Age-related functional and structural retinal modifications in the Igf1−/− null mouse

Background. Mutations in the gene encoding human insulin-like growth factor-I (IGF-I) cause syndromic neurosensorial deafness. To understand the precise role of IGF-I in retinal physiology, we have studied the morphology and electrophysiology of the retina of the Igf1−/− mice in comparison with that of the Igf1+/− and Igf1+/+ animals during aging. Methods. Serological concentrations of IGF-I, glycemia and body weight were determined in Igf1+/+, Igf1+/− and Igf1−/− mice at different times up to 360 days of age. We have analyzed hearing by recording the auditory brainstem responses (ABR), the retinal function by electroretinographic (ERG) responses and the retinal morphology by immunohistochemical labeling on retinal preparations at different ages. Results. IGF-I levels are gradually reduced with aging in the mouse. Deaf Igf1−/− mice had an almost flat scotopic ERG response and a photopic ERG response of very small amplitude at postnatal age 360 days (P360). At the same age, Igf1+/− mice still showed both scotopic and photopic ERG responses, but a significant decrease in the ERG wave amplitudes was observed when compared with those of Igf1+/+ mice. Immunohistochemical analysis showed that P360 Igf1−/− mice suffered important structural modifications in the first synapse of the retinal pathway, that affected mainly the postsynaptic processes from horizontal and bipolar cells. A decrease in bassoon and synaptophysin staining in both rod and cone synaptic terminals suggested a reduced photoreceptor output to the inner retina. Retinal morphology of the P360 Igf1+/− mice showed only small alterations in the horizontal and bipolar cell processes, when compared with Igf1+/+ mice of matched age. Conclusions. In the mouse, IGF-I deficit causes an age-related visual loss, besides a congenital deafness. The present results support the use of the Igf1−/− mouse as a new model for the study of human syndromic deaf-blindness.

Environment and health with respect to a poverty-related disease: the epidemiology of trachoma in Spain, 1925-1941

Trachoma currently represents one of the three main causes of ‘avoidable' blindness and reaches intolerable dimensions in many developing countries. It was endemic in many regions of eastern Spain until well into the twentieth century. The aim of this paper is to analyze the epidemiological development of this disease in contemporary Spain; to examine its determining factors, particularly environmental and sanitary/health factors, and, finally, to study the health care, environmental and socio-economic measures that led to its control and eradication. We believe that the historical approach not only highlights the role of environmental factors in the development of trachoma, but may also aid in understanding the current epidemiology of trachoma.

Loss of Outer Retinal Neurons and Circuitry Alterations in the DBA/2J Mouse

Purpose. The DBA/2J mouse line develops essential iris atrophy, pigment dispersion, and glaucomatous age-related changes, including an increase of IOP, optic nerve atrophy, and retinal ganglion cell (RGC) death. The aim of this study was to evaluate possible morphological changes in the outer retina of the DBA/2J mouse concomitant with disease progression and aging, based on the reduction of both the a- and b-waves and photopic flicker ERGs in this mouse line. Methods. Vertically sectioned DBA/2J mice retinas were evaluated at 3, 8, and 16 months of age using photoreceptor, horizontal, and bipolar cell markers. Sixteen-month-old C57BL/6 mice retinas were used as controls. Results. The DBA/2J mice had outer retinal degeneration at all ages, with the most severe degeneration in the oldest retinas. At 3 months of age, the number of photoreceptor cells and the thickness of the OPL were reduced. In addition, there was a loss of horizontal and ON-bipolar cell processes. At 8 months of age, RGC degeneration occurred in patches, and in the outer retina overlying these patches, cone morphology was impaired with a reduction in size as well as loss of outer segments and growth of horizontal and bipolar cell processes into the outer nuclear layer. At 16 months of age, connectivity between photoreceptors and horizontal and bipolar cell processes overlying these patches was lost. Conclusions. Retinal degeneration in DBA/2J mice includes photoreceptor death, loss of bipolar and horizontal cell processes, and loss of synaptic contacts in an aging-dependent manner.

Bliss, Nathaniel, 1622-1654, autographed letter signed to John Winthrop; Springfield, Mass., 1 side (2 pages), 1652 December 21

Correspondence regarding an illness Bliss was suffering; he writes that the medicines Winthrop had given him were ineffective and he has been suffering fits. The letter, which was finished in an unknown hand, reports further symptoms had developed, including headache and blindness, and requests Winthrop again send instructions for taking the medicine he originally sent Bliss, and any other medicine he would recommend.

Abordagem multidisciplinar do glaucoma congénito primário : caso clínico

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Mutação rara do gene NDP em doente pediátrico

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Réadaptation et performance visuelle chez la personne hémianopsique : une étude de cas portant sur les saccades oculaires et le blindsight

But: La perte unilatérale du cortex visuel postérieur engendre une cécité corticale controlatérale à la lésion, qu’on appelle hémianopsie homonyme (HH). Celle-ci est notamment accompagnée de problèmes d’exploration visuelle dans l’hémichamp aveugle dus à des stratégies oculaires déficitaires, qui ont été la cible des thérapies de compensation. Or, cette perte de vision peut s’accompagner d’une perception visuelle inconsciente, appelée blindsight. Notre hypothèse propose que le blindsight soit médié par la voie rétino-colliculaire extrastriée, recrutant le colliculus supérieur (CS), une structure multisensorielle. Notre programme a pour objectif d’évaluer l’impact d’un entraînement multisensoriel (audiovisuel) sur la performance visuelle inconsciente des personnes hémianopsiques et les stratégies oculaires. Nous essayons, ainsi, de démontrer l’implication du CS dans le phénomène de blindsight et la pertinence de la technique de compensation multisensorielle comme thérapie de réadaptation. Méthode: Notre participante, ML, atteinte d’une HH droite a effectué un entraînement d’intégration audiovisuel pour une période de 10 jours. Nous avons évalué la performance visuelle en localisation et en détection ainsi que les stratégies oculaires selon trois comparaisons principales : (1) entre l’hémichamp normal et l’hémichamp aveugle; (2) entre la condition visuelle et les conditions audiovisuelles; (3) entre les sessions de pré-entraînement, post-entraînement et 3 mois post-entraînement. Résultats: Nous avons démontré que (1) les caractéristiques des saccades et des fixations sont déficitaires dans l’hémichamp aveugle; (2) les stratégies saccadiques diffèrent selon les excentricités et les conditions de stimulations; (3) une adaptation saccadique à long terme est possible dans l’hémichamp aveugle si l’on considère le bon cadre de référence; (4) l’amélioration des mouvements oculaires est liée au blindsight. Conclusion(s): L’entraînement multisensoriel conduit à une amélioration de la performance visuelle pour des cibles non perçues, tant en localisation qu’en détection, ce qui est possiblement induit par le développement de la performance oculomotrice.

The midwife in England, being a study in England of the working of the English Midwives act of 1902 /

At head of title: Prevention of blindness. no. 13.

Reflections of a lifetime reader : an address delivered by Carl R. Augusto to the Conference of Librarians Serving Blind and Physically Handicapped Individuals, Baltimore, Maryland, May 4, 1992.

Shipping list no.: 93-0073-P.

Publication.

Some volumes issued out of chronological sequence.

Analysis of certain cartoons of Raffaele.

Consists of articles issued separately, bound with handwritten table of contents.

Health inquiry : hearings before the Committee on Interstate and Foreign Commerce, House of Representatives, Eighty-third Congress, first-[second] session, on the causes, control, and remedies of the principal diseases of mankind.

Hearings held Oct. 1, 1953-Jan. 11, 1954.

The news letter on sight conservation.

Issues for 1915-27 published under the Society's earlier name: National Committee for the Prevention of Blindness.

Orientation and mobility for the visually handicapped : a guide for parents.

Cover title.

The census of Egypt taken in 1917 ...

English and Arabic.