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PubMedDate not supplied

Detection of HIV-RNA in aqueous humor and subretinal fluid in an HIV carrier with rhegmatogenous retinal detachment.

BACKGROUND: Although human immunodeficiency virus (HIV)-related ocular complexes are commonly observed in acquired immune deficiency syndrome (AIDS) patients, it has not been previously reported that HIV had already invaded the ocular tissues of HIV carriers. CASE: A 56-year-old woman was diagnosed as having rhegmatogenous retinal detachment with a retinal tear in the 6-o'clock position in her right eye. No signs of ocular manifestations except the retinal detachment were observed. A blood examination revealed that she was already infected with HIV-1, and she was categorized as an HIV carrier. OBSERVATIONS: Aqueous humor and subretinal fluid samples were obtained at the time of surgery for rhegmatogenous retinal detachment. Reverse-transcription polymerase chain reaction and Southern blotting at three regions of the HIV, LTR, gag, and env, confirmed the HIV infection in both aqueous humor and subretinal fluid. During the approximately 2-year follow-up after surgery, the patient did not show any signs of retinitis, uveitis, or other ocular manifestations. CONCLUSIONS: This is the first report to reveal that HIV can invade the eye in the early stage of HIV infection. This infection may be related to HIV-related ocular complexes, which suppress the local immunological response.

Aqueous Humor↗
PubMed2002

Forskolin upregulation of NOS I protein expression in porcine ciliary processes: a new aspect of aqueous humor regulation.

BACKGROUND: To determine whether nitric oxide synthase (NOS) protein expression can be modulated by forskolin in porcine ciliary processes. METHOD: Western blot analysis using mouse monoclonal antibodies against NOS I (neuronal NOS or nNOS), NOS II (macrophage NOS or macNOS), and NOS III (endothelial NOS or eNOS) was performed in porcine ciliary processes. Expression of NOS I and II was also assessed in the presence or in the absence of 1 microM forskolin exposure (4 and 24 hours). RESULTS: All three NOS isoforms could be detected in isolated porcine ciliary processes. Protein expression for NOS I was about 6 times higher than for NOS III and 15 times higher than for NOS II. In comparison to controls, after forskolin exposure, NOS I protein expression was increased by about 1.5-fold. No change could be observed in NOS II protein expression after forskolin exposure. CONCLUSIONS: Nitric oxide is involved in transepithelial fluid transport of different organs (lung, kidney, colon, etc.) and is suspected to play a role in ciliary processes by modulating the aqueous humor production. The present study indicates that forskolin (which increases cAMP production) modulates NOS I protein expression in isolated porcine ciliary processes. These results suggest that selective inhibition of NOS I could be tried for reducing aqueous humor production. The clinical relevance requires further investigations.

Animals↗
PubMed2004

Anti-inflammatory effects of alpha-melanocyte-stimulating hormone against rat endotoxin-induced uveitis and the time course of inflammatory agents in aqueous humor.

PURPOSE: We examined the effects of the immunosuppressive neuropeptide alpha-melanocyte stimulating hormone (alpha-MSH) on rat endotoxin-induced uveitis, and to measure the expression of inflammatory cytokines and chemokines with and without the alpha-MSH treatment over the course of the disease. METHODS: We injected Lewis rats once with Salmonella typhimurium lipopolysaccharide (LPS) to induce uveitis. The rats were given intravenous injections of 250, 500 or 1000 microg of alpha-MSH. The eyes were examined over the next 24 h for inflammation. Aqueous humor was collected 6, 12 and 24 h after endotoxin injections and the number of infiltrating cells were counted in anterior chamber. In addition, we assayed the concentration of protein, nitric oxide, TNF-alpha, IL-6, MCP-1 and MIP-2. RESULTS: Rats injected with alpha-MSH showed a significant decrease in the number of infiltrating cells in anterior chamber. Moreover, alpha-MSH-treated rats with endotoxin-induced uveitis (EIU) showed significantly lower concentrations of protein, nitric oxide, proinflammatory cytokines and chemokines in their aqueous humor. Even the early stages of EIU were suppressed by the injection of alpha-MSH. CONCLUSIONS: Our results demonstrate that the immunosuppressive neuropeptide alpha-MSH inhibits the early induction events of endotoxin-induced inflammation in the eye; therefore, suppresses the subsequent infiltration of cells and intraocular production of inflammatory cytokines and chemokines in eyes. alpha-MSH has a possibility of being a therapeutic strategy for anterior uveitis.

Animals↗
PubMed1975

Penetration of fluorometholone into the cornea and aqueous humor.

In each of the experimental conditions studied, fluorometholone penetrated into the cornea and aqueous humor following topical administration of a standard drop. The amount of drug measured in each location was less than that previously documented for dexamethasone and prednisolone preparations. In contrast to these more conventional steroids, the ocular penetration of fluorometholone appeared to be unaffected by the presence or absence of the corneal epithelium or of intraocular inflammation.

Administration, Topical↗
PubMed1999

Trabecular outflow facility and formation rate of aqueous humor during anesthesia with sevoflurane-nitrous oxide or sevoflurane-remifentanil in rabbits.

UNLABELLED: In the present study, we examined the effect of sevoflurane and remifentanil on intraocular pressure (IOP) and fluid dynamics. Twenty-eight rabbits were anesthetized with halothane, and IOP was measured via a 25-gauge needle in the anterior chamber. Rabbits were then assigned to one of four groups, and halothane was replaced with sevoflurane 1% (n = 7), 2% (n = 7), 3% (n = 7), or 1% + remifentanil 0.65 microg kg(-1) x min(-1) i.v. (n = 7). In all groups, a series of intraocular infusions was made into the anterior chamber, and IOP, trabecular outflow facility, the rate of aqueous humor formation, and intraocular compliance were determined. With sevoflurane only, intraocular compliance decreased (55 +/- 14, 39 +/- 22, 31 +/- 17 nL/mm Hg; P < 0.05) as the concentration of sevoflurane increased. With sevoflurane 1% + remifentanil, intraocular compliance was significantly increased (100.1 +/- 30.5 nL/mm Hg; P < 0.05) compared with sevoflurane 1%, 2%, or 3%. Trabecular outflow facility, rate of aqueous humor formation, and IOP did not differ among groups, and IOP was similar to values obtained during halothane anesthesia. IMPLICATIONS: The dose-related effects of sevoflurane on intraocular compliance did not produce significant intraocular pressure differences. Adding remifentanil to sevoflurane increased intraocular compliance. Sevoflurane or sevoflurane + remifentanil causes a decrease in intraocular pressure compared with the average of previously reported values in awake rabbits, and the magnitude of the decrease is similar to that previously reported in rabbits anesthetized with ethyl urethane, pentobarbital, or halothane alone or in combination with propofol, cocaine, or lidocaine.

Anesthesia↗
PubMed2004

In vivo passage of albumin from the aqueous humor into the lens.

PURPOSE: To determine if albumin, the major protein component of the aqueous humor, passes into the lens in vivo. METHODS: Rat albumin was covalently-labeled with Alexa 488 fluorophore, purified by gel permeation chromatography, then injected into the aqueous chamber of living rats. At 5 min postinjection, lenses were removed and analyzed by HPLC gel permeation chromatography, confocal microscopy, and immunogold electron microscopy. RESULTS: At 5 min postinjection, HPLC analysis detected measurable amounts of Alexa-labeled albumin in the lens. The results were confirmed by confocal microscopy, which showed passage into epithelial and cortical fiber cells. Immunogold electron microscopy using antibody to the Alexa fluorophore demonstrated intracellular location of the Alexa-albumin complex. CONCLUSIONS: In vivo, significant amounts of albumin pass from the aqueous chamber into cells of the lens, consistent with a possible physiological role for this process involving passage of metabolites into the lens.

Animals↗
PubMed1987

Screening cornea donors for antibodies against human immunodeficiency virus. Efficacy of ELISA testing of cadaveric sera and aqueous humor.

Coded cadaveric sera from 35 patients with acquired immunodeficiency syndrome (AIDS), from 45 cadavers at high risk of human immunodeficiency virus (HIV) infection, and from 262 cadavers without known signs or risk of AIDS were assessed using three commercially available enzyme-linked immunosorbent assays (ELISA) kits and Western blot analysis. Greater than 94% sensitivity and 99% specificity was achieved with each of the ELISA test kits using cadaveric sera. The Western blot method gave 97.1% sensitivity compared with the autopsy-proven diagnosis of AIDS. Positive results were obtained on sera from AIDS cadavers even if the time of blood draw was delayed 35 hours from death and the time of sera preparation was delayed up to 176 days. False-negative or false-positive ELISA results did not appear to correlate with hemolysis or any parameter of sera preparation. In contrast to the high sensitivity in testing sera, only 16 to 26% of aqueous humor samples from AIDS cadavers were ELISA-positive and 79% were positive by Western blot. These results indicate that three commercially available ELISA test kits are an effective means of screening cadaveric sera for antibodies to HIV, but that aqueous humor cannot be reliably substituted for cadaveric sera to screen potential cornea donors by an ELISA assay.

Acquired Immunodeficiency Syndrome↗
PubMed1980

Aqueous humor outflow in beagles with inherited glaucoma: constant pressure perfusion.

Determination of facility of aqueous humor outflow (C), using constant pressure perfusion, was performed in vivo in normal dogs and in Beagles with inherited glaucoma at different stages of the disease process. Measurements were taken at 10 mm of Hg increments of intraocular pressure (IOP) from 10 to 50 mm of Hg IOP in the controls and to higher levels of IOP, as needed, to obtain 3 consecutive intervals in which perfusion was required in glaucomatous animals. In normal dogs, C increased slightly as IOP increased to a maximum of 0.22 at 50 mm of Hg. In glaucomatous dogs, C was significantly (P = 0.001) reduced compared with the value in the controls, with a maximum value of 0.09 at 50 mm of Hg.

Animals↗
PubMed2004

Concentration of transforming growth factor beta2 in aqueous humor.

The total transforming growth factor (TGF) beta(2) concentration in the anterior chamber aqueous humor of 96 cataract patients with ages ranging from 17 to 88 years was measured using ELISA to investigate the changes that occur with age, difference of axial length, difference of localization of opacification of the cataractous lens and complications with other eye diseases. It was found that the total TGF-beta(2) concentration (1) decreases with age, (2) shows slight changes with axial length, (3) has slight changes with difference of localization of opacification, (4) is significantly high in patients with concurrent open-angle glaucoma (p < 0.05), (5) is high in patients with complicating diabetes who have undergone panretinal photocoagulation for diabetic retinopathy (p < 0.05) and (6) is low in patients with atopic cataracts. There have been several reports on point 4 above, but none to date of the other points. These findings provide useful information on the intraocular activity of TGF-beta(2).

Adolescent↗
PubMed1983

Capillary endothelial cell migration: stimulating activity of aqueous humor from patients with ocular cancers.

In double-masked studies, various concentrations of aqueous humor (AH) from 157 patients (208 samples) with ocular cancers, nonmalignant ocular lesions, and normal eyes were added to bovine capillary endothelial (BCE) cells plated onto gold-coated cover slips. The phagokinetic tracks made by 100 cells at each concentration were traced, and the mean area of migration plus or minus the standard error of the mean was determined. Data are expressed as the percentages of increase in mean track area made by 100 cells incubated in medium that contained AH samples beyond the mean area of 100 cells incubated in medium alone. The percentage increases in migration-stimulating activity were as follows: a) malignant ocular disease--retinoblastoma (30 samples), 34 +/- 2; malignant melanoma (55 samples), 37 +/- 3; b) nonmalignant ocular disease--cataracts, glaucoma, pseudoglioma, and diabetic retinopathy (36 samples), 14 +/- 2; c) control AH--no ocular disease (51 samples), 9 +/- 1; normal eyes and systemic cancer (36 samples), 38 +/- 6. The percentage increase in endothelial cell migration was as great in cases of systemic cancer as it was in cases of ocular cancer. The endothelial cell migration-stimulating activity in AH from patients with intraocular cancers was significantly higher than the levels in the other groups of patients having no systemic cancer (P much less than .001). In addition, when the results were compared in the control group and the group with benign ocular disease, no significant differences were detected (P greater than .01).

Animals↗
PubMed2006

Decrease in reducing power of aqueous humor originating from glaucomatous rabbits.

AIM: To evaluate changes in the reducing power of aqueous humor (AH) with cyclic voltammetry (CV) and HPLC-EC. METHODS: NZW Rabbits exhibiting a sporadic mutation causing bilaterally buphthalmus eyes were set for intra ocular pressure (IOP) and eye size measurements. AH was obtained under anesthesia, from congenital glaucomatic rabbits (CGR, n=6) and age-matched controls (CON; n=6). The AH samples were analysed by CV and HPLC-EC. RESULTS: CGR IOP was found to be significantly higher than in CON (33.5+/-1.1 and 14.2+/-1.0 mmHg, respectively), eye size was 18.25 and 13.9 cm, respectively. CV analysis revealed two anodic currents representing two groups of low molecular weight antioxidant (LMWA). The two anodic potentials were equal for the two tested groups, indicating the same components of LMWA. The first anodic current of CGR was only 30% of the CON rabbits (2.11 vs7.17 microA/mg protein, t-test: P<0.05). As the main hydrophilic components of the first anodic current are known to be uric acid (UA) and ascorbic acid (AA), they were analysed for exact content by HPLC-EC. UA and AA levels were significantly lower in the CGR group (UA: 17.1+/-3.2 and 189.1+/-75.70 microM/mg, AA: 1.1+/-0.3 and 4.8+/-2.0 microM/mg protein respectively). CONCLUSIONS: Changes in the reducing power, as indicated by CV analysis, of CGR AH, is probably a result of chronic oxidative stress caused by the pathology. The differences in the first anodic wave are mainly due to a fall in the concentration of UA and AA.

Animals↗
PubMed2000

Comparison of PCR detection methods for B1, P30, and 18S rDNA genes of T. gondii in aqueous humor.

PURPOSE: Comparison of polymerase chain reaction (PCR) amplification of three Toxoplasma gondii genes in aqueous humor. METHODS: Nested PCRs carried out using published methods were optimized for maximum sensitivity and specificity. Five pairs of oligonucleotide primers, directed against the B1, P30, and ribosomal genes, were used and compared to determine which sequences were most effective in detecting T. gondii DNA. Methods were developed with DNA templates in water and were subsequently applied to both normal and inflamed aqueous. RESULTS: After one round of PCR amplification, P30 and ribosomal primers were able to detect 1 pg genomic T. gondii DNA. However, those directed against the B1 gene were able to detect 50 fg (approximately single tachyzoite). This level of sensitivity was also achieved using the P30 primers after a second round of PCR; however, only primers based on the B1 gene maintained this level of sensitivity in both normal and inflamed aqueous. B1-specific primers did not amplify sequences from fungal, bacterial, or human lymphocyte DNA. The sensitivity of T. gondii detection using B1 gene-specific primers was not compromised when large amounts of human lymphocyte DNA were present, and application to an ocular sample or retinal section from patients with toxoplasma chorioretinitis was successful in confirming the presence of T. gondii DNA. CONCLUSIONS: The B1 PCR protocol appears to be the most sensitive protocol in the detection of T. gondii DNA and has been successful in identification of T. gondii DNA in ocular fluids and retinal sections. This provides direct evidence of the presence of T. gondii within the eye and may therefore help in the management of toxoplasma retinochoroiditis.

Animals↗
PubMed1976

[Study of the composition of aqueous humor in normal subjects by means of automatic analytical technics].

Five new constituents in the aqueous humour were measured as part of a study on the constitution of the aqueous in normal subjects; urea, glucose, phosphorus, calcium and the carbonates and bicarbonates representing the alkaline reserve. Each of these constituents were measured by an automatic method using the Technicon auto-analyser, a similar sample of aqueous humour serving in some cases for simultaneous measurement of several constituents. The principles of the reaction, the Manifold used and the results obtained are reported for each of these. The latter were studied more particularly as a function of age on the one part and also a function of the serum levels of the same constituent. This simultaneous study establishes a relationship between the aqueous humor and the plasma which is compared with preceding reports in the literature and with results obtained more often in animals. Several important physiological and physiopathological considerations arise from these findings.

Adult↗
PubMed1989

Flow of aqueous humor in the canal of Schlemm.

A mathematical model is presented for the flow of aqueous humor in Schlemm's canal in the eye. The model introduces a canal segment between two collector channels as a rectangular channel with porous upper wall. Two cases have been considered in the model: (I) the inner porous wall of the canal is rigid; (II) the inner wall is collapsible. Analytical solution of the governing equation in case I is straightforward, whereas the nonlinear equation in case II is solved by an iterative procedure. Aqueous fluid pressure and flow profiles in the proposed model are drawn, and the effects of important parameters on these profiles are brought out and discussed. It is concluded that for case I, resistance to aqueous flow is influenced by the filtration constant of the trabecular and endothelial meshwork and that narrowing of the canal reduces outflow. In case II, an increase in intraocular pressure (IOP) or compliance coefficient of the canal inner wall increases the collapse of the canal, which offers increased resistance to flow resulting in the decreased flow whereas increasing filtration constant facilitates aqueous outflow. These theoretical results suggest that increased IOP or decreased rigidity of the inner wall may contribute to the development of increased resistance as observed in some cases of glaucoma and that increasing values of filtration constant may contribute to the facility of outflow increase.

Animals↗
PubMed2004

Prostaglandins F2alpha and E2 in aqueous humor of patients with cataract surgery.

To understand the role of prostaglandins F(2alpha) and E(2) in aqueous humor under the normal condition, their concentrations were measured by enzyme immunoassay in aqueous fluid obtained from either eye of 60 patients during cataract surgery and correlated with clinical factors as the age and intraocular pressure. The concentrations of prostaglandin F(2alpha) in the aqueous of all patients were below the level of detection. The concentrations of prostaglandin E(2) in the aqueous were below the level of detection in 37 patients while ranged from 9 to 48 pg/mL (median, 31) in 23 patients. The levels of prostaglandin E(2) did not have correlation with the age of the patients or the intraocular pressure of the eyes. In conclusions, the concentrations of prostaglandin E(2) were apparently higher than the concentrations of prostaglandin F(2alpha) in the aqueous. This study could not prove the relationship between prostaglandin levels and the intraocular pressure or the age.

Adult↗