A pele que somos e a pele que sentimos: Pele - símbolo - consciência / The skin we are, the skin we feel: Skin - symbol - consciousness / La piel que somos y la piel que sentimos: Piel - símbolo - conciencia

O sistema somatosensorial humano funciona de forma dinâmica. Nossos órgãos recebem e produzem estímulos que são convertidos em informação biológica, necessária para a formação, maturação e funcionamento global do nosso corpo, mente e espírito. O "sentir-se bem, sentir-se com saúde" é uma consequência de vários fenômenos biológicos que envolvem o sistema nervoso central. Neste contexto, serão abordados os papéis da pele, do tato e do toque no desenvolvimento e estruturação da consciência e do que se chama "pele simbólica" ou "pele psíquica".

The human somatosensory system works in a dynamic way. Our organs receive and produce stimuli that will be converted into biological information, which are necessary for formation, maturation and the overall functioning of the body, mind, and spirit. The "wellbeing sensation" is a result of several biological phenomena that involve the central nervous system. In this context, the role of skin, tact and touch in the development and structuring of our consciousness will be discussed. The concepts of "symbolic skin" and "psychic skin" will be explored.

El sistema somatosensorial humano funciona de forma dinámica. Nuestros órganos reciben y producen estímulos que se convierten en información biológica, necesaria para la formación, maduración y funcionamiento global de nuestro cuerpo, mente y espíritu. El "sentirse bien, sentirse con salud" es una consecuencia de varios fenómenos biológicos que involucran el sistema nervioso central. En este contexto, se abordarán el papel de la piel, del tacto y del toque en el desarrollo y estructuración de la conciencia y de lo que se llama "piel simbólica" o "piel psíquica".

Activation of C-fiber nociceptors by low-power diode laser / Ativação por laser de diodo de baixa potência de nociceptores relacionados a fibras C

ABSTRACT Objective The evaluation of selective activation of C-fibers to record evoked potentials using the association of low-power diode laser (810 nm), tiny-area stimulation and skin-blackening. Method Laser-evoked potentials (LEPs) were obtained from 20 healthy young subjects. An aluminum plate with one thin hole was attached to the laser probe to provide tiny-area stimulation of the hand dorsum and the stimulated area was covered with black ink. Results The mean intensity used for eliciting the ultra-late laser-evoked potential (ULEP) was 70 ± 32 mW. All subjects showed a clear biphasic potential that comprised a negative peak (806 ± 61 ms) and a positive deflection (1033 ± 60 ms), corresponding to the ULEP related to C-fiber activation. Conclusion C-fiber-evoked responses can be obtained using a very low-power diode laser when stimulation is applied to tiny areas of darkened skin. This strategy offers a non-invasive and easy methodology that minimizes damage to the tissue.

RESUMO Objetivo Avaliação da ativação de fibras C para o registro de potenciais evocados utilizando-se laser de baixa potência, áreas pequenas de estimulação e escurecimento da pele. Método Potenciais evocados foram obtidos de 20 sujeitos. Uma placa de alumínio com uma pequena abertura foi acoplada à ponteira do laser para estimular área escurecida do dorso da mão. Resultados A intensidade média utilizada para estimulação foi de 70 ± 32 mW. Todos os sujeitos apresentaram respostas claras compreendendo dois picos um negativo (806 ± 61 ms) seguido por outro positivo (1033 ± 60 ms), correspondendo ao potencial evocado tardio por estimulação de fibras C. Conclusão Respostas de fibras C podem ser obtidas utilizando-se laser de baixa potência quando a estimulação é aplicada a pequenas áreas de pele escurecida. Esta estratégia oferece uma metodologia não invasiva que minimiza danos teciduais.

Descripción de las propiedades funcionales del sistema nociceptivo trigeminal en relación con el dolor pulpar / Description of the functional properties of the nociceptive trigeminal system in relation to pulpal pain

El sistema trigeminal nociceptivo es un componente del sistema sensorial somestésico que tiene la capacidad de discriminar cuatro variables básicas de los estímulos que provocan daño tisular, ellas son: cualidad, curso temporal, localización e intensidad. Las fibras A delta y C, vinculadas a la nocicepción están presentes en la pulpa dental. Se utilizan varias clasificaciones del dolor, atendiendo a diversos criterios: calidad de la sensación, velocidad de transmisión por las fibras, en relación con el lugar del cuerpo donde se exprese, y a la ubicación del nociceptor. La evolución de las condiciones pulpares se clasifican como: pulpitis reversible, pulpitis transicional, pulpitis irreversible y pulpa necrótica.Según su cualidad, el dolor pulpar puede ser punzante o continuo; atendiendo a su aparición, provocado o espontáneo; por su curso, intermitente o continuo; por su localización puede ser limitado a una región, irradiado y referido; y en relación con su intensidad se considera leve, moderado o severo. La capacidad del sistema sensorial nociceptivo en cuanto a discriminar la modalidad, curso temporal, localización e intensidad del estímulo, permite conocer las diferentes etapas de un proceso inflamatorio pulpar(AU)

The nociceptive trigeminal system is a component of the somatosensory system capable of distinguishing four basic variables of stimuli causing tissue damage: quality, time course, location and intensity. A-delta and C fibers, which are related to nociception, are present in dental pulp. Several classifications of pain are used, based on various criteria: quality of the sensation, transmission velocity along fibers, body part where it is expressed, and location of the nociceptor. According to their evolution, pulpal conditions are classified into reversible pulpitis, transitional pulpitis, irreversible pulpitis and necrotic pulp. Pulpal pain has been classified according to the following variables: quality: sharp or continuous; cause: provoked or spontaneous; course: intermittent or continuous; location: limited to a region, radiating or referred; and intensity: mild, moderate or severe. The capacity of the nociceptive sensory system to distinguish the mode, time course, location and intensity of the stimulus makes it possible to recognize the different stages of a pulpal inflammatory process(AU)

Human Cutaneous Nociceptive Afferents with Unmyelinated (C), and myelinated (Aδ) fibers / 全日本鍼灸学会雑誌

Inserting a tangusten microelectrode into the peroneous nerve of the conscious human subject, the authors recorded the discharge of primary afferent C and A δ fibers. Most of the C fibers belonged to the polymodal group, as these were excited by both mechanical and thermal stimulations. These units responded to painful mechanical or thermal stimuli, as well as to non-painful stimuli of these modalities. These polymodal receptors were capable of responding to a wide range of stimulation intensity.<br>Only some of the Aδ fibers responded to mechanical stimulation of a high intensity and painful thermal stimulation. These units increased their discharge to repeated heat administration showing a marked sensitization. This sensitization corresponded to the sense of increased heat experience by the human subjects who had hyperalgesia from the increasing heat. These findings indicate that these Aδ afferent fibers transmit sensation of hyperalgesia from the hairy skin to the higher centers.