Biomedical subjects

M N Rhem

Publications and source records attributed to M N Rhem.

5 recordsLinked to original sources

PubMed2000

Epstein-Barr virus dacryoadenitis.

PURPOSE: To describe the clinical features of lacrimal gland inflammation associated with Epstein-Barr virus infection. METHODS: The clinical records, laboratory data, and radiographs of patients who had inflammation of one or both lacrimal glands that had begun less than 4 weeks previously were reviewed. RESULTS: Sixteen patients with dacryoadenitis were encountered between 1980 and 1996, a cumulative frequency of approximately one case per 10,000 new ophthalmic outpatients. Six individuals had serologic or other evidence of recent Epstein-Barr virus infection and were distinguished by the presence of regional lymphadenopathy, no purulent discharge, and a duration of symptoms of 6 weeks. CONCLUSION: Epstein-Barr virus is a probable cause of unilateral and bilateral dacryoadenitis in young adults.

Adolescent↗

PubMed2000

The collagen-binding adhesin is a virulence factor in Staphylococcus aureus keratitis.

A collagen-binding strain of Staphylococcus aureus produced suppurative inflammation in a rabbit model of soft contact lens-associated bacterial keratitis more often than its collagen-binding-negative isogenic mutant. Reintroduction of the cna gene on a multicopy plasmid into the mutant helped it regain its corneal adherence and infectivity. The topical application of a collagen-binding peptide before bacterial challenge decreased S. aureus adherence to deepithelialized corneas. These data suggest that the collagen-binding adhesin is involved in the pathogenesis of S. aureus infection of the cornea.

Adhesins, Bacterial↗

PubMed1996

Infectious crystalline keratopathy caused by Candida parapsilosis.

Infectious crystalline keratopathy is a chronic infection of the cornea, characterized by branching intrastromal opacities without inflammation. These changes are usually due to accumulations of bacterial colonies, most commonly viridans streptococci, but this entity has previously been reported in association with Candida albicans and Candida tropicalis. We present the case of a 66-year-old man who had previously undergone penetrating keratoplasty and developed infectious crystalline keratopathy due to Candida parapsilosis. Histopathology showed interlamellar accumulations of viable yeasts with no inflammation. Chronic topical corticosteroid use in this patient produced relative immunosuppression, allowing for the infection by Candida parapsilosis and the lack of inflammation in the cornea. The spectrum of causative organisms in infectious crystalline keratopathy continues to grow, emphasizing the need for laboratory evaluation in the management of this disorder.

Aged↗

PubMed1989

Effects of carbachol and acetylcholine on intraocular pressure after cataract extraction.

We compared the effect of carbachol and acetylcholine on intraocular pressure 24 hours after extracapsular cataract extraction. All agents were administered intracamerally at the time of surgery. Sixty patients scheduled for routine extracapsular cataract extraction and intraocular lens implantation were randomly assigned into one of three treatment groups: (1) carbachol, (2) acetylcholine, or (3) 0.5% balanced salt solution (placebo). Baseline intraocular pressures were determined the day before surgery, and postoperative pressures were measured approximately 24 hours after surgery. The group intraocular pressures averaged over preoperative and postoperative values were 21.06 mm Hg in the acetylcholine group, 19.36 mm Hg in the control group, and 17.30 mm Hg in the carbachol group. The average difference between preoperative and postoperative intraocular pressure measurements for the three groups were 7.33 mm Hg for the acetylcholine group, 8.73 mm Hg for the control group, and 2.20 mm Hg for the carbachol group. Only carbachol was significantly different from placebo on statistical subsequent testing. Carbachol is suggested as the agent of choice both for achieving intrasurgical miosis and prophylaxis of increasing intraocular pressure after cataract surgery.

Acetylcholine↗

PubMed1988

Effects of oxygen rearing on the electroretinogram and GFA-protein in the rat.

Albino rats were maintained in 60% oxygen from birth through 14 days of age. Control rats were simultaneously maintained in room air. At the end of the exposure period some animals from both groups were prepared for electroretinography and, following this analysis, were sacrificed for histological scrutiny of retinal vasculature. The rest of the rats were removed to room air and allowed to remain for various periods of time before electroretinography and sacrifice. Some of the retinas from the latter group were analyzed for the presence of glial fibrillary acidic protein (GFAP) by immunocytochemistry. Oxygen exposed rats had a permanent reduction of the b-wave of the electroretinogram (ERG). The a-waves of the two groups were indistinguishable. Control rats showed GFAP reactivity in the retinal astrocytes at all times. The oxygen-treated rats showed positive GFAP-staining in astrocytes at all times and in Müller cells from 2 weeks post-treatment through 8 weeks post-treatment, the last time point. Immunoblot analysis confirmed that the anti-GFAP reacted with a protein having a molecular weight and solubility characteristics like those of GFAP. These results indicate that Müller cells produce GFAP in response to oxygen-rearing in newborn rats and that this production occurs in the absence of any detectable neuronal cell death.

Animals↗