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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prevalence of intraoperative contamination of the eyelids, conjunctival sac, and aqueous humor of 50 canine eyes that underwent elective cataract surgery was determined, and the short-term outcomes for contaminated and noncontaminated eyes were compared by scoring media clarity, pupil size and shape, and behavioral evidence of vision during the initial 30-day postoperative period. Results of bacteriologic culture of anterior chamber samples were positive for 12 of the 50 (24%) eyes, but anterior chamber contamination was unrelated to results of bacteriologic culture of eyelids or conjunctival sac swab samples. Eyes undergoing phacoemulsification were less likely to be contaminated than were eyes undergoing intra- or extracapsular extraction. Eyes undergoing intra- or extracapsular extraction and eyes with anterior chamber contamination had a greater likelihood of developing glaucoma postoperatively. We did not detect an association between intraocular contamination and the surgeon performing the operation, the need for postoperative administration of tissue plasminogen activator, or the presence or absence of diabetes mellitus. Also, we did not detect any differences in outcome between eyes with and without intraocular contamination. Despite intraoperative bacterial contamination of the anterior chamber, bacterial endophthalmitis did not develop in any of the eyes.
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PMID:Intraocular bacterial contamination during cataract surgery in dogs. 778 43

In 148 healthy volunteers and 75 older patients the physiological aqueous humor secretion was calculated during the afternoon hours (13.00 to 20.00 hours) using the anterior chamber protocol of Fluorotron Master II (Coherent, Palo Alto, USA). Fluorescein eye drops were applied topically to each eye five times, 5 h before measurements. Healthy volunteers as well as patients had no history of ocular pathology, surgery or laser treatment. Further exclusion criteria were hypertension, diabetes, local and systemic drug therapy, neoplasia, kidney or liver diseases, contact lens, ocular trauma. Mean age of volunteers was 26.5 +/- 3.8 years; mean age of patients was 65.5 +/- 10.5 years. The aqueous humor flow in healthy volunteers (mean +/- standard deviation) was 2.26 +/- 1.0 microliters/min and in the older patients 1.91 +/- 1.1 microliters/min. Correlation coefficient between right and left eyes in the younger volunteers: r = 0.8; in the older patients: r = 0.54. The Mann-Whitney-U-test revealed a significant difference comparing mean aqueous humor flow in healthy volunteers with the mean aqueous humor flow in older patients (P < 0.01). The results in our study underline that the mean aqueous secretion does decrease with age of about 2.5% per decade. However, to date we do not know whether eyes with primary open-angle glaucoma or ocular hypertension show such a decrease in aqueous humor flow with age or whether there is an autoregulation mechanism in eyes with primary open-angle glaucoma that decreases aqueous humor secretion in relation to an increase of outflow facility.
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PMID:[Physiologic aging in aqueous humor minute volume of the human eye]. 781 85

The naturally occurring compound N alpha-acetylcarnosine (NAC) is proposed as the prodrug of L-carnosine (C) resistant to enzymatic hydrolysis by human serum carnosinase. Rabbit eyes were treated with 1% NAC, C or placebo and extracts of the aqueous humor from the anterior eye chamber were analyzed for imidazole content by reverse phase analytical high performance liquid chromatography (HPLC), thin-layer (TLC) and ion-exchange chromatographic techniques. The topical administration of pure C to the rabbit eye did not lead to accumulation of this compound in the aqueous humor over 30 min in concentration exceeding that in the placebo-treated matched eye. NAC showed dose-dependent hydrolysis in its passage from the cornea to the aqueous humor, releasing C after 15. 30 min of ocular administration of prodrug in a series of therapeutical modalities: instillation < or = subconjunctival injection < or = ultrasound induced phoresis. Different treatment techniques showed excellent toleration of 1% NAC by the eye. Once in the aqueous humor, C might act as an antioxidant and enter the lens tissue when present at effective concentrations (5-15 mmol/l). The advantage of the ophthalmic prodrug NAC and its bioactivated principle C as universal antioxidants relates to their ability to give efficient protection against oxidative stress both in the lipid phase of biological membranes and in an aqueous environment. NAC is proposed to treat ocular disorders which have the component of oxidative stress in their genesis (cataracts, glaucoma, retinal degeneration, corneal disorders, ocular inflammation, complications of diabetes mellitus, systemic diseases).
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PMID:N alpha-acetylcarnosine is a prodrug of L-carnosine in ophthalmic application as antioxidant. 889 6

Cathepsin A activity assayed with N-Cbz-Phe-Ala, N-Cbz-Glu-Tyr and N-Cbz-Glu-Phe as substrates, was measured in fresh corneas, lenses, aqueous humor, vitreous humor and choroid plus retinal pigment epithelium taken from normal bovine eye balls and in human intraocular fluids from the eye balls in various ocular diseases (cataract, glaucoma, diabetes, intraocular tumors). Cathepsin A exhibited a pH optimum at 5.0 and showed the highest specificity towards N-Cbz-Phe-Ala as a substrate. In bovine ocular tissues high cathepsin A activity was found in the choroid plus retinal pigment epithelium and in cornea. The lens and the vitreous humor showed low enzyme activity and the aqueous humor none at all. In the human aqueous humor of the eye with cataract cathepsin A activity was more than three times higher then in the eye with choroid tumor. In human vitreous humor in absolute glaucoma the activity was twice as high as in melanoma and almost three times higher than in the case of lung metastatic tumor. Diabetes in glaucoma increased seven fold cathepsin A activity in the vitreous humor.
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PMID:Cathepsin A activity of normal bovine ocular tissues and pathological human intraocular fluids. 910 5

Symptoms of primary open-angle glaucoma can be divided into main and accessory and risk factors. The main symptoms are increased intraocular pressure and changes in the visual field and optic disk characteristic of glaucoma. The accessory symptoms and risk factors are a family history of glaucoma, diabetes mellitus, myopia, poor discharge of aqueous humor, pseudoexfoliative syndrome, elements of goniodysgenesis and depositions of pigmented granules in the anterior chamber corner, and asymmetric intraocular pressure, humor discharge, and extent of optic disk excavation. Causes and diagnosis of nonglaucomatous hypertension and normal-pressure glaucoma are discussed.
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PMID:[Main principles of diagnosis of primary open-angle glaucoma]. 962 10

This review of recent articles on ocular toxicology concentrates on undesirable effects on the eye induced by systemically used xenobiotics. These include color vision deficiencies or visual field deterioration related to antiepileptic drugs, elevated intraocular pressure associated with inhaled corticosteroids, retinal detachments associated with systemic corticosteroids, rifabutin-induced uveitis, cocaine-related retinal hemorrhagic lesions in utero, deferoxamine-related decreases in vision, ocular allergy to bovine-derived collagen, and a large case study of hydroxychloroquine retinotoxicity. Other publications reviewed include a controlled study showing that glucose levels do not seem to alter color vision, a report that intravenous methotrexate can reach clinically meaningful levels in the aqueous humor, and a study showing the effect of systemic pentoxifylline on ocular blood flow and diabetes. With respect to systemic effects of topical ocular medications, there was a case report of apparent systemic exposure to pilocarpine from an Ocusert (Alza Corp., Palo Alto, CA), generalized urticaria after a single application of 1% cyclopentolate, and asthma induced with topical ketorolac. Readers are reminded that no drug achieves ultimate efficacy or ultimate safety. Thus, the decision to employ a given therapy involves a physician's evaluation of its therapeutic index, that is, the ratio between efficacy and toxicity.
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PMID:Ocular toxicology. 1017 10

Negative regulators of angiogenesis play a major role in maintaining vascular homeostasis. Thrombospondin-1 (TSP1) is a natural inhibitor of angiogenesis. This report examines the presence of TSP1 in ocular samples and determines whether its production is altered in diabetes. Western blot analysis detected a 140 kDa antiangiogenic fragment of TSP1(gp140) in vitreous samples prepared from normal human and rat eyes. Intact TSP1 was detected in aqueous humor samples prepared from normal rat and bovine eyes. In contrast, TSP1 was virtually absent in vitreous and aqueous humor samples prepared from diabetic rat eyes. Furthermore, production of TSP1 by microvascular endothelial cells in culture was sensitive to high concentrations of glucose. Retinal blood vessels appeared nonuniform and dilated in diabetic animals when compared to control animals. These results demonstrate that TSP1 and its antiangiogenic fragment are present in aqueous humor and vitreous of normal rat eyes and are dramatically reduced in diabetes. Thus, TSP1 may play a role in ocular vascular homeostasis and its absence may contribute to vascular dysfunctions associated with diabetes.
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PMID:Thrombospondin-1, a natural inhibitor of angiogenesis, is present in vitreous and aqueous humor and is modulated by hyperglycemia. 1062 7

This study was conducted to determine the elemental composition of the aqueous humor in cataract human eyes, with and without diabetes mellitus. The aqueous humor was obtained during cataract surgery from 11 patients with diabetes mellitus and 11 controls. Droplets of aqueous humor, after air-drying on carbon plates, were analyzed by X-ray microanalysis. Before surgery, the protein concentration in the anterior chamber was measured with a laser flare meter. Flare intensity was significantly higher in eyes with diabetes mellitus than in controls (p < 0.05). The X-ray microanalytical results showed that the relative sulfur content in the aqueous humor was significantly higher in the diabetic eyes than in the controls (p < 0.05). The content of elements representing the mobile ions in the aqueous humor, i.e., Na, Cl, K, and Ca was similar in both studied groups. We conclude from these data that the high sulfur content in aqueous humor of diabetic eyes may be related to a higher level of proteins found in the humor in these eyes.
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PMID:X-ray microanalytical and morphological observations of aqueous humor from cataract human eyes with and without diabetes mellitus. 1062 5

The high cytotoxicity of linoleic acid (LA) to cultured bovine lens epithelial cells is correlated with high uptake rates for the fatty acid (FA). Both, LA uptake and LA cytotoxicity strongly increase with the increasing LA-to-albumin molar ratio in the culture medium. Cellular uptake and cytotoxicity of LA can be competitively inhibited with the noncytotoxic palmitic acid. The findings may be of interest in view of the low albumin concentration in aqueous humor, resulting in extremely low buffering capacities for free FAs including LA, oleic acid and other cytotoxic cis-unsaturated free FAs, which are strongly raised in pathological situations like diabetes mellitus.
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PMID:Linoleic acid cytotoxicity to bovine lens epithelial cells: influence of albumin on linoleic acid uptake and cytotoxicity. 1075 40

The naturally occurring compound Nalpha-acetylcarnosine is proposed as a prodrug of L-carnosine that is resistant to enzymatic hydrolysis by carnosinase. Eyes of rabbits were treated with 1% Nalpha-acetylcarnosine, L-carnosine, or placebo and extracts of the aqueous humor from the anterior eye chamber were analyzed for imidazole content by reverse-phase analytical high performance liquid chromatography (HPLC) and thin-layer (TLC) and ion-exchange chromatographic techniques. Topical administration of pure L-carnosine to the rabbit eye did not lead to accumulation of this compound in the aqueous humor over 30 min in concentration exceeding that in the placebo-treated matched eye. Nalpha-Acetylcarnosine showed dose-dependent hydrolysis in its passage from the cornea to the aqueous humor, releasing L-carnosine after l5-30 min of ocular administration of the prodrug in a series of therapeutic modalities: instillation < or = subconjunctival injection < or = ultrasound-induced phoresis. Different treatment techniques showed excellent toleration of 1%Nalpha-acetylcarnosine by the eye. Once in the aqueous humor, L-carnosine might act as an antioxidant and enter the lens tissue when present at effective concentrations (5-l5 mM). The advantage of the ophthalmic prodrug Nalpha-acetylcarnosine and its bioactivated principle L-carnosine as universal antioxidants relates to their ability to give efficient protection against oxidative stress both in the lipid phase of biological membranes and in aqueous environments. Nalpha-Acetylcarnosine is proposed for treatment of ocular disorders that have a component of oxidative stress in their genesis (cataracts, glaucoma, retinal degeneration, corneal disorders, ocular inflammation, complications of diabetes mellitus, and systemic diseases).
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PMID:The natural histidine-containing dipeptide Nalpha-acetylcarnosine as an antioxidant for ophthalmic use. 1085 Oct 37


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