Painful cold-heat segmental pulse stimulation provokes the thermal pain illusion

© 2020, The Author(s), under exclusive licence to Springer Nature Limited. Understanding ethnic differences in pain is important for addressing disparities in pain care. A common belief is that African Americans are hyposensitive to pain compared to Whites, but African Americans show increased pain sensitivity in clinical and laboratory settings. The neurobiological mechanisms underlying these differences are unknown. We studied an ethnicity- and gender-balanced sample of African Americans, Hispanics and non-Hispanic Whites using functional magnetic resonance imaging during thermal pain. Higher pain report in African Americans was mediated by discrimination and increased frontostriatal circuit activations associated with pain rating, discrimination, experimenter trust and extranociceptive aspects of pain elsewhere. In contrast, the neurologic pain signature, a neuromarker sensitive and specific to nociceptive pain, mediated painful heat effects on pain report largely similarly in African American and other groups. Findings identify a brain basis for higher pain in African Americans related to interpersonal context and extranociceptive central pain mechanisms and suggest that nociceptive pain processing may be similar across ethnicities.

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Nano-Pulse Stimulation (NPS) in Seborrheic Keratosis Study

Case Medical Research ◽

10.31525/ct1-nct03846531 ◽

2000 ◽

Author(s):

Keyword(s):

Seborrheic Keratosis ◽

Pulse Stimulation

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Nano-Pulse Stimulation (NPS) in Seborrheic Keratosis Optimization Study

Case Medical Research ◽

10.31525/ct1-nct04249115 ◽

2020 ◽

Author(s):

Keyword(s):

Seborrheic Keratosis ◽

Optimization Study ◽

Pulse Stimulation

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ANALGESIC AND ANTI-INFLAMMATORY EFFECTS OF ACETYLSALICYLIC ACID: PHYSIOLOGICAL MECHANISMS

Scientific Notes of V.I. Vernadsky Crimean Federal University. Biology. Chemistry ◽

10.37279/2413-1725-2020-6-1-197-219 ◽

2020 ◽

Vol 6(72) (1) ◽

pp. 197-219

Author(s):

I. V. Cheretaev ◽

D. R. Khusainov ◽

E. N. Chuyan ◽

M. Yu. Ravaeva ◽

A. N. Gusev ◽

...

Keyword(s):

Acetylsalicylic Acid ◽

Physiological Mechanism ◽

The Body ◽

Physiological Mechanisms ◽

Scientific Publications ◽

Thermal Pain ◽

Order Of Magnitude ◽

Anti Inflammatory ◽

Number Of Publications ◽

Electrical Stimuli

The purpose of the review is to summarize current literature data and the results of our own research on the analgesic and anti-inflammatory effects of acetylsalicylic acid, as well as the physiological mechanisms underlying them. This acid is the most studied reference representative of salicylates, which is convenient to consider the physiological effects characteristic in general for this group of chemical and medicinal products. Acetylsalicylic acid has analgesic properties against thermal pain and pain caused by electrical stimuli, as well as a pronounced anti-inflammatory effect. The realization of these properties depends on the peculiarities of aspirin metabolism in the body, ion and synaptic mechanisms for controlling the functional state of the cell, neurotransmitter systems of the сentral nervous system, and mechanisms of peripheral and сentral analgesia. Analgesic properties of acetylsalicylic acid founded not only in normal, but also in ultra-small doses. Various physical and especially chemical factors significantly change their effects. This increases the interest in studying the analgesic activity of salicylates and their physiological mechanisms, since such studies can serve as a basis for creating new non-steroidal anti-inflammatory drugs with low toxicity and high safety for patients, and improve the strategy of their practical use. Currently, the most detailed study of the physiological mechanism of analgesic and anti-inflammatory action of aspirin and its main metabolite – salicylic acid. However, it should be note that despite the abundance of existing data obtained in scientific studies of the effects of aspirin and its practical use, there are a number of unexplained aspects of the action of this drug, the mechanism of which has not yet been deciphered. The continuing interest in the effects and mechanisms of action of this drug and in connection with the expansion of its use evidenced by a consistently high number of scientific publications on aspirin in the most famous foreign and domestic publications. At the same time, the number of publications about aspirin is an order of magnitude higher than about any other drug known to humanity.

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Reference values of mechanical and thermal pain tests in a pain-free population

European Journal of Pain ◽

10.1016/j.ejpain.2010.08.011 ◽

2011 ◽

Vol 15 (4) ◽

pp. 376-383 ◽

Cited By ~ 106

Author(s):

Alban Y. Neziril ◽

Pasquale Scaramozzinol ◽

Ole K. Andersenl ◽

Anthony H. Dickensonl ◽

Lars Arendt-Nielsenl ◽

...

Keyword(s):

Reference Values ◽

Thermal Pain ◽

Pain Tests

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The subjective sensation induced by various thermal pulse stimulation in healthy volunteers

Scandinavian Journal of Pain ◽

10.1016/j.sjpain.2017.04.039 ◽

2017 ◽

Vol 16 (1) ◽

pp. 177-178

Author(s):

Y. Oono ◽

H. Kubo ◽

T. Imamura ◽

K. Matsumoto ◽

S. Uchida ◽

...

Keyword(s):

Healthy Volunteers ◽

Thermal Sensation ◽

Heat Pulse ◽

Peltier Element ◽

Cold Pain ◽

Thermal Pulse ◽

Heat Sensation ◽

Thermal Stimulator ◽

Subjective Sensation ◽

Pulse Stimulation

AbstractAimsNovel quantitative thermal stimulator devices (QTSDs) have been developed to deliver thermal pulse stimulation with regulated constant temperatures (0–45°C) with a Peltier element probe (16 cm2). The aim of this study was to investigate subjective sensation induced by the interaction between simultaneously applied painful cold and heat stimuli in various sites.MethodsTwenty healthy subjects (12 men and 8 women, age range: 25–45 years) participated. The intensity of cold pain (CP) and heat pain (HP) stimuli were assessed by visual analogue scale (VAS) and adjusted to elicit approximately 70/100 mm. Alternately pulse stimulations (pulse duration of 40 s; 0.025 Hz) which consisted of CP, HP, or neutral temperature (32°C) were applied. Four conditions were tested and subjective sensations were assessed: (1) one QTSD was applied to non-dominant forearm and cold-heat pulse stimulation was applied.Two QTSDs were applied to (2) non-dominant ipsilateral forearm with 5 cm apart, (3) non-dominant and contralateral forearms, (4) non-dominant forearm and ipsilateral thigh, respectively. In conditions of (2)–(4), CP-neutral pulse stimulation (C-Neutral) and neutral-HP pulse stimulation (Neutral-H) were applied simultaneously with opposite phase, respectively.ResultsCP and HP were 3.9±1.0°C (mean±SD) and 43.6±0.9°C (mean±SD), respectively. The VAS values for CP and HP were 73.4±2.0 mm (mean±SD) and 76.4 ±4.8 mm (mean±SD), respectively. Some subjects could not discriminate cold or heat sensation and some felt cold as heat (paradoxical sensation). The number of subjects with such paradoxical sensation in (1), (2), (3), (4) were 9 (45%), 2 (10%), 0 (0%) and 3 (15%), respectively.ConclusionsIn healthy volunteers, simultaneous alternately cold-heat pulse stimulation on one site triggered paradoxical thermal sensation, which to a much less degree is triggered when C-Neutral and Neutral-H were applied to different dermatomes. This suggests that the mechanism is primarily triggered peripherally.

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Spectral Clustering Reveals Different Profiles of Central Sensitization in Women with Carpal Tunnel Syndrome

Symmetry ◽

10.3390/sym13061042 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1042

Author(s):

Oscar J. Pellicer-Valero ◽

José D. Martín-Guerrero ◽

César Fernández-de-las-Peñas ◽

Ana I. De-la-Llave-Rincón ◽

Jorge Rodríguez-Jiménez ◽

...

Keyword(s):

Carpal Tunnel Syndrome ◽

Clinical Features ◽

Carpal Tunnel ◽

Spectral Clustering ◽

Grip Force ◽

The Other ◽

Pressure Pain ◽

Thermal Pain ◽

Pressure Pain Thresholds ◽

Tunnel Syndrome

Identification of subgroups of patients with chronic pain provides meaningful insights into the characteristics of a specific population, helping to identify individuals at risk of chronification and to determine appropriate therapeutic strategies. This paper proposes the use of spectral clustering (SC) to distinguish subgroups (clusters) of individuals with carpal tunnel syndrome (CTS), making use of the obtained patient profiling to argue about potential management implications. SC is a powerful algorithm that builds a similarity graph among the data points (the patients), and tries to find the subsets of points that are strongly connected among themselves, but weakly connected to others. It was chosen due to its advantages with respect to other simpler clustering techniques, such as k-means, and the fact that it has been successfully applied to similar problems. Clinical (age, duration of symptoms, pain intensity, function, and symptom severity), psycho-physical (pressure pain thresholds—PPTs—over the three main nerve trunks of the upper extremity, cervical spine, carpal tunnel, and tibialis anterior), psychological (depressive levels), and motor (pinch tip grip force) variables were collected in 208 women with clinical/electromyographic diagnosis of CTS, whose symptoms usually started unilaterally but eventually evolved into bilateral symmetry. SC was used to identify clusters of patients without any previous assumptions, yielding three clusters. Patients in cluster 1 exhibited worse clinical features, higher widespread pressure pain hyperalgesia, higher depressive levels, and lower pinch tip grip force than the other two. Patients in cluster 2 showed higher generalized thermal pain hyperalgesia than the other two. Cluster 0 showed less hypersensitivity to pressure and thermal pain, less severe clinical features, and more normal motor output (tip grip force). The presence of subgroups of individuals with different altered nociceptive processing (one group being more sensitive to pressure pain and another group more sensitive to thermal pain) could lead to different therapeutic programs.

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F154. Machine learning for the analysis of single pulse stimulation in electrocorticography

Clinical Neurophysiology ◽

10.1016/j.clinph.2018.04.317 ◽

2018 ◽

Vol 129 ◽

pp. e125

Author(s):

Emile d’Angremont ◽

Geertjan J. Huiskamp ◽

Frans S. Leijten ◽

Christoph Brune ◽

Michel J. van Putten

Keyword(s):

Machine Learning ◽

Single Pulse ◽

Pulse Stimulation

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Inhibition of HDAC4 by GSK3β leads to downregulation of KLF5 and ASK1 and prevents the progression of intravertebral disc degeneration

Clinical Epigenetics ◽

10.1186/s13148-021-01005-9 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Lin Xiao ◽

Dongping Gong ◽

Loufeng Liang ◽

Anwei Liang ◽

Huaxin Liang ◽

...

Keyword(s):

Intervertebral Disc ◽

Disc Degeneration ◽

Cell Apoptosis ◽

Thermal Sensitivity ◽

Downstream Signaling ◽

Thermal Pain ◽

Histone Deacetylase 4 ◽

Staining Methods ◽

Hematoxylin And Eosin ◽

Safranin O

Abstract Background Intervertebral disc degeneration (IDD) is a major cause of lower back pain. This study aimed at exploring the effects of histone deacetylase 4 (HDAC4) and its upstream and downstream signaling molecules on IDD development. Methods A murine IDD model was established by inducing a needle puncture injury to the vertebrate, whereupon we isolated and transfected of nucleus pulposus (NP) cells. Disc height index (DHI) of the mice was determined by X-ray tomography, while the pain experienced by the IDD mice was evaluated by mechanical and thermal sensitivity tests. Next, the interaction between GSK3β and HDAC4 as well as that between HDAC4 and KLF5 acetylation was assessed by co-immunoprecipitation, while the promoter region binding was assessed identified by chromatin immunoprecipitation. By staining methods with TUNEL, Safranin O fast green, and hematoxylin and eosin, the NP cell apoptosis, degradation of extracellular matrix, and morphology of intervertebral disc tissues were measured. Furthermore, mRNA and protein expressions of GSK3β, HDAC4, KLF5, and ASK1, as well as the extent of HDAC4 phosphorylation, were determined by RT-qPCR and Western blotting. Results GSK3β was identified to be downregulated in the intervertebral disc tissues obtained from IDD mice, while HDAC4, KLF5, and ASK1 were upregulated. HDAC4 silencing alleviated IDD symptoms. It was also found that GSK3β promoted the phosphorylation of HDAC4 to increase its degradation, while HDAC4 promoted ASK1 expression through upregulating the expression of KLF5. In IDD mice, GSK3β overexpression resulted in increased DHI, inhibition of NP cell apoptosis, alleviation of disc degeneration, and promoted mechanical and thermal pain thresholds. However, HDAC4 overexpression reversed these effects by promoting ASK1 expression. Conclusion Based on the key findings of the current study, we conclude that GSK3β can promote degradation of HDAC4, which lead to an overall downregulation of the downstream KLF5/ASK1 axis, thereby alleviating the development of IDD.

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