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Matthias Grueb

Publications and source records attributed to Matthias Grueb.

8 recordsLinked to original sources
PubMed2006

Muscarinic cholinoceptor-stimulated phosphatidyl inositol pathway in corneal epithelial and endothelial cells.

BACKGROUND: Muscarinic cholinoceptors are distributed widely in both the central and peripheral nervous system. The presence of muscarinic cholinoceptors in corneal tissue is well established. Previous reports have shown that corneal muscarinic cholinoceptors are of the m2 or m4 subtype. However, recent studies have indicated the presence of the m5 muscarinic cholinoceptor subtype in human corneal epithelium and endothelium. The aim of the study was to confirm the presence of the m5 cholinoceptor subtype in bovine corneal epithelium and endothelium and the activation of phosphatidyl inositol pathway by its stimulation. METHODS: Muscarinic m5 cholinoceptor sites, phosphatidyl inositol 4,5-biphosphate, inositol 1,4,5-triphosphate and protein kinase C, were studied using immunocytochemistry and immunofluorescence. Activation of protein kinase C after stimulation of the m5 muscarinic cholinoceptor subtype was measured using the HTS protein kinase C assay kit. RESULTS: Immunocytochemistry/immunofluorescence revealed the presence of the m5 muscarinic cholinoceptor subtype, phosphatidyl inositol 4,5-biphosphate and protein kinase C in bovine corneal epithelial and endothelial cells. In bovine corneal epithelium and endothelium, protein kinase C activity was stimulated by acetylcholine in a dose-dependent manner (P<0.0001). CONCLUSIONS: Our findings indicate that acetylcholine-induced stimulation of muscarinic m5 cholinoceptors activates the phosphatidyl inositol pathway in corneal epithelial and endothelial cells, resulting in increased protein kinase C activity. Further work will be needed to clear the physiologic role of this signaling pathway in corneal epithelium and endothelium.

Acetylcholine↗
PubMed2006

Transscleral diode laser cyclophotocoagulation as primary and secondary surgical treatment in primary open-angle and pseudoexfoliatve glaucoma. Long-term clinical outcomes.

BACKGROUND: Transscleral diode laser cyclophotocoagulation (TDLC) has been used successfully in the treatment of refractive glaucoma. However, little is known about TDLC as a primary or secondary surgical procedure in primary open-angle and pseudoexfoliative glaucoma. METHODS: In a retrospective chart review we analyzed 90 eyes (48 OD/42 OS) in 90 patients (mean age 75 years, range 60-92 years; 51 men/39 woman) with primary open-angle glaucoma (n=66) and pseudoexfoliative glaucoma (n=24) who consecutively underwent TDLC with a minimum follow-up of 24 months. In 24 eyes (26.7%) TDLC was the primary surgical treatment. Mean energy was 80 J (60-92 J). Success was defined as a final intraocular pressure (IOP) between 4 and 18 mmHg, a minimum IOP reduction of 20% and the absence of major complications. RESULTS: The overall success rate was 36.7% after 24 months. A mean of 1.3 procedures was performed per patient. No correlation between age and success rate (p=0.887) or gender and success rate (p=0.895) was seen. There was no significant reduction in antiglaucomatous medication (p=0.208), no significant loss of visual acuity (p=0.324) nor a significant relationship between loss of visual acuity and failure of treatment (p=0.201). In patients with primary open-angle glaucoma the success rate was 40.9% after 24 months; in patients with pseudoexfoliative glaucoma it was 25.0% after 24 months. There was no significant difference between primary open-angle glaucoma and pseudoexfoliative glaucoma (p=0.684). Previous ocular surgery decreased the success probability from 45.8 to 33.3% (p=0.001). Prolonged hypotonia occurred in 1 patient. No phthisis bulbi developed. CONCLUSIONS: Transscleral diode laser cyclophotocoagulation is an effective and safe method not only in the treatment of refractive glaucoma, but also as a primary surgical procedure in primary open-angle and pseudoexfoliative glaucoma. TDLC may be used more widely in glaucoma therapy, although further long-term studies have to confirm these findings.

Aged↗
PubMed2006

Muscarinic acetylcholine receptor subtypes in human corneal epithelium and endothelium.

BACKGROUND: Muscarinic acetylcholine receptors are located throughout the body. The demonstration of muscarinic receptors in corneal tissue has been inconsistent. Using freshly fixed human corneal tissue, we show a complete profile of muscarinic receptor subtypes in human corneal epithelium and endothelium. METHODS: Muscarinic receptor sites were studied using immunocytochemistry, immunofluorescence and immunoblotting. RESULTS: Antibodies to M2, M4 and M5 muscarinic receptor subtypes bound in human corneal epithelium and endothelium. No binding was found for antibodies to M1 and M3 muscarinic receptor subtypes. CONCLUSIONS: Our studies indicate the presence of M2, M4 and M5 muscarinic acetylcholine receptor subtypes in human corneal epithelium and endothelium. These receptors may play a role in the regulation of corneal homeostasis, other functions, like wound healing, or the pathogenesis of corneal diseases.

Adult↗
PubMed2006

Amphotericin B in the therapy of Candida glabrata endophthalmitis after penetrating keratoplasty.

PURPOSE: Candida glabrata is a rare cause of endophthalmitis after penetrating keratoplasty. Adequate therapy is still under discussion. With respect to severe complications and side effects of antifungal therapy, a substantial knowledge of sensitivity and resistance of the organism is necessary. METHODS: We report on a 26-year-old man with a hyperacute onset of the infection only 10 hours after surgery. A combined therapy for fluconazole and steroids administered over 3 months had shown no effect on intraocular infection. RESULTS: After topical and intracameral application of amphotericin B in combination with topical prednisolone 3 months after the onset of the endophthalmitis, the infection disappeared within 14 days, and the graft remained clear for 2 months. No toxic effects were noticed. CONCLUSION: In the case presented here, topical and intracameral application of amphotericin B was sufficient and safe in the therapy for C. glabrata endophthalmitis after penetrating keratoplasty. Although typically the intraocular infection is first noticed within the first 2 weeks, a hyperacute onset has to be considered.

Adult↗
PubMed2006

Monoamine receptors in human corneal epithelium and endothelium.

PURPOSE: Monoamine receptors are found throughout the body. Reports about the presence of monoamine receptors in the human cornea are inconsistent. METHODS: Immunohistochemistry, immunofluorescence and immunoblotting were used to localize monoamine receptor sites on human corneal epithelium and endothelium. RESULTS: Antibodies to alpha-1, beta-1 and beta-2 adrenergic receptors and to D1-like and 5HT-7 receptors were bound in corneal epithelium. Antibodies to alpha-1, alpha-2A, beta-1 and beta-2 adrenergic receptors and to 5HT-7 receptors were bound in corneal endothelium. CONCLUSIONS: Our data demonstrate the presence of several monoamine receptors in the human cornea. These receptors may play a role in the regulation of fluid transport or corneal homeostasis.

Adult↗