Investigative ophthalmology最新文献

The eye disease caused by SMCA may be best characterized as an endophthalmitis, with early retinitis followed by subsequent posterior uveitis. Pathologic features of lens included: proliferation and abnormal posterior extension of lens epithelium, increased accumulation of lens capsule material, and production of aberrant lens substance. Cataractous change appears to be secondary to intraocular inflammation. In addition to the above pattern, in roughly 20 per cent of all cases, 3 weeks after inoculation, lens capsule is destroyed giving rise to a foreign body granulomatous reaction.

Conjunctival and skin biopsies from two new patients with fucosidosis were studied by electron microscopy. In both tissues, the connective tissue cells and the capillary endothelial cells were filled with single membrane limited inclusions of two types: (1) Clear inclusions containing a fibrillogranular reticulum. (2) Dark inclusions with a dense granular material. Specific stainings in ultrastructure suggest that these inclusions contain oligosaccharide chains. The ultrastructural aspect is characteristic for fucosidosis. Enzyme studies on tears realized an easy and secure technique for the diagnosis of the disease.

A grating pattern presented to one eye of an individual capable of alternating suppression induces a visual aftereffect (contrast threshold elevation), even when the pattern is phenomenally suppressed from vision. This finding indicates that strabismic suppression occurs within the visual system after the site of the aftereffect, and points out a similarity between strabismic suppression and binocular rivalry suppression.

A morphological study of Coats' disease was performed with light and electron microscopy. The choroid was intact throughout. The pigment epithelial cells showed proliferative changes, being thickened in two or three rows. The transitional form of ghost cell was observed in contact with the pigment epithelial layer, then migrated toward the subretinal space, and finally invaded the detached retina. It was concluded that the origin of ghost cell in Coats' disease was the pigment epithelium.

The acridine orange is an excellent vital stain for the "in vivo" study of the lysosomal dynamics in cultured keratocytes. In normal keratocytes the lysosomes are mostly grouped around one or both nucleus poles. In keratocytes from macular dystrophy of the cornea there is a hypertrophy of the lysosomal system, which in vain tends to compensate for the consequences of the enzymatic deficiency.

The sulfated material which locates in the basal membrane of ciliary body epithelium when immature rat eyes are incubated with Na235SO4 was studied. On the basis of its chromatographic behavior compared with standard preparations, we conclude that the material consists of sulfatides.

A high incidence of keratoconjunctivitis was observed in a closed colony of inbred Lewis/Wistar rats. Clinical signs including blinking, ocular discharge, circumcorneal flush, corneal opacity, ulceration, pannus, hypopyon, and hyphema were observed at about three weeks of age. Acute disease subsided by six weeks of age, but some lesions progressed to low-grade chronic keratitis. Six per cent of affected rats developed megaloglobus, which usually appeared by three weeks of age. Lesions included focal or diffuse interstitial keratitis, corneal ulceration, anterior synechia, and inflammatory exudate in the anterior chamber. A high incidence of lenticular and retinal degeneration was associated with megaloglobus. Most affected rats also had harderian dacryoadenitis. Sialodacryoadenitis virus (SDA) was recovered from nasal washes, but not from affected eyes. Serological evidence indicated that SDA virus infection was widespread in the colony.

The effect on contralateral eyes after injuries to one eye has been called the consensual reaction and has been postulated to be either the consequence of a neural reflex or one achieved by circulating substances. Trigeminal stimulation always causes ipsilateral miosis, ocular hyperemia, intraocular hypertension, and a disruption of the blood-aqueous barrier. Disruption of the blood-aqueous barrier in the contralateral eye after stimulation of the trigeminal nerve always occurs and depends on intact sensory innervation to that globe in rabbits. The disruption is not prevneted by pretreatment of the animals with indomethacin. The phenomenon of disruption of the barrier is sometimes accompanied by an elevation of intraocular pressure in the contralateral eye but not by the other irritative responses. Thus, unilateral stimulation of a sensory nerve, the trigeminal, in the rabbit, can produce ipsilateral contralateral disruption of the blood-aqueous barrier.

The properties of monoamine oxidase activity in homogenates of the iris-ciliary body, superior cervical ganglion, and pineal gland of albino rabbits have been studied. Inhibition curves using specific inhibitors support the concept of A and B enzyme forms, with the following ratios of A/B activity: iris-ciliary body, 40/60; superior cervical ganglion, 90/10; pineal gland, 13/87. Experiments on enzymes from animals with superior cervical ganglionectomy indicate that both A and B forms in the iris-ciliary body have a predominantly extraneuronal location. No significant differences in activity were observed between iris-ciliary body preparations from normal and denervated animals with substrates specific for A or B forms, or with substrates deaminated by both A and B forms. With tryptamine as substrate the iris enzyme can be inhibited by a variety of common monoamine oxidase inhibitors. Topical application of the inhibitor pargyline lowers intraocular pressure in the normal rabbit eye but not in the sympathetically denervated eye. This observation and in vitro data suggest that the mechanism of action of pargyline is through the adrenergic system and not dependent upon intrinsic activity.