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)

Three districts in the Punjab plains were surveyed in 1976-7 for senile cataract and potential risk factors. The prevalence of senile cataract was 15.3% among 1269 persons examined who were aged 30 ang older, and 4.3% for all ages. These figures confirmed previous reports of high prevalence. The prevalence was 1% for ages 30-49 and increased markedly in the sixth and seventh decades to 67% for ages 70 and older. Univariate age-adjusted analyses of selected socioeconomic, demographic, dietary, and other variables suggested that a higher prevalence was associated with being widowed, low education, use of rock salt in cooking, infrequent consumption of various protein foods (beans and lentils, milk, eggs, and curd), short height, and low weight. Multivariate analysis further suggested low total protein consumption as a risk factor that may account for as much as 40% of the excess prevalence of Punjab cataract over that in a US population study.
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PMID:Prevalence and aetiology of cataract in Punjab. 705 41

We investigated histologically the effect of postoperative intraocular pressure (IOP) on wound sealing after self-sealing cataract surgery in rabbits. A scleral pocket and internal corneal flap were made according to Ernest's method, and phacoemulsification was performed. Balanced salt solution was injected to self-seal the wound and to raise the IOP to 30 mmHg (high IOP group), to raise the IOP to 30 mmHg and then lower it to 15 mmHg (high-low IOP group), or to raise the IOP to only 15 mmHg (low IOP group). After various days, the eyes were analyzed by corneal topography and enucleated. The corneoscleral tissues were examined histologically. The wound adaptation was good in the high IOP group and the high-low IOP group on the external and internal sides on the first day after operation, but the wound adhesion was poor in the low IOP group even on the fourth day and became attached on the seventh day. We suggest that the difference of wound sealing caused by different postoperative IOPs might affect early postoperative astigmatism.
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PMID:[Corneoscleral wound healing after self-sealing cataract surgery--3. Effect of postoperative intraocular pressure on wound sealing]. 766 Oct 39

Cataract development has been reported in Dahl salt-sensitive (DS) hypertensive rats with high-salt intake. An alteration in ionic transport and electrolyte balance has been reported to be associated with hypertension in these animals. A morphological evaluation of the lenses of salt-sensitive 'cataract-prone' (DS) and salt-resistant (DR) control animals is lacking. We undertook this investigation to evaluate changes in lenticular morphology and in systolic blood pressure (SBP) following administration of high-salt. Both DS and DR rats were given high-salt for up to 33 weeks. Lenses were extracted at desired intervals following the initiation of the high-salt diet and processed for light and transmission electron microscopy. Except for some variations between animals, our study showed that DR rats, in general, exhibited normal SBP and relatively normal morphology. In comparison, the lenses of DS hypertensive rats demonstrated the following major changes: (1) some epithelial cells showed multilayering, nodule formation, pyknotic nuclei, swelling of cell organelles, presence of a large number of lysosomes, and distension of intercellular spaces, (2) disorganization of the bow and (3) swelling of fiber cells in the equatorial region. These changes were similar to those observed in precataractous stages during the development of several types of experimentally induced cataracts and indicate an alteration in normal electrolyte balance as well as hyperosmolarity. Changes in ion transport and electrolyte imbalance have been reported in the lenses of DS rats on high-salt diet. These alterations and a defect in the sodium-potassium pump may be responsible for cataract development in these hypertensive rats.
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PMID:Lenticular alterations in hypertensive rats. 769 59

Calf lens alpha-crystallin was isolated and the lysine residues were extensively modified with a variety of chemical agents. The effect of these modifications on elastase inhibitor activity, apparent molecular size, antibody reactivity and solubility were determined. The addition of either a methyl group or a threose residue did not alter the charge on the lysine residues and had little or no effect on either inhibitor activity or apparent molecular size. The introduction of a negative charge by either carboxymethylation or citraconylation caused a marked decrease in size and an almost complete loss of inhibitor activity. The introduction of a hydrophobic residue by reaction with either a trinitrobenzenesulfonic acid or Bolton Hunter reagent caused a slight increase in size, but a 70% increase in elastase inhibitor activity. Reaction with fluorescamine resulted in the dissociation of alpha-crystallin in a 200-kDa species, yet caused a two to four-fold increase in elastase inhibitor activity, which was similar to the activity of the water-insoluble fraction isolated from aged human lens and cataract. Several of these modified alpha-crystallins were compared for reactivity with a polyclonal alpha-crystallin antiserum using a quantitative slot blot assay. Charge neutral modifications resulted in a two to three-fold loss of antibody recognition, whereas the other preparations showed an almost complete loss of antigenic activity. None of the modifications caused the alpha-crystallin to precipitate at higher salt concentrations (0.3 M) with the exception of threose which caused a 30% decrease in soluble protein.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Chemical modification of alpha crystallin. 843 30

Bendazac has been used as an anti-cataractogenic drug. It has been reported that this acts by preventing protein denaturation. In this study the ability of bendazac to inhibit in vitro glycation of human lens crystallins was evaluated. Possible effects of bendazac were detected by incubation of WS crystallins with the reducing sugars glucose and fructose. The efficiency of bendazac was evaluated by means of selected parameters including: browning, glycation (measured as tyrosine content) and specific NTP-fluorescence. The results showed clearly that bendazac (bendazac L-lysine and sodium) inhibits the early stages of protein glycation, as well as the formation of fluorescent advanced glycation products. Bendazac lysine (20 mM) proved to be more effective in inhibiting fluorescence development (67% inhibition) that the corresponding sodium salt (35% inhibition). No significant differences were found with respect to furosine levels; about 40% inhibition was produced with either bendazac lysine or sodium salt bendazac clearly inhibits glycation of human lens crystallins, as can be efficiently monitored by following specific changes in lens protein fluorescence. These results may constitute a new and relevant therapeutic approach to monitoring cataract development.
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PMID:Bendazac decreases in vitro glycation of human lens crystallins. Decrease of in vitro protein glycation by bendazac. 862 Aug 22

The relationship between cataract extraction and diet was considered in a case-control study conducted in northern Italy. A total of 207 patients who had cataract extraction and 706 control subjects in a hospital for acute, nonneoplastic, nonoculistic, nondigestive tract diseases were interviewed during their hospital stay. Odds ratios (ORs) and their 95% confidence intervals (CIs), according to the intake of alcohol, coffee, tea, and cola, and frequency of intake of 34 food items and 8 micronutrients were derived from multiple logistic regression equations, including terms for age, sex, education, smoking status, body mass index, diabetes, and total calorie intake. Alcohol, coffee, decaffeinated coffee, tea, and cola intakes were not associated with cataract extraction. Among food items, reduced ORs for cataract extraction (highest tertile of intake compared to the lowest), with a significant inverse trend in risk, were found for intake of meat (OR 0.6, 95% CI 0.4 to 0.9), cheese (OR 0.7, 95% CI 0.5 to 1.0), cruciferae (OR 0.5, 95% CI 0.3 to 0.8), spinach (OR 0.6, 95% CI 0.4 to 0.9), tomatoes (OR 0.5, 95% CI 0.4 to 0.8), peppers (OR 0.7, 95% CI 0.4 to 1.1), citrus fruit (OR 0.5, 95% CI 0.2 to 1.3), and melon (OR 0.5, 95% CI 0.4 to 0.8). A significant increase in risk was found for the highest intake of butter (OR 2.8, 95% CI 1.2 to 6.4), total fat (OR 1.8, 95% CI 1.2 to 2.8), and salt (OR 2.4, 95% CI 1.4 to 4.0) compared to the lowest, and for consumption of oil other than olive oil (OR 1.6, 95% CI 1.1 to 2.2). Among micronutrients, lower ORs for cataract extraction (highest quintile of intake compared to the lowest) were found for intake of calcium (OR 0.5, 95% CI 0.3 to 0.8), folic acid (OR 0.4, 95% CI 0.2 to 0.7), and vitamin E (OR 0.5, 95% CI 0.3 to 1.0), while estimated intakes of methionine, retinol, beta-carotene, and vitamins A, C, and D were not associated. Thus, this study indicates that diet plays a considerable role in the risk of cataract extraction in this Italian population, with a protective action played by some vegetables, fruit, calcium, folic acid,and vitamin E, and an increased risk associated with elevated salt and fat intake.
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PMID:Food and nutrient intake and risk of cataract. 868 Jun 24

We assessed components of lenticular short-circuit current in adult hypertensive Dahl salt-sensitive rats (DS) during chronic control (0.4% sodium) versus high (3% sodium) dietary NaCl intake begun at the age of 4 weeks until rats were studied. We also evaluated the influence of barium, a potassium channel blocker, and ouabain, a specific inhibitor of Na+, K(+)-ATPase activity, by adding them to the anterior lens surface, thus measuring barium-sensitive, ouabain-sensitive, and barium- and ouabain-in-sensitive short-circuit currents. During control NaCl intake, short-circuit current in DS and their control group, Dahl salt-resistant rats (DR), did not differ significantly. DS were subclassified into cataract-prone rats and rats unlikely to develop cataracts on the basis of their initial pressor response to the change from a normal to high NaCl diet during the first weeks of age. Although only transparent lenses were studied, total lens short-circuit current was already markedly decreased in the cataract-prone subgroup compared with DS unlikely to develop cataracts and control DR. This was in sharp contrast to the increase in short-circuit current previously reported in Sprague-Dawley rats and now observed in control DR in response to high dietary NaCl. The decrease in lens short-circuit current in cataract-prone rats was associated with lower absolute values of barium- and ouabain-sensitive short-circuit currents as well as with low barium- and ouabain-insensitive short-circuit current. Although the barium- and ouabain-sensitive components of the short-circuit current were similar in DS unlikely to develop cataracts and DR, the barium- and ouabain-insensitive component of the short-circuit current was lower in DS unlikely to develop cataracts than values in DR. Interestingly, this component of lens short-circuit current also increased in DR during chronic high NaCl, whereas the opposite change occurred in cataract-prone DS and DS unlikely to develop cataracts. Thus, the barium- and ouabain-insensitive short-circuit current may be a mechanism that protects the normal lens from developing cataracts. Possible candidates for this short-circuit current component are voltage-dependent potassium channels, calcium-activated potassium channels, or both. Our studies show altered lens short-circuit current in response to high NaCl intake in cataract-prone DS and suggest the possibility of altered lens potassium transport during sustained hypertension but before loss of lens transparency.
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PMID:Altered lens short-circuit current in adult cataract-prone Dahl hypertensive rats. 879 30

Cause of mortality was studied in waterfowl in hypersaline playa lakes of southeast New Mexico during spring and fall migration. Mortality was not common in wild ducks resting on the playas during good weather. However, when birds remained on the lakes for prolonged periods of time, such as during experimental trials and stormy weather, a heavy layer of salt precipitated on their feathers. Sodium toxicity was the cause of death for all experimental mallards housed on playa water and for 50% of the wild waterfowl found moribund or dead during the spring of 1995. Gross lesions included heavy salt precipitation on the feathers, ocular lens opacities, deeply congested brains, and dilated, thin-walled, fluid-filled cloacae. Microscopic lesions in the more severely affected birds included liquefaction of ocular lens cortex with lens fiber swelling and multifocal to diffuse ulcerative conjunctivitis with severe granulocytic inflammation, edema, and granulocytic vasculitis resulting in thrombosis. Inflammation similar to that seen in the conjunctiva occasionally involved the mucosa of the mouth, pharynx, nasal turbinates, cloaca, and bursa. Transcorneal movement of water in response to the hypersaline conditions on the playa lakes or direct contact with salt crystals could induce anterior segment dehydration of the aqueous humor and increased osmotic pressure on the lens, leading to cataract formation.
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PMID:Sodium toxicity and pathology associated with exposure of waterfowl to hypersaline playa lakes of southeast New Mexico. 924 66

The solubility characteristics of collagen in human cataractous eye lenses were studied in relation to age. Post-operative cataractous lenses were collected form eye camps in Phulbani district of Orissa. These were preserved in 70% alcohol and immediately transferred to the laboratory. Various fractions in the collagen obtained from lens capsule of each lens sample were estimated. The salt-soluble and the acid-soluble collagens showed positive correlation with age. The insoluble and total capsular collagen increased with increasing age. The solubility percentage of collagen in salt and acid solutions decreased significantly with increasing age. The possible role of lens collagen in the development of cataract with increasing age is discussed in the background of cross-link theory of aging.
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PMID:Possible role of lens collagen in cataractogenesis. 956 18

Oxidative stress is believed to be involved in cataract development. The protective effect of the xanthomatine derivative, pirenoxine, and the 21-aminosteroid U74389F on oxidative insult in mammalian lenses was evaluated in vitro, ex vivo and in vivo. In vitro pirenoxine and U74389F inhibited lipid peroxidation induced by iron or haemoglobin in guinea-pig homogenate lens or whole lenses. Both compounds produced the same effect when lens oxidation was induced by superoxide producing system such as xanthine/xanthine oxidase or fMLP stimulated macrophages. In all the in vitro experiments, the values of biochemical lipid peroxidation markers, such as lipid hydroperoxides or thiobarbituric reactant substances, fell to the basal values with the addition of either pirenoxine (10(-5) M) or U74389F (10(-5) M). When two drops (60 microl) of the above molecular solutions (0.005 and 0.012% in saline respectively) were instilled in rabbit eyes (every hour for 8 hours over 2 days), the extracted lenses appeared to have better defences against an in vitro iron-induced lipid peroxidation, as shown by the values of conjugated dienes and lipid soluble fluorescent substances. These values also proved to be significantly lower when the same parameters were assayed in lenses from eyes where a lipid peroxidation was induced in vivo by haemoglobin or Diquat intravitreal injection followed by instillations of pirenoxine sodium salt or U74389F solutions (2 drops of about 60 microl every hour for 8 hours over 4 days) administered topically. Polarographic and chronocoulometric measurements were also performed in order to investigate the action mechanisms of both compounds. Experimental data indicate that the pirenoxine sodium salt and U74389F may be considered effective tools for rejecting an oxidative attack on the lenses, which can finally lead to cataract formation.
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PMID:Protective effect of pirenoxine and U74389F on induced lipid peroxidation in mammalian lenses. An in vitro, ex vivo and in vivo study. 1007 43


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