Morfología y morfometría del endotelio corneal en adultos sin alteraciones corneales / Morphology and morphometry of the corneal endothelium in adults without corneal alterations

Objetivo: describir las características morfológicas y morfométricas del endotelio corneal en adultos sin alteraciones corneales atendidos en el Servicio de Córnea del Instituto Cubano de Oftalmología Ramón Pando Ferrer en el período comprendido de enero a julio del año 2015. Métodos: se realizó una investigación descriptiva de corte transversal de serie de casos, en el Servicio de Córnea. Después de aplicar los criterios de exclusión, la muestra quedó conformada por 324 ojos de 162 pacientes adultos. Se realizó microscopia endotelial de no contacto SP-3000P, para identificar los valores morfológicos (hexagonalidad-coeficiente de variabilidad) y morfométricos (densidad celular-paquimetría) y el promedio del tamaño celular. Resultados: según los grupos de edades, no hubo diferencias en cuanto a la paquimetría en ambos ojos (p> 0,05). En relación con la densidad, existieron diferencias significativas entre los diferentes grupos de edades en ambos ojos (p< 0,001). Los valores de las medias de la hexagonalidad y del coeficiente de variabilidad no mostraron diferencias significativas (p> 0,05) en ambos ojos. Los valores de las medias del tamaño celular promedio según grupos de edades fueron diferentes de forma significativa en ambos ojos (p< 0,001). No existieron diferencias significativas (p< 0,05) entre los sexos según ojos derecho e izquierdo. Conclusiones: el estudio del endotelio corneal mediante la utilización del microscopio especular constituye un método efectivo que permite conocer las características de las células endoteliales(AU)

Objective: to describe the morphological and morphometric characteristics of the corneal endotelium in adults without corneal alterations at the cornea care service of Ramón Pando Ferrer Cuban Institute of Ophthalmology in the period of January to July 2015. Methods: descriptive, cross-sectional case series study conducted in a final sample of 324 eyes from 162 adult patients at the cornea care service after using the exclusion approaches. SP-3000P non-contact endothelial microscopy was performed to identify the morphological (hexagonality and variability coefficient) and morphometric (cellular density-pachymetry) values as well as the average cell size. The analyzed period embraced from January to July of 2015. Results: there were no differences as for the pachymetry in both eyes (p>0,05) by age groups. Regarding density, significant differences in both eyes among the different group ages (p< 0,001) were found. The mean values of hexagonality and the variability coefficient did not show significant differences (p> 0.05) in both eyes. The mean values of the average cell size by age groups were significantly different in both eyes (p< 0.001). Significant differences were not found (p< 0.05) between sexes in terms of the left and right eyes. Conclusions: the study of the corneal endothelium by means of the specular microscope is an effective method that allows identifying the endothelial cell characteristics(AU)

Morfología y morfometría del endotelio corneal / Morphometry and morphology of the corneal endothelium

El estudio de parámetros morfológicos y morfométricos del endotelio corneal en poblaciones de individuos sanos ha sido motivo de diversas investigaciones a nivel internacional en los últimos años. La microscopia especular permite una visión clara de las células endoteliales vivas sin alterar su función ni su morfología. A su vez, se puede realizar un recuento por área de superficie y determinar si existe una alteración en la forma o tamaño de las células endoteliales, parámetros a tener en cuenta para conocer la capacidad funcional del endotelio corneal. Se realizó una búsqueda actualizada de los últimos diez años de diversos artículos publicados, con el objetivo de conocer las características cuantitativas y cualitativas de las células endoteliales en las diferentes poblaciones estudiadas. Se utilizó la plataforma Infomed, específicamente la Biblioteca Virtual de Salud(AU)

The study of morphological and morphometric parameters of the corneal endothelium in healthy individuals have been the main subject of several research studies at international level in the last few years. The specular microscopy allows us a clear vision of the alive endothelial cells without altering either their function or their morphology; a counting per surface area can be made and to determine whether an alteration exists in the form or the size of the endothelial cell, this is a parameter to be kept in mind to know the functional capacity of the corneal endothelium. An updated search of the published articles in the last ten years was made with the objective of determining the quantitative and qualitative characteristics of the endothelial cells in the different studied populations. Infomed platform, particularly the Virtual Library of Health, was used to this end(AU)

Síndrome de Chandler / Chandler's syndrome

El síndrome de Chandler es una de las variaciones clínicas del síndrome iridocorneoendotelial, donde el denominador común es una alteración del endotelio corneal cuyo diagnóstico es, en ocasiones, muy difícil de realizar por la complejidad y la variabilidad de sus signos y síntomas. Se presenta una paciente de 67 años con disminución importante de la visión del ojo izquierdo. A la exploración existía un edema corneal severo, una midriasis pupilar, una corectopia leve hacia el sector temporal con tracción iridiana hacia el ángulo y sinequias anteriores angulares en el lado de la corectopia. La realización de un recuento endotelial demostró alteraciones cuali y cuantitativas del endotelio en el ojo izquierdo. Se concluyó que la microscopia especular es fundamental para el diagnóstico y la evaluación en casos sospechosos de síndrome de Chandler(AU)

Chandler's syndrome is a clinical variant of the iridocorneal endothelial syndrome in which the common aspect is the altered corneal endothelium that is sometimes very difficult to be diagnosed on account of the complexity and variability of signs and symptoms. This article was aimed at showing the effectiveness of specular microscopy for diagnosis. Here is a 67 years-old female patient who had significant reduction of vision in her left eye. On examination, there were observed severe corneal edema, pupillary mydriasis, mild corectopia towards the temporal sector with angled iridal traction and anterior angle synechias on the corectopia side. The endothelial counting revealed qualitative and quantitative alterations in the left eye. It was concluded that the specular microscopy is the key to diagnosis and assessment of suspected Chandler's syndrome cases(AU)

Microscopic versus endoscopic approach to the sellar and supprasellar space, a cadaveric study

Skull base endoscopic endorasal approaches are used more and more liberally to expose the skull base transnasally. However the surgical microscope is still used by some surgeons for sellar exposure transnasally. To provide a qualitative and quantitative anatomical evaluation of the surgical exposure and maneuverability afforded by the endoscope versus that of the surgical microscope in exploring the sellar / suprasellar areas. We used seven embalmed cadaver heads whose vascular system had been injected with colored silicon material. Sublabial trans-septal exploration of the sellar/suprasellar areas was conducted using the endoscope and then microscope. The exposure and maneuverability associated with each mode were evaluated. The endoscope exposed the sellar/superasellar compartment better than the microscope in terms of maneuverability and surgical field exposure. In our model, use of the endoscope provided a better maneuverability advantage over microscope mode in the exploration of the suprasellar compartment

Efeitos da luz UV-A e visível em células da pele e no cabelo / Effects UV-A and visible light on skin cells and hair

A luz solar apresenta ondas eletromagnéticas em ampla faixa espectral, incluindo as regiões do ultravioleta (UV-C, UV-B, UV-A), visível e infravermelho. Cada região interage com a pele de forma dependente da fotofísica e da fotoquímica dos seus respectivos compostos absorvedores. A luz UV-A causa a geração de espécies reativas de oxigênio e de nitrogênio (EROs e ERNs) através da fotossensibilização de moléculas endógenas (co-enzimas de flavina, porfirinas, melaninas). Quando fotossensibilizadores produzem quantidades de EROs e ERNs maiores do que a capacidade celular de supressão destas espécies, caracteriza-se um quadro de desbalanço redox, que causa lesão em biomoléculas como os ácidos nucleicos, lipídeos e as proteínas. Essas lesões podem levar à morte celular ou a outras transformações fenotípicas e genotípicas e também estimulam a liberação de citocinas pró-inflamatórias. Com a finalidade de melhor compreender a dinâmica dos mecanismos de resposta celular após exposição ao UV-A e ao visível, nós caracterizamos inicialmente as propriedades fotofísicas da melanina e detectamos a produção de oxigênio singlete (1O2) pela fotossensibilização no visível e a supressão desta espécie excitada pela reação do oxigênio singlete com a dupla ligação reativa dos grupos indóis presentes na melanina. Estes processos também foram observados no cabelo e levaram-nos a propor um modelo que explica o efeito da luz visível na estrutura e cor dos cabelos. Demonstramos também que a feomelanina produz mais (30%) 1O2 do que a eumelanina, que sofre maior modificação na sua estrutura por fotodegradação. O efeito destes processos na pele foi estudado a nível celular. Demonstramos que células epiteliais com maior teor de melanina apresentaram maior geração de 1O2 que causa lesão no DNA e morte necro-apoptótica após irradiação com luz visível. A foto-oxidação da melanina pela luz visível nos motivou a estudar um pigmento que fosse foto-protetor não somente contra luz UV-B mas também contra luz visível. A pigmentação com Acetil-Tirosina se mostrou atóxica e protetora contra luz UV-B e visível ao contrário do pigmento com tirosina, que se mostrou protetor do UV-B mas tóxico no visível. Este efeito foi relacionado com a localização celular do polímero e não com a estrutura do mesmo. A luz UV-A, por sua vez, promove o acúmulo de lipofuscina dentro dos vacúolos autofágicos de queratinócitos da pele e que também ativa a fototoxicidade pela luz visível. A lipofuscina dentro dos vacúolos autofágicos é foto-oxidada pela luz visível, causando lesão no DNA e morte celular programada tipo II. Doses UV-A que desencadeiam a liberação de citocinas também foram caracterizados

Sunlight presents electromagnetic radiation over a wide spectral range, including the regions of ultraviolet (UV-C, UV-B, UV-A), visible and infrared. Each region interacts with skin dependending on the photophysics and photochemistry of the respective absorbing compounds. UV-A light causes the generation of reactive oxygen and nitrogen species (ROS and RNS) by photosensitization of endogenous molecules (flavin coenzymes, porphyrins, melanins). When photosensitizers produce amounts of ROS and RNS larger than the cell capacity to suppress these species, a set of redox imbalance, which damages biomolecules such as nucleic acids, lipids and proteins. This damage cause cell death and to other phenotypic and genotypic changes and also stimulates the release of proinflammatory cytokines. In order to better understand the dynamics of the mechanisms of cellular responses after exposure to UV-A and visible light, we initially characterized the photophysical properties of melanin and detected the production of singlet oxygen (1O2) by photosensitization in the visible, as well as the suppression of these excited species by reaction of singlet oxygen with the double bonds of the reactive groups presented in the melanin indols. These processes were also observed in hair and led us to propose a model that explains the effects of visible light on the structure and color of hair. We also demonstrated that pheomelanin produces more (30%) 1O2 than eumelanin, which undergoes a quick change on its structure by photodegradation. The effect of these processes in the skin was studied at the cellular level. We demonstrated that epithelial cells with larger melanin content have stronger generation of 1O2, which causes DNA damage and necro-apoptotic death after irradiation with visible light. The photo-oxidation of melanin by visible light has motivated us to study a pigment that was not only able to protect against UV-B but also against visible. Pigmentation with Acetyl-Tyrosine proved nontoxic and protective against UV-B and visible light instead of pigmentation with Tyrosine, which shielded against UV-B but showed toxicity in the visible. This effect was associated with the polymer, cell location and not with its structure. UV-A light, in turn, promotes the accumulation of lipofuscin, within autophagic vacuoles of keratinocytes also enabling phototoxicity in the visible light. The lipofuscin within the autophagic vacuoles is fotooxidized by visible light, causing DNA damage and programmed cell death type II. Linear dose of UV-A that trigger the release of cytokines were also characterized

Pre-Auricular sinus: review and comparative study of surgical techniques

To determine the role of operating microscope in excision of preauricular sinus. A retrospective study. From January 2005 to July 2006 at Mayo Hospital, Lahore. All the patients who underwent preauricular sinus excision under operating microscope were studied. Patients reviewed in follow up for recurrence of sinus and other complications. A follow up of all operated patients for a period of minimum of 8 months revealed good results without any recurrence. Magnification employed during surgery minimizes the risk of recurrence of preauricular sinuses

Comparing the results of light microscopy with the results of PCR method in the diagnosis of Plasmodium vivax.

BACKGROUND AND OBJECTIVES: Although polymerase chain reaction (PCR) is a new technique in the diagnosis of malaria with very high accuracy; light microscopy is still conventional diagnostic method in Iran. In this study we checked the accuracy of light microscopy using the results of PCR as gold standard in Iran. METHODS: The blood samples were collected from 124 febrile cases in Kahnooj district. The blood slides were read by microscopists, and double checked by experts in provincial referral laboratory. DNA samples were processed by PCR to amplify species-specific sequences of 18s subunit ribosomal ribonucleic acid (18ssrRNA) genes of Plasmodium vivax and P. falciparum. RESULTS: The sensitivity and specificity of microscopy in the detection of Plasmodium spp infection were 77% (95% CI: 46-94%) and 100% (95% CI: 95-100%), correspondingly. Also, the estimated positive and negative predictive values were 100% (95% CI: 66-100%) and 97% (95% CI: 91-99%), respectively. INTERPRETATION AND CONCLUSION: According to these results, we believe that the accuracy of light microscopy in the diagnosis of malaria in Kahnooj was acceptable. Expert micorscopists in endemic areas of Iran such as Kahnooj and available equipments in one hand and expensive PCR test on the other hand may convince that in current situation we do not have to change the diagnostic method.

[Evaluation of neurotoxic effects of lead acetate on rat radial nerve]

Lead toxicity is a common popular problem. Many researches were performed about this toxicity both in-vivo and in-vitro since 100 years ago.Those studies showed that lead have toxic effects such as behavioral disorders, decrease of IQ and decrease of learning and memory. Also lead has neurotoxic effects such as decrease of neuronal density in visual cortex of monkey, cell death in hippocampus and decrease of acetylcolin in rat's hippocampus. In this study we examin neurotoxic effects of lead on rat's radial nerve because radial nerve is a mix nerve. 24 adult male rats were divided in six groups. Groups I and II received lead acetate 4% and 2%, groups III and IV received distilled water and normal water for one month. After this time, we killed rats and exposed radial nerve from behind of arm. Then studied them with light and electron microscopy. In experimental groups we saw decrease of myelin sheath diameter and decrease of nuclear density in schwann cell. Also we saw many granules in mitochondrial matrix, active macrophage, edema and disarrangement of myelin sheath layers. We suggest that lead neurophaty is due to schwann cell injury and this lesion lead to decrease of myelin sheath

Forum / Forum

Na ediçäo de junho 1994, tivemos a oportunidade de disutir alguns dos mais recentes avanços terapêuticos e de diagnóstico colocamos ao nosso alcance, tentando esclarecer as reais e falsas expectativas que geralmente cercam a incorporaçäo de tais recursos ao nosso dia a dia. Aproveitamos para chamar a atençäo de nossos leitores , que os tópicos aqui apresentados se encontram em permanente discussäo. Aqueles que qeuiserem tirar dúvidas, manifestar opiniöes ou descrever experiências pessoais diversas daquelas aquimostradas, poderäo se valer deste espaço, escrevendo diretamente para o Coordenador do Forum. Contamos com sua participaçäo

Estudio del adaptado marginal de coronas completas de resina compuesta termopolimerizada al microscopio estereoscopico / Study marginal adaptate complete crowns of thermopolimerizate compounds resin to steroscopy microscope

Para este trabajo de investigación se confeccionaron doce coronas completas de SR-ISOSIT-N, colocadas en doce ceninos naturales extraidos por razones periodontales. En cuanto a las características del tallado en el retenedor y los procedimientos de laboratorio, se realizaron según las especificaciones del fabricante Adicionalmente, en los procedimientos de toma de impresión, montaje para la elaboración de tromqueles, se siguieron los principios generales utilizados en la técnica para coronas completas. Una vez realizadas las doce coronas completas de SR-ISOSIT-T y colocadas cada una en sus repectivos caninos extraidos, se midió la separación existente entre la terminación marginal gingival del diente y el margen gingival de la restauración. Para tal fin, se analizaron los especímenes al microscopio ESTEREOSCOPICO a un aumento de 1.6x en cada una de las cuatro caras del conjunto restauración-diente, y se obtuvieron de esta manera cuatro fotos (vestibular, palatino, mesial y distal) por cada restauración confeccionada, las cuales se sometieron a mediciones. Los resultados de estas mediciones permitió establecer que dicha resina compuesta sufrió una contracción de polimerización. La separación gingival existe entre la restauración y la terminación gingival del diente también es bastante grande. Todo esto permitió concluir que las coronas completas confeccionadas con SR-ISOSIT-N pueden indicarse como una alternativa de tratamiento intermedio, en pacientes de bajos resursos económicos, en dientes con pronóstico reservado y en adultos jóvenes.