Blockage of the habenular nucleus can eliminate dyspnea induced by electrostimulation of the insular cortex

BACKGROUND： The insular cortex and habenular nucleus may be a regulatory center for obstructive sleep apnea syndrome, and dyspnea may be caused by insular cortex activity. The insular cortex is a cortical representation of obstructive sleep apnea syndrome. The habenular nucleus is a station for descending insular cortex activity. OBJECTIVE： Through actively stimulating the rat insular cortex, to observe rat respiratory movement, myoelectric activities of genioglossus, arterial partial pressure of oxygen, partial pressure of carbon dioxide and acidity-alkalinity, and to verify a hypothesis that the insular cortex is a superior-position regulation center, and the habenular nucleus is an inferior-position nervous nuclei of the insular cortex in patients with obstructive sleep apnea syndrome. DESIGN, TIME AND SETTING： The randomized, controlled animal study was performed at the Laboratory of Electrophysiology, Department of Physiology, Norman Bathune College of Medicine, Jilin University, China from September 2004 to June 2008. MATERIALS： We used L-glutamic acid （Dingguo Biological Product Research Center, Beijing, China）, lidocaine hydrochloride （Seventh Pharmacy Co., Ltd., Wuxi, China）, electric stimulator （Nihon Kohden, Japan）, and an AVL-OPTI blood gas analyzer （AVL Scientific Co., Roswell, GA, USA）. METHODS： The insular cortex of healthy adult Wistar rats underwent electrostimulation and L-glutamic acid stimulation to record changes in the myoelectric activity of genioglossus and respiratory movement. Some rats were injected with lidocaine to block the habenular nucleus before electrostimulation or L-glutamic acid stimulation. L-glutamic acid and lidocaine were injected by microelectrodes embedded in nuclear groups. MAIN OUTCOME MEASURES： Myoelectric activities of genioglossus, arterial partial pressure of oxygen, partial pressure of carbon dioxide and acidity-alkalinity were measured following apnea in rats undergoing electrostimulation in the insular cortex and following blockade of the habenular nucleus. RESULTS： Following electrostimulation and L-glutamic acid stimulation, rats developed apnea or respiratory rhythm disorders. Simultaneously, the amplitude of myoelectric activity of the genioglossus was reduced （P 〈 0.01 ）, and the electromyogram integral was decreased （P 〈 0.01）. Arterial blood gas analysis showed arterial blood acidosis, a decrease in pH （P 〈 0.05）, and an increase in the negative value of alkaline reserve （P 〈 0.01）. Lidocaine in the habenular nuclear blocked respiratory and other index changes after insular cortex stimulation. CONCLUSION： Dyspnea induced by stimulating the insular cortex may require the habenular nucleus. Paralysis of the habenular nucleus can completely eliminate insular cortex stimulation-induced dyspnea.

Extract from Buthus martensii Karsch is associated with potassium channels on glioma cells

Catilan extracted from Leiurus quinquestriatus is a specific ion channel blocker.It can specifically bind chloride channels of glioma cells and kill these tumor cells.The questions remain as to whether antigliomatin,the extract from scorpion venom of Buthus martensii Karsch in China,can inhibit glioma growth,and whether this inhibition is correlated with ion channels of tumor cells.The present study treated rat C6 glioma cells with 0.8,1.2,and 1.6 μg/mL antigliomatin for 20 hours.Whole-cell patch clamp technique showed that antigliomatin delayed rectifier potassium channels of C6 glioma cells.Antigliomatin inhibited tumor growth,which could potentially involve potassium channels of tumor cells.

Effects of antigliomatin from the scorpion venom of Buthus martensii Karsch on chloride channels on C6 glioma cells

Using whole-cell patch-clamp recordings, the effects of antigliomatin were observed on chloride channels on C6 glioma cells cultured in vitro. Antigliomatin was extracted from the venom of the scorpion Buthus martensii Karsch. Chloride channels are closed under normal osmotic pressure. When osmotic pressure was reduced to 120, 110 and 100 mV, the cell volume enlarged, chloride channels opened, and the chloride channel current increased. Three minutes after antigliomatin treatment, the chloride channel current decreased in a dose-dependent manner. These results show that antigliomatin extracted from the venom of the scorpion Buthus martensii Karsch diminishes chloride channel currents on C6 glioma cells.

Role of 5-hydroxytryptamine expression in cerebellar Purkinje cells in obstructive sleep apnea syndrome

In the present study, electrical stimulation to the rat insular cortex induced apnea or respiratory disturbance, reduced amplitude of genioglossal electromyogram, and decreased electromyogram integrals. In addition, arterial blood gas analysis showed arterial blood acidosis, reduced pH values, increased alkali reserve negative values, decreased peripheral blood 5-hydroxytryptamine content, and increased 5-hydroxytryptamine expression in cerebellar Purkinje cells. Following lidocaine injection to block the habenular nucleus, abnormalities in breath, genioglossal electromyogram, and blood gas values disappeared, and peripheral blood 5-hydroxytryptamine content returned to levels prior to electric stimulation. However, 5-hydroxytryptamine expression in cerebellar Purkinje cells remained high. The results suggested that 5-hydroxytryptamine expression in Purkinje cells did not correlate with ventilation function involving insular cortex and habenular nucleus.

5-hydroxytryptamine-mediated apnea caused by the habenular nucleus

5-hydroxytryptamine contributes to the control of activities of the dilator muscle in the upper respiratory tract, and is derived from the raphe nuclei, in which the habenular nucleus exerts a sustaJned inhibitory effect. In the present study, respiratory motion curve of the genJoglossus muscle and peripheral 5-hydroxytryptamine changes were observed following L-glutamate stimulation of the habenular nucleus of adult Wistar rats. Results showed that the rats had apnea and decreased plasma 5-hydroxytryptamine content after the neurons in habenular nucleus were excited. Genioglossus muscle electromyogram amplitude and integral were significantly reduced. The genioglossus myoelectric activity and respiratory motion curve were similar to obstructive sleep apnea syndrome, thus confirming that the habenular nucleus is the key nucleus involved in the pathogenesis of obstructive sleep apnea syndrome, and is the primary regulated center in the raphe nuclei. Stimulation of the habenular nucleus may suppress 5-hydroxytryptamine release and result in apnea, which is similar to obstructive sleep apnea syndrome.

Developing Rural Cooperative Finance with Reference to Experience of Foreign Countries

At present,rural credit cooperative is an essential part of rural financial system in China. Since the foundation of new China,especially since the reform and opening-up,rural credit cooperative has become the largest financial organization in rural areas. However,its operation mode needs further improvement and service functions are to be strengthened. Therefore,learning successful mode of rural cooperative finance in foreign countries has important theoretical and realistic significance for promoting development of China's rural cooperative finance.

Testing Operating Performance of Chinese Listed Firms before and after Cross-border M&As: The Role of Entrepreneurial Orientation

At a time when China encourages its firms to go overseas,especially to countries and regions involved in its"Belt and Road Initiative",and sets up a favorable domestic environment for innovation and entrepreneurship,this paper is a first trial looking along both the two dimensions to test whether Chinese firms’operating performance changes after cross-border merger and acquisition(CBM&A)activities,using entrepreneurial orientation(EO)as a moderating factor.The paper combines data from Chinese listed firms’annual reports,Chinese stock market financial statements database and the Zephyr database from 2001 to 2015 to examine how acquirers’operating performance changes after CBM&A activities using EO as a moderating factor.In order to test whether the results are affected by the stock market,this paper also defines abnormal return on equity(ROE)to detect abnormal operating performance.After these,the paper divides the sample into separate industry groups to see whether results will change.The results obtained for the whole sample show that the performance of Chinese listed firms is fluctuant after CBM&As within the sample years.It increases one year after the acquisition but drops two years later and then follows an increasing trend again.The moderating factor of EO is not significant for the sample as a whole.However,after dividing the sample into separate industry groups,it becomes clear that different industries have their own characteristics.EO helps Chinese listed firms to adjust to the post-acquisition situation and even to improve their performance to some extent in the metal mining industry and the business services industry.When ROE is substituted with abnormal ROE,the results do not change much.

Detection Scheme of Positive Sequence Components Based on Operation Period Delay Filter

Fast and accurate acquisition of positive sequence components of unbalanced grid voltage is an essential requirement to ensure the safety operation of the grid-connected inverter.To improve the extraction speed of positive sequence components of unbalanced voltage,this study proposes a sampling period delay filter(SPDF)to quickly separate positive and negative sequence components by delaying two sampling periods of grid voltage in dq frame.With the SPDF method,only one coordinate transformation is required and the computational burden can be reduced apparently.Then,the noise immunity performance of the proposed SPDF algorithm is investigated;and the corresponding solution,operation period delay filter(OPDF),can guarantee the desired fast response performance under the premise of limiting the amplified noise within the acceptable range.Finally,the feasibility and priority of the above two algorithms have been verified by the simulation and experimental results.