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)

In 71 patients that underwent intracapsular extraction of the cataract it was possible to collect aqueous humor (a.h.) in sufficient quantities at the beginning and at the end of the operation. Using radial immunodiffusion albumin, IgG and alpha-1-antitrypsin were measured in the samples. In secondary a.h. huge variations in the concentrations were apparent. The primary permeability of the blood-aqueous barrier and the time between sampling had no influence on the relative increase of the proteins. No statistically significant difference was found between normotensives and hypertensives and patients with or without myopia of higher degree (over 6 diopters). The relative increase of proteins according to their difference in molecular weight followed the same pattern as described for anterior uveitis. In patients for whom an enzymatic zonulolysis with trypsin was used for the extraction, the relative increase of IgG was significantly smaller than in those that did not receive this treatment (P less than 0.005). The possible sources contributing to the formation of secondary a.h. are discussed.
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PMID:Immediate changes in protein-concentration in aqueous humor induced by intracapsular lens extraction in human eyes. 11 24

In an effort to elucidate the molecular changes which take place in the human lens with the onset of nuclear cataract, the urea-insoluble protein fraction, solubilized with dithiothreitol, was digested with trypsin. Tryptic peptides separated by HPLC, were examined by both mass spectrometry and Edman degradation. A pentapeptide Gly-Glu-Tyr-Pro-Arg which is contained within the beta-crystallin sequence was isolated. This finding provides direct evidence that beta-crystallin is present in the urea-insoluble protein fraction which is known to be characteristic of human nuclear cataract lenses.
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PMID:Direct approach to identification, at the molecular level, of modified proteins in human nuclear cataractous lenses: beta-crystallin is a component of the urea-insoluble protein fraction. 147 78

The senescence accelerated mouse (SAM) has recently been characterized as a unique model to investigate age-related disorders, including amyloidosis, cataract, osteoporosis and dementia. However, little is known as to the properties of the lung in these animals. Tobacco smoke is also associated with enhanced loss of elastic recoil and the development of emphysema. We have attempted to examine morphological as well as biochemical changes of the distal lung in SAM-P/2, as the senescence-prone series and SAM-R/1, as the senescence-resistant series. The animals were intermittently exposed to tobacco smoke or air by Hamburg II machines for 5 weeks. Then both groups of animals were killed for histologic and biochemical study. Compared with SAM-R/1, SAM-P/2, even with air exposure, showed a higher value of the mean linear intercept without alveolar wall destruction. It became even greater due to tobacco exposure with emphysematous change. Tobacco exposure accumulated inflammatory cells into alveoli in SAM-P/2, but not in SAM-R/1. Oxygen radical generation by those cells was also higher in SAM-P/2. Analysis of bronchoalveolar lavage fluid in SAM-P/2 after tobacco exposure disclosed increases in albumin content, total protein content and elastase-like activity. There were decreases in the ratio of elastase inhibitory capacity (EIC) to trypsin inhibitory capacity (TIC), contents of glutathione and total free thiol groups. Moreover, SAM-P/2 showed significantly lower EIC/TIC ratio in serum, even with air exposure, than that of SAM-R/1. These results indicate that SAM-P/2 can be a good model for the study of natural evolution of the aging lung as well as its susceptibility to tobacco smoke in the development of emphysema.
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PMID:A new murine model of aging lung: the senescence accelerated mouse (SAM)-P. 179 64

It has been suggested that proteases are involved in removal of damaged or obsolete proteins and/or that the activation of proteases could contribute to cataract formation. This review summarizes the properties of several recently studied lens endopeptidases including: trypsin-like protease, multicatalytic endopeptidase complex, membrane bound proteases, and calpain. Properties discussed include composition, substrate specificity, distribution, changes in activity during aging, and regulation. Additionally, properties of the lens ubiquitin conjugation system are reviewed. When possible, an attempt was made to relate these findings to whether the lens proteolytic activity was involved in clearing damaged proteins, or whether it could contribute to cataract formation. Clearing of damaged or obsolete lens proteins may involve the participation of several protease activities. Findings suggest that lens protease activities are lost at variable rates during aging, and differ in concentration between species. It was concluded that the consequence of proteolytic activity in the lens may depend closely on the compliment of proteolytic activities found. For instance, proteases causing only partial degradation of lens proteins may predominate in lenses undergoing cataract formation, while proteases assisting in the removal of partially degraded proteins are lost. The partially degraded lens proteins, as well as other denatured lens proteins, may then accumulate and lead to cataract formation.
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PMID:Role of proteolysis in lenses: a review. 256 21

One possible route to cataract formation may be via the carbamoylation of lens proteins due to increased concentrations of cyanate in the body resulting from uraemia associated with renal failure and with severe diarrhoea. Carbamoylation of gamma-II-crystallin, which is found in the lens core, could alter the surface charge network of the molecules, resulting in aggregation, increased light-scattering and hence cataract. We have attempted to locate the site(s) of carbamoylation in gamma-II-crystallin. gamma-II-Crystallin was isolated by gel chromatography and ion-exchange chromatography. gamma-II-Crystallin was then carbamoylated by incubation with potassium [14C]cyanate, followed by citraconylation and digestion with trypsin to give peptides that were separated by high-resolution ion-exchange chromatography. The amino acid compositions of the radioactive peptides were compared with the expected peptide composition for gamma-II-crystallin. The radioactive peptide compositions, which agreed with the theoretical peptides, all matched with the N-terminal region of gamma-II-crystallin and had in common the presence of the N-terminal glycine residue. It appears that the alpha-amino group of the N-terminal glycine was the main site of carbamoylation. This site forms part of the charge network on the surface of gamma-II-crystallin.
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PMID:Site of carbamoylation of bovine gamma-II-crystallin by potassium [14C]cyanate. 259 Jan 75

The addition of edetic acid (EDTA) or trypsin to the infusion during a simulated extracapsular cataract extraction on cadaver eyes facilitates the removal of lens epithelial cells from the anterior capsule. Modification of the chemical composition of infusions used during extracapsular surgery may maximise lens epithelial cell removal and hence reduce the incidence of opacification of the posterior capsule after cataract extraction.
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PMID:The human anterior lens capsule--an attempted chemical debridement of epithelial cells by ethylenediaminetetracetic acid (EDTA) and trypsin. 313 44

Trypsin inhibition (reduction in benzoyl arginine p-nitroanilide hydrolysis), elastase inhibition (reduction in succinyl trialanyl p-nitroanilide hydrolysis), and chymotrypsin inhibition (reduction in acetyl tyrosine ethyl ester hydrolysis) by neutral extracts of mammalian lenses were estimated. The activities were found to be markedly elevated in human cortical cataract lenses compared to normal adult lenses (antielastase 7.21 +/- 3.90 units (mean +/- SD) in cataract compared to 1.46 +/- 0.57 in normals; antitryptic, 0.54 +/- 0.38 and 0.12 +/- 0.04; antichymotryptic, 1.03 +/- 0.61 and 0.297 +/- 0.055). Antielastase activity was distinctly higher in adult normal human lenses compared to infant lenses (0.159 +/- 0.068). Elastase- and trypsin-like activities were detected at low levels in all mammalian lenses. Chymotrypsin-like activity could not be observed in the lenses. The cataractous lenses had lower trypsin- and elastase-like activities compared to normal human lenses (elastase 1.20 +/- 0.643 in normal compared to 0.062 +/- 0.035 in cataract; trypsin, 0.367 +/- 0.154 and 0.069 +/- 0.038). The role of protease: inhibitor complexes in the expression of the individual activities and their role in cataractogenesis are discussed.
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PMID:Proteases and protease inhibitory activities in normal mammalian lenses and human cataractous lenses. 351 55

Leakage of lens proteins from a hypermature cataract can result in a characteristic glaucoma that is associated with the invasion of the anterior chamber by monocytes. We hypothesized that the lens proteins themselves might account for the monocyte response. A sonicated lens induced concentration-dependent migration of monocytes in a Boyden chamber assay system. Checkerboard analysis indicated that the movement was directed rather than merely random. Relative to a control chemoattractant, N-formyl-methionyl-leucyl-phenylalanine, the lens induced monocyte migration more potently than neutrophil migration. The ability to induce migration was markedly reduced by incubating the lens with either trypsin or papain. Chemotactic activity was readily demonstrable in lenses from young donors without cataracts. Separation of lens proteins by gel filtration with high-performance liquid chromatography indicated that the chemotactic activity was most consistently associated with the gamma crystallin fraction. The chemotactic activity of lens proteins may contribute to the pathogenesis of phacolytic glaucoma or the uveitis resulting from retained cortical material after cataract extraction.
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PMID:Chemotactic activity of lens proteins and the pathogenesis of phacolytic glaucoma. 367 92

Spontaneously diabetic dogs were treated initially (the first 1/2 yr) with i.v. prostacyclin and oral aspirin and then for 1 yr with varying doses of aspirin alone. At this time cataracts prevented visualization of retinae, and one eye of each animal was removed for examination of the vasculature of the trypsin digested retinae. Studies of the blood during the course of treatment showed an elevation of plasma cyclic adenylic acid and marked lowering of inordinately high platelet count and platelet aggregation. Treatment was stopped and after an additional 1/2 year the animals were euthanized and the fellow eye removed for retinal study. Although just three diabetic animals survived for binocular retinal histology, there were no discernible differences in the retinal vasculature in the fellow eyes of a given animal, and in only one of these three animals were there clear signs of diabetic retinopathy. We must conclude, therefore, that in spite of relative normalization of platelet function in the parameters measured during the course of treatment, we cannot yet claim a salutary effect of treatment on the diabetic retina. Cataracts prevented us from having better information on diabetic retinae prior to treatment and a redesigned study would have to include unilateral histological retinal examination before any treatment is started to determine if, indeed, improved platelet physiology slows or reverses changes in the diabetic retina.
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PMID:Aspirin and prostacyclin treatment of diabetic dogs. 631 15

We studied 62 eyes submitted to the Armed Forces Institute of Pathology (AFIP) from 1958 through 1980 that satisfied our criteria for the histologic diagnosis of Coats' disease. Our histopathologic definition of Coats' disease was the presence of a primary vascular lesion consisting of retinal telangiectasia with leakage of plasma to form intraretinal and subretinal exudates. In the cases we reviewed, Coats' disease occurred more frequently in boys, it usually affected only one eye, and was generally detected in the first decade of life. In 52 cases (79%) the clinical manifestations, strabismus and leukokoria, were thought to be caused by retinoblastoma. Angle closure glaucoma was present in 36 cases (58%). In all but one of the cases studied, the lesion was located peripheral to the equator. We further identified diffuse involvement of capillaries in the peripheral retina using trypsin-digest preparations. Associated histologic findings included: rubeosis iridis, cataract, vitreous neovascularization, and nodules resulting from fibrous metaplasia of the retinal pigment epithelium. These fibrous nodules typically occurred in the macular area and occasionally contained calcium or bone.
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PMID:Coats' disease: a study of 62 histologically confirmed cases. 650 5


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