Using 3 non-invasive tests, abnormalities of cardiovascular reflex function were found in 7 of 15 patients with achalasia. Abnormalities of heart rate responses to the Valsalva maneuver, deep breathing, and standing w...Using 3 non-invasive tests, abnormalities of cardiovascular reflex function were found in 7 of 15 patients with achalasia. Abnormalities of heart rate responses to the Valsalva maneuver, deep breathing, and standing were noted in patients with autonomic neuropathy defect. The findings are consistent with the hypothesis that an abnormality of vagal function may contribute to the pathogenesis of achalasia.展开更多
Adolescent idiopathic scoliosis (AIS) is an agnogenic structural scoliosis occurring in adolescence, and the main diagnostic criteria is coronal Cobb angle >10°in total spine X-ray. Studies have shown that AIS...Adolescent idiopathic scoliosis (AIS) is an agnogenic structural scoliosis occurring in adolescence, and the main diagnostic criteria is coronal Cobb angle >10°in total spine X-ray. Studies have shown that AIS may be associated with abnormal postural reflexes, vestibular system is an important component of postural reflexes and its mechanism in the occurrence and development of scoliosis has received wide attention in recent years. In the study, the research progress on the role of abnormal vestibular reflexes in the pathogenesis of AIS was mainly introduced to help the clinicians better understand the pathogenesis of AIS and provide new ideas for AIS study.展开更多
BACKGROUND Electroacupuncture(EA) at ST36 can significantly improve gastrointestinal symptoms, especially in promoting gastrointestinal motility. The automatic nervous system plays a main role in EA, but few studies e...BACKGROUND Electroacupuncture(EA) at ST36 can significantly improve gastrointestinal symptoms, especially in promoting gastrointestinal motility. The automatic nervous system plays a main role in EA, but few studies exist on how vagovagal and sympathetic reflexes affect EA to regulate gastrointestinal motility.AIM To study the role of vagovagal and sympathetic reflexes in EA at ST36, as well as the associated receptor subtypes that are involved.METHODS Gastric motility was measured with a manometric balloon placed in the gastric antrum area in anesthetized animals. The peripheral nervous discharge was measured using a platinum electrode hooking the vagus or greater splanchnic nerve, and the central nervous discharge was measured with a glass microelectrode in the dorsal motor nucleus of the vagus(DMV). The effects and mechanisms of EA at ST36 were explored in male Sprague-Dawley rats which were divided in to a control group, vagotomy group, sympathectomy group, and microinjection group [including an artificial cerebrospinal fluid group, glutamate(L-Glu) group, and γ-aminobutyric acid(GABA) group] and in genetically modified male mice [β1β2 receptor-knockout(β1β2^(-/-)) mice, M2M3 receptorknockout(M2M3^(-/-)) mice, and wild-type control mice].RESULTS EA at ST36 promoted gastric motility during 30-120 s. During EA, both vagus and sympathetic nerve discharges increased, with a much higher frequency of vagus nerve discharge than sympathetic discharge. The gastric motility mediated by EA at ST36 was interdicted by vagotomy. However, gastric motility mediated by EA at ST36 was increased during 0-120 s by sympathectomy, which eliminated the delay effect of EA during 0-30 s, but it was lower than the control group during 30-120 s. Using gene knockout mice and their wild-type controls to explore the receptor mechanisms, we found that EA at ST36 decreased gastric motility in M2/3^(-/-) mice, and promoted gastric motility in β1/2^(-/-) mice. Extracellular recordings showed that EA at ST36 increased spikes of the DMV. Microinjection of L-Glu into the DMV increased gastric motility, while EA at ST36 decreased gastric motility during 0-60 s, and promoted gastric motility during 60-120 s.Injection of GABA reduced or increased gastric motility, and reduced the promoting gastric motility effect of EA at ST36.CONCLUSION These data suggest that EA at ST36 modulates gastric motility via vagovagal and sympathetic reflexes mediated through M2/3 and β1/2 receptors, respectively.Sympathetic nerve activity mediated through β1/2 receptors is associated with an early delay in modulation of gastric motility by EA at ST36.展开更多
A multiple-legged robot is traditionally controlled by using its dynamic model.But the dynamic-model-based approach fails to acquire satisfactory performances when the robot faces rough terrains and unknown environmen...A multiple-legged robot is traditionally controlled by using its dynamic model.But the dynamic-model-based approach fails to acquire satisfactory performances when the robot faces rough terrains and unknown environments.Referring animals' neural control mechanisms,a control model is built for a quadruped robot walking adaptively.The basic rhythmic motion of the robot is controlled by a well-designed rhythmic motion controller(RMC) comprising a central pattern generator(CPG) for hip joints and a rhythmic coupler(RC) for knee joints.CPG and RC have relationships of motion-mapping and rhythmic couple.Multiple sensory-motor models,abstracted from the neural reflexes of a cat,are employed.These reflex models are organized and thus interact with the CPG in three layers,to meet different requirements of complexity and response time to the tasks.On the basis of the RMC and layered biological reflexes,a quadruped robot is constructed,which can clear obstacles and walk uphill and downhill autonomously,and make a turn voluntarily in uncertain environments,interacting with the environment in a way similar to that of an animal.The paper provides a biologically inspired architecture,with which a robot can walk adaptively in uncertain environments in a simple and effective way,and achieve better performances.展开更多
AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups ...AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups to assess pupillary responses under varying light intensities(100,250,500 lx)and pharmacological interventions(1%atropine,1%cyclopentolate,1%tropicamide,or 2%pilocarpine).Baseline pupil size and eccentricity were recorded using a non-contact Python-based imaging system integrating edge detection and pixel-to-distance conversion.Direct illumination effects were measured at sequential time points,followed by drug administration and longitudinal tracking of pupillary changes.The protocol was repeated at 12wk of age for developmental comparisons.Postexperiment,enucleated eyes were analyzed to evaluate in vitro vs in vivo differences.RESULTS:Significant age-dependent differences in pupil dynamics were observed.Both 2-and 12-week-old guinea pigs exhibited marked pupil constriction under direct illumination(P<0.001),with decreased eccentricity post-constriction(P<0.001).Indirect illumination caused inconsistent pupil size changes(2-week:P=0.68;12-week:P=0.49).Pharmacologically,atropine,cyclopentolate,and tropicamide induced pupil dilation(P<0.001),whereas pilocarpine caused constriction(P<0.001).All drug groups showed reduced eccentricity(P<0.001).In vivo/in vitro comparisons revealed significant structural differences.CONCLUSION:This study investigates pupillary responses in developing guinea pigs,revealing a direct pupillary light reflex(PLR)with light intensity-dependent responses,while indirect PLR was undetectable.The differential effects of muscarinic modulators on pupillary responses underscore the critical role of cholinergic signaling in ocular accommodation,with age-related variations in sensitivity.Additionally,a novel non-contact measurement methodology achieved a precision of 0.01 mm for pupillary quantification,enhancing accuracy in ocular studies.展开更多
Frank and Fourtes showed the first strong evidence that the amplitude of the excitatory postaynaptic potential of a motor neuron could be diminished by presynaptie inhibiton. After that, a lot of studies concerning pr...Frank and Fourtes showed the first strong evidence that the amplitude of the excitatory postaynaptic potential of a motor neuron could be diminished by presynaptie inhibiton. After that, a lot of studies concerning presynaptic inhibition were published. Up to now, there have been three ways of measuring the primary展开更多
In this article,we review the study by Jin et al,which examined the role of intestinal glucagon-like peptide-1(GLP-1)in counterregulatory responses to hypoglycemia in patients with type 1 diabetes mellitus(T1DM).With ...In this article,we review the study by Jin et al,which examined the role of intestinal glucagon-like peptide-1(GLP-1)in counterregulatory responses to hypoglycemia in patients with type 1 diabetes mellitus(T1DM).With the global rise of T1DM,there is an increased burden on society and healthcare systems.Due to insulin therapy and islet dysfunction,T1DM patients are highly vulnerable to severe hypoglycemia,a leading cause of mortality.In healthy individuals,counterregulatory mechanisms restore blood glucose during hypoglycemia,but repeated episodes impair these responses.Jin et al demonstrated that overexpression of GLP-1 attenuates the sympathetic-adrenal reflex and disrupts the secretion of counterregulatory hormones such as glucagon during hypoglycemia,leading to counterregulatory dysfunction.These findings highlight the critical role of GLP-1 in the impaired counterregulatory response to hypoglycemia in T1DM patients and provide new insights into the potential application of GLP-1-related therapies in T1DM patients.展开更多
The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces....The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.展开更多
BACKGROUND Multiple sclerosis(MS)is known to affect many sensory systems,yet most auditory research in MS has focused on the afferent pathways,with relatively few studies examining efferent function.The brainstem is a...BACKGROUND Multiple sclerosis(MS)is known to affect many sensory systems,yet most auditory research in MS has focused on the afferent pathways,with relatively few studies examining efferent function.The brainstem is a common site for MS plaques,and the medial olivocochlear(MOC)system is located in the superior olivary complex(SOC)of the brainstem.The cochlear nuclei are also involved in the MOC reflex arc.Additionally,the temporal cortex can modulate the SOC and cochlear nucleus,so lesions in the brainstem or temporal cortex may affect the MOC reflex in MS.AIM To investigate efferent auditory system activity in patients with multiple sclerosis via the MOC reflex.METHODS The study included 50 patients with MS and 50 healthy controls.Patients with MS were divided into three subgroups according to cranial magnetic resonance imaging findings:Patients with brainstem lesions(Group 1,n=20);patients with temporal cortex lesions without brainstem involvement(Group 2,n=20);and patients without any lesions in the brainstem or temporal cortex(Group 3,n=10).Tympanometry,acoustic stapedial reflex thresholds,pure-tone audiometry,and transientevoked otoacoustic emission(TEOAE)tests(with and without contralateral noise)were performed for all participants.RESULTS There was no significant difference in pure-tone hearing thresholds or baseline TEOAE amplitudes between the MS and control groups,indicating normal cochlear function in patients with MS;however,MOC reflex suppression was significantly reduced in patients with MS compared to controls(P=0.021).In particular,Group 1(MS with brainstem lesions)showed the lowest mean suppression values,which was significantly lower than that of Group 2 and the control group(P=0.002).By contrast,Group 2 and Group 3 did not significantly differ from controls.Additionally,patients with MS exhibited a sex difference in MOC function:Male patients had significantly lower suppression compared to female patients both within Group 1 and in the MS group as a whole.CONCLUSION The findings indicate that the efferent auditory system(specifically the MOC reflex)is affected by MS.MOC reflex activity was most significantly decreased in patients with MS with brainstem lesions,while temporal cortex lesions alone did not appear to notably impair the MOC reflex.Diminished MOC activity may underlie various auditory difficulties in patients with MS(e.g.,hearing in noise),and loss of efferent suppression could contribute to symptoms such as hyperacusis or tinnitus in this population.Further studies are needed to better understand the relationship between MOC dysfunction and auditory symptoms in MS,as well as the potential diagnostic value of MOC testing in MS.展开更多
Objective:To investigate the suppressive effect of dexmedetomidine on the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia and its impact on vital signs.Methods:A total of 60...Objective:To investigate the suppressive effect of dexmedetomidine on the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia and its impact on vital signs.Methods:A total of 60 pediatric patients undergoing elective surgery admitted to our hospital from January to August 2025 were selected and randomly divided into an observation group and a control group,with 30 cases in each group,using a random number table method.The control group received an intravenous infusion of 0.9% sodium chloride injection 30 minutes before the end of surgery,while the observation group received an intravenous pump infusion of dexmedetomidine(1μg/kg,diluted to 4μg/ml with normal saline).The severity of cough(graded from 0 to 3)and vital signs,including heart rate(HR),systolic blood pressure(SBP),diastolic blood pressure(DBP),and pulse oxygen saturation(SpO₂),were recorded 5 minutes before extubation,at the time of extubation,and 5 minutes after extubation in both groups.Results:The severity of cough in the observation group was significantly milder than that in the control group(P<0.05),with a significantly higher proportion of grade 0 cough in the observation group(23.33%vs 3.33%).At extubation and five minutes post-extubation,the observation group exhibited significantly lower HR,SBP,and DBP than the control group(P<0.05).In contrast,SpO_(2)levels remained comparable between the groups(P>0.05).Conclusion:Dexmedetomidine can effectively suppress the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia,reduce the severity of cough,stabilize hemodynamic parameters,and has no significant impact on respiratory function,demonstrating good clinical safety.展开更多
The cylindrical virtual cathode reflex triode is a new type of pulsed hard X-ray load,which has the advantages of simple structure,high radiation conversion efficiency,and simplicity in seriesparallel operation.This p...The cylindrical virtual cathode reflex triode is a new type of pulsed hard X-ray load,which has the advantages of simple structure,high radiation conversion efficiency,and simplicity in seriesparallel operation.This paper presents a method to reduce the impedance of the triode using a multiring cathode.The average electric field on the ring-cathode emission surface is enhanced due to edge effect,and the beam intensity is greatly increased in proportion to the square of the electric field strength.Multi-ring cathode is used to enlarge the emission area.Therefore,the reflex triode can work at lower impedance and generate a stronger beam under the same anode-cathode gap.In addition,the electric field enhancement of the cathode reduces the cathode emission stabilization time and enhances the operation stability of the triode.The effects of parameters such as ring width and ring gap on the triode impedance are simulated and studied.The cathode emission stabilization time and the X-ray conversion efficiency are compared.The design basis of cathode structure parameters and the impedance control method of the cylindrical virtual cathode reflex triode are given according to the simulations.展开更多
The adaptability of the central nervous system has been revealed in several model systems.Of particular interest to central nervous system-injured individuals is the ability for neural components to be modified for re...The adaptability of the central nervous system has been revealed in several model systems.Of particular interest to central nervous system-injured individuals is the ability for neural components to be modified for regain of function.In both types of neurotrauma,traumatic brain injury and spinal cord injury,the primary parasympathetic control to the gastrointestinal tract,the vagus nerve,remains anatomically intact.However,individuals with traumatic brain injury or spinal cord injury are highly susceptible to gastrointestinal dysfunctions.Such gastrointestinal dysfunctions attribute to higher morbidity and mortality following traumatic brain injury and spinal cord injury.While the vagal efferent output remains capable of eliciting motor responses following injury,evidence suggests impairment of the vagal afferents.Since sensory input drives motor output,this review will discuss the normal and altered anatomy and physiology of the gastrointestinal vagal afferents to better understand the contributions of vagal afferent plasticity following neurotrauma.展开更多
In this paper, we definde the dual semimodule and reflexive semimodule in the category of semimodules and completely generalize the results of dual modules and reflexive modules to the dual semimodules and reflexive s...In this paper, we definde the dual semimodule and reflexive semimodule in the category of semimodules and completely generalize the results of dual modules and reflexive modules to the dual semimodules and reflexive semimodules.展开更多
Objective To investigate the spike activities of cerebellar cortical cells in a computational network model con- structed based on the anatomical structure of cerebellar cortex. Methods and Results The multicompartmen...Objective To investigate the spike activities of cerebellar cortical cells in a computational network model con- structed based on the anatomical structure of cerebellar cortex. Methods and Results The multicompartment model of neuron and NEURON software were used to study the external influences on cerebellar cortical cells. Various potential spike patterns in these cells were obtained. By analyzing the impacts of different incoming stimuli on the potential spike of Purkinje cell, temporal focusing caused by the granule cell-golgi cell feedback inhibitory loop to Purkinje cell and spa- tial focusing caused by the parallel fiber-basket/stellate cell local inhibitory loop to Purkinje cell were discussed. Finally, the motor learning process of rabbit eye blink conditioned reflex was demonstrated in this model. The simulation results showed that when the afferent from climbing fiber existed, rabbit adaptation to eye blinking gradually became stable under the Spike Timing-Dependent Plasticity (STDP) learning rule. Conclusion The constructed cerebellar cortex network is a reliable and feasible model. The model simulation results confirmed the output signal stability of cerebellar cortex after STDP learning and the network can execute the function of spatial and temporal focusing.展开更多
Objective Endogenous nitric oxide (NO) has been implicated in the regulation of neuronal activity which mediates cardiovascular reflexes. However, there is controversy concerning the role of NO in the nucleus tractu...Objective Endogenous nitric oxide (NO) has been implicated in the regulation of neuronal activity which mediates cardiovascular reflexes. However, there is controversy concerning the role of NO in the nucleus tractus solitarius (NTS). The present study aims to elucidate the possible physiological role of endogenous NO in modulating the excitatory vagal afferent input to NTS neurons. Methods All the experiments in the rat were conducted under anaesthetic conditions. Ionophoresis method was used for the application of NO donor or nitric oxide synthase (NOS) inhibitor, and single unit recording method was employed to detect the effects of these applications on vagal afferentor cardio-pulmonary C-fibre reflex-evoked neuronal excitation in NTS. Results Ionophoresis applications of L-arginine (L-Arg), a substrate of NOS, and sodium nitroprusside (SNP), a NO donor, both attenuated the vagal afferent-evoked discharge by (51.5±7.6)% (n = 17) and (68.3±7.1)% (n = 9), respectively. In contrast, application of D-Arg at the same current exerted no overall effect on this input. Also, both L-Arg and SNP inhibited spontaneous firing of most of the recorded neurons. In contrast, ionophoresis application of NG-nitro-Larginine methyl ester (L-NAME) enhanced vagal afferent-evoked excitation by (66.3±11.4)% (n = 7). In addition, ionophoresis application of L-Arg and SNP significantly attenuated cardio-pulmonary C-fibre reflex-induced excitation in the tested NTS neurons. Conclusion Activation of local NO pathway in the NTS could suppress vagal afferent-evoked excitation, suggesting that NO is an important neuromodulator of visceral sensory input in the NTS.展开更多
As the overall population ages, driving-related accidents and injuries, associated with elderly drivers, have risen. Existing research about elderly drivers mainly focuses on factual data collection and analysis, indi...As the overall population ages, driving-related accidents and injuries, associated with elderly drivers, have risen. Existing research about elderly drivers mainly focuses on factual data collection and analysis, indicating the elderly's growing fatal accident rates and their different behaviours compared to younger drivers. However, few research has focused on design-led practical solutions to mitigate the elderly's growing fatal accidents, by consid- ering their usability and body conditions, afflicting the elderly, such as decreased vision, hearing, and reaction times. In this paper, first, current worldwide situations on growing fatal accident rates for elderly drivers is reviewed and the key impact factors are identified and discussed with regarding to usability and design trend in the automotive technology for elderly. Second, existing smart vehicle technology-based solutions to promote safe driving are explored and their pros and cons are discussed and anal- ysed. Most of solutions are not created by people with driving difficulties, which are caused by health problems most commonly afflicting the elderly. Thirdly, diverse design-led research activities are taken, such as a survey, observation, and interviews to gain new understanding of what kinds of driving problems elderly drivers have and demonstrate how new system concepts could be developed for the elderly's benefits. Finally, it is found that the elderly's low vision and late reaction are main factors causing their driving difficulties. Based on this finding, usable vehicle system design ideas have been proposed, by utilising facial expression sensing technology as a solution. The proposed solutions would ensure reducing both the elderly's driving problems and high fatal accident rates and provide a more enjoyable driving environment for the elderly population.展开更多
文摘Using 3 non-invasive tests, abnormalities of cardiovascular reflex function were found in 7 of 15 patients with achalasia. Abnormalities of heart rate responses to the Valsalva maneuver, deep breathing, and standing were noted in patients with autonomic neuropathy defect. The findings are consistent with the hypothesis that an abnormality of vagal function may contribute to the pathogenesis of achalasia.
基金Natural Science Youth Foundation of China(81501845)Youth Initial Funding of Changhai Hospital(CH201518).
文摘Adolescent idiopathic scoliosis (AIS) is an agnogenic structural scoliosis occurring in adolescence, and the main diagnostic criteria is coronal Cobb angle >10°in total spine X-ray. Studies have shown that AIS may be associated with abnormal postural reflexes, vestibular system is an important component of postural reflexes and its mechanism in the occurrence and development of scoliosis has received wide attention in recent years. In the study, the research progress on the role of abnormal vestibular reflexes in the pathogenesis of AIS was mainly introduced to help the clinicians better understand the pathogenesis of AIS and provide new ideas for AIS study.
基金Supported by the National Natural Science Foundation of China,No.81373749No.81574071,and No.81673883
文摘BACKGROUND Electroacupuncture(EA) at ST36 can significantly improve gastrointestinal symptoms, especially in promoting gastrointestinal motility. The automatic nervous system plays a main role in EA, but few studies exist on how vagovagal and sympathetic reflexes affect EA to regulate gastrointestinal motility.AIM To study the role of vagovagal and sympathetic reflexes in EA at ST36, as well as the associated receptor subtypes that are involved.METHODS Gastric motility was measured with a manometric balloon placed in the gastric antrum area in anesthetized animals. The peripheral nervous discharge was measured using a platinum electrode hooking the vagus or greater splanchnic nerve, and the central nervous discharge was measured with a glass microelectrode in the dorsal motor nucleus of the vagus(DMV). The effects and mechanisms of EA at ST36 were explored in male Sprague-Dawley rats which were divided in to a control group, vagotomy group, sympathectomy group, and microinjection group [including an artificial cerebrospinal fluid group, glutamate(L-Glu) group, and γ-aminobutyric acid(GABA) group] and in genetically modified male mice [β1β2 receptor-knockout(β1β2^(-/-)) mice, M2M3 receptorknockout(M2M3^(-/-)) mice, and wild-type control mice].RESULTS EA at ST36 promoted gastric motility during 30-120 s. During EA, both vagus and sympathetic nerve discharges increased, with a much higher frequency of vagus nerve discharge than sympathetic discharge. The gastric motility mediated by EA at ST36 was interdicted by vagotomy. However, gastric motility mediated by EA at ST36 was increased during 0-120 s by sympathectomy, which eliminated the delay effect of EA during 0-30 s, but it was lower than the control group during 30-120 s. Using gene knockout mice and their wild-type controls to explore the receptor mechanisms, we found that EA at ST36 decreased gastric motility in M2/3^(-/-) mice, and promoted gastric motility in β1/2^(-/-) mice. Extracellular recordings showed that EA at ST36 increased spikes of the DMV. Microinjection of L-Glu into the DMV increased gastric motility, while EA at ST36 decreased gastric motility during 0-60 s, and promoted gastric motility during 60-120 s.Injection of GABA reduced or increased gastric motility, and reduced the promoting gastric motility effect of EA at ST36.CONCLUSION These data suggest that EA at ST36 modulates gastric motility via vagovagal and sympathetic reflexes mediated through M2/3 and β1/2 receptors, respectively.Sympathetic nerve activity mediated through β1/2 receptors is associated with an early delay in modulation of gastric motility by EA at ST36.
基金supported by National Natural Science Foundation of China (Grant No. 50905012)the Fundamental Research Funds for the Central Universities of China (Grant No. 2012JBM088)
文摘A multiple-legged robot is traditionally controlled by using its dynamic model.But the dynamic-model-based approach fails to acquire satisfactory performances when the robot faces rough terrains and unknown environments.Referring animals' neural control mechanisms,a control model is built for a quadruped robot walking adaptively.The basic rhythmic motion of the robot is controlled by a well-designed rhythmic motion controller(RMC) comprising a central pattern generator(CPG) for hip joints and a rhythmic coupler(RC) for knee joints.CPG and RC have relationships of motion-mapping and rhythmic couple.Multiple sensory-motor models,abstracted from the neural reflexes of a cat,are employed.These reflex models are organized and thus interact with the CPG in three layers,to meet different requirements of complexity and response time to the tasks.On the basis of the RMC and layered biological reflexes,a quadruped robot is constructed,which can clear obstacles and walk uphill and downhill autonomously,and make a turn voluntarily in uncertain environments,interacting with the environment in a way similar to that of an animal.The paper provides a biologically inspired architecture,with which a robot can walk adaptively in uncertain environments in a simple and effective way,and achieve better performances.
文摘AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups to assess pupillary responses under varying light intensities(100,250,500 lx)and pharmacological interventions(1%atropine,1%cyclopentolate,1%tropicamide,or 2%pilocarpine).Baseline pupil size and eccentricity were recorded using a non-contact Python-based imaging system integrating edge detection and pixel-to-distance conversion.Direct illumination effects were measured at sequential time points,followed by drug administration and longitudinal tracking of pupillary changes.The protocol was repeated at 12wk of age for developmental comparisons.Postexperiment,enucleated eyes were analyzed to evaluate in vitro vs in vivo differences.RESULTS:Significant age-dependent differences in pupil dynamics were observed.Both 2-and 12-week-old guinea pigs exhibited marked pupil constriction under direct illumination(P<0.001),with decreased eccentricity post-constriction(P<0.001).Indirect illumination caused inconsistent pupil size changes(2-week:P=0.68;12-week:P=0.49).Pharmacologically,atropine,cyclopentolate,and tropicamide induced pupil dilation(P<0.001),whereas pilocarpine caused constriction(P<0.001).All drug groups showed reduced eccentricity(P<0.001).In vivo/in vitro comparisons revealed significant structural differences.CONCLUSION:This study investigates pupillary responses in developing guinea pigs,revealing a direct pupillary light reflex(PLR)with light intensity-dependent responses,while indirect PLR was undetectable.The differential effects of muscarinic modulators on pupillary responses underscore the critical role of cholinergic signaling in ocular accommodation,with age-related variations in sensitivity.Additionally,a novel non-contact measurement methodology achieved a precision of 0.01 mm for pupillary quantification,enhancing accuracy in ocular studies.
文摘Frank and Fourtes showed the first strong evidence that the amplitude of the excitatory postaynaptic potential of a motor neuron could be diminished by presynaptie inhibiton. After that, a lot of studies concerning presynaptic inhibition were published. Up to now, there have been three ways of measuring the primary
基金Supported by the National Natural Science Foundation of China,No.82400966Guangdong Basic and Applied Basic Research Foundation,No.2021A1515111025Science and Technology Projects in Guangzhou,No.2024A04J5170.
文摘In this article,we review the study by Jin et al,which examined the role of intestinal glucagon-like peptide-1(GLP-1)in counterregulatory responses to hypoglycemia in patients with type 1 diabetes mellitus(T1DM).With the global rise of T1DM,there is an increased burden on society and healthcare systems.Due to insulin therapy and islet dysfunction,T1DM patients are highly vulnerable to severe hypoglycemia,a leading cause of mortality.In healthy individuals,counterregulatory mechanisms restore blood glucose during hypoglycemia,but repeated episodes impair these responses.Jin et al demonstrated that overexpression of GLP-1 attenuates the sympathetic-adrenal reflex and disrupts the secretion of counterregulatory hormones such as glucagon during hypoglycemia,leading to counterregulatory dysfunction.These findings highlight the critical role of GLP-1 in the impaired counterregulatory response to hypoglycemia in T1DM patients and provide new insights into the potential application of GLP-1-related therapies in T1DM patients.
基金Supported by NSFC(No.12171062)the Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-JQX0004)+1 种基金the Chongqing Talent Support Program(No.cstc2024ycjh-bgzxm0121)Science and Technology Project of Chongqing Education Committee(No.KJZD-M202300503)。
文摘The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.
文摘BACKGROUND Multiple sclerosis(MS)is known to affect many sensory systems,yet most auditory research in MS has focused on the afferent pathways,with relatively few studies examining efferent function.The brainstem is a common site for MS plaques,and the medial olivocochlear(MOC)system is located in the superior olivary complex(SOC)of the brainstem.The cochlear nuclei are also involved in the MOC reflex arc.Additionally,the temporal cortex can modulate the SOC and cochlear nucleus,so lesions in the brainstem or temporal cortex may affect the MOC reflex in MS.AIM To investigate efferent auditory system activity in patients with multiple sclerosis via the MOC reflex.METHODS The study included 50 patients with MS and 50 healthy controls.Patients with MS were divided into three subgroups according to cranial magnetic resonance imaging findings:Patients with brainstem lesions(Group 1,n=20);patients with temporal cortex lesions without brainstem involvement(Group 2,n=20);and patients without any lesions in the brainstem or temporal cortex(Group 3,n=10).Tympanometry,acoustic stapedial reflex thresholds,pure-tone audiometry,and transientevoked otoacoustic emission(TEOAE)tests(with and without contralateral noise)were performed for all participants.RESULTS There was no significant difference in pure-tone hearing thresholds or baseline TEOAE amplitudes between the MS and control groups,indicating normal cochlear function in patients with MS;however,MOC reflex suppression was significantly reduced in patients with MS compared to controls(P=0.021).In particular,Group 1(MS with brainstem lesions)showed the lowest mean suppression values,which was significantly lower than that of Group 2 and the control group(P=0.002).By contrast,Group 2 and Group 3 did not significantly differ from controls.Additionally,patients with MS exhibited a sex difference in MOC function:Male patients had significantly lower suppression compared to female patients both within Group 1 and in the MS group as a whole.CONCLUSION The findings indicate that the efferent auditory system(specifically the MOC reflex)is affected by MS.MOC reflex activity was most significantly decreased in patients with MS with brainstem lesions,while temporal cortex lesions alone did not appear to notably impair the MOC reflex.Diminished MOC activity may underlie various auditory difficulties in patients with MS(e.g.,hearing in noise),and loss of efferent suppression could contribute to symptoms such as hyperacusis or tinnitus in this population.Further studies are needed to better understand the relationship between MOC dysfunction and auditory symptoms in MS,as well as the potential diagnostic value of MOC testing in MS.
文摘Objective:To investigate the suppressive effect of dexmedetomidine on the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia and its impact on vital signs.Methods:A total of 60 pediatric patients undergoing elective surgery admitted to our hospital from January to August 2025 were selected and randomly divided into an observation group and a control group,with 30 cases in each group,using a random number table method.The control group received an intravenous infusion of 0.9% sodium chloride injection 30 minutes before the end of surgery,while the observation group received an intravenous pump infusion of dexmedetomidine(1μg/kg,diluted to 4μg/ml with normal saline).The severity of cough(graded from 0 to 3)and vital signs,including heart rate(HR),systolic blood pressure(SBP),diastolic blood pressure(DBP),and pulse oxygen saturation(SpO₂),were recorded 5 minutes before extubation,at the time of extubation,and 5 minutes after extubation in both groups.Results:The severity of cough in the observation group was significantly milder than that in the control group(P<0.05),with a significantly higher proportion of grade 0 cough in the observation group(23.33%vs 3.33%).At extubation and five minutes post-extubation,the observation group exhibited significantly lower HR,SBP,and DBP than the control group(P<0.05).In contrast,SpO_(2)levels remained comparable between the groups(P>0.05).Conclusion:Dexmedetomidine can effectively suppress the cough reflex during tracheal extubation in pediatric patients undergoing general anesthesia,reduce the severity of cough,stabilize hemodynamic parameters,and has no significant impact on respiratory function,demonstrating good clinical safety.
基金supported by National Natural Science Foundation of China(Nos.12027811 and 12275222)。
文摘The cylindrical virtual cathode reflex triode is a new type of pulsed hard X-ray load,which has the advantages of simple structure,high radiation conversion efficiency,and simplicity in seriesparallel operation.This paper presents a method to reduce the impedance of the triode using a multiring cathode.The average electric field on the ring-cathode emission surface is enhanced due to edge effect,and the beam intensity is greatly increased in proportion to the square of the electric field strength.Multi-ring cathode is used to enlarge the emission area.Therefore,the reflex triode can work at lower impedance and generate a stronger beam under the same anode-cathode gap.In addition,the electric field enhancement of the cathode reduces the cathode emission stabilization time and enhances the operation stability of the triode.The effects of parameters such as ring width and ring gap on the triode impedance are simulated and studied.The cathode emission stabilization time and the X-ray conversion efficiency are compared.The design basis of cathode structure parameters and the impedance control method of the cylindrical virtual cathode reflex triode are given according to the simulations.
基金the National Institutes of Health(NINDS 49177NINDS 105987)+1 种基金Craig H.Neilsen Foundation Senior Research award(295319)to GMHa grant from the National Institutes of Health(NINDS F31 NS 087834)to EMB。
文摘The adaptability of the central nervous system has been revealed in several model systems.Of particular interest to central nervous system-injured individuals is the ability for neural components to be modified for regain of function.In both types of neurotrauma,traumatic brain injury and spinal cord injury,the primary parasympathetic control to the gastrointestinal tract,the vagus nerve,remains anatomically intact.However,individuals with traumatic brain injury or spinal cord injury are highly susceptible to gastrointestinal dysfunctions.Such gastrointestinal dysfunctions attribute to higher morbidity and mortality following traumatic brain injury and spinal cord injury.While the vagal efferent output remains capable of eliciting motor responses following injury,evidence suggests impairment of the vagal afferents.Since sensory input drives motor output,this review will discuss the normal and altered anatomy and physiology of the gastrointestinal vagal afferents to better understand the contributions of vagal afferent plasticity following neurotrauma.
文摘In this paper, we definde the dual semimodule and reflexive semimodule in the category of semimodules and completely generalize the results of dual modules and reflexive modules to the dual semimodules and reflexive semimodules.
基金supported by the grants from National Natural Science Foundation of China (No. 10872069)
文摘Objective To investigate the spike activities of cerebellar cortical cells in a computational network model con- structed based on the anatomical structure of cerebellar cortex. Methods and Results The multicompartment model of neuron and NEURON software were used to study the external influences on cerebellar cortical cells. Various potential spike patterns in these cells were obtained. By analyzing the impacts of different incoming stimuli on the potential spike of Purkinje cell, temporal focusing caused by the granule cell-golgi cell feedback inhibitory loop to Purkinje cell and spa- tial focusing caused by the parallel fiber-basket/stellate cell local inhibitory loop to Purkinje cell were discussed. Finally, the motor learning process of rabbit eye blink conditioned reflex was demonstrated in this model. The simulation results showed that when the afferent from climbing fiber existed, rabbit adaptation to eye blinking gradually became stable under the Spike Timing-Dependent Plasticity (STDP) learning rule. Conclusion The constructed cerebellar cortex network is a reliable and feasible model. The model simulation results confirmed the output signal stability of cerebellar cortex after STDP learning and the network can execute the function of spatial and temporal focusing.
基金supported by Chongqing Science and Technology Commission (No.CHTC2007BA5025)Shanghai Pujiang Program (No.07PJ14015)Chongqing Educational Department (No. KJ0707021)
文摘Objective Endogenous nitric oxide (NO) has been implicated in the regulation of neuronal activity which mediates cardiovascular reflexes. However, there is controversy concerning the role of NO in the nucleus tractus solitarius (NTS). The present study aims to elucidate the possible physiological role of endogenous NO in modulating the excitatory vagal afferent input to NTS neurons. Methods All the experiments in the rat were conducted under anaesthetic conditions. Ionophoresis method was used for the application of NO donor or nitric oxide synthase (NOS) inhibitor, and single unit recording method was employed to detect the effects of these applications on vagal afferentor cardio-pulmonary C-fibre reflex-evoked neuronal excitation in NTS. Results Ionophoresis applications of L-arginine (L-Arg), a substrate of NOS, and sodium nitroprusside (SNP), a NO donor, both attenuated the vagal afferent-evoked discharge by (51.5±7.6)% (n = 17) and (68.3±7.1)% (n = 9), respectively. In contrast, application of D-Arg at the same current exerted no overall effect on this input. Also, both L-Arg and SNP inhibited spontaneous firing of most of the recorded neurons. In contrast, ionophoresis application of NG-nitro-Larginine methyl ester (L-NAME) enhanced vagal afferent-evoked excitation by (66.3±11.4)% (n = 7). In addition, ionophoresis application of L-Arg and SNP significantly attenuated cardio-pulmonary C-fibre reflex-induced excitation in the tested NTS neurons. Conclusion Activation of local NO pathway in the NTS could suppress vagal afferent-evoked excitation, suggesting that NO is an important neuromodulator of visceral sensory input in the NTS.
文摘As the overall population ages, driving-related accidents and injuries, associated with elderly drivers, have risen. Existing research about elderly drivers mainly focuses on factual data collection and analysis, indicating the elderly's growing fatal accident rates and their different behaviours compared to younger drivers. However, few research has focused on design-led practical solutions to mitigate the elderly's growing fatal accidents, by consid- ering their usability and body conditions, afflicting the elderly, such as decreased vision, hearing, and reaction times. In this paper, first, current worldwide situations on growing fatal accident rates for elderly drivers is reviewed and the key impact factors are identified and discussed with regarding to usability and design trend in the automotive technology for elderly. Second, existing smart vehicle technology-based solutions to promote safe driving are explored and their pros and cons are discussed and anal- ysed. Most of solutions are not created by people with driving difficulties, which are caused by health problems most commonly afflicting the elderly. Thirdly, diverse design-led research activities are taken, such as a survey, observation, and interviews to gain new understanding of what kinds of driving problems elderly drivers have and demonstrate how new system concepts could be developed for the elderly's benefits. Finally, it is found that the elderly's low vision and late reaction are main factors causing their driving difficulties. Based on this finding, usable vehicle system design ideas have been proposed, by utilising facial expression sensing technology as a solution. The proposed solutions would ensure reducing both the elderly's driving problems and high fatal accident rates and provide a more enjoyable driving environment for the elderly population.