In vivo antibacterial efficacy of ultrasound after hand and rotary instrumentation in human mandibular molars

The purpose of this prospective, randomized, single-blind study was to compare the in vivo antibacterial efficacy of a hand/rotary technique versus a hand/rotary/ultrasound technique in mesial root canals of necrotic mandibular molars. The hand/rotary group consisted of 16 mesial roots prepared with a hand/rotary technique. The hand/rotary/ultrasound group consisted of 15 mesial roots prepared similarly, followed by 1 minute of ultrasonic irrigation per canal with an ultrasonic needle in a MiniEndo unit and 15 mL/canal of 6.0% sodium hypochlorite. Canals were sampled before and after instrumentation and after 1 minute of ultrasonic irrigation. Samples were incubated anaerobically on reduced blood agar for 7 days at 37 degrees C, and colony-forming units (CFUs) were counted. The addition of 1 minute of ultrasonic irrigation resulted in significant (p = .0006) reduction in CFU count and positive cultures (p = .0047). Logistic regression analysis indicated the addition of ultrasonic irrigation was 7 times more likely to yield a negative culture.     

Reward sensitivity to faces versus objects in children: an ERP study

How children respond to social and nonsocial rewards has important implications for understanding social cognitive development. Adults find faces intrinsically rewarding. However, little is known about how children respond to face vs nonface rewards. We utilized event-related potentials (the stimulus-preceding negativity, SPN) to measure differences in reward anticipation during a guessing game in 6- to 8-year-olds. Children were presented with reward indicators accompanied by incidental face or nonface stimuli. Nonface stimuli were comprised of scrambled faces in the shape of arrows, controlling for low-level properties of the two conditions. Children showed an increased SPN when the reward stimuli were accompanied by faces, relative to nonface stimuli. This suggests that children find a face stimulus more rewarding than a nonface stimulus. The results have important implications for processing social vs nonsocial rewards in typically developing children, and allow testing of populations with deficits in social reward processing, such as autism spectrum disorder.     

Effects of optimism on psychological and physical well-being: Theoretical overview and empirical update

The primary purpose of this paper is to review recent research examining the beneficial effects of optimism on psychological and physical well-being. The review focuses on research that is longitudinal or prospective in design. Potential mechanisms are also identified whereby the beneficial effects of optimism are produced, focusing in particular on how optimism may lead a person to cope more adaptively with stress. The paper closes with a brief consideration of the similarities and differences between our own theoretical approach and several related approaches that have been taken by others.Preparation of this article was facilitated by NSF grants BNS-9010425 and BNS 90-11653, by NIH grant 1R01HL4432-01A1, and by American Cancer Society grant PBR-61173. Michael Scheier would like to dedicate this article to the fighting spirit and optimism of his mother, Mary Scheier, who was lying critically injured in the hospital during the time in which it was being written.     

Using evidence to enhance the recovery of patients undergoing colorectal surgery: part 2

This is the second part of a three-part series describing how an enhanced recovery clinical pathway uses a multidisciplinary team to reduce postoperative stress and complications, improve recovery, and decrease hospital length of stay without affecting patient safety for patients undergoing colorectal surgery. Last month, patient education and discharge planning were discussed. This part discusses multimodal analgesia and standardized postoperative nausea and vomiting prophylaxis. Next month, fluids, diet, tubes and drains, and early mobilization will be discussed.     

Optimism,pessimism, and postpartum depression

This study examined the role of dispositional optimism versus pessimism as a moderator of the tendency to become depressed after a specific stressful life change: the birth of a child. The optimism-pessimism dimension was operationally defined as generalized expectancies for favorable versus unfavorable life outcomes. Both optimism and depressive mood were assessed several weeks before childbirth. Depressive mood was measured again three weeks postpartum. Even after statistically controlling for initial dysphoria, optimism was inversely correlated with subsequent dysphoria. The effect of optimism was most pronounced among women who initially were not depressed, suggesting that optimism confers resistance to the development of depressive symptoms. Discussion centers on the relation between optimism and attributional style, and on the self-regulatory functions of optimism.     

Inhibin A is an endocrine stimulator of bone mass and strength

Gonadal function plays a major role in bone homeostasis. It is widely held that the skeletal consequences of hypogonadism are solely due to a loss of sex steroids; however, increases in bone turnover begin during perimenopause before decreases in serum estradiol levels. These data and our demonstration that inhibins acutely regulate bone cell differentiation in vitro led us to test whether inhibin A (InhA) regulates bone mass in vivo. Using a transgenic model of inducible human InhA expression, InhA increased total body bone mineral density, increased bone volume, and improved biomechanical properties at the proximal tibia in intact mice and also prevented the loss of BMD and bone volume and strength associated with gonadectomy at both the spine and proximal tibia. In addition, InhA increased mineral apposition rate, double-labeled surface, and serum osteocalcin levels in vivo and osteoblastogenesis ex vivo without affecting osteoclast number or activity. Together these results demonstrate novel stimulatory effects of InhA on the skeleton in vivo. These studies provide in vivo evidence demonstrating that gonadal factors other than sex steroids play an important role in regulating bone mass and strength and, combined with our previous clinical data, suggest that gonadal InhA may be a component of the normal endocrine repertoire that regulates bone quality in both the axial and appendicular skeleton.