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PubMed2002

Serum status of carotenoids and tocopherols in patients with age-related cataracts: a case-control study.

BACKGROUND: Cataract is an important health problem that increase with age, causes decreased visual acuity and constitute a major cause of disability in the elderly. Epidemiological studies have shown that elevated serum levels and / or intake of several antioxidants, such as carotenoids, vitamin E and ascorbic acid, are associated with a diminished risk for cataracts. OBJECTIVE: To assess the serum fat-soluble antioxidant status in patients with cataracts and its relationship with visual function. METHODS: One hundred thirty eight patients with senile cataracts, classified according to visual acuity, and 110 age and sex-matched controls were studied for individual carotenoids and tocopherols in serum by a quality-controlled HPLC method. One-way ANOVA analysis and logistic regression analysis were applied. RESULTS: Higher serum levels of lutein and zeaxanthin were associated as risk factors for cataract while b-cryptoxanthin and g-tocopherol appeared as protective variables. Higher levels of zeaxanthin and lower concentrations of b-cryptoxanthin were associated with cataracts in people < 61y whereas only lower levels of g-tocopherol were shown in subjects >61y. No significant correlations (adjusted for sex and age) were found between visual acuity and serum concentrations of carotenoids or tocopherols. CONCLUSION: Although the relation between carotenoids and cataracts is biologically plausible, serum carotenoid levels are highly dependent on dietary intake and thus may not be clinically relevant biomakers for cataracts risk.

Age Factors↗
PubMed2001

A study of factors related to the incidence of cataract in patients with non-insulin dependent diabetes mellitus.

PURPOSE: To investigate the factors related to the development of cataract in patients with non-insulin dependent diabetes mellitus(NIDDM). METHODS: 792 NIDDM patients received ophthalmologic examinations including visual acuity, external status of the eyes, slit lamp microscopy and ophthalmoscopy. Glucose, urea nitrogen(BUN), creatinine(Cr), urine acid(UA), N-acetyl-beta 2-D-glucosaminidase (NAG), beta 2-microglobulin(beta 2-MG) and serum albumin in blood were quantitatively tested. Glucose, pH value, protein, cells, cast and ketobodies in urine were assayed. Diagnosis of cataract was based on lens opacities classification system II. Any patient meeting "NII", "CII" or "PII" level was diagnosed as cataract. RESULTS: The incidence of cataract in this group of NIDDM was 62.37% (494/792), which significantly related to the duration of the disease course, but not to the sex of the patient. The occurrence rate of cataract in patients suffering from NIDDM of less than five years duration, from five to ten years, and more than ten years was 49.67% (228/459), 71.84% (125/174), and 88.68% (141/159), respectively. The occurrence of cataract in patients diagnosed of the disease from five to ten years and more than ten years was much higher than that of those with the course of the disease less than five years(P < 0.05 and P < 0.001, respectively). Rising concentrations of blood urea nitrogen, creatinine, glycosylated hemoglobin HbA1c(G-HbA1c), N-acetyl-beta 2-D-glucosaminidase(NAG) and beta 2-microglobulin(beta 2-MG) indicated malfunction of the kidneys, and the rate of cataract occurrence in these patients was higher. CONCLUSION: This study indicates that prolongation of the duration of non-insulin dependent diabetes mellitus, renal dysfunction, as well as poor blood glucose control, may accelerate the development of cataract.

Acetylglucosaminidase↗
PubMed2003

[Prematurely aging OXYS rats as an animal model of senile cataract in human].

Cataracts remain the major cause of blindness and acuity of vision deterioration in the elderly. To date there are no effective methods of preventive measures of this disease and surgical removal of cataract-damaged lenses remains the only way to restore vision. To explore cataract pathogenesis and development methods of its prophylaxis are necessary fundamental investigation, which is impossible without biological models. As the first Russian her senile cataract model it is suggested to use the senescence-accelerated OXYS rat strain which was developed 30 years ago by selection and inbreeding of rats Wistar susceptible to cataractogenic effect of galactose (Institute of Cytology and Genetics, Novosibirsk). We conducted strong selection by the early cataract during 13 generations of OXYS rats. As the result at present time changes of OXYS rat lens appear by the 2 month, at 6 months these changes appear in 100% of animals (in rats Wistar--5%), at 12 month cataract affects both eyes. The data suggest that the cataract in rats OXYS develops simultaneously with progressive macular degeneration while changes of the eye lenses morphologically correspond to senile cataract in man.

Aging, Premature↗
PubMed2004

[Carnitine level in human lens and density of cataract].

PURPOSE: To evaluate whether the level of carnitine in human lens is affected by development of cataract. MATERIAL AND METHODS: The study covers 52 cases of cataract lenses extracted by ECCE. The nucleus of each lens was analyzed according to the level of total and free carnitine. The amount of cataract was determined by the microscopic and ophthalmoscopic examination. Cataracts were divided into 3 groups depending on the advanced degree of cataract. RESULTS AND CONCLUSIONS: It was possible to find statistically significant difference in mean carnitine level of total and free carnitine between lenses with mature cataract and lenses with partial cataract. This level was lower approximately by 30% in the lenses with dense opacification. This could be another proof for protective role of carnitine in development of human cataract and could trigger more researchon the subject of its supplementation in patients in older age.

Carnitine↗
PubMed2004

[Antibodies against lens proteins in the blood in patients with cataract].

Investigations were carried out to clarify the role of autoimmune phenomena in the pathogenesis of human cataract. We determined the antibodies to lens proteins of serum in the following groups of patients: patients with senile cataract, patients with diabetic cataract, patients with diabetes mellitus, dependent of insulin and without cataract, patients without cataract and without diabetes mellitus (healthy adults), using the plate gel with double diffusion method described by Ouchterlony. 98% patients with senile cataract, 100% patients with diabetic cataract and only 12% healthy adults showed positive reactions to the test. There is little evidence so far, to incriminate immunological mechanisms in the pathogenesis of cataract.

Adult↗
PubMed2005

[Influence of cataract and intraocular lens surgery on health-related quality of life].

PURPOSE: To evaluate the vision-related quality of life(QOL) in patients undergoing cataract surgery with the Japanese version of the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25). SUBJECTS AND METHODS: Subjects were 110 patients [70.4 +/- 9.2 (mean +/- standard deviation) years old] undergoing bilateral cataract surgery. Best-corrected visual acuity was 20/30 or worse in both eyes. The VFQ-25 was recorded before and 2 months after phacoemulsification and foldable intraocular lens implantation, and the influence of various clinical parameters was assessed. The VFQ-25 was also recorded in 69 glaucoma patients with visual field defects in both eyes, and in 31 normal subjects. RESULTS: The VFQ-25 scores before cataract surgery were as low as the scores obtained in glaucoma patients. Cataract surgery significantly improved VFQ-25 scores to the level of normal subjects Statistically significant improvements were observed in subscales such as general vision, near activities, distance activities, driving, peripheral vision, color vision, social functioning, dependency, role difficulties, mental health, and total score (p<0.001, paired t-test). The degree of improvement in VFQ-25 scores did not correlate with preoperative or postoperative visual acuity, uncorrected or corrected. The VFQ-25 scores improved more in younger patients, and improvement in the general vision subscale showed a significant negative correlation with age (r= -0.286, p=0.009, Pearson correlation coefficient). The degree of posterior subcapsular cataract in better eyes showed significant correlation with the improvement in subscales, such as distance activity (r =0.413, p<0.001), driving (r= 0.449, p=0.015), social functioning (r=0.308, p= 0.004), mental health (r=0.330, p=0.002), dependency (r=0.323, p=0.003), and total score (r=0.328, p=0.002). Other types of cataract had no correlation. Men tended to show more improvement in VFQ-25 scores by surgery than women, except for the dependency subscale. CONCLUSION: The current study quantitatively demonstrated that vision-related QOL is significantly impaired in patients with cataract, and that cataract surgery dramatically improves patients' QOL.

Adult↗
PubMed2006

[Tendencies of cataract surgery in Lithuania].

OBJECTIVE: To review the tendencies of cataract surgery in Lithuania. MATERIALS AND METHODS: More than ten years the data are collected from all medical institutions in Lithuania, where cataract surgery is performed. Each year from 1994 standardized questionnaires are sent to all centers of the cataract surgery and afterwards collected in the database. The questionnaires contain questions regarding the incidence of cataract surgery, operation methods, the rate of applied intraocular lenses, their models, etc. RESULTS: A total of 74,954 cataract operations were performed in Lithuania from 1994 till 2004. Phacoemulsification for the first was used in Lithuania in 1996. Since that time, 18,393 phacoemulsification operations have been performed. The first foldable intraocular lens was implanted in Lithuania in 1998. A total of 5,140 foldable intraocular lenses were implanted till 2005. It makes up 7.36% from total number of implanted intraocular lenses during the period under review. CONCLUSIONS: We have been observing a great quantitative and qualitative increase in the amount of cataract surgeries for last ten years. This is due to the newest cataract surgery methods (manual small incision cataract surgery, phacoemulsification), introduction of viscoelastic agents, new generation lenses (foldable: acrylic, silicone), and modern phacoemulsificators to clinical practice.

Age Factors↗
PubMed1991

[A population based epidemiological study of senile cataracts].

A population based study on senile cataracts was conducted on 295 participants in an ophthalmologic examination in a rural area of Ishikawa prefecture. Subjects were above 40 years of age and received an ophthalmologic examination and were personally interviewed. The following results were obtained. 1) Prevalence of senile cataracts increased with age. 2) For eyes with lens opacity grade III 66.3% showed a visual acuity below 0.7, while about 45% with lens opacity grade I or II was a visual acuity below 0.7. 3) Among those determined to have senile cataracts by this study the proportion with a prior diagnosis of senile cataracts was low, i.e., 36% even in advanced cataracts with lens opacity grade III. The proportion improved with worsened visual acuity and having a personal ophthalmologist. 4) Of those already diagnosed with senile cataracts, 56.7% failed to visit an eye specialist after than. This proportion tended to be lower in persons with worsened visual acuity. 5) About a half of those who continued to visit an eye doctor utilized anti-cataract medication. 6) The level of knowledge regarding senile cataracts was statistically lower with age.

Adult↗
PubMed1990

Regional enzymatic analysis of UV-B and streptozotocin induced diabetic cataract lens.

As the UV-B cataract and early stages of diabetic cataract in rats only touches the epithelium and anterior superficial cortex, a whole lens analysis is not meaningful, but a regional analysis with the freeze-sectioning device has to be performed. Scheimpflug photography with microdensitometric image analysis enables the scientist to discern in vivo single layers along the optical axis of the lens. UV-B cataracts (0.2 J/cm2, every 2nd day) and diabetic cataracts (Streptozotocin (STZ), 70 mg/kg BW) were induced in Brown-Norway rats. The stages of lens opacification were documented by Scheimpflug photography. 8 weeks after start of UV-B treatment and at several dates before onset of visible diabetic cataractous changes, the animals were sacrificed. The lenses were divided reproducibly into 4 or 7 parts such as an equatorial ring and several layers of the central cylinder from anterior to posterior part. The enzyme activity spectrum shows highly region related pattern that would not have been found in a whole lens analysis. Aldose reductase was activated before appearance of visible cataractous changes due to diabetes compared to normal lenses. In contrast Fructose-1,6-biphosphate-aldolase activity was lower before onset of visible changes than in normal lenses, but only within the 1st section where later visible cataractous changes of UV-B cataract could be detected.

Aldehyde Reductase↗
PubMedDate not supplied

[Autoimmune mechanisms of eye involvement in congenital cataracts in children].

A total of 112 children aged 6 months to 8 years with congenital cataracts (69 ones with bilateral and 43 with unilateral forms) and 34 mothers of these children were examined to estimate the activity of local and systemic autoimmune reactions to lenticular crystallines and retinal S antigen, differentiation between and diagnosis of congenital cataract pathogenetic forms. Lacrimal fluid antibodies were measured in 80 eyes with congenital cataracts and 29 ones with strabismus, blood serum antibodies in 72 children with cataracts, 20 without cataracts, 34 mothers of children with cataracts and 20 mothers of children without cataracts by the passive hemagglutination test (micromethod) with stable erythrocytic diagnostic agents. alpha, Bh, Bl, gamma crystallines and summary extracts of the cortical and nuclear layers were tested. The studies have demonstrated the significance of autoimmune reactions to lenticular crystallines in the pathogenesis of congenital cataracts and in involvement of the retina in the immunopathologic process.

Adult↗
PubMed1990

[Free fatty acid levels in the blood serum and aqueous humor of patients with cataract].

The authors present the results of determination of the level of free fatty acids in the serum and aqueous in patients with a senile cataract (23 persons), with cataract and glaucoma (9 persons), complicated post-uveitis cataract (10 persons) and diabetic cataract (10 persons). The level of the free fatty acids in senile cataract was significantly lower in the aqueous in comparison with the serum. Their content in senile cataract was significantly lower in comparison with cataract and glaucoma and with complicated cataract.

Aged↗
PubMedDate not supplied

[Lipid fluorophores of the crystalline lens in cataracts].

Microcolumn liquid and column chromatography technique is conjunction with UV-spectrophotometry and spectrofluorescent analysis were used to study lipid peroxidation products accumulated in human lenses during cataract formation by means of chromatographic separation in regard to the molecular weight and polarity properties. Cataract is characterized by the appearance of certain substances changing UV-absorption lipid spectra in the region of 230 and 274 nm and having special fluorescence (excitation--320-370 nm), (emission--405-460 nm). The same changes were observed by ultrasoundinduced lipid peroxidation of model lipid samples. The accumulated lipid peroxidation products are concentrated in the same chromatographic fractions that are responsible for the change of UV-absorption and fluorescent spectra of lipids of cataractous lenses. It is the evidence of free radical lipid peroxidation products accumulation in human lenses at cataract formation. Along with the formation of diene and triene conjugates in the lens lipids, cataract is characterized by the formation of cetodienes and of low molecular weight lipid fluorescent products of fatty acids oxidation with low polarity due to the appearance of tetraene derivatives of polyunsaturated fatty acids. The particular features of mature cataract are an increased intensity of long-wave lipid fluorescence in the blue-green region (430-460 nm) of the spectrum, formation of high molecular weight fluorescent lipid peroxidation products with high polarity, and smooth decrease in absorbance in the region of 220-330 nm. During cataract formation products of deep lipid peroxidation resulting from radical phospholipids and fatty acids polymerisation are accumulated. It is supposed that lipid peroxidation is an initial phase of membrane desintegration and formation of HMW-proteins in cataract.

Cataract↗
PubMedDate not supplied

[Accumulation of lipid peroxidation products in the human lens during cataract maturation].

130 human lens impaired with cataract of various etiology (senile, traumatic, complicated cataract) and of different cataract maturation (initial, immature, quite mature, mature, over-maturated) as well as 18 transparent lens were studied. Primary products of lipid peroxidation (LP, hydroperoxides), secondary products (ketodiens) and the end products (Shiff bases) were distinctly accumulated in cataract lens. Intermediates of primary LP products were accumulated in lens within early periods of cataract development but the end LP products were mainly found at the late steps of cataract formation. Accumulation of the LP products was not distinctly different in cataracts with various clinical manifestations but similar in the level of maturation, thus indicating that lipid peroxidation plays a universal role in the process of lens opacity. The data obtained suggest that inhibitors of free radical oxidation (antioxidants) may be employed in medicamental treatment of cataracts.

Aged↗
PubMed1978

Globular bodies: a primary cause of the opacity in senile and diabetic posterior cortical subcapsular cataracts?

We examined 9 cataracts from maturity onset diabetics and 4 senile posterior subcapsular cataracts by scanning electron microscopy, transmission electron microscopy, immunofluorescence for crystallin proteins and actin, histochemical methods and x-ray diffraction. The cataractous regions contained spherical globules up to 20 mu in diameter, often in a fibrous matrix. Some were extracellular Morgagnian globules, apparently formed by blebbing from the cell surface; others appeared to have been formed intracellularly. The area of globular degeneration was usually 300 mu deep, but had deeper fusiform extensions. Morphological changes in the cell cytoplasm varied according to their depth in the cataract. Electron microscopy showed intracellular and extracellular globules, many of them were bounded by lipid bilayer membranes. Immunofluorescent staining showed that all the globules contained gamma-crystallin; some contained alpha- and beta-crystallins and actin. All the globules contained higher concentrations of cysteine or cystine than the surrounding lens tissue but they did not react to stains for carbohydrate or calcium. X-ray diffraction studies showed that crystalline calcium salts were absent. Globules and cavities averaged 45% of the total area in cross section. Assuming an area of cataract to be 300 micron thick and that globules 1 mu in diameter scattered, while 2--20 mu in diameter reflected light, we calculated that light passing through such a thickness would be reduced by 65%. Thus the globules could account for most of the opacity of the cataractous area. Presumably the fibrous degeneration of the cells causes enough light scattering to account for the remainder of the reduction. Cataract patients complain of decreased visual acuity, a golden halo around objects, and difficulties when driving while facing oncoming traffic at night. These probably result from light scattering. In our previous experiments, globular bodies containing gamma-crystallin were found in cells grown in tissue culture, and blebs with increased acitn content similar to Morgagnian globules were formed in tissue culture by treating differentiated rat lens cells of stage 2 by cytochalasin D (which impaired microfilament function). These results suggest the possibility of simulating in tissue culture the morphological alterations seen in the cataractous cell.

Aged↗
PubMed1981

Recent advances in cataract operations--phacoemulsification, intraocular lens implantation and prolonged-wear soft contact lenses.

A standard cataract extraction involves removal of the entire cataractous lens through a 12- to 13-mm incision with the aid of a cryoprobe while phacoemulsification consists of removing the cataract through a 3-mm incision by breaking the lens into small pieces with an ultrasonically vibrating needle which is then used to aspirate the fragmented cataract. Most ophthalmic surgeons choose to carry out the standard cataract extraction because although phacoemulsification offers a more rapid rehabilitation due to smaller incisions, it requires special training and experience and expensive, complicated equipment. Once the cataract is removed, vision can be restored with strong cataract glasses, contact lenses or intraocular lens implants. Cataract glasses are the safest but produce a magnified image. Contact lenses produce more normal vision but are often difficult to handle. Intraocular lenses offer the most normal vision but are accompanied by an increased risk of complications.

Cataract Extraction↗
PubMedDate not supplied

Transglutaminase activity in normal human lenses and in senile cataracts.

Transglutaminase, the main function of which is to crosslink peptide chains through isopeptide bonds, has been detected in the lens of laboratory animals and in human cataracts and has been implicated in cataractogenesis. The transglutaminase activity has been estimated by measuring the amount of 3H-putrescine incorporation into dimethyl-casein of clear noncataractous human lenses and by comparing it with that of cataracts of different grades. Both the total and specific transglutaminase activity of highly cataractous lenses were less than those of normal lenses. During the progression of cataract (slightly moderately, and highly cataractous groups were compared), there was a substantial decrease in transglutaminase activity. In contrast to our findings, an increased transglutaminase activity has been reported in the lens of rats and mice with cataract mutation. This discrepancy is probably due to the different mechanisms involved in the development of human senile cataract and cataract in mutated laboratory animals.

Adult↗
PubMed1995

Oxidative stress-induced cataract: mechanism of action.

This review examines the hypothesis that oxidative stress is an initiating factor for the development of maturity onset cataract and describes the events leading to lens opacification. Data are reviewed that indicate that extensive oxidation of lens protein and lipid is associated with human cataract found in older individuals whereas little oxidation (and only in membrane components) is found in control subjects of similar age. A significant proportion of lenses and aqueous humor taken from cataract patients have elevated H2O2 levels. Because H2O2, at concentrations found in cataract, can cause lens opacification and produces a pattern of oxidation similar to that found in cataract, it is concluded that H2O2 is the major oxidant involved in cataract formation. This viewpoint is further supported by experiments showing that cataract formation in organ culture caused by photochemically generated superoxide radical, H2O2, and hydroxyl radical is completely prevented by the addition of a GSH peroxidase mimic. The damage caused by oxidative stress does not appear to be reversible and there is an inverse relationship between the stress period and the time required for loss of transparency and degeneration of biochemical parameters such as ATP, GPD, nonprotein thiol, and hydration. After exposure to oxidative stress, the redox set point of the single layer of the lens epithelial cells (but not the remainder of the lens) quickly changes, going from a strongly reducing to an oxidizing environment. Almost concurrent with this change is extensive damage to DNA and membrane pump systems, followed by loss of epithelial cell viability and death by necrotic and apoptotic mechanisms. The data suggest that the epithelial cell layer is the initial site of attack by oxidative stress and that involvement of the lens fibers follows, leading to cortical cataract.

Cataract↗
PubMed1995

Barriers to acceptance of cataract surgery among patients presenting to district hospitals in rural Malawi.

The objective of this research was to assess the barriers to cataract surgical acceptance by blind rural Malawians recognized and referred for surgical correction at district hospitals. Cataract blind recognized and referred for surgery by the ophthalmic assistants in Chikwawa and Nsanje Districts were interviewed 9-12 months after enrolment to determine if they had undergone cataract surgery and to assess factors associated with surgical acceptance. There were significant gender-specific baseline differences between men and women presenting to the ophthalmic assistants. Patients living near the district hospital were also most likely to present to the ophthalmic assistant. Men with lower socioeconomic status were more likely to accept surgery than men with higher socioeconomic status. Men and women who either talked to someone about cataract surgery or knew another aphakic patients were more likely to accept surgery. The best approaches to improving cataract acceptance given existing resources might be to encourage patients undergoing cataract surgery to educate and motivate others to accept surgery and to train existing village level health staff in cataract recognition and referral. Economic barriers and lack of family support are likely to continue to impede improved cataract surgical acceptance, especially among women.

Cataract Extraction↗