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Methods: [11C]WAY100635, [18F]altanserin and positron emission tomography were used to compare 5-HT1A and 5-HT2A binding in MDD patients divided into eight past suicide attempters (>4yrs prior to scanning) and eight lifetime non-attempters, and both groups were compared to eight healthy volunteers.
Results: The two receptor types differed in binding pattern across brain regions from each other, but there were no differences in binding between healthy volunteers and the two depressed groups or between depressed suicide attempters and non-attempters. No effects of depression severity or lifetime aggression were observed for either receptor.
Conclusion: Limitations of this study include small sample size and absence of high lethality suicide attempts in the depressed attempter group. No trait-like binding correlations with past suicide attempt or current depression were observed. Given the heterogeneity of nonfatal suicidal behavior, a larger sample study emphasizing higher lethality suicide attempts may find the serotonin biological phenotype seen in suicide decedents. 相似文献
Methods: A cross-sectional prospective cohort study with 7-day follow-up was conducted. Body composition, cardiorespiratory fitness and biomarkers of cardiometabolic health were measured in thirty-three participants with SCI (> 1 year post injury). Physical activity dimensions were objectively assessed over 7-days.
Results: Activity energy expenditure (r =.43), physical activity level (r =.39), and moderate-to-vigorous physical activity (MVPA) (r =.48) were significantly (P < 0.001) associated with absolute (L/min) peak oxygen uptake (?O2 peak). ?O2 peak was significantly higher in persons performing ≥150 MVPA minutes/week compared to <40 minutes/week (P?=?0.003). Individual physical activity dimensions were not significantly associated with biomarkers of cardiometabolic health. However, body composition characteristics (BMI, waist and hip circumference) showed significant (P < 0.04), moderate (r >.30) associations with parameters of metabolic regulation, lipid profiles and inflammatory biomarkers. Relative ?O2 peak (ml/kg/min) was moderately associated with only insulin sensitivity (r?=?0.37, P?=?0.03).
Conclusions: Physical activity dimensions are associated with cardiorespiratory fitness; however, stronger and more consistent associations suggest that poor cardiometabolic health is associated with higher body fat content. Given these findings, the regulation of energy balance should be an important consideration for researchers and clinicians looking to improve cardiometabolic health in persons with SCI. 相似文献