose colons have been removed previously. We hypothesized that PSC is mediated by long-lived memory T cells originally activated in the gut, but able to mediate extra-intestinal inflammation in the absence of active IBD (Grant, A.J., P.F. Lalor, M. Salmi, S. Jalkanen, and D.H. Adams. 2002. Lancet. 359:150-157). In support of this, we show that liver-infiltrating lymphocytes in PSC include mucosal T cells recruited to the liver by aberrant expression of the gut-specific chemokine CCL25 that activates alpha4beta7 binding to mucosal addressin cell adhesion molecule 1 on the hepatic endothelium. This is the first demonstration in humans that T cells activated in the gut can be recruited to an extra-intestinal site of disease and provides a paradigm to explain the pathogenesis of extra-intestinal complications of IBD. 相似文献