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At least 649 records · Page 36Linked to original sources
PubMed1998

Enzyme-linked immunosorbent assay for detection of feline herpesvirus 1 IgG in serum, aqueous humor, and cerebrospinal fluid.

Feline herpesvirus 1 (FHV) is an important cause of feline ocular and respiratory disease, but the role the virus plays in central nervous system disease of cats has not been explored. The study described here was performed to validate an indirect enzyme-linked immunosorbent assay (ELISA) to detect FHV-specific IgG antibodies for use in feline epidemiologic, ocular, and central nervous system disease studies. The indirect IgG ELISA was applied to serum, aqueous humor, and cerebrospinal fluid from cats. Serum FHV IgG ELISA results were compared with those of serum neutralization in client-owned cats and laboratory-housed cats following vaccination. Of the 100 client-owned cats tested by ELISA, 97 had detectable FHV IgG; 95 had titers >32. The FHV IgG ELISA was more sensitive than serum neutralization and could be used with aqueous humor and cerebrospinal fluid. Cats with inflammatory central nervous system or ocular diseases had significant leakage of serum proteins into aqueous humor and cerebrospinal fluid, necessitating use of cutoff values derived from serum when these fluids were assessed.

Animals↗
PubMed1985

Gammaglobulins and immunocomplexes in aqueous humor and serum of patients with senile cataract.

The authors have measured the gammaglobulins and the immunocomplex levels (CIC) in aqueous humor and serum of 14 patients (3 males and 11 females) over 50 years old, who were affected by different types of cataract. Even if the authors have examined a limited number of samples, the results confirm the previous data which also showed very low levels of IgG, IgA, IgM, IgE, CIC in aqueous humor.

Aged↗
PubMed1997

Aqueous humor penetration of topically applied ciprofloxacin, ofloxacin and tobramycin.

UNLABELLED: The purpose of this study was to determine the aqueous humor concentrations of topically applied ciprofloxacin (CAS 86393-32-0), ofloxacin (CAS 82419-36-1) and tobramycin (CAS 79645-27-5). Thirty patients undergoing cataract extraction or trabeculectomy were randomly divided into three groups and each of the group received either 0.3% ciprofloxacin, ofloxacin or tobramycin topical drops preoperatively. Eyedrops were instilled for six times at a frequency of one drop every 15 minutes, beginning 90 minutes before initiation of the surgery. At the time of surgery, 0.1 ml aqueous fluid was aspirated from the anterior chamber. Concentrations of the antimicrobial agents were determined using the microbroth dilution procedure outlined by the National Committee for Clinical Laboratory Standards. Escherichia coli (ATCC 25922) was used as a standard strain for determination of minimal inhibitory concentrations (MICs). The mean aqueous levels of ciprofloxacin and ofloxacin were found to be 0.092 +/- 0.077 microgram/ml, 0.964 +/- 0.693 microgram/ml, respectively. Tobramycin did not reach the concentration that could be detected by applied method. CONCLUSION: The mean aqueous humor levels of ofloxacin and ciprofloxacin were more than the MICs levels for most of the ocular pathogens which may cause postoperative endophthalmitis.

Administration, Topical↗
PubMed1979

[Experimental investigations of the aqueous humor and blood serum of rabbits following injection of tobramycin].

In animal experiments the concentration of the antibiotic Tobramycin in the aqueous humor and blood serum following intramuscular and subconjunctival injections was tested by diffusion on agar plates. After intramuscular injections, only traces of Tobramycin were found in the aqueous humor, but a significantly higher concentration of the antibiotic was obtained by subconjunctival injections. The subconjunctival application of the antibiotic was well tolerated.

Animals↗
PubMed1995

[Comparison between local and systemic administration of cyclosporin A on the effective level in conjunctiva, aqueous humor and serum].

Cyclosporine is an important tool for the therapy of immunological diseases of the cornea and conjunctiva, as well as the treatment of patients with high-risk corneal grafts. However, potentially severe systemic side effects are disadvantageous. The purpose of our study was to determine if topical ocular application leads to about the same concentrations in ocular tissues as systemic application. Therefore, the concentration of cyclosporine in conjunctiva, aqueous humor and blood was measured by radioimmunoassay in six patients with systemic administration of cyclosporine and ten patients who received one drop of topical cyclosporine 2% four times prior to cataract surgery. All patients with systemic application showed measurable concentrations of cyclosporine in blood, as did four patients in the group receiving topical cyclosporine. There was no significant difference between both groups concerning cyclosporine concentration in aqueous humor. The level of cyclosporine in the conjunctiva was significantly higher after topical application (P < 0.02). In conclusion, therapy with cyclosporine eye drops results in levels in the conjunctiva and aqueous humor that are comparable to or even higher than those after systemic application if the last application was no more than 18h prior to the measurement. Therefore, topical ocular application of cyclosporine, which reduces or eliminates the drug's systemic side effects, can be used to induce local immunosuppressive activity, particularly in the treatment of superficial immunological diseases and after limbal allograft transplantation.

Administration, Oral↗
PubMed1983

[Changes in ocular tonus, pH and concentration of ascorbic acid and lactic acid in the aqueous humor of rabbits treated with clonidine].

The authors state the results of their research on the modification of the aqueous humor caused by the instillation of the Clonidine in a group of ten rabbits. The results of these studies illustrate the variations of pH, the ocular tone, the concentration of lactic and ascorbic acid. In all the rabbits examined was instillated Clonidine for one hour in RE while in LE distilled water was instilled for the control. For two hours from the beginning of the experiment every 10 minutes measurements of the ocular tone in both eyes were taken. At the end of two hours a sample of aqueous humor was taken from LE and RE. It was found that: 1) The drugs produced a vary quick and prolonged decrease of the ocular tone. 2) There are no significant variations in the pH or in the concentration of lactic acid. 3) There was a notable reduction of the concentration of ascorbic acid.

Animals↗
PubMed1983

[Changes in ocular tonus, pH and concentration of ascorbic acid and lactic acid in the aqueous humor of rabbits treated with epinephrine].

The authors state the results of their research on the modification of the aqueous humor caused by the instillation of the Epinephrine in a group of ten rabbits. The results of these studies illustrate the variations of pH, the ocular tone, the concentration of lactic and ascorbic acid. In all the rabbits examined Epinephrine was instillated in the RE while in the LE distilled water was instillated for the control. For two hours from the beginning of the experiment, every 10 minutes measurements of the ocular tone in both eyes were taken. At the end of the two hours a sample of aqueous humor was taken from the RE and LE; It was found that: 1) The drugs produced a vary quick and prolonged decrease of the ocular tone. 2) There are no significant variations in the pH or in the concentration of lactic acid. 3) There was a notable reduction of the concentration of ascorbic acid.

Animals↗
PubMed1993

[Plasminogen activator and PAI. Detection in aqueous humor of the human eye].

Tissue-type plasminogen activator (t-PA), a serine protease that catalyzes the conversion from plasminogen to plasmin, plays an important role in the fibrinolytic system and has also in recent years attracted attention in the field of ophthalmology. In order to examine the role of t-PA in the physiology of the anterior segment, we detected t-PA in aqueous humor by using immunoassays. The samples were taken by keratocentesis prior to cataract or glaucoma surgery. The sample volumes ranged from 50-200 microliters. The quantities of t-PA Ag and plasminogen-activator inhibitor (PAI) Ag were determined by using enzyme-linked immunosorbent assays. We determined t-PA and PAI in the aqueous humor of 54 patients between 32 and 87 years of age. The t-PA Ag levels ranged from 0.2 to 1.9 ng/ml (average 0.8 ng/ml), PAI-Ag from 0.2 to 1.7 ng/ml (average 0.9 ng/ml). The values measured in men were slightly higher than those measured in women. No association between t-PA and PAI levels and accompanying diseases or metabolic disorders was noted. Precise knowledge about the presence of t-PA in aqueous humor is a prerequisite for the recognition of pathological events following intraocular fibrin formation and may be an important basis for the therapeutic use of rt-PA in the intraocular inflammatory process.

Adult↗
PubMed1983

[Changes in ocular tone, pH, ascorbic acid and lactic acid concentration in the aqueous humor of rabbits treated with aceclidine].

The Authors state the results of their research on the modification of the aqueous humor caused by the instillation of the Clonidina to the concentrations of 0,I25% in a group of ten rabbits. The results of these studies illustrate the variations of pH, the ocular tone, the concentration of lactic and ascorbic acid. In all the rabbits examined Clonidina was instillated in the RE while in the LE distilled water was instillated for the control. For two hours from the beginning of the experiment, every IO minutes measurements of the ocular tone in both eyes were taken. At the end of the two hours a sample of aqueous humor was taken from the RE and LE; It was found that: I) The drugs produced a very quick and prolonged decrease of the ocular tone. 2) There are no significant variations in the pH or in the concentration of lactic acid. 3) There was a notable reduction of the concentration of ascorbic acid.

Animals↗
PubMed2002

The effect of excimer laser keratectomy on corneal glutathione peroxidase activities and aqueous humor selenium levels in rabbits.

BACKGROUND: The formation of free oxygen radicals has been demonstrated in the corneal tissue after 193 nm laser irradiation. Cornea has several defense mechanisms that protect against oxidative damage. One of them, glutathione peroxidase (GPx), catalyzes the destruction of hydrogen peroxide and lipid hydroperoxide. Selenium is a trace element which is incorporated into the selenoenzyme GPx. In the present study, the effect of excimer laser keratectomy on corneal GPx activities and aqueous humor selenium concentrations in rabbits was evaluated. METHODS: Animals were divided into five groups, and all groups were compared: controls (group 1), after epithelial scraping (group 2), transepithelial photorefractive keratectomy(PRK; group 3), superficial traditional PRK (50 microm; group 4) and deep traditional PRK (100 microm; group 5). Corneal GPx activities were measured by a modification of the coupled assay procedure. Aqueous humor selenium concentrations were determined using hydride generation atomic absorption spectrometry. RESULTS: Corneal GPx activities were significantly lower only in group 5 ( P<0.05), and the selenium concentration in the aqueous humor did not change in any group. CONCLUSION: Deep corneal photoablation inhibits GPx enzyme activities in the cornea. Therefore, antioxidants may be useful in reducing free radical-mediated complications after excimer laser corneal photoablation.

Animals↗
PubMed1993

[Effect of the calcium channel blocker nicardipine on intraocular pressure and aqueous humor dynamics in rabbit].

The effects of nicardipine hydrochloride (NH), a calcium channel blocker, on the intraocular pressure (IOP) and aqueous humor dynamics were studied in the rabbit eye. Thirty micrograms/kg of NH administered intravenously by bolus injection into an ear vein significantly lowered IOP for 5 to 30 minutes. But topical administration of NH significantly increased IOP, as compared with the fellow control eye at 15 and 30 minutes. This increased IOP was a dose-dependent response; the maximum effect was 4.3 +/- 0.6 mmHg at 15 minutes after administration of 0.1%NH. Severe hyperemia was observed at the limbus for 3 hours after topical administration. The aqueous flow rate after topical application of 0.1%NH showed no significant difference between treated and fellow control eye. However, the coefficient of aqueous outflow after topical application of 0.1%NH was significantly decreased (0.08 +/- 0.01 microliters/min/mmHg: p < 0.05) as compared with fellow control eye (0.13 +/- 0.02 microliters/min/mmHg). The penetration level of 0.1%NH into the aqueous humor of the rabbit eye was 0.22 +/- 0.13 micrograms/ml, 30 minutes after topical administration. Systemic NH decreased IOP, but topical NH increased IOP by increasing resistance of aqueous outflow.

Animals↗
PubMed1985

Cutaneous acetone depresses aqueous humor ascorbate in guinea pigs.

The purpose of the present investigation was to determine the concentration of ascorbate in the aqueous humor of guinea pigs over a 1-year period following the cutaneous application of a potential cataractogenic agent, acetone. Forty young guinea pigs received 15 ml acetone in small doses on their backs over a 6-week period; the ascorbate in their aqueous humor did not increase above 10 mg/100 ml during a 1-year test period. Ten control animals received only saline on their backs and the ascorbate concentrations steadily increased from 12 to over 18 mg/100 ml during the same time period. Three months after acetone treatment 12 animals (30%) developed cataracts and their ascorbate levels dropped to below 9 mg/100 ml after 1 year.

Acetone↗
PubMed1996

Distribution of azithromycin into brain tissue, cerebrospinal fluid, and aqueous humor of the eye.

To measure the concentrations of azithromycin in the central nervous system, 20 patients with brain tumors (group I) received a single 500-mg oral dose of azithromycin either 24, 48, 72, or 96 h prior to the tumor removal operation and 10 patients with cataracts undergoing surgery (group II) and 7 patients scheduled to undergo lumbar puncture (group III) received the same dose of azithromycin 24 h prior to the operation or procedure. Serum from all patients, brain tissue from group I, aqueous humor from group II, and cerebrospinal fluid from group III were assayed for azithromycin concentration. The mean concentrations of azithromycin in brain tissue 24, 48, 72, and 96 h after administration were 2.63 +/- 2.58, 3.64 +/- 3.81, 0.74 +/- 0.37, and 0.41 micrograms/g, respectively. In contrast, the concentrations of azithromycin in cerebrospinal fluid and aqueous humor of the eye were very low or undetectable. Therefore, these data show that azithromycin appears to be widely distributed into brain tissue but not into cerebrospinal fluid or aqueous humor of the eye.

Adolescent↗
PubMed1988

Prostaglandin F2 alpha-1-isopropylester lowers intraocular pressure without decreasing aqueous humor flow.

Using fluorophotometry, we performed a randomized, dose-response study of the effects of a prostaglandin derivative on aqueous humor flow. Prostaglandin F2 alpha 1-isopropylester, 0.224 micrograms, 0.448 micrograms, and 1.120 micrograms, in saline with polysorbate 80 was instilled into one eye of 20 subjects in three separate dose studies. Polysorbate 80 in saline was instilled in the fellow eye as a control. The drug had no measurable effect on aqueous humor flow or corneal endothelial permeability. Intraocular pressure measured eight hours after administration of the highest dose, 1.120 micrograms, was 20% lower in the treated eye as compared to the fellow eye (P less than .001).

Adult↗
PubMed1994

Dominance of activated T cells and interleukin-6 in aqueous humor in Vogt-Koyanagi-Harada disease.

PURPOSE: To determine the immunopathologic role of the lymphocytes and lymphokines in aqueous humor (AH) of patients with Vogt-Koyanagi-Harada disease (VKH). METHODS: The distribution of leukocyte subsets in the peripheral blood and AH was examined using fluorescein isothiocyanate-conjugated monoclonal antibodies. The levels of lymphokines, such as interleukin-2 (IL-2) and interleukin-6 (IL-6), in the sera, AH, and cerebrospinal fluid from the patients with VKH were determined using an enzyme-linked immunosorbent assay. RESULTS: T cells constituted the majority of lymphocytes within AH. The value for CD4+ cells (helper/inducer T lymphocytes) in AH was 51.7% +/- 14.9% (mean +/- SD) and that for CD8+ cells (cytotoxic/suppressor T lymphocytes) was 31.1% +/- 13.0%. The percentage of HLA-DR+ cells (B lymphocytes, monocytes, macrophages, and activated T lymphocytes) in AH (50.8% +/- 24.9%) significantly exceeded (P < 0.001) that in blood (13.1% +/- 4.2%). The percentage of CD8+ cells in AH from three patients with the delayed type of VKH rose during their clinical course. The level of IL-6 was significantly elevated in AH from the patients with VKH. The level of IL-6 in AH correlated with the number of lymphocytes in AH, and it reflected the severity of the inflammatory response in AH of patients with VKH. The level of IL-2 in the sera, AH, and cerebrospinal fluid was in the normal range. CONCLUSIONS: Aqueous humor lymphocytes from the patients with VKH were more activated than were peripheral blood lymphocytes. IL-6 may play an important role as an inflammatory mediator in VKH. It may be useful to analyze the lymphocyte subsets and the levels of lymphokines, especially of IL-6, at the site of inflammation in uvea to improve the criteria for assessing the prognosis of VKH.

Adult↗
PubMedDate not supplied

Noninvasive glucose monitoring of the aqueous humor of the eye: Part I. Measurement of very small optical rotations.

We have described the concept of using the aqueous humor glucose as a measure of the blood glucose concentration, with a view to developing a noninvasive glucose monitor for diabetic individuals. We have conceived of a scleral lens that houses a light source, polarizers, other electro-optic units, and a light detector, and which measures the optical rotation of the aqueous humor continuously. We have built an optical bench mock-up of the glucose sensor and assessed the limits of its capabilities. We have described a physical method, employing the Faraday effect, that modulates the incident light and uses a compensator to introduce a feedback mechanism giving a null-point technique capable of measuring extremely small rotations with an accuracy of 0.4 s of arc. We have used this and have measured the optical rotations of glucose solutions from 0.02 to 0.1%, and have demonstrated linearity in both cases. Miniaturization of the technique is discussed.

Animals↗