Orbicularis Oculi Muscle Reinnervation Confers Corneal Protective Advantages over Static Interventions Alone in the Subacute Facial Palsy Patient.

BACKGROUND: Corneal protection is a priority in flaccid facial palsy patients. Denervation of the orbicularis oculi muscle results in weak palpebral closure and predisposes patients to severe corneal sequelae. While periorbital static procedures enhance corneal coverage in repose, voluntary closure is only regained through dynamic reinnervation of the muscle. This study aims to elucidate the added effect of dynamic reinnervation of the orbicularis oculi muscle on long-term corneal integrity as well as on dynamic closure of the palpebral aperture. METHODS: Retrospective review was performed on two groups of complete palsy patients: those who received solely periorbital static procedures and those who underwent concomitant orbicularis oculi muscle reinnervation and static lid procedures. Only patients with complete ophthalmic examinations were included. Corneal punctate epithelial erosions in addition to static and dynamic palpebral measurements were serially assessed preoperatively and postoperatively. RESULTS: Of 272 facial palsy patients, 26 fit the inclusion criteria. Eleven patients underwent combined muscle reinnervation involving facial-to-masseteric nerve coaptation in addition to static eye procedures, and 15 patients underwent solely static interventions. Analysis revealed a 65.3 percent lower mean punctate epithelial erosion score in reinnervation patients as compared with static patients when evaluated at more than 9 months postoperatively (p < 0.01). Reinnervation patients were also found to have 25.3 percent greater palpebral aperture closure (p < 0.05) and 32.8 percent higher closure velocity (p < 0.01) compared with static patients. CONCLUSION: In patients with subacute facial palsy, dynamic reanimation of the orbicularis oculi muscle with concomitant static interventions provides lasting corneal protection not seen in patients who receive solely static interventions. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Ocular Rosacea Causing Corneal Melt in an African American Patient and a Hispanic Patient.

PURPOSE: To discuss two rare presentations of ocular rosacea in a Hispanic patient and an African American patient with unusual ocular manifestations. CASE REPORT: Case 1: a 43-year-old Hispanic woman presented with right eye corneal perforation. Her prior medical history was significant for rosacea only, diagnosed clinically by a dermatologist. Her eye exam showed signs of bilateral ocular rosacea. An emergent full thickness tectonic corneal patch graft was done. The patient's bilateral eye symptoms improved one month after initiating rosacea treatment. Case 2: a 51-year-old African American man with long standing history of untreated rosacea presented with bilateral peripheral corneal thinning with neovascularization that led to right eye corneal perforation. Glue and bandage contact lens were applied. The patient did well 4 weeks after starting antibacterial, oral steroids, and rosacea treatment. DISCUSSION: Ocular rosacea can present in Hispanic and African American patients with severe manifestations such as corneal perforation.

Menthol increases human glioblastoma intracellular Ca2+, BK channel activity and cell migration.

This study examined the effect of menthol, an agonist for transient receptor potential melastatin 8 (TRPM8) ion channels, to increase intracellular Ca2+ concentration, [Ca2+]i, in human glioblastoma cells (DBTRG cells), which resulted in activation of the large-conductance Ca2+-activated K+ membrane ion channels (BK channels). Voltage ramps applied over 300 ms from -100 to 100 mV resulted in membrane currents with marked inwardly- and outwardly-rectifying components. Paxilline (2 microM) abolished the outwardly-rectifying current. Outwardly-rectifying on-cell patch currents were increased markedly by menthol (100 microM) added to the bath. The estimated on-cell conductance of these channels was 253 pS. Kinetic analysis showed that added menthol increased channel open probability and mean open frequency after 5 min. In a similar time course menthol increased [Ca2+]i, and this increase was abolished either by added paxilline, tetraethylammonium ion or by Ca2+-free external solution. Finally, menthol stimulated the rate of DBTRG cell migration into scratch wounds made in confluent cells, and this also was inhibited by paxilline or by tetraethylammonium ion. We conclude that menthol, a TRPM8 agonist, increases DBTRG cell [Ca2+]i that in turn activates membrane BK ion channels. Inhibition of BK channels by paxilline reverses menthol-stimulated increase of [Ca2+]i and of cell migration. Thus, BK channels function to maintain elevations in [Ca2+]i needed to sustain increases in DBTRG cell migration.

Future projections for Mexican faunas under global climate change scenarios.

Global climates are changing rapidly, with unexpected consequences. Because elements of biodiversity respond intimately to climate as an important driving force of distributional limitation, distributional shifts and biodiversity losses are expected. Nevertheless, in spite of modelling efforts focused on single species or entire ecosystems, a few preliminary surveys of fauna-wide effects, and evidence of climate change-mediated shifts in several species, the likely effects of climate change on species' distributions remain little known, and fauna-wide or community-level effects are almost completely unexplored. Here, using a genetic algorithm and museum specimen occurrence data, we develop ecological niche models for 1,870 species occurring in Mexico and project them onto two climate surfaces modelled for 2055. Although extinctions and drastic range reductions are predicted to be relatively few, species turnover in some local communities is predicted to be high (>40% of species), suggesting that severe ecological perturbations may result.