scholarly journals High Frequency Non-Invasive Stimulation Over the Spine: Effects on Mood and Mechanical Pain Tolerance in Normal Subjects

1997 ◽  
Vol 10 (2-3) ◽  
pp. 61-65 ◽  
Author(s):  
A. D. Towell ◽  
D. Williams ◽  
S. G. Boyd
Keyword(s):  
High Intensity ◽  
High Frequency ◽  
Healthy Subjects ◽  
Normal Subjects ◽  
Pain Tolerance ◽  
Left Shoulder ◽  
Cutaneous Stimulation ◽  
Non Invasive ◽  
Low Intensity ◽  
Clinical Pain

We investigated the effects of non-invasive high frequency (625Hz) stimulation over the spine on mechanical pain tolerance and subjective mood. Sixty healthy subjects were divided equally into three groups receiving either high intensity (250 V), low intensity (3–4 V) or sham electrical stimulation directly over the spinal cord for 30 minutes. Following high intensity stimulation, subjects felt significantly more elated, leisurely and less tense and, contrary to reports on patients with clinical pain, had lower mechanical pain tolerances. There were no correlations between changes in mood and changes in mechanical pain tolerances. These findings contrasted with the lack of any significant differences in mood or mechanical pain tolerances in a second study where 20 subjects received either high intensity or sham stimulation across the left shoulder joint. The results indicate that decreases in mechanical pain tolerance are independent of changes in mood following non-invasive high frequency, high intensity cutaneous stimulation but that both effects are dependent on that stimulation being applied over the spine.

Distraction and Redefinition in the Reduction of Low and High Intensity Experimentally-Induced Pain

1987 ◽  
Vol 7 (2) ◽  
pp. 155-164 ◽  
Author(s):  
Debora L. Dubreuil ◽  
Norman S. Endler ◽  
Nicholas P. Spanos
Keyword(s):  
Short Duration ◽  
High Intensity ◽  
Pain Tolerance ◽  
Pressure Pain ◽  
Low Intensity ◽  
Pain Ratings ◽  
Lower Pain ◽  
Intensity Condition ◽  
Experimentally Induced

Subjects underwent either low intensity or high intensity acute focal pressure pain of relatively short duration on a baseline and posttest trial. On the posttest subjects in each intensity condition either engaged in distraction (shadowing letters), attended to sensations (redefinition) or were given no treatment (controls). Distraction was more effective than redefinition at reducing rated pain and at enhancing pain tolerance for subjects in the high intensity condition. Subjects who scored as repressors gave lower pain ratings than sensitizers. Moreover, in the high intensity condition repressors given distraction reported significant increases in pain tolerance while sensitizers given distraction showed no changes in tolerance.

Measuring esophageal distension by high-frequency intraluminal ultrasound probe

2002 ◽  
Vol 283 (4) ◽  
pp. G886-G892 ◽  
Author(s):  
Poong-Lyul Rhee ◽  
Jianmin Liu ◽  
James L. Puckett ◽  
Ravinder K. Mittal
Keyword(s):  
High Frequency ◽  
Healthy Subjects ◽  
Normal Subjects ◽  
Ultrasound Images ◽  
Agarose Gel ◽  
Ultrasound Probe ◽  
Cross Sectional ◽  
Esophageal Sphincter

Distension of the esophagus can cause heartburn and chest pain; however, none of the available techniques to study the esophagus measure esophageal distension. We evaluated the technique of high-frequency intraluminal ultrasound probe (HFIUS) to measure the esophageal cross-sectional area (CSA) during gastroesophageal reflux (GER). The following methods were used: 1) the CSA of agarose gel tubes of known dimensions were measured using ultrasound probes; 2) seven normal subjects were studied to evaluate the esophageal CSA during different bolus volumes (1, 5, 10, 15, and 20 ml) of water swallows (WS); and 3) simultaneous pressures, pH, and ultrasound images of the esophagus were recorded in healthy subjects. In vitro studies showed that the HFIUS measured the CSA of the tubes accurately. The maximal CSA of the distal esophagus during WS with boluses of 1, 5, 10, 15, and 20 ml were 54, 101, 175, 235, and 246 mm2, respectively. Esophageal contents during 62 episodes of transient lower esophageal sphincter relaxations, 29 pH positive, and 33 pH negative GER episodes revealed that reflux of air into the esophagus occurred more frequently than liquid. The median CSA and estimated diameter of the esophagus during liquid GER was 44.1 mm2 and 7.5 mm, respectively. We conclude that HFIUS is a valid technique to measure the CSA of the esophagus in vivo during GER. Distension of the esophagus during physiological GER is relatively small.

scholarly journals Sound Performances of Partition Board from Waste Materials

2021 ◽  
Vol 920 (1) ◽  
pp. 012011
Author(s):  
U Kassim ◽  
S A Nur ◽  
M N Kamarudin ◽  
M A Rahim
Keyword(s):  
Noise Reduction ◽  
High Intensity ◽  
High Frequency ◽  
Low Frequency ◽  
Test Point ◽  
Sound Level ◽  
Waste Materials ◽  
Horizontal Line ◽  
Low Intensity ◽  
Reduction Coefficient

Abstract This study is on the sound performances of a selected number of partition boards in Industrialised Building System (IBS) buildings. The proposed bespoke board were made from squandered or waste materials, namely, coconut shells and newspapers. Each board had been tested for six different distances from the speaker in four different levels of sound, changing the level of the sound frequency. Thereon, the results were analysed. The average result of each board with various distances from the sound source, starting from 0 cm to 220 cm, was combined into under one sound level. The percentage of the noise reduction coefficient is designated by the vertical line whereas the levels of the sound is designated by the horizontal line. Point 1 stands for the low frequency and low intensity test. Point 2 stands for low frequency and high intensity test. The board that is being made of 80% coconut shell, 15% cement and 5% newspaper has an average of noise reduction coefficient of 0.21 in low frequency and low intensity, 0.21 in low frequency and high intensity, 0.24 in high frequency, high intensity and 0.12 in high frequency low intensity.

scholarly journals Movement and impact characteristics of South African professional rugby union players

2016 ◽  
Vol 27 (2) ◽  
pp. 33 ◽  
Author(s):  
J C Tee
Keyword(s):  
South African ◽  
High Intensity ◽  
Team Sports ◽  
Movement Analysis ◽  
Rugby Union ◽  
Non Invasive ◽  
Low Intensity ◽  
Movement Characteristics ◽  
Impact Characteristics ◽  
Time Movement

Background. Global positioning system (GPS) technology can provide accurate, non-invasive, real-time movement analysis of playersparticipating in team sports. The application of this technology to rugby union will improve training practices by allowing improvedunderstanding of movement characteristics and more individualised programmes.Objectives. To characterise the movement and impact patterns of South African professional rugby union players during match play andcompare these to previously reported data.Methods. Nineteen professional rugby players were tracked using GPS systems during 24 matches during the 2013 rugby season. Playerswere grouped as (i) backs or forwards and (ii) tight forwards, loose forwards, scrumhalves, inside backs or outside backs. Movements werecategorised in speed zones corresponding to walking (0 - 2 m.s-1), jogging (2 - 4 m.s-1), striding (4 - 6 m.s-1) and sprinting (>6 m.s-1). Walkingand jogging were classified as low-intensity and striding and sprinting as high-intensity movement zones. An inbuilt triaxial accelerometer(sampling frequency 100 Hz) measured the total impacts >5G and high-intensity impacts >8G. All data were normalised to time on fieldand reported as mean (standard deviation).Results. There was no difference between forwards and backs in relative distance covered. Backs reached higher maximum speeds thanforwards (backs 8.8 (1.1) v. forwards 7.6 (1.3) m.s-1, effect size (ES) 1.0, and outside backs were the fastest positional group (9.4 (0.9)m.s-1, ES 0.4 - 2.2). Players in all positions spent the majority of time walking (79 - 84%). Backs covered more distance than forwards inhigh-intensity speed zones (forwards 11 (5) v. backs 14 (4) m.min-1, ES 0.7). Tight forwards covered the most distance in low-intensityzones (63 (6) m.min-1, ES 0.3 - 1.7) while scrumhalves ran the most distance in high-intensity zones (20 (5) m.min-1, ES 1.2 - 3.6). Highintensity: low-intensity running ratios ranged from 1:13 (tight forwards) to 1:3 (scrumhalves). Loose forwards and inside backs exhibitedsimilar movement patterns. There was no difference in impact variables between forwards and backs. Inside backs sustained the least totalimpacts (6.5 (1.2) >5G.min-1, ES 0.9 - 2.0) and high-intensity impacts (0.7 (0.2) >8G.min-1, ES 0.5 - 1.4).Conclusions. There were notable differences in the movement of professional rugby union players in different positions, and effectivetraining programmes should reflect these variations.

Appropriate electrode sites and electrical characteristics for TENS

2014 ◽  
Keyword(s):  
Social Factors ◽  
High Intensity ◽  
High Frequency ◽  
Low Frequency ◽  
Electrical Characteristics ◽  
Nerve Fibres ◽  
Low Intensity ◽  
Factors Influencing ◽  
Electrode Positioning ◽  
Low Threshold

The success of TENS treatment depends on the use of safe and appropriate TENS technique. Uncertainty about optimal TENS technique is due in part to the variety of possible electrode positions and electrical characteristics that can be chosen for treatment. Conventional TENS uses low-intensity, high-frequency currents to activate low-threshold afferent nerve fibres in the skin. AL-TENS uses high-intensity, low-frequency currents to generate non-painful phasic muscle contractions (twitching). The purpose of this chapter is to discuss the principles that underpin the use of safe and appropriate electrode sites and electrical characteristics during TENS. The chapter covers how to choose between conventional and AL-TENS, the appropriate electrode positioning for conventional TENS and AL-TENS including instances where AL-TENS may be more beneficial than conventional TENS, appropriate choice of electrical characteristics for stimulation, and biological, psychological, and social factors influencing response to TENS

scholarly journals Predictability modulates the anticipation and perception of pain in both self and others

2019 ◽  
Vol 14 (7) ◽  
pp. 747-757 ◽  
Author(s):  
Weiwei Peng ◽  
Xiaoxuan Huang ◽  
Yang Liu ◽  
Fang Cui
Keyword(s):  
High Intensity ◽  
High Frequency ◽  
Neural Circuits ◽  
Event Related Potentials ◽  
Subjective Ratings ◽  
Behavioral Ratings ◽  
Oscillation Power ◽  
Low Intensity ◽  
Related Potentials ◽  
Perception Of Self

AbstractPredictability has been suggested to modulate both the anticipation and perception of self-pain. Considering the overlapping neural circuits between self-pain and other-pain perceptions, the present study investigated how the predictability of forthcoming pain modulates the anticipation and perception of self-pain and other-pain. We used a balanced, within-participant experimental design in which a visual cue indicating the recipient, intensity and predictability of an upcoming painful electrical stimulation was presented before its delivery. Subjective ratings and electroencephalography activities to the anticipation and perception of self-pain and other-pain were recorded and compared between certain and uncertain conditions. Results showed that predictability affected the perception of self-pain and other-pain in a similar manner such that the differences in behavioral ratings and event-related potentials to high-intensity and low-intensity pain were significantly reduced when the intensity was uncertain. The strengths of predictability-induced modulation of self-pain and other-pain perceptions were positively correlated with each other. Furthermore, predictability also modulated the anticipation of both self-pain and other-pain such that pre-stimulus high-frequency α-oscillation power at sensorimotor electrodes contralateral to the stimulation side was maximally suppressed when anticipating certain high-intensity pain. These findings demonstrate that predictability-induced modulation on pain anticipation and perception was similarly applied to both self-pain and other-pain.

Transcutaneous electrical stimulation applied to the infratrochlear nerve induces a homatropine-resistant miosis in humans

1990 ◽  
Vol 78 (5) ◽  
pp. 457-462 ◽  
Author(s):  
B. M. Fusco ◽  
M. Alessandri ◽  
V. Campagnolo ◽  
M. Fanciullacci
Keyword(s):  
Electrical Stimulation ◽  
High Intensity ◽  
Healthy Subjects ◽  
Time Course ◽  
Contralateral Side ◽  
Pupillary Response ◽  
Transcutaneous Electrical Stimulation ◽  
Antidromic Activation ◽  
Light Reflex ◽  
Low Intensity

1. Both high- and low-intensity transcutaneous electrical stimuli were applied to the emergence of the infratrochlear nerve in 18 healthy subjects. The effect on the size of the homolateral pupil was investigated. The width of the pupil was also measured when high-intensity transcutaneous electrical stimulation was applied to the contralateral side. 2. The high-intensity pulse resulted in constriction of the pupil when the stimulation was homolateral. The miosis was slow in onset (120 s latency) and long-lasting (80 s). No pupillary changes were detected after either ipsilateral low-intensity or contralateral high-intensity stimuli. 3. In 11 healthy subjects, the pupillary response to transcutaneous electrical stimulation was evaluated during iris parasympathetic blockade induced by homatropine eyedrops. The disappearance of the light reflex due to homatropine was considered an index of the parasympathetic blockade. Afterwards, a high-intensity pulse was transcutaneously delivered to the emergence of the infratrochlear nerve and the ipsilateral pupil size was measured. 4. A reduction in the pupillary size followed the electrical stimulation, still under the effect of homatropine which abolished the light reflex. The time course of this pupillary constriction was similar to that seen without the influence of homatropine. 5. The findings suggest that homolateral miosis, observed after unilateral high-intensity stimulation of the infratrochlear nerve, does not stem from cholinergic activation. It has been suggested that miosis induced by transcutaneous electrical stimulation may be due to an antidromic activation of the iris sensory fibres.

Responses of Platelets to Strains of Streptococcus sanguis: Findings in Healthy Subjects, Bernard-Soulier, Glanzmann’s, and Collagen-Unresponsive Patients

1987 ◽  
Vol 57 (02) ◽  
pp. 222-225 ◽  
Author(s):  
A H Soberay ◽  
M C Herzberg ◽  
J D Rudney ◽  
H K Nieuwenhuis ◽  
J J Sixma ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Healthy Subjects ◽  
Normal Subjects ◽  
Membrane Glycoprotein ◽  
Response Mechanism ◽  
Platelet Response ◽  
Induce Platelet Aggregation ◽  
Streptococcus Sanguis ◽  
Lag Times ◽  
Bernard Soulier Syndrome

SummaryThe ability of endocarditis and dental strains of Streptococcus sanguis to induce platelet aggregation in plasma (PRP) from normal subjects were examined and compared to responses of PRP with known platelet membrane glycoprotein (GP) and response defects. S. sanguis strains differed in their ability to induce normal PRPs to aggregate. Strains that induced PRP aggregation in more than 60% of donors were significantly faster agonists (mean lag times to onset of aggregation less than 6 min) than those strains inducing response in PRPs of fewer than 60% of donors.Platelets from patients with Bernard-Soulier syndrome aggregated in response to strains of S. sanguis. In contrast, platelets from patients with Glanzmann’s thrombasthenia and from a patient with a specific defect in response to collagen were unresponsive to S. sanguis. These observations show that GPIb and V are not essential, but GPIIb-IIIa and GPIa are important in the platelet response mechanism to S. sanguis. Indeed, the data suggests that the platelet interaction mechanisms of S. sanguis and collagen may be similar.

Inhibition rather than Enhancement of Hemostatic System Activation during Initiation of Oral Anticoagulant Treatment

1997 ◽  
Vol 77 (04) ◽  
pp. 685-689 ◽  
Author(s):  
Paul A Kyrle ◽  
Johannes Brockmeier ◽  
Ansgar Weltermann ◽  
Sabine Eichinger ◽  
Wolfgang Speiser ◽  
...  
Keyword(s):  
High Intensity ◽  
Oral Anticoagulant ◽  
Protein C ◽  
Venous Blood ◽  
Rapid Decline ◽  
Oral Anticoagulant Treatment ◽  
Shed Blood ◽  
Low Intensity ◽  
Hemostatic System ◽  
System Activation

SummaryCoumarin-induced skin necrosis is believed to be due to a transient hypercoagulable state resulting from a more rapid decline of the protein C activity relative to that of coagulation factors (F) II, IX and X during initiation of oral anticoagulant therapy. We studied hemostatic system activation during early oral anticoagulant treatment with a technique that investigates coagulation activation in the microcirculation.We determined in 10 healthy volunteers the concentrations of prothrombin fragment F1+2 (f1.2) and thrombin-antithrombin complex (TAT) in blood emerging from an injury of the microvasculature (bleeding time incision) before and after initiation of both high-inten- sity and low-intensity coumarin therapy. In addition, f1.2, TAT, activated F VII (F Vila) and the activities of FII, F VII, F X and protein C were measured in venous blood.A rapid decline of F VII and protein C was observed in venous blood with activities at 24 h of 7 ± 1% and 43 ± 2%, respectively, during the high-intensity regimen. A 20 to 30% reduction of f1.2 and TAT was seen in venous blood at 72 h with no major difference between the high- and the low-intensity regimen. F Vila levels were substantially affected by anticoagulation with a >90% reduction at 48 h during the high-intensity regimen. Following high-intensity coumarin, a >50% decrease in the fl.2 and TAT levels was found in shed blood at 48 h suggesting substantial inhibition of thrombin generation during early oral anticoagulation. An increase in the f1.2 and TAT levels was seen neither in shed blood nor in venous blood.Our data do not support the concept of a transient imbalance between generation and inhibition of thrombin as the underlying pathomechanism of coumarin-induced skin nekrosis.

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