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1.
Acta Ortop Mex ; 38(2): 82-87, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-38782472

RESUMO

INTRODUCTION: ligamentous injuries of the distal tibiofibular syndesmosis resulting in its opening are common occurrences in traumatology; however, their diagnosis poses a challenge for orthopedic surgeons. The tibioastragaloid mortise radiograph view is the most commonly used method for diagnosing this type of injury, but its reliability is compromised due to variations in ankle positioning during the study, which often depend on the operator. OBJECTIVE: to demonstrate that the designed device achieves a correct and consistent radiographic image of the distal tibiofibular syndesmosis in the mortise view. MATERIAL AND METHODS: we present a prospective, longitudinal, observational study. We designed a polypropylene device that maintains the ankle at 90 degrees of dorsiflexion and 15 degrees of internal rotation. The device was used to take mortise view radiographs of healthy ankles, and corresponding measurements were taken to assess the syndesmosis. RESULTS: we evaluated a total of 46 radiographs of healthy ankles, with a predominance of left ankles. The obtained measurements were as follows: anterior tibiofibular distance (ATFD) ranged from 3 to 6 mm, posterior tibiofibular distance (PTFD) ranged from 1 to 3 mm, tibiofibular clear space (TFCS) ranged from 2 to 3 mm, and a Merle D'Aubigne ratio of 2:1 was observed in all ankles. When comparing the measurements obtained with those established by Harper and Keller, no statistically significant difference was found (2 < 5). CONCLUSION: with the use of the designed device, we achieved a correct and consistent radiographic image of the mortise and the distal tibiofibular syndesmosis.


INTRODUCCIÓN: las lesiones ligamentarias de la sindesmosis tibioperonea distal que ocasionan apertura de la misma son muy frecuentes en traumatología; sin embargo, su diagnóstico es un reto para el cirujano ortopedista. La radiografía de la mortaja tibioastragalina es el método más utilizado para el diagnóstico de este tipo de lesiones, pero es poco confiable ya que la posición del tobillo durante el estudio suele variar dependiendo del operador. OBJETIVO: demostrar que con el uso del dispositivo diseñado se logra una imagen radiográfica correcta y constante de la sindesmosis tibioperonea distal en la proyección de la mortaja. MATERIAL Y MÉTODOS: estudio prospectivo, longitudinal y observacional. Diseñamos un dispositivo de polipropileno que mantiene el tobillo a 90 grados de dorsiflexión y rotación interna de 15 grados. Aplicamos el dispositivo para tomar radiografías de la mortaja en tobillos sanos y les realizamos las mediciones correspondientes para valorar la sindesmosis. RESULTADOS: valoramos un total de 46 radiografías de tobillos sanos, con un predominio de tobillos izquierdos. Las mediciones conseguidas fueron las siguientes: espacio tibioperoneo (ETP) de 3 a 6 mm, la superposición tibioperonea (STP) de 1 a 3 mm, espacio astrágalo-tibial medial (EATM) de 2 a 3 mm y una relación de Merle D'Aubigne de 2:1 en todos los tobillos. Al comparar las mediciones obtenidas con las establecidas por Harper y Keller, no se encontró una diferencia estadísticamente significativa (2 < 5). CONCLUSIÓN: con el uso del dispositivo diseñado, obtuvimos una correcta y constante imagen radiográfica de la mortaja y la sindesmosis tibioperonea distal.


Assuntos
Articulação do Tornozelo , Desenho de Equipamento , Radiografia , Humanos , Estudos Prospectivos , Radiografia/métodos , Masculino , Articulação do Tornozelo/diagnóstico por imagem , Feminino , Adulto , Tíbia/diagnóstico por imagem , Estudos Longitudinais , Fíbula/diagnóstico por imagem , Fíbula/lesões , Tálus/diagnóstico por imagem , Tálus/lesões , Adulto Jovem , Traumatismos do Tornozelo/diagnóstico por imagem , Polipropilenos , Pessoa de Meia-Idade
2.
Rev Sci Instrum ; 93(10): 103517, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319330

RESUMO

The C-2W experimental device at TAE Technologies utilizes neutral beam injection and edge biasing to sustain long-lived, stable field reversed configuration (FRC) plasma. An ongoing effort is under way to optimize the electrode biasing system, which provides boundary control to stabilize the FRC. To this end, tomography offers a powerful and non-invasive technique as tomographic reconstruction of the FRC emission profile provides an important assessment of global stability. Recently, a new signal acquisition system was implemented on a bolometer array dedicated to tomography on C-2W, significantly enhancing the signal-to-noise of the collected data. The array consists of 300 simultaneously digitized photodiode channels that respond to a broad range of wavelengths, from soft x-ray to near-infrared, as well as energetic particles, yielding 180 unique lines of sight that intersect a toroidal plane of the FRC near the mid-plane. Utilizing the collected photo-signals from a set of plasma discharges in which the electrode biasing was intentionally terminated mid-shot, time-resolved reconstruction of the plasma emissivity is achieved via pixel-based 1D and 2D tomographic algorithms, revealing sharply annular profiles with a clear magnetohydrodynamic (MHD) mode structure. In addition, reconstruction of the plasma center-of-emission trajectories via a centroid algorithm applied to the same set of discharges demonstrates a cyclical plasma wobble. Crucially, both the tomography reconstruction and centroid reconstruction indicate an n = 1 toroidal mode that reverses from the electron diamagnetic direction to the ion diamagnetic direction and grows in amplitude after bias termination, qualitatively consistent with the expected stabilizing effect of electrodes.

3.
Int J Biol Macromol ; 109: 1239-1245, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29175525

RESUMO

The inhibition of electrons-holes recombination and enhancement of visible light photocatalytic activity were accomplished by the synthesized TiO2/CS nanocomposites system. In this present work, the different weight ratio of TiO2 and chitosan (75:25, 50:50 and 25:75) nanocomposites were synthesized via two-step method. After that, the existing functional groups, size and structure of the nanocomposites system were characterized via FT-IR, TEM and XRD measurements. The band gap of the prepared materials and its excitation and emission spectra were elevated through UV-vis and PL analyses. Moreover, the MO and MB degradation capability of the synthesized TiO2/CS nanocomposites was optimized, and the outcomes are described in detail.


Assuntos
Quitosana/química , Luz , Nanocompostos/química , Processos Fotoquímicos , Titânio/química , Catálise , Nanopartículas Metálicas/química , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Med Hypotheses ; 85(1): 94-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25913541

RESUMO

Schëuermanns kyphosis is usually observed with a mild idiopathic scoliosis, and there is parity between these two diseases. The aim of this work is to establish a hypothesis about the existence of a biomechanical causal relationship between Schëuermann's kyphosis and scoliosis. To achieve this, a literature review was conducted. A simple mechanical model of the passive thoracolumbar subsystem was created to support part of the discussion. This mechanical model describes the passive thoracolumbar subsystem under ideal conditions of equilibrium. After giving consideration to the system under these conditions, some of the geometrical changes that may be found in Schëuermanns kyphosis are considered. Next, this work discusses the evolution of the spine, taking into account its relationship with stable equilibrium, which the passive subsystem tends toward. We hypothesized about the postural response of the body to compensate for possible situations of imbalance. In conclusion, it can be found that a change in the alignment of the spine may occur due to the postural adaptation of the body to an inadequate mechanical situation that may lead to scoliotic deformity of the spine.


Assuntos
Doença de Scheuermann/fisiopatologia , Escoliose/fisiopatologia , Fenômenos Biomecânicos , Humanos , Doença de Scheuermann/etiologia , Escoliose/etiologia
5.
Emergencias (St. Vicenç dels Horts) ; 26(3): 179-187, jun. 2014. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-124397

RESUMO

Objetivo: Evaluar los efectos de la monitorización continua de indicadores en dos procesos clínicos diferentes en urgencias (manejo de la agudización asmática y atención del cólico nefrítico) y en el uso de fármacos opiáceos mayores; y determinar el efecto de la comunicación de sus resultados a sus profesionales y de las intervenciones formativas encaminadas a la mejora de sus indicadores. Método: En el año 2005 se inició una política de medición sistemática de distintos aspectos de la atención médica en diferentes patologías prevalentes en urgencias de acuerdo a protocolos consensuados y se definieron indicadores para su cuantificación. Cuando se observaban desviaciones destacables de los estándares, se pusieron en marcha sesiones informativas, revisión de casos y acciones formativas continuadas basadas en sesiones clínicas. Se analizan los resultados del periodo 2006-2012. Se cuantificaron mensualmente de forma retrospectiva los siguientes indicadores: A) agudización asmática: registro de la frecuencia respiratoria, realización del peak-flow, radiografía de tórax y gasometría arterial, e indicación de ingreso; B) cólico nefrítico: medición del grado de dolor mediante una escala de categoría numérica (ECN), realización de radiología de abdomen y de ecografía, interconsulta al servicio de urología, ingreso en observación de urgencias o en hospitalización y reatenciones en urgencias en menos de 72 horas; y C) empleo de opiáceos mayores en los procesos habituales. Resultados: Se evaluaron 1.767 agudizaciones asmáticas 6.114 cólicos nefríticos y la administración de 22.751 ampollas de opiáceos. Se incluyó el 100% de los registros. En 2006, la mayoría de indicadores se encontraban por debajo de los estándares recomendados. Las acciones formativas evidenciaron mejoras discretas (en algunos casos estadísticamente significativas): A) agudización asmática: aumentó la medición de frecuencia respiratoria (p = 0,13) y disminuyeron las radiografías (p < 0,05), gasometrías arteriales (p = 0,66) e ingresos en planta (p = 0,66): B) cólico nefrítico: incrementaron la medición del dolor (p = 0,59), los ingresos en observación (p < 0,001), y disminuyeron radiografías (p < 0,01) y ecografías (p = 0,07), interconsultas con urología (p<0,05), ingresos hospitalarios (p = 0,01) y reatenciones a las 72 horas (p < 0,55); y C) incrementó el uso de opiáceos mayores para el control del dolor (p = 0,001). Al final del periodo, sólo en 4 de 13 indicadores se había alcanzado el estándar propuesto. Conclusión: La monitorización continua de procesos clínicos asociada a una estrategia predefinida de mejora continua basada en la definición de criterios de calidad en los procesos clínicos, la medición sistemática mediante indicadores y la comunicación de los resultados a los profesionales tienen efectos positivos, aunque éstos son discretos y se hacen más evidentes en el medio y largo plazo


Objectives: To assess the effect of ongoing measurement of quality indicators affecting 2 different clinical processes that are highly prevalent in emergency care (acute asthma exacerbation and nephritic colic) and also on the use of major opiates; to determine the effect of giving staff information about the results of measurements and providing training on how to improve the quality indicators. Methods: Systematic recording of measures relating to various aspects of care for processes that are highly prevalent in the emergency department caseload. Records were started in 2005. The quality-of-care indicators reflected consensusbased protocols. When substantial deviations from recommendations were identified, sessions to provide information and training were scheduled. The sessions included reviews of cases. The results of these strategies were analyzed for 2006 through 2012. Statistics on the following indicators were compiled retrospectively month by month. For asthma exacerbations, we compiled data on the recording of respiratory frequency and peak-flow volume, the ordering of chest x-rays and arterial blood gas analysis, and admissions. For nephritic colic, we examined the recording of pain assessment on a categorical numerical pain scale, the ordering of abdominal x-rays and ultrasound imaging, urology consultations, admissions to the observation area or hospital ward, and emergency revisits within 72 hours. We also collected data on the use of major opiates. Results: A total of 1767 asthma exacerbations, 6114 cases of nephritic colic, and 22 751 prescriptions for opiates were evaluated during the study period. All records were included. Most quality indicators failed to meet recommended levels in 2006. The training strategy led to small changes, only some of which reached statistical significance. In the treatment of asthma exacerbation, the number of x-rays ordered decreased (P<.05). The measurement of respiratory frequency tended to rise in frequency but the difference was not significant (P=.13), and the frequencies of orders for arterial blood gas analyses and rates of hospital admissions were similar (P=.66 in both cases). In the treatment of nephritic colic, admissions to the observation area increased (P<.001) and hospital admissions decreased (P=.01). Urology consultations and the number of x-rays also decreased (P<.05 and P<.01, respectively), while the number of ultrasound imaging studies tended to decrease (P=<.07). Revisits remained similar (P<.55). The use of opiates for pain control increased (P=.001). Targets had been reached for only 4 of 13 indicators at the end of the study period. Conclusions: The systematic monitoring of statistics on clinical processes as part of a strategy to improve quality-of-care indicators and feedback on results during training sessions has had some positive effects. However, the changes have been small and they became evident only over the medium to long term


Assuntos
Humanos , Melhoria de Qualidade , Serviços Médicos de Emergência/organização & administração , Cólica Renal/epidemiologia , Estado Asmático/epidemiologia , Indicadores de Qualidade em Assistência à Saúde , Tratamento de Emergência/métodos
6.
Mol Psychiatry ; 19(10): 1095-105, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24732670

RESUMO

Circulating triglycerides (TGs) normally increase after a meal but are altered in pathophysiological conditions, such as obesity. Although TG metabolism in the brain remains poorly understood, several brain structures express enzymes that process TG-enriched particles, including mesolimbic structures. For this reason, and because consumption of high-fat diet alters dopamine signaling, we tested the hypothesis that TG might directly target mesolimbic reward circuits to control reward-seeking behaviors. We found that the delivery of small amounts of TG to the brain through the carotid artery rapidly reduced both spontaneous and amphetamine-induced locomotion, abolished preference for palatable food and reduced the motivation to engage in food-seeking behavior. Conversely, targeted disruption of the TG-hydrolyzing enzyme lipoprotein lipase specifically in the nucleus accumbens increased palatable food preference and food-seeking behavior. Finally, prolonged TG perfusion resulted in a return to normal palatable food preference despite continued locomotor suppression, suggesting that adaptive mechanisms occur. These findings reveal new mechanisms by which dietary fat may alter mesolimbic circuit function and reward seeking.


Assuntos
Encéfalo/metabolismo , Comportamento Alimentar/fisiologia , Motivação/fisiologia , Recompensa , Triglicerídeos/sangue , Anfetamina/farmacologia , Animais , Artérias Carótidas/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia , Lipase Lipoproteica/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia
8.
Oecologia ; 173(1): 83-93, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23386048

RESUMO

Animals often announce their unprofitability to predators through conspicuous coloured signals. Here we tested whether the apparently conspicuous colour designs of the four European Coraciiformes and Upupiformes species may have evolved as aposematic signals, or whether instead they imply a cost in terms of predation risk. Because previous studies suggested that these species are unpalatable, we hypothesized that predators could avoid targeting them based on their colours. An experiment was performed where two artificial models of each bird species were exposed simultaneously to raptor predators, one painted so as to resemble the real colour design of these birds, and the other one painted using cryptic colours. Additionally, we used field data on the black kite's diet to compare the selection of these four species to that of other avian prey. Conspicuous models were attacked in equal or higher proportions than their cryptic counterparts, and the attack rate on the four species increased with their respective degree of contrast against natural backgrounds. The analysis of the predator's diet revealed that the two least attacked species were negatively selected in nature despite their abundance. Both conspicuous and cryptic models of one of the studied species (the hoopoe) received fewer attacks than cryptic models of the other three species, suggesting that predators may avoid this species for characteristics other than colour. Globally, our results suggest that the colour of coraciiforms and upupiforms does not function as an aposematic signal that advises predators of their unprofitability, but also that conspicuous colours may increase predation risk in some species, supporting thus the handicap hypothesis.


Assuntos
Comunicação Animal , Aves/anatomia & histologia , Cor , Comportamento Predatório , Aves Predatórias/fisiologia , Animais , Sinais (Psicologia) , Dieta , Fatores de Risco
9.
Oecologia ; 173(2): 399-408, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23443357

RESUMO

Chromatic signals of offspring quality have been shown to play a role in parent-offspring communication in diurnal birds, but are assumed to be useless in dim light conditions because colour-based discrimination probably requires more light. A major ecological and evolutionary conundrum in this scenario is why the nestlings of some nocturnal owls display colourful beaks. Here, we test the hypothesis that yellow bill coloration of owlets of the nocturnal little owl Athene noctua may function as a chromatic signal revealing to parents aspects of quality of their offspring. In a first step, we examined physical variation in bill coloration and its covariation with owlet quality. Secondly, we studied parental provisioning in relation to an experimental manipulation of bill coloration of owlets. Bills of owlets showed higher within-nest variation in yellow-red chroma than in brightness. Plasma carotenoid concentration and nestling immunological status were not associated with chromatic or achromatic features of the bill. Interestingly, however, heavier owlets displayed more yellow bills than lighter ones. The effect of bill coloration on parental favouritism changed with brood size. Parents holding large broods preferentially fed owlets with enhanced over reduced yellow bill coloration, whereas those with small broods did not significantly bias feeding in relation to owlet bill coloration. Our results, based on integration of objective spectrophotometric assessment of colour and experimental procedures, confirm that parent little owls use bill coloration to reveal information on owlet body mass to adjust their feeding strategies, thus highlighting the importance of considering potential chromatic signals for a full comprehension of parent-offspring communication processes in nocturnal bird species.


Assuntos
Cor , Comportamento de Nidação , Pigmentação , Estrigiformes/fisiologia , Animais , Carotenoides/sangue , Cromatografia Líquida de Alta Pressão , Fenótipo , Espanha , Análise Espectral , Percepção Visual
13.
Actas Dermosifiliogr ; 103(1): 44-50, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22464597

RESUMO

BACKGROUND: The melanocortin-1 receptor (MC1R) is an important risk factor for melanoma due to its role in the production of melanin in response to sun exposure. OBJECTIVES: To analyze the phenotypic and histologic characteristics of cutaneous melanoma in patients carrying mutations in MC1R and assess the influence of sun exposure on the occurrence of melanoma. MATERIAL AND METHODS: A total of 224 patients with a diagnosis of melanoma seen in the Department of Dermatology at Hospital General Universitario Gregorio Marañón in Madrid, Spain between September 2004 and December 2009 were included in the study. The genomic sequence of MC1R was analyzed by polymerase chain reaction. RESULTS: At least one of the following MC1R variants was present in 58% of the patients: V60L, V92M, I155T, R160W, D294H, and R163Q. Carriers of those variants had a history of sunburn (P=.018) and melanomas located on areas with intermittent sun exposure (P=.019), and the majority had a diagnosis of superficial spreading melanoma. These associations were especially significant in patients with the R160W and D294H variants. Carriers of R160W also had melanomas associated with melanocytic nevi (P=.028). CONCLUSIONS: The results of our study suggest that there may be a relationship between the expression of certain MC1R variants and sun exposure, history of sunburn, and skin type. They also indicate a higher frequency of superficial spreading melanomas and melanomas associated with melanocytic nevi in patients carrying certain mutations in MC1R.


Assuntos
Melanoma/genética , Proteínas de Neoplasias/genética , Neoplasias Induzidas por Radiação/genética , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Luz Solar/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , DNA de Neoplasias/genética , Feminino , Humanos , Masculino , Melanoma/epidemiologia , Melanoma/etiologia , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/patologia , Nevo Pigmentado/epidemiologia , Nevo Pigmentado/genética , Fenótipo , Receptor Tipo 1 de Melanocortina/fisiologia , Análise de Sequência de DNA , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologia , Espanha/epidemiologia , Queimadura Solar/epidemiologia , Adulto Jovem
14.
Biol Lett ; 8(4): 502-4, 2012 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-22399785

RESUMO

Many animals react to danger by producing chemical cues that can be smelled by others, which is called the smell of fear. Some bird species produce chemical compounds when threatened, such as nestlings of the Eurasian roller Coracias garrulus that vomit an odorous orange liquid when scared in their nests. Here, we experimentally explore the possibility that parents were informed about recent predation attempts at their nests through the olfaction of this vomit. Parents of nests treated with nestling vomit delayed their entrance to nests and decreased their provisioning rate in comparison with parents of nests treated with an odorous control. These results demonstrate that adult rollers are able to smell the fear of offspring and show for the first time in birds that a scent produced during an interspecific challenge has a role in an intraspecific communication scenario.


Assuntos
Comportamento Animal/fisiologia , Aves/fisiologia , Medo/psicologia , Comportamento de Nidação/fisiologia , Olfato/fisiologia , Animais , Sinais (Psicologia) , Odorantes , Especificidade da Espécie
15.
Actas dermo-sifiliogr. (Ed. impr.) ; 103(1): 44-50, ene.-feb. 2012.
Artigo em Espanhol | IBECS | ID: ibc-101175

RESUMO

Introducción: El receptor de la melanocortina-1 (MC1R) es un importante determinante del riesgo de melanoma debido a su función en la producción de melanina en respuesta a la exposición solar. Objetivos: Analizar las características fenotípicas e histológicas de los pacientes con melanoma cutáneo portadores de mutaciones del MC1R asociadas a riesgo de melanoma y la influencia de la exposición solar en la aparición del melanoma. Material y métodos: Se incluyeron 224 pacientes diagnosticados de melanoma atendidos en el Servicio de Dermatología del Hospital General Universitario Gregorio Marañón (septiembre de 2004 -diciembre de 2009). Se realizó la secuenciación genómica del ADN del MC1R mediante PCR. Resultados: El 58% presentaba al menos una de las siguientes variantes de MC1R (V60L, V92M, I155T, R160W, D294H, R163Q). Estos pacientes presentaban antecedentes de quemaduras solares (p=0,018), melanomas localizados en áreas de exposición solar intermitente (p=0,019), con predominio del tipo histológico de extensión superficial. Estas asociaciones fueron especialmente significativas en los portadores de las variantes R160W y D294H. Los portadores de R160W presentaron además melanomas asociados a nevus melanocíticos (p=0,028). Conclusión: Los resultados obtenidos sugieren que puede existir una relación entre la expresión de determinadas variantes de MC1R y los hábitos de exposición solar, antecedentes de quemadura y tipo de piel del paciente, así como una mayor frecuencia de melanomas de extensión superficial y melanomas asociados a nevus en portadores de ciertas mutaciones de MC1R (AU)


Background: The melanocortin-1 receptor (MC1R) is an important risk factor for melanoma due to its role in the production of melanin in response to sun exposure. Objectives: To analyze the phenotypic and histologic characteristics of cutaneous melanoma in patients carrying mutations in MC1R and assess the influence of sun exposure on the occurrence of melanoma. Material and methods: A total of 224 patients with a diagnosis of melanoma seen in the Department of Dermatology at Hospital General Universitario Gregorio Marañón in Madrid, Spain between September 2004 and December 2009 were included in the study. The genomic sequence of MC1R was analyzed by polymerase chain reaction. Results: At least one of the following MC1R variants was present in 58% of the patients: V60L, V92M, I155T, R160W, D294H, and R163Q. Carriers of those variants had a history of sunburn (P=.018) and melanomas located on areas with intermittent sun exposure (P=0.019), and the majority had a diagnosis of superficial spreading melanoma. These associations were especially significant in patients with the R160W and D294H variants. Carriers of R160W also had melanomas associated with melanocytic nevi (P=0.028). Conclusions: The results of our study suggest that there may be a relationship between the expression of certain MC1R variants and sun exposure, history of sunburn, and skin type. They also indicate a higher frequency of superficial spreading melanomas and melanomas associated with melanocytic nevi in patients carrying certain mutations in MC1R (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Melanoma/epidemiologia , Melanoma/fisiopatologia , Queimadura Solar/complicações , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 1 de Melanocortina/imunologia , Neoplasias Cutâneas/diagnóstico , Genômica/métodos , Sequência de DNA Instável/genética , Sequência de DNA Instável/fisiologia , Nevo/diagnóstico , Radiação Solar/efeitos adversos , Queimadura Solar/imunologia , Queimadura Solar/patologia , Melanoma/genética , Melanoma/imunologia , Hospitais Universitários/economia , Hospitais Universitários
16.
Actas Dermosifiliogr ; 103(1): 44-50, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-21737053

RESUMO

BACKGROUND: The melanocortin-1 receptor (MC1R) is an important risk factor for melanoma due to its role in the production of melanin in response to sun exposure. OBJECTIVES: To analyze the phenotypic and histologic characteristics of cutaneous melanoma in patients carrying mutations in MC1R and assess the influence of sun exposure on the occurrence of melanoma. MATERIAL AND METHODS: A total of 224 patients with a diagnosis of melanoma seen in the Department of Dermatology at Hospital General Universitario Gregorio Marañón in Madrid, Spain between September 2004 and December 2009 were included in the study. The genomic sequence of MC1R was analyzed by polymerase chain reaction. RESULTS: At least one of the following MC1R variants was present in 58% of the patients: V60L, V92M, I155T, R160W, D294H, and R163Q. Carriers of those variants had a history of sunburn (P=.018) and melanomas located on areas with intermittent sun exposure (P=.019), and the majority had a diagnosis of superficial spreading melanoma. These associations were especially significant in patients with the R160W and D294H variants. Carriers of R160W also had melanomas associated with melanocytic nevi (P=.028). CONCLUSIONS: The results of our study suggest that there may be a relationship between the expression of certain MC1R variants and sun exposure, history of sunburn, and skin type. They also indicate a higher frequency of superficial spreading melanomas and melanomas associated with melanocytic nevi in patients carrying certain mutations in MC1R.


Assuntos
Melanoma/genética , Melanoma/patologia , Mutação , Polimorfismo Genético , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
18.
Actas Dermosifiliogr ; 102(8): 623-6, 2011 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-21349475

RESUMO

The diagnosis of pigmented actinic keratosis can be complicated in clinical practice. The differential diagnosis with lentigo maligna melanoma can be difficult due to common clinical and dermoscopic characteristics. We present 5 cases of pigmented actinic keratosis in 4 patients. The most common dermoscopic finding was a grayish-brown granulation with a perifollicular distribution, present in all lesions, followed by rhomboidal structures in 4 cases, and an annular-granular pattern in 3. In no case were asymmetrical pigmented follicular openings observed. We draw attention to key findings that aid preoperative diagnosis of pigmented actinic keratosis.


Assuntos
Dermoscopia , Dermatoses Faciais/diagnóstico , Ceratose Actínica/diagnóstico , Nariz/patologia , Pigmentação da Pele , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Epiderme/química , Epiderme/patologia , Dermatoses Faciais/patologia , Dermatoses Faciais/cirurgia , Feminino , Humanos , Sarda Melanótica de Hutchinson/diagnóstico , Queratinócitos/ultraestrutura , Ceratose Actínica/patologia , Ceratose Actínica/cirurgia , Masculino , Melaninas/análise , Pessoa de Meia-Idade
20.
J Evol Biol ; 24(2): 314-25, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21054625

RESUMO

The obligate avian brood parasitic common cuckoo Cuculus canorus comprises different strains of females that specialize on particular host species by laying eggs of a constant type that often mimics those of the host. Whether cuckoos are locally adapted for mimicking populations of the hosts on which they are specialized has never been investigated. In this study, we first explored the possibility of local adaptation in cuckoo egg mimicry over a geographical mosaic of selection exerted by one of its main European hosts, the reed warbler Acrocephalus scirpaceus. Secondly, we investigated whether cuckoos inhabiting reed warbler populations with a broad number of alternative suitable hosts at hand were less locally adapted. Cuckoo eggs showed different degrees of mimicry to different reed warbler populations. However, cuckoo eggs did not match the egg phenotypes of their local host population better than eggs of other host populations, indicating that cuckoos were not locally adapted for mimicry on reed warblers. Interestingly, cuckoos exploiting reed warblers in populations with a relatively larger number of co-occurring cuckoo gentes showed lower than average levels of local adaptation in egg volume. Our results suggest that cuckoo local adaptation might be prevented when different cuckoo populations exploit more or fewer different host species, with gene flow or frequent host switches breaking down local adaptation where many host races co-occur.


Assuntos
Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Evolução Biológica , Aves/genética , Aves/fisiologia , Comportamento de Nidação , Animais , Demografia , Europa (Continente) , Feminino , Variação Genética , Óvulo
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