Percepción del gusto como factor de riesgo para obesidad infantil / Taste perception as a risk factor for childhood obesity

Resumen Objetivo Describir el papel de la percepción del gusto como factor de riesgo para el desarrollo de obesidad en niños. Material y métodos Se realizó una búsqueda inicial de artículos científicos publicados en PubMed entre el 1 de enero de 2011 y el 20 de marzo de 2016 para el tema sobrepeso y obesidad en niños de entre 0 y 12 años. Los algoritmos utilizados fueron (Obesity OR Overweight) AND Taste perception, Satiation, Satiety response, Appetite, Appetite regulation, Habituation, Taste receptors [MeSH] y PROP phenotype. En búsquedas subsecuentes se incluyeron artículos previos y posteriores a la fecha de la búsqueda general (hasta mayo 2018). Resultados Las preferencias por los sabores inician desde la gestación, por lo que los niños que son expuestos a sabores dulces en etapas tempranas de la infancia aumentan su riesgo de habituación a éstos. Asimismo, las experiencias hedónicas dadas por la ingestión de alimentos y bebidas dulces refuerzan el consumo de estos alimentos, lo que propicia la selección de productos o bebidas de sabor dulce en etapas posteriores. Estas preferencias se han asociado con el desarrollo de obesidad en los niños. Las variantes genéticas relacionadas con la percepción del gusto también pueden contribuir a la selección de cierto tipo de alimentos. Sin embargo, su relación con una mayor ingestión de energía, así como con un mayor peso corporal, ha sido poco explorada y ha mostrado resultados inconsistentes. Conclusiones Se requiere más evidencia para entender las interacciones ambientales y genéticas de la percepción del gusto, a fin de considerarlo un factor más en las intervenciones de política pública.

Abstract Objective To describe the role of taste perception in the development of sweet taste habituation as well as its relationship to the development of obesity in children. Materials and methods An initial search of scientific articles published in PubMed between January 1st, 2011 and March 20th, 2016 was performed in children between 0 and 12 years old. The algorithms used were (Obesity OR Overweight) AND (Taste perception, Satiation, Satiety response, Appetite, Appetite regulation Habituation, Taste receptors [MeSH]) and PROP phenotype. Subsequent searches included papers published before and after date of initial search (until May 2018). Results Flavor preferences start as early as taste system development during pregnancy. Therefore, children who are exposed to sweet flavors in early childhood, increase their risk of habituation to them. Likewise, the hedonic experiences given by the ingestion of sweet foods and beverages, reinforce the consumption of these foods, perpetuating their selection in later stages. Preference for sweet taste has been associated with the development of obesity in children. Functional genetic variants related to taste perception can also contribute to the selection of certain types of foods and there is enough evidence that supports this idea. However, its contribution to a higher energy intake as well as a higher body weight has been poorly explored with inconsistent results. Conclusions More evidence is required to understand the environmental and genetic interactions of taste perception, so in turn, it can be consider as a key factor for preventing child obesity.

La fisiología vista desde un sistema nervioso autónomo ampliado y circadianamente organizado Bases para un enfoque Bio-Psico-Social-Ecológico de la salud y la enfermedad / THE PHYSIOLOGY OBSERVED SINCE AN AMPLIED AND CIRCADIANILLY ORGANIZED AUTONOMIC NERVOUS SYSTEM. BASIS FOR A BIO-PSICHO-SOCIAL-ECOLOGICAL APPROACH DURING HEALTH AND DISEASE

El sistema nervioso autónomo (SNA) es un componente fundamental del sistema nervioso cuya función es mantener la homeostasis y reaccionar de forma adaptativa a los cambios en el medio externo e interno. Participa en la regulación de la respiración, la circulación, la digestión, el metabolismo y el medio interno, la secreción exocrina y endocrina, las respuestas inmunes, la temperatura corporal y la reproducción. En este trabajo se analizará cómo la organización del SNA se construye en 4 niveles jerárquicos, a partir de un periodo de diferenciación crítico neonatal en el cual el medio ambiente y el vínculo afectivo con la madre juega un rol predominante. A continuación, se discutirá cómo la función del SNA cambia en las tres configuraciones corporales (vigilia, sueño de ondas lentas, sueño de movimientos oculares rápidos, REM) que se suceden durante un ciclo de 24 horas. Por último, se discutirá la aplicación de estos conceptos en la Unidad Neurofisiología del Curso de Fisiología para alumnos de 2º año de la Facultad de Ciencias Médicas, UCA, enfatizando los aspectos instrumentales destinados a aumentar la participación de los alumnos en el proceso de enseñanza

The autonomic nervous system (ANS) is a fundamental component of the nervous system whose function is to maintain homeostasis and react adaptively to changes in the external and internal environment. It participates in the regulation of respiration, circulation, digestion, metabolism and internal environment, exocrine and endocrine secretion, immune response, body temperature and reproduction. In this review article I will analyze how the organization of the ANS is built on 4 hierarchical levels, starting from a period of critical neonatal differentiation in which the environment and the affective bond with the mother plays a predominant role. Next, I will discuss how the ANS function changes in the three body configurations (wakefulness, slow wave sleep, fast eye movement, REM) that occur during a 24 hour cycle. Finally, the application of these concepts to teaching Neurophysiology at the Physiology Course for 2nd year medical students of the Faculty of Medical Sciences, Pontificia Universidad Católica Argentina, emphasizing the instrumental aspects intended to increase the participation of students in the teaching process is discussed.

Relações filogenéticas dos tubarões-martelo (Elasmobranchii: Sphyrnidae) com ênfase em morfologia / Phylogenetic relationships of hammerhead sharks (Elasmobranchii: Sphyrnidae) with emphasis on morphology

A cabeça lateralmente expandida é a principal sinapomorfia da família Sphyrnidae, a qual compreende todos os tubarões-martelo. Apesar de haver trabalhos abordando esta família, sua anatomia interna tem sido negligenciada como fonte de caracteres para serem utilizados na taxonomia e filogenia dos Sphyrnidae, em especial acerca de seu cefalofólio. Além disso, outros caracteres permanecem pouco estudados na família, tais como os referentes à anatomia dentária, dentículos dérmicos e sistema de poros sensoriais do cefalofólio. As relações filogenéticas entre os Sphyrnidae, e desta família entre os demais Carcharhiniformes, ainda é controversa como sua taxonomia. As poucas hipóteses filogenéticas conhecidas, baseadas em morfologia, não foram testadas sob critérios sistemáticos. Já as poucas hipóteses moleculares existentes foram testadas mas são ainda mais controversas. O presente estudo apresenta uma revisão anatômica e taxonômica dos Sphyrnidae, construindo uma matriz de caracteres mais robusta para testar as relações filogenéticas entre os Sphyrnidae, contando com 3 gêneros relacionados no grupo externo: Carcharhinus, Rhizoprionodon e Negaprion. Os resultados posicionam S. tiburo na base da família, e E. blochii e S. tudes compondo um dos clados mais derivados. Espécies de maior porte e cefalofólio mais expandido compõem um clado formado por S. mokarran + (S. lewini + S. zygaena), ao paso que as de menor porte e com cefalofolio mais arredondado formam um grupo polifilético. Rhizoprionodon acutus aparece como monofilético à família Sphyrnidae quando incluído fora do grupo externo. As árvores de consenso (Strictus, Semistrictus, Majority-rule e Adams) apresentam os mesmos resultados. Os caracteres cranianos, sensoriais e de dentículo dérmico são os que mais suportaram os diversos clados. Após a revisão taxonômica da família, a filogenia com base em morfologia apresentou-se mais consistente e clara, embora controversa aos dados moleculares.

The laterally expanded head is the main synapomorphy of the family Sphyrnidae, which comprises all the hammerhead sharks. In spite of the existence of some works on this family, the internal anatomy have been neglected as a soured of characters to be used in the taxonomy and phylogeny of this family, especially about the cephalofoil. Additionally, other characters remains poorly studied in Sphyrnidae, such as the complete teeth anatomy, dermal denticles and sensorial system of pores in the cephalofoil. It is advocated here that the study of such sources of features would give new characters to construct a more robust matrix to be used in the phylogeny of this family. The interrelationships within the Sphyrnidae, as well as of this family among the other Carcharhiniformes is still controversial as their taxonomy. The few phylogenetical hypothesis based on morphology were never tested before, besides acceptted by many authors. In the other hand, the few hypothesis based on molecular data were tested but are even more controversial. The present study presents a anatomic and taxonomic review of the family Sphyrnidae, constructing a more robust matrix that were tested to verify the interrelationships within the family Sphyrnidae, using, for the first time, 3 related genera: Carcharhinus, Rhizoprionodon and Negaprion. The results show that S. tiburo is the most basal living sphyrnid, and E. blochii and S. tudes comprise one of the most derived clade. The large species with the most expanded cephalofoil comprise a monophyletic clade S. mokarran + (S. lewini + S. zygaena), while the small sized species with a more rounded cephalofoil are a polifiletic group. Rhizoprionodon acutus appeared as monophyletic to Sphyrnidae when included ouside the outgroup. The consensus trees (Strictus, Semi-strictus, Majority-rule and Adams showed the same relashionships. The cranial characters supported many clades, followed by sensorial and dermal denticle features...

Nidogen Plays a Role in the Regenerative Axon Growth of Adult Sensory Neurons Through Schwann Cells

We previously reported that nidogen is an extracellular matrix protein regulating Schwann cell proliferation and migration. Since Schwann cells play a critical role in peripheral nerve regeneration, nidogen may play a role in it via regulation of Schwann cells. Here, we demonstrate direct evidence that nidogen induces elongation of regenerative axon growth of adult sensory neurons, and that the effect is Schwann cell dependent. Continuous infusion of recombinant ectodomain of tumor endothelial marker 7, which specifically blocks nidogen function in Schwann cells, suppressed regenerative neurite growth in a sciatic nerve axotomy model. Taken together, it is likely that nidogen is required for proper regeneration of peripheral nerves after injury.

Sensory nerve conduction velocity is greater in left handed persons.

Dependence of nerve conduction velocity on factors like age, sex and temperature is well known. Effect of handedness on nerve conduction velocity has not been studied adequately. In this study correlation between handedness and motor as well as sensory conduction velocity of right as well as left median nerve was studied in 84 medical students in the age group between 17-21 years out of which 72 were right handed and 12 were left handed. In addition auditory and visual reaction times were also studied. Sensory conduction velocity in both right and left median nerve was significantly higher in left handers as compared with right handers whereas, the motor conduction velocity in right handers and left handers was not different. The auditory and visual reaction times were also not different in these groups. Because of greater sensory conduction velocity in left handers there is a requirement of different set of normal reference values for left handers in clinical diagnosis.

Left ventricular dysfunction and extravascular fluid in the lung: physiological basis for symptoms.

The essential feature of left ventricular dysfunction is an increase in left atrial pressure and pulmonary venous congestion leading to a fluid flux across the pulmonary microvasculature. Small acute increases (< 10 mmHg) in left atrial pressure enhance the extravascular fluid volume in the airways and activate the rapidly adapting receptors (RAR). With larger increases in left atrial pressure (approximately 25 mmHg) both the RAR and the C-fiber receptors in the airways and the alveoli are activated. Activation of RAR causes a reflex increase in respiratory rate, tracheal tone and mucus secretion from the airways. It appears that small increases in extravascular fluid volume of the airways also cause a reflex diuresis which is mediated by activation of neuronal nitric oxide synthase in the renal medulla. In contrast, when left atrial pressure is elevated chronically, further small increments in extravascular fluid volume of the airways no longer stimulate the RAR. The reflex diuresis is also not evident under these circumstances. However, the RAR continue to be activated by increments in left atrial pressure in excess of 25 mmHg. It is suggested that the RAR of the airways play a significant role in monitoring changes in the extravascular fluid volume of the airways and mediate the reflexes which are associated with the symptomatology of acute left ventricular dysfunction.

Airway rapidly adapting receptors--sensors of pulmonary extra-vascular fluid volume.

The factors regulating transfer of fluid into the pulmonary extra-vascular space and the role of sensory receptors of the airways in detecting such fluid fluxes are reviewed and discussed. It is concluded that the rapidly adapting receptors (RARs) located in apposition to bronchial venules are highly sensitive to changes in the pulmonary extra-vascular space produced by mild elevations of left atrial pressure, plasmapheresis and pulmonary lymphatic obstruction and their activation causes respiratory stimulation, an increase in tracheal tone and cough. There is a reflex diuresis also following the stimulation of these receptors by pulmonary lymphatic obstruction. It is proposed that the RARs function as a sensory component of the pulmonary defence mechanisms which preserve the 'milieu interior'.

Morphological observations of the sensory nerve endings of the Calomys callosus' lingual mucosa, employing the silver impregnation method

Estudaram-se as características morfológicas das terminaçöes nervosas sensitivas da mucosa lingual de Calomys callosus, empregando-se a técnica de impregnaçäo pela prata. Para a obtençäo das peças, cada animal foi anestesiado com injeçäo intraperitonial de tionembutal sódico. As peças foram fixadas em soluçäo de formalina a 10 por cento por um período de 20 dias à temperatura ambiente e cortes espessos de 40-60 micrometros foram obtidos em criostato Linde. As preparaçöes foram coradas pela técnica de impregnaçäo pela prata. De acordo com os nossos resultados podemos concluir que: 1) todas as regiöes (anterior, média e posterior) da mucosa dorsal da língua de Calomys callosus possuem terminaçöes nervosas sensitivas; 2) as terminaçöes nervosas podem ser simples ou complexas localizando-se no tecido conjuntivo da lâmina própria ou no interior das papilas conjuntivas das papilas filiformes, fungiformes e valadas, 3) as terminaçöes nervosas livres no interior das papilas fungiformes dispöem-se longitudinalmente ou formando uma rede complexa de fibras nervosas terminais

Substrato anatômico da sensibilidade tátil na hanseníase / anatomic substratum of tactile sensibility in hanseniasis

Proposta de uma melhor avaliaçäo, com bases anatômicas e métodos clínicos de fácil execuçäo, da sensibilidade tátil na hanseníase

Consideraçöes sobre as relaçöes neurais e etológicas na avaliaçäo das alteraçöes do controle motor. I. Substratos neurais da motricidade / Neural and ethological relations in the evaluation of motor control changes. I. Neural substrates of motricity

O movimento é a expressäo final da ativaçäo harmônica de múltiplos sistemas cerebrais e musculares. Na natureza ele medeia respostas primárias de profundo valor adaptativo como a reproduçäo, predaçäo e fuga entre outras. A descripçäo dos movimentos como atos ou padröes motores correspondeu inicialmente à Etologia. Com o avanço nas Neurociências, hoje é proposta abordagem neuretológica para a pesquisa nesta área. Quando se apresentam disfunçöes do movimento, praticamente os mesmos sistemas musculares e cerebrais säo utlizados, só que de maneira aberrante, tanto no tempo quanto no espaço. Nesta revisäo säo ilustrados os principais sistemas envolvidos no controle motor normal, particularmente córtex, gânglios, cerebelo, tronco cerebral, medula, periferia muscular receptora e efetora

The Physiological Significance of Natural Mechanical Stimulus in the Field of Cerebrospinal Nervous System

Full evidence and obvious reasons made it possible to arrive at the conclusion that the nature of transmission upon cerebrospinal neurons is overwhelmingly mechanical, not only in the periphery- between various receptors and afferent nerve terminals, and between surrounding tissues and free nerve endings- but also in the cerebral cortex. When viewed from the standpoint of the everchanging patterns of natural mechanical stimuli, the neurons in the conscious cerebral cortex and the pain endings in an acute inflammatory locus have the same situation very much in common. It is quite likely that natural mechanical stimuli dominate over cerebrospinal nervous phenomena and physiologists have been watching the missing mechanism at work in every experiment upon afferent nerve terminals and cerebral cortex that they have done. The terms "psychic tension" and "central excitatory state" comparable to muscular tonus are of interest because they involve the use of mathematical techniques in psychology and neurophysiology. They are capable of becoming weak or strong, and they serve as an inner stimulus to give impetus to behavior. Unfortunately, however, it is an elusive inner stimulus, and it defies a lucid definition. But natural mechanical stimuli embody the psychic tension and the central excitatory state ultimately. It seems now that we just found a place where constant complaints against neurophysiology and physiological psychology are ventilated. We may conclude that natural mechanical stimuli are the leading direct stimuli to cerebrospinal neurons in the human body, and the plastic and developmental nervous phenomena and mental phenomena can be explained objectively by a familliar datum of mechanical energy and that we can reasonably expect the day of regarding material world and spiritual world in the monistic conception of matter-energy system.