Effect of a topically applied neutralizing antibody against vascular endothelial growth factor on corneal allograft rejection of rat.

BACKGROUND: Studies in corneal transplant rejection remain important because acute immunologic rejection continues to be the leading cause of human corneal transplant failure. As the permeability of vessels and the neovascularization induce cells infiltration into the graft, we considered the possibility that vascular endothelial growth factor (VEGF), a potent permeability-increasing factor and angiogenesis-mediating factor, could participate in the immune response. METHODS: As the established corneal transplant model for rejection, the corneal transplant between Lewis and Fisher rats has been reported. First, we evaluated VEGF production in the graft by immunohistochemical method in the animal model. Next, we tried to neutralize the effect of VEGF by topical administration of anti-VEGF antibody. We administered anti-VEGF antibody as eye drops for 10 days just after the transplantation of the established animal corneal transplant model. RESULTS: VEGF was strongly produced from the infiltrative cells into the graft. Anti-VEGF antibody significantly suppressed the acute rejection compared with saline or rabbit IgG. CONCLUSIONS: The inhibition of VEGF by topically applied neutralizing antibody is a new potential therapeutic strategy for the treatment of corneal transplantation.

Phencyclidine-induced retrograde amnesia in mice.

The amnesic action of phencyclidine (PCP) was investigated in mice using a passive avoidance- and escape-learning method. PCP (10-30 mg/kg) administered immediately after the training test dose-dependently shortened and prolonged the step-down latency and escape latency, respectively in the retention test. There was a significant inverse relationship between the step-down and escape latencies, indicating that PCP had induced amnesia. The amnesic actions of PCP were retrograde, being observed when mice were given PCP within 10 min but not more than 30 min after the training test. The amnesic effects of PCP on both variables were antagonized significantly by physostigmine and naloxone, whereas cyproheptadine and haloperidol had no effect. None of these drugs by themselves affected passive avoidance- or escape-learning performance. These results suggest that the retrograde amnesic actions of PCP were produced via either the cholinergic or the opioidergic systems or both, but not through the serotonergic and the dopaminergic systems.

Experimental study of small intraocular lenses using an eye model.

Contrast and glare tests were performed on small intraocular lenses (IOLs) using a new eye model, which was based on and about the same size as the Gullstrand eye model. Lenses with a small optic diameter were inserted and retinal images were observed under the operating microscope. Contrast and glare disability tests were done using the MCT-8000 contrast tester and the Miller-Nadler glare tester. No effect on contrast sensitivity attributable to glare was observed, but under severe glare light conditions a faint reflection around the circumference of the optic was found. Questionnaires from patients implanted with small optic IOLs confirmed that this phenomenon was similar to their symptoms.

The antagonistic effects of naloxone on cycloheximide and anisomycin-induced amnesia.

The amnesia induced by cycloheximide (CXM) injected SC and by CXM or anisomycin injected ICV immediately after the training test was antagonized in combination with an opiate antagonist, naloxone (NLX). This antagonism occurred on both the passive avoidance- and escape-learning responses in a dose-dependent manner in mice. NLX alone (0.3-10.0 mg/kg) did not alter the performances of these tasks. Furthermore, the decrease in retention performance on shuttle avoidance in rats induced by CXM was also antagonized by NLX. Treatment with CXM and/or NLX did not affect spontaneous locomotor activity. The interaction of these drugs on the performance of the passive avoidance- and escape-learning and the shuttle avoidance tasks may be related to neurochemical memory processes. These results suggest that an opioid system may participate in the amnesic actions induced by protein synthesis inhibitors in these models.

[The retinal image of three multifocal intraocular lenses through an eye model].

Retinal images produced by two types of multifocal intraocular lenses (IOLs) were studied using an eye model. One of them was a refractive IOL with five zones, and the other was a diffractive lens. The IOLs were inserted into an eye model with a pupil diameter of 3 mm. The retinal plane of the eye model was observed microscopically. When the section of the IOL used for far vision was in focus, the retinal image of the refractive IOL was almost the same as that of the monofocal IOL, which was better than that of the diffractive IOL. When the near vision section of the IOL was in focus, the retinal image of the diffractive IOL had almost the same quality as the far section. The light rings produced when the multifocal IOLs were illuminated by a glare source were also examined. They showed that the diffractive IOL was stronger than the refractive IOL, but the monofocal was the smallest of the three.

[Accuracy of intraocular power calculation formulas].

PURPOSE: We examined the accuracy of intraocular lens power calculation formulas, with special emphasis on the prediction of refraction in different axial lengths. MATERIAL AND METHODS: 786 cases were subdivided into four groups based on the axial length (short axial length < 22.0 mm, normal axial length = 22-24.4 mm, mid-range axial length = 24.5-26.9 mm and long axial length > 27 mm). Seven different formulas (Holladay, SRK, SRK II, SRK/T, S-SRK, M-SRK, L-SRK) were tested for their accuracy in predicting post-operative refraction. RESULT: The best results were obtained using the S-SRK formula in the short axial length group (n = 114), The SRK and Holladay formulas in the normal axial length group (n = 278). The Holladay and SRK/T formulas in the mid-range axial length group (n = 135), and the SRK/T and L-SRK in the long axial length group (n = 259). CONCLUSION: Our results emphasize the importance of using an intraocular lens formula specific for each range of axial length when calculating the predicted refraction.

[Vascular endothelial growth factor levels in the aqueous and serum in diabetic retinopathy with or without neovascular glaucoma].

We determined the levels of vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) in the aqueous and serum in non-insulin dependent diabetic patients with proliferative retinopathy (n = 12) and neovascular glaucoma (n = 11). The aqueous levels of PEGF/VPF were significantly higher in both groups than in 10 diabetics without such complications. The levels were very high in patients with neovascular glaucoma, suggesting that VEGF/VPF is involved in the pathogenesis and progression of diabetic neovascular glaucoma. The serum levels were not significantly related to the presence or the stage of retinopathy. The findings suggest the possibility of treatment of neovascular glaucoma using anti- VRGF/VFP preparations.

[Relationship between immediate hypersensitive reactions by buckwheat ingestion and specific IgE for rice in subject with positive IgE-RAST for buckwheat].

IgE-mediated mechanisms are important in immediate hypersensitive reactions (IHR) to buckwheat. However, a part of subjects with high IgE for buckwheat show no IHR to buckwheat ingestion. Inspite of cross-allergenicity between buckwheat and rice, rice ingestion rarely induces IHR even in subjects with high IgE for rice unlike buckwheat-induced IHR. We speculated that there were some relationships between the presence of IHR to buckwheat and recognition of cross-allergenic determinants on buckwheat components with rice components. We examined IgE-RAST for rice in 58 subjects with positive IgE-RAST for buckwheat. IgE-RAST for Dermatophagoides pteronyssinus (Dp), egg white and cow's milk as unrelated antigens with rice were also assessed for a comparison. Subjects (n = 33) without IHR to buckwheat showed higher IgE-RAST values for rice than those (n = 25) with IHR, whereas there were no differences in IgE-RAST values for Dp, egg white and cow's milk between two groups with and without IHR. IgE-RAST values for buckwheat showed significant close correlations to those for rice in subjects without IHR to buckwheat but not in those with IHR. There were no significant correlations between IgE-RAST values for buckwheat and for Dp, egg white or cow's milk in both groups with and without IHR. These results suggested that the IgE from subjects without IHR to buckwheat recognized cross-allergenic determinants with rice on the buckwheat components.

[Influence of tonsillar hypertrophy to school-life of children].

The authors examined degree of facial tonsillar hypertrophy for 7190 pupils of elementary schools in nine different areas in Japan. The frequency of the third degree of tonsillar hypertrophy, based on Mackenzie's criteria, decreased gradually from 6.9% of the first-year pupils to 2.9% of the sixth-year pupils with a mean of 4.8%. We also studied the relation between the degree of tonsillar hypertrophy of each pupil and the reply to the questionnaire from his or her teacher regarding various aspects of his or her school-life. The third degree of tonsillar hypertrophy of each pupil and the reply to the questionnaire from his or her teacher regarding various aspects of his or her school-life. The third degree of tonsillar hypertrophy seemed to affect school-life of pupils. For example, the frequency of pupils whose speech can be clearly recognized, was less in pupils with the third degree of tonsillar hypertrophy than in pupils without any tonsillar hypertrophy. Pupils of higher grades with the third degree of tonsillar hypertrophy were classified into two groups. One was the pupils whose school-life was not altered by tonsillar hypertrophy. The other was the pupils who were often absent from school due to chronic or acute tonsillar inflammation.

[Influence of tonsillar hypertrophy to physical growth and diseases of the nose and ear in school-age children].

The authors investigated the influence of facial tonsillar hypertrophy to physical growth, and diseases of the nose and the ear for 7190 pupils of elementary schools in nine different areas in Japan. Tonsillar hypertrophy seemed to prevent physical growth of pupils of lower grades. In pupils without tonsillar hypertrophy, the number of pupils suffering from rhinitis gradually decreased from 16.9% in the first grade to 8% in the sixth degree. On the other hand, the number of pupils suffering from rhinitis remained to be large, ranging between 20.5% and 29.7% in the group of tonsillar hypertrophy. The number of pupils with hearing loss were much more in the group of tonsillar hypertrophy. Since an only available diagnostic mean of ear disease was an otoscopic examination, a significant number of pupils with serous otitis media may be labeled as hearing loss. For this reason, tonsillar hypertrophy possibly affected the number of pupils with hearing loss. There were no apparent relations between tonsillar hypertrophy and allergic rhinitis, chronic paranasal sinusitis and chronic otitis media.

The endo-mirror, a new instrument for ophthalmic surgery requiring visualization of the ciliary sulcus.

Safely suturing a posterior chamber intraocular lens (PC-IOL) to the ciliary sulcus requires a means of visualizing the ciliary sulcus, since it cannot be viewed directly with the operating microscope. We, therefore, created several trial instruments consisting of a mirror with a built-in light source, which we call an endo-mirror, designed for observing the area behind the iris. Using these instruments, we were able satisfactorily to view the ciliary sulcus and suture a PC-IOL to it, first in a number of animal eyes, and then, using an endo-mirror incorporating the best features of the trial versions, in actual clinical cases.