Search results for "Stimulation"

The role of bestatin, an inhibitor of cell surface proteases, in the interaction of serum with untransformed cells in culture.

1981

Bestatin is an inhibitor of cell surface-associated aminopeptidase B and leucine aminopeptidase. This microbial product simulates the role of serum as an activator of uridine uptake in quiescent BHK cells. The compound significantly stimulates the incorporation of labelled thymidine into the acid-insoluble fraction of serum-starved Nil 8 cells in the presence of low concentration of serum. The possible mechanisms of these interactions are discussed.

Online Closed-Loop Real-Time tES-fMRI for Brain Modulation: Feasibility, Noise/Safety and Pilot Study

2021

AbstractRecent studies suggest that transcranial electrical stimulation (tES) can be performed during functional magnetic resonance imaging (fMRI). The novel approach of using concurrent tES-fMRI to modulate and measure targeted brain activity/connectivity may provide unique insights into the causal interactions between the brain neural responses and psychiatric/neurologic signs and symptoms, and importantly, guide the development of new treatments. However, tES stimulation parameters to optimally influence the underlying brain activity in health and disorder may vary with respect to phase, frequency, intensity and electrode’s montage. Here, we delineate how a closed-loop tES-fMRI study of …

Judging the contact-times of multiple objects: Evidence for asymmetric interference.

2009

The accuracy of time-to-contact (TTC) judgments for single approaching objects is well researched, however, close to nothing is known about our ability to make simultaneous TTC judgments for two or more objects. Such complex judgments are required in many everyday situations, for instance when crossing a multi-lane street or when engaged in multi-player ball games. We used a prediction-motion paradigm in which participants simultaneously estimated the absolute TTC of two objects, and compared the performance to a standard single-object condition. Results showed that the order of arrival of the two objects determined the accuracy of the TTC estimates: Estimation of the first-arriving object …

Early stimulation: psychomotor development of two girls with Aicardi syndrome.

1987

Summary The psychomotor development achieved by two girls with the Aicardi syndrome is described. Until now this syndrome has been considered to produce a total dissociation from the environment in those affected. The results of early intervention, although not spectacular, are sufficient to recommend early stimulation in these children.

Differences in cardiorespiratory and neuromuscular responses between voluntary and stimulated contractions of the quadriceps femoris muscle.

2006

The aim of this study was to compare respiratory gas exchange variables and muscle fatigue between equal-intensity (i.e., same force output) electrostimulated and voluntary contractions of the quadriceps muscle (46+/-10% of maximal voluntary force). Twelve healthy men served as volunteers. Oxygen consumption, ventilation and respiratory exchange ratio were recorded during the exercise bouts. Muscle fatigue was quantified as the exercise-induced reduction in maximal voluntary force. The average oxygen consumption (11+/-3 versus 8+/-2 mL min(-1)kg(-1)), ventilation (23+/-4 versus 16+/-2 L min(-1)) and respiratory exchange ratio (0.96+/-0.02 versus 0.85+/-0.01) were significantly higher during…

Response to Anti-human IgE in Human Pulmonary Arteries: Regulation by Endothelium

1993

Initial reports concerning anaphylactic reactions in the lung have demonstrated that histamine is released, and this mediator may be responsible for the severe hypotension observed in vivo in sensitized animals. However, those mechanisms involved in the antigen-vascular interactions have not been elucidated. Human isolated pulmonary arterial preparations relaxed when challenged with anti-human IgE (a-IgE). This response was associated with a release of histamine and PGI2. Both the relaxation and the release of PGI2 were attenuated by removal of the endothelium or by prior treatment of the tissues with chlorpheniramine. Indomethacin also significantly reduced the relaxations produced by a-Ig…

Influence of endothelial nitric oxide on neurogenic contraction of human pulmonary arteries.

1995

The present study was designed to investigate the contribution of the endothelium and that of the L-arginine pathway on the contractile responses of isolated human pulmonary arteries to electrical field stimulation (EFS) and noradrenaline. Isometric tension was measured in artery rings obtained from portions of human lung after thoracic surgery for removal of lung carcinoma (18 patients). Electrical field stimulation (EFS) induced frequency-dependent contractions of isolated human pulmonary arteries which were abolished by tetrodotoxin, guanethidine and prazosin (all at 10(-6) M). The increases in tension were of greater magnitude in arteries denuded of endothelium. NG-nitro-L-arginine meth…

Evidence for a negative inotropic effect of obesity in human myocardium?

2009

Objective: The present study was performed as an attempt to analyze the relationship between body weight and human myocardial performance. As overweight is frequently associated with hypertension, stenosis of epimyocardial coronary arteries and other factors that influence myocardial performance, the experimental model of isolated human atrial myocardium was selected. Atrial contractile performance does neither depend on the extent of stenosis of epicardial coronary arteries nor on the degree of hypertension and its secondary pathology. Methods:Rightatrialmusclepreparations(0.5 6 mm)of183patientsundergoingcoronaryarterybypasssurgerywereelectricallystimulatedat optimal length. Active tension…

2015

In a recently performed survey with 4000 randomly selected persons, 68 (7.2 %) of 948 respondents reported intolerance and/or allergy-like symptoms to wine. The aim of this study was to analyze whether a real sensitization to wine proteins could be confirmed by diagnostic and/or immunological settings. For this purpose, 19 subjects with self-reported intolerance to wine of the invited subjects and 10 controls without a history of intolerance participated in an allergological examination (skin prick test, ImmunoCAP for determination of specific IgE antibodies, CAST for testing basophil activation, ImmunoBlot for testing specificity of IgE-antibodies). For the allergological work-up red and w…

Alternative mechanisms for tiotropium

2009

Tiotropium is commonly used in the treatment of chronic obstructive pulmonary disease. Although largely considered to be a long-acting bronchodilator, its demonstrated efficacy in reducing the frequency of exacerbations and preliminary evidence from early studies indicating that it might slow the rate of decline in lung function suggested mechanisms of action in addition to simple bronchodilation. This hypothesis was examined in the recently published UPLIFT study and, although spirometric and other clinical benefits of tiotropium treatment extended to four years, the rate of decline in lung function did not appear to be reduced by the addition of tiotropium in this study. This article summ…