Extracellular matrix and fibroblast injection produces pterygium-like lesion in rabbits

BACKGROUND: Translational research to develop pharmaceutical and surgical treatments for pterygium requires a reliable and easy to produce animal model. Extracellular matrix and fibroblast are important components of pterygium. The aim of this study was to analyze the effect of the subconjunctival injection of fibroblast cells (NIH3T3 cell line) and exogenous extracellular matrix in rabbits in producing a pterygium-like lesion. METHODS: Six 3-month-old white New Zealand rabbits were injected with 20,000 NIH3T3 cells and 5 µL of Matrigel in the right conjunctiva, and with only 5 µL of Matrigel in the left conjunctiva. The eyes were photographed under a magnification of 16× using a 12-megapixel digital camera attached to the microscope on day 1,3 and 7. Conjunctival vascularization was measured by analyzing images to measure red pixel saturation. Area of corneal and conjunctival fibrovascular tissue formation on the site of injection was assessed by analyzing the images on day 3 and 7 using area measurement software. Histopathologic characteristics were determined in the rabbit tissues and compared with a human primary pterygium. RESULTS: The two treatments promoted growth of conjunctival fibrovascular tissue at day 7. The red pixel saturation and area of fibrovascular tissue developed was significantly higher in right eyes (p < 0.05). Tissues from both treatments showed neovascularization in lesser extent to that observed in human pterygium. Acanthosis, stromal inflammation, and edema were found in tissues of both treatments. No elastosis was found in either treatment. CONCLUSIONS: Matrigel alone or in combination with NIH3T3 cells injected into the rabbits' conjunctiva can promote tissue growth with characteristics of human pterygium, including neovascularization, acanthosis, stromal inflammation, and edema. The combination of Matrigel with NIH3T3 cells seems to have an additive effect on the size and redness of the pterygium-like tissue developed.

Formación en ética y profesionalismo para las nuevas generaciones de médicos / Formação em ética e profissionalismo para as novas gerações de médicos / Training new generations of physicians in ethics and professionalism

La profesión médica es un tipo específico de ocupación que da respuesta a los requerimientos económicos, políticos y sociales de la comunidad. Sin embargo, en el ámbito de las profesiones relacionadas con la salud, dicho concepto trasciende este entorno al entrar en juego la perspectiva ética en la que, idealmente, el profesional de la salud antepone los intereses de los demás a los propios. De esta manera, la profesión médica se convierte en una forma de vida regida por principios éticos y guiada por los más altos estándares de profesionalismo, constituyéndose en una vocación y no en una simple ocupación. Para devolver a la profesión médica su vocación distintiva, es esencial analizar las motivaciones intrínsecas y la ética de vida de las nuevas generaciones de médicos y, a partir de ahí, desarrollar —a manera de competencias— conocimientos, habilidades, actitudes y valores que propicien el desarrollo del profesionalismo, logrando finalmente una mejor relación médico-paciente, situando el bienestar de este último como principal interés.

The medical profession is a specific kind of occupation that responds to the economic, political and social requirements of the community.Nevertheless, in the health care professions, that concept goes even further when the ethical perspective becomes involved. Ideally, health care professionals give priority to the needs of others—individually or collectively— and place their own needs second. In this way, medicine becomes in not just an occupation, but a vocation and a way of life ruled by ethical principles and guided by high professional standards. To restore medicine’s distinctive vocation, it is essential to analyze the intrinsic motivations and life ethics of new generations of physicians and, on that basis, to begin to develop —in the manner of profi ciencies— the knowledge, abilities, attitudes and values that enhance professionalism. In the end, this will provide for a better physician-patient relationship, by invariably giving priority to the patient’s best interests.

A profissão médica é uma ocupação específi ca que responde às demandas econômicas, políticas e sociais da comunidade. No entanto, no domínio das profissões relacionadas com a saúde, o conceito vai além deste ambiente, já que entra em jogo a perspectiva ética, na que –idealmente– o profissional de saúde põe os interesses dos outros acima dos seus próprios. Por tanto, esta profissão torna-se um modo de vida orientado por princípios éticos e guiado por altos padrões de profissionalismo. Conseqüentemente, é uma vocação enão uma simples ocupação. Se desejamos que a profissão retorne a sua vocação distinta, é essencial analisar as motivações intrínsecase a ética de vida das novas gerações de médicos e, a partir daí, desenvolver conhecimento, habilidades, atitudes e valores –semelhantes a competências– conducentes ao desenvolvimento do profissionalismo para conseguir uma melhor relação médico-paciente cujo interesse primário seja o bem-estar de este último.