scholarly journals Possible involvement of adenosine triphosphate in the mechanisms of protein sensibilization effect on the functional properties of the diaphragm and skeletal muscles

2012 ◽  
Vol 93 (1) ◽  
pp. 113-116
Author(s):  
A Yu Teplov ◽  
A M Farkhutdinov ◽  
S N Grishin ◽  
M M Minnebaev ◽  
V I Torshin
Keyword(s):  
Adenosine Triphosphate ◽  
Functional Properties ◽  
Skeletal Muscles ◽  
Contractile Function ◽  
Muscular Contraction ◽  
Postsynaptic Membrane ◽  
Experimental Models ◽  
Force Vector ◽  
Leg Muscles ◽  
Before And After

Aim. To study the effect of adenosine triphosphate on the contractile function and non-quantum secretion of acetylcholine at the endplate zone (H-effect) of isolated mouse muscles on the background of protein sensibilization. Methods. The experiments were performed on white mice. Sensibilization was carried out by ovalbumin with an aluminum hydroxide gel. Mechanomyography studies were performed on isolated preparations of the diaphragm and of two leg muscles in isometric conditions. The contractions were recorded by a photoelectric converter. In order to study the condition of the postsynaptic membrane of the muscle fibers measured was the non-quantum secretion of acetylcholine. Compared were the parameters of muscle contraction before and after 5 min of perfusion with a solution of adenosine triphosphate. Results. In the diaphragm and in the soleus muscle the dynamics of the force vector of the muscular contraction correlated with the changes in the H-effect in all the studied experimental models. However, the extent of these changes in the sensibilized animals is less pronounced. Conclusion. It is possible that adenosine triphosphate affects the functional properties of both muscle during protein sensibilization; the change in the contraction force of the long extensor digitorum muscle during sensibilization is not related to the mechanisms of muscle excitation, mediated by adenosine triphosphate.

Plasticity of the Muscles in the Protein Sensitization. Involvement of Cholinergic asnd Purinergic Mechanisms

10.12737/3300 ◽  
2014 ◽  
Vol 21 (1) ◽  
pp. 6-12
Author(s):  
Теплов ◽  
O. Teplov ◽  
Миннебаев ◽  
M. Minnebaev ◽  
Фархутдинов ◽  
...  
Keyword(s):  
Adenosine Triphosphate ◽  
Extensor Digitorum Longus ◽  
Striated Muscle ◽  
Contractile Function ◽  
Experimental Models ◽  
Extensor Digitorum ◽  
Chronic Obstructive ◽  
Respiratory Muscle Fatigue ◽  
Development Of Resistance ◽  
Protein Sensitization

The authors investigated the involvement of the adenosine triphosphate (ATF) in the mechanisms of plasticity in the striated muscle in condition of protein sensitization. Contractile function and non-quantum secretion of the acetylcholine in the endplate zone were studied in isolated skeletal muscles of mouse legs (musculus soleus and musculus extensor digitorum longus) and strips musculus diaphragm. The authors studied the soleus and diaphragm dynamics of the force vector of muscle contraction after effects of exogenous adenosine triphosphate correlated with changes non-quantum secretion of acetylcholine in all the experimental models. However, the extent of these changes in sensitized animals is less pronounced than in the controls. It is suggested that adenosine is a party change mechanisms and functional properties soleus and diaphragm at the protein sensitization. The basis of the development of resistance, stability to long as the external stress, and at the initial stages of the experimental allergic these muscles are dependent adenosine mechanisms regulating their sensitivity to acetylcholine. These processes provide a reduction in respiratory muscle fatigue in hypoxia that occurs in asthma, chronic obstructive pulmonary disease and broncho-spastic syndrome, as well in increase their performance during prolonged physical activity. The reasons for changes in the force reduction extensor digitorum longus at a protein sensitization doesn’t associated with the mechanisms of muscle excitation mediated by adenosine triphosphate.

The influence of osteopathic correction on the viscoelastic characteristics of the lower leg muscles

2019 ◽  
pp. 93-98
Author(s):  
E. M. Timanin ◽  
N. S. Sydneva ◽  
A. A. Zakharova
Keyword(s):  
Viscoelastic Properties ◽  
Gastrocnemius Muscle ◽  
Soft Tissues ◽  
Subjective Assessment ◽  
Lymphatic Drainage ◽  
Intercellular Substance ◽  
Leg Muscles ◽  
Before And After ◽  
Viscoelastic Characteristics ◽  
Instrumental Methods

Introduction. To date there is a lack of studies dedicated to the objectification of the palpation data obtained by a specialist during the osteopathic examination. The issue of the evidence of the results of osteopathic correction still remains important. Search for instrumental methods allowing to register and to measure various palpation phenomena and manifestations of somatic dysfunctions is very relevant for the development of osteopathy as a science. It is also very important to find objective characteristics of these methods.Goal of research — to study viscoelastic characteristics of the soft tissues of the lower legs by palpation and instrumental methods before and after osteopathic correction.Materials and methods. 22 volunteers (12 women and 10 men) aged 18–23 years without complaints of the musculoskeletal system were examined. Osteopathic diagnostics and measurement of the viscoelastic properties of muscles were carried out by the method of vibration viscoelastometry before and after osteopathic correction.Results. Correlation analysis by Spearman showed that the subjective assessment of an osteopath positively correlated with both elasticity (r=0,43, p<0,05) and viscosity of soft issues (r=0,29, p<0,05). For the gastrocnemius muscle, this pattern was even more pronounced — for elasticity r=0,51, p<0,05, for viscosity =0,34, p<0,05. After osteopathic correction no changes in the elasticity of the soft tissues were observed. The viscosity of the tissues reduced, but in the projection of the gastrocnemius muscle, these changes were not statistically significant (p=0,12), whereas in the projection of the soleus muscle statistically significant changes (p=0,034) were observed.Conclusion. Changes in the viscoelastic properties of tissues demonstrated that the effects of osteopathic correction with the use of myofascial mobilization techniques, articulation mobilization techniques, and lymphatic drainage techniques were not obvious. The elasticity of soft tissues of the lower legs did not change, while the viscosity decreased, especially in the projection of the soleus muscles. This effect of the osteopathic correction can be associated with the effect of thixotropy — the transformation of gel-like intercellular substance into sol. Thus, the research showed that vibration viscoelastometry can be used for the objectifi cation of the condition of soft tissues and of the effects of osteopathic correction.

Finite Deformation Stiffness of Sliding Elastomeric Bearings

2011 ◽  
Vol 374-377 ◽  
pp. 1858-1862
Author(s):  
Jian Chun Xiao ◽  
Peng Liu ◽  
Ke Jian Ma
Keyword(s):  
Parametric Analysis ◽  
Steel Plates ◽  
Structural Behavior ◽  
Analysis Method ◽  
Force Vector ◽  
Elastomeric Bearings ◽  
Before And After ◽  
Bearing Stiffness ◽  
Vector Formula

Anchor bolts are set in some elastomeric bearings of large-span column-supported spatial steel roofs. Besides helping the bearing in-site assembly, the bolts play the roles of sliding position limitation and vertical anchorage. To analyze the effect of bearings on nonlinear structural behavior, the bearing stiffness change is studied just before and after the elastomer pad is in contact with the bolts. For the bearing that the pad is glued with the top/bottom steel plates, three kinds of relation of pad and bolts are discussed and an approximate horizontal stiffness formula is obtained with parametric analysis method. Based on the analysis results a stiffness expression for sliding elastomeric bearings is deduced. To solve the computational problem caused by the bearing stiffness changes, an improved imbalance force vector formula is proposed. Case study shows that the bolts have influence upon the computed results more significantly.

scholarly journals EVALUATION OF THREE SURFACE FRICTION TECHNIQUES FOR THE REMOVAL OF ORGANIC MATTER

2015 ◽  
Vol 24 (4) ◽  
pp. 1061-1070 ◽  
Author(s):  
Marcelo Alessandro Rigotti ◽  
Adriano Menis Ferreira ◽  
Mara Corrêa Lelles Nogueira ◽  
Margarete Teresa Gottardo de Almeida ◽  
Odanir Garcia Guerra ◽  
...  
Keyword(s):  
Organic Matter ◽  
Adenosine Triphosphate ◽  
Organic Material ◽  
Surface Friction ◽  
Disinfection Process ◽  
Significant Difference ◽  
Before And After ◽  
Quantitative Descriptive ◽  
The One ◽  
Cleaning And Disinfection

ABSTRACT The objective of this study was to assess the effectiveness of three surface friction techniques for the removal of organic material. A quantitative, descriptive and exploratory study was developed to evaluate the presence or not of organic material before and after the cleaning and disinfection process of surfaces of bedside tables of patients hospitalized at an Intensive Care Unit. Three friction techniques were executed in the one-way, two-way and centrifugal sense, individually, three times on each table, during alternate weeks. For each patient unit and friction technique, a single table and three sides of cloth were used, moistened with 70% (w/v) alcohol. The organic matter was detected through the presence of adenosine triphosphate by bioluminescence, using 3M(tm) Clean-Trace(tm) ATP Systems. For each technique, 13 samples were collected before and 13 after the cleaning/disinfection process, totaling 78 samples of adenosine triphosphate by bioluminescence. No statistically significant difference was found among the removal techniques of organic matter. This study demonstrated that none of the three surface friction methods was better than the other to remove organic matter. Nevertheless, further research is needed in which other cleaning/disinfection indicators and surfaces are considered.

Short-Term Potentiation of Miniature Excitatory Synaptic Currents Causes Excitation of Supraoptic Neurons

2000 ◽  
Vol 83 (5) ◽  
pp. 2542-2553 ◽  
Author(s):  
Samuel B. Kombian ◽  
Michiru Hirasawa ◽  
Didier Mouginot ◽  
Xihua Chen ◽  
Quentin J. Pittman
Keyword(s):  
Nmda Receptors ◽  
Postsynaptic Membrane ◽  
High Frequency Stimulation ◽  
Excitatory Synapses ◽  
Short Term ◽  
Cell Excitability ◽  
Term Potentiation ◽  
Before And After ◽  
Frequency Stimulation ◽  
Supraoptic Neurons

Magnocellular neurons (MCNs) of the hypothalamic supraoptic nucleus (SON) secrete vasopressin and oxytocin. With the use of whole-cell and nystatin-perforated patch recordings of MCNs in current- and voltage-clamp modes, we show that high-frequency stimulation (HFS, 10–200 Hz) of excitatory afferents induces increases in the frequency and amplitude of 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(f)quinoxaline-7-sulfonamide (NBQX)-sensitive miniature excitatory postsynaptic currents (mEPSCs) lasting up to 20 min. This synaptic enhancement, referred to as short-term potentiation (STP), could be induced repeatedly; required tetrodotoxin (TTX)-dependent action potentials to initiate, but not to maintain; and was independent of postsynaptic membrane potential, N-methyl-d-aspartate (NMDA) receptors, or retrograde neurohypophyseal neuropeptide release. STP was not accompanied by changes in the conductance of the MCNs or in the responsiveness of the postsynaptic non-NMDA receptors, as revealed by brief application of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate. mEPSCs showed similar rise times before and after HFS and analysis of amplitude distributions of mEPSCs revealed one or more peaks pre-HFS and the appearance of additional peaks post-HFS, which were equidistant from the first peak. STP of mEPSCs was not associated with enhanced evoked responses, but was associated with an NBQX-sensitive increase in spontaneous activity of MCNs. Thus we have identified a particularly long-lasting potentiation of excitatory synapses in the SON, which has a presynaptic locus, is dissociated from changes in evoked release, and which regulates postsynaptic cell excitability.

scholarly journals Effectiveness of Surface Cleaning and Disinfection in a Brazilian Healthcare Facility

2018 ◽  
Vol 12 (1) ◽  
pp. 36-44 ◽  
Author(s):  
Aires G. Santos-Junior ◽  
Adriano M. Ferreira ◽  
Oleci P. Frota ◽  
Marcelo A. Rigotti ◽  
Larissa da S. Barcelos ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Adenosine Triphosphate ◽  
Healthcare Facility ◽  
Surface Cleaning ◽  
Point Of View ◽  
Colony Count ◽  
Before And After ◽  
Bioluminescence Assay ◽  
Cleaning And Disinfection ◽  
Hospital Cleaning

Background: Failures in the processes of cleaning and disinfecting health service surfaces may result in the spread and transfer of pathogens that are often associated with healthcare-related infections and outbreaks. Aims: To assess the effectiveness of environmental surface cleaning and disinfection in a hospital clinic. Method: The study was conducted in a nursing ward with 45 beds. A total of 80 samples from five high-touch surfaces were evaluated before and after cleaning and disinfection, using the following methods: visual inspection, adenosine triphosphate bioluminescence assay, aerobic colony count, Staphylococcus aureus colony count, and evaluation of resistance to methicillin. The data analysis used nonparametric comparative and correlative tests to observe any differences in the pre- and post- cleaning and disinfection results for the surfaces assessed. Results: Effective cleaning and disinfection had a significant effect on only two surfaces when measured for the presence of adenosine triphosphate, the inner bathroom door handle (p=0.007) and the toilet bowl (p=0.01). When evaluated for Staphylococcus aureus colony count, the toilet flush handle also demonstrated a significant effect (p=0.04). Conclusion: The effectiveness of cleaning and disinfection of the surfaces tested was not satisfactory. An educational intervention is recommended for the cleaning and disinfection staff and the nursing team at the healthcare facility. Relevance to Clinical Practice: The data in the study revealed that daily hospital cleaning and disinfection in the sampled sites are not sufficient in medical and surgical wards. Hospital cleanliness must be reevaluated from the point of view of materials, such as an adequate supply of clean cloths, in addition to establishing more precise cleanliness protocols and accurate monitoring systems.

Barbiturates depress vagal motor pathway to ferret trachea at ganglia

1982 ◽  
Vol 53 (1) ◽  
pp. 253-257 ◽  
Author(s):  
B. E. Skoogh ◽  
M. J. Holtzman ◽  
J. R. Sheller ◽  
J. A. Nadel
Keyword(s):  
Neuromuscular Junction ◽  
Vagus Nerve ◽  
Muscle Tension ◽  
Postsynaptic Membrane ◽  
Nerve Fibers ◽  
Motor Pathway ◽  
Parasympathetic Ganglia ◽  
Before And After ◽  
Nerve Muscle

To determine which site in the vagal motor pathway to airway smooth muscle is most sensitive to depression by barbiturates, we recorded isometric muscle tension in vitro and stimulated the vagal motor pathway at four different sites before and after exposure to barbiturates. In isolated tracheal rings from ferrets, we stimulated muscarinic receptors in the neuromuscular junction by exogenous acetylcholine, postganglionic nerve fibers by electrical fluid stimulation, and the postsynaptic membrane in ganglia by 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP). We also developed a tracheal nerve-muscle preparation to stimulate preganglionic fibers in the vagus nerve electrically. Activation of ganglia by DMPP or by vagus nerve stimulation was depressed by barbiturates at 10-fold lower concentrations than those depressing the activation of postganglionic nerves or the neuromuscular junction. These findings suggest that the postsynaptic membrane in parasympathetic ganglia is the site in the vagal motor pathway most sensitive to depression by barbiturates.

Alpha-adrenergic-mediated reflex responses to induced muscular contraction are changed with age in dogs

1993 ◽  
Vol 265 (6) ◽  
pp. H1899-H1908 ◽  
Author(s):  
G. C. Haidet
Keyword(s):  
Blood Flow ◽  
Regional Blood Flow ◽  
Muscular Contraction ◽  
Related Difference ◽  
Abdominal Organs ◽  
Age Related ◽  
Before And After ◽  
Alpha Blockade ◽  
Anesthetized Dogs ◽  
Age Related Changes

Aging significantly affects reflex cardiovascular (CV) responses to induced muscular contraction in anesthetized dogs. To further investigate whether age-related changes in alpha-adrenergic-mediated responses to muscular contraction contribute to these previously reported age-related changes in CV responses associated with advanced age, hemodynamic and regional blood flow (BF) responses at baseline and during hindlimb contraction (HLC) were evaluated both before and after alpha-blockade (alpha-AB) in older (8-14 yr old) and in younger (2-3 yr old) beagles during alpha-chloralose anesthesia. alpha-AB with phentolamine resulted in significant (P < 0.05) reductions in mean arterial pressure before and during HLC, regardless of age. However, age-related differences in the systemic vascular resistance, cardiac output, and stroke volume responses to HLC, observed before alpha-AB, were eliminated after phentolamine as the result of an age-related difference in each of these responses to alpha-AB. Baseline BF (microspheres) was unchanged after alpha-AB in seven of eight abdominal organs, regardless of age. However, reductions in BF during HLC were attenuated in seven of eight abdominal organs in the younger dogs after alpha-AB, but in none of these organs in the older dogs, indicative of diminished alpha-mediated vasoconstriction in these organs in the older dogs during HLC. Furthermore, the age-related difference in the combined BF reduction to all eight abdominal organs before alpha-AB was eliminated after alpha-AB. Finally, BF increases to two of four contracting muscles, as well as the combined increase in blood flow to all four contracting muscles, were attenuated after alpha-AB, regardless of age. These results demonstrate that alpha-blockade eliminates many of the age-related differences in CV responses to HLC observed before alpha-AB and suggest that alpha-adrenergic-mediated responses to HLC change with age in beagles.

scholarly journals Tenogenic Contribution to Skeletal Muscle Regeneration: The Secretome of Scleraxis Overexpressing Mesenchymal Stem Cells Enhances Myogenic Differentiation In Vitro

2020 ◽  
Vol 21 (6) ◽  
pp. 1965
Author(s):  
Maximilian Strenzke ◽  
Paolo Alberton ◽  
Attila Aszodi ◽  
Denitsa Docheva ◽  
Elisabeth Haas ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Regeneration ◽  
Skeletal Muscles ◽  
Myogenic Differentiation ◽  
Muscular Contraction ◽  
Myoblast Fusion ◽  
Skeletal Muscle Regeneration ◽  
Potential Candidate ◽  
Musculoskeletal Tissue

Integrity of the musculoskeletal system is essential for the transfer of muscular contraction force to the associated bones. Tendons and skeletal muscles intertwine, but on a cellular level, the myotendinous junctions (MTJs) display a sharp transition zone with a highly specific molecular adaption. The function of MTJs could go beyond a mere structural role and might include homeostasis of this musculoskeletal tissue compound, thus also being involved in skeletal muscle regeneration. Repair processes recapitulate several developmental mechanisms, and as myotendinous interaction does occur already during development, MTJs could likewise contribute to muscle regeneration. Recent studies identified tendon-related, scleraxis-expressing cells that reside in close proximity to the MTJs and the muscle belly. As the muscle-specific function of these scleraxis positive cells is unknown, we compared the influence of two immortalized mesenchymal stem cell (MSC) lines—differing only by the overexpression of scleraxis—on myoblasts morphology, metabolism, migration, fusion, and alignment. Our results revealed a significant increase in myoblast fusion and metabolic activity when exposed to the secretome derived from scleraxis-overexpressing MSCs. However, we found no significant changes in myoblast migration and myofiber alignment. Further analysis of differentially expressed genes between native MSCs and scleraxis-overexpressing MSCs by RNA sequencing unraveled potential candidate genes, i.e., extracellular matrix (ECM) proteins, transmembrane receptors, or proteases that might enhance myoblast fusion. Our results suggest that musculotendinous interaction is essential for the development and healing of skeletal muscles.

Sign in / Sign up

Export Citation Format

Share Document