Immunohistochemical distribution of delta opioid receptors in the rat central nervous system: evidence for somatodendritic labeling and antigen-specific cellular compartmentalization.

Many studies have reported on the distribution of delta opioid receptors (delta OR) in the mammalian central nervous system (CNS) by using a variety of techniques. However, no general consensus has emerged with regards to the localization of this receptor due to inconsistencies in the immunohistochemical literature. In the present study, we analyzed the cellular and subcellular distribution of immunoreactive delta OR in the rat CNS using two different antibodies (directed against a sequence in the C-terminus or N-terminus of the rat delta OR). By using Western blotting, these two antibodies recognized similar forms of the delta OR in COS-7 cells transfected with this receptor, but distinct forms in membranes from the rat spinal cord. By using light microscopic immunohistochemistry, both antibodies recognized identical populations of nerve cell bodies throughout the CNS; the distribution of these cell bodies conformed to that of delta OR mRNA-expressing cells detected by in situ hybridization. However, whereas the C-terminus-directed antibody recognized predominantly perikarya and proximal dendrites, the N-terminus-directed antibody also labeled extensively dendritic and terminal arbors. Furthermore, by using electron microscopy, the two antibodies were found not only to label differentially somatodendritic versus axonal compartments, but also plasma membrane versus cytoplasmic ones, suggesting that distinct immunological forms of the receptor are being targeted preferentially to different cellular and subcellular domains.

Investigation of the role of prolactin in the development and function of the lacrimal and harderian glands using genetically modified mice.

PURPOSE: To determine whether prolactin receptor is essential for normal development and function of the lacrimal gland and whether hyperprolactinemia can alter lacrimal development. METHODS: Lacrimal gland morphology and function were examined in two genetic mouse models of prolactin action: a prolactin receptor knockout model that is devoid of prolactin action and a transgenic model of hyperprolactinemia. RESULTS: Image analysis of lacrimal and Harderian gland sections was used to quantify glandular morphology. In females, lacrimal acinar area decreased by 30% and acinar cell density increased by 25% over control subjects in prolactin transgenic animals, but prolactin receptor knockout mice showed no changes. In males, transgenic animals showed no changes, but prolactin receptor knockout mice showed a 5% reduction in acinar area and an 11% increase in acinar cell density, which was lost after castration. The morphology of the Harderian glands underwent parallel changes but to a lesser degree. A complete loss of porphyrin accretions was seen in the Harderian glands of male and female knockout animals. No differences in tear protein levels were seen in knockout animals by two-dimensional gels. Enzyme-linked immunosorbent assay (ELISA) and Western blot analysis showed that the level of secretory component and IgA in knockout mouse tears remained unchanged. There was no change in the predisposition of the 129 mouse strain to conjunctivitis in the knockout animals. CONCLUSIONS: Prolactin plays a small role in establishing the sexual dimorphism of male lacrimal glands. In females, hyperprolactinemia causes a hyperfemale morphology, suggesting a role in dry eye syndromes. Prolactin is required for porphyrin secretion by the Harderian gland but plays no essential role in the secretory immune function of the lacrimal gland.

Mucosal defense of the outer eye.

A combination of mechanical, anatomical, immunological, and microbiological factors prevent infection of the outer eye. Mechanical and anatomical factors include the intact epithelium of the conjunctiva and cornea and the constant blinking action of the eyelids. Tear components that play a role in eye defense include lysozyme, immunoglobulins, lactoferrin, and betalysin. The normal bacterial flora of the conjunctiva may also have an inhibitory effect on the survival of more pathogenic species. The eye is linked to the common mucosal immune system, thus gaining the benefits of a system of microbial defense which is primed in the gastrointestinal tract, where a continuing large antigen load is capable of stimulating ongoing immune protection. The relative roles of the various factors contributing to prevention of eye infection remain to be fully defined.

Suppression of viral replication by guanidine: a comparison of human adenoviruses and enteroviruses.

A comparison was made between the relative sensitivities of laboratory strain human adenoviruses and enteroviruses, and recently isolated human enteroviruses, to the presence of guanidine hydrochloride in cell culture media. The concentration of guanidine hydrochloride used was 100 micrograms per ml. Representatives of all six human Adenovirus subgenera were unaffected in their replication at this concentration of guanidine. The different human Enterovirus types examined varied in their sensitivity, with suppression ranging from less than 1 to 3 log10 units for laboratory strains, and from 2 to 7 log10 units for recently isolated viruses. The findings suggest a novel role for antiviral drugs; serving as an adjunct in facilitating selective isolation of specific virus groups which may be present as part of mixed viral populations.

Transient corneal changes associated with the use of gold foil electrodes.

The corneas of 50 normal subjects were examined before and after electroretinography performed with gold foil electrodes. Examination included slit-lamp biomicroscopy and staining with sodium fluorescein. All corneas were normal on examination prior to electroretinography. Three types of transient corneal changes were observed--punctate epithelial keratitis, corneal erosions, and stromal thinning. Each cornea was assigned a numerical damage score based on a simple scoring system. Thirty one subjects (62%) had some degree of corneal change, and in three cases (6%) follow-up was required. Multiple regression analysis was performed to discover any risk factors. Both age of the subject and the use of local anaesthetic were strongly associated with corneal changes.

Suppurative keratitis: a late complication of radial keratotomy.

A 21-year-old man who had radial keratotomy performed two years previously presented with a painful, red right eye. Suppurative keratitis was found in one of the eight radial incisions and Staphylococcus epidermidis was isolated by culture. Lack of stromal healing of the infected incision and the presence of epithelial cysts in four other incisions in the same eye suggest that the cause of the corneal infection was loss of the epithelial barrier function because of epithelial breakdown.

Microbiological and histopathological confirmation of acanthamebic keratitis.

A healthy 42 yr-old woman presented with a left keratitis which she had had for 3 months. No organisms could be grown by culture of corneal scrapings for bacteria and fungi, and the condition failed to respond to topical therapy. Amebic keratitis was diagnosed following corneal biopsy and cultures which grew Acanthamoeba of a species similar to, but not identical with, Acanthamoeba polyphaga. Medical treatment was continued for 6 mth. During this time the corneal infiltrate became less prominent but visual acuity remained impaired by both corneal opacity and cataract.

Late development of localized band keratopathy in relation to a Molteno tube.

We report a case in which, 6.5 years postoperatively, localized band keratopathy developed in relation to a Molteno tube. At no stage had direct contact been noted between the tip of the tube and the corneal endothelium. The mechanisms of development of corneal opacities in relation to anterior chamber drainage tubes are discussed and the implications for the placement of such tubes are examined.

Diagnosis and management of chronic blepharokeratoconjunctivitis in children.

PURPOSE: To describe the history, symptoms, and clinical signs and discuss the treatment of blepharokeratoconjunctivitis. METHODS: Eight children (five girls and three boys), ranging in age from 3.5-13 years, were clinically diagnosed with blepharokeratoconjunctivitis. Microbiology studies were performed in four of the eight children. Treatment consisted of lid hygiene, oral erythromycin suspension, and preservative-free steroids. Duration of therapy was directed by clinical improvement. RESULTS: Average age at onset was 3.2 years (range: 0.5-8 years). Lid disease, conjunctival redness, and inferior superficial corneal vascularization were consistent features (100%). Other signs were punctate corneal epithelial staining, inferior subepithelial vascularization and infiltrate, conjunctival phlyctenules, corneal phlyctenules, and circumferential pannus. Microbiology testing demonstrated coagulase-negative staphylococcus and Propionibacterium acnes. Average follow-up was 8.3 months (range: 2-23 months). All patients had relief of symptoms within 2-3 weeks. Clinical signs took more time to regress but all had progressive improvement of the ocular surface by 2 months. Blepharokeratoconjunctivitis reactivated in all patients during follow-up, and repeat therapy was administered. CONCLUSION: Blepharokeratoconjunctivitis in childhood is a chronic inflammatory process that can have different presentations. It can be successfully treated with oral erythromycin and topical steroids.

Traumatic hyphaema. Outcome and management.

The files of 206 patients who had sustained a hyphaema as a result of a contusion injury and had been admitted to Sydney Eye Hospital between January 1979 and December 1981 were reviewed. Most hyphaemas were small (189 or 91.7 per cent), occupying less than one-third of the volume of the anterior chamber. Fifteen patients had a secondary haemorrhage while in hospital and nine of these had a small hyphaema.

Vision-threatening thyroid orbital disease--the clinical features.

Thyroid orbital disease may threaten sight when acute proptosis causes corneal exposure or when enlarged extraocular muscles cause compressive optic neuropathy. The early clinical signs of thyroid optic neuropathy include loss of colour perception and visual field defects. The onset of thyroid optic neuropathy is difficult to predict and these clinical tests should be included in the routine examination of patients with thyroid orbital disease.

Spontaneous onset of ciliary block glaucoma in acute hydrops in Down's syndrome.

A flat anterior chamber and raised intraocular pressure are unusual complications of acute hydrops. We report a case in which a patient with Down's Syndrome developed a flat anterior chamber, together with raised intraocular pressure, several weeks after the onset of acute hydrops.

Uveitis: a strategy for diagnosis.

Uveitis may be the first presentation of a wide variety of underlying ocular and systemic diseases. It is important for the ophthalmologist to make a specific diagnosis in order to instigate specific therapy and give an accurate prognosis. The ability to recognise the clinical patterns of uveitis and to initiate appropriate investigations should form the basis of the ophthalmologist's management of the condition. To this end, we have considered uveitis under four major patterns of presentation--anterior uveitis, intermediate uveitis, posterior uveitis, and panuveitis--with subclasses within each of these four groups. We have outlined both the investigations which facilitate diagnosis of the possible underlying causes of inflammation and the interpretation of the results of such investigations.

Long-term comparison of Novafil and nylon in corneoscleral sections.

To compare the long-term degradation of Novafil (polybutester, American Cyanamid Company) and nylon suture material, we examined corneoscleral sections of nine rabbits 23 months after the placement of sutures. Only two nylon sutures remained, one in each wound of two rabbits; all the Novafil sutures were still present. However, examination of the Novafil sutures with scanning electron microscopy revealed signs of disintegration.

Delayed onset sympathetic ophthalmia.

Three cases of sympathetic ophthalmia that occurred up to 62 years after an ocular injury are reported. Sympathetic ophthalmia occurred spontaneously in the first case, 62 years after a shot-gun pellet had penetrated one eye. In the other two cases, further surgery had been performed on previously-injured eyes. This was followed by a bilateral granulomatous panuveitis that developed within a week in one case and after seven years in the other case. The risk of elective surgery in eyes that are already at risk of sympathetic ophthalmia and the practical aspects of patient counselling are discussed.

Microbial investigations in keratitis at the Sydney Eye Hospital.

We investigated 107 cases of presumed microbial keratitis amongst patients presenting to the Sydney Eye Hospital between October 1986 and August 1988 to determine the frequency of infection, the common causative organisms and those factors that predispose to corneal infection. We found that 95% of culture-proven cases were caused by bacteria and that Staphylococcus epidermidis and Corynebacterium sp. accounted for 42.5% of these cases. All bacteria (except Staphylococcus epidermidis and Mycobacterium chelonae) were sensitive to gentamicin. In 62.6% of cases, cultures for bacteria and fungi were negative. Retrospective review of the clinical records of these patients showed that herpes simplex virus, contact lens wear, staphylococcal marginal keratitis and recurrent erosion were important causes of keratitis in this group.

Thermal and water source effects upon the stability of enteroviruses in surface freshwaters.

The long-term survival of three human enterovirus serotypes, Coxsackievirus B3, echovirus 7, and poliovirus 1 was examined in samples of surface freshwater collected from five sites of physically different character. These were an artificial lake created by damming a creek, a small groundwater outlet pond, both a large- and a medium-sized river, and a small suburban creek. Survival was studied at temperatures of -20, 1, and 22 degrees C. The average amount of viral inactivation was 6.5-7.0 log10 units over 8 weeks at 22 degrees C, 4-5 log10 units over 12 weeks at 1 degree C, and 0.4-0.8 log10 units over 12 weeks at -20 degrees C. The effect of incubation temperature upon viral inactivation rate was statistically significant (p less than 0.00001). As determined by pairing tests, survival was also significantly related to both viral serotype and water source at each of the three incubation temperatures (p less than or equal to 0.05). Efforts were made to determine whether the rate of viral inactivation observed at the different incubation temperatures was related to characteristics inherent to the water that was collected from the different locations. The characteristics examined included physical and chemical parameters, indigenous bacterial counts, and the amount of bacterial growth that the waters would support (measured as the maximum number of generations which seeded bacteria could undergo after being placed into either pasteurized or sterile-filtered water samples). Analysis of viral inactivation rate versus these characteristics revealed three apparent effectors of viral persistence.(ABSTRACT TRUNCATED AT 250 WORDS)

Nonabsorbable suture material in corneoscleral sections--a comparison of novafil and nylon.

We compared a newly available nonabsorbable monofilament ophthalmic suture, 9/0 Novafil (Davis & Geck), with 10/0 nylon (Alcon), currently the most popular suture for closure of corneoscleral sections. Surgery was performed on nine rats and ten rabbits. In each case a 120 degrees corneoscleral section was made in each eye and closed with interrupted sutures of 9/0 Novafil in one eye and 10/0 nylon in the other. We compared their handling qualities during surgery, as well as their effect on postoperative wound inflammation. In addition we examined the suture material from each eye of the rats by scanning electron microscopy (SEM) after 3 months, and we compared the surgically induced astigmatism in the rabbits in the two suture groups. Both suture materials were easy to handle and well tolerated. Nylon sutures from six of the eight rat eyes studied showed SEM evidence of surface disintegration after 3 months, whereas all the Novafil sutures remained intact.