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)

Carbamylation of lens proteins induced conformational changes and may play a role in the development of cataracts in uremic patients. Thus, the activities of the urea cycle enzymes: carbamyl phosphate synthetase I, ornithine transcarbamylase, argininosuccinate synthetase, argininosuccinase and arginase, were determined in lens, retina and ciliary body-iris of calf and rabbit. No ornithine transcarbamylase activity was found in ciliary body-iris, lens and retina of calf and rabbit whereas carbamyl phosphate synthetase I, argininosuccinate synthetase, argininosuccinase and arginase activities in calf lens were 5.02 +/- 0.21, 9.50 +/- 0.29, 9.17 +/- 0.16 and 6.32 +/- 0.19 [mumol (g protein)-1 hr-1], respectively. Except arginase, the activities of carbamyl phosphate synthetase I, argininosuccinate synthetase and argininosuccinase in lens were 30-50% of the values in retina or ciliary body-iris. The Km for each of the substrates was obtained for argininosuccinate synthetase, argininosuccinase and arginase of calf lens. Activities of carbamyl phosphate synthetase I, argininosuccinate synthetase, argininosuccinase and arginase in clear human lenses, aged 67-87 years, were 0.11 +/- 0.01, 0.67 +/- 0.01, 0.20 +/- 0.01 and 0.58 +/- 0.03 (mumol lens-1 hr-1), respectively. Two-fold increase in the activity of arginase was found in senile cataracts, but all other enzymes had 36-87% decreases in activities. It is likely that the rise in arginase activity in cataracts could facilitate polyamine synthesis through ornithine and ornithine decarboxylase and additional formation of cyanate, a carbamylating compound, both of which have been implicated in cataract formation. Further, decreased activities of argininosuccinate synthetase and argininosuccinase together with increased arginase activity could lead to the depletion of arginine in senile cataracts.
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PMID:Urea cycle enzymes in retina, ciliary body-iris, lens and senile cataracts. 649 61

X-linked dominant inheritance with lethality in hemizygous males is a rare mode of inheritance. The three best-known disorders which seem to be inherited in this way, are incontinentia pigmenti (IP) Bloch-Sulzberger, oral-facial-digital I (OFD I) syndrome, and focal dermal hypoplasia (FDH syndrome, Goltz syndrome). It is the purpose of this article to give a review of the clinical and genetic aspects of the above-mentioned diseases and to add those disorders in which this mode of inheritance is discussed. These disorders are: X-linked chondrodysplasia punctata (CP), cervico-oculo-acusticus syndrome (Wildervanck syndrome, COA), congenital cataract with microcornea or slight microphthalmia, muscular dystrophy--hemizygous lethal, partial lipodystrophy with lipatrophic diabetes and hyperlipidemia, Aicardi syndrome, coxo-auricular syndrome, and Johanson-Blizzard syndrome. OTC deficiency is included in the study, although there is no lethality in utero, only in the neonatal period. A critical evaluation of the current literature is carried out.
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PMID:X-linked dominant inherited diseases with lethality in hemizygous males. 687 41

Research on the pathophysiology of the lens already in the early days of the last century led to first attempts to clinically influence cataract development with vitamins. More detailed investigation of lens aging and its interaction with internal and external cataract risk factors led to two different therapeutic strategies: (1) compounds or mixtures expected to slow down the aging processes in the lens (food additives) and (2) compounds to reduce or even arrest the effect of a specific harmful factor. Various mixtures expected to influence aging processes were even developed into approved OTC drugs although their effectiveness was never demonstrated. Among those compounds designed to act on a specific pathomechanism, mainly aldose reductase inhibitors were designed and successfully tested in animal studies. None of these,however, could be developed into a market-approved drug. Larger controlled clinical studies have been performed with various compositions of food additives, but also with nonsteroidal anti-inflammatory drugs such as salicylic acid and ibuprofen. None of the clinical trials,however, evidenced any convincing anti-cataract effect of the compounds or mixtures tested such that a successful anti-cataract drug still remains to be developed.
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PMID:[Cataract prevention. Therapeutic approaches and critical review of current status]. 1264 May 45