摘要:

Neovascular growth into the cornea induced by silver nitrate cauterization is the basis of this experimental model developed to test potential anti-inflammatory drugs for ocular use. Cauterization of the rat cornea with a silver nitrate applicator stick provides the stimulus for neovascularization, which is scored by a #blinded# investigator. Burn stimulus intensity is also scored to substantiate a consistent stimulus among the groups. Compounds showing activity in this model include topical dexamethasone, prednisolone, ticabesone propionate, ketorolac, and phenidone. This model is presented as a practical method for testing anti-inflammatory drugs in the eye.

ISSN:0271-3683    

DOI:10.3109/02713688508999984

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

We examined the role that fibrin deposition and fibrin-associated factors (FAF) play in acute anterior segment inflammatory responses in the rabbit eye. It was demonstrated by immunofluorescence that fibrin represented a major component of the exudative meshwork deposited within the anterior chamber and on leukocyte surfaces therein. Using our in vivo model of endocu lar inflamnation we next demonstrated that fibrin and fibrinogen-derived paptides, but not thrombin, induced inflammatory responses characterized by both leukocyte influx and endothelial cell injury. Fibrin formation within the anterior chamber induced a leukocyte influx consisting primarily of PMN's. Fibrinogen-derived peptidas induced primarily a monocyte influx. This dichotomy suggests that multiple inflammatory mediators are elaborated or released during endocular fibrinogenesis and fibrinolysis.To investigate direct effects of fibrin deposition on the corneal endothelial cells (CEC) an in vitro“corneal cup”organ culture model was next developed. Studies comparing various types of mediators demonstrated that only fibrin-derived preparations directly induced CEC injury.Fibrin deposition may thus play multiple roles in endocular inflammation, including the modulation of leukocyte influx, and the direct mediation of corneal endothelial cell injury.

ISSN:0271-3683    

DOI:10.3109/02713688508999985

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

A model for simulating the endothelial damage caused by surgery is described. The model consists of the introduction of a specially constructed instrument into the anterior chamber and using it for scraping the endothelium of a predetermined, precisely quantifiable area of cornea. The process of healing of the scraped cornea can be followed and measured accurately by biomicroscopy, specular microscopy and histo logical techniques. The model can be used to study the qualitative and quantitative aspects of endothelium healing and the effects of the various endogenous, exogenous and iatrogenic factors on this process. The preliminary data presented shows that the healed endothelium consists of larger and less densly packed cells. The cell density is reduced by 43.3% after one scraping of 57% of the endothelium and by 69.2% after two such operations. Prolonged mild traumatic iritis causes the appearance of endothelial cells with incongruous shapes.

ISSN:0271-3683    

DOI:10.3109/02713688508999986

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

The effect of intraocular surgery on ocular and optic nerve blood flow was determined in rabbits either untreated or pretreated with aspirin. Surgery was either extracapsular lens extraction through a 100d` corneal incision or a sham-operation in which a 45d` corneal incision was performed and the lens left in place. In both cases, the incisions were not sutured and the intraocular pressure remained zero for one hour. A (85Sr) radioactive microsphere technique was used to measure blood flow in the iris, scraped ciliary processes, retina, choroid, and optic nerve. In rabbits not receiving aspirin pretreatment, blood flow was statistically increased in all portions of the eye, except the retina and optic nerve, studied for sham-operated eyes, and in the iris and optic nerve in the lens extraction group. In rabbits pretreated with aspirin, blood flow remained at normal levels. These results are consistent with the hypothesis that prostaglandins released during ocular surgery cause increased ocular tissue blood flow.

ISSN:0271-3683    

DOI:10.3109/02713688508999987

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

Levels of plasminogen activator (PA), plasmi nogen (Plg), and antiplasmin activity (APli) were compared in feline aqueous humor obtained from normal eyes, eyes inflamed by chronic mycobac terial-induced uveitis (CMIU), opposite eyes, and in plasma. Fibrin-agar plate microassays were utilized to visually confirm the extent of differences in in vitro fibrinolysis, per se. Chromogenic peptide (S2251) microassays were utilized to quantify differences.Normal AH showed much more available PA than did plasma. However, when APli activity was first neutralized their levels of total PA were comparable. Available PA activity in both normal and CMIU AH was considerably amplified in the presence of trace amounts of free plasmin. Plasma failed to show this response. AH levels of circulating Plg and APli in normal eyes were far below plasma levels. During CMIU, total PA levels remained approximately normal while levels of Plg and APli were greatly increased. The net effect of these concurrent rises was that antiplasmin activity (APli) prevailed over free plasmin formation; i.e., in vitro fibrinolysis was suppressed. Plasma levels of PA, Plg and APli did not change during CMIU.Changes in the normal PA+Plg/APli balance induced by CMIU suggested a hypothetical model of AH fibrinolysis wherein exclusion of APli from the normal anterior chamber and the high levels attained during CMUI are posited as key determinants of AH fibrinolytic capability.

ISSN:0271-3683    

DOI:10.3109/02713688508999988

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

The levels of the glycolytic enzymes, phospho hexose isomerase, aldolase and LDH and its isozymes, were ascertained in the aqueous of human stillbirths and premature neonate dead (19–24 weeks gestation) and compared with those of older neonates (28–41 weeks) of low survival due mainly to respiratory failure. The fetal aqueous displayed a much greater LDH-P level (mean mil/ml±SEM: 45,600±2550; 72 eyes) in contrast to the near-term infant value (2420±615; 27 eyes) and 8–20 times higher aldolase and phosphohexose isomerase levels. LDH-P of the fetal vitreous was much lower (5820±860 mU/ml; 25 eyes) and for lens employed as a filtered homogenate in saline (1:20), amounted to 52.2±4.2 mU/mg lens (24 eyes). The distribution of LDH isozymes in the fetal vitreous and lens homogenate and the near-term neonate aqueous as determined by polyacrylamide disc electro phoresis, was similar to that of the fetal aqueous, LDH-1 and LDH-5 being least and LDH-3 and LDH-4, the highest. A few small but significant differences were apparent as compared to the fetal aqueous isozymes and included decrements in vitreous LDH-4, lens LDH-3 and neonatal aqueous LDH-3 and increases in vitreous LDH-2 and near-term aqueous LDH-4. The current findings may have application to retinoblastoma for which higher aqueous LDH levels have been reported and employed as a diagnostic adjunct. However, the fetal aqueous LDH values far exceed those encountered in this embryonal-type tumour.

ISSN:0271-3683    

DOI:10.3109/02713688508999989

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

Experimental designs in ophthalmologic research frequently treat both eyes of a subject in the same fashion: e.g., therapy with a specific drug or control. In these two-eye designs, observations from the same subject are often positively correlated. Failure to account for this correlation is a serious error which overstates the precision of studies, resulting in falsely significant results.This paper reviews the statistical methods appropriate for studies where endpoints are quantitative. We present: (1) the use of analysis of variance (t-test when there are 2 treatment conditions) to estimate differences between all experimental treatments, (2) the use of contrasts to estimate differences between specific treatments, and (3) methods for analysis of data from multiple experiments.Because of the ubiquity of incorrect analysis of data from two-eye designs in the ophthalmologic research literature and the serious consequences of this error, we propose a limited statistical review of manuscripts to ascertain if the statistical analysis matched the experimental design.

ISSN:0271-3683    

DOI:10.3109/02713688508999990

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

The expression of MHC Class I and Class II antigens was investigated in the human uvea using monoclonal antibodies in an indirect immuno fluorescence technique. The anterior border layer of the iris, the non-pigmented and pigmen ted epithelium of the ciliary body, the external basement membrane of the ciliary body and the vascular endothelium in the uvea showed a positive staining for Class I antigens. The endothelium lining the bloodvessels in the uvea expressed the highest density of Class I antigens. Class II antigens were found only on single cells spread throughout the entire uvea. These cells did not seem to relate to any anatomical entity. No staining for Class II antigens was detected in the uveal blood vessel endothelium. The expression of HLA-antigens in the uvea may provide insight in the pathogenesis of certain HLA associated uveitis entities.

ISSN:0271-3683    

DOI:10.3109/02713688508999991

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

A steroid antagonist applied to one eye of 18 young pigmented rabbits during a 10-week period caused a statistically significant fall in IOP, but no statistically significant nor clinically relevant change in the rate of aqueous humor turnover. The pressure change is therefore ascribed to an alteration in outflow channels. No changes occurred in a parallel group of 5 animals in which one eye was treated with vehicle and the contralateral eye was untreated. The drug effects became evident after two weeks of application, suggesting that a slow turnover pathway is involved.

ISSN:0271-3683    

DOI:10.3109/02713688508999992

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

S-antigen has been quantitated in bovine and rat retina by electroimmunoassay. The molar ratios S-antigen to rhodopsin in photoreceptor cells were close to 1:1.Immunofluorescence studies show that light induces a shift of S-antigen towards the rod outer segments where it concentrates. Assays indicate that S-antigen becomes largely water insoluble but detergent soluble under these conditions. On basis of previous ultrastructural and present results, this has been interpreted as a light induced binding of S-antigen to the rod outer segment membranes.The data support evidence from literature that S-antigen interacts with (rhod)opsin and we conclude that S-antigen plays a major role in the phototransduction process.

ISSN:0271-3683    

DOI:10.3109/02713688508999993

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor