Masanori Inoue

Tear function and ocular surface changes in noninsulin-dependent diabetes mellitus

PURPOSE To describe the ocular surface disorder in patients with diabetes. DESIGN A prospective, case-controlled study. PARTICIPANTS Eighty-eight eyes of 50 noninsulin-dependent diabetes mellitus patients seen at the Department of Ophthalmology, Kobe University School of Medicine, from September 1998 through February 1999, and 40 eyes of 20 healthy control individuals were studied. INTERVENTION All subjects underwent routine ophthalmic examinations, corneal sensitivity measurements, Schirmer test, tear film break-up time (BUT) analysis, and conjunctival impression cytologic analysis. MAIN OUTCOME MEASURES Patients and control subjects were compared for corneal sensitivity, tear function parameters, goblet cell density, and squamous metaplasia grade. The relation of diabetic peripheral neuropathy, metabolic control, duration of disease, and status of retinopathy to the ocular surface disorder was also noted. RESULTS The mean corneal sensitivity was significantly lower in diabetic patients, diabetic patients with peripheral neuropathy, and poorly controlled diabetes compared with control subjects (P < 0.001). The BUT and Schirmer test values were also significantly lower in the diabetic group, in patients with peripheral neuropathy and poor metabolic control. Impression cytologic analysis showed goblet cell loss and conjunctival squamous metaplasia, both of which again related to peripheral neuropathy, poor diabetic control, and decreased corneal sensitivity. The examined parameters did not relate to duration of disease or status of diabetic retinopathy. CONCLUSIONS The ocular surface disease in diabetes is characterized by a disorder of tear quantity and quality, squamous metaplasia, and goblet cell loss, all of which seem to evolve in close proximity to the status of metabolic control and peripheral neuropathy.

A proenzyme of cyclic nucleotide-independent protein kinase and its activation by calcium-dependent neutral protease from rat liver.

Summary A proenzyme of protein kinase was found in rat liver soluble fraction. Upon limited proteolysis with Ca 2+ -dependent neutral protease or trypsin, the proenzyme was converted to an active protein kinase which was able to phosphorylate calf thymus histone. The proenzyme was inert in this capacity but appeared to show protamine kinase activity. The protein kinase was independent of cyclic nucleotides. The proenzyme showed an approximate molecular weight of 7.7 × 10 4 . The protease required Ca 2+ for its activity with an optimum concentration of 2 to 3 mM . It showed a pH optimum of 7.5 to 8.5 and a molecular weight of about 9.3 × 10 4 as estimated by sucrose density gradient analysis. The method of purification of the proenzyme and protease from rat liver is described.

Modifying factors related to asymmetric diabetic retinopathy

Purpose To identify the modifying factors related to the development of proliferative diabetic retinopathy (PDR).Methods Thirty-eight eyes of 19 non-insulin-dependent diabetes mellitus (NIDDM) patients with maintained asymmetric PDR were retrospectively reviewed.Results Five patients with ipsilateral carotid stenoses &geq;90% had PDR. Four patients with high myopia over 6 dioptres and 4 patients with optic atrophy and at least a quadrant defect in the visual field had non-proliferative diabetic retinopathy. Of 6 patients with unilateral asteroid hyalosis, 5 had no posterior vitreous detachment (PVD) and PDR.Conclusion Two factors reached statistical significance as factors modifying PDR: carotid occlusive disease and PVD. Optic atrophy and high myopia showed trends of being a protective influence.

Cox-2 expression in retinoblastoma

PURPOSE Cox-2, a prostaglandin synthase, is overexpressed in colorectal cancers and is involved in angiogenesis as well as in tumorigenesis. In this study, we investigate the expression of Cox-2 in retinoblastoma. METHODS Twenty-nine formalin-fixed retinoblastoma specimens were examined by the labeled-streptavidin-biotin method using anti-Cox-2 antibody. RESULTS Cox-2 positive immunoreactions were observed in 28 (96%) of 29 retinoblastomas specimens. CONCLUSION This preliminary study suggests the overexpression of Cox-2 in both differentiated and undifferentiated retinoblastoma and its possible role in tumorigenesis.

Retinoblastoma in a 26-year-old Adult

Retinoblastoma in a 26-year-old woman is reported clinicopathologically, and the difficulties in this clinical diagnosis are presented. Clinical and morphologic findings of this case suggest that rare embryonal retinal cells can persist and be subject to late malignant transformation.

Effect of aminoguanidine on optic nerve involvement in experimental diabetic rats

The effect of aminoguanidine (AG) on structural abnormalities in optic nerve fibers was evaluated in streptozotocin-induced diabetic rats. Morphometry of myelinated optic nerve fibers showed a partial amelioration on the reduction of the axon size but complete preservation of myelin size with low dose (25 mg kg-1 body weight) AG treatment. High dose (100 mg kg-1 body weight) AG completely prevented myelinated nerve fiber atrophy. These findings indicated that nonenzymatic glycation contributes to the development of optic nerve changes in diabetic rats.

Management of Eyelid Sebaceous Carcinomas

We retrospectively studied 14 patients confirmed histopathologically to have eyelid sebaceous carcinoma during 1986-1994. We removed all tumors totally with frozen section controls and performed reconstruction either by primary apposition or transposition flaps. We observed recurrence in 5 patients (35.7%) in whom a surgical margin of either 1 or 3 mm was taken but none in those with a 5-mm surgical margin. At least 5 mm of normal tissue around the tumor should be removed considering the metastatic potential of these tumors.

Laser flare intensity in diabetics: correlation with retinopathy and aqueous protein concentration.

The laser flare intensity in diabetics, measured with the scattering of a light beam, was evaluated and compared with actual aqueous protein concentration obtained during surgery. Measurement of the laser flare intensity in 120 diabetics and 108 normal subjects was performed with the laser flare cell meter (FC1000 Kowa, Tokyo). Aqueous protein concentration in 26 diabetics and six controls who underwent intraocular surgery was measured by the method of Bradford. No significant difference in the laser flare intensity was found between normal subjects and diabetics without retinopathy. A significant increase in the laser flare intensity was observed after six decades in diabetics with background retinopathy and all with proliferative retinopathy. The laser flare intensity correlated with the duration of diabetes mellitus. There was a significant linear relation between the laser flare intensity and actual aqueous protein concentration. The linear regression formula was X = Y1.39 x 1.02 (X = protein concentration, mg/dl; Y = flare intensity, photon counts/ms). The precise value of the laser flare intensity provides a new indicator to evaluate the diabetic change in the function of the ocular barrier.

Long-Term Visual Outcome in Proliferative Diabetic Retinopathy Patients After Panretinal Photocoagulation☆

BACKGROUND There is the need for a long-term study on the visual outcome of panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR) patients. CASES We retrospectively reviewed the clinical course and visual results in 66 eyes of 59 patients with PDR who were followed-up for at least 10 years after argon or krypton laser PRP. OBSERVATIONS Thirty-nine eyes had stage B-II, whereas 8 eyes had stage B-III retinopathy. Stage B-IV and B-V retinopathy were seen in 15 and 4 eyes, respectively. Although active stages of diabetic retinopathy were encountered after 5 years, complete regression could be successfully attained after 10 years. Long-term visual prospects were promising for eyes with stage B-II DR; 28.2% still enjoyed 20/40 or better visual acuity by 5 years. Most cases had maintained the same visual acuity at 10 years. Eyes with stage B-III DR did not attain 20/40 vision by 10 years. Panretinal photocoagulation in cases with neovascularization of the optic nerve head was seen to be beneficial but limited, suggesting that such cases might benefit from maximal initial and supplemental PRP followed by vitrectomy and intraoperative endophotocoagulation when necessary. Although 20% of the eyes with stage B-IV and 25% of the eyes with stage B-V DR had 20/40 or better visual acuity, analyses of the visual change revealed that about half the eyes with stage B-IV and all eyes with stage B-V DR experienced a visual loss of two lines or more. CONCLUSIONS Progression of lens opacities, chronic macular edema, vitreous hemorrhage, macular traction, and neovascular glaucoma were the main causes of visual loss in this series. Panretinal photocoagulation for PDR provides good anatomical and visual outcome for 10 years or longer.

Disruption of the Blood-Aqueous Barrier following Retinal Laser Photocoagulation and Cryopexy in Pigmented Rabbits

Disruption of the blood-aqueous barrier (BAB) induced by retinal photocoagulation and cryopexy in pigmented rabbits was evaluated by laser flare photometry. A significant increase in flare values after retinal photocoagulation was measured from the 1st postoperative day, with values returning to baseline levels by day 7. Cryopexy induced consistently high flare values for 14 days. Intravitreal injection of interleukin (IL) 1, IL-6 and prostaglandin (PG) E2 induced a significant increase in flare values. Following these treatments, introduction of a PG synthetase inhibitor can partially ameliorate BAB disruption. IL-1, IL-6 and PGE2 may be involved in BAB disruption following retinal photocoagulation and cryopexy.