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Manabu Kase

Publications and source records attributed to Manabu Kase.

7 recordsLinked to original sources
PubMed2005

Retinal neovascularization during treatment with IGF-1 for insulin resistance syndrome.

BACKGROUND: Leprechaunism is a rare congenital syndrome and the most severe form of insulin resistance syndrome, with mutations in the insulin receptor gene. Recombinant human insulin-like growth factor-1 (rhIGF-1) is currently applicable to the treatment for insulin resistance syndrome by its insulin-like effect. Although IGF-1 is thought to promote tissue proliferation and neovascularization, it is uncertain how it acts on the development of diabetic retinopathy. METHODS: Interventional case report. RESULTS: A 12-year-old girl with leprechaunism has been treated with IGF-1 since she was 6 months old. She presented with neovascular glaucoma in the left eye, but with no serious changes in the right fundus except for tortuosity and dilatation of retinal veins. Thereafter, retinal neovascularization in the right eye developed in 6 months to form a loop-shaped vascular network in the vitreous cavity despite panretinal photocoagulation. CONCLUSIONS: Characteristics of retinal neovascularization and clinical course suggest that IGF-1 treatment was closely associated with the development of diabetic retinopathy in this case.

Blindness↗
PubMed2002

Advanced glycation end products induce angiogenesis in vivo.

Advanced glycation end products (AGEs) have been thought to participate in diabetic microangiopathy. However, the effects of AGEs on angiogenesis have so far been mainly examined either in vitro or by using cultured cells. In the present study, we have analyzed whether AGEs induce angiogenesis in vivo by using the chorioallantoic membrane (CAM) assay. The CAM assay was carried out in embryonated hen eggs to determine the effects of AGEs. Following generation of AGEs based on bovine serum albumin (BSA), either AGE-BSA or nonglycated BSA was administered to the CAM and their effects on angiogenesis were assessed, together with an inhibitory effect of an anti-AGE antibody against AGE-BSA-induced angiogenesis. The histological features of AGE-induced vascular lumens were examined by immunohistochemical analysis for Factor VIII and smooth muscle alpha-actin. AGE-BSA induced angiogenesis in CAM in a dose- and time-dependent manner. AGE-induced angiogenesis on CAM was neutralized by the anti-AGE antibody. Immunohistochemical analysis demonstrated that AGE-induced vascular lumens were devoid of pericytes. Our data demonstrated that AGEs are an angiogenetic factor and that our system of AGE-induced abnormal vessels in CAMs is useful in further investigations of the mechanism of diabetic retinal angiogenesis and can also be used to provide a therapeutic model for diabetic angiopathy.

Animals↗
PubMed2002

Ocular torsion produced by unilateral chemical inactivation of the cerebellar flocculus in alert cats.

PURPOSE: Vertical eye movements are executed by the vertical recti and oblique muscle pairs. Since each of these pairs rotates the eye in both vertical and torsional directions, torsional components must be controlled to execute appropriate, purely vertical eye movements. To test whether the cerebellar flocculus is involved in the control of torsional eye position, we examined the effects of unilateral chemical inactivation of the flocculus on ocular torsion in alert cats. METHODS: Pitch-responding floccular regions were first identified, then the GABA agonist muscimol was injected unilaterally into the identified regions. Ocular torsion was examined photographically. RESULTS: Unilateral muscimol infusion into pitch-responding areas in the rostral and middle parts of the flocculus resulted in significant intorsion of the eye ipsilateral to the infusion. Gaze-holding was also impaired following downward saccades induced by visual stimuli. Although the contralateral eye showed a tendency towards extorsion, the effects were not significant. Muscimol infusion into the caudal flocculus did not induce consistent effects on ocular torsion. CONCLUSION: The cerebellar flocculus plays a key role in the maintenance of torsional eye position.

Animals↗
PubMedDate not supplied

Retinal vasculitis due to secondary syphilis.

BACKGROUND: Retinal vasculitis is one of the manifestations of ocular syphilis. CASE: A 29-year-old man was referred to our hospital with the complaint of sudden visual loss in the left eye lasting more than three weeks. OBSERVATIONS: Ophthalmoscopic examination showed retinal hemorrhages, edema, and sheathing of large retinal arteries and veins. Fluorescein angiography revealed extensive occlusion of the affected retinal arteries, veins, and capillaries. Little evidence of uveitis or vitritis was observed. The fluorescent treponemal antibody-absorption test was positive, and the Treponema pallidum hemagglutination titer was 1:10,240. The treatment with penicillin was effective, leading to resolution of the retinal hemorrhages and edema, although occlusion of the retinal vessels persisted. CONCLUSIONS: Vascular occlusion occurred simultaneously in large retinal arteries, arterioles, and capillaries as well as in segments of retinal veins, resulting in irreversible changes in the vascular walls.

Adult↗
PubMedDate not supplied

Leaky neural integration observed in square-wave jerks.

PURPOSE: To clarify the neuronal mechanism for the square-wave jerks (SWJs). METHODS: A 66-year-old man presented with oscillatory eye movements. He showed horizontal nystagmus in rightward gaze and SWJs during fixation at straight ahead. We recorded his eye movements with search coil methods and quantitatively analyzed them. RESULTS: Visually guided rightward saccades were followed by exponential drifts with average time constants of 0.3-1.0 second, indicating a leaky rightward velocity-to-position integrator. Amplitude of SWJs ranged from 0.5 to 2.5 degrees and average intersaccadic interval was 0.2 seconds. In addition, exponential drifts similar to those observed after visually guided saccades were observed in the SWJs. Rightward fast eye movements of SWJs were followed by exponential drifts lasting for 0.2 seconds with average time constant (+/-SD) of 0.7+/-0.3 seconds. CONCLUSIONS: Position signals after visually guided saccades and SWJs were outputs of the identical velocity-to-position integrator. SWJs are generated by the neural circuits involving a pulse generator and a velocity-to-position integrator.

Aged↗
PubMedDate not supplied

Reversible Horner's syndrome and dysthyroid ocular myopathy associated with Hashimoto's disease.

BACKGROUND: Although it has been frequently stated that thyroid disease induces Horner's syndrome, there have been few reports describing the anatomical relation of goiter to the cervical preganglionic sympathetic nerve fibers in acquired Horner's syndrome, which is identified by the eye-drop test for adrenergic sensitivity. CASE: A 40-year-old woman with Hashimoto's disease presented with vertical diplopia, and blepharoptosis and miosis on the left side. OBSERVATIONS: Computed tomography scan showed hypertrophy of the right inferior rectus muscle, which resulted from a dysthyroid process, causing the limitation of upward movement of the right eye. The eye-drop test for adrenergic sensitivity revealed that only the left pupil dilated significantly after administration of 5% tyramine, and the Mueller's muscle on the left side did not respond. These results suggest that Horner's syndrome was due to a preganglionic sympathetic lesion. Magnetic resonance imaging (MRI) of the neck showed chronic inflammatory lesions in both lobes of the thyroid gland identified by a high-intensity signal. CONCLUSION: The reconstruction technique of MRI demonstrated that the swollen left lobe of the thyroid gland was compressing the pathway of the cervical preganglionic sympathetic nerve fibers.

Adult↗