ObjectiveTo explore etiopathogenesis of slow transit constipation(STC). MethodsThe model of rat with “cathartic colon” was established, and the changes of colonic electromyography of the rat was examined. ResultsThe frequency and amplitude of slow wave in vivo of rats with cathartic colon was decreased markedly. Postmeal spike potential and duration was decreased, showing that gastrocolonic reflex of rats colon was decreased.ConclusionLong term abuse of stimulant laxuatives could damage enteric nervous system and accelerate the pathological changes of STC.
ObjectiveTo probe the clinical features and the characteristics of radiography and electroencephalogram (EEG) of tuberous sclerosis complex(TSC) in children with epilepsy. MethodsThe clinical data of the TSC cases with epilepsy were collected from inpatients in Jiangxi Children's Hospital from Jan. 2013 to Oct. 2015. ResultsAmong the 26 cases, 21 cases(21/26, 80.77%) involved abnormalities of the skin. Of these patients, there were 10 cases with hypomelanotic macules, 7 cases with café au lait spots and 4 cases with facial angiofibromas. There were no significant difference among the different age groups. In addition, there were 8 cases (8/26, 30.77%) with spasm seizures, of whom 3 cases had partial seizure, 10 cases (10/26, 38.46%) with complex partial seizure, 5 cases(5/26, 19.23%) with secondary generalized seizure, 2 cases(2/26, 7.69%) with tonic-clonic seizure and one case with Lennox-Gastaut syndrom(1/26, 3.85%). The average onset age of the epileptic spasms group were younger than those of the other epilepsy groups (t=2.143, P=0.042). EEG monitoring demonstrated hypsarrhythmia in 7 cases (7/26, 26.92%) in the interictal EEG, focal epileptic discharges in 11 cases (11/26, 42.31%), multifocal discharges in 5 cases, the slow background activity in 2 cases and the normal EEG in one case. Cranial imaging demonstrated subependymal nodules (SEN) in 25 cases(25/26, 96.15%) was the most common. ConclusionThe clinical manifestations and seizure types of TSC in children, especially in infants and young children, were diverse and age-dependent. It was very important to improve understanding of the clinical features and related risks of TSC at various ages, which was helpful to diagnose TSC early.
The new mechanisms of automaticity controlled by the calcium and membrane clocks in sinoatrial node are helpful to revealing the sinus arrhythmia, but the present calcium dynamic model is only on the single cell level. In the present study, a central and peripheral single cell model was developed, and by exponentially changing the cell membrane capacitance, size, conductance and gap junction from the center to the periphery, a two-dimensional inhomogeneous sinus and atrial model was created on the basis of the anatomical structure. Five-point difference and finite element methods were used to process the internal grids and the borders. Irregular borders were defined by creating segment trial functions. Quantitative experiments suggested the consistency of the central and peripheral action potentials with related reports in amplitude, cycle length, maximum diastolic potential and upstroke velocity. Functions of the calcium and membrane clocks on the leading pacemaker site and upstroke velocity as well as the effects of the atrial premature beat on the sinus automaticity were also in good agreement with those in other studies. The developed model is helpful for deeply studying relative roles of the calcium and membrane clocks in automaticity and the relations with electrical activities in atrium. At the same time it will lay the foundation for building three-dimensional sinus and atrial organic models.
This article combines researches and experiments of mild cognitive impairment (MCI) from 2005 to 2018. It makes a conclusion among psychological evaluation, imaging studies, nerve electrophysiology, neural circuit and mental models, and concludes the changes of patients with MCI, which helps to make a definite diagnosis of MCI in clinical practice. Due to the research above we can find the suitable way to improve the sensitivity and specificity of discovery of MCI, improve the predictive power of its development, and intervene potential Alzheimer’s disease effectively.
Atrial fibrillation (AF) is the most common arrhythmia in clinic, which can cause hemodynamic changes, heart failure and stroke, and seriously affect human life and health. As a self-promoting disease, the treatment of AF can become more and more difficult with the deterioration of the disease, and the early prediction and intervention of AF is the key to curbing the deterioration of the disease. Based on this, in this study, by controlling the dose of acetylcholine, we changed the AF vulnerability of five mongrel dogs and tried to assess it by analyzing the electrophysiology of atrial epicardium under different states of sinus rhythm. Here, indices from four aspects were proposed to study the atrial activation rule. They are the variability of atrial activation rhythm, the change of the earliest atrial activation, the change of atrial activation delay and the left-right atrial dyssynchrony. By using binary logistic regression analysis, multiple indices above were transformed into the AF inducibility, which were used to classify the signals during sinus rhythm. The sensitivity, specificity and accuracy of classification reached 85.7%, 95.8% and 91.7%, respectively. As the experimental results show, the proposed method has the ability to assess the AF vulnerability of atrium, which is of great clinical significance for the early prediction and intervention of AF.
As the most efficient perception system in nature, the perception mechanism of the insect (such as honeybee) antennae is the key to imitating the high-performance sensor technology. An automated experimental device suitable for collecting electrical signals (including antenna reaction time information) of antennae was developed, in response to the problems of the non-standardized experimental process, interference of manual operation, and low efficiency in the study of antenna perception mechanism. Firstly, aiming at the automatic identification and location of insect heads in experiments, the image templates of insect head contour features were established. Insect heads were template-matched based on the Hausdorff method. Then, for the angle deviation of the insect heads relative to the standard detection position, a method that calculates the angle of the insect head mid-axis based on the minimum external rectangle of the long axis was proposed. Eventually, the electrical signals generated by the antennae in contact with the reagents were collected by the electrical signal acquisition device. Honeybees were used as the research object in this study. The experimental results showed that the accuracy of template matching could reach 95.3% to locate the bee head quickly, and the deviation angle of the bee head was less than 1°. The distance between antennae and experimental reagents could meet the requirements of antennae perception experiments. The parameters, such as the contact reaction time of honeybee antennae to sucrose solution, were consistent with the results of the manual experiment. The system collects effectively antenna contact signals in an undisturbed state and realizes the standardization of experiments on antenna perception mechanisms, which provides an experimental method and device for studying and analyzing the reaction time of the antenna involved in biological antenna perception mechanisms.
Prolonged disorders of consciousness (pDOC) are pathological conditions of alterations in consciousness caused by various severe brain injuries, profoundly affecting patients’ life ability and leading to a huge burden for both the family and society. Exploring the mechanisms underlying pDOC and accurately assessing the level of consciousness in the patients with pDOC provide the basis of developing therapeutic strategies. Research of non-invasive functional neuroimaging technologies, such as functional magnetic resonance (fMRI) and scalp electroencephalography (EEG), have demonstrated that the generation, maintenance and disorders of consciousness involve functions of multiple cortical and subcortical brain regions, and their networks. Invasive intracranial neuroelectrophysiological technique can directly record the electrical activity of subcortical or cortical neurons with high signal-to-noise ratio and spatial resolution, which has unique advantages and important significance for further revealing the brain function and disease mechanism of pDOC. Here we reviewed the current progress of pDOC research based on two intracranial electrophysiological signals, spikes reflecting single-unit activity and field potential reflecting multi-unit activities, and then discussed the current challenges and gave an outlook on future development, hoping to promote the study of pathophysiological mechanisms related to pDOC and provide guides for the future clinical diagnosis and therapy of pDOC.