Muscle contraction

The objective of this research is to study the effect of onset of physical fatigue/stress during isometric and dynamic contractions based on the changes in physiological signal i.e. SEMG. Therefore, the intention of this present investigation is to assess the repeatability of common muscle fatigue measures, including amplitude and spectral measures of EMG and further, to determine the adequacy of different measures in detection of onset of localized muscle fatigue.

122p runthenight07 01-03-2023 8 3   Download

In this study, we isolated a 25-kDa novel snake venom protein, designated ablomin, from the venom of the Japanese Mamushi snake (Agkistrodon blomhoffi). The amino-acid sequence of this protein was determined by peptide sequencing and cDNA cloning. The deduced sequence showed high similarity to helothermine from the Mexican beaded lizard (Heloderma horridum horridum), which blocks voltage-gated calcium and potassium channels, and ryanodine receptors. Ablomin blocked contraction of rat tail arterial smooth muscle elicited by high K+-induced depolarization in the 0.

8p system191 01-06-2013 26 3   Download

The Ca 2+ -induced transition in the troponin complex (Tn) regulates vertebrate striated muscle contraction. Tn was reconstituted with recombinant forms of troponin I (TnI) containing a single intrinsic 5-hydroxytryptophan (5HW). Fluorescence analysis of these mutants of TnI demonstrate that the regions in TnI that respond to Ca 2+ binding to the regulatoryN-domain of TnC are the inhibitoryregion (residues 96–116) and a neighboring region that includes position 121.

8p fptmusic 16-04-2013 39 4   Download

Vertebrate troponin regulates muscle contraction through alternative bind-ing of the C-terminal region of the inhibitory subunit, troponin-I (TnI), to actin or troponin-C (TnC) in a Ca 2+ -dependent manner. To elucidate the molecular mechanisms of this regulation by molluskan troponin, we com-pared the functional properties of the recombinant fragments of Akazara scallop TnI and rabbit fast skeletal TnI.

12p fptmusic 11-04-2013 34 2   Download

The troponin (Tn) complex is formed by TnC, TnI and TnT and is respon-sible for the calcium-dependent inhibition of muscle contraction. TnC and TnI interact in an antiparallel fashion in which the N domain of TnC binds in a calcium-dependent manner to the C domain of TnI, releasing the inhibitory effect of the latter on the actomyosin interaction. While the crys-tal structure of the core cardiac muscle troponin complex has been deter-mined, very little high resolution information is available regarding the skeletal muscle TnI–TnC complex. ...

0p awards 05-04-2013 34 3   Download

This review describes the early beginnings of X-ray diffrac-tion work on muscle structure and the contraction mech-anismin the MRC Unit in the Cavendish Laboratory, Cambridge, and later work in the MRC Molecular Biology Laboratory in Hills Road, Cambridge, where the author worked for many years, and elsewhere. The work has depended heavily on instrumentation development, for which the MRC laboratory had made excellent provision. The search for ever higher X-ray intensity for time-resolved studies led to the development of synchrotron radiation as an exceptionally powerful X-ray source....

13p dell39 03-04-2013 42 4   Download

Parvalbumin (PV), a small cytosolic protein belonging to the family of EF-hand calcium-binding proteins, is highly expressed in mammalian fast-twitch muscle fibers. By acting as a ‘slow-onset’ Ca 2+ buffer, PV does not affect the rapid contraction phase, but significantly contributes to increase the rate of relaxation, as demonstrated in PV–⁄– mice.

13p dell39 27-03-2013 40 2   Download

Entrained oscillations in Ca 2+ underlie many biological pacemaking phe-nomena. In this article, we review a long-range signaling mechanism in smooth muscle that results in global outcomes of local interactions. Our results are derived from studies of the following: (a) slow-wave depolariza-tions that underlie rhythmic contractions of gastric smooth muscle;

8p mobifone23 18-01-2013 51 4   Download

The troponin complex plays an essential role in the thin filament regulation of striated muscle contraction. Of the three subunits of troponin, tropo-nin I (TnI) is the actomyosin ATPase inhibitory subunit and its effect is released upon Ca 2+ binding to troponin C.

12p cosis54 09-12-2012 47 3   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Vibration-induced extra torque during electrically-evoked contractions of the human calf muscles

16p panasonic01 12-12-2011 48 4   Download

Reactive oxygen species (ROS) were shown to mediate aberrant contractility in hypertension, yet the physiological roles of ROS in vascular smooth muscle contraction have remained elusive. This study aimed to examine whether ROS regulate a1-adrenoceptor-activated contraction by altering myosin phosphatase activities. Methods: Using endothelium-denuded rat tail artery (RTA) strips, effects of anti-oxidants on isometric force, ROS production, phosphorylation of the 20-kDa myosin light chain (MLC20), and myosin phosphatase stimulated by a1-adrenoceptor agonist phenylephrine were examined.

10p toshiba23 18-11-2011 50 2   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: Research Skeletal muscle contraction. The thorough definition of the contractile event requires both load acceleration and load mass to be known...

14p toshiba17 28-10-2011 40 3   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: "Role of contractile prostaglandins and Rho-kinase in growth factor-induced airway smooth muscle contraction...

11p toshiba14 22-10-2011 54 3   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: The effects of interleukin-8 on airway smooth muscle contraction in cystic fibrosis...

11p toshiba12 20-10-2011 53 5   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: " Nogo-B regulates migration and contraction of airway smooth muscle cells by decreasing ARPC 2/3 and increasing MYL-9 expression...

9p toshiba11 20-10-2011 58 3   Download

Introduction The muscles of the head consist of the chewing muscles (temporalis, masseter, and digastric) and the facial muscles (zygomaticus, orbicularis oris, etc.). The chewing muscles are thick and volumetric, and they originate and insert on bone. They open and close the lower jaw, with the action taking place at the jaw joint (temporomandibular joint). The facial muscles are thin. They originate either from the skull or from the surface of other muscles, and they generally insert into other facial muscles or into the skin.

14p audi123 31-07-2010 154 22   Download