Surface electromyography applications

The electrophysiological techniques (neurography and needle electromyography) allow us an approach to the knowledge of the neuromuscular function. Electromyography obtains the electrical activity from the muscle in rest or in contraction (maximum and static voluntary contraction) In its clinical application, electromyography helps to the diagnosis and follow-up of a process of neuromuscular type. On the other hand, kinesiological or surface electromyography (SEMG) allows the study of the muscular activity in dynamics, which we can apply to the biomechanical movement analysis, gait analysis, studies of muscular fatigue, sport performance| and applications in work medicine and ergonomics. SEMG brings advantages like the fact that is a bloodless test, of being able to analyze varying muscles at the same time, in motion and in actions of non limited duration. The processed one brings us parameters of amplitude and frequencies, which we will use for descriptive and comparative studies. As a balancing entry, it does not allow us to study deep musculature, and some aspects of definition are lost in the obtained outlines

Estudi de l'activitat muscular durant el relevé en primera i sisena posició

Fonaments: Conèixer les diferències existents en l'activació muscular durant el relevé. Participants i mètode: Divuit ballarines de ballet clàssic (14-32 anys). Es practica anàlisi cinètica i cinemàtica. S'analitza el grau de flexió plantar aconseguit i la participació de diversos músculs. Es comparen (test de Wilcoxon) els resultats obtinguts en executar el gest en sisena posició (en parallel) respecte de la primera (en déhors) i en primera posició correcta respecte de la primera posició amb pronació del peu. Resultats: El rang de flexió plantar aconseguit és millor en sisena posició que en primera, i millor en primera correcta que en primera pronada. El múscul bessó intern (BI) presenta més activitat en primera posició; l'abductor del dit gros (ADG), en paral·lel o sisena posició, i els peroneals i bessó extern (BE), en pronació del peu en primera posició. El peroneal lateral (PL) presenta diferències durant el relevé (en posició estàtica inicial i en fase ascendent) i l'ADG durant la pujada al relevé. El BI presenta una activació més precoç i d'inici més lent que el BE en la flexió plantar del relevé. Discussió: L'activitat de l'ADG en primera posició tradueix dèficit d'estabilitat de l'arc intern i del primer radi i, per tant, un major risc de lesió. El relevé en sisena posició permet millor grau de flexió plantar que en primera. La pronació del peu ­secundària en mala tècnica­ produeix menor flexió plantar. L'ADG treballa més en parallel que en déhors, tot evitant la rotació externa del maluc. Les diferències del PL es relacionen amb la presència de pronació del peu: treballa més en pronació

S-adenosyl-L-methionine protects the liver against the cholestatic, cytotoxic, and vasoactive effects of leukotriene D4: a study with isolated and perfused rat liver

Cysteinyl-leukotrienes can cause cholestasis and liver damage when administered at nanomolar concentrations. Using the isolated and perfused rat liver we analyzed whether S-adenosyl-L-methionine (SAMe) may protect this organ against the noxious effects of leukotriene-D4 (LTD4). We observed that a 2 nmol bolus of this compound decreased bile flow (-12.6% +/- 1.6%, P < .02), and bile salt excretion (-23.5% +/- 2.2%, P < .02; both compared with baseline values), caused the release of glutamic-oxaloacetic transaminase (GOT) and lactic dehydrogenase (LDH) to the hepatic effluent, and increased significantly the perfusion pressure as compared with a control group not receiving LTD4 (6.0 +/- 1.1 vs. 0.2 +/- 0.02 mm hg, respectively; P < .001). The cholestatic effect of LTD4 was attenuated by infusion of SAMe which, at rates of 67 and 100 microg/min, totally prevented the decrease in bile salt excretion. Likewise, in SAMe infused livers, the release to the effluent of GOT and LDH was lower than in the group receiving LTD4 only, and was even lower than in the control group. We also found that the increase in perfusion pressure induced by LTD4 was prevented by SAMe in a dose-dependent manner. Of interest, SAMe increased the biliary excretion of the eicosanoid in a dose-related fashion. We conclude that SAMe reverts the cholestatic, cytotoxic, and hemodynamic effects of LTD4 on the liver, and that these protective effects might be partly because of a stimulation of the biliary excretion of the leukotriene

Experiences and perceptions of final-year nursing students of using a chatbot in a simulated emergency situation: A qualitative study

Aim The aim of this study is to explore the experiences and perceptions of final-year nursing students on the acceptability and feasibility of using a chatbot for clinical decision-making and patient safety. Background The effective and inclusive use of new technologies such as conversational agents or chatbots could support nurses in increasing evidence-based care and decreasing low-quality services. Methods A descriptive qualitative study was used through focus group interviews. The data analysis was conducted using a thematic analysis. Results This study included 114 participants. After our data analysis, two main themes emerged: (i) experiences in the use of a chatbot service for clinical decision-making and and (ii) integrating conversational agents into the organizational safety culture. Conclusions The findings of our study provide preliminary support for the acceptability and feasibility of adopting SafeBot, a chatbot for clinical decision-making and patient safety. Our results revealed substantial recommendations for refining navigation, layout and content, as well as useful insights to support its acceptance in real nursing practice. Implications for Nursing Management Leaders and managers may well see artificial intelligence-based conversational agents like SafeBot as a potential solution in modern nursing practice for effective problem-solving resolution, innovative staffing and nursing care delivery models at the bedside and criteria for measuring and ensure quality and patient safety.Funding for open access charge: CRUE-Universitat Jaume

Heart morphology differences induced by intrauterine growth restriction and premature birth measured on the ECG in pre-adolescents

Pre-adolescents who had suffered from intrauterine growth restriction (IUGR) during their mothers'' pregnancy usually present more spherical hearts (smaller relation between base to apex measure and basal diameter), measured using echocardiograms, which has been associated with long-term cardiac disfunction. The present work aims to analyse these heart morphology changes by means of the surface ECG so as to have an early diagnostic tool of this pathology. The dataset is conformed by 148 pre-adolescents with either preterm or term births, and with or without IUGR. Once QRS and T-wave loops were obtained from the vectorcardiogram, the angles between the dominant vector of the QRS loop and -XY or -YZ planes(FR-XY, FR-YZ) and the difference between FR-XY and the angle between the dominant vector of T-wave loop (FT-XY) and the XY-plane showed different values for pre-adolescents who suffered from premature birth and IUGR than for control subjects (p < 0.05). These characteristics can open the door for a much easier diagnosis and follow-up of candidates for these disfunctions

Taurocholate-stimulated leukotriene C4 biosynthesis and leukotriene C4-stimulated choleresis in isolated rat liver

BACKGROUND/AIMS: Cysteinyl-containing leukotrienes seem to exert a cholestatic effect. However, leukotriene inhibitors were found to reduce bile salt efflux in isolated rat hepatocytes, suggesting a role for leukotrienes in bile flow formation. METHODS: In the isolated rat liver, the effects of two different concentrations of leukotriene C4 on bile flow and bile salt excretion are analyzed, as well as the possible effect of taurocholate on the hepatic production of cysteinyl-containing leukotrienes. RESULTS: Leukotriene C4 (0.25 fmol) increased bile salt excretion (+22.2%; P < 0.05), whereas a much higher dose (0.25 x 10(6) fmol) showed the known cholestatic effect, reducing bile salt excretion (-25.9%; P < 0.01). These dose-dependent biphasic effects were specific because they could be prevented by the simultaneous administration of cysteinyl-containing leukotriene antagonists. On the other hand, taurocholate administration induced a dose-dependent increase in biliary excretion of cysteinyl-containing leukotrienes. Furthermore, taurocholate increased messenger RNA levels of 5-lipoxygenase, a key enzyme in leukotriene biosynthesis. Taurocholate increase of hepatocyte intracellular calcium was not significant, suggesting that taurocholate effects are not mediated by stimulation of calcium metabolism. CONCLUSIONS: These results constitute evidence for the existence of a positive feedback mechanism by which bile salts stimulate the synthesis of leukotrienes that, in turn, stimulate bile salt excretion

Renal prostacyclin influences renal function in non-azotemic cirrhotic patients treated with furosemide

The influence of prostaglandins on renal function changes induced by furosemide was analyzed in 21 non-azotemic cirrhotic patients with ascites. Patients were studied in two periods of 120 min immediately before and after furosemide infusion (20 mg, ev). Furosemide caused an increase in creatinine clearance in 15 patients (group A: 99 +/- 7 vs. 129 +/- 5 ml/min; mean +/- S.E.) and a reduction in the remaining six (group B: 102 +/- 13 vs. 71 +/- 9 ml/min). Parallel changes were observed in the urinary excretion of 6-Keto-prostaglandin-F1 alpha (metabolite of renal prostacyclin) which augmented after furosemide in 14 of the 15 patients from group A (478 +/- 107 vs. 1034 +/- 159 pg/min, p less than 0.001) and decreased in all patients from group B (1032 +/- 240 vs. 548 +/- 136 pg/min, p less than 0.05). In contrast, the urinary excretion of prostaglandin E2 was stimulated by furosemide in all patients (group A, 92 +/- 19 vs. 448 +/- 60 pg/min, p less than 0.001; and group B, 209 +/- 63 vs. 361 +/- 25 pg/min, p less than 0.05). In all of the patients furosemide-induced changes (post- minus pre-furosemide values) in creatinine clearance were closely correlated in a direct and linear fashion with those in 6-Keto-prostaglandin-F1 alpha (r = 0.74; p less than 0.001). These changes were associated with a higher furosemide-induced natriuresis in group A than in group B (641 +/- 68 vs. 302 +/-- 46 mumol/min, p less than 0.001

Altered liver gene expression in CCl4-cirrhotic rats is partially normalized by insulin-like growth factor-I

We have previously shown that the administration of low doses of insulin-like growth factor-I (IGF-I) to CCl4-cirrhotic rats improves liver function and reduces fibrosis. To better understand the mechanisms behind the hepatoprotective effects of IGF-I, and to identify those genes whose expression is affected in cirrhosis and after IGF-1 treatment, we have performed differential display of mRNA analysis by means of polymerase chain reaction (PCR) in livers from control and CCl4-cirrhotic rats treated or not with IGF-I. We have identified 16 genes that were up- or down-regulated in the cirrhotic liver. IGF-I treatment partially normalized the expression of eight of these genes, including serine proteinase inhibitors such as serpin-2 and alpha-1-antichymotripsin, alpha-1-acid glycoprotein, and alpha-2u-globulin. Additionally, we show that IGF-I enhanced the regenerative activity in the cirrhotic liver, as determined by the increased expression of the proliferating cell nuclear antigen (PCNA). Finally, IGF-I treatment partially restored the expression of growth hormone receptor (GHR) and the levels of global genomic DNA methylation, which are reduced in human and experimental cirrhosis. Taken together, our observations confirm the hepatoprotective effects of IGF-I, and suggest that this action can be exerted in part through the normalization of liver gene expression, growth hormone (GH) responsiveness and global genomic DNA methylation

Expression of insulin-like growth factor I by activated hepatic stellate cells reduces fibrogenesis and enhances regeneration after liver injury

BACKGROUND/AIM: Hepatic stellate cells (HSCs) express alpha-smooth muscle actin (alphaSMA) and acquire a profibrogenic phenotype upon activation by noxious stimuli. Insulin-like growth I (IGF-I) has been shown to stimulate HSCs proliferation in vitro, but it has been reported to reduce liver damage and fibrogenesis when given to cirrhotic rats. METHODS: The authors used transgenic mice (SMP8-IGF-I) expressing IGF-I under control of alphaSMA promoter to study the influence of IGF-I synthesised by activated HSCs on the recovery from liver injury. RESULTS: The transgene was expressed by HSCs from SMP8-IGF-I mice upon activation in culture and in the livers of these animals after CCl4 challenge. Twenty four hours after administration of CCl4 both transgenic and wild type mice showed similar extensive necrosis and increased levels of serum transaminases. However at 72 hours SMP8-IGF-I mice exhibited lower serum transaminases, reduced hepatic expression of alphaSMA, and improved liver morphology compared with wild type littermates. Remarkably, at this time all eight CCl4 treated wild type mice manifested histological signs of liver necrosis that was severe in six of them, while six out of eight transgenic animals had virtually no necrosis. In SMP8-IGF-I mice robust DNA synthesis occurred earlier than in wild type animals and this was associated with enhanced production of HGF and lower TGFbeta1 mRNA expression in the SMP8-IGF-I group. Moreover, Colalpha1(I) mRNA abundance at 72 hours was reduced in SMP8-IGF-I mice compared with wild type controls. CONCLUSIONS: Targeted overexpression of IGF-I by activated HSCs restricts their activation, attenuates fibrogenesis, and accelerates liver regeneration. These effects appear to be mediated in part by upregulation of HGF and downregulation of TGFbeta1. The data indicate that IGF-I can modulate the cytokine response to liver injury facilitating regeneration and reducing fibrosis