The deep cerebellar nuclei (DCN) integrate various inputs to the cerebellum and form the final cerebellar outputs critical for associative sensorimotor learning. However, the functional relevance of distinct neuronal subpopulations within the DCN remains poorly understood. Here, we examined a subpopulation of mouse DCN neurons whose axons specifically project to the ventromedial (Vm) thalamus (DCN^Vm neurons), and found that these neurons represent a specific subset of DCN units whose activity varies with trace eyeblink conditioning (tEBC), a classical associative sensorimotor learning task. Upon conditioning, the activity of DCN^Vm neurons signaled the performance of conditioned eyeblink responses (CRs). Optogenetic activation and inhibition of the DCN^Vm neurons in well-trained mice amplified and diminished the CRs, respectively. Chemogenetic manipulation of the DCN^Vm neurons had no effects on non-associative motor coordination. Furthermore, optogenetic activation of the DCN^Vm neurons caused rapid elevated firing activity in the cingulate cortex, a brain area critical for bridging the time gap between sensory stimuli and motor execution during tEBC. Together, our data highlights DCN^Vm neurons' function and delineates their kinematic parameters that modulate the strength of associative sensorimotor responses.
Animals ; Blinking ; Cerebellar Nuclei/physiology* ; Cerebellum ; Mice ; Neurons/physiology* ; Thalamus

PURPOSE: We investigated the incidence of exposure keratopathy, cornea protective changes in tear film such as corneal sensitivity, tear film stability, and tear secretion after frontalis suspension, and the correlation of these with lagophthalmos. METHODS: The corneal sensitivity test, tear film break-up time (tBUT) measurement, and basic secretion test were performed prospectively in patients who had undergone frontalis suspension. RESULTS: The mean lagophthalmos was highest at postoperative 1 week and then gradually decreased. There were no significant changes in corneal sensitivity, tBUT or tear secretion after surgery. No significant differences were found in those parameters between eyes with lagophthalmos of 3 mm or more and those less than 3 mm, nor did these parameters differ between eyes with clear cornea and exposure keratopathy. Only tBUT at postoperative 1 week was significantly shorter in eyes with lagophthalmos 3 mm or more than those less than 3 mm. The average level of lagophthalmos in eyes with exposure keratopathy (15/33 eyes, 45.4%) was more than 3mm at every follow-up period, which was significantly higher than for eyes with a clear cornea. CONCLUSIONS: Tear physiology tends to maintain normal function despite poor blinking induced by lagophthalmos. The cornea is thought to be protected by these functions of tear film. The factor most influential on cornea status was the level of lagophthalmos, and exposure keratopathy should be carefully examined during postoperative period in eyes with higher lagophthalmos, especially more than 3 mm.
Blinking ; Cornea ; Follow-Up Studies ; Humans ; Incidence ; Physiology ; Postoperative Period ; Prospective Studies ; Tears*

OBJECTIVETo study the features of electromyographic signals of orbicularis oculi muscle (OOM) of normal rabbits in various movement states, and to clarify relationships between functional actions of OOM and their electromyographic signals, hoping to obtain information concerning the electromyographic signals controlling OOM as reference for restoring the eye-closing function by artificial facial nerve prosthesis in patients with unilateral peripheral facial palsy.

METHODSThe electromyographic signals were extracted from OOM of normal rabbits by implanted microelectrodes through upper and lower eyelids. Then the features of these electromyographic signals were analyzed in the time domain and the frequency domain.

RESULTSThe peak values of the absolute electromyographic amplitude for natural continuous eye-opening event, natural continuous eye-closing state, natural eye-blinking movement and evoked eye-closing state were (28.8 ± 4.8) µV, (36.0 ± 4.7) µV, (398.8 ± 195.7) µV, and (715.4 ± 249.7) µV, respectively. The peak frequency values of the power spectrum density (PSD) of electromyographic signals for the four modes were (98 ± 17) Hz, (142 ± 22) Hz, (203 ± 58) Hz, and (349 ± 81) Hz, respectively. The electrical activities during the natural continuous eye-opening event and the natural continuous eye-closing state were stable and displayed low amplitudes. During the spontaneous blink state and the evoked eye-closing state, the electromyographic amplitudes markedly increased, and the increased level in the latter state was stronger than that in the former state. When rabbits continuously closed eyes or opened eyes, all of the peak values of the absolute voltage amplitudes were less than 50 µV. The absolute amplitude values of the starting site were between 50 µV and 60 µV during the spontaneous blink and the evoked eye-closing movements. The whole frequency band of the energy of PSD about OOM was between 0 Hz and 500 Hz, and the focus frequency range was between 20 Hz and 350 Hz.In the time domain, the difference was not significant for the electromyographic signals of OOM between the continuous eye-opening state and the continuous eye-closing movement (P > 0.05), but there were statistically significant differences in the other states for their pairwise comparisons (P < 0.05). In the frequency domain, there was no statistically significant difference for the peak frequency of PSD about the electromyographic signals when comparing the continuous eye-opening state with the continuous eye-closing event (P > 0.05). When comparing this item in the other movements with each other, however, the differences were statistically significant (P < 0.05).

CONCLUSIONSOOM relaxes when eyelid keeps continuously opening. The action of eyelid-closing is due to contraction of this muscle. Each state has its own features of the electromyographic signals for OOM, these features can be used as criteria for computers to judge and identify various movement states of OOM. However, it is difficult to distinguish the natural continuous eye-opening event from the natural continuous eye-closing state, based on the features of electromyographic signals in the time and frequency domain.

Animals ; Blinking ; Electromyography ; Eye Movements ; Eyelids ; innervation ; Facial Paralysis ; Male ; Muscle, Skeletal ; physiology ; Rabbits

PURPOSE: To evaluate the results of levator resection in patients with myopathic ptosis. METHODS: The medical records of consecutive patients who underwent levator resection surgery performed for myopathic ptosis between October 2009 and March 2013 were reviewed. Indications for surgery were ptosis obscuring the visual axis and margin-reflex distance < or =2 mm. Surgical success was defined as clear pupillary axis when the patient voluntarily opened his eye and margin-reflex distance > or =3 mm. We analyzed the effect of levator function and Bell's phenomenon on the rates of success and corneal complication. RESULTS: This series included six male and six female patients. Levator function was between 4 and 12 mm. We performed bilateral levator resection surgery in all patients. The mean follow-up time was 14.8 months (range, 6 to 36 months). No patient was overcorrected. Adequate lid elevation was achieved after the operation in 20 eyes. Ptosis recurred in three out of 20 eyes after adequate lid elevation was achieved. Our overall success rate was 70.8%. In three eyes with poor Bell's phenomenon, corneal irritation and punctate epitheliopathy that required artificial eye drops and ointments developed in the early postoperative period, although symptoms resolved completely within 2 months of the resection surgery. No patients required levator recession or any other revision surgery for lagophthalmos or corneal exposure after levator resection. CONCLUSIONS: Levator resection seems to be a safe and effective procedure in myopathic patients with moderate or good Bell's phenomenon and levator function greater than 5 mm.
Adult ; Aged ; Blepharoptosis/*surgery ; Blinking/physiology ; Female ; Humans ; Male ; Middle Aged ; Muscular Diseases/*surgery ; Oculomotor Muscles/*surgery ; *Ophthalmologic Surgical Procedures ; Postoperative Complications

OBJECTIVETo prepare a new dental topical anesthetics, lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome (LID-TAT-N), and to evaluate its transdermal properties and topical anesthesia effects.

METHODSLID-TAT-N was prepared using reverse-phase evaporation method, and lidocaine loaded conventional liposome (LID-CL) was prepared in the same manner as positive control. The diameter, ζ potential and encapsulation efficiency of LID-TAT-N and LID-CL were measured. The skin permeation of LID-TAT-N was examined, and compared with LID-CL and lidocaine injection (LID-IJ, as negative control), using a Franz diffusion cell mounted with depilated mouse skin in vitro for 12 hours. Each experiment was repeated six times. The anesthetic effect of the new topical anesthetic was investigated on the cornea of rabbits.

RESULTSThe mean diameter of LID-TAT-N was smaller than that of LID-CL [(152.7 ± 10.6) nm vs. (259.5 ± 15.5) nm, P < 0.01]. The 12 h cumulative permeation amount was significantly higher in LID-TAT-N group [(1 340.0 ± 97.5) µg · cm(-2)] than those of LID-CL and LID-IJ groups [(1 060.6 ± 80.2), (282.6 ± 65.1) µg · cm(-2), respectively, P < 0.05]. Rabbit corneal reflex results showed that LID-TAT-N had anesthetic effect and the duration of analgesia [(24.8 ± 2.8) min] was also longer than that of LID-IJ [(14.5 ± 2.3) min, P < 0.05].

CONCLUSIONSLID-TAT-N had good transdermal ability, and the advanced skin penetration feature can improve its tropical anesthetic effect.

Administration, Cutaneous ; Anesthesia, Dental ; Anesthetics, Local ; administration & dosage ; pharmacokinetics ; Animals ; Blinking ; drug effects ; physiology ; Cornea ; drug effects ; physiology ; Lidocaine ; administration & dosage ; pharmacokinetics ; Liposomes ; Mice ; Nanoconjugates ; administration & dosage ; chemistry ; Peptides ; Rabbits ; Skin ; metabolism ; Skin Absorption ; Trans-Activators ; administration & dosage ; chemistry ; pharmacokinetics