Electromyographic signals and the starting threshold voltage of orbicularis oris muscle in healthy rhesus monkeys / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the characteristics of electromyography (EMG) signals and the starting threshold voltages of the orbicularis oris muscles (OOM) in healthy rhesus monkeys under different muscle movement conditions. Methods: The EMG signals and the starting threshold voltages at different time points in 4 healthy rhesus monkeys were acquired and recorded with EMG device and evoked potentiometer. The voltage amplitude variation of EMG signals was analyzed, and the voltage amplitude range of EMG signals at the beginning of OOM contraction was established. The data were statistically analyzed by one-way ANOVA. Results: The EMG of OOM in healthy monkeys in the quiet, natural and continuous mouth-closed state was linear and relatively stable, and the absolute value fluctuated between 15 and 50 μV. The EMG waveform increased rapidly during the natural lip contraction movement, and its amplitude fluctuated greatly, with the highest absolute value of the peak value reaching hundreds of microvolts. The amplitude of EMG induced by continuous mouth closure was more than thousands of microvolts. There was no significant difference in EMG amplitudes of OOM in the healthy rhesus monkey under quiet and continuous lip closure at different time points (P>0.05). There was no significant difference in threshold voltages in the state of natural lip contraction of bilateral OOM at different time points (average range: 57.17-57.47 μV) in the healthy rhesus monkeys (P>0.05). There was no significant difference in threshold voltages of OOM induced by bilateral OOM at different time points(average range: 55.38-55.99 μV) in the healthy rhesus monkeys(P>0.05). There were significant differences in the absolute values of EMG amplitudes of OOM between the three lip movement modes: (30.67±8.72) μV in quiet and natural continuous lip closure (475.12±54.72) μV in natural lip contraction, and (921.22±312.79) μV in the induced persistent lip closure, with t values of -8.48, -9.35 and -5.01 respectively, all P<0.001. Conclusions: The EMG signals of OOM show different characteristics under different muscle movement conditions, which can be used as a basis for computer to judge and recognize the movement conditions of OOM. The upper limits of the EMG threshold voltage values of OOM under different motion states are 55-60 μV.

Epidemiological investigation of allergic rhinitis in central cities and countrysides of Inner Mongolia region / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the prevalence of allergic rhinitis (AR) in 3 central cities (Chifeng, Hohhot, Ordos) and the surrounding rural areas of Inner Mongolia region, and to look for possible risk factors related to the disease. Methods: From March to October of 2019, a multi-stage stratified random sampling epidemiological survey was conducted in Chifeng, Hohhot, Ordos and rural areas. The AR-related factors of the population were obtained in the form of face-to-face questionnaire survey, and the skin prick test (SPT) was taken for the participants. AR disease was diagnosed according to the "Guidelines for the Diagnosis and Treatment of Allergic Rhinitis (2015, Tianjin)". The daily airborne pollen situation in the three regions was monitored during the same period. SPSS 23.0 was used to analyze all survey results. Results: A total of 6 818 questionnaires were recovered, with 6 393 valid questionnaires. The self-reported prevalence of AR was 27.72% (1 772/6 393) and the confirmed prevalence of AR was 17.10% (1 093/6 393). The prevalence of perennial AR was 1.83% (117/6 393) while the prevalence of seasonal AR was 15.27% (976/6 393). The prevalence of AR diagnosed in females was higher than that in males (19.19% vs 15.34%, χ²=16.594, P<0.001) and the prevalence of females in the two age groups of 36-45 years and 46-55 years was significantly higher than that of males (18.17% vs 9.73%, 14.13% vs 7.25%, χ2 value was 23.848, 18.772, respectively, all P<0.001). The prevalence of confirmed diagnoses in ethnic minorities was higher than that of Han nationality, and the prevalence of confirmed diagnoses in urban areas was higher than that in rural areas (23.13% vs 16.20%, 27.27% vs 9.71%, χ2 value was 24.516, 336.024, respectively, all P<0.001). The main nasal symptoms of AR patients were sneezing (91.31%), nasal congestion (85.91%) and nasal itching (85.00%). The most common concomitant disease of AR was allergic conjunctivitis (73.99%). Asthma (OR=6.629), food allergy (OR=3.236), drug allergy (OR=1.786), application of antibiotics (OR=1.553), recent home decoration (OR=2.307), and smoking (OR=1.322) were the AR related risk factors. The highest proportion of SPT positive reactions was Artemisia annua (80.15%). The peak period of clinical symptoms of AR patients in Inner Mongolia region was July to September, which was consistent with the second peak period of airborne pollen monitoring. Conclusions: The prevalence of AR in central cities and the surrounding rural areas of Inner Mongolia region is 17.10%, and Artemisia species is the most important pollen allergen in this area. History of asthma, food allergy, drug allergy, antibiotic use, home decoration and smoking history are the related risk factors for AR.

Research on the electromyographic signals of orbicularis oculi muscle of rabbit / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>The 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.</p><p><b>RESULTS</b>The 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).</p><p><b>CONCLUSIONS</b>OOM 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.</p>