This study aims to explore the diagnosis in patients with Alzheimer's disease (AD) based on magnetic resonance (MR) images, and to compare the differences of bilateral hippocampus in classification and recognition. MR images were obtained from 25 AD patients and 25 normal controls (NC) respectively. Three-dimensional texture features were extracted from bilateral hippocampus of each subject. The texture features that existed significant differences between AD and NC were used as the features in a classification procedure. Back propagation (BP) neural network model was built to classify AD patients from healthy controls. The classification accuracy of three methods, which were principal components analysis, linear discriminant analysis and non-linear discriminant analysis, was obtained and compared. The correlations between bilateral hippocampal texture parameters and Mini-Mental State Examination (MMSE) scores were calculated. The classification accuracy of nonlinear discriminant analysis with a neural network model was the highest, and the classification accuracy of right hippocampus was higher than that of the left. The bilateral hippocampal texture features were correlated to MMSE scores, and the relative of right hippocampus was higher than that of the left. The neural network model with three-dimensional texture features could recognize AD patients and NC, and right hippocampus might be more helpful to AD diagnosis.
ObjectiveThe research goal: to study the diagnostic value of T2-flair sequence of magnetic resonance imaging (MRI) in hippocampal sclerosis. MethodsThe clinical data of 135 patients with epilepsy caused by hippocampal sclerosis in the Epilepsy Center of Tianshui Third People's Hospital from March 2019 to December 2020 were analyzed retrospectively, studying the correlation between the changes of hippocampal sclerosis signal and the frequency of epileptic seizures in MRI T2-flair sequence multi axial scanning. ResultsThere were 109 cases of simple hippocampal sclerosis and 26 cases of hippocampal sclerosis with other lesions, including 8 cases of cavernous hemangioma, 9 cases of traumatic or infectious malacia, 2 cases of focal cortical dysplasia, 1 case of cerebral fissure malformation, 1 case of giant gyrus and 5 cases of perinatal brain injury. MRI features of hippocampal sclerosis were as follows: ① hippocampal volume increased slightly, structure blurred, and T2-flair showed slightly increased hippocampal signal in 15 cases, accounting for 11.11%; ② The hippocampal formation was fuzzy, T2-flair was punctate hyperintense, and the volume did not change in 17 cases (12.59%); ③ Hippocampal pyknosis into small lumps, T2-flair sequence showed high signal in 103 cases, accounting for 76.30%. Statistics showed that there was a correlation between hippocampal sclerosis signal and seizure frequency (χ2=94.94, P<0.05). The higher the hippocampal sclerosis signal, the more the seizure frequency. ConclusionMRI T2-flair sequence multi axial scanning can improve the diagnostic accuracy of hippocampal sclerosis. As the change of hippocampal sclerosis signal becomes more obvious, the trend of seizure frequency increases.
Epilepsy is a heterogeneous disease with a very complex etiological mechanism, characterized by recurrent and unpredictable abnormal neuronal discharge. Epilepsy patients mainly rely on oral antiseizure medication (ASMs) the for treatment and control of disease progression. However, about 30% patients are resistance to ASMs, leading to the inability to alleviate and cure seizures, which gradually evolve into refractory epilepsy. The most common type of intractable epilepsy is temporal lobe epilepsy. Therefore, in-depth exploration of the causes and molecular mechanisms of seizures is the key to find new methods for treating refractory epilepsy. Mitochondria are important organelles within cells, providing abundant energy to neurons and continuously driving their activity. Neurons rely on mitochondria for complex neurotransmitter transmission, synaptic plasticity processes, and the establishment of membrane excitability. The process by which the autophagy system degrades and metabolizes damaged mitochondria through lysosomes is called mitophagy. Mitophagy is a specific autophagic pathway that maintains cellular structure and function. Mitochondrial dysfunction can produce harmful reactive oxygen species, damage cell proteins and DNA, or trigger programmed cell death. Mitophagy helps maintain mitochondrial quality control and quantity regulation in various cell types, and is closely related to the occurrence and development of epilepsy. The imbalance of mitophagy regulation is one of the causes of abnormal neuronal discharge and epileptic seizures. Understanding its related mechanisms is crucial for the treatment and control of the progression of epilepsy in patients.
ObjectiveTo investigate the status and prognosis effect of surgical operation for Temporal lobe epilepsy.MethodsRetrospective analyses were performed on 24 patients with intractable temporal lobe epilepsy who were treated by surgery in Zibo Changguo Hospital and had complete clinical and follow-up data, during the period from April 2011 to June 2014. Among them, 14 were male and 10 were female, 16 to 44 years old, the average age was (24.40±6.26) years old, and the average course of disease was (12.50±8.42) years old. The clinical characteristics and prognosis of the patients were analyzed.ResultsAll 24 patients had hippocampal sclerosis and underwent "anterior temporal lobe and medial temporal structural resection". Patients were followed up for 5~7 years, the postoperative epileptic seizure of the patient reached grade Engel Ⅰ in 20 cases (83.3%), grade Engel Ⅱ in 2 cases (8.3%) and grade Engel Ⅳ in 2 cases (8.3%).ConclusionHippocampal sclerosis and cortical dysplasia were common in 24 patients, and the operation controlling intractable epilepsy was better. In order to improve the prognosis of patients, surgical treatment should be carried out as soon as possible.
ObjectiveTo investigate the effects of hippocampal long-term potentiation (LTP) on cognitive dysfunction in immature epileptic rats. MethodsImmature epileptic rats were established by intraperitoneal injection of lithium chloride-pilocarpine (li-pilo). Racine classification standard modified by Becker was used to evaluate behavior of epileptic seizure, and the survival rats within RacineⅣmagnitude were selected in the experiment. The function of learning and memory of epileptic rats when they were adult was assessed using Morris water maze experiment, and their independent exploratory behavior was evaluated by the open-field test. Field potential was recorded by electrophysiological technology to detecte whether hippocampal LTP was essential of cognitive dysfunction. ResultsThe function of learning and memory was significantly impaired when compared with controls(n=8, t=10.86, P < 0.05;n=8, t=9.98, P < 0.05). In addition, independent exploratory behavior was significantly reduced when compared with controls(n=8, t=12.89, P < 0.05). Besides, CA1 hippocampal LTP induced by high-frequency stimulation presented the significant inhibition in epileptic rats with cognitive dysfunction when compared with controls(Slope:n=8, t=13.32, P < 0.05;Amplitude:n=8, t=20.02, P < 0.05). ConclusionInhibition of CA1 hippocampal LTP may be implicated in cognitive dysfunction of epileptic rats.
ObjectiveTo preliminary study on the feasibility of constructing three-dimensional (3D) hippocampal neural network in vitro by using microfluidic technology.MethodsA network patterned microfluidic chip was designed and fabricated by standard wet etching process. The primary hippocampal neurons of neonatal Sprague Dawley rats were isolated and cultured, and then inoculated on microfluidic chip for culture. Immunofluorescence staining was used to observe the growth of hippocampal neurons at 3, 5, and 7 days of culture and electrophysiological detection of hippocampal neuron network at 7 days of culture.ResultsThe results showed that the number of hippocampal neurons increased gradually with the prolongation of culture time, and the neurite of neurons increased accordingly, and distributed uniformly and regularly in microfluidic chip channels, suggesting that the 3D hippocampal neuron network was successfully constructed in vitro. Single and multi-channel spontaneous firing signals of hippocampal neuronal networks could be detected at 7 days of culture, suggesting that neuronal networks had preliminary biological functions.ConclusionPatterned microfluidic chips can make hippocampal neurons grow along limited paths and form 3D neuron networks with corresponding biological functions such as signal transduction, which lays a foundation for further exploring the function of neuron networks in vitro.
目的 研究利多卡因对海马的神经毒性是否会对大鼠空间学习记忆能力产生影响，并探讨大鼠空间学习能力的变化与海马CA3区锥体细胞数目的相关性。 方法 将成年Wistar雄性大鼠随机分为基础值组（n=7）和利多卡因惊厥组（n=40）。基础值组大鼠静脉给予生理盐水后使用Y迷宫测定大鼠的空间学习能力。利多卡因惊厥组大鼠尾静脉持续输注利多卡因造成惊厥，待大鼠恢复正常运动以后放入鼠笼重新饲养。并于惊厥后第1、3、5、7天从中随机抓取大鼠测试其空间学习能力以及组织学改变。根据对应天数将利多卡因惊厥组的40只大鼠随机细分为Day-1、Day-3、Day-5、Day-7亚组，每亚组10只。所有大鼠在测定空间学习能力之后立即处死，取出大脑并做石蜡包埋，冠状面切片后进行组织学检测，显微镜下评估海马CA3区锥体细胞状态。 结果 ① 基础值组和Day-1、Day-3、Day-5、Day-7亚组大鼠的Y迷宫穿梭次数分别为（25.2 ± 3.7）、（27.1 ± 8.1）、（36.9 ± 9.9）、（38.7 ± 10.6）、（40.6 ± 16.3）次，除Day-1亚组与基础值组比较差异无统计学意义（P＞0.05）外，其余各亚组与基础值组差异均有统计学意义（P＜0.05）；② 与基础值组单位面积（10.3 ± 4.5）个（异常锥体）细胞比较，利多卡因惊厥组大鼠海马CA3区异常锥体细胞数增加，Day-1、Day-3、Day-5、Day-7亚组计数值分别为13.0 ± 7.2、15.6 ± 5.0、19.6 ± 8.1、18.1 ± 5.1，且与大鼠Y迷宫穿梭次数呈正相关（r=0.711，P＜0.05）。 结论 利多卡因引起的惊厥使成年大鼠海马依赖性空间学习能力下降，利多卡因的神经毒性引起的海马异常锥体细胞增多可能是造成这一现象的一种原因。