Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A unified theory of growth and age-dependent disorders is applied to the interpretation of epidemiological data for natural and radiation-induced cataracts and natural macular degeneration in man. Using the same unified theory, mechanisms are also proposed to explain the experimental evidence for natural and radiation-induced lenticular opacities in the lens of the mouse. Epidemiological and experimental data are strikingly consistent with the hypothesis that natural cataract formation is an autoaggressive process but the details of pathogenesis differ greatly between the two species. Radiation dose-response relations reflect these contrasts. Lenticular opacities in the nuclear-bomb survivors at Hiroshima and Nagasaki were probably induced by a 'single-track' mechanism. Radiation-induced generalised opacification in the lens of the mouse results from a 'multi-track' process. The pathogenesis of natural macular degeneration in man happens to have close parallels with that of natural opacification in the mouse. We discuss some implications of these inferences for the phenomenon of radiation-induced lethal disorders in man.
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PMID:Natural and radiation-induced cataracts in man and mouse, and natural macular degeneration in man: proposed mechanisms. 404 73

130 human lens impaired with cataract of various etiology (senile, traumatic, complicated cataract) and of different cataract maturation (initial, immature, quite mature, mature, over-maturated) as well as 18 transparent lens were studied. Primary products of lipid peroxidation (LP, hydroperoxides), secondary products (ketodiens) and the end products (Shiff bases) were distinctly accumulated in cataract lens. Intermediates of primary LP products were accumulated in lens within early periods of cataract development but the end LP products were mainly found at the late steps of cataract formation. Accumulation of the LP products was not distinctly different in cataracts with various clinical manifestations but similar in the level of maturation, thus indicating that lipid peroxidation plays a universal role in the process of lens opacity. The data obtained suggest that inhibitors of free radical oxidation (antioxidants) may be employed in medicamental treatment of cataracts.
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PMID:[Accumulation of lipid peroxidation products in the human lens during cataract maturation]. 409 Mar 73

The study was undertaken to determine if occupational exposure to infrared (IR) radiation increases the risk of developing cataract. The study includes epidemiologic investigations of two groups of workers exposed to IR radiation and two groups of non IR-exposed controls. The first investigation included 208 iron and steel workers and 208 controls. For each of the workers, the lifetime IR-exposure was calculated with the help of occupational interviews and measurements of the IR-exposure to their eyes in their jobs. Eye examinations including a detailed slit lamp examination of the lens were made. Exposed persons and controls were examined randomly. Wedge shaped opacities, a common type of senile lens opacity, were found in 32% of IR-exposed workers 60 years and older and in 12% of controls of the same age. In younger age groups there was no significant difference between exposed and controls regarding the presence of lens opacities. The second investigation included 209 IR-exposed glass workers and 298 controls. Workers over 50 years of age and with at least 20 years of occupational IR-exposure were included. Special care was taken to include retired workers. Exposure determinations and ophthalmological examinations were made in the same way as in the first study. The eye examinations of the glass workers showed that 16% of glass workers over 70 years of age had been operated for cataract compared to 1% of controls of the same age. In neither of the two studies was it possible to detect a dose-effect correlation. The exposure measurements showed that the maximal doses in both the iron and the glass industry are about the same. There are, however, a large number of jobs in the iron and steel industry that give low doses while most jobs in the glass works give high exposures. Cataract was found to be more common in the left than in the right eye. Measurements of the exposure to the two eyes separately also showed that the left eye in some working moments is exposed to higher irradiances than the right. A family history of cataract was found to increase the risk for the development of cataract in glass workers.
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PMID:Infrared radiation and cataract. 609 98

Particular glaucoma drug hazards for cataract patients include miosis, exacerbation of lens opacity, pupillary block, and the development of systemic adrenergic or cholinergic adverse drug effects or interaction. Each available antiglaucoma drug needs to be selected in individual cases with the knowledge of side effects that are likely to develop. For the glaucoma-cataract patient, a glaucoma regimen need be designed to minimize visual impairment, to minimize exacerbation of cataract, and to prevent introduction of new ocular disorders. At the time of cataract surgery, the regimen should be reassessed to maximize a smooth operative course and minimize systemic operative and anesthetic complications.
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PMID:Hazards of medical glaucoma therapy in the cataract patient. 612 71

A new procedure for neovascular glaucoma that has reduced intraocular pressure (IOP) significantly and has caused relatively few postoperative complications is introduced. Aqueous is shunted to the reservoir of an encircling no. 20 silicone band from which fluid is postulated to diffuse into the orbit. The anterior chamber tube shunt to an encircling band (ACTSEB) procedure was conducted in 19 eyes with neovascular glaucoma. After surgery 18 of the 19 eyes (95%) followed for periods ranging between five and 26 months (mean: 59 weeks) had controlled IOP using less than or equal to 20 mm Hg as normal, and one eye had partial control (eye 9) at 26 mm Hg. Despite the preoperative use of atropine sulfate, timolol maleate, acetazolamide, and 20% mannitol, the patients' average preoperative IOP was 54.1 mm Hg. After surgery the average IOP fell, dramatically, to 16.2 mm Hg. The mean change in IOP was 37.9 +/- 9.8 (SD). This change is statistically significant by the paired t-test, P less than 0.01. Minimal postoperative medications were required for pressure control. Postoperative complications included hyphema (21%), prolonged flat chamber (74%), localized peripheral lens opacity (5%), localized corneal opacity (5%), and possible acceleration of progressive cataract formation (25%). Results of current surgical procedures used to manage neovascular glaucoma are compared to the ACTSEB results.
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PMID:Anterior chamber tube shunt to an encircling band in the treatment of neovascular glaucoma. 618

Favor, in the Appendix to a paper by Ehling and his collaborators (Ehling et al., 1982), develops a method that tests for the presence of a partially penetrant dominant cataract mutation in a suspected parent (showing lens opacity) outcrossed to a homozygous strain-101 mouse when no individual with lens opacity is observed in the progeny. This method, based on the Chi-square distribution, is examined as to the validity of the Normal approximation. An alternative procedure is discussed.
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PMID:Testing for the presence of a partially penetrant dominant gene. 633 69

The aim of the presented study was to establish if occupational exposure to infrared (IR) radiation increases the risk of developing cataract, and to correlate the lens findings to the degree of exposure. The eyes of 208 IR-exposed workers and 208 controls, all from 6 Swedish iron and steel manufacturing plants, were examined. An increased prevalence of wedge-shaped opacities was found in IR-exposed persons 60 years of age and older. This type of lens opacity is normally considered to be a purely senile change. Acceleration of senile changes by IR radiation is suggested. Stratification of the material with regard to exposure was made on different grounds, but failed to show a dose-effect-correlation.
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PMID:Infrared radiation and cataract. I. Epidemiologic investigation of iron- and steel-workers. 652 21

A patient with diabetic retinopathy and senile anterior cortical and nuclear cataract was treated with argon laser photocoagulation of the fundus. During the treatment, white ovoid opacities appeared in the lens cortex, extending into the nucleus. They remained nonprogressive for five weeks, when cataract extraction was performed. The lens was studied by light and electron microscopy. The lenticular opacities contained rows of damaged, spindle-shaped lens fibers, with laminated cellular debris and clear spaces. We compared the unique features of the laser-induced lenticular lesions with the senile cataractous changes in the same crystalline lens.
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PMID:Argon laser-induced cataract. A clinicopathologic study. 670 16

Light and electron microscopy and slitlamp microscopy were used to follow the development and partial repair of injury-induced cataract in the lens of the pigmented eye of the grey squirrel. These processes proceed in much the same way as in previously-studied albino rodents and rabbits in spite of invasion of the lens opacity by pigmented cells in the squirrel eye. Epithelial and capsular regeneration and lens fiber repair occur rapidly and apparently independently from the accumulation of pigmented cells, fibroblasts and collagen in the wound outside the lens epithelial layer. Using morphological criteria, some of the pigmented cells in the lens wound are identified as iris stromal melanocytes and pigmented epithelial cells; this is consonant with the slitlamp observations of streams of pigmented cells extending from the iris to the lens wound. The role, if any, of the pigmented cells in lens wound healing is unknown.
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PMID:Lens wound healing and cataractogenesis in a pigmented eye. 672 6

Age-related changes in the lenses of ddy strain mice, ranging from 4 to 24 months old, were studied histologically. The early change of aging lens was noted as a slight extension of fiber cells into the posterior capsule in the area behind the nuclear bow around 6 months of age. Those cell extensions formed villous projections reaching up to one half of the total capsule by 18 months of age. Another notable change was a decreasing cell population of the lens epithelium and the appearance of their nuclear inclusions. The latter contained rough endoplasmic reticulum, free ribosomes and filamentous matrix at the early stage and a mass of filamentous material at the later stage. This change was initiated by 12 months of age, and became profound with the increase of age. Moreover, the bow nuclei became markedly displaced posteriorly after 14 months of age. At about 18 months of age, when the pathological changes in both epithelial and bow regions became severe, the superficial cells in the posterior cortex showed swelling and atrophy, which soon led to the lens opacity due to accumulation of cell debris and fluid. These histopathological changes associated with aging appear to correspond to the incipient form of posterior subcapsular cataract which is detectable by clinical examinations.
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PMID:Morphological study of age-related changes in mouse lens. 685 9


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