scholarly journals Efeitos e Aplicações do Campo Eletromagnético de Alta Intensidade (PEMF) em saúde e estética: perspectivas e evidências clínicas

2021 ◽  
Vol 10 (14) ◽  
pp. e06101421724
Author(s):  
Rodrigo Alvaro Lopes Martins ◽  
Michele Matias ◽  
Felícia Cadenas de Paiva Bueno ◽  
Mayara Oguri ◽  
Patricia Sardinha Leonardo ◽  
...  

The increased interest and concern with physical fitness, not only from an athletic point of view, but also from an aesthetic point of view, has driven the search for new methods and technologies capable of helping to gain mass and muscle tone. Recent studies show that 81% percent of respondents reported dissatisfaction with their body image, even with 56% having a normal body mass index. Pulsed electromagnetic field (PEMF) muscle stimulation technology uses alternating magnetic fields based on the law of electromagnetic induction to promote supramaximal muscle contractions. PEMF generates impulses that are independent of brain function, and with such a fast frequency that it does not allow the muscle relaxation phase, characterizing tetanic contractions. Electric currents and electromagnetism have been used in physical therapy and rehabilitation, especially for muscle strengthening. However, the PEMF technology has emerged as a more efficient and comfortable alternative for the patient, with the primary objective of toning and strengthening muscle groups. In this work, we performed a literature review of all scientific articles available and indexed in Pubmed and Web of Science about this technology in the last 20 years and its effects on skeletal muscles. We discuss the scientific evidence available from clinical studies and discuss effects and possible mechanisms of action on muscle contraction.

2021 ◽  
Vol 13 (14) ◽  
pp. 7887
Author(s):  
Verónica Muñoz-Arroyave ◽  
Miguel Pic ◽  
Rafael Luchoro-Parrilla ◽  
Jorge Serna ◽  
Cristòfol Salas-Santandreu ◽  
...  

The aim of this research was to study from a multidimensional point of view (decisional, relational and energetic) the interpersonal relationships established by girls and boys in the traditional sport game of Elbow Tag. Scientific evidence has shown that Traditional Sport Games (TSG) trigger different effects on male and female genders in relation to emotional experiences, decision-making, conflicts and motor relationships. Despite the fact that these dimensions are intertwined, there are hardly any studies that interpret motor behaviors holistically, i.e., taking a multidimensional (360°) view of these dimensions. For this study, a quasi-experimental design was used and a type III design was applied, inspired by the observational methodology N/P/M. A total of 147 university students participated (M = 19.6, SD = 2.3): 47 girls (31.97%) and 100 boys (68.02%). A mixed ‘ad hoc’ registration system was designed with acceptable margins of data quality. Cross-tabulations, classification trees and T-patterns analysis were applied. The results indicated that social interactions between girls and boys in a mixed group were unequal. This difference was mainly due to decision-making (sub-role variable), which has much greater predictive power than the energetic variables (MV and steps).


2007 ◽  
Vol 103 (2) ◽  
pp. 511-517 ◽  
Author(s):  
Patricia A. Gwirtz ◽  
Jerry Dickey ◽  
David Vick ◽  
Maurice A. Williams ◽  
Brian Foresman

Studies tested the hypothesis that myocardial ischemia induces increased paraspinal muscular tone localized to the T2–T5 region that can be detected by palpatory means. This is consistent with theories of manual medicine suggesting that disturbances in visceral organ physiology can cause increases in skeletal muscle tone in specific muscle groups. Clinical studies in manual and traditional medicine suggest this phenomenon occurs during episodes of myocardial ischemia and may have diagnostic potential. However, there is little direct evidence of a cardiac-somatic mechanism to explain these findings. Chronically instrumented dogs [12 neurally intact and 3 following selective left ventricular (LV) sympathectomy] were examined before, during, and after myocardial ischemia. Circumflex blood flow (CBF), left ventricular contractile function, electromyographic (EMG) analysis, and blinded manual palpatory assessments (MPA) of tissue over the transverse spinal processes at segments T2–T5 and T11–T12 (control) were performed. Myocardial ischemia was associated with a decrease in myocardial contractile function and an increase in heart rate. MPA revealed increases in muscle tension and texture/firmness during ischemia in the T2–T5 segments on the left, but not on the right or in control segments. EMG demonstrated increased amplitude for the T4–T5 segments. After LV sympathectomy, MPA and EMG evidence of increased muscle tone were absent. In conclusion, myocardial ischemia is associated with significant increased paraspinal muscle tone localized to the left side T4–T5 myotomes in neurally intact dogs. LV sympathectomy eliminates the somatic response, suggesting that sympathetic neural traffic between the heart and somatic musculature may function as the mechanism for the interaction.


Author(s):  
Nilanjan Ray

The concept of tourism has become one of the vital issues of economic and social benefits to the society. This present study identifies different motivational factors which may directly or indirectly influence the tourists' motivation. The primary objective of this study includes the growth, development and emergence of tourism potentials at Bhutan, in particular, as well as to analyze the tourist flow pattern and also examine the existing and future requirement in the motivational point of view. The major findings of this study show, in the present scenario of the above factors, how to attract more tourists for repeat visit and promoting infrastructural requirement for better tourism service to increase the level of tourists' motivation as well. In the policy implication point of view this study is relevant for balancing the demand and supply of tourism motivational requirement indicators which can offer better service excellence in the study area.


2001 ◽  
Vol 280 (5) ◽  
pp. L965-L973 ◽  
Author(s):  
Catherine Benoit ◽  
Barbara Renaudon ◽  
Dany Salvail ◽  
Eric Rousseau

Epoxyeicosatrienoic acids (EETs) are produced from arachidonic acid via the cytochrome P-450 epoxygenase pathway. EETs are able to modulate smooth muscle tone by increasing K+ conductance, hence generating hyperpolarization of the tissues. However, the molecular mechanisms by which EETs induce smooth muscle relaxation are not fully understood. In the present study, the effects of EETs on airway smooth muscle (ASM) were investigated using three electrophysiological techniques. 8,9-EET and 14,15-EET induced concentration-dependent relaxations of the ASM precontracted with a muscarinc agonist (carbamylcholine chloride), and these relaxations were partly inhibited by 10 nM iberiotoxin (IbTX), a specific large-conductance Ca2+-activated K+ (BKCa) channel blocker. Moreover, 3 μM 8,9- or 14,15-EET induced hyperpolarizations of −12 ± 3.5 and −16 ± 3 mV, with EC50 values of 0.13 and 0.14 μM, respectively, which were either reversed or blocked on addition of 10 nM IbTX. These results indicate that BKCa channels are involved in hyperpolarization and participate in the relaxation of ASM. In addition, complementary experiments demonstrated that 8,9- and 14,15-EET activate reconstituted BKCa channels at low free Ca2+ concentrations without affecting their unitary conductance. These increases in channel activity were IbTX sensitive and correlated well with the IbTX-sensitive hyperpolarization and relaxation of ASM. Together these results support the view that, in ASM, the EETs act through an epithelium-derived hyperpolarizing factorlike effect.


1989 ◽  
Vol 257 (4) ◽  
pp. H1315-H1320
Author(s):  
J. L. Mehta ◽  
D. L. Lawson ◽  
W. W. Nichols ◽  
P. Mehta

To determine the influence of polymorphonuclear leukocytes (PMNLs) on vascular smooth muscle tone, isolated human PMNLs (10(4)–10(7) cells/ml) were suspended in a tissue bath with precontracted rat aortic rings with or without endothelium. PMNLs in low concentrations (10(4) and 10(5) cells/ml) caused a mild contraction, and in higher concentrations (10(6) and 10(7) cells/ml) caused a modest relaxation of aortic rings with intact endothelium. In contrast, PMNLs caused a potent concentration-dependent relaxation of deendothelialized rings (P less than 0.01 compared with rings with intact endothelium). The PMNL-induced vascular smooth muscle relaxation was abolished by both hemoglobin and methylene blue and potentiated by both superoxide dismutase and captopril. Although suspension of PMNLs caused release of eicosanoids, thromboxane A2 and prostacyclin, from rings with intact endothelium, neither indomethacin nor the TxA2-endoperoxide receptor antagonist SQ 29548 modified the effects of PMNLs on vascular smooth muscle tone. These observations suggest that unstimulated PMNLs generate a smooth muscle relaxant, which has biological characteristics similar to the endothelium-derived relaxing factor. Since the activity of this PMNL-derived smooth muscle relaxant is more pronounced in deendothelialized vascular segments, it appears that endothelium provides a barrier against vasorelaxation by high concentrations of PMNLs.


2004 ◽  
Vol 286 (3) ◽  
pp. H1043-H1056 ◽  
Author(s):  
Nikolaos M. Tsoukias ◽  
Mahendra Kavdia ◽  
Aleksander S. Popel

Nitric oxide (NO) plays many important physiological roles, including the regulation of vascular smooth muscle tone. In response to hemodynamic or agonist stimuli, endothelial cells produce NO, which can diffuse to smooth muscle where it activates soluble guanylate cyclase (sGC), leading to cGMP formation and smooth muscle relaxation. The close proximity of red blood cells suggests, however, that a significant amount of NO released will be scavenged by blood, and thus the issue of bioavailability of endothelium-derived NO to smooth muscle has been investigated experimentally and theoretically. We formulated a mathematical model for NO transport in an arteriole to test the hypothesis that transient, burst-like NO production can facilitate efficient NO delivery to smooth muscle and reduce NO scavenging by blood. The model simulations predict that 1) the endothelium can maintain a physiologically significant amount of NO in smooth muscle despite the presence of NO scavengers such as hemoglobin and myoglobin; 2) under certain conditions, transient NO release presents a more efficient way for activating sGC and it can increase cGMP formation severalfold; and 3) frequency-rather than amplitude-dependent control of cGMP formation is possible. This suggests that it is the frequency of NO bursts and perhaps the frequency of Ca2+ oscillations in endothelial cells that may limit cGMP formation and regulate vascular tone. The proposed hypothesis suggests a new functional role for Ca2+ oscillations in endothelial cells. Further experimentation is needed to test whether and under what conditions in silico predictions occur in vivo.


2017 ◽  
Vol 11 (1) ◽  
pp. 527-538 ◽  
Author(s):  
Consuelo Sanavia ◽  
Marco Tatullo ◽  
Jessica Bassignani ◽  
Silvia Cotellessa ◽  
Giulia Fantozzi ◽  
...  

Background/Objective:The clinical conditions that lead to an alteration of the enamel structure are numerous. The diet high in sugars and acidifying substances, psychological stress that triggers parafunctional behaviors, the reduced intake of fiber-rich foods or alkalizing substances, together with other factors, contribute to demineralization of the tooth enamel. Dental mineralizing products on the current market are distinguished according to the dosage form, the active ingredient, the release technology, clinical indications and patient choice. Currently, it is necessary to propose to oral health professionals a guide to orient themselves in this chaotic choice, in order to prefer the most effective product for their own clinical target.Methods:Italian Society of Oral Hygiene Sciences-S.I.S.I.O. is one of the leading scientific Italian societies representing those dental hygienists working with high-quality standards and in agreement with scientific evidence: in the last year, the SISIO working group has carried out a study focused on remineralizing agents in dentistry, in order to give an authoritative point of view to indicate a guideline in the decision process of the choice of a remineralizing agent. We will report the results pointed out from the last consensus meeting in 2017.Results:We have reported the good the bad and the ugly have been discussed in a critical discussion of such topic.Conclusion:The SISIO experience has been reported in this position paper with the aim to serve as a useful aid in the daily choice of the clinical steps to perform, when dental professionals need to treat demineralized teeth.


Author(s):  
Ishan Verma ◽  
Laith Zori ◽  
Jaydeep Basani ◽  
Samir Rida

Abstract Modern aero-engines are characterized by compact components (fan, compressor, combustor, and turbine). Such proximity creates a complex interaction between the components and poses a modeling challenge due to the difficulties in identifying a clear interface between components since they are usually modeled separately. From a numerical point of view, the simulation of a complex compact aero-engine system requires interaction between these individual components, especially the combustor-turbine interaction. The combustor is characterized by a subsonic chemically reacting and swirling flow while the high-pressure turbine (HPT) stage has flow which is transonic. Furthermore, the simulation of combustor-turbine interactions is more challenging due to aggressive flow conditions such as non-uniform temperature, non-uniform total-pressure, strong swirl, and high turbulence intensity. The simulation of aero-engines, where combustor-turbine interactions are important, requires a methodology that can be used in a real engine framework while ensuring numerical requirements of accuracy and stability. Conventionally, such a simulation is carried out using one of the two approaches: a combined simulation (or joint-simulation) of the combustor and the HPT geometries, or a co-simulation between the combustor and the turbine with the exchange of boundary conditions between these two separate domains. The primary objective of this paper is to assess the effectiveness of the joint simulation versus the co-simulation and propose a more practical approach for modeling combustor and turbine interactions. First, a detailed grid independence study with hexahedral and polyhedral meshes is performed to select the required polyhedral mesh. Then, an optimal location of the interface between the combustor and the nozzle guide vane (NGV) is identified. Co-simulations are then performed by exchanging information between the combustor and the NGV at the interface, wherein the combustor is solved using LES while the NGV is solved using RANS. The joint combustor-NGV simulations are solved using LES. The effect of the combustor-NGV interaction on the flow field and hot streak migration is analyzed. The results suggest that the joint simulation is computationally efficient and more accurate since both components are modelled together.


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