Using a five-factor lens to explore the relation between personality traits and violence in psychiatric patients

Recent work suggests that predictors of violence are similar for individuals with and without mental illness. Although psychopathy is among the most potent of such predictors, the nature of its relation to violence is unclear. On the basis of a sample of 769 civil psychiatric patients, the authors explore the possibility that measures of psychopathy provide a glimpse of higher order personality traits that predispose individuals toward violence. Results indicate that general traits captured by a measure of the 5-factor model, particularly antagonism, were relatively strongly associated with violence and shared most of their violence-relevant variance with a leading measure of psychopathy. Because interpersonal and affective features of psychopathy are less important than basic traits of antagonism in postdicting violence, it may be appropriate to broaden focus in risk assessment to patients' basic personality traits.     

Passive movements of the head do not abolish anticipatory firing properties of head direction cells

Neurons in the anterior dorsal thalamic nucleus (ADN) of the rat selectively discharge in relation to the animal's head direction (HD) in the horizontal plane. Temporal analyses of cell firing properties reveal that their discharge is optimally correlated with the animal's future directional heading by approximately 24 ms. Among the hypotheses proposed to explain this property is that ADN HD cells are informed of future head movement via motor efference copy signals. One prediction of this hypothesis is that when the rat's head is moved passively, the anticipatory time interval (ATI) will be attenuated because the motor efference signal reflects only the active contribution to the movement. The present study tested this hypothesis by loosely restraining the animal and passively rotating it through the cell's preferred direction. Contrary to our prediction, we found that ATI values did not decrease during passive movement but in fact increased significantly. HD cells in the postsubiculum did not show the same effect, suggesting independence between the two sites with respect to anticipatory firing. We conclude that it is unlikely that a motor efference copy signal alone is responsible for generating anticipatory firing in ADN HD cells.     

An evaluation of home volume ventilators that support open-circuit mouthpiece ventilation

BACKGROUND: Open-circuit mouthpiece ventilation (MPV) is a form of noninvasive ventilation that can be used to provide portable daytime ventilatory support for neuromuscular patients with chronic respiratory failure. MPV has been reported to reduce the risk of respiratory infection due to tracheostomy, and to improve cough and voice function and patient quality of life. Despite these potential benefits, mouthpiece ventilation is not widely used. This may be due in part to the fact that little information is available as to which ventilators can support this application. OBJECTIVE: To determine which volume-cycled portable home ventilators currently available in the United States will support MPV, and what peak inspiratory flow rates create adequate circuit pressure to prevent low-pressure alarming. METHODS: We used a commercially available MPV breathing circuit with a set tidal volume range of 500\N1,000 mL with each of 8 ventilators currently available in the United States. RESULTS: Six of the 8 ventilators supported MPV: Respironics Lifecare PLV-100 and PLV Continuum, Mallinckrodt Achieva PSO2, Pulmonetics LTV800, Newport HT50, and Uni-Vent Eagle 754.     

NO/redox disequilibrium in the failing heart and cardiovascular system

There is growing evidence that the altered production and/or spatiotemporal distribution of reactive oxygen and nitrogen species creates oxidative and/or nitrosative stresses in the failing heart and vascular tree, which contribute to the abnormal cardiac and vascular phenotypes that characterize the failing cardiovascular system. These derangements at the integrated system level can be interpreted at the cellular and molecular levels in terms of adverse effects on signaling elements in the heart, vasculature, and blood that subserve cardiac and vascular homeostasis.     

Esophageal and gastric pressure measurements

The measurement of esophageal and gastric pressures with balloon-tipped catheters has been used with great success over the past half century to delineate the physiology of the mechanical respiratory system. Pleural pressure and abdominal pressure values estimated from esophageal and gastric pressure measurements allow analysis of lung and chest wall compliance, as well as work of breathing, respiratory muscle function, and the presence of diaphragm paralysis. Although much of the use of these measurement techniques has been in the clinical laboratory, to improve the understanding of basic physiologic mechanisms, the techniques have also been used in clinical situations to diagnose diaphragm paralysis, assess the work of breathing during mechanical ventilation, and estimate pulmonary compliance. In this article I review the historical background, physiology, placement techniques, and potential clinical applications of esophageal and gastric pressure measurements. In addition, I will briefly review the measurement of bladder pressure, which is a related topic.     

Asthma epidemiology: has the crisis passed?

PURPOSE OF REVIEW: Asthma is a difficult, resource-intensive disease that can result in symptoms, hospitalization and, in rare cases, death. In the past few decades, there has been an abundance of evidence showing the prevalence of asthma to be increasing in certain regions. However, reports have recently emerged suggesting that asthma prevalence has stabilized. This has led to debate among researchers whether increases in asthma prevalence have come to an end. We reviewed recent literature in search of answers to the ongoing debate on whether the asthma crisis is over. RECENT FINDINGS: In contrast with past reports, several recent studies have reported a stabilization of asthma prevalence. However, based on repeated cross-sectional studies, findings regarding the stabilization of asthma prevalence have been inconsistent, especially when considering the heterogeneity of the disease, which can result in a variety of patterns concerning asthma diagnosis, symptoms, and allergic sensitization. Temporal trends considering physician visits, hospitalizations, and mortality have been more consistent, with stabilizing and decreasing patterns of asthma burden in recent years. SUMMARY: Because reasons for the original increases in asthma prevalence remain unclear, an explanation for the apparent stabilization of asthma prevalence reported in some studies also remains elusive. This is compounded by the difficulty in defining asthma accurately in population studies and inconsistencies in the results of prevalence estimation among repeated cross-sectional studies. Efforts should be made to continue monitoring asthma prevalence and to begin monitoring asthma prevalence in regions where environmental and social changes are occurring.