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)

To define the role of platelet-activating factor (PAF) in anaphylactic shock in the mouse, the suppressive effect of CV-3988, a PAF antagonist, on active and passive anaphylactic shock was studied. Various mouse strains treated or not treated with Bordetella pertussis (B. pertussis) were used. We found that the effect of CV-3988 on anaphylactic shock in the mice that were actively sensitized with bovine serum albumin plus B. pertussis differed markedly according to mouse strain. CV-3988 suppressed the anaphylactic shock in C3H/He and CBA/JN mice at a low dose of 3 mg/kg, whereas antagonists to other mediators such as histamine, serotonin, thromboxane A2 and leukotrienes did not show a suppressive effect. This suggests that PAF plays a major role in anaphylactic shock in these strains. On the other hand, CV-3988 did not suppress active anaphylactic shock in cataract Shionogi (CTS), NOD and DS strains even at a high dose of 30 mg/kg, which could be interpreted to suggest that PAF is not active in these strains. However, this possibility was ruled out based on the similar results obtained in passive anaphylactic shock and PAF-induced shock in these mice. Passive anaphylactic shock in CTS mice mediated by IgG1 antibody was markedly suppressed by CV-3988 but not at all by antagonists to other mediators. Furthermore, the suppressive action of CV-3988 against passive anaphylactic shock, and PAF-induced shock was greatly attenuated when the mice were pretreated with B. pertussis. From these results, the conclusion can be drawn that PAF is the main mediator of active and passive anaphylactic shock in the mouse in general, even though the effect of CV-3988 differs depending on the mouse strain and on whether or not B. pertussis treatment is used.
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PMID:Differential effect of a PAF antagonist CV-3988 on active and passive anaphylactic shock in various mouse strains. 181 38

Cataract is the major cause of blindness worldwide. Non-enzymic modification of lens proteins leading to a disruption of their short range order is an important route to cataract formation. A reaction between lens proteins and a compound found in the lens indicates a potential role for that compound in cataract formation. The reactions of glucose and fructose with lens protein in vitro were investigated. Fructose bound to lens protein at pH 6.9 in a time-dependent fashion over a period of 20 days. The reactions of both glucose and fructose with lens proteins and bovine serum albumin led to the formation of coloured and fluorescent compounds. The formation of such compounds was greater with fructose than with glucose. The kinetics of the reactions of lens proteins and bovine serum albumin with fructose as measured by the formation of the above compounds were not identical. This point must be appreciated when attempting to extrapolate from results obtained with bovine serum albumin as to the reactions of lens proteins. The incubation of lens proteins with fructose led to an enhancement of protein aggregation. The implications of the reactions between lens proteins and fructose for the formation of cataract in diabetics are discussed. Ibuprofen intake is associated with protection against cataract. At relatively high concentrations (10-20 mM) ibuprofen decreased the binding of fructose to lens protein: this decrease was statistically significant at selected times (Student's t-test, P less than 0.05). The formation of fluorescent compounds in the presence of fructose was also decreased by ibuprofen.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Non-enzymic modification of lens proteins by glucose and fructose: effects of ibuprofen. 201 2

Our previous study demonstrated that cataract Shionogi (CTS) mice, an inbred strain related to non-obese diabetic (NOD) mice, are T lymphocytopenic and that their T cell-mediated in vitro reactions, such as proliferative responses of spleen cells to T cell mitogens and alloantigens or production of IL 2 and IL 2 receptors after stimulation of spleen cells with Con A, are greatly reduced. To confirm these in vitro characteristics, in vivo immune responses of CTS mice to T-dependent and T-independent antigens were compared with those of some reference strains including NOD mice. Antibody responses of CTS mice after one injection of a high dose (10(8)) or one or two injections of a low dose (10(5)) of sheep red blood cells (SRBC) were markedly lower than those of the reference strains. The decrease was particularly striking in the IgM antibody production at primary response to both high and low doses, and the IgG antibody production at the secondary response to low dose. Similar lower antibody production was observed in CTS mice against bovine serum albumin (BSA). Little production of IgE antibody was observed from 1 through 3 weeks after an injection of BSA plus Bordetella pertussis. IgG1 response was observed at high incidence but lower in titer than those in the reference strains. Unexpectedly, in spite of the poor antibody production to BSA, potent systemic sensitization for anaphylactic shock was easily established; incidence of lethal shock being comparable with those in the reference strains. This suggests that CTS mice are highly susceptible to the effector phase of active anaphylactic shock. Cell-mediated immunity was also impaired. Delayed type of hypersensitivity to SRBC was low, and the rejection of the skin graft from NOD mouse did not occur. In contrast to the reduced T cell-mediated responses, no difference was found between CTS and reference strains with regard to the antibody production to LPS, a T-independent antigen. These in vivo findings are consistent with the previous in vitro study.
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PMID:Immune deficiency of cataract Shionogi (CTS) mouse. II. Impaired in vivo T cell-mediated immune response. 207 15

Proteasome, a high molecular weight protease complex (HMP, approximately 600 kDa) was isolated from bovine eye lens epithelium tissue. In contrast with prior reports, lens proteasome degraded the major lens protein alpha-crystallin and S-carboxymethylated bovine serum albumin at 37 degrees C, mostly to trichloroacetic acid precipitable polypeptides. The proteasome, thus isolated, was labile at 55 degrees C. As indicated by the ability of p-chloromercuribenzoate and N-ethylmaleimide to block activity, a thiol group is required for activity. Alpha-crystallin was oxidized by exposure to 60Co-irradiation under an atmosphere of N2O (1-50 kilorads). This dose delivered 0.1-5.7 mol of hydroxyl radicals per mol of crystallin. Irradiation resulted in increased heterogeneity, aggregation, and fragmentation of the crystallin preparation. The proteolytic susceptibility of alpha-crystallin to the lens HMP was enhanced by the irradiation in a dose-dependent manner up to 20 kilorads (.OH concentration up to 2.3 mol per mol of alpha-crystallin). When 50 kilorads (5.7 mol .OH per mol of alpha-crystallin) was used, there was extensive aggregation and no enhancement in proteolysis over the unirradiated sample. The data indicate that the lens HMP can degrade mildly photooxidized lens proteins, but proteins which are extensively damaged are not degraded and may accumulate. This may be related to cataract formation.
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PMID:Lens proteasome shows enhanced rates of degradation of hydroxyl radical modified alpha-crystallin. 234 Oct 52

Implantation of a hydrogel (IOGEL) intraocular lens in humans has been reported. The polyhydroxyethyl methacrylate (poly HEMA) matrix of this hydrogel is permeable to water soluble drugs and may adsorb agents used intracamerally during cataract extraction or topically during the postoperative period. This study compared the in vitro uptake and release of chloramphenicol, dexamethasone, epinephrine, pilocarpine, and bovine serum albumin by polymethylmethacrylate and hydrogel intraocular lenses with that of the intact crystalline lens of humans and rabbits. An in vivo study compared the uptake and release of chloramphenicol and dexamethasone by hydrogel lenses implanted in the anterior chamber of rabbit eyes with that of the rabbit's crystalline lens. The in vitro uptake and washout of epinephrine and pilocarpine by the hydrogel lens was comparable to the human lens. Uptake of chloramphenicol and dexamethasone by the hydrogel lens exceeded that of the human lens and, following a two-hour washout period, the dexamethasone content of the hydrogel lens remained significantly greater than the human lens. The uptake and washout of bovine serum albumin by the hydrogel lens was half that of the human lens. In vivo, the hydrogel lens efficiently eluted both chloramphenicol and dexamethasone. These studies show that a hydrogel lens will not act as a significant depot for drugs in the eye.
J Cataract Refract Surg 1989 Mar
PMID:Drug uptake and release by a hydrogel intraocular lens and the human crystalline lens. 272 18

We have developed a new quantitative method to determine protein concentration and number of cells in the aqueous in vivo. The principal instruments in the system were a He-Ne laser and a detection system for measuring scattered light intensity. The power of the He-Ne laser was 25 microW and the focused beam diameter was 20 microns. The laser beam was operated by an optical scanner. The sampling window, 0.3 X 0.5 mm, was fixed in the center of the laser path. For the protein concentration measurement, the laser beam was scanned for a length of 0.6 mm vertically, covering the sampling window. To minimize signal contamination by background laser scattering, scattered light intensity produced by aqueous protein (Sp) was calculated as follows. Sp = Si - (S'o + S''o)/2, where Si indicates scattered light intensity when the beam passed in the sampling window and S'o and S''o indicate scattered light intensity when the beam passed above and below the sampling window. For the cell counts, the laser beam (0.25 X 0.6 mm) was scanned over the sampling window and the detected peaks were counted. Each measurement mode took 0.5 seconds. The operation of the instrument and data analysis were performed by a personal computer. In in vitro measurements with human plasma solution in diluting factors ranging from 1/50 to 1/10(4), and bovine serum albumin solution in concentrations ranging from 1 g/100 ml to 1 mg/100 ml, significant linear correlations between the values for concentration and photon counts (/msec) were obtained in each solution (r, ranging from 0.987 to 0.998, P = 0.000). In in vitro experiments with latex particles with diameters of 2.02 or 2.95 microns, significant correlations between the number of detected peaks and latex particles were also obtained. However, as the number of latex particles decreased, the variation in the number of detected peaks was large. In 31 normal young adults, with an average age of 23 years, the average photon count was 4.1 +/- 1.0, which corresponded to 27 mg/100 ml according to the in vitro bovine albumin solution measurement, and there was no definite relation in photon counts between eyes with and without mydriatics. Twenty patients with incipient or immature cataract, whose ages averager 70 years, showed significantly higher average photon counts, 6.2 +/-2.5, than the above young adults.We concluded that this new method of determining protein concentration and cell number in the aqueous enabled us to make a noninvasive and quantitative evaluation of the inflammation in the anterior segment of the eye.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:New quantitative method to determine protein concentration and cell number in aqueous in vivo. 305 16

The concentrations of serum albumin (SA) in the conjunctival fluid were measured in 25 patients before surgery and in the post-operative period following cataract extraction. We found a significant increase in mean tear fluid SA concentration on the first post-operative day. The SA concentration remained high during the first 3 pre-operative levels. No correlation between the post-operative concentration profile of tear fluid SA and earlier findings of the tear lactoferrin (LF) profile of the same group of patients (Jensen et al. 1985) could be shown, although a trend towards an inverse relationship was apparent from the graphs. Pre-operatively, we found a significant positive correlation between age and concentration of SA in the conjunctival fluid (P less than 0.05) which might be interpreted as an increase in leakage from conjunctival vessels with age. This would, at least partly, explain the decreasing LF concentration with age (Jensen et al. 1986; McGill et al. 1984). It is concluded that transudate/exudate from the conjunctival vessels, represented by the change in the SA concentration in the conjunctival fluid, might be responsible for an initial post-operatively reduced concentration of LF and possibly other lacrimal gland proteins.
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PMID:Lactoferrin and serum albumin in the conjunctival fluid of eyes operated for senile cataract. 366 Nov 40

The reductone ascorbic acid, present in the crystalline lens in concentrations higher than those of glucose, is capable of undergoing nonenzymatic "browning" in the presence of lenticular proteins. We studied the nonenzymatic browning with ascorbate in model systems employing bovine serum albumin and lens crystallins. When bovine serum albumin, alpha-crystallin, or gamma-crystallin was incubated with [14C]ascorbic acid, the formation of yellow and then brown condensation products appeared to correlate with increasing protein-associated radioactivity. The fluorescence spectrum of these products was similar to that of homogenates of human cataractous lenses. We suggest that the nonenzymatic reaction of lens crystallins with ascorbic acid may contribute, at least in part, to the color changes of aging lenses and to the physical lenticular deterioration leading to senile cataract. High dietary intake of ascorbic acid did not affect the fluorescence spectrum of murine lenses; thus, we assume that the speed and extent of the lenticular browning reactions must depend on a deterioration of other factors of the multicomponent antioxidant system of the eye.
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PMID:The role of ascorbic acid in senile cataract. 386 54

The author assessed the physiological aging parameters of 38 apparently healthy subjects who were over 80 years old 1989, who were not on medication, and who had consulted with the Keio Health Counseling Center over 10 years. All subjects had no history of overt vascular disease and/or malignancy in 1989. In 17 of 38 subjects, physical, hematological and blood chemical parameters when they were in their 70s were analyzed. Many parameters were unchanged and remained within normal limits for ordinary adults. Cataract, atherosclerotic change of optic fundi and diagonal ear lobe creases were seen in all subjects during the study period. Concerning standard deviations, those of forced expiratory volume in one second/predicted vital capacity and pure tone average (acoustic ability) decreased with age, unlike those of other parameters. Furthermore, multiple regression analysis, revealed that serum albumin decreased but pure tone average, Scheie's atherosclerotic score, senile cataract, HDL-cholesterol blood urea nitrogen and forced expiratory volume in one second/predicted vital capacity increased with age. This study was not cohort study with selected subjects but shows very slight change of almost any parameter irrespective of age and abnormality can suggest the existence of disease.
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PMID:[The changes in physico-chemical parameters obtained from apparently healthy aged people followed over ten years]. 823 Jul 84

Auto-antibodies (Abs) against lens antigens (Ags) are present in most patients with age-related cataract, and with complement they kill lens epithelial cells (LECs) in vitro. We studied, in an animal model, whether cytotoxic Abs against lens Ags can be suppressed by oral administration of the Ags. Mice were fed calf lens homogenate, 4 mg/mouse, every 4 days for 4-5 weeks, or bovine serum albumin (BSA) before and after immunisation with beta-crystallins emulsified in complete Freund's adjuvant (CFA). Sera from these animals were analysed for Abs to beta-crystallins by enzyme-linked immunosorbent assay (ELISA) and protein blot analysis. In addition, we studied the proliferative response of T-lymphocytes to beta-crystallins. The titer of anti-beta-crystallin Abs in the control animals fed BSA gradually increased to 1.5 x 10(-6) by the 5th week after the first injection. In contrast, the titer of anti-beta-crystallin Abs in animals fed calf lens homogenate was reduced to 30-70% of the control. Feeding lens homogenate prior to or concomitant with beta-crystallins immunization, was more effective than feeding after immunization (65% suppression vs. 30% suppression, respectively). Also the proliferative response of T-lymphocytes to beta-crystallins in mice fed homogenate was suppressed significantly. Thus, oral administration of lens homogenate is a specific and nontoxic method of suppressing anti-beta-crystallin Ab production in mice. We are exploring the therapeutic value of oral administration of lens proteins in age-related cataract.
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PMID:Oral administration of lens homogenate suppresses antibody production in mice injected with beta-crystallin emulsified in CFA. 919 89


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