Research progress on clinical manifestations and mechanism of radiation-induced taste dysfunction in head and neck cancers / 中华放射肿瘤学杂志

Taste is a critical sensory function for human as it supports sustenance and alerts the body to toxins. Taste dysfunction is a common side effect of radiotherapy for the head and neck cancers, which is often accompanied by oral mucositis in the early stage. It is associated with anorexia, anxiety and depression, leading to declined quality of life and treatment tolerance. The incidence of radiation-induced taste dysfunction is high, and its clinical manifestations include increased taste threshold, tastelessness, and persistent bitter, sour or metallic taste, which exert significant effect upon the quality of life. At present, effective therapeutic measures for radiation-induced taste dysfunction are still lacking. In this article, research progresses on clinical characteristics and the potential mechanisms of radiation-induced taste dysfunction were reviewed, aiming to provide reference for the mechanism, prevention and treatment for taste dysfunction.

Taste perception in complete denture wearers / Percepção do sabor em usuários de prótese dentária total

ABSTRACT Purpose: to assess the recognition of salty, sweet, and citrus tastes in complete denture wearers. Methods: the study included toothless individuals (experimental group) who had been using, for at least 3 months and at the most 5 years, acrylic resin removable bimaxillary complete dentures in good condition and with adequate maxillo-mandibular relationship. The same assessment was performed in the control group, which had 26 toothed individuals. Volunteers had no difficulties ingesting any type of food. Salty, sweet, and citrus tastes were assessed with filter paper strips soaked in such solutions and placed on the tongue dorsum. Assessments were performed in duplicate and in random order. Results: the percentage rate of errors was similar between the control (9.6±13.5%) and experimental groups (10.5±15.5%) (p=0.80). There was no difference in the frequency of correct perception of tastes between denture wearers and toothed individuals. Conclusion: individuals who wore acrylic resin removable bimaxillary complete dentures perceived salty, sweet, and citrus tastes like toothed individuals did.

RESUMO Objetivo: avaliar o reconhecimento dos sabores salgado, doce e cítrico em usuários de prótese dentária total. Métodos: foram incluídos indivíduos desdentados (grupo experimental) usuários de prótese total removível bimaxilar confeccionada em resina acrílica, com tempo mínimo de uso de três meses e máximo de cinco anos, em bom estado de conservação e com adequada relação maxilo-mandibular. Como grupo controle, a mesma avaliação foi realizada em 26 indivíduos dentados. Os voluntários não tinham dificuldade na ingestão de nenhum tipo de alimento. Os sabores salgado, doce e cítrico foram testados com fitas de papel filtro embebidas nas soluções e colocadas na parte dorsal da língua. As avaliações foram realizadas em duplicata e em ordem ao acaso. Resultados: a taxa percentual de erros foi igual entre os grupos controle (9,6±13,5%) e experimental (10,5±15,5%) (p=0,80). Não houve diferenças na frequência de percepção correta dos sabores entre indivíduos usuários de prótese e indivíduos dentados. Conclusão: usuários de prótese total removível bimaxilar confeccionada em resina acrílica têm a mesma percepção dos sabores salgado, doce e cítrico que indivíduos dentados.

Colgajo con preservación de papilas en defecto óseo del sector anterior / Papilla-preserving flap in bone defect of the anterior sector

RESUMEN La técnica de preservación de papilas en el tratamiento de las periodontitis ofrece ventajas en cuanto a la protección del sitio del defecto cuando en este se pretende realizar cirugía ósea aditiva. La combinación de este proceder con la regeneración tisular guiada garantiza mayor protección a la membrana colocada con este fin. Se presenta el caso de un paciente de 47 años de edad, masculino, cibernético de profesión, que recibió tratamiento periodontal pero no acudió a su fase de mantenimiento y en este momento lo hace por presentar movilidad y sangrado gingival manifestado fundamentalmente al realizar los procedimientos de higiene bucal. Se le realizó un colgajo con preservación de papilas, entre los incisivos centrales superiores, colocándole un injerto de Bio-Oss y una membrana de colágeno, con lo que se obtuvo una mayor altura del hueso y una disminución de la profundidad de la bolsa.

ABSTRACT The papillae preservation technique in the treatment of periodontitis offers advantages in terms of protecting the defect site when additive bone surgery is intended to be performed on it. The combination of this procedure with guided tissue regeneration guarantees greater protection for the membrane placed for this purpose. We present a 47-year-old male patient, computer engineer as a profession, who received periodontal treatment but did not attend his maintenance phase; he does so due to mobility and gingival bleeding manifested mainly when performing oral hygiene procedures. A papilla-preserving flap was made between the upper central incisors, placing a Bio-Oss graft and a collagen membrane, which resulted in greater bone height and decreased pocket depth.

Development and homeostasis of taste buds in mammals / 华西口腔医学杂志

Taste is mediated by multicellular taste buds distributed throughout the oral and pharyngeal cavities. The taste buds can detect five basic tastes: sour, sweet, bitter, salty and umami, allowing mammals to select nutritious foods and avoid the ingestion of toxic and rotten foods. Once developed, the taste buds undergo continuous renewal throughout the adult life. In the past decade, significant progress has been achived in delineating the cellular and molecular mechanisms governing taste buds development and homeostasis. With this knowledges and in-depth investigations in the future, we can achieve the precise management of taste dysfunctions such as dysgeusia and ageusia.

Alteration of taste buds in experimental cirrhosis. Is there correlation with human hypogeusia? / Alteração de paladar em um modelo experimental de cirrose. Existe correlação com hipogeusia humana?

ABSTRACT Background The inherent complications of cirrhosis include protein-calorie malnutrition and micronutrient deficiencies.Changes in taste are detrimental to the nutritional status, and the mechanism to explain these changes is not well documented in the cirrhotic patients. Objective To evaluate the taste buds of cirrhotic rats. Methods Fourteen male Wistar rats were evaluated. After 16 weeks, the liver was removed to histologically diagnose cirrhosis, and blood was collected to perform liver integrity tests. The tongue was removed for histological examination and immunohistochemistry using antibodies against protein gene product PGP 9.5 and the sweet taste receptors T1R2 and T1R3. Morphological changes were determined by scanning electron microscopy. Serum zinc levels were measured. Results The cirrhotic animals, but not the control animals, exhibited zinc deficiency. In both groups, there was positive immunoreactivity for type II and III cells and T1R2 receptors. The cirrhotic animals had no immunoreactivity for T1R3 receptors. Scanning electron microscopy analysis of the cirrhotic group revealed a uniform tapering of the gustatory papillae. Conclusion In conclusion the experimental cirrhosis model mimicked the biochemical and histological parameters of human cirrhosis, therefore enabling a study of the gustatory papillae and taste buds.

RESUMO Contexto As complicações inerentes de cirrose incluem a desnutrição proteico-calórica e deficiências de micronutrientes. Alterações no paladar são prejudiciais para o estado nutricional e o mecanismo para explicar essas mudanças não é bem documentada nos pacientes cirróticos. Objetivo Avaliar as papilas gustativas de ratos cirróticos. Métodos Foram avaliados 14 ratos Wistar machos. Após 16 semanas, o fígado foi removido para diagnosticar histologicamente cirrose, e o sangue foi colhido para efetuar testes de integridade hepática. A língua foi removida para exame histológico e imuno-histoquímica utilizando anticorpos contra o gene da proteína PGP 9.5 e os receptores de sabor doce T1R2 e T1R3. As alterações morfológicas foram determinadas por microscopia eletrônica de varredura e os níveis de zinco no soro foram medidos. Resultados Os animais cirróticos, em relação aos animais controle, apresentaram deficiência de zinco significativa. Em ambos os grupos, houve imunorreatividade positiva para o tipo II e células III e receptores T1R2. Os animais cirróticos não tinham imunoreactividade para receptores T1R3. Microscopia eletrônica de varredura do grupo cirrótico revelou um afilamento uniforme das papilas gustativas. Conclusão O modelo de cirrose experimental imitou os parâmetros bioquímicos e histológicos de cirrose humana, portanto, permitindo um estudo das papilas gustativas e paladar.

Papel de la leptina en la fisiología y fisiopatología oral / Leptin’s role in oral physiology and physiopathology

Hace 20 años se caracterizó por primera vez a la leptina, como un péptido anorexigénico que actúa a nivel del hipotálamo y desde entonces se le ha descrito un papel clave en el funcionamiento de una gran diversidad de tejidos, siendo la boca un sitio blanco para muchas funciones mediadas por este péptido, tales como la inducción del crecimiento y diferenciación de diversos tejidos dentales y periodontales, la modulación de la percepción del sabor dulce en las papilas gustativas, la regulación de la deglución y la activación de la respuesta inmunológica. Por otra parte, la leptina juega un papel importante en la mediación de la respuesta ante diferentes agentes agresores en la boca, como las bacterias periodontopatógenas y el alcohol, además participa en ciertos tipos de cáncer en esta cavidad. Este resumen pretende dar una visión general de los diferentes roles que cumple la leptina a nivel bucal descritos hasta la fecha, comenzando por su función en la boca sana, hasta llegar a su participación en la fisiopatología bucal.

Leptin was characterized for the first time 20 years ago as an anorexigenic peptide that acts on the hypothalamus and has since been described as having a key role in the functioning of a great number of tissues. The mouth is one of the areas of the body where this peptide influences processes, such as growth induction and differentiation of various dental and periodontal tissues, modulation of sweet tastes’ perception in the taste buds, swallowing regulation and immune response activation. Moreover, leptin also plays an important role in mediating the response to different oral aggressors, such as periodontopathic bacteria and alcohol, as well as its involvement in certain types of mouth cancer. This review aims to provide an overview of leptin’s known roles on the oral cavity to date, ranging from its function in a healthy mouth to its involvement in oral physiopathology.

Percepção de sabores em pessoas normais / Flavor perception in healthy volunteers

Introdução: percepção do sabor do alimento ingerido pode ter importante papel na proteção do sistema digestivo. Objetivo: avaliar a capacidade de percepção dos sabores amargo, azedo, doce e neutro em pessoas normais. Método: foram estudados 46 indivíduos saudáveis, 22 homens e 24 mulheres com idades entre 23 e 71 anos, média de 45 anos. Cada sujeito deglutiu, em sequência aleatória, 5 mL de bolos líquidos com 4 sabores: amargo (chá de Peumus boldus), azedo (suco de limão diluído), doce (sacarose diluída) e neutro (água) na temperatura ambiente. Após cada deglutição, os participantes foram questionados sobre o sabor do líquido deglutido. Resultados: não houve diferença na frequência de acertos na identificação dos sabores (amargo: 80%, azedo: 85%, neutro: 89% e doce: 89%). Não houve diferenças relacionadas ao gênero na identificação dos sabores. Cinco indivíduos (25%) entre os jovens (23-39 anos) não identificaram o sabor azedo, o que aconteceu em 2 (8%) dos mais idosos (40-71 anos). Vinte e sete (59%) indivíduos identificaram todos os sabores, 13 (28%) não identificaram um sabor, 5 (11%) não identificaram dois sabores e um indivíduo (2%) não identificou 3 sabores. Conclusão: entre 80% e 90% dos sujeitos da população estudada foram capazes de identificar o gosto do líquido que deglutiu, mas 41% não identificou pelo menos um sabor entre os quatro avaliados.

Introduction: perception of the swallowed bolus taste may have an important role in the protection of the digestive tract. Objective: to evaluate the perception of bitter, sour, sweet and neutral tastes of a liquid bolus in normal individuals. Method: we studied 46 healthy subjects, 22 men and 24 women aged 23 to 71 years, mean 45 years. Each subject swallowed in a random sequence, 5 mL of a liquid bolus with four flavors: bitter (Peumus Boldus tea), sour (limon juice diluted), sweet (sucrose diluted) and neutral (water) all at room temperature. After each swallow the participants were asked about the taste of the liquid swallowed. Results: there was no difference in the frequency of the correct identification of flavors (bitter: 80%, sour: 85%, neutral: 89% and sweet: 89%). There was no gender difference in the flavor identification. Five (25%) of the younger subjects (20-39 years) did not identify the sour taste, what happen in 2 (8%) of older subjects (40-71 years). Twenty-seven (59%) individuals identified all flavors, 13 (28%) did not identify one flavor, 5 (11%) did not identify two flavors and only one individual (2%) did not identify three flavors. Conclusion: between 80% to 90% of the population studied was able to identify the taste of the liquid they swallowed, but 41% did not identify at least one flavor.

Células neuroendocrinas en yemas gustativas primordiales / Neuroendocrine cells in primordial taste buds

El objetivo del trabajo fue identificar la presencia de células neuroendócrinas en yemas gustativas primordiales (fetales) humanas. Fueron utilizadas 15 lenguas fetales humanas obtenidas de abortos espontáneos (tiempo de gestación 23 semanas) de pacientes ingresados en el Hospital General, Chihuahua, México. Una muestra representativa del ápex lingual fue embebida en parafina y cortada a 3 micras para ser procesadas con la técnica inmunohitoquímica utilizando los siguientes anticuerpos: Anti-sinaptofisina; anti-proteína neurofilamento; anti-cromogranina; anti-citoqueratina 20; y anti proteínas-S100. El protocolo de investigación fue aprobado por los comités de bioética de las instituciones participantes. Se obtuvo la autorización de los padres para la utilización del material biológico. Las células gustativas fetales fueron fuertemente positivas a cromogranina, y negativas a sinaptofisina. Las papilas gustativas fetales humanas mostraron inmunorreactividad positiva contra citoqueratina 20, mientras que fibras nerviosas intragemulares mostraron inmunorreactividad contra anticuerpos anti-proteína neurofilamento. Las fibras nerviosas subyacentes al epitelio gustativo fueron positivas a proteína S100. Se muestra evidencia inmunohistoquímica de la presencia de células neuroendócrinas gustativa en yemas gustativas linguales primordiales humanas. Esto sugiere una probable participación neuroendocrina o paracrina en el desarrollo de las yemas gustativas humanas.

The objective was to identify the presence of neuroendocrine cells in primary taste buds (fetal) cells. We used 15 human embryionic fetal tongues derived from human spontaneous abortions (23 weeks gestation time) of patients admitted to the General Hospital, Chihuahua Mexico. A representative sample of lingual apex was embedded in paraffin and cut to 3 microns processed by immune histochemical technique using the following antibodies: anti-synaptophysin, neuro filament anti-protein, anti chromogranin; anti-citokeratin 20 and S100 anti proteins. Research was approved by bioethics committees of the participating institutions. Permission was obtained from the parents to use the biological material. The taste bud fetal cells were significantly positive for chromogranin and synaptophysin negative. The human fetal taste buds showed positive immunoreactivity against cyto keratin 20, while nerve fibers underlying the gustatory epithelium were positive for S100 protein. Immunohistochemical evidence shows the presence of neuro endocrine cells in human primordial taste bud papilla. This suggests a probable neuro endocrine or paracrine participation in the development of human taste buds.

Sensopercepción gustativa: una revisión / Gustatory sensory perception: a review

Los órganos de los sentidos confieren a los seres humanos la capacidad de percibir y responder a una gran gama de estímulos que provienen del entorno, lo cual nos brinda la facultad de elaborar respuestas con el fin de adaptarnos a los cambios medioambientales, cubrir nuestras necesidades básicas y sobrevivir. Para nutrirnos, el sentido del gusto posee un rol primordial que nos permite seleccionar dentro de una amplia variedad de alimentos, las sustancias que son necesarias para nuestro metabolismo, protegiéndonos a su vez de compuestos potencialmente nocivos, debido a su toxicidad o grado de descomposición. Este sentido también es capaz de brindarnos la capacidad de seleccionar y discriminar alimentos que nos permitan sentir agrado y placer. Para los dentistas es fundamental comprender adecuadamente los complejos procesos del sentido del Gusto, identificar las estructuras involucradas tanto a nivel periférico (papilas, receptores y vías nerviosas) como a nivel central (núcleos y cortezas cerebrales); además de conocer las modalidades básicas del gusto y sus respectivos mecanismos de transducción. Este conocimiento aportará los elementos necesarios para enfrentar de manera correcta una situación en la cual un paciente presente una alteración gustativa, siendo capaz de identificar las posibles causas y adoptar medidas adecuadas para resolverla y/o tolerarla en el caso de ser provocada en forma transitoria por un procedimiento que forme parte o no de nuestro tratamiento.

The sense organs give to humans the ability to perceive and respond to a wide range of stimuli from the environment. This allows us the power to shape responses in order to adapt to environmental changes, control our basic needs and survive. The sense of taste has a key role in nurture. Enable us to select from a wide variety of foods, elements that are necessary for metabolism and also protecting from potentially harmful compounds, as of its toxicity or degree of decomposition. This sense of taste is also capable of giving us the ability to select and discriminate food that allow us to feel enjoy and pleasure. For dentists is critical to understand adequately the complex processes of taste, identify the structures involved peripheral (papillae, nerve pathways and receptors) and central (nuclei and cerebral cortices), besides knowing the basic modalities of taste and their respective transduction mechanisms. This knowledge will provide the basis to address properly a situation in which a patient has an altered taste, being able to identify possible causes and take appropriate action to resolve it and / or tolerate if temporary caused by a procedure that may be part of our dental treatment.