Trastornos musculoesqueléticos y dolor asociados a exigencias laborales en pescadores de mediana escala de Yucalpetén, Yucatán, México / Musculoskeletal disorders and pain associated with demands work in medium-scale fishermen from Yucalpetén, Yucatán, México

Los pescadores suelen ejercer su actividad en altamar en condiciones precarias y sometidos a diversas exigencias de trabajo que con el tiempo derivan en diversos daños a la salud entre los que se encuentran los trastornos musculoesqueléticos (TME), los cuales se reportan a nivel mundial, como la principal causa de discapacidad y jubilaciones anticipadas. Objetivo: Identificar las exigencias laborales, daños musculoesqueléticos y dolor asociados a la actividad laboral de los pescadores en Progreso, Yucatán, México, con la intención de visibilizar y generar evidencia empírica en materia laboral en trabajadores de este sector, ante la carencia de información, pese a que es una de las actividades más peligrosas en el mundo. Materiales y Métodos: Estudio descriptivo, analítico y transversal. Participaron 134 pescadores a los que se les aplicó una encuesta individual, previo consentimiento informado. Las variables se analizaron y controlaron en el programa JMP versión 15, con un nivel de significancia menor a p<0.05 y un intervalo de confianza del 95%. Resultados: Las principales exigencias que se señalan son posturas forzadas y movimientos repetitivos. Las zonas del cuerpo más afectadas, espalda, cintura y caderas (44%), miembros superiores (40%), inferiores (30%) y cuello (17%). Conclusión: Los resultados evidencian la relación de los trastornos musculoesqueléticos con las exigencias laborales. Se destaca la presencia de dolor en espalda baja, hombros y cuello. por lo que es necesario implementar programas de capacitación y evaluación ergonómica sobre posturas y cargas, así como programas de rehabilitación a corto plazo(AU)

Fishermen usually carry out their activity on the high seas in precarious conditions and subject to various work demands that over time lead to various health damages, among which are musculoskeletal disorders (MSDs), which are reported worldwide, such as the leading cause of disability and early retirement. Objective: Identify labor demands, musculoskeletal damages problems and pain associated with the work activity of fishermen in Progress, Yucatán, México, with the intention of making visible and generating empirical evidence on labor matters in workers in this sector, given the lack of information, despite the fact it is one of the most dangerous activities in the world. Materials y Methods: Descriptive, analytical and cross-sectional study. 134 fishermen participated to whom an individual survey was applied, with prior informed consent. The variables were analyzed and controlled in the program JMP version 15, with a significance level of less than p<0.05 and a 95% confidence Interval. Results: The main demands that are pointed out are forced postures and repetitive movements. The most affected areas of the body: back, waist and hips (44%), upper limbs (40%) lower limbs (30%) and neck (17%). The results show the relationship between musculoskeletal disorders with work demands. Conclusions: The presence of pain in the lower back, shoulders and neck stands out. Therefore, it is necessary to implement ergonomic training and evaluation programs on postures and loads, as well as short-term rehabilitation programs(AU)

The correlation between degree of multifidus muscle atrophy and severity in patients with degenerative lumbar spondylolisthesis / 中华骨科杂志

Objective To investigate the correlation between degree of multifidus muscle atrophy and severity in patients with degenerative lumbar spondylolisthesis.Methods A total of 103 patients with lumbar degenerative spondylolisthesis were retrospectively analyzed,including 22 male patients (21.4％) and 81 female patients (78.6％).There were 2 cases of L2 spondylolisthesis,10 cases of L3 spondylolisthesis,81 cases of L4 spondylolisthesis,and 10 cases of L5 spondylolisthesis.The average age was 58.55 ±0.88 years old.Each patient underwent lumbar lateral X-ray,and lumbar MRI,and the imaging data were collected.MRI images were obtained to measure and calculatethe ratio of the fat-free multifidus muscle cross sectional area to total multifidus muscle cross sectional area (LCSA/TCSA) in slipped segments and non-slipped segments.Lumbar lateral radiographs were obtained to measure and calculate slipped ratio.All data were analyzed by SPSS 23.0.Paired-samples T test was carried out to investigate whether there were LCSA/TCSA differences between in slipped segments and non-slipped segments.The correlation between LCSA/TCSA in slipped segments and slipped ratio was analyzed by using Pearson correlation coefficient system.P=0.000 was considered statistically significant.Results The degree of multifidus muscle atrophy (FCSA/TCSA) in the upper non-spondylolisthesis segments and the multifid muscle atrophy (FCSA/TCSA) in the degenerative spondylolisthesis segments (t=-12.618,P=0.000).there was significant difference between them.The degree of multifidus muscle atrophy (FCSA/TCSA) of degenerative spondylolisthesis was correlated with the spondylolisthesis ratio,and the correlation coefficient was-0.425.There was a high negative correlation between FCSA/TCSA ratio and spondylolisthesis ratio of degenerative spondylolisthesis.Conclusion The degree of multifidus muscle atrophy in degenerative spondylolisthesis is more serious than that in the upper non-spondylolisthesis segments,and there is a positive correlation between the degree of multifidus muscle atrophy in degenerative lumbar spondylolisthesis and the degree of lumbar spondylolisthesis in degenerative lumbar spondylolisthesis patients.

The correlation between degree of multifidus muscle atrophy and severity in patients with degenerative lumbar spondylolisthesis / 中华骨科杂志

Objective@#To investigate the correlation between degree of multifidus muscle atrophy and severity in patients with degenerative lumbar spondylolisthesis.@*Methods@#A total of 103 patients with lumbar degenerative spondylolisthesis were retrospectively analyzed, including 22 male patients (21.4%) and 81 female patients (78.6%). There were 2 cases of L2 spondylolisthesis, 10 cases of L3 spondylolisthesis, 81 cases of L4 spondylolisthesis, and 10 cases of L5 spondylolisthesis. The average age was 58.55 ±0.88 years old. Each patient underwent lumbar lateral X-ray, and lumbar MRI, and the imaging data were collected. MRI images were obtained to measure and calculatethe ratio of the fat-free multifidus muscle cross sectional area to total multifidus muscle cross sectional area (LCSA/TCSA) in slipped segments and non-slipped segments. Lumbar lateral radiographs were obtained to measure and calculate slipped ratio. All data were analyzed by SPSS 23.0. Paired-samples T test was carried out to investigate whether there were LCSA/TCSA differences between in slipped segments and non-slipped segments. The correlation between LCSA/TCSA in slipped segments and slipped ratio was analyzed by using Pearson correlation coefficient system. P=0.000 was considered statistically significant.@*Results@#The degree of multifidus muscle atrophy (FCSA/TCSA) in the upper non-spondylolisthesis segments and the multifid muscle atrophy (FCSA/TCSA) in the degenerative spondylolisthesis segments (t=-12.618, P=0.000). there was significant difference between them. The degree of multifidus muscle atrophy (FCSA/TCSA) of degenerative spondylolisthesis was correlated with the spondylolisthesis ratio, and the correlation coefficient was -0.425. There was a high negative correlation between FCSA/TCSA ratio and spondylolisthesis ratio of degenerative spondylolisthesis.@*Conclusion@#The degree of multifidus muscle atrophy in degenerative spondylolisthesis is more serious than that in the upper non-spondylolisthesis segments, and there is a positive correlation between the degree of multifidus muscle atrophy in degenerative lumbar spondylolisthesis and the degree of lumbar spondylolisthesis in degenerative lumbar spondylolisthesis patients.

Effects of neuromuscular electrical stimulation on muscle atrophy and muscle fiber composition in quadriceps muscles of chronic obstructive pulmonary disease rats / 中华老年医学杂志

Objective To investigate the effect of neuromuscular electrical stimulation(NMES) on muscle atrophy and muscle fiber type conversion in quadriceps muscles of rats with chronic obstructive pulmonary disease(COPD).Methods Forty-eight male SPF Wistar rats were randomly divided into three groups:the healthy control group,COPD model group and NMES treatment group,with sixteen rats in each group.Rats in the NMES treatment group were given alternating electrical stimulation at 100 Hz and 2 Hz,with each stimulation time of 30 min,7 days per week,for 4 weeks.The control group and the COPD model group were only treated with electrode sheets.After the intervention,the endurance running distance measurement,the pathological changes of rat quadriceps muscle detected by HE staining,the mRNA and protein content of MSTN,MyHC(Myosin Heavy Chain)-Ⅰ,MyHC-Ⅱ a and MyHC-Ⅱ x in quadriceps muscles determined by Realtime PCR and Western Blot were performed.Results Compared with the healthy control group,the cross-sectional area,endurance running distance and MyHC-Ⅰ mRNA and protein expressions in the quadriceps muscles were decreased[(654.7±53.7) μm2 vs.(1079.8±117.2) μm2,(396.7±42.4) m vs.(607.4 ±56.3) m,0.407 ± 0.054 vs.0.997 ± 0.069,0.884 ± 0.102 vs.1.723 ± 0.156,t =4.642,3.785,24.723 and 18.640,P =0.008,0.033,0.000 and 0.000,respectively],while MSTN,MyHC-Ⅱ a and MyHC-Ⅱx mRNA and protein expressions were increased in the COPD model group (all P ＜ 0.01)Compared with COPD model,the cross-sectional area (997.5 ± 92.4 μm2),endurance running distance(597.2±65.8 m)and the expression levels of MyHC-Ⅰ mRNA(0.884±0.097)and protein (1.534±0.182)in the quadriceps muscles were increased(t =3.734,3.602,19.988 and 13.666,P =0.035,0.043,0.000,0.000),and the mRNA and protein expression levels of MSTN,MyHC-Ⅱ a and MyHC-Ⅱ x were decreased in the NMES treatment group(all P ＜0.01).Further correlation analysis found that the protein expression of MSTN in the quadriceps muscles was negatively correlated with muscle cross-sectional area,MyHC-Ⅰ protein levels and endurance running distance(r =-0.724,0.426 and-0.536,P =0.002,0.036 and 0.007,respectively),and positively correlated with the protein expressions of MyHC-Ⅱ a and MyHC-Ⅱ x(r=0.408 and 0.392,P =0.042 and 0.048).Conclusions The expression of MSTN is increased in quadriceps muscle of COPD rats,and NMES can inhibit the expression of MSTN in quadriceps muscles.MSTN is associated with muscle atrophy and muscle fiber conversion in COPD.Inhibition of MSTN expression can improve muscle atrophy and reverse muscle fiber transformation.

Mechanism and clinical research advance of muscle atrophy: thinking based on the 65th Annual Meeting of American College of Sports Medicine / 中国组织工程研究

BACKGROUND: The purpose of this study was to introduce the mechanism and clinical application of muscular atrophy that is a hotspot in the 65th Annual Meeting of American College of Sports Medicine and the 9th World Conference on Exercise Is Medicine and the World Conference of Basic Science of Muscle Hypertrophy and Atrophy. OBJECTIVE: To summarize and analyze the frontiers and hotspots of research findings on muscular atrophy, in order to provide new ideas for further research of exercise improving muscle function and the mechanism and application in this field, and provide a reference for the study on sports science, sports medicine, and sports rehabilitation in China. METHODS: Related reports and cutting-edge research findings in 65th Annual Meeting of American College of Sports Medicine were collected. Meanwhile, PubMed database between January 1993 and August 2018 was retrieved. The keywords were "skeletal muscle, muscle atrophy, movement and muscle, resistance movement". Thirty-five articles related to the molecular mechanism and clinical application of muscle atrophy were included for analysis and discussion. RESULTS AND CONCLUSION: The World Congress is a unique opportunity to bring together interdisciplinary investigators for the most comprehensive meeting ever held on this topic. The program will include a keynote lecture, tutorials, and symposia from leading experts. The meeting focused on the intrinsic and extrinsic variables that regulate skeletal muscle hypertrophy and atrophy. How exercise brings about skeletal muscle atrophy and its application in clinical problems such as aging, disease, injury, chronic diseases, and how these changes may relate to chronic disease were discussed as well. The research on muscle hypertrophy is mostly concentrated in the field of competitive sports.

Effect of comprehensive functional exercise on intubation after offline inpatients with severe muscle atrophy / 中国实用护理杂志

Objective To explore the effect of comprehensive functional exercise on re-intubation in hospitalized patients with critical muscle wasting. Methods A total of 92 patients with severe muscle atrophy who were treated in our hospital from January 2016 to 2018 were selected. According to the nursing method, the patients were divided into two groups, including 46 cases in the control group, routine muscle atrophy exercise, and 46 cases in the observation group. Comprehensive functional exercise was performed on the basis of the control group. The control group took regular muscle atrophy exercises, and the observation group took a comprehensive functional exercise on the basis of the control group. The reintubation rates at 48h, 72h, and 168h after extubation were compared between the two groups; the incidence of crisis, ventilator prevalence, occurrence rate, and off-line time were compared between the two groups; the health status of SF-36 was compared between the two groups. Results There were 0, 1, and 2 patients in the observation group at 48, 72, and 168h, and 5, 10, and 13 patients in the control group, respectively, with statistically significant differences (χ2=5.287, 8.364, 9.478, P < 0.05 or 0.01). The incidence rate of crisis, ventilator probability and complication rate were 8.70% (4/46), 4.35% (2/46) and 4.35% (2/46) in the observation group, and 23.91% (11/46), 30.23% (13/46) and 19.57% (9/46) in the control group, respectively. The difference was statistically significant ( χ2=8.791, 9.478, 7.325, P<0.05). The off-line time of the observation group was (107.22 ±10.98) h, and that of the control group (199.44 ± 10.57) h, with statistically significant difference (t=2.413, P<0.05). The SF-36 health status score of the observation group was respectively 36.12±10.44, 82.20±10.24, 40.43±16.14, 63.88±9.75, 82.06±10.11, and the control group was 26.68 ± 17.66, 26.78 ± 10.72, 42.18 ± 8.79, and 68.92 ± 9.65. The difference between the two groups was statistically significant (t=12.214- 14.829, P＜0.05). Conclusions Comprehensive functional exercise is beneficial to reduce the rate of intubation of patients with severe muscle atrophy, reduce the incidence of adverse events and improve the health of patients.

Effect of comprehensive functional exercise on intubation after offline inpatients with severe muscle atrophy / 中国实用护理杂志

Objective@#To explore the effect of comprehensive functional exercise on re-intubation in hospitalized patients with critical muscle wasting.@*Methods@#A total of 92 patients with severe muscle atrophy who were treated in our hospital from January 2016 to 2018 were selected. According to the nursing method, the patients were divided into two groups, including 46 cases in the control group, routine muscle atrophy exercise, and 46 cases in the observation group. Comprehensive functional exercise was performed on the basis of the control group. The control group took regular muscle atrophy exercises, and the observation group took a comprehensive functional exercise on the basis of the control group. The reintubation rates at 48h, 72h, and 168h after extubation were compared between the two groups; the incidence of crisis, ventilator prevalence, occurrence rate, and off-line time were compared between the two groups; the health status of SF-36 was compared between the two groups.@*Results@#There were 0, 1, and 2 patients in the observation group at 48, 72, and 168h, and 5, 10, and 13 patients in the control group, respectively, with statistically significant differences (χ2=5.287, 8.364, 9.478, P < 0.05 or 0.01). The incidence rate of crisis, ventilator probability and complication rate were 8.70% (4/46), 4.35% (2/46) and 4.35% (2/46) in the observation group, and 23.91% (11/46), 30.23% (13/46) and 19.57% (9/46) in the control group, respectively. The difference was statistically significant (χ2=8.791, 9.478, 7.325, P < 0.05). The off-line time of the observation group was (107.22 ±10.98) h, and that of the control group (199.44 ±10.57) h, with statistically significant difference (t=2.413, P < 0.05). The SF-36 health status score of the observation group was respectively 36.12±10.44, 82.20±10.24, 40.43±16.14, 63.88±9.75, 82.06±10.11, and the control group was 26.68±17.66, 26.78±10.72, 42.18±8.79, and 68.92±9.65. The difference between the two groups was statistically significant (t=12.214-14.829, P<0.05).@*Conclusions@#Comprehensive functional exercise is beneficial to reduce the rate of intubation of patients with severe muscle atrophy, reduce the incidence of adverse events and improve the health of patients.

Assessment and clinical management of sarcopenia in patients with liver cirrhosis / 临床肝胆病杂志

As the disease progresses, there is a significant change in the body composition of patients with liver cirrhosis, and sarcopenia is one of the common complications in liver cirrhosis, especially in decompensated cirrhosis. About 30%-70% of patients with liver cirrhosis have sarcopenia, which greatly affects patients’ survival and is closely associated with the development of hepatic encephalopathy. Sarcopenia may also increase the risk of infection. Sarcopenia and muscle fatty degeneration can be used as poor prognostic indicators of hepatocellular carcinoma and may increase the risk of recurrence of liver cancer. This article reviews the research advances in the definition of sarcopenia, the association of sarcopenia with liver cirrhosis, and assessment and clinical management of sarcopenia.

Study on denervated rat skeletal muscle by 7.0 T 31P-MR phosphorus spectroscopy / 中华放射学杂志

Objective@#To investigate the changes of 31P-MRS in denervated skeletal muscle at 7.0 T MR system.@*Methods@#In the experiment group, a total of 18 male Sprague-Dawley rats aged 6-8 weeks old and weighing 200-250 g were obtained. The right posterior femoral nerve were transected, and the proximal stumps were ligated by using 5-0 nylon stitches to preclude spontaneous repair. A sham surgery (incision and exploration of the nerve) was performed at the same time (n=6). Before rat model established and at varying times after initial surgery (3 d, and 1, 2, 4, 6, and 8 weeks). 31P-MR spectra of rat quadriceps femoris were acquired on 7.0 T Agilent small animal MR imaging system. We quantified the phosphocreatine (PCr), adenosine triphosphate(β-ATP), and inorganic phosphate (Pi) using Creatine phosphate disodium salt(10 mmol/L) as an external standard. The ratios, include PCr/Pi, Pi/β-ATP, PCr/β-ATP, PCr/(PCr+Pi) and Pi/(PCr+Pi) were quantified in jMRUI. All data were analyzed by one way analysis of variance (ANOVA) with posttest inter-group comparisons using Bonferroni test. Comparative analysis methods between the experimental and control group were performed via independent samples t test. P<0.05 was considered as statistically significance.@*Results@#The average measured concentrations of β-ATP, PCr, and Pi in control groups were (6.654±0.178) μmol/g, (25.656±0.738) μmol/g, and (1.594±0.096) μmol/g, respectively. There were significant statistically differences in β-ATP, PCr, Pi, PCr/Pi, PCr/PCr+Pi,Pi/PCr+Pi between the study and control group(P<0.05) at any measurement time point after denervation. Pi/β-ATP,PCr/β-ATP and pHi in the experimental group significantly statistically differed from those of the control group (all P<0.05)at each time point except on day 3 after operation. The total concentrations of β-ATP and PCr were reduced by 11.5% and 19.7% respectively on day 3. Thereafter, β-ATP and PCr declined rapidly by 63.1% and 68.8% at week 4 respectively, then decreased slowely by 74.0%和82.3% till week 10. The change of PCr/Pi is similar to β-ATP and PCr, but more remarkable. Pi, Pi/PCr+Pi, Pi/ATP showed a progressively increase till week 10. The intra-cellular pH (pHi) of normal rat muscles was 7.033±0.017, While the pHi gently in experiment rat muscles decreased during the entire experiment.@*Conclusion@#31P-MRS with 7.0 T can quantify the temporal changes of energy metabolism and pHi in normal and denervated rat muscles. It shows that the dysfunction of energy metabolism are progressive with time and that they begin within a short period following the nerve section, the change of β-ATP, PCr, PCr/Pi take place primarily within 4 weeks after denervation. β-ATP, PCr, and PCr/Pi may be potential biomarkers of energy metabolism in the evaluation of denervated muscle atrophy.

Pedigree analysis of DYNC1H1 p. P776L mutation in a family with spinal muscular atrophy / 中华神经科杂志

Objective To analyze the clinical and electrophysiological features in a family with spinal muscular atrophy (SMA), and assess the probable causative gene mutations for the family. Methods To identify the nosogenesis of the proband with weakness and atrophy in the double lower proximal limbs, clinical data of his 12 family members were collected, and the proband and his mother were selected for clinical examinations, including laboratory tests, electromyogram (EMG), F-wave, H-reflex, X-ray of the spine and double lower limbs, brain and spinal cord magnetic resonance imaging, etc. Moreover, human whole exome sequencing was performed on blood sample from the proband, then its deleterious effects were assessed according to the Standards and guidelines for the interpretation of sequence variants, a joint consensus recommendation of the American College of Medical Genomics (ACMG) and the Association for Molecular Pathology (AMP). Subsequently, the strong pathogenic mutation was validated by Sanger sequencing. Results Familial investigation showed seven of 12 family members presented with weakness in the double lower proximal limbs. Among them, three had the main manifestation of atrophy in the double lower proximal limbs, one had high arched foot as the main presentation, and the others had weakness in the double lower proximal limbs. EMG studies showed the abnormal results in the anterior horn of the spinal cord. The strong pathogenic mutation in DYNC1H1 gene (exon8, c.2327C＞T, p.P776L) was identified from the proband according to ACMG and AMP guidelines. Sanger sequencing revealed six patients had this variant and it was passed mainly from his maternal grandmother. Conclusions A pathogenic mutation of the DYNC1H1 p.P776L in six Chinese pedigrees which cosegregated with SMA was identified. There existed individual differences in clinical presentations. This finding may have important implications for the study of SMA in Chinese patients.

Oral creatine supplementation attenuates muscle loss caused by limb immobilization: a systematic review / Suplementação oral de creatina atenua a perda de massa muscular causada pela imobilização de membros: uma revisão sistemática

Abstract Introduction: Recent studies have pointing creatine supplementation as a promising therapeutic alterna- tive in several diseases, especially myopathies and neurodegenerative disorder. Objective: elucidate the role of creatine supplementation on deleterious effect caused by limb immobilization in humans and rats. Methods: Analyzed articles were searched by three online databases, PubMed, SportDicus e Scielo. After a review and analysis, the studies were included in this review articles on effect of creatine supplementation on skeletal muscle in humans and rat, before, during and after a period of limb immobilization. Results: Studies analyzed demonstrated positive points in use of creatine supplementation as a therapeutic tool to mitigating the deleterious effects of limb immobilization, in humans and rat. Conclusion: The dataset of this literature review allows us to conclude that creatine supplementation may reduce muscle loss and/or assist in the recovery of muscle atrophy caused by immobilization and disuse in rats and humans. Also, we note that further research with better methodological rigor is needed to clarify the mechanisms by which creatine support the recovery of muscle atrophy. Moreover, these effects are positive and promising in the field of muscle rehabilitation, especially after member's immobilization.

Resumo Introdução: Estudos recentes apontam a suplementação de creatina como promissora alternativa terapêuti- ca em desordens de diversos tipos, especialmente miopatias e desordens neurodegenerativas. Objetivo: Essa revisão tem o objetivo de elucidar o papel da creatina sobre a perda da massa muscular causada pela imobili- zação de membros em seres humanos e ratos. Métodos: Os artigos analisados foram buscados em três bases de dados on-line, PubMed, SportDiscus e Scielo. Após análise dos estudos, foram incluídos na presente revisão os efeitos da suplementação de creatina na musculatura esquelética, envolvendo seres humanos e roedores, antes, durante e depois de um período de imobilização e desuso. Resultados: Os estudos analisados apresentaram pontos positivos sobre a utilização de creatina, sobretudo quando combinado com outro recurso terapêutico, atenuando a atrofia muscular causada pela imobilização de membros. Conclusão: Em suma, o conjunto de dados ainda que limitantes apresentado por essa revisão de literatura nos permite concluir que a suplemen- tação com creatina é capaz de amenizar a perda de massa muscular e/ou auxiliar na recuperação da atrofia muscular causada pela imobilização e desuso em ratos e humanos. Ainda, salientamos que mais investigações com melhor rigor metodológico são necessárias para o esclarecimento sobre os mecanismos pelo qual a creati- na favorece a recuperação da atrofia muscular. Alem disso, esses efeitos são positivos e promissores na área da reabilitação muscular, especialmente após a imobilização de membros.

Fasudil blocks muscle atrophy and C2C12 myoblasts respiratory dysfunction triggered by ROCK1 / 第二军医大学学报

Objective To confirm whether fasudil can block C2C12 myoblasts respiration dysfunction triggered by Rho-associated coiled-coil containing protein kinase 1 (ROCK1), and whether it can block the occurrence of muscle atrophy. Methods C2C12 myoblasts were cultured in vitro, and 2% horse serum was used to induce cell differentiation and maturation. The obtained mature muscle tubule cells were divided into four groups according to the different stimuli: Ad-GFP group, only transfected GPT-adenovirus vector (Adv) in C2C12 myoblasts; Ad-ROCKl group, transfected ROCKl-Adv in C2C12 myoblasts to induce ROCK1 overexpression; Ad-GFPF group, transfected GFP-Adv and given 10 μmol/L fasudil in C2C12 myoblasts; and Ad-ROCKIF group, transfected ROCKl-Adv and given 10 μmol/L fasudil in C2C12 myoblasts. The oxygen consumption rate (OCR) and extracelluar acidification rate (ECAR) of C2C12 myoblasts under different stimulation conditions were evaluated by cell energy metabolism analyzer (Seahorse), so as to determine the effect of ROCK1 overexpression and fasudil stimulation on the respiratory function of C2C12 myoblasts. Mitochondrial fission was measured by MitoTracker® red fluorescent probes. The expressions of ROCK1, mitochondrial related protein 1 (Drpl) and phosphorylated p-Drpl, E3 ubiquitin ligase muscle RING finger-1 protein (MuRFl) and muscle atrophy F-box (MAFbx, Atrogin 1) was measured by Western blotting analysis. Results Seahorse analysis showed that the OCR, ECAR, basal respiration, maximal respiration and respiration required for coupling ATP of C2C12 myoblasts in the Ad ROCK1 group were significantly increased compared with those in the Ad-GFP group (P<0.01); Meanwhile, MitoTracker® staining showed that the mitochondrial fission was increased and the mitochondrial size frequency distribution shifted left in the Ad-ROCK1 group. After exposed to fasudil. the OCR and EACR of C2C12 myoblasts in the Ad-ROCKIF group were significantly decreased versus the Ad-ROCK1 group, and the basal respiration and maximal respiration were significantly increased (P<0.05). Western blotting analysis showed that p-Drpl/Drpl ratio, and the expressions of ROCK1, MuRFl and Atroginl in Ad-ROCKIF group were significantly reduced compared with Ad-ROCKl group (P<0.05). Conclusion Fasudil, an inhibitor of ROCK1, can block the abnormal cell respiration of C2C12 myoblasts caused by overexpressed ROCK 1 in vitro, and can reduce the activity of mitochondrial kinetic protein and the expression of muscle atrophy-related proteins.

The characteristics of F-waves in patients with Kennedy's disease / 中华神经科杂志

Objective To investigate the characteristics of F-waves in patients with Kennedy's disease.Methods Thirty two patients with Kennedy's disease and 30 male healthy volunteers,who visited the Department of Neurology,Peking Union Medical College Hospital between August 2013 and July 2014,were recruited consecutively for this study.Motor nerve conduction study and F-wave examination were performed on the median,ulnar,tibial and peroneal nerves of all participants.A series of 100 electrical stimuli were employed to obtain F-waves.The F-wave parameters in all tested nerves were compared between patients with Kennedy's disease and normal controls including F-wave minimum latency,F-wave persistence,mean and maximum F-wave amplitude,the frequency of giant F-waves.Results The mean Fwave amplitude (median nerve:patients with Kennedy's disease 375.0 (298.3) μV,healthy volunteers 297.0(145.0) μV,Z =-3.378,P ＜0.01;ulnar nerve:patients with Kennedy's disease 397.5(295.0) μV,healthy volunteers 293.0 (101.8) μV,Z =-3.968,P ＜ 0.01;tibial nerve:patients with Kennedy's disease 374.5 (227.3) μV,healthy volunteers 294.0 (160.5) μV,Z =-3.144,P =0.002;peroneal nerve:patients with Kennedy's disease 346.5 (292.8) μV,healthy volunteers 146.5 (69.3) μV,Z =-6.864,P ＜ 0.01),maximum F-wave amplitudes (median nerve:patients with Kennedy's disease 1 291.0 (952.0) μV,healthy volunteers 846.5 (523.0) μV,Z =-4.823,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 1 663.5 (1 374.0) μV,healthy volunteers 760.5 (341.8) μV,Z =-6.813,P ＜ 0.01;tibial nerve:patients with Kennedy's disease (1 054.1 ± 451.6) μV,healthy volunteers (652.5-± 172.5) μV,t =5.380,P ＜ 0.01;peroneal nerve:patients with Kennedy's disease (840.4 ± 494.1) μV,healthy volunteers (370.2 ± 202.0) μV,t =6.475,P ＜ 0.01),frequency of giant F-waves (median nerve:patients with Kennedy's disease 0.0％ (7.2％),healthy volunteers 0.0％ (0.0％),Z =-5.149,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 3.1％ (10.5％),healthy volunteers 0.0％ (0.0％),Z =-7.026,P ＜0.01;tibial nerve:patients with Kennedy's disease 0.0％ (3.3％),healthy volunteers 0.0％ (0.0％),Z =-4.651,P ＜0.01;peroneal nerve:patients with Kennedy's disease 3.3％ (28.2％),healthy volunteers 0.0％ (0.0％),Z =-5.532,P ＜0.01),and frequencies of patients with giant F-waves (median nerve:patients with Kennedy's disease 78.1％ (25/32),healthy volunteers 10.0％ (3/30),x2 =29.016,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 87.5％ (28/32),healthy volunteers 10.0％ (3/30),x2 =37.200,P ＜ 0.01;tibial nerve:patients with Kennedy's disease 62.5％ (20/32),healthy volunteers 6.7％ (2/30),x2 =21.085,P ＜ 0.01;peroneal nerve:patients with Kennedy's disease 68.8 ％ (22/32),healthy volunteers 10.0％ (3/30),x2 =22.209,P ＜ 0.01) in all nerves examined were significantly higher in patients with Kennedy's disease than in the normal controls.The F-wave persistence in all nerves examined was significantly lower than in the normal controls (median nerve:patients with Kennedy's disease 52.5％ (36.3％),healthy volunteers 98.0％ (7.0％),Z =9.010,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 71.0％ (28.3％),healthy volunteers 100.0％ (1.0％),Z =9.455,P ＜ 0.01;tibial nerve:patients with Kennedy's disease 100.0％ (2.0％),healthy volunteers 100.0％ (0.0％),Z =4.255,P ＜ 0.01;peroneal nerve:patients with Kennedy's disease 33.1％ ± 23.9％,healthy volunteers 46.9％ ± 27.2％,t =-2.848,P =0.007).Giant F-waves were detected in multiple nerves and often appeared symmetrically on the same nerves between the left and right sides in patients with Kennedy's disease.No significant correlations were found between the pooled frequency of giant F-waves and disease duration in patients with Kennedy's disease(r =0.162,P =0.418).Conclusions The results showed increased F-wave amplitudes,increased number of giant F-waves,especially giant F-waves detected in multiple nerves or appearing symmetrically combined with low persistence,consistent with the pathologic features of chronic and unselected loss of anterior horn cells in patients with Kennedy's disease.

Application of basic fibroblast growth factor gene-transfected bone marrow mesenchymal stem cells in denervated muscle atrophy / 中国组织工程研究

BACKGROUND:How to avoid denervated muscular atrophy is a key factor to improve the therapeutic efficacy on peripheral nerve injuries. OBJECTIVE:To study the effect of basic fibroblast growth factor (bFGF) gene-transfected bone marrow mesenchymal stem cels against denervated muscle atrophy. METHODS: bFGF genes were transfected into rat bone marrow mesenchymal stem cels using viral transfection method, and then MTT, immunohistochemical staining, hematoxylin-eosin staining, RT-PCR, western blot, and ELISA methods were used to detect the transfection efficiency and product expression. Thirty-two Sprague-Dawley rats were selected to make animal models of sciatic nerve injury, and subjected to multi-point intramuscular injection of bFGF-transfected bone marrow mesenchymal stem cels (experimental group) or cel culture fluid (control group). At 2, 4, 6, 8 weeks after transfection, the gastrocnemius muscle tissues were harvested to detect action potential, residual wet weight, and cross-sectional area of muscle fibers. RESULTS AND CONCLUSION:The bFGF gene was successfuly transfected into bone marrow mesenchymal stem cels using the viral transfection method. The residual wet weight, cross-sectional area and residual action potential of the gastrocnemius muscle were significantly better in the experimental group than the control group (P < 0.05). These findings indicate that bFGF gene-transfected bone marrow mesenchymal stem cels transplanted into the denervated muscle can retard the development of muscle atrophy. Cite this article:Yu N, Wang YS, Qi CP.Application of basic fibroblast growth factor gene-transfected bone marrow mesenchymal stem cels in denervated muscle atrophy. Zhongguo Zuzhi Gongcheng Yanjiu. 2016;20(1):89-94.

MicroRNA and muscle atrophy: Recent progress / 第二军医大学学报

MicroRNA (miRNA) is involved in the regulation of many genes at the post-transcriptional level and plays an important role in many physiological and pathological processes. More and more evidence suggests that muscle atrophy diseases are related to the regulation of miRNA , which indicting that miRNA may have a great potential to become biomarkers and drug targets for the treatment and diagnosis of the disease. This paper outlined the progress of miRNA in muscle atrophy, hoping to provide a theoretical basis for the prevention and treatment of muscle diseases.

Human umbilical cord mesenchymal stem cells transplantation delays denervated muscle atrophy in rats / 中国组织工程研究

BACKGROUND:Slow growth of peripheral nerve, muscle denervation atrophy and fossilization of motor end plate fol owing sciatic nerve injury cause irreversible limb function disorders. Umbilical cord mesenchymal stem cells have been widely used in multi-disciplinary research, but studies concerning umbilical cord mesenchymal stem cells delaying denervated muscle atrophy in rats fol owing peripheral nerve injury are rarely reported. OBJECTIVE:To observe the value of human umbilical cord mesenchymal stem cells transplantation to delay denervated muscle atrophy of rats after sciatic nerve injury. METHODS:Umbilical cord blood was col ected from healthy parturient woman after ful-term delivery. In the experimental group, the rat’s Sunderland IV degree sciatic nerve injury model was established by 5 mm denervation, epineurial repair, and 5 mm smal gap transplantation of umbilical cord mesenchymal stem cells. In the control group, after modeling, the same volume of normal saline was injected into the smal gap. The main outcome measures included the sciatic nerve function index, the wet weight of triceps surae,sciatic nerve latency, action potential conduction velocity and amplitude,and skeletal muscle fiber cross section area maintenance rate. RESULTS AND CONCLUSION:After 4, 8 and 12 weeks of modeling, the sciatic nerve function index values, the wet weight of triceps surae and skeletal muscle fiber cross section area maintenance rates in the experimental group were significantly higher than those in the control group (P<0.05). After 12 weeks of modeling, electromyography results showed sciatic nerve latency was significantly lower, but action potential conduction velocity and amplitude were dramatical y higher in the experimental group than the control group (P<0.05, P<0.001). Human umbilical cord mesenchymal stem cells transplantation in denervated muscle atrophy rats after sciatic nerve promotes nerve growth, delays denervated muscle atrophy, maintains the denervatied neuromusle’s morphology and function.

Hirayama disease simple presenting proximal upper extremity muscular atrophy / 中华骨科杂志

Objective To investigate the clinical features and magnetic resonance imaging (MRI)findings of patients with Hirayama disease simply presenting proximal upper extremity muscular atrophy.Methods Three patients with Hirayama disease simply presenting proximal upper extremity muscular atrophy received cervical spine MRI on neutral and flexion position. The relationship between MRI findings and their clinical symptoms were analyzed. The outcomes were compared with those of 43 patients who were diagnosed as Hirayama disease with muscular atrophy at the hand and forearm. Results 1) Clinical features:three patients were young men. The disease was characterized by unilateral weakness and atrophy of the proximal upper limbs, such as pectoralis major muscle, deltoid muscle, and biceps brachii muscle. Electromyogram (EMG) showed bilateral upper extremities neurogenic damage. 2) Cervical spine MRI findings:cervical spine kyphosis without spinal cord compression was found on neutral position. On flexion position,anterior shifting of C3-C5 cervical cord and the posterior wall of dural sac were found; C4-C5 cervical cord was compressed by vertebral body or intervertebral disc or dural sac. Engorged posterior internal vertebral venous plexus were observed in epidural space. In the 43 patients who were diagnosed Hirayama disease with muscular atrophy at the hand and forearm, similar MRI findings were found, while cervical cords compression were at C6-C7 level. Conclusion Hirayama disease could present as proximal upper extremity muscular atrophy and weakness, such as pectoralis major muscle, deltoid muscle, and biceps brachii muscle.Neglecting of this will result in diagnostic errors or missed diagnosis. Flexion position MRI is an important base of early diagnosis of Hirayama disease.