Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An Afrikaner kindred in South Africa had a dominantly inherited skeletal dysplasia-blindness-deafness syndrome. The affected individuals had reduced stature and a round, flattened facies. The bone changes resembled multiple epiphyseal dysplasia with additional minor abnormalities in the phalanges, femoral heads and spine. Progressive myopia, retinal thinning and crenated cataracts led to visual disturbance, while conductive deafness represented the third component of the triad. The syndromic significance of associated asteroid hyalosis is uncertain.
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PMID:Dominant inheritance of multiple epiphyseal dysplasia, myopia and deafness. 69 54

Onchocerciasis is a major cause of blindness worldwide, and much of the blindness is caused by onchocercal chorioretinitis. In an experimental animal model for ocular onchocerciasis, intravitreal injections of 10,000 live Onchocerca volvulus microfilariae isolated from infected humans into the eyes of cynomolgus monkeys (Macaca fascicularis) resulted in patchy, progressive loss of retinal pigment with pigment clumping. Areas of pigment loss were less extensive in animals that had been sensitized with microfilariae. Intravitreal injections of dead O. volvulus microfilariae resulted in mild vitritis with relatively less clinical change noted in the retina and choroid. Histopathologic examination revealed thinning and loss of outer retinal layers with pigment migration into the retina, and inflammation was more pronounced in eyes that received live microfilariae. Clinical changes appeared in eyes receiving live microfilariae before the development of significant antibody or cell-mediated immune responses. O. volvulus microfilariae appear to be more suitable than O. lienalis microfilariae in producing lesions which resemble human onchocerciasis in the primate model.
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PMID:Experimental ocular onchocerciasis in cynomolgus monkeys. IV. Chorioretinitis elicited by Onchocerca volvulus microfilariae. 201 31

Pathological changes in the retinal pigment epithelium (RPE) in a strain of chickens having hereditary blindness and retinal degeneration were described at the ultrastructural level. Photoreceptors in the retinal degenerate (rd) chicken had previously been noted to degenerate within a week after hatching. Affected chicks have neural retinas that are morphologically comparable to normal animals prior to that time despite an obvious lack of vision. In the present study, no pathological changes were noted in rd RPE prior to the time of photoreceptor degeneration. However, while mitochondria in the normal chick's RPE underwent diurnal changes in morphology within a few days of hatching, pleomorphic or ring mitochondria were not seen with high frequency in the rd chick. After photoreceptors began degenerating, changes were seen in the rd RPE. By 2 weeks of age, we noted a reduction in the depth and number of basal infoldings, an increase in number and size of autophagic vacuoles and large whorls of membranous material within rd RPE cells. Membranous debris and what appeared to be broken off outer segments were seen in the subretinal space at that time. These phenomena became more prominent and prevalent with time. In 3-4 week old specimens, nearly intact outer segments were seen within RPE cytoplasm. At the same time very few intact outer segments were present on photoreceptors. After this time degenerative changes were seen in the RPE: a thinning of cells (apical to basal cell width), spreading out of cells (increased distance between intercellular junctional complexes), hypopigmentation of cells and presence of free cells in the sub-retinal space. Some RPE cells appeared in a rounded up configuration, bulging into the subretinal space and making junctional complexes with remaining photoreceptor inner segments or Mueller cell processes. Many RPE cells did appear to maintain their phagocytic abilities, as evidenced by presence of many microvilli and pinocytotic vacuoles in the apical cytoplasm.
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PMID:Ultrastructural changes in the retinal pigment epithelium of congenitally blind chickens. 406 26

Hereditary blindness in Rhode Island Red chickens was analyzed at various post-hatching stages by light microscopy and electrophysiological recordings. At the time of hatching the retina of affected chicks appeared morphologically normal and identical to that of control, non-affected chicks. Whereas the electroretinographic (ERG) response to light stimulus in normal chicks was near the adult level at the time of hatching, no ERG either under light- or dark-adapted conditions was measurable in affected chicks at any stage examined. Photoreceptor cells of affected animals were seen to undergo degenerative changes after about one week post-hatching. Decrease in number of outer segments, spaces between inner segments and large spaces in the outer nuclear layer were apparent by Day 10. By Day 21, most of the photoreceptor inner segments appeared swollen, and the decrease in number of outer segments and photoreceptor nuclei was noteworthy. By the end of the second month no outer segments were seen and the majority of identifiable inner segments were from cones, a larger proportion than normally present being double cones. By six months, very few photoreceptor inner segments and nuclei remained; most inner segments were deformed and diminutive but usually contained a clearstaining oil droplet characteristic of the principal member of the double cone. In all stages after one week of age, pycnotic nuclei and thinning of inner retinal layers accompanied photoreceptor degeneration. In all specimens examined, degeneration of retinal cells was more pronounced in the superior central retina than in the periphery. Pathological changes were frequently also noted in the pigment epithelium overlying degenerating retina. Because the chick retina is well developed at birth, contains a fovea and a significant cone population and because cones (particularly one specific type) survive rods, we believe that this congenitally-blind chicken may be a useful model for studies on human hereditary retinal degenerations.
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PMID:Hereditary retinal degeneration in the Rhode Island Red chicken. I. Histology and ERG. 648 67

A rare case of Kufs' disease with retinal lesions is reported in which the first symptom of visual disturbances later resulted in total blindness. Various neurologic symptoms and mental deterioration also developed. The total duration of the illness was 32 years. Neuropathologic examination showed extensive ballooned nerve cells filled with lipopigments in the CNS. In the retina there was a thinning with severe loss of rods, cones, and outer nuclear and outer plexiform layers. The remaining ganglion cells of the retina were also ballooned and accumulated with lipopigments. Histochemical and electron microscopic examinations disclosed that the lipopigments in the ballooned neurons of the CNS and the retina were identical with lipofuscin pigments.
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PMID:Adult type of neuronal ceroid-lipofuscinosis with retinal involvement. 651 85

Trachoma is a leading cause of preventable blindness worldwide. The disease is caused by an intracellular epithelial gram-negative bacterium, Chlamydia trachomatis. The presence of children, overcrowding, and the lack of water in the household are factors that predispose to the transmission of the disease. The disease may remain asymptomatic but some patients many complain of redness, irritation, and ocular discharge. The principal initial clinical manifestation is a follicular conjunctivitis that may lead to conjunctival scarring, entropion, trichiasis, corneal thinning, and ulceration. Some patients develop corneal scars that lead to loss of vision. Despite the remarkable progress in our understanding of Chlamydial infections, the basic mechanisms involved in tissue damage and scarring remain to be elucidated. There are several effective therapeutic modalities for trachoma. Azithromycin oral single dose was found to be safe and effective in children with active trachoma. Conjunctival biopsy specimens obtained from adult patients receiving a single oral dose of azithromycin showed sustained high levels of azithromycin (above MIC of chlamydia) for up to 2 weeks after intake. These prolonged high levels of azithromycin in the conjunctival tissue following a single oral dose makes the drug suitable for the treatment of endemic trachoma.
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PMID:Trachoma: a review. 1143 24

Chicken pox is a very common infectious disease in children. Its corneal involvement is less serious than with measles, which may lead to blindness in numerous developing countries. However, with occasional cases occur. A case of a 59-year-old male patient whose left cornea was involved during a chicken pox infection at the age of 7 is reported. More recently, the vision of the right eye was normal at 20/20 and reduced to visual perception in the affected left eye. Corneal sensitivity was maintained in the left eye, which, however exhibited a central epithelial defect. A central round opacity of the left corneal stroma was believed to be the scar resulting from a previous disciform keratitis. The left central cornea was thinned and there was neither an anterior chamber flare nor new corneal vessels. This corneal condition required a corneal allograft, performed quickly because of the potential risk of perforation. Histopathological study of the corneal button showed a central corneal thinning with an increase in epithelial thickness. The corneal stroma was disorganized, with irregular collagen bundles. No inflammatory cells could be observed, however. All the histopathological changes observed were those of a corneal scar.
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PMID:[Followup of chicken pox keratitis. Anatomic-clinical case report]. 1239 39

Glaucoma is a leading cause of irreversible blindness in the world. Currently, glaucoma is diagnosed as a progressive optic neuropathy with characteristic optic disc and nerve fiber layer damage, usually associated with loss of visual function. The intraocular pressure (IOP) is the most important risk factor for the disease, although a significant proportion of patients do not have elevated IOP. Other risk factors include older age, African descent, myopia and family history of the disease. The ophthalmoscopic examination of the optic disc is essential to identify the signs of glaucomatous optic neuropathy, such as increased cupping, neuroretinal rim thinning or optic disc hemorrhages. Glaucomatous visual field loss usually starts in the periphery, and loss of central vision does not occur until late in the course of the disease. Visual function is most commonly assessed by standard automated perimetry; however, as many as 50% of nerve fibers can be lost before the appearance of visual field defects in this test. Newer technologies have been developed to find more sensitive ways to detect early glaucoma using both functional (short-wavelength automated perimetry and frequency-doubling perimetry) and structural (scanning laser topography, optical coherence tomography and scanning laser polarimetry) measurements. The management of glaucoma is based on lowering the intraocular pressure to prevent further optic nerve damage. Currently, there are five major classes of medications that are used to lower the intraocular pressure: Beta-adrenergic antagonists, adrenergic agonists, parasympathomimetics, prostaglandin-like analogues and carbonic anhydrase inhibitors. The goal of therapy is to maintain adequate vision for patients during their lifetime, keeping in mind the possible adverse effects of the drugs. If additional lowering of IOP is indicated or if medication fails to sufficiently lower the IOP, laser trabeculoplasty is usually the next step. If IOP is still not adequately controlled, incisional glaucoma surgery is indicated. Neuroprotective agents, which directly protect the optic nerve in glaucoma, are being evaluated in clinical trials.
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PMID:Medical backgrounders: glaucoma. 1258 21

In this 21 st century, it is predicted that blindness caused by corneal disorders which are difficult to prevent or treat will increase. It is important to study the pathogenesis, prevention, and treatment of these corneal disorders. Two corneal disorders, keratoconus and corneal dystrophy, were investigated to elucidate the pathogenesis by using molecular biological or molecular genetic techniques. Corneal transplantation is performed to restore vision of patients with corneal disorders, but the condition of the donor corneal endothelium is the key to maintaining transparency of the grafted cornea. We investigated the function or cell cycle mechanism of corneal endothelium at the level of the gene, and we also studied induced genes of endothelial cells during preservation of donor corneas. 1. Keratoconus: We searched for keratoconus patients with questionnaires sent to 141 hospitals in the 23 Wards of Tokyo. The incidence of patients was estimated to be 12.4 x 10(-5) for males and 6.7 x 10(-5) for females. The male/female ratio was 1.7: 1.0. The number of male patients was low when compared with studies reported 17 years ago. Rupture of Descemet's membrane in males was significantly higher than in females. Genesis of incidence: Apoptosis-related gene expression in thinning of the cornea was analyzed with cDNA microarrays, using mRNA isolated from cultured keratocytes of normal human corneas and keratoconus corneas. The expression of tumor necrosis factor alpha-induced protein 6(TNFAIP 6) was more enhanced, while insulin growth factor binding protein 5(IGFBP 5) was less expressed in keratoconus patients. 2. Corneal dystrophy: In corneal dystrophy related to four candidate genes such as transforming growth factor beta-induced(TGFBI) gene, membrane component 1 surface maker 1(M 1 S 1) gene, carbohydrate sulfotransferase gene 6(CHST 6), and collagen type VIII alpha-2(COL8 A 2) gene, 208 Japanese and 42 Vietnamese families were analyzed for the gene mutation and studied for the frequency of gene mutation and differences of clinical features. About 80% of Japanese with corneal dystrophies had mutation of the TGFBI gene and about 70% of them had Avellino corneal dystrophy. However, in Vietnamese patients, mutations were found in both the TGFBI gene (lattice corneal dystrophy; the phenotype gene was His 626 Arg) and in the CHST gene. The difference in frequency in gene mutations was significant between the two nationalities. Moreover, a novel corneal dystrophy associated with Asp 123 His mutation in TGFBI gene was found in one Vietnamese family. 3. Corneal endothelial cell: 1) gene expression: We performed random sequence and homology research analysis of 1,000 clones from a rabbit corneal endothelial cDNA library. Forty-five genes, including collagen type VIII alpha-1, were listed for the frequently observed cDNA in the library. 2) gene transfection: One of the causes of a growth-arrested state in human corneal endothelium was thought to be the presence of transforming growth factor-beta (TGF-beta) in aqueous humor. The transfection of Smad 7 gene, which blocks the signal, showed proliferation of the endothelial cells in the presence of aqueous humor. This suggests that there may be a possible practical application for using gene transfection with a non-viral DNA vector or with an adenovirus vector.
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PMID:[The pathogenesis and treatment of corneal disorders]. 1261 Aug 36

The purpose of the study reported here was to characterize the clinical aspects of the autosomal recessive retinopathy, globe enlarged (rge) phenotype in chicks (Gallus gallus). Rge/rge, rge/+ and +/+ chicks were studied from hatch to 336 days of age by general clinical examination, post-mortem examination, vision testing with an optokinetic device, ophthalmoscopy, biomicroscopy, tonometry, central corneal pachymetry, a-mode ultrasonography, infrared photoretinoscopy and photokeratometry. Additionally, preliminary electroretinographic and histopathologic investigations were performed. There is a variable degree of vision loss in rge/rge chicks at 1 day of age with further chicks losing vision over the next few weeks until all chicks become functionally blind by 30 days of age (although some optokinetic responses remain in some of the rge/rge chicks). Over the first few weeks of life rge/rge chicks develop thicker corneas with a larger radius, hyperopia, shallower anterior chambers and enlarged globes both radially and axially, compared to controls. A preliminary ERG study showed that 1 day old rge/rge chicks have an elevated response threshold, a lower amplitude a-wave with a markedly shallow leading slope, a lack of both oscillatory responses and c-waves and, at brighter flashes, an increased b-wave amplitude. Light microscopy revealed no gross retinal abnormalities in young chicks to account for the blindness. A thinning of all retinal layers developed in parallel with globe enlargement. The rge defect is a unique progressive retinal dystrophy that results in a severe visual deficit, abnormal electroretinographic waveforms, and secondary globe enlargement.
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PMID:Clinical features of the retinopathy, globe enlarged (rge) chick phenotype. 1284 54


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