B lymphocytes are critical antigen-presenting cells for the initiation of T cell-mediated autoimmune diabetes in nonobese diabetic mice

Nonobese diabetic (NOD) mice genetically deficient in B lymphocytes (NODJg mu(null)) are resistant to T cell-mediated autoimmune insulin-dependent diabetes mellitus (IDDM). Ig infusions from diabetic NOD donors did not abrogate IDDM resistance in NODJg mu(null) mice. However, T cell responses to the candidate pancreatic beta cell autoantigen glutamic acid decarboxylase (GAD), but not the control Ag keyhole limpet hemocyanin, were eliminated in NODJg mu(null) mice. To initially test whether they contribute to IDDM as APC, NOD B lymphocytes were transferred into NODJg mu(null) recipients. B lymphocytes transferred into unmanipulated NODJg mu(null) recipients were rejected by MHC class I-restricted T cells. Stable T and B lymphocyte repopulation was achieved in irradiated NODJg mu(null) mice reconstituted with syngeneic bone marrow admixed with NOD B lymphocytes. IDDM susceptibility was restored in NODJg mu(null) mice reconstituted with syngeneic marrow plus B lymphocytes, but not with syngeneic marrow only. T cell responses to GAD were restored only in NODJg mu(null) mice reconstituted with syngeneic marrow plus B lymphocytes. Hence, B lymphocytes appear to contribute to IDDM in NOD mice as APC with a preferential ability to present certain beta cell Ags such as GAD to autoreactive T cells.     

Use of evidence in the process of practice change in a clinical team: a study-forming part of the Autocontrol Project

The Autocontrol Project is concerned with the accessing, processing and communication of high quality information so that a clinical team can make and implement decisions for practice change, and then evaluate if improvement has been achieved. High quality information is used as evidence for change. In this study, we have evaluated how evidence is used by a clinical team to explain an identified problem of inappropriate use of blood gas tests. In an experimental study of the Surgical Intensive Care Unit, video recordings of team meetings of nurses and doctors were undertaken, structured according to a problem-based format. Evidence of current practice patterns derived from the hospital information system, as well as the results of a questionnaire to the unit's staff about knowledge and use of blood gas measurements, were supplied to the participants beforehand. At the second meeting, the output of the first meetings and a summarised analysis of pertinent literature were made available. This second meeting was required to finalise the list of causes of inappropriate blood gas use and propose pragmatic strategies for practice change. The video data of the meetings were coded to analyse the use of evidence, the categories of causes, issues and solutions proposed, and the quality of team interaction. The results indicate that in order to achieve consensus, the team used different types of evidence, including objective evidence of practice patterns, personal experience about direct and indirect organisational influences, and literature-based research evidence of best practice. Furthermore, group dynamics were favoured by the problem-based meeting structure, and a high level of cognitive critiquing between team members was observed. This research suggests that a combination of approaches involving identification of both operational factors (e.g. appropriate access to different types of evidence and meeting structure) and cognitive and behavioural approaches (e.g. ensuring expression of different viewpoints) is needed to support strategic decision-making for practice change in a clinical unit. This combined approach should favourably influence the provision of an effective and efficient evidence support environment for the clinical team.     

Ca2+ currents in compensated hypertrophy and heart failure

Transmembrane voltage-gated Ca2+ channels play a central role in the development and control of heart contractility which is modulated by the concentration of free cytosolic calcium ions (Ca2+). Ca2+ channels are closed at the normal membrane resting potential of cardiac cells. During the fast upstroke of the action potential (AP), they are gated into an open state by membrane depolarisation and thereby transduce the electrical signal into a chemical signal. In addition to its contribution to the AP plateau, Ca2+ influx through L-type Ca2+ channels induces a release of Ca2+ ions from the sarcoplasmic reticulum (SR) which initiates contraction. Because of their central role in excitation-contraction (E-C) coupling, L-type Ca2+ channels are a key target to regulate inotropy [1]. The role of T-type Ca2+ channels is more obscure. In addition to a putative part in the rhythmic activity of the heart, they may be implicated at early stages of development and during pathology of contractile tissues [2]. Despite therapeutic advances improving exercise tolerance and survival, congestive heart failure (HF) remains a major problem in cardiovascular medicine. It is a highly lethal disease; half of the mortality being related to ventricular failure whereas sudden death of the other patients is unexpected [3]. Although HF has diverse aetiologies, common abnormalities include hypertrophy, contractile dysfunction and alteration of electrophysiological properties contributing to low cardiac output and sudden death. A significant prolongation of the AP duration with delayed repolarisation has been observed both during compensated hypertrophy (CH) and in end-stage HF caused by dilated cardiomyopathy (Fig. 1A) [4-8]. This lengthening can result from either an increase in inward currents or a decrease in outward currents or both. A reduction of K+ currents has been demonstrated [6,9]. Prolonged Na+/Ca2+ exchange current may also be involved [9]. In contrast, there is a large variability in the results concerning Ca2+ currents (ICa). The purpose of this paper is to review results obtained in various animal models of CH and HF with special emphasis on recent studies in human cells. We focus on: (i) the pathophysiological role of T-type Ca2+ channels, present in some animal models of hypertrophy; (ii) the density and properties of L-type Ca2+ channels and alteration of major physiological regulations of these channels by heart rate and beta-adrenergic receptor stimulation; and (iii) recent advances in the molecular biology of the L-type Ca2+ channel and future directions.     

Range restriction and the Graduate Record Examination.

Comments on the article by R. J. Sternberg and W. M. Williams (see record 1997-04591-002) regarding the empirical validity of the Graduate Record Examination (GRE) in predicting graduate student performance in psychology. Sternberg and Williams claim that their results suggest the need for new measures for use in graduate admissions, and many will surely interpret their results to suggest that GRE scores have little valid use. Actually, however, their results are fully consistent with the opposing view that it will never be possible to improve much on the current admissions policies at Yale University and its direct competitors. Such improvements might be possible, but these results do nothing to bolster that conjecture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Have code: Will travel.

Discusses the Code of Ethics of the Psychological Society of Ireland (1991) and possible changes to it. The author states that the Board of Professional Conduct is examining the Canadian Code of Ethics for Psychologists. Although the author is not certain how closely the Psychological Society of Ireland will follow the Canadian Code of Ethics for Psychologists, the Canadian code of Ethics is considered a landmark that shapes understanding of ethical issues in Ireland. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Community psychology in the Canadian psychological family.

Reviews the status of community psychology in the history of psychology in Canada, emphasizing the early precedents of applied mental health and community interventions. Findings are presented from inquiries into undergraduate and graduate training in community psychology in Canada. After assessing current problems in the subdiscipline, the author makes recommendations for future directions and discusses the potential usefulness of community psychology to professional psychology in meeting the challenges of public mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is there a role for continuation phase cognitive therapy for depressed outpatients?

Two pilot studies evaluated the rate of relapse or recurrence (i.e., major depressive disorder) after cognitive therapy (CT). Two sequential cohorts included outpatients who responded to acute phase CT (A-CT) and who agreed to monthly, treatment-free follow-up. In Study 1, the Kaplan-Meier technique estimated relapse and recurrence rates of 40% at 6 months, 45% at 8 months, 50% at 12 months, 67% at 18 months, and 74% at 24 months. In Study 2, responders to A-CT received 8 months (10 sessions) of continuation phase CT (C-CT). In Study 2, relapse or recurrence was 20% at 6 and 8 months, 27% at 12 months, and 36% at 18 and 24 months after A-CT. An exploratory log-rank test showed that relapse or recurrence-free survival was greater in Study 2 than in Study 1. If replicated, this result suggests that C-CT can reduce depressive relapse or recurrence. Alternative explanations are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When is less treatment better? The role of social anxiety in matching methadone patients to psychosocial treatments.

In response to a need to match drug users to the most appropriate and cost-effective level of care, it was hypothesized that socially anxious methadone-maintained patients would attain greater benefit from coping skills training provided in the context of a low-intensity enhanced standard methadone maintenance intervention (E-STD) than in the context of a high-intensity, socially demanding day treatment program (DTP). Social anxiety was assessed in 307 methadone-maintained patients using the Social Anxiety and Distress Scale prior to randomization to either E-STD or DTP. The hypothesis was supported: Socially anxious patients were drug free longer during treatment, were more likely to be abstinent at treatment completion, and had greater reductions in HIV risk behaviors if assigned to the lower intensity intervention, which was provided at ? the cost of the DTP. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a conceptual model of organizational regression.

This article presents an elaborated model of organizational regression suggesting that, within the framework of general systems and catastrophe theory, organizational units and whole enterprises can be viewed as struggling to attain a state of super-resilience that enables them to cope effectively with a large number of regressive forces. The model comprises 6 phases of organizational regression that occur either in a 10-stage process or in a chaotically unpredictable but behaviorally understandable and orderly sequence. Internal and external regressive forces that constantly pressure an organization toward less effective performance and more primitive behavior are identified. Organizational barriers and balancing forces that counter the regressive pressures are also described, along with the consequences of regression for individuals and enterprises. Several brief case illustrations (e.g., Montgomery Ward, Apple Computer, and General Electric Corporation) are provided to highlight aspects of this conceptual approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved)