[Benign Tumors of the Eyelid].

Benign tumors of the eyelids are manifold. They can severely impair the anatomical unit of upper and lower eyelid, which basically serves to protect the eyeball. Furthermore, they can induce reduction of visual acuity or cause a subjectively more or less strong aesthetic disturbance of appearance.

Induction of neoplasia after deep anterior lamellar keratoplasty in a CXL-treated cornea.

Purpose: Corneal collagen crosslinking (CXL) with ultraviolet-A energy plus riboflavin has become a ubiquitous treatment in early keratoconus, although its long-term safety is unknown. We describe severe sequelae in a CXL-treated patient after he underwent a standard deep anterior lamellar keratoplasty procedure.

Methods: In April 2009, a healthy 49-year-old male patient (R.

Corneal limbal microenvironment can induce transdifferentiation of hair follicle stem cells into corneal epithelial-like cells.

The aim of this study was to investigate the transdifferentiation potential of murine vibrissa hair follicle (HF) stem cells into corneal epithelial-like cells through modulation by corneal- or limbus-specific microenvironmental factors. Adult epithelial stem cells were isolated from the HF bulge region by mechanical dissection or fluorescence-activated cell sorting using antibodies to alpha6 integrin, enriched by clonal expansion, and subcultivated on various extracellular matrices (type IV collagen, laminin-1, laminin-5, fibronectin) and in different conditioned media derived from central and peripheral corneal fibroblasts, limbal stromal fibroblasts, and 3T3 fibroblasts. Cellular phenotype and differentiation were evaluated by light and electron microscopy, real-time reverse transcription-polymerase chain reaction, immunocytochemistry, and Western blotting, using antibodies against putative stem cell markers (K15, alpha6 integrin) and differentiation markers characteristic for corneal epithelium (K12, Pax6) or epidermis (K10).

Diabetic Goto Kakizaki rats as well as type 2 diabetic patients show a decreased diurnal serum melatonin level and an increased pancreatic melatonin-receptor status.

There are functional inter-relationships between the beta cells of the endocrine pancreas and the pineal gland, where the synchronizing circadian molecule melatonin originates. The aim of this study was to elucidate a putative interaction between insulin and melatonin in diabetic patients and a diabetic rat model. We analyzed glucose, insulin, and melatonin levels of type 2 patients, as well as type 2 diabetic Goto Kakizaki (GK) rats by radioimmunoassay.

Receptor (MT(1)) mediated influence of melatonin on cAMP concentration and insulin secretion of rat insulinoma cells INS-1.

Recent functional, autoradiographic, and molecular investigations have shown that the pineal secretory product melatonin reduces the forskolin-stimulated insulin secretion from isolated pancreatic islets of neonate rats. Autoradiographic and binding studies as well as reverse transcriptase-polymerase chain reaction (RT-PCR) experiments proved that these effects are mediated through specific, high-affinity pertussis-toxin-sensitive Gi-protein-coupled MT(1) receptors and subsequent inhibition of the adenylyl cyclase/cyclic adenosine monophosphate (cAMP) system. This hypothesis was proved by blocking the intracellular signal transduction pathway using the non-hydrolyzable guanosine triphosphate analog guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) or the competitive melatonin receptor antagonist luzindole.