scholarly journals Reconstitution of the complete rupture in musculotendinous junction using skeletal muscle-derived multipotent stem cell sheet-pellets as a “bio-bond”

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2231 ◽  
Author(s):  
Hiroyuki Hashimoto ◽  
Tetsuro Tamaki ◽  
Maki Hirata ◽  
Yoshiyasu Uchiyama ◽  
Masato Sato ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cell ◽  
Muscle Mass ◽  
Control Group ◽  
Short Term ◽  
Musculotendinous Junction ◽  
Multipotent Stem Cell ◽  
Recovery Group ◽  
Tetanic Tension

Background.Significant and/or complete rupture in the musculotendinous junction (MTJ) is a challenging lesion to treat because of the lack of reliable suture methods. Skeletal muscle-derived multipotent stem cell (Sk-MSC) sheet-pellets, which are able to reconstitute peripheral nerve and muscular/vascular tissues with robust connective tissue networks, have been applied as a “bio-bond”.Methods.Sk-MSC sheet-pellets, derived from GFP transgenic-mice after 7 days of expansion culture, were detached with EDTA to maintain cell–cell connections. A completely ruptured MTJ model was prepared in the right tibialis anterior (TA) of the recipient mice, and was covered with sheet-pellets. The left side was preserved as a contralateral control. The control group received the same amount of the cell-free medium. The sheet-pellet transplantation (SP) group was further divided into two groups; as the short term (4–8 weeks) and long term (14–18 weeks) recovery group. At each time point after transplantation, tetanic tension output was measured through the electrical stimulation of the sciatic nerve. The behavior of engrafted GFP+tissues and cells was analyzed by fluorescence immunohistochemistry.Results.The SP short term recovery group showed average 64% recovery of muscle mass, and 36% recovery of tetanic tension output relative to the contralateral side. Then, the SP long term recovery group showed increased recovery of average muscle mass (77%) and tetanic tension output (49%). However, the control group showed no recovery of continuity between muscle and tendon, and demonstrated increased muscle atrophy, with coalescence to the tibia during 4–8 weeks after operation. Histological evidence also supported the above functional recovery of SP group. Engrafted Sk-MSCs primarily formed the connective tissues and muscle fibers, including nerve-vascular networks, and bridged the ruptured tendon–muscle fiber units, with differentiation into skeletal muscle cells, Schwann cells, vascular smooth muscle, and endothelial cells.Discussion.This bridging capacity between tendon and muscle fibers of the Sk-MSC sheet-pellet, as a “bio-bond,” represents a possible treatment for various MTJ ruptures following surgery.

Skeletal and heart muscle protein turnover during long-term exposure to high environmental temperatures in young rats

2000 ◽  
Vol 78 (7) ◽  
pp. 557-564 ◽  
Author(s):  
S E Samuels ◽  
T A McAllister ◽  
J R Thompson
Keyword(s):  
Skeletal Muscle ◽  
Protein Synthesis ◽  
Muscle Mass ◽  
Protein Turnover ◽  
Muscle Protein ◽  
Control Group ◽  
Skeletal Muscle Protein ◽  
Protein Mass ◽  
Fractional Rate

A study was undertaken to determine the long-term effects of a hot environment on protein turnover in skeletal and cardiac muscles of young homeothermic animals. Three groups of 36 male 28 day old rats were housed at 35°C (hot group), 25°C (control group), or 25°C but pair-fed to the intake of the hot group (pair-fed group). Rates of protein synthesis and degradation were measured in vivo on days 5, 10, 15, and 20. By day 20, soleus and gastrocnemius (skeletal muscle) protein masses were 7 and 14% lower in the hot group and 31 and 21% lower in the pair-fed group compared with the control group (P < 0.05). The fractional rate of protein synthesis (ksyn) was on average 11% lower (P < 0.05) in the hot group compared with control rats and was not different from pair-fed rats. The fractional rate of skeletal muscle protein degradation (kdeg) in hot rats was slightly lower than in control rats; kdegwas on average 18% higher (P < 0.05) in the pair-fed group compared with the hot group and this difference appeared to be most prominent on day 5. In heart, by day 20, protein mass was 30% lower in the hot group and 40% lower in the pair-fed group compared with control rats (P < 0.05). ksynwas on average 19% lower (P < 0.05) in the hot group compared with the control group, but not different from pair-fed rats. In the heart there were no differences in kdegamong treatments. Plasma triiodothyronine (T3) concentration was lower in the hot group, but not in the pair-fed group, compared with controls. In conclusion, chronic exposure to hot environments was associated with lower skeletal and cardiac muscle mass and protein turnover; lower protein mass in this tissue was due to decreased ksyn; this is consistent with lower plasma T3concentrations. In pair-fed rats, ksynwas also reduced, but interestingly kdegwas not, resulting in a greater loss of skeletal muscle mass. These results suggest that heat exposure invokes physiological adaptations to preserve skeletal muscle mass despite decreased food intake. In the heart, loss of protein was a result of decreased ksyn, which can be primarily ascribed to lower food intake.Key words: protein synthesis, protein metabolism, acclimation, heat stress.

THE VALUE OF SKELETAL MUSCLE MASS IN PREDICTING SHORT-TERM OUTCOMES OF SURGICAL TREATMENT FOR KLATSKIN TUMOR

2018 ◽  
Vol 64 (5) ◽  
pp. 564-569
Author(s):  
Yuriy Zharikov ◽  
Tatyana Zharikova ◽  
Vladimir Nikolenko
Keyword(s):  
Skeletal Muscle ◽  
Surgical Treatment ◽  
Muscle Mass ◽  
Skeletal Muscle Mass ◽  
Negative Impact ◽  
Treatment Algorithm ◽  
Preoperative Treatment ◽  
Klatskin Tumor ◽  
Short Term ◽  
Oncological Patients

The objective of this review study was to analyze the relationship between skeletal muscle mass and postoperative short-term outcomes morbidity in patients with Klatskin tumor who underwent surgical treatment. Low index skeletal muscle mass had a negative impact factor on postoperative morbidity following resection of Klatskin tumor and should therefore be considered as preoperative risk assessment. The further study of body composition in oncological patients allowed revealing the group of patients with high probability of postoperative complications and this factor needed to be added to future models predictive scale of short-term outcomes with the aim of making the most rational preoperative treatment algorithm.

scholarly journals Efficacy of a bystander intervention for preventing dating violence in Brazilian adolescents: short-term evaluation

2019 ◽  
Vol 32 (1) ◽  
Author(s):  
Karine Brito dos Santos ◽  
Sheila Giardini Murta ◽  
Luis Gustavo do Amaral Vinha ◽  
Juliana Silva de Deus
Keyword(s):  
Romantic Relationships ◽  
Dating Violence ◽  
Control Group ◽  
Short Term ◽  
Brazilian Sample ◽  
Post Test ◽  
Short Term Evaluation ◽  
Term Evaluation ◽  
Brazilian Culture

Abstract Peers are the preferred source of help for Brazilian adolescents who experience dating violence. However, they are not always the best informants for effective responses for dealing with situations of violence in romantic relationships among peers. This experimental study aimed to evaluate the short-term efficacy of three aspects of a peer- and bystander approach-based intervention: the intent to offer help, empathy, and bystander attitudes in response to dating violence in a Brazilian sample of adolescents. The study’s participants were 33 adolescents randomized in two groups: experimental group (EG, n = 14) and control group (CG, n = 19). The EG underwent three weekly intervention sessions of 90 min each on the healthy versus violent romantic relationships, the quality of friendship in the peer network, and the role of the bystander, while the CG received no intervention. Evaluations were performed 1 week before and two and half months after the intervention. Statistically significant differences between EG and CG at post-test were not found in intention to help, empathy, and bystander attitudes. Future studies should include evaluations of larger samples and mid- and long-term follow-ups to identify patterns of change over the long term as well as examine barriers to utilization of bystander behaviors by adolescents in Brazilian culture.

scholarly journals Tail suspension is useful as a sarcopenia model in rats

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Akira Nemoto ◽  
Toru Goyagi
Keyword(s):  
Skeletal Muscle ◽  
Muscle Contraction ◽  
Experimental Model ◽  
Muscle Mass ◽  
Muscle Atrophy ◽  
Whole Body ◽  
Skeletal Muscle Atrophy ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Simple Method

Abstract Background Sarcopenia promotes skeletal muscle atrophy and exhibits a high mortality rate. Its elucidation is of the highest clinical importance, but an animal experimental model remains controversial. In this study, we investigated a simple method for studying sarcopenia in rats. Results Muscle atrophy was investigated in 24-week-old, male, tail-suspended (TS), Sprague Dawley and spontaneously hypertensive rats (SHR). Age-matched SD rats were used as a control group. The skeletal muscle mass weight, muscle contraction, whole body tension (WBT), cross-sectional area (CSA), and Muscle RING finger-1 (MuRF-1) were assessed. Enzyme-linked immunosorbent assay was used to evaluate the MuRF-1 levels. Two muscles, the extensor digitorum longus and soleus muscles, were selected for representing fast and slow muscles, respectively. All data, except CSA, were analyzed by a one-way analysis of variance, whereas CSA was analyzed using the Kruskal-Wallis test. Muscle mass weight, muscle contraction, WBT, and CSA were significantly lower in the SHR (n = 7) and TS (n = 7) groups than in the control group, whereas MuRF-1 expression was dominant. Conclusions TS and SHR presented sarcopenic phenotypes in terms of muscle mass, muscle contraction and CSA. TS is a useful technique for providing muscle mass atrophy and weakness in an experimental model of sarcopenia in rats.

630 IMPACT OF LOW SKELETAL MUSCLE MASS AND DENSITY ON OUTCOMES OF LOCALLY ADVANCED ESOPHAGEAL CANCER PATIENTS TREATED WITH RADICAL RADIOTHERAPY

2021 ◽  
Vol 34 (Supplement_1) ◽  
Author(s):  
Yuan Wang ◽  
Ningjing Yang ◽  
Hongyuan Jia ◽  
Long Liang ◽  
Lei Wu ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Esophageal Cancer ◽  
Muscle Mass ◽  
Skeletal Muscle Mass ◽  
Mass Density ◽  
Locally Advanced ◽  
Radical Radiotherapy ◽  
Term Survival ◽  
Locally Advanced Esophageal Cancer

Abstract   Low skeletal muscle mass and density are independent predictors of clinical outcomes in multiple gastrointestinal cancers. However, its effect on the long-term survival of locally advanced esophageal cancer patients undergoing radical radiotherapy is still unclear. Methods Patients with stage II-III esophageal cancer undergoing radical radiotherapy, enrolled in a observational cohort study, were included. Skeletal muscle mass and density were measured on CT. Patients with high and low skeletal muscle mass and density were compared regarding overall survival (OS). Results 165 patients (75.8% males, median age 63) were included, from March-2012 to September-2017. Before radiotherapy, 26.7% patients had low skeletal-muscle-mass and 23.0% patients had low skeletal-muscle-density. After radiotherapy, 40.6% patients had low skeletal-muscle-mass and 30.3% patients had low skeletal-muscle-density.The median OS of high skeletal-muscle-mass/density group was significantly higher than that of low skeletal-muscle-mass/density group before radiotherapy (28.7 vs 28.2 months, p = 0.041; 29.6 vs 16.9 months, p = 0.025). The median OS of high skeletal-muscle-mass/density group was also significantly higher than that of low skeletal-muscle-mass/density group after radiotherapy (30.3 vs 20.3 months, P = 0.012; 29.6 vs 17.2 months, p = 0.018). Conclusion Low skeletal muscle mass and density are associated with long-term outcome in patients undergoing radical radiotherapy. It is suggested that oncologists should pay more attention to the management of muscle mass and density of patients with esophageal cancer undergoing radiotherapy in order to improve their nutritional status and long-term survival.

scholarly journals Evaluation of the Policy Effect of China’s Environmental Interview System for Effective Air Quality Governance

2021 ◽  
Vol 18 (17) ◽  
pp. 9006
Author(s):  
Xue Jin ◽  
Ussif Rashid Sumaila ◽  
Kedong Yin ◽  
Zhichao Qi
Keyword(s):  
Air Quality ◽  
Environmental Protection ◽  
Environmental Sustainability ◽  
Local Governments ◽  
Local Governance ◽  
Assessment System ◽  
Control Group ◽  
Short Term ◽  
Interview System

The Ministry of Ecology and Environment of the People’s Republic of China formally proposed an environmental interview system in May 2014, which applies pressure on local governments to fulfill their responsibility toward environmental protection by conducting face-to-face public interviews with their officials. In this paper, 48 cities that were publicly interviewed from 2014–2020 were considered the experimental group and 48 cities surrounding them were the control group. First, the dynamic panel model is applied to initially determine the effect of the policy. Then, a regression discontinuity method (Sharp RD) is used to analyze the short-term and long-term effects and compare the reasons for the differences observed among the estimates of various types of samples. Finally, a series of robustness tests were also conducted. The results show that the environmental interview system can improve air quality. However, because an emergency short-term local governance system exists at present, the governance effect is not long-term and, therefore, not sustainable. Therefore, it suggests that the government should continue to improve the environmental interview system, establish an optimal environmental protection incentive mechanism, and encourage local governments to implement environmental protection policies effectively in the long term. The results of the research are of great significance to the environmental impact assessment system of the world, especially in countries with similar economic systems, which are facing a trade-off between economic growth and environmental sustainability.

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