Diseases Commons^™

Genetic And Phenotypic Variations Of Inherited Retinal Diseases In Dogs: The Power Of Within- And Across-Breed Studies, Keiko Miyadera, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Considerable clinical and molecular variations have been known in retinal blinding diseases in man and also in dogs. Different forms of retinal diseases occur in specific breed(s) caused by mutations segregating within each isolated breeding population. While molecular studies to find genes and mutations underlying retinal diseases in dogs have benefited largely from the phenotypic and genetic uniformity within a breed, within- and across-breed variations have often played a key role in elucidating the molecular basis. The increasing knowledge of phenotypic, allelic, and genetic heterogeneities in canine retinal degeneration has shown that the overall picture is rather more complicated than …

Exploring Human/Animal Intersections: Converging Lines Of Evidence In Comparative Models Of Aging, John Q. Trojanowski, Joan C. Hendricks, Kathryn Jedrziewski, F. Brad Johnson, Kathryn E. Michel, Rebecka S. Hess, Michael P. Cancro, Margaret M. Sleeper, Robert Pignolo, Karen L. Teff, Gustavo D. Aguirre, Virginia Man-Yee Lee, Dennis F. Lawler, Allan I. Pack, Peter F. Davies

Gustavo D. Aguirre, VMD, PhD

At a symposium convened on March 8, 2007 by the Institute on Aging at the University of Pennsylvania, researchers from the University’s Schools of Medicine and Veterinary Medicine explored the convergence of aging research emerging from the two schools. Studies in human patients, animal models, and companion animals have revealed different but complementary aspects of the aging process, ranging from fundamental biologic aspects of aging to the treatment of age-related diseases, both experimentally and in clinical practice. Participants concluded that neither animal nor human research alone will provide answers to most questions about the aging process. Instead, an optimal translational …

Canine And Human Visual Cortex Intact And Responsive Despite Early Retinal Blindness From Rpe65 Mutation, Geoffrey K. Aguirre, András M. Komáromy, Artur V. Cideciyan, David H. Brainard, Tomas S. Aleman, Alejandro J. Roman, Brian B. Avants, James C. Gee, Marc Korczykowski, William W. Hauswirth, Gregory M. Acland, Gustavo D. Aguirre, Samuel G. Jacobson

Gustavo D. Aguirre, VMD, PhD

Background RPE65 is an essential molecule in the retinoid-visual cycle, and RPE65 gene mutations cause the congenital human blindness known as Leber congenital amaurosis (LCA). Somatic gene therapy delivered to the retina of blind dogs with an RPE65 mutation dramatically restores retinal physiology and has sparked international interest in human treatment trials for this incurable disease. An unanswered question is how the visual cortex responds after prolonged sensory deprivation from retinal dysfunction. We therefore studied the cortex of RPE65-mutant dogs before and after retinal gene therapy. Then, we inquired whether there is visual pathway integrity and responsivity in adult humans …

Diseases Of The Retinal Pigment Epithelium-Photoreceptor Complex In Nonrodent Animal Models, Gustavo D. Aguirre, Jharna Ray, Lawrence E. Stramm

Gustavo D. Aguirre, VMD, PhD

Book Overview: The retinal pigment epithelium is a critical tissue within the eye. It lies directly behind the retina, where it provides metabolic support to the photoreceptors and controls their local environment. As a result, the RPE is vital to retinal function, but also a site of aging and disease that cause dysfunction and visual loss. This book brings together comprehensive reviews of basic and clinical science concerning the RPE. It is organized to juxtapose chapters on RPE disease with chapters on the underlying pathophysiology. These include up-to-date accounts of growth factors, laser effects, proliferative vitreoretinopathy, Bruch's membrane pathology, as …

Cloning Of Canine Galactokinase (Galk1) And Evaluation As A Candidate Gene For Hereditary Cataracts In Labrador Retrievers, Duska J. Sidjanin, John L. Mcelwee, Brian Miller, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

We identified a pedigree of Labrador retrievers (LR) that develop hereditary cataracts between 6 and 18 months of age. In humans, galactokinase deficiency is an autosomal recessive disorder characterized by juvenile onset of cataracts.1 In order to evaluate GALK1 as a candidate gene, we cloned and sequenced the canine GALK1 gene and tested a single nucleotide polymorphism (SNP) in the gene for segregation with cataracts in the LR pedigree.

Age-Dependent Disease Expression Determines Remodeling Of The Retinal Mosaic In Carriers Of Rpgr Exon Orfn15 Mutations, William Beltran, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

PURPOSE. To characterize the retinal histopathology in carriers of X-linked progressive retinal atrophy (XLPRA1 and XLPRA2), two canine models of X-linked retinitis pigmentosa caused, respectively, by a stop and a frameshift mutation in RPGRORF15. METHODS. Retinas of XLPRA2 and XLPRA1 carriers of different ages were processed for morphologic evaluation, TUNEL assay, and immunohistochemistry. Cell-specific markers were used to examine retinal remodeling events. RESULTS. A mosaic pattern composed of patches of diseased and normal retina was first detected in XLPRA2 carriers at 4.9 weeks of age. A peak of photoreceptor cell death led to focal rod loss; however, in these patches …

Calcium Channel Blocker D-Cis-Diltiazem Does Not Slow Retinal Degeneration In The Pde6b Mutant Rcd1 Canine Model Of Retinitis Pigmentosa, Susan E. Pearce-Kelling, Tomas S. Aleman, Amanda Nickle, Alan M. Laties, Gustavo D. Aguirre, Samuel G. Jacobson, Gregory M. Acland

Gustavo D. Aguirre, VMD, PhD

Purpose: D-cis-diltiazem, a calcium channel blocker, has been reported to enhance photoreceptor survival in the rd mouse, a model of retinitis pigmentosa (RP) resulting from mutation of the PDE6B gene. We tested the hypothesis that diltiazem treatment would similarly rescue the canine rcd1 model of RP, which is also caused by a null mutation in the PDE6B gene. Methods: D-cis-diltiazem was delivered orally twice daily to rcd1 affected dogs beginning at 4 weeks of age; untreated age-matched rcd1 dogs served as controls. At 14 weeks, electroretinograms (ERG) were performed on all animals; 14 dogs were euthanized at this age, and …

Blinded By The Light: Retinal Phototoxicity In The Context Of Safety Studies, Maria Cristina De Vera Mudry, Sven Kronenberg, Shun-Ichiro Komatsu, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

No abstract provided.

Canine Multifocal Retinopathy In The Australian Shepherd: A Case Report, Ingo Hoffmann, Karina E. Guziewicz, Barbara Zangerl, Gustavo D. Aguirre, Christian Y. Mardin

Gustavo D. Aguirre, VMD, PhD

A 1-year-old Australian Shepherd (AS) was presented for a routine hereditary eye examination. During the examination multiple raised, brown to orange lesions were noted in the fundus, which could not be attributed to a known retinal disease in this breed. As they clinically most closely resembled canine multifocal retinopathy (cmr) and no indication of an acquired condition was found, genetic tests for BEST1 gene mutations were performed. These showed the dog to be homozygous for the cmr1 (C73T/R25X) gene defect. Furthermore, ultrasound (US), electroretinography (ERG), and optical coherence tomography were performed, confirming changes typical for cmr. Subsequently, the AS pedigree …

Animal Model Of Human Disease: Mucopolysaccharidosis Type Vii (Sly Syndrome). Beta-Glucuronidase-Deficient Mucopolysaccharidosis In The Dog, Mark E. Haskins, Gustavo D. Aguirre, Peter F. Jezyk, Edward H. Schuchman, Robert J. Desnick, Donald F. Patterson

Gustavo D. Aguirre, VMD, PhD

No abstract provided.

A Naturally Occurring Mutation Of The Opsin Gene (T4r) In Dogs Affects Glycosylation And Stability Of The G Protein-Coupled Receptor, Li Zhu, Geeng-Fu Jang, Beata Jastrzebska, Slawomir Filipek, Susan E. Pearce-Kelling, Gustavo D. Aguirre, Ronald E. Stenkamp, Gregory M. Acland, Krzysztof Palczewski

Gustavo D. Aguirre, VMD, PhD

Rho (rhodopsin; opsin plus 11-cis-retinal) is a prototypical G protein-coupled receptor responsible for the capture of a photon in retinal photoreceptor cells. A large number of mutations in the opsin gene associated with autosomal dominant retinitis pigmentosa have been identified. The naturally occurring T4R opsin mutation in the English mastiff dog leads to a progressive retinal degeneration that closely resembles human retinitis pigmentosa caused by the T4K mutation in the opsin gene. Using genetic approaches and biochemical assays, we explored the properties of the T4R mutant protein. Employing immunoaffinity-purified Rho from affected RHO^T4R/T4R dog retina, we found …

Rpgrip1 And Cone-Rod Dystrophy In Dogs, Tatyana N. Kuznetsova, Barbara Zangerl, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Cone–rod dystrophies (crd) represent a group of progressive inherited blinding diseases characterized by primary dysfunction and loss of cone photoreceptors accompanying or preceding rod death. Recessive crd type 1 was described in dogs associated with an RPGRIP1 exon 2 mutation, but with lack of complete concordance between genotype and phenotype. This review highlights role of the RPGRIP1, a component of complex protein networks, and its function in the primary cilium, and discusses the potential mechanisms of genotype–phenotype discordance observed in dogs with the RPGRIP1 mutation.

Echinococcus Multilocularis In Foxes And Raccoon Dogs: An Increasing Concern For Baltic Countries, Guna Bagrade, Gunita Deksne, Zanda Ozoliņa, Samantha Jane Howlett, Maria Interisano, Adriano Casulli, Edoardo Pozio

Harold W. Manter Laboratory: Library Materials

Background

In Europe, the life cycle of Echinococcus multilocularis is predominantly sylvatic, involving red foxes (Vulpes vulpes) as the main definitive hosts and rodents such as muskrats and arvicolids as intermediate hosts. The parasite is the etiological agent of human alveolar echinococcosis, a malignant zoonotic disease caused by the accidental ingestion of eggs shed by definitive hosts in their feces. The aims of this study were to investigate the prevalence of E. multilocularis in red foxes and raccoon dogs (Nyctereutes procyonoides) and to study the environmental factors favoring the perpetuation of the parasite in Latvia. …