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At least 1,045 records · Page 58Linked to original sources
PubMed1984

Aqueous humor cytology of pseudophakic bullous keratopathy.

The long-term effects of the interaction between an IOL and the immune system of the implanted patient are not yet clear. This study presents the results of aqueous humor (AH) cytological analysis of 51 patients undergoing intraocular surgery for cataract, and aphakic (ABK) or pseudophakic bullous keratopathy (PBK). Cataract AH was acellular (N = 8). The mean ABK AH cell count was 8.5 +/- 6.4 cells per high power field (hpf) of cytologically filtered specimens; mean PBK cell count was 30.2 +/- 13.0. If inflamed eyes are defined as those with more than one cell/hpf, a statistically significant greater number of PBK eyes than ABK eyes were inflamed (93% versus 44%, P less than 0.003 chi square). More than 99% of the nucleated cells were mononuclear histiocytes. One PBK patient had many multinucleated giant cells in the AH.

Aphakia, Postcataract↗
PubMed1992

A fluorophotometric study on the aqueous humor dynamics in primary open angle glaucoma.

One hundred and ten eyes in 40 normal persons with no ocular pathology, 20 with ocular hypertension and 50 with primary open angle glaucoma were studied. The value of the aqueous humor flow was obtained and then compared with the different samples and with general (age, sex) and ocular factors (intraocular pressure, tonographic outflow facility, campimeter and disk/cup ratio, among others).

Adult↗
PubMed1981

[Effect of corticoids on protein concentration in rabbit aqueous humor after argon laser surgery of the iris (author's transl)].

A high dose of corticoid premedication was applicated intramuscularly five hours before laser surgery. Following laser coagulation of the pigmented iris the protein concentration in the aqueous humor was measured every hour. The initial increase in protein concentration was found to be lower than in earlier experiments without premedication. In contrast to earlier results without corticoid premedication, the reaction of the untreated contralateral eye was suppressed.

Animals↗
PubMed1982

Penetration of intravenously administered cefoxitin into the aqueous humor of inflamed human eyes.

Intravenous injections of cefoxitin (2-g doses for adults and 40 mg/kg of body weight doses for children) were administered 90 minutes to two hours before surgery. All nine eyes had anterior segment inflammation. Samples of aqueous humor removed during surgery showed a mean cefoxitin concentration of 6.22 micrograms/ml, almost three times the concentration reported in uninflamed eyes. The greater penetration may have been the result of a breakdown in the blood-aqueous barrier. There were no complications.

Adolescent↗
PubMed1997

Effects of adenosine agonists on intraocular pressure and aqueous humor dynamics in cynomolgus monkeys.

The effects of single or multiple topical doses of the relatively selective A1 adenosine receptor agonists (R)-phenylisopropyladenosine (R-PIA) and N6-cyclohexyladenosine (CHA) on intraocular pressure (IOP), aqueous humor flow (AHF) and outflow facility were investigated in ocular normotensive cynomolgus monkeys. IOP and AHF were determined, under ketamine anesthesia, by Goldmann applanation tonometry and fluorophotometry, respectively. Total outflow facility was determined by anterior chamber perfusion under pentobarbital anesthesia. A single unilateral topical application of R-PIA (20-250 micrograms) or CHA (20-500 micrograms) produced ocular hypertension (maximum rise = 4.9 or 3.5 mmHg) within 30 min, followed by ocular hypotension (maximum fall = 2.1 or 3.6 mmHg) from 2-6 hr. The relatively selective adenosine A2 antagonist 3,7-dimethyl-1-propargylxanthine (DMPX, 320 micrograms) inhibited the early hypertension, without influencing the hypotension. Neither 100 micrograms R-PIA nor 500 micrograms CHA clearly altered AHF. Total outflow facility was increased by 71% 3 hr after 100 micrograms R-PIA. In conclusion, the early ocular hypertension produced by topical adenosine agonists in cynomolgus monkeys is associated with the activation of adenosine A2 receptors, while the subsequent hypotension appears to be mediated by adenosine A1 receptors and results primarily from increased outflow facility.

Adenosine↗
PubMed1997

[A short-term clinical study on a new aqueous humor drainage implant for refractory glaucoma].

OBJECTIVE: To investigate the therapeutic effect of a new aqueous humor drainage implant made in China for treatment of refractory glaucoma. METHODS: The implant was designed by ourselves and manufactured by Beijing Rubber Products Design & Research Institute. From July 1993 to September 1995, we observed 40 cases (41 eyes) with refractory glaucoma treated with the implantation surgery, including neovascular glaucoma (NVG) 16 eyes, non-neovascular glaucoma (NNVG) 25 eyes. RESULTS: The mean period of postoperative follow-up was 9.2 (range 3-27 months) months, the IOP was lowered from preoperative 7.20 +/- 1.51 kPa to postoperative 2.40 +/- 1.33 kPa in NVG group and from preoperative 6.27 +/- 1.07 kPa to postoperative 2.00 +/- 2.93 kPa in NNVG group. The success rate was 81% in NVG group and 84% in NNVG group. The common postoperative complications were flat anterior chamber, hyphema, choroidal detachment and so on. CONCLUSIONS: Our newly designed aqueous humordrainage implant provides an economic implant in China. The method of implantation is simple, is one of the effective methods for treatment of refractory glaucoma and can be widely used in clinics.

Adult↗
PubMed1993

Flow cytometric study of anterior chamber aqueous humor after neodymium: yttrium aluminum garnet laser iridotomy.

Laser iridotomy is a safe and effective treatment of pupillary-block glaucoma; however, increased intraocular pressure (IOP) may occur after the procedure. A flow cytometric study of aqueous humor was done 1.5 hours after neodymium: yttrium aluminum garnet laser iridotomy in 20 eyes. This sensitive and precise method did not reveal an apparent correlation between the degree of postoperative IOP spike and the amount of inflammatory cells or cellular debris induced by laser iridotomy. Although slit-lamp examination showed many "cells" in the anterior chamber in most after laser iridotomy, DNA histography found only scanty chromatin coating cells. We believe the so-called cells observed using slit-lamp biomicroscopy might not all be real cellular aggregates but rather aggregates of protein or fibrin in some situations.

Acute Disease↗
PubMed1999

Detection of feline herpesvirus-specific antibodies and DNA in aqueous humor from cats with or without uveitis.

OBJECTIVE: To determine whether uveitis in cats was associated with intraocular production of feline herpesvirus type 1 (FHV-1)-specific antibodies or with detection of FHV-1 DNA in aqueous humor (AH). ANIMALS: 44 cats with idiopathic uveitis, 29 cats with uveitis attributed to Toxoplasma gondii infection, 13 FHV-1 seropositive cats without uveitis, and 9 FHV-1 seronegative cats without uveitis. PROCEDURE: ELISA were used to detect FHV-1-specific antibodies and total IgG antibodies in serum and AH, and the Goldmann-Witmer coefficient (C-value) for intraocular antibody production was calculated. A polymerase chain reaction assay was used to detect FHV-1 DNA in AH. RESULTS: FHV-1 seroprevalence among cats with uveitis was not significantly different from seroprevalence among cats without uveitis. Intraocular FHV-1 antibodies were never detected in cats without uveitis. Significantly more cats with idiopathic uveitis (22/44) or with toxoplasmic uveitis (11/29) had evidence of intraocular antibody production (C-value > 1) than did cats without uveitis. Only cats with idiopathic uveitis had FHV-1 C-values > 8. Among cats with evidence of intraocular antibody production, cats with idiopathic uveitis had a significantly higher median FHV-1 C-value (9.61) than did cats with toxoplasmic uveitis (2.56). Overall, FHV-1 DNA was detected in AH from 12 cats, 11 of which had uveitis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that FHV-1 can infect intraocular tissues of cats and that intraocular FHV-1 infection may be associated with uveal inflammation in some cats.

Alphaherpesvirinae↗
PubMed2004

Chemokines and gelatinases in the aqueous humor of patients with active uveitis.

PURPOSE: To investigate the involvement of the chemokines CXCL10/IP-10, CXCL11/I-TAC, CXCL8/1L-8, CXCL6/GCP-2, CCL3/MIP-1alpha, and CCL18/PARC, and gelatinases A and B in uveitis. DESIGN: Prospective, experimental, case-control study. METHODS: Aqueous humor samples from 30 patients with active uveitis, and 14 control patients and paired serum samples were assayed for chemokines with specific enzyme-linked immunosorbent assays (ELISAs) and for gelatinase levels by quantitative zymography. RESULTS: In control AH, none of the chemokines was detected. Gelatinase A was detected in all samples, and gelatinase B was detected in only one sample. In patients with uveitis, IP-10 was detected in all AH samples, whereas I-TAC, IL-8, GCP-2, MIP-1alpha, and PARC were detected in three, 16, six, two, and 12 samples, respectively. IP-10 levels were significantly higher in AH samples than those of serum (P =.006). Gelatinase A was detected in 29 AH samples and gelatinase B was detected in 26 samples. Gelatinase A levels were significantly higher in AH samples from patients than those of controls (P <.0001). In 11 AH samples, gelatinase B was detected in complex with lipocalin (NGAL). Disease activity correlated significantly with the levels of IP-10 (r =.627; P <.0001), gelatinase A (r =.508; P =.002), gelatinase B (r =.685; P <.0001), and NGAL-gelatinase B complex (r =.595; P <.0001). CONCLUSIONS: These data suggest a pathogenic role of the T lymphocyte chemoattractant IP-10 and gelatinases in the recruitment and activity of T cells into the eye in patients with uveitis and in the pathogenesis of uveitis.

Adolescent↗
PubMed2003

Nitric oxide and cyclic GMP enhance aqueous humor outflow facility in rabbits.

PURPOSE: Nitric oxide (NO) may control intraocular pressure (IOP)-regulating mechanisms physiologically and in ocular diseases such as glaucoma. The aim of the present study was to clarify whether an increase in aqueous humor outflow facility could explain the IOP-lowering effect of the NO/cyclic GMP pathway we recently described. METHODS: Test compounds were administered to anesthetized rabbits (New Zealand White, n = 6) intracamerally (5 microl) in the following doses: nitrosocaptopril 12.3 microg, captopril 10.9 microg, sodium nitroprusside (SNP) 13.1 microg and 8-Br-cGMP 22.3 microg. Outflow facility (C) was determined by the two-level constant pressure infusion method. Outflow facility, C( 1) and C(2), was measured at lower and higher pressure levels, respectively. RESULTS: Outflow facility was increased after treatment with SNP (increase in C in the experimental eye as compared to the control eye C( 1) 80% and C(2) 74%), nitrosocaptopril (C(1) 69% and C(2) 64%) and 8-Br-cGMP (C(1) 35% and C(2) 33%). Captopril had no effect on outflow facility (C(1) -12% and C(2) 2%). Blood pressure was not affected by the drugs. CONCLUSIONS: We conclude that enhancement of outflow facility by nitrosocaptopril, SNP and 8-Br-cGMP, their second messenger derivative, at least partly explains the IOP-lowering effect of NO releasing compounds.

Animals↗
PubMed1991

Penetration of hydrogen peroxide from contact lenses or tear-side solutions into the aqueous humor.

Contact lenses were soaked in hydrogen peroxide (H2O2) solutions of 1 to 20 mM (34 to 680 ppm) and placed on isolated rabbit corneas to determine whether H2O2 could penetrate across the tissue into the artificial aqueous humor used to perfuse the endothelial surface. Corneas with intact epithelium allowed no H2O2 to cross into the perfusing fluid even with the lenses containing the highest (20 mM) concentration of peroxide. If the epithelium was removed a transient pulse of H2O2 appeared in the perfusing fluid only from lenses with 10 or 20 mM H2O2. The cornea metabolized H2O2 rapidly (the rate varying with the concentration) and thus the small quantities of H2O2 in the contact lenses (less than 400 nmol at 20 mM) are destroyed before diffusing across the entire thickness of the cornea. When the contact lens was replaced by a 0.8 ml saline containing H2O2, and renewed every 15 min, H2O2 crossed the intact cornea to the perfusing fluid when its concentration at the epithelium was between 3 and 4 mM. Should such larger quantities be presented to the epithelium (for example, in eye drops) the concentration, volume, and duration of exposure will determine whether H2O2 enters the anterior chamber. It is concluded that in the clinical situation of typical contact lens use in an eye with intact epithelium neither the corneal endothelium nor other intraocular tissues will be damaged by residual concentrations of H2O2 up to 680 ppm, whether in single or daily events.

Animals↗
PubMed1996

Apoptosis-related fas antigen on memory T cells in aqueous humor of uveitis patients.

To investigate the role of lymphocytes in the pathogenesis of uveitis, we analyzed the expression of memory markers, CD29 and CD45RO antigens, and apoptosis-related Fas antigen on T lymphocytes in the aqueous humor (AH) and peripheral blood (PB) from patients with uveitis. Using three-color flow cytometry, we assessed the number of T lymphocyte subsets that stained with fluorescence-conjugated anti-CD3, CD4, CD8, CD29, CD45RA, CD45RO, HLA-DR, and Fas monoclonal antibodies in the AH and PB from 19 patients with active uveitis who were diagnosed as having sarcoidosis, Vogt-Koyanagi-Harada disease, HLA-B27+ uveitis, or idiopathic uveitis. Cells from AH and PB were evaluated by light and electron microscopy before and after 6 h of incubation. The majority of lymphocytes in AH but not in PB, were CD3+HLA-DR+ (activated) T cells. The percentage of CD4+ lymphocytes was significantly higher in uveitic AH than in PBL (P < 0.01). While the percentage of CD4+ CD45RA+ (naive) cells within T cells was much lower in uveitic AH than in PB, the percentage of CD4+CD29+ or CD4+CD45RO+ (memory) cells was significantly higher in uveitic AH than in PBL (P < 0.01). Fas antigen was expressed preferentially on memory cells in uveitic AH. Apoptosis of cells in the AH was observed by microscopically following after incubation with no stimulation. Lymphocytes from the AH of patients with uveitis were more activated than those from PB. The majority of T lymphocytes from uveitic AH expressed memory markers and Fas antigen. Results suggest that an increase in the number of Fas+ memory T lymphocytes in AH is involved in the pathogenesis of uveitis.

Adolescent↗
PubMed1986

Intraocular pressure and aqueous humor dynamics in rabbit and primate with d- and 1-adrenergic compounds.

The effects of the d- and 1-isomers of epinephrine and norepinephrine have been determined on intraocular pressure (IOP) in conscious rabbits and rhesus monkeys, and on aqueous humor turnover rate (AHTR) in rabbits. Relatively specific beta-adrenergic antagonists (butoxamine and metoprolol) were used to attempt to modify the responses. The effects on IOP in both species are similar to those of racemic mixtures. The d- and 1-isomers of norepinephrine and epinephrine reduced IOP, and reduced AHTR in rabbits. The d- and 1-isomers of norepinephrine had little effect on IOP in monkeys while d- and 1-epinephrine increased IOP. Metoprolol, a beta 1-antagonist was more effective than butoxamine (beta 2-antagonist) at modifying the effect of the norepinephrine isomers in rabbits.

Animals↗
PubMedDate not supplied

Inflammatory reaction in acute retinal artery occlusion: cytokine levels in aqueous humor and serum.

PURPOSE: To investigate the role of inflammation in acute retinal artery occlusion (RAO). METHODS: Levels of interleukin (IL)-6, IL-8, and tumor necrosis factor alpha (TNF-alpha) were measured in serum (n = 14) and aqueous humor (AqH) (n = 8) samples from patients with RAO. Findings were compared with 24 age- and disease-matched patients, 10 healthy subjects (serum), and 16 patients undergoing cataract surgery (AqH). RESULTS: Patients who arrived early (within 4-6 hours of occlusion) had higher serum IL-8 and IL-6 levels than controls; the IL-6 level in the AqH was lower than that of controls, while the IL-8 level was higher. In seven patients for whom both serum and AqH samples were available, serum IL-6 levels were higher than their corresponding AqH levels in most patients arriving within 10 hours of occlusion, and AqH IL-8 levels were higher than the corresponding serum levels in all but one. TNF-alpha levels were consistently higher in the serum than in the AqH at all time points. CONCLUSIONS: Serum IL-8 and IL-6 and AqH IL-8 are elevated immediately following acute RAO. The early local suppression of IL-6 may be related to ocular immune mechanisms.

Acute Disease↗