Search results for " Muscle"
showing 10 items of 1495 documents
Results of an Observational Cohort Study of Hyperuricemia as a Predictor of Poor Physical Performance in the Elderly
2017
Objective: Hyperuricemia is frequent in older people and associated with several medical conditions. The relationship between hyperuricemia and physical performance is limited. We aimed to investigate the association between hyperuricemia and physical performance over a 4.4-year followup in the elderly. Methods: A total of 1,904 community-dwelling older participants were followed for a mean of 4.4 years. Hyperuricemia at baseline was defined using serum uric acid concentrations ≥6 and ≥7 mg/dl for women and men, respectively. Objective physical performance tests measured included the Short Physical Performance Battery (SPPB), 4-meter gait speed, chair-stands time, leg extension and flexion,…
Inhibitory effects of indicaxanthin on mouse ileal contractility: analysis of the mechanism of action.
2011
Recently, we have showed that indicaxanthin, the yellow betalain pigment abundant in the fruit of Opuntia ficus indica, has remarkable spasmolytic effects on the intestinal contractility in vitro. Thus, the purpose of the present study was to investigate the mechanism of action underlying the observed response. We used organ bath technique to record the mechanical activity of the mouse ileum longitudinal muscle and ELISA to measure the levels of cAMP. Indicaxanthin induced inhibitory effects on spontaneous mechanical activity, which were unaffected by indomethacin, a non-selective inhibitor of cycloxygenase; 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a selective inhibitor of nitric oxide-…
Carnitine transport into muscular cells. inhibition of transport and cell growth by mildronate
2000
Carnitine is involved in the transfer of fatty acids across mitochondrial membranes. Carnitine is found in dairy and meat products, but is also biosynthesized from lysine and methionine via a process that, in rat, takes place essentially in the liver. After intestinal absorption or hepatic biosynthesis, carnitine is transferred to organs whose metabolism is dependent on fatty acid oxidation, such as heart and skeletal muscle. In skeletal muscle, carnitine concentration was found to be 50 times higher than in the plasma, implicating an active transport system for carnitine. In this study, we characterized this transport in isolated rat myotubes, established mouse C2C12 myoblastic cells, and …
Effects of Lycopene, Indole-3-Carbinol, and Luteolin on Nitric Oxide Production and iNOS Expression are Organ-Specific in Rats
2010
Effects of Lycopene, Indole-3-Carbinol, and Luteolin on Nitric Oxide Production and iNOS Expression are Organ-Specific in RatsNatural compounds are known to modify NO content in tissues; however, the biological activity of polyphenol-rich food often does not correspond to the effects of individual polyphenols on NO synthase activity. The aim of this study was to see how natural compounds luteolin, indole-3-carbinol, and lycopene modify NO production in rat tissues and change the expression of the iNOS gene and protein. Indole-3-carbinol produced multiple effects on the NO level; it significantly decreased NO concentration in blood, lungs, and skeletal muscles and increased it in the liver. …
Comparison of Electromyographic Activity During Hip Extension Exercises Under Gravitational or Inertial Loading Conditions.
2021
Background: Hamstring injury prevention programs include strengthening, especially eccentric exercises using both gravitational and inertial loading. Inertial exercises are characterized by eccentric contractions of high intensity and velocity. This study aimed to analyze the muscular activation of the biceps femoris (BF), semitendinosus (ST), gluteus maximus (GM), and gracilis (GC) muscles during hip extension (HE) exercises performed under both gravitational and inertial loading conditions. Hypothesis: Inertial training would generate a greater activation of HE muscles than gravitational training. Study Design: Cross-sectional study. Level of Evidence: Level 4. Methods: Fifteen resistance…
Sex Differences in the Velocity of Muscle Contraction of the Hamstring and Quadriceps Among Recreationally Active Young Adults
2019
Martin-San Agustin, R, Medina-Mirapeix, F, Alakhdar, Y, and Benitez-Martinez, JC. Sex differences in the velocity of muscle contraction of the hamstring and quadriceps among recreationally active young adults. J Strength Cond Res 33(5): 1252-1257, 2019-This study determines sex differences in the velocity of contraction (VC) of 5 isolated muscles (biceps femoris, semitendinosus, rectus femoris, vastus medialis, and vastus lateralis) and in the relationships between them. Thirty-six female and 34 male recreationally active young adults participated in the study. The VC was measured by tensiomyography using normalized response velocity (Vrn) to perform comparisons. Sex comparisons were adjust…
Muscarinic receptors, leukotriene B4 production and neutrophilic inflammation in COPD patients.
2005
Background: Acetylcholine (ACh) plays an important role in smooth muscle contraction and in the development of airway narrowing; preliminary evidences led us to hypothesize that ACh might also play a role in the development of airways inflammation in chronic obstructive pulmonary disease (COPD). Methods: We evaluated the concentrations of leukotriene B4 (LTB4) in induced sputum, and the expression of Ach M1, M2, and M3 receptors in sputum cells (SC) obtained from 16 patients with COPD, 11 smokers, and 14 control subjects. The SC were also treated with ACh and the production of LTB4 assessed in the presence or absence of a muscarinic antagonist (oxitropium). In blood monocytes, we evaluate…
Gracilis free muscle transfer for morpho-functional reconstruction of the lower lip.
2007
Background. Large full-thickness defects of the lower lip need free tissue transfer. The free forearm flap is the more widespread technique for free flap lower lip reconstruction, but it results in a static lip. The authors describe a technique of morphodynamic sensate reconstruction of the lower lip with a free gracilis flap and a musculomucosal flap. Methods. Three patients underwent reconstruction with an innervated free muscular gracilis flap, an innervated musculo-mucosal flap for the vermillion (2 cases), and a full-thickness skin graft. Results. No significant complications were observed. Static function and vermillion sensitivity were immediately restored. The skin color match was e…
Signal characteristics of EMG during fatigue
1977
Electromyographic (EMG) activity of m. rectus femoris muscle was registered from young male and female subjects during maintained isometric knee extension at 60% of maximal voluntary contraction. The following EMG parameters were analyzed for the entire fatigue time: integrated EMG (IEMG), averaged motor unit potential (AMUP) and power spectral density function (PSDF). The results indicated a slight but continuous rise of IEMG during the fatigue period. AMUP showed sensitivity to fatigue with increase in amplitude, rise time, and number of spikes counted. PSDF was also easily affected by fatigue so that the total power density curve was shifted towards lower frequencies with a high frequenc…
Diabetic 3rd nerve palsy: evidence for a mesencephalic lesion.
1990
Eleven consecutive adult chronic diabetic patients presented with an isolated 3rd nerve palsy (8 with pupillary sparing) of which 10 had abnormal ipsilateral or bilateral masseter reflexes (MassR). Three patients had an MRI lesion in the ipsilateral oculomotor fasciculus and 3 had subsequent mild brainstem signs. An additional 13 patients with Weber's syndrome had similar ipsilateral or bilateral MassR abnormalities, while 7 patients with 3rd nerve palsies on a known extra-axial basis had none. The findings suggest that an isolated diabetic 3rd nerve palsy, with or without pupillary sparing, is much more likely on the basis of a focal mesencephalic infarct than a peripheral nerve lesion.