Acetylcholinesterase-positive and paraformaldehyde-induced-fluorescence-positive innervation in the upper eyelid of the sheep (Ovis aries)

Meibography: A review of techniques and technologies

Meibomian glands play a significant role in tear production by contributing lipids to the superficial tear film.(1) Dysfunction of the meibomian glands destabilizes tears resulting in evaporative dry eye.(2,3) Historically, the meibomian glands were assessed in an ex vivo fashion through histologic studies. However, innovations in ocular imaging have advanced significantly in recent decades to include meibography. Meibography is an imaging study developed 35 years ago exclusively for the purpose of observing the morphology of meibomian glands in vivo.(4,5) In this review of meibography, we briefly describe the etiology of meibomian gland dysfunction and then discuss various meibography techniques, technologies, and methods of image analysis. We close with a review of the literature, crediting various studies for the significant contributions made toward our current understanding of the meibomian glands.

Neurotransmitter influence on human meibomian gland epithelial cells

PURPOSE

A striking characteristic of the human meibomian gland is its rich sensory, sympathetic, and parasympathetic innervation, yet the functional relevance of these nerve fibers remains unknown. Acting on the hypothesis that neurotransmitters are released in the vicinity of the gland, act on glandular receptors, and influence the production, secretion, and/or delivery of meibomian gland secretions to the ocular surface, the goal in this study was to begin to determine whether neurotransmitters influence the meibomian gland.

METHODS

Immortalized human meibomian gland epithelial (SLHMG) cells were examined for the presence of vasoactive intestinal peptide (VIP) and muscarinic acetylcholine (mACh) receptor transcripts and proteins. Cells were also exposed to VIP, carbachol, forskolin, and/or 3-isobutyl-1-methylxanthine (IBMX) to determine whether these agents, alone or in combination, modulate the adenylyl cyclase pathway, the accumulation of intracellular free calcium ([Ca2+]i), or cell proliferation.

RESULTS

Results demonstrate that SLHMG cells transcribe and translate VIP and mACh receptors; VIP, with either IBMX or forskolin, activates the adenylyl cyclase pathway, and the effect of VIP and forskolin together is synergistic; both VIP and carbachol increase intracellular [Ca2+] in SLHMG cells; and VIP with forskolin stimulates SLHMG cell proliferation.

CONCLUSIONS

This study shows that parasympathetic neurotransmitters and their agonists influence the function of human meibomian gland epithelial cells. It remains to be determined whether this action alters the production, secretion, and/or delivery of meibum to the ocular surface.

Botulinum toxin A injection for primary and recurrent chalazia

BACKGROUND

To study the efficacy and safety of subcutaneous botulinum toxin A injections in the treatment of primary and recurrent chalazia.

METHODS

Prospective, placebo-controlled consecutive case-series trial. Sixty three patients were divided into two groups: group 1 consisting of 32 patients previously diagnosed with and treated for primary or recurrent chalazia with 2-5 international units (IU) in 0.2-0.5 ml of preserved saline solution of botulinum toxin injection, and group 2 consisting of 31 patients receiving placebo. The main outcome measures were localization and duration of the disease, size of chalazion before and after treatment, clinical resolution of chalazion, time to resolution, and complications of treatment.

RESULTS

There was a clinically and statistically significant between-group difference in the rate of therapeutic success and post-therapeutic chalazion regression, but not in the rate of complications.

CONCLUSIONS

Botulinum toxin A injection is effective and safe treatment for primary and recurrent chalazia. Lesion regression that did not respond to the average of two injections would benefit more from surgical excision or systemic antibiotic therapy.

S-100 protein immunoreactivity in the upper eyelid of the sheep Ovis aries

The aim of this work was to analyse the distribution pattern of S-100-immunoreactive elements in the upper eyelid of the sheep. This pattern may be of importance regarding the diagnosis and prognosis of eyelid tumours that are linked to deregulation of S-100 gene expression. Thirty upper eyelids taken from 15 adult male Ovis aries were studied by means of the peroxidase-antiperoxidase method for light microscopy. S-100-immunopositive cells were found in the eyelid edge. S-100-immunopositive steams and thinner fibres were found throughout the eyelid. These nerve processes typically were denser around glands, hair follicles and blood vessels. S-100-immunopositive elements may play a role as neuromodulator and also in the development of the vegetative innervation of the epithelium and its derivatives.