Skeletal Muscle Quality Assessment in Patients With Cardiac Disease Associated With Type 2 Diabetes Mellitus: A Pilot Study.

Background Type 2 diabetes mellitus (T2DM) is associated with changes in skeletal muscle quantity and quality, such as increased ectopic fat. Cardiac rehabilitation (CR) aims to improve the exercise capacity and muscle strength. This study aimed to determine the relationship between qualitative changes in the skeletal muscles and exercise function in patients with and without diabetes mellitus. Methods The study included patients with cardiovascular diseases who entered CR. Of 72 CR patients (68.1±9.0 years) who underwent a cardiopulmonary exercise test and skeletal muscle assessment at discharge, 15 patients with T2DM and 15 without DM were selected using propensity score matching by age and gender. Results No significant differences in the skeletal muscle echo intensity (EI) (T2DM: 58.4, Non-DM: 53.4, p=0.32), skeletal muscle index (T2DM: 7.5 kg/m2, Non-DM: 7.2 kg/m2, p=0.36), or the weight-bearing index (WBI)(T2DM: 0.44, Non-DM: 0.50, p=0.35) existed between the two groups. The phase angle (PhA) (T2DM: 3.67°, Non-DM: 4.49°, p<0.05) and peak oxygen uptake (T2DM: 12.3 mL/kg/min, Non-DM: 14.8 mL/kg/min, p<0.05) were significantly lower in the T2DM group. PhA values showed a significant correlation with the WBI, a parameter of lower limb muscle strength (r=0.50, p<0.05). Conclusion The coexistence of cardiovascular disease and T2DM resulted in a decrease in the PhA, indicating a qualitative decrease in skeletal muscle mass. The PhA is also associated with lower limb muscle strength.

Relationship Between Increased Oxygen Uptake and Lactate Production With Progressive Incremental Electrode Skeletal Muscle Stimulation: A Pilot Study.

Background Belt electrode skeletal muscle stimulation (B-SES) is an alternative exercise therapy for those with difficulty performing voluntary exercise. However, it is unknown whether oxygen uptake (VO2) in B-SES is comparable to cardiopulmonary exercise test (CPX) as assessed by voluntary exercise. This study aimed to evaluate oxygen uptake (VO2) and lactate (LA) production in incremental B-SES compared to ergometer CPX and to determine the relationship with ergometer CPX. Methods This study included 10 healthy young Japanese participants. Using a crossover design, all participants underwent incremental B-SES CPX and ergometer CPX using a 20 W ramp. Serum lactic acid concentration (LA) was measured serially before, during, and after B-SES. The tolerability of B-SES was adjusted with the change in LA level (⊿LA). Results Peak VO2 during B-SES (14.1±3.3 mL/kg/min) was significantly lower than ergometer peak VO2 (30.2±6.2 mL/kg/min, P<0.001). B-SES peak VO2 was similar to the anaerobic threshold (AT) VO2 on ergometer CPX (15.1±2.6 mL/kg/min). LA (Rest: 1.4±0.3, Peak: 2.8±0.8 mmol) and plasma noradrenalin (Rest: 0.2±0.1, Peak: 0.4±0.1 ng/mL) levels increased after B-SES. No significant correlation was observed between B-SES peak VO2 and ergometer CPX. However, after adjusting for B-SES, tolerability, it (peak VO2 of B-SES /⊿LA) correlated with peak VO2 (r=0.688, p=0.028) on the ergometer. Conclusion Peak VO2 of the passively progressive B-SES almost reached the AT value of the ergometer CPX without adverse events. Peak VO2 of B-SES adjusted with ⊿LA may be used to predict peak VO2 in ergometer CPX.

Enrichment of transplantable germ cells in salmonids using a novel monoclonal antibody by magnetic-activated cell sorting.

In the fish germ cell transplantation system, only type A spermatogonia (ASGs) and oogonia are known to be incorporated into the recipient genital ridges, where they undergo gametogenesis. Therefore, high colonization efficiency can be achieved by enriching undifferentiated germ cells out of whole testicular cells. In this study, we used magnetic-activated cell sorting (MACS) for enriching undifferentiated germ cells of rainbow trout using a monoclonal antibody that recognizes a specific antigen located on the germ cell membrane. We screened the antibodies to be used for MACS by performing immunohistochemistry on rainbow trout gonads. Two antibodies, nos. 172 and 189, showed strong signals for ASGs and oogonia. Next, we performed MACS with antibody no. 172 using gonadal cells isolated from vasa-gfp rainbow trout showing GFP in undifferentiated germ cells. We found that GFP-positive cells are highly enriched in antibody no. 172-positive fractions. Finally, to examine the transplantability of MACS-enriched cells, we intraperitoneally transplanted sorted or unsorted cells into recipient larvae. We observed that transplantability of sorted cells, particularly ovarian cells, were significantly higher than that of unsorted cells. Therefore, MACS with antibody no. 172 could enrich ASGs and oogonia and become a powerful tool to improve transplantation efficiency in salmonids.