Longitudinal Assessment of Food Intake, Fecal Energy Loss, and Energy Expenditure After Roux-en-Y Gastric Bypass Surgery in High-Fat-Fed Obese Rats

Background

The efficacy of Roux-en-Y gastric bypass (RYGB) surgery to produce weight loss has been well-documented, but few studies have measured the key components of energy balance, food intake, and energy expenditure longitudinally.

Methods

Male Sprague-Dawley rats on a high-fat diet underwent either RYGB, sham operation, or pair feeding and were compared to chow-fed lean controls. Body weight and composition, food intake and preference, energy expenditure, fecal output, and gastric emptying were monitored before and up to 4 months after intervention.

Results

Despite the recovery of initially decreased food intake to levels slightly higher than before surgery and comparable to sham-operated rats after about 1 month, RYGB rats maintained a lower level of body weight and fat mass for 4 months that was not different from chow-fed age-matched controls. Energy expenditure corrected for lean body mass at 1 and 4 months after RYGB was not different from presurgical levels and from all other groups. Fecal energy loss was significantly increased at 6 and 16 weeks after RYGB compared to sham operation, and there was a progressive decrease in fat preference after RYGB.

Conclusions

In this rat model of RYGB, sustained weight loss is achieved by a combination of initial hypophagia and sustained increases in fecal energy loss, without change in energy expenditure per lean mass. A shift away from high-fat towards low-fat/high-carbohydrate food preference occurring in parallel suggests long-term adaptive mechanisms related to fat absorption.     

Development of simultaneous pitch encoding: infants show a high voice superiority effect

Infants must learn to make sense of real-world auditory environments containing simultaneous and overlapping sounds. In adults, event-related potential studies have demonstrated the existence of separate preattentive memory traces for concurrent note sequences and revealed perceptual dominance for encoding of the voice with higher fundamental frequency of 2 simultaneous tones or melodies. Here, we presented 2 simultaneous streams of notes (15 semitones apart) to 7-month-old infants. On 50% of trials, either the higher or the lower note was modified by one semitone, up or down, leaving 50% standard trials. Infants showed mismatch negativity (MMN) to changes in both voices, indicating separate memory traces for each voice. Furthermore, MMN was earlier and larger for the higher voice as in adults. When in the context of a second voice, representation of the lower voice was decreased and that of the higher voice increased compared with when each voice was presented alone. Additionally, correlations between MMN amplitude and amount of weekly music listening suggest that experience affects the development of auditory memory. In sum, the ability to process simultaneous pitches and the dominance of the highest voice emerge early during infancy and are likely important for the perceptual organization of sound in realistic environments.     

Posttraumatic stress disorder and odds of major invasive procedures among U.S. Veterans Affairs patients

Objectives

Although individuals with posttraumatic stress disorder (PTSD) are at heightened risk for several serious health conditions, research has not examined how having PTSD impacts receipt of invasive procedures that may alleviate these problems. We examined whether PTSD, after controlling for major depression, was associated with odds of receiving common types of major invasive procedures, and whether race, ethnicity, and gender was associated with odds of procedures.

Methods

Veterans Health Administration patients with PTSD and/or depression were age-matched with patients without these disorders. The odds of invasive hip/knee, digestive system, coronary artery bypass graft/percutaneous coronary intervention (CABG/PCI), and vascular procedures during FY2006–2009 were modeled for the full sample of 501,489 patients and for at-risk subsamples with medical conditions alleviated by the procedures examined.

Results

Adjusting for demographic covariates and medical comorbidity, PTSD without depression was associated with decreased odds of all types of procedures (odds ratios [OR] range 0.74–0.82), as was depression without PTSD (OR range 0.59–0.77). In analyses of at-risk patients, those with PTSD only were less likely to undergo hip/knee (OR = 0.78) and vascular procedures (OR = 0.73) but not CABG/PCI. African-Americans and women at-risk patients were less likely to undergo hip/knee, vascular, and CABG/PCI procedures (OR range 0.31–0.82).

Conclusion

With the exception of CABG/PCI among at-risk patients, Veterans with PTSD and/or depression were less likely to undergo all types of procedures examined. Future studies should examine the reasons for this disparity and whether it is associated with subsequent adverse outcomes.     

The reinforcing effect of exercise in anorexia nervosa: Clinical correlates and relationship to outcome

ABSTRACT

The purpose of the current study was to examine the relative reinforcing effect of exercise compared to a non-monetary alternative reinforcer (leisure activity), and to money, before and after weight restoration in an inpatient population with anorexia nervosa (AN). Sixty-two inpatients with AN completed a progressive ratio (PR) task to earn exercise, leisure activities, or cash at low weight and after weight restoration. Measures of pathology and motivation to exercise were completed and post-treatment discharge weights were collected. Patients worked harder for exercise at low weight than after weight restoration (df = 46, t = 5.50, p < .001). PR task performance was weakly associated with a measure of commitment to exercise (low weight: r = 0.31, weight restored: r = 0.36, p < .05), but not with other clinical measures or follow-up weights. Contrary to prior suggestions, measurement of the reinforcing value of exercise among individuals with AN via a PR task does not appear valuable in assessing clinical severity or outcome. Other, simpler, self-report measures of commitment to exercise may have greater value in assessing these outcomes.     

Comorbidity of chronic insomnia with medical problems

STUDY OBJECTIVES: Determine the comorbidity of insomnia with medical problems. DESIGN: Cross-sectional and retrospective. PARTICIPANTS: Community-based population of 772 men and women, aged 20 to 98 years old. MEASUREMENTS: Self-report measures of sleep, health, depression, and anxiety. RESULTS: People with chronic insomnia reported more of the following than did people without insomnia: heart disease (21.9% vs 9.5%), high blood pressure (43.1% vs 18.7%), neurologic disease (7.3% vs 1.2%), breathing problems (24.8% vs 5.7%), urinary problems (19.7% vs 9.5%), chronic pain (50.4% vs 18.2%), and gastrointestinal problems (33.6% vs 9.2%). Conversely, people with the following medical problems reported more chronic insomnia than did those without those medical problems: heart disease (44.1% vs 22.8%), cancer (41.4% vs 24.6%), high blood pressure (44.0% vs 19.3%), neurologic disease (66.7% vs 24.3%), breathing problems (59.6% vs 21.4%), urinary problems (41.5% vs 23.3%), chronic pain (48.6% vs 17.2%), and gastrointestinal problems (55.4% vs 20.0%). When all medical problems were considered together, only patients with high blood pressure, breathing problems, urinary problems, chronic pain, and gastrointestinal problems continued to have statistically higher levels of insomnia than those without these medical disorders. CONCLUSION: This study demonstrates significant overlap between insomnia and multiple medical problems. Some research has shown it is possible to treat insomnia that is comorbid with select psychiatric (depression) and medical (eg, pain and cancer) disorders, which in turn increases the quality of life and functioning of these patients. The efficacy of treating insomnia in many of the above comorbid disorders has not been tested, indicating a need for future treatment research.     

Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase

The hemagglutinins of influenza viruses isolated from humans typically prefer binding to sialic acid in an alpha2,6 linkage. Presumably, the virus uses the presence of these receptors on the respiratory tract to gain entrance into the host cell. The ST6Gal I sialyltransferase knock-out mouse lacks the main enzyme necessary for the attachment of alpha2,6 sialic acid to N-linked glycoproteins on the cell surface. Yet even in the absence of detectable alpha2,6 sialic acid in the mouse respiratory tract, human influenza viruses can still infect these mice and grow to similar titers in the lung and trachea as compared to wild-type animals. This work demonstrates that the presence of a major alpha2,6 sialic acid on N-linked glycoproteins is not essential for human influenza virus infection in mice.     

Protecting children from the dangers of urban poverty

Exposure to the social ecology of poor urban neighborhoods significantly increases the incidence of traumatic stress disorders, placing children growing up in such neighborhoods at disproportionate risk. Although the risk factors for and effects of childhood complex traumatic stress disorders are well documented, there is little intervention research to guide the delivery of services to this population. This paper builds on current knowledge of childhood trauma and related treatments by introducing an intervention model using constructive family ritual functioning as a mechanism for increasing the protective function of the family. The intervention model postulates that use of family rituals as a coping resource will lead to decreased symptoms of chronic traumatic stress and rates of exposure to additional trauma.     

Integrating public health students into interprofessional education

ABSTRACT

Recognizing the public health professional are critical members of interprofessional teams, the Council on Education for Public Health (CEPH) recently added a required Masters of Public Health (MPH) student competency focused on interprofessional education (IPE). A student-centered approach to the design and evaluation of an emergency preparedness-focused curricular program to meet the interprofessional needs of MPH students was used to meet this expectation at the University of Washington. Curriculum design was informed by two 80-minute listening sessions with MPH students to better understand their current interprofessional educational experiences and needs, and how an emergency preparedness-focused two-hour Interprofessional Active Learning Series (iPALS) session could help them develop interprofessional competency. The resultant iPALS session was assessed with a short, paper-based questionnaire. We found MPH students have an interest in participating in IPE, and that all students who participated in the emergency preparedness-focused iPALS session reported significant increases in their interprofessional and disaster response abilities based on their pre- and post-session evaluations. Student-centered IPE curriculum focused on emergency preparedness can enhance the self-reported ability of students across the health sciences to perform on interprofessional teams while engaging in a topic that has relevance to MPH students.