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At least 19 recordsLinked to original sources
PubMed1978

Perfusate effects upon resistance to aqueous humor outflow in the rhesus monkey eye. A comparison of glutathione-bicarbonate Ringer's solution to pooled aqueous humor as perfusate.

In vivo perfusion of the anterior chamber of normal rhesus monkeys with pooled rhesus aqueous humor gives an initial total facility of 0.48 +/- 0.08 (+/-S.E.) microliter/min/mm Hg. With continued intermittent perfusion for 2 hr this value increased only slightly to 0.57 +/- 0.10 microliter/min/mm Hg. Perfusion of the paired eyes of the same monkeys with glutathionebicarbonate Ringer's solution gives an initial total facility of 0.55 +/- 0.08 microliter/min/mm Hg. This value increased to 1.21 +/- 0.15 microliter/min/mm Hg with continued intermittent perfusion. Thus aqueous is a satisfactory perfusate for experiments requiring prolonged stability of the eye, but glutathione-bicarbonate Ringer's solution is not a satisfactory substitute perfusate. Neither addition of physiologic amounts of ascorbic acid to the buffered salt solution nor careful modification of the pH of the solution to the physiologic level prevented the increase of total facility it produces when used as a perfusate. A reversible, fast-phased small-magnitude increase in total facility was noted in eyes perfused with either perfusate. It is speculated this is caused by neural mechanisms for intraocular pressure control.

Animals↗
PubMed1979

Rhesus monkey aqueous humor composition and a primate ocular perfusate.

The composition of rhesus monkey aqueous humor has been studied in large-volume, pooled samples. Replicate determinations of the concentrations of a number of constituents have been carried out for both aqueous humor and serum from large veins by means of automatic analyzing equipment. Since aqueous humor has been obtained by anterior chamber paracentesis, it is a mixture of anterior and posterior chamber aqueous. When compared to serum, the pooled aqueous contains an excess of chloride, bicarbonate, ascorbate, lactate, uric acid, and several neutral amino acids. Rhesus monkey aqueous humor is deficient in calcium, urea nitrogen, phosphates, glucose, protein, creatinine, iron, bilirubin, cholesterol, triglycerides, a number of serum enzymes, acidic and basic amino acids, and several neutral amino acids. Sodium, potassium, magnesium, and two neutral amino acids (cysteine and valine) are of equal concentration in aqueous humor and serum. Glutathione concentration is very low in both aqueous humor and serum. Pooled rhesus monkey aqueous humor and serum are isosmolar, with measured osmolality being about 303 mOsm. Based upon the chemical analysis, a new solution has been formulated to substitute for primate aqueous humor during anterior ocular perfusion. This new solution causes very little change in the physiologic integrity of the outflow pathways during prolonged, repeated perfusion. In this respect, its effects are very similar to those of pooled rhesus monkey aqueous humor during perfusion of rhesus monkey eyes. In contrast, perfusion of rhesus monkey eyes with glutathione-bicarbonate-Ringer's solution has been shown to cause progressive increase of the total facility. To minimize physiologic alterations during operative procedures, a solution similar to this new one could be formulated for irrigation of the inside of the human eye.

Animals↗
PubMed1979

Lactate dehydrogenase levels and isozyme patterns. Measurements in the aqueous humor and serum of retinoblastoma patients.

Lactate dehydrogenase (LDH) activity was determined in 24 cases of histologically proved retinoblastoma. The mean level was 1,825 IU/L, with a range of 10 to 15,920 IU/L. Twenty-two patients had elevated aqueous humor LDH levels. In two, the aqueous humor level was within the normal range. Student's t testing showed a highly significant difference between cataract and retinoblastoma aqueous humor. The retinoblastoma aqueous humor to blood ratio ranged from 0.045 to 58,529--not a good index of retinoblastoma. Isozyme patterns of retinoblastoma aqueous humor were statistically similar to those of normal cataract aqueous humor. The serum LDH level of cataract patients was not statistically different from that of retinoblastoma patients. The LDH 5/LDH 1 ratio of retinoblastoma aqueous humor ranged from 0.042 to 27.05--not a good index of retinoblastoma, as 28 of 34 aqueous samples of cataract patients had LDH 5 greater than LDH 1. Ten of 13 retinoblastoma patients had aqueous humor LDH 5 greater than LDH 1. The best index of the presence or absence of retinoblastoma is the total aqueous humor LDH level.

Aqueous Humor↗
PubMed1978

Cefamandole levels in primary aqueous humor in man.

We administered cefamandole nafate to 69 patients before cataract extraction and assayed serum and aqueous humor for antibiotic content at the time of surgery. Average aqueous humor levels of 0.33, 0.59, 0.21, and 0.14 microgram/ml were achieved at one half, one, two and four hours, respectively, after a 1-g intravenous dose. After a 2-g intravenous dose, we found average aqueous humor levels of 1.26, 1.0, 1.57, 0.73, and 0.34 microgram/ml at one half, one, two, four and six hours, respectively. Therapeutic levels in primary aqueous humor effective against common grampositive pathogens were consistently achieved with the 2-g dose, but levels effective against Enterobactereaceae were attained only erratically.

Aqueous Humor↗
PubMed1976

Lipid-laden aqueous humor associated with anterior uveitis and concurrent hyperlipemia in two dogs.

Two dogs with cloudy aqueous humor due to accumulation of lipid and lipoprotein had concurrent hyperlipemia and anterior uveitis. In 1 dog, serum and aqueous humor had similar lipoprotein electrophoretic patterns, and in the other dog, the patterns were different. The therapeutic approach included symptomatic treatment of the uveitis and reduction of dietary fat intake. Clearing of fat from aqueous humor followed control of the uveitis.

Animals↗
PubMed1979

Experimental ciliochoroidal detachment. Effect on intraocular pressure and aqueous humor flow.

Ciliochoroidal detachments were produced in rhesus monkeys by injecting glutathione bicarbonate Ringer's solution, autologous serum, or silicone oil into the anterior suprachoroidal space. Silicone oil detachments, like sham operations, caused a transient 2 mm Hg reduction in intraocular pressure. Detachments with glutathione bicarbonate Ringer's solution or serum caused a 6 mm Hg reduction in intraocular pressure, which normalized in three weeks. Aqueous humor flow in serum-detached eyes was normal, indicating that the hypotonia does not result from reduced aqueous humor formation. Blood was present in Schlemm's canal in most eyes with hypotonia, which suggests that hypotonia is not the result of enhanced conventional aqueous humor outflow. Therefore, it is postulated that hypotonia might result from enhanced aqueous humor outflow from the anterior chamber into the suprachoroidal space and out of the eye through the emissarial channels of the sclera (uveoscleral outflow).

Animals↗
PubMed1979

[The determination of IgE in human aqueous humor in a case of intraocular parasitosis (ophthalmomviasis interna) (author's transl)].

A case of intraocular myasis is here reported, as well as the difficulties of diagnosis--mostly too late--of this disease, which is rare in Europe and the northern hemisphere and which leads, almost invariably, to functional or even anatomical loss of the eye.--The determination of IgE in human aqueous humor (ah) and corresponding serum (s) by means of the ultrasensitive and quite simple PRIST method could represent a possibility of timely diagnosis, and this theoretically too in the case of other, much more frequent oculoparasitosis cases.--A retrospective study of the preoperative aqueous humor of the ophthalmomyiasis case presented here revealed an IgE concentration of 113 U/ml in the aqueous humor, with only 3 U/ml (1 U congruent to 2 ng) in the corresponding serum. A simple serum-IgES-determination would not have permitted the diagnosis--at least not in the case examined--just as little as numeration of eosinophilic granulocytes in blood and/or aqueous humor.

Aqueous Humor↗
PubMed1975

Prostaglandin-like activity in the aqueous humor following alkali burns.

Following application of 20 mul of 2 N sodium hydroxide to the rabbit cornea, the prostaglandin-like activity in the aqueous humor increased from undetectable levels to around 30 ng, per milliliter, a level which was sustained for up to 24 hours. This increase correlated with the previously reported sustained elevation of intraocular pressure following a 20 mul alkali burn. Pretreatment with aspirin or indomethacin virtually abolished the increase in intraocular pressure and elevation of prostaglandin-like activity in the aqueous humor following a 20 mul burn. Marked ocular hypotension following 50 mul and 100 mul sodium hydroxide burns correlated with very low prostaglandin-like activity in the aqueous humor. The low prostaglandin-like activity probably resulted from alkaline hydrolysis of aqueous prostaglandins and massive cellular death in iris and ciliary body tissues.

Alkalies↗
PubMed1979

Fluorescein angiography and changes in aqueous humor protein after argon laser photomydriasis in rabbits.

In brown-eyed and blue-eyed rabbits, irises treated with argon laser photomydriasis (ALP) were studied by using fluorescein angiography and by evaluating the aqueous humor protein concentration. The following results were obtained. Immediately after ALP, a breakdown of the blood-aqueous barrier is demonstrated by a marked influx of fluorescein into the ciliary processes and into the anterior and posterior chambers. The dye flow into the aqueous humor decreases to normal values within 3 days. There is no fluorescein leakage from laser impacts themselves. Peripupillary capillary loops are permanently occluded, but in a few cases, recanalization occurs. Neovascularization did not occur during 56 days of observation. ALP initially leads to a six- to eightfold increase in normal aqueous humor protein concentration, which decays to normal values within 3 days.

Animals↗
PubMed1978

Immunoglobulin E in human aqueous humor and corresponding serum. A physiopathological and clinical study.

The analysis of IgE in aqueous humor yielded an average concentration of 3.4 +/- 0.97 U/ml for 22 cataract patients and 5.5 +/- 3.42 U/ml for five uveitis patients. The IgE level in aqueous humor (IgEa.h.) of the cases examined is most probably, beside hematoocular diffusion of serum IgEs, the result of intra-ocular IgE production. In comparison with (mostly normal) IgEs levels, the IgEa.h. concentration appears relatively elevated, not only with uveitis patients, but also with cataract patients, above all when lenticular opacity is accompanied by other ophthalmic diseases (glaucoma, high myopia, diabetes). This "increase" of IgEa.h. concentration in very probably due to the radioimmunosorbent (RIST) technique employed, the most sensitive method available at the time of the present study. Thus, the calculated IgEa.h. value in the cataractous eyes should be regarded simply as approximate to the normal IgEa.h. concentration. These values are of clinical significance however, since a reference IgEa.h. mean-value is indispensable to the interpretation of pathologically high IgEa.h. levels and ethics do not permit of IgEa.h. determination in healthy eyes. The mean IgEa.h. levels of the delayed-type uveitis and cataract patients examined reveal no significant differences. IgEa.h. determination could make a contribution to the etiological clarification of, for example, immediate-type uveitis cases and intra-ocular parasitosis and serve as an appropriate model to study intra-ocular immunomechanisms.

Adult↗
PubMed1979

Sickled erythrocytes, hyphema, and secondary glaucoma: IV. The rate and percentage of sickling of erythrocytes in rabbit aqueous humor, in vitro and in vivo.

The number of erythrocytes adopting the sickled configuration in rabbit aqueous was determined with a masked counting technique in vitro and in vivo. The percentage of cells that became sickled in aqueous humor was greater than that observed in a control salt solution and in the donor blood itself. Aqueous humor, therefore, can be considered a particularly deleterious medium for erythrocytes having a propensity for sickling. Blood samples from six donors with systemically severe hemoglobinopathies (SC, Sthal, and SS) had relatively high levels of hemoglobin S and, in general, showed faster and more frequent sickling than did blood samples from donors with low levels of hemoglobin S (one SS patient, whose chronic blood transfusion regimen had replaced most of his hemoglobin S with normal hemoglobin, and two AS patients). Even erythrocytes from sickle cell trait cases, however, were capable of sickling when immersed in acqueous humor.

Anemia, Sickle Cell↗
PubMed1979

Cathepsin B and collagenolytic cathepsin in the aqueous humor of patients with Behçet's disease.

Cathepsin B and collagenolytic cathepsin activities were studied biochemically in human aqueous humor. The enzyme activities were found to be significantly high in the aqueous humor of the patients with Behçet's disease, but not detectable in those with senile cataract, retinoblastoma, and maxillar carcinoma. These data suggest that cathepsin B and collagenolytic cathepsin have a certain role in the inflammatory collagenolytic process of Behçet's disease.

Adult↗
PubMed1979

Carcinoembryonic antigen in aqueous humor of patients with primary malignant choroidal melanoma.

Carcinoembryonic antigen levels were simultaneously determined in the aqueous humor and in the plasma of the 3 patients with primary choroidal malignant melanoma undergoing enucleation. An elevated carcinoembryonic antigen level was detected in the aqueous humor of 1 patient with no increase in plasma CEA level. In the other 2 patients no such elevation was found. A local increase of CEA levels produced by the tumor is likely to occur. Further studies are required of CEA levels of patients with primary malignant choroidal melanoma as an aid in diagnosis and treatment of this condition.

Aged↗
PubMed1975

[Quantitative determination of aqueous humor proteins by electroimmodiffusion in an antiserum containing agarosegel (author's transl)].

An exact quantitation of aqueous humor proteins within a few hours can be attained by an modification of the quantitative estimation of the proteins by electrophoresis in agarose gel established by Laurell. The aqueous humor proteins form long immunoprecipitations in agargel. The length of the precipitats is proportional to the concentration. By determination of albumin, coeruloplasmin and transferrin the application can be pointed out.

Albumins↗