Is there a definition of remission in late-life depression that predicts later relapse?

Remission of depressive symptoms is the goal of all antidepressant therapy. Rating scales define remission in clinical trials, but it is unclear how well these definitions predict risk of later relapse. We measured the sensitivity and specificity of a range of Montgomery-Asberg Depression Rating Scale (MADRS) cutoff scores at 3- and 6-months, wherein scores above a given cutoff would predict relapse over an 18-month period. We examined 153 elderly depressed subjects exhibiting a MADRS < or = 15 after 3 or 6 months of antidepressant therapy. Subjects who subsequently exhibited a MADRS > 15 during the 18-month study period were defined as relapsed. Receiver operating characteristic (ROC) curves were developed and area under the curve (AUC) values calculated for the sensitivity and specificity of 3- and 6-month MADRS scores to predict future relapse. The 3-month ROC had an AUC value of 0.63; the 6-month ROC had an AUC value of 0.66. There was no MADRS cutoff found that could predict likelihood of relapse with good sensitivity and specificity. A post hoc analysis where relapse rate was adjusted by controlling for medical comorbidity, disability, and social support showed no change in the ROCs or AUC values. The higher the MADRS score at 3 and 6 months, the greater the likelihood of relapse. With no clean MADRS cutoff score, the goal of antidepressant therapy should be the lowest possible degree of depressive symptomatology to minimize risk of later relapse. Definitions of remission that are better associated with longer-term outcomes are needed.     

Current status of DNA vaccines in veterinary medicine

DNA vaccination entails administration of the DNA itself encoding antigen to direct synthesis of the antigen directly in the target organism. The target organism's immune system recognizes the antigen, and generates humoral (antibody)- and/or cell-mediated immune response. DNA vaccines afford numerous advantages over conventional vaccines, including ease of production, stability and transport. They overcome the need to cultivate dangerous infectious agents, and provide a possibility to vaccinate against multiple pathogens in a single shot. DNA vaccination is beginning to be explored for many pathogens of veterinary interest. The status of DNA vaccines in poultry, livestock and companion animals is reviewed here. While examples of DNA vaccines being tested in the veterinary field are not numerous, the early studies highlight the potential DNA vaccinology offers in veterinary medicine.     

Effect of one-rescuer compression/ventilation ratios on cardiopulmonary resuscitation in infant, pediatric, and adult manikins.

OBJECTIVE: Optimal chest compression to ventilation ratio (C:V) for one-rescuer cardiopulmonary resuscitation (CPR) is not known, with current American Heart Association recommendations 3:1 for newborns, 5:1 for children, and 15:2 for adults. C:V ratios influence effectiveness of CPR, but memorizing different ratios is educationally cumbersome. We hypothesized that a 10:2 ratio might provide adequate universal application for all age arrest victims. DESIGN: Clinical study. SETTING: Tertiary care children's hospital. SUBJECTS: Thirty-five health care providers. INTERVENTIONS: Thirty-five health care providers performed 5-min epochs of one-rescuer CPR at C:V ratios of 3:1, 5:1, 10:2, and 15:2 in random order on infant, pediatric, and adult manikins. Compressions were paced at 100/min by metronome. The number of effective compressions and ventilations delivered per minute was recorded by a trained basic life support instructor. Subjective assessments of fatigue (self-report) and exertion (change in rescuer pulse rate compared with baseline) were assessed. Analysis was by repeated measures analysis of variance and paired Student's t-test. MEASUREMENTS AND MAIN RESULTS: Effective infant compressions per minute did not differ by C:V ratio, but ventilations per minute were greater at 3:1 vs. 5:1, 10:2, and 15:2 (p < .05). Effective pediatric compressions per minute were less at 3:1 vs. 5:1, 10:2, and 15:2 (p < .05) and not different between 5:1, 10:2, and 15:2 ratios. Effective pediatric ventilations per minute were greater at 3:1 than all other ratios and both 5:1 and 10:2 were >15:2 (p < .05). Effective adult compressions per minute were progressively greater with 3:1 vs. 5:1 vs. 10:2 vs. 15:2 (p < .05). Self-efficacy was assessed, and rescuers always subjectively rated 10:2 and 15:2 ratios as easier than 5:1 or 3:1 ratios for all manikins. Rescuer pulse change (exertion) was greater after pediatric and adult vs. infant CPR (p < .05), with no significant difference by C:V ratio. CONCLUSIONS: C:V ratio and manikin size have a significant influence on the number of effective compressions and ventilations delivered during ideal, metronome-paced, one-rescuer CPR. Low ratios of 3:1, 5:1, and 10:2 favor ventilation, and high ratios of 15:2 favor compression, especially in adult manikins. Rescuers subjectively preferred C:V ratios of 10:2 and 15:2 over 3:1 or 5:1. Infant CPR caused less exertion and subjective fatigue than pediatric or adult CPR technique, without significant difference by C:V ratio. We speculate that a universal 10:2 C:V ratio for one-rescuer layperson CPR is physiologically reasonable but warrants further study with particular attention to educational value and technique retention.     

Age and sex effects on brain morphology

1. 1. Brain morphology can be assessed readily in vivo using magnetic resonance imaging (MRI).

2. 2. In this study, the effects of age and sex on whole-brain morphology were examined using an operator-controlled computer-segmentation protocol.

3. 3. Results indicated that age was associated with gray-matter volume reduction.

4. 4. Brain-size differences between males and females were primarily attributable to whitematter volume.

5. 5. This study confirms the importance of controlling for age and sex in brain-morphology studies.