Skeletal muscle (SM) is a large and physiologically important compartment. Adipose tissue is found interspersed between and within SM groups and is referred to as intermuscular adipose tissue (IMAT). The study objective was to develop prediction models linking appendicular lean soft tissue (ALST) estimates by dual-energy X-ray absorptiometry (DXA) with whole body IMAT-free SM quantified by magnetic resonance imaging. ALST and total-body IMAT-free SM were evaluated in 270 healthy adults [body mass index (BMI) of <35 kg/m(2)]. The SM prediction models were then validated by the leave-one-out method and by application in a new group of subjects who varied in SM mass [anorexia nervosa (AN), n = 23; recreational athletes, n = 16; patients with acromegaly, n = 7]. ALST alone was highly correlated with whole body IMAT-free SM [model 1: R(2) = 0.96, standard error (SE) = 1.46 kg, P < 0.001]; age (model 2: R(2) = 0.97, SE = 1.38 kg, P < 0.001) and sex and race (model 3: R(2) = 0.97, SE = 1.06 kg, both P < 0.001) added significantly to the prediction models. All three models validated in the athletes and patients with acromegaly but significantly (P < 0.01-0.001) over-predicted SM in the AN group as a whole. However, model 1 was validated in AN patients with BMIs in the model-development group range (n = 11; BMI of >16 kg/m(2)) but not in those with a BMI of <16 kg/m(2) (n = 12). The DXA-based models are accurate for predicting IMAT-free SM in selected populations and thus provide a new opportunity for quantifying SM in physiological and epidemiological investigations.

Background. Serotonin and brain-derived neurotrophic factor (BDNF) are known to be modulators of nociception. However, pain-related connection between yoga and those neuromodulators has not been investigated. Therefore, we aimed to evaluate the effect of yoga on pain, BDNF, and serotonin. Methods. Premenopausal women with chronic low back pain practiced yoga three times a week for 12 weeks. At baseline and after 12 weeks, back pain intensity was measured using visual analogue scale (VAS), and serum BDNF and serotonin levels were evaluated. Additionally, back flexibility and level of depression were assessed. Results. After 12-week yoga, VAS decreased in the yoga group (P < 0.001), whereas it increased (P < 0.05) in the control group. Back flexibility was improved in the yoga group (P < 0.01). Serum BDNF increased in the yoga group (P < 0.01), whereas it tended to decrease in the control group (P = 0.05). Serum serotonin maintained in the yoga group, while it reduced (P < 0.01) in the control group. The depression level maintained in the yoga group, whereas it tended to increase in the control group (P = 0.07). Conclusions. We propose that BDNF may be one of the key factors mediating beneficial effects of yoga on chronic low back pain.

It is well established that the genioglossus muscle (tongue protrudor) has a role in protecting or enhancing upper airway patency in individuals with obstructive sleep apnea. However, no investigation completed to date has addressed the role of the styloglossus and hyoglossus muscles (tongue retractors) in maintaining upper airway patency in humans. As a first step toward this goal, the present investigation was designed to examine the response of human tongue protrudor and retractor muscles during a breathhold maneuver and in steady-state hypoxic hypercapnia. The results showed that the protrudor and retractor muscles were coactivated under both conditions. Measurements of onset time of electromyographic activity during steady-state hypoxic hypercapnia revealed that phasic protrudor and retractor activity was initiated immediately before or during the early part of inspiration. We conclude that the tongue protrudor and retractor muscles are coactivated in response to hypoxia and hypercapnia, and that the tongue retractors may have a significant role in protecting upper airway patency during both apnea and hyperpnea.

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Background: Reduction malarplasty has been popular among Asians with a wide facial width. In general, malar setback after bony resection is regarded as the standard objective of reduction malarplasty. However, unnecessary bony resection may lead to various postoperative complications. Therefore, we suggest the use of reduction malarplasty without bony resection to achieve a similar narrowing effect of the facial width, based on radiographic analysis of malar arch movement. Patients and Methods: This retrospective study analyzed 48 patients with a wide midface who underwent reduction malarplasty between September 2018 and December 2019. We included 40 cases of advancement repositioning malarplasty (AR) without bony resection and 8 cases of setback reduction malarplasty (SR) with bony resection. The three-dimensional position of the malar arch expressed by coordinates (x, y, and z) on threedimensional computed tomography scans was used to compare the positional change between the surgical methods. The paired t-test, Wilcoxon text, and independent t-test were used in data analysis, and statistical analysis was performed using SPSS 23.0 software. Results: Medial and superior movement of the freed malar arch segment was significantly different between AR and SR (P < 0.05). Although medialization and superiorization were not significantly different between AR and SR, there was a significant difference in anterior-posterior movement between AR and SR (P < 0.05). Conclusion:The radiologic analysis based on malar arch movement between AR and SR showed similar narrowing effects on medialization and superiorization of the malar arch regardless of bony resection. Therefore, the AR can be effectively applied in case of arch dominant type or malar asymmetry. In addition, further comprehensive study including analysis on movement of facial soft tissue following malar bony movement is expected based on this study in near future.