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

We report the presence of lens opacities in patients with prolactin-secreting microadenomas of the pituitary gland. The occurrence of lens opacities was related to prolactin serum levels and appeared only in women. The mechanism by which prolactin induces cataract is not known, although this hormone could affect the lens's permeability to ions, water, sugars, and amino acids. Moreover, the lens opacities found in women but not in men seem to indicate synergism with estrogens.
 ...
PMID:Hyperprolactinemia and lens opacities. 147 97

Studies were carried out comparing the ability of urea extraction and sonication to solubilize the water-insoluble (WI) protein fraction from human lens tissue. Sonication and urea extraction were able to solubilize greater than 80% of the insoluble protein whether whole lenses or lens nuclei were used. This was true for normal lens and +1 cataracts; however, only 60% solubilization was obtained with the WI fraction from more advanced cataracts. Equal aliquots of a WI fraction from both pooled normal and pooled cataract lens nuclei were solubilized with and without reducing agents. The addition of dithiothreitol (DTT) had no significant effect on solubilization of the normal lens WI fraction. DTT did increase the protein solubilized from the cataract WI fraction by 30% with urea extraction; however, no increase was seen with sonication. When sodium borohydride was used as the reducing agent, essentially the same results were obtained. The solubilized protein populations were identical by SDS-PAGE and amino acid analysis. The addition of reducing agents had no effect on the amino acid content of the solubilized proteins with the single exception of lysine. This amino acid was markedly decreased in the proteins extracted in the presence of 40 mM sodium borohydride, but not with DTT. These data suggest that the borohydride not only increased the amount of protein solubilized, but likely also stabilized glycated lysine residues during the acid hydrolysis. Therefore, sonication readily provides a soluble preparation of the WI proteins from normal and cataract lens nuclei without the need for denaturing agents, however, disulfide-linked and lysine modified crystallins were best solubilized with urea.
 ...
PMID:Studies on the solubilization of the water-insoluble fraction from human lens and cataract. 148 36

We examined the latex surgical gloves used by 56 primary surgeons in 454 ophthalmic surgical procedures performed over a 7-month period. Of five techniques used to detect pinholes, air inflation with water submersion and compression was found to be the most sensitive, yielding a 6.80% prevalence in control glove pairs and a 21.8% prevalence in postoperative study glove pairs, for a 15.0% incidence of surgically induced perforations (P = 0.000459). The lowest postoperative perforation rate was 11.4% for cataract and intraocular lens surgery, and the highest was 41.7% for oculoplastic procedures. Factors that correlated significantly with the presence of glove perforations as determined by multiple logistic regression analysis were oculoplastic and pediatric ophthalmology and strabismus surgical procedures, surgeon's status as a fellow in training, operating time, and glove size. The thumb and index finger of the nondominant hand contained the largest numbers of pinholes. These data suggest strategies for reducing the risk of cross-infection during ophthalmic surgery.
 ...
PMID:Occult glove perforation during ophthalmic surgery. 149 36

Eighteen eyes with coexisting cataract and vitreoretinal disease underwent combined phacoemulsification, pars plana vitrectomy, and posterior chamber lens implantation. Preoperative vitreoretinal disease included nonclearing vitreous hemorrhage (eight eyes), vitreous hemorrhage and tractional retinal detachment (three eyes), tractional retinal detachment (one eye), epiretinal membranes (three eyes), peripheral uveitis (two eyes), and a retained intraocular metallic foreign body (one eye). Postoperative visual acuity improved in each case; 14 eyes achieved visual acuity between 20/20 and 20/80 during an average postoperative period of 11 months (range, 3 to 39 months). Perioperative complications included an iatrogenic retinal break (one eye) and pupillary block glaucoma (one eye). Four eyes required YAG laser capsulotomy postoperatively. Phacoemulsification did not interfere with corneal clarity, allowed water-tight wound closure during vitrectomy, and preserved the capsular bag, allowing endocapsular fixation of the posterior chamber lens. Combining phacoemulsification, posterior chamber lens implantation, and pars plana vitrectomy allows rapid visual rehabilitation and functional unaided vision in these eyes.
 ...
PMID:Combined phacoemulsification, pars plana vitrectomy, and posterior chamber intraocular lens insertion. 149 24

Movement of water in the lens, specifically water diffusion, was examined with diffusion imaging and H217O-enhanced proton imaging. Diffusion imaging showed restricted water self-diffusion in the cortex which was not concurrent with the change in proton density; nevertheless it was dependent on the gradient direction and might be related to lens fiber/protein organization. The difference in water diffusion patterns between control and galactosemic cataract was subtle but distinguishable. On the other hand, intracameral H217O injection allowed visualization of water movement across the lens. In galactosemic cataracts, water diffused from the anterior cortex towards posterior cortex and into the vitreous. This pattern was not seen in the normal lens.
 ...
PMID:High-resolution MR imaging of water diffusion in the rabbit lens. 154 30

The non-invasive method of 1H-nuclear magnetic resonance (1H-NMR) spectroscopy was applied to rat whole lens. The alterations of aging and experimentally induced cataract on protein structures in rat lenses were examined by comparing high resolution 1H-NMR spectra. 1H-NMR measurements were carried out using the water suppression method and resolution enhancement method. The 1H-NMR spectra of normal lens showed narrow resonance lines of lactate and broad ones of aliphatic amino acid residues of lens protein. There was no remarkable change in the spectral pattern of normal lenses within one week. There was also no effect of aging on the spectral pattern of normal lenses. On the other hand the lines due to the aliphatic amino acid residues of the galactose cataractous lens protein were narrower than those of normal lens. This finding suggests that the increase of mobilities of the residues caused by galactose cataract is reflected by the spectral pattern.
 ...
PMID:[1H-NMR study on protein of normal and galactose cataractous rat whole lenses]. 155 69

For quantitative evaluation of cataract-related changes in lens proteins and lens water, the relative contents of water and SH residues and changes in the microenvironments of aromatic amino acid residues were quantitatively examined in cataract of the rat lens which had been induced by sodium selenite. Using Raman spectroscopy, results were compared with those of age-matched control lenses. The relative contents of water and SH residues decreased with increasing age in normal lenses from 3 to 8 weeks of age. In the cataractous lens, the relative water content increased constantly as compared with that of age-matched controls. The relative SH residue content continued to decline in the cataractous lenses of animals at every age. The microenvironments of tyrosine residues in cataractous lenses also changed progressively.
 ...
PMID:Estimation of structural changes in the cataractous rat lens using Raman spectroscopy. 157 84

A model eye water cell was used to evaluate the optical performance of biconvex, meniscus, and plano-convex (spheric and aspheric) monofocal poly(methyl methacrylate) intraocular lenses when the lenses were centered and when they were decentered 1 mm and 2 mm. Resolution, induced astigmatism, and modulation transfer function measurements were performed for all lenses with the more convex surface of the lens oriented toward the incident light. The same measurements were performed for the plano-convex and meniscus lenses in the reverse orientation. The lens shapes least affected by decentration were the biconvex and spheric plano-convex with the convex surface oriented toward the incident light. When centered, the aspheric plano-convex lenses had the best overall contrast performance based on the modulation transfer function measurements. However, once decentered the performance of the aspheric lenses approached that of the meniscus lenses in the reverse orientation, the lens shape which had the worst performance.
J Cataract Refract Surg 1992 May
PMID:Optical performance of decentered monofocal intraocular lenses. 159 35

L-buthionine-S,R-sulfoximine (BSO), a specific inhibitor of GSH biosynthesis, was administered four times daily to mouse pups on post-natal days 7 and 8, inducing initiation of opacification on day 9. The initial progression of the cataract (less than 24 hr) was divided into four stages: (1) developing floriform; (2) mature floriform; (3) degenerate floriform; and (4) amorphous translucent cataract. Following this, dense corticonuclear opacities developed within several days. Two-dimensional gel electrophoresis of water-soluble whole lens extracts indicated that the most rapid early cataractous changes, occurring mainly during stage 2, were loss of the two major components of the heavy beta-crystallin fraction, a 31-kDa basic polypeptide and an acidic component at 27 kDa, concomitant with the appearance of new species at 30 and 25 kDa. This was followed by more extensive modification of both alpha and beta-crystallins during stages 3 and 4 and the appearance of abnormal species at 26, 19 and 18 kDa, which were slightly more acidic than the major normal alpha A-crystallin polypeptide. The gamma-crystallin components, relatively unaffected at stage 4, were then lost rapidly as dense opacities ensued. By contrast with the water-soluble fraction, the normal day 9 urea-soluble fraction was deficient in gamma-crystallin polypeptides and enriched in anodic components whose relative electrophoretic mobilities were similar to those reported previously for phosphorylated bovine alpha A-crystallin and several cytoskeletal polypeptides. At stage 4 of the cataract, the modifications of normal alpha and beta-crystallin components in the urea-soluble fraction paralleled those in the water-soluble fraction, but the products seen were more numerous. In addition, the cytoskeletal proteins were no longer detectable. Substantial increases in lens Ca2+ that precede all of the above changes in lens polypeptide composition suggest that Ca(2+)-activated proteolysis may play a major role in development of BSO cataracts.
 ...
PMID:Progressive modifications of mouse lens crystallins in cataracts induced by buthionine sulfoximine. 162 46

Addition of calpain II (EC 3.4.22.17) to soluble proteins from 10-day-old rat lens caused an increase in turbidity and production of water-insoluble protein. The insolubilization increased with higher concentrations of both lens protein and calpain II, it could be prevented by the cysteine protease inhibitor E-64; it required at least 0.5 mM Ca2+, it was limited to 6% of the soluble protein present and resulted from precipitation of proteolyzed beta-crystallin polypeptides. When compared by two-dimensional electrophoresis, the insoluble beta-crystallin polypeptides produced by calpain II were similar to insoluble beta-crystallin polypeptides found in cataractous lenses. Trypsin also caused insolubilization of beta-crystallin polypeptides, but these polypeptides were unlike polypeptides produced during cataract formation. These data suggested that the loss of solubility was due to a specific removal of N/or C-terminal extensions from beta-crystallin polypeptides by calpain II, and that a similar process may occur in vivo during cataract formation. It is hypothesized that the insoluble protein produced by calpain II causes cataract by increasing light scatter in the lens.
 ...
PMID:Calpain II induced insolubilization of lens beta-crystallin polypeptides may induce cataract. 162 59


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>