摘要
Objective:To explore the clinical application of portable head and neck magnetic resonance imaging (MRI) device in neurosurgery.Methods:A total of 213 patients with brain diseases who were scanned by portable head and neck MRI device in Center of Neurosurgery, Zhujiang Hospital, Southern Medical University from June to September 2022 were selected. The portable head and neck MRI images and 3.0T conventional MRI images of 10 randomly selected patients were compared; the differences in signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of different sequences were analyzed. Thirty-one patients accepted tracheal intubation/tracheotomy, or ventilator-assisted breathing were selected as special patient group, and another 30 patients were as general patient group; the differences in comprehensive diagnostic scores of portable head and neck MRI images were compared. Noise intensity differences in different sequences between 3.0T conventional MRI and portable head and neck MRI were statistically compared. Twenty hospitalized volunteers with normal hearing in our center from July to August 2022 were selected, conventional 3.0T MRI and portable head and neck MRI were performed successively, and the noise intensity of different sequences in them was evaluated by using a 5-point system.Results:Compared with those in 3.0T conventional MRI images, the SNR and CNR of T1WI, T2WI, and Liquid attenuated reverse recovery sequence (FLAIR) sequences in portable head and neck MRI images were significantly lower ( P<0.05). No significant difference was noted in the comprehensive diagnostic scores of portable head and neck MRI images between special patients and general patients ( P>0.05). Compared with that in the 3.0T conventional MRI, the noise intensity of different sequences in portable head and neck MRI was significantly reduced ( P<0.05). These volunteers had significantly reduced noise intensity scores of different sequences in portable head and neck MRI compared with that in conventional 3.0T MRI ( P<0.05). Conclusion:Portable head and neck MRI device is easy to use, enjoying high safety, imaging quality and suitability, which meets the clinical needs for neurosurgery patients.
摘要
Excessive theta (θ) frequency oscillation and synchronization in the basal ganglia (BG) has been reported in elderly parkinsonian patients and animal models of levodopa (L-dopa)-induced dyskinesia (LID), particularly the θ oscillation recorded during periods when L-dopa is withdrawn (the off L-dopa state). To gain insight into processes underlying this activity, we explored the relationship between primary motor cortex (M1) oscillatory activity and BG output in LID. We recorded local field potentials in the substantia nigra pars reticulata (SNr) and M1 of awake, inattentive resting rats before and after L-dopa priming in Sham control, Parkinson disease model, and LID model groups. We found that chronic L-dopa increased θ synchronization and information flow between the SNr and M1 in off L-dopa state LID rats, with a SNr-to-M1 flow directionality. Compared with the on state, θ oscillational activity (θ synchronization and information flow) during the off state were more closely associated with abnormal involuntary movements. Our findings indicate that θ oscillation in M1 may be consequent to abnormal synchronous discharges in the BG and support the notion that M1 θ oscillation may participate in the induction of dyskinesia.
摘要
Objective To investigate the mechanism of improvement of gait behavior in PD rat models by low frequency electrical stimulation of pedunculopontine tegmental nucleus (PPTN) by optogenetics method. Methods (1) Twenty-four healthy adult male SD rats were randomly divided into a sham-operated group 1, a lesion group 1 and a photoactivation group (n=8); normal saline was injected into the right medial frontal tract (MFB) of the sham-operated group 1; 6-hydroxydopamine (6-OHDA) was injected into the lesion group 1 and photoactivation group to induce PD models; two weeks after modeling, injection of adeno-associated virus hsynapsin-ChR2-mcherry into the right PPTN of the three groups was performed, and the photoactivation group received blue-ray stimulation by implanting optical fibers into the PPTN at the same time. (2) Twenty-four healthy adult male SD rats were randomly divided into a sham-operated group 2, a lesion group 2 and a photoinhibition group (n=8);normal saline was injected into right MFB of the sham-operated group 2; 6-OHDA was injected into the lesion group 2 and photoinhibition group to induce PD models; two weeks after modeling, injection of adeno-associated virus hsynapsin-NpHR-mcherry into the right PPTN of the three groups was performed, and the photoinhibition group received yellow-ray stimulation by implanting optical fibers into the PPTN at the same time. (3) Three weeks after injection of adeno-associated virus, Catwalk gait analysis was used to assess the behavioral ability of rats in each group. Results (1) As compared with the sham-operated group 1, lesion group 1 had significantly increased front claw spacing and back front claw spacing, and significantly decreased stride length and pressure of damaged lateral and contralateral limbs, and significantly decreased swing speed of contralateral limb (P<0.05); as compared with those in the lesion group 1, the front claw spacing and back claw spacing were significantly shortened, and stride length and pressure of damaged lateral and contralateral limbs were statistically increased in the photoactivation group (P<0.05). (2) As compared with the sham-operated group 2, lesion group 2 had significantly increased front claw spacing and back front claw spacing, significantly decreased stride length of damaged lateral limb, and significantly decreased pressure and swing speed of damaged lateral and contralateral limbs (P<0.05); no significant differences were noted on the front claw spacing and back front claw spacing, pressure and swing speed of damaged lateral and contralateral limbs between lesion group 2 and photoinhibition group (P>0.05). Conclusion The mechanism of low frequency electrical stimulation of PPTN improving gait behavior of PD rat models is related to activation of PPTN neurons.
摘要
Deep brain stimulation (DBS) has been widely used in the treatment of a variety of functional neurological diseases.The high-frequency electrical stimulation of subthalamic nucleus can improve tremor,bradykinesia,and rigidity of patients with Parkinson's disease,however,the effects of DBS on gait and balance disorders don't get very good improvement.Recently,clinical studies have found that low frequency pedunculopontine nucleus stimulation can relieve these axial symptoms.Hence we will summarize the clinical researches on the low-frequency deep brain stimulation of pedunculopontine nucleus.
摘要
OBJECTIVE: The aim of this study was to investigate voluntary wheel running behavior in the unilateral 6-hydroxydopamine (6-OHDA) rat model. METHODS: Male Sprague-Dawley rats were assigned to 2 groups : 6-OHDA group (n=17) and control group (n=8). The unilateral 6-OHDA rat model was induced by injection of 6-OHDA into unilateral medial forebrain bundle using a stereotaxic instrument. Voluntary wheel running activity was assessed per day in successfully lesioned rats (n=10) and control rats. Each behavioral test lasted an hour. The following parameters were investigated during behavioral tests : the number of running bouts, the distance moved in the wheel, average peak speed in running bouts and average duration from the running start to the peak speed. RESULTS: The number of running bouts and the distance moved in the wheel were significantly decreased in successfully lesioned rats compared with control rats. In addition, average peak speed in running bouts was decreased, and average duration from the running start to the peak speed was increased in lesioned animals, which might indicate motor deficits in these rats. These behavioral changes were still observed 42 days after lesion. CONCLUSION: Voluntary wheel running behavior is impaired in the unilateral 6-OHDA rat model and may represent a useful tool to quantify motor deficits in this model.
Subject(s)
Animals , Humans , Male , Rats , Medial Forebrain Bundle , Models, Animal , Oxidopamine , Parkinson Disease , Rats, Sprague-Dawley , Running摘要
Objective To study the effect of low frequency stimulation (LFS) in the pedunculopontine tegmental nucleus (PPTg) on gait and movement ability in unilateral lesioned Parkinson's disease(PD) rats.Methods Thirty-two male SD rats were randomly assigned to control group (6-hydroxydopamine treatment,n=8) and experimental group (6-hydroxydopamine treatment combined with electrode implantation,n=24).All subjects were processed with injection of 6-hydroxydopamine in the fight medial forebrain bundle (MFB) and simultaneously the rats in the experimental group were received an electrode implantation into the ipsilateral PPTg.Catwalk gait and open field test data were acquired at 1 week before stereotactic surgery and 3 weeks after operation in the rats of control and experimental groups; the behavioral data of rats in the experimental group were recorded again 4 weeks after operation when they were under ongoing LFS-PPTg.Results Catwalk results showed that the postoperative couplings values (right front→left front,right front→left hind,right hind →left front,right hind →left hind) were significantly increased in all subjects as compared with the preoperative ones (P＜0.05); while couplings value in rats of the experimental group after LFS-PPTg significantly reduced as compared with that before LFS-PPTg (P＜0.05).The postoperative run speed variation statistically increased and postoperative cadence significantly decreased in all rats as compared with the preoperative ones (P＜0.05); the run speed variation significantly decreased and cadence obviously increased in experimental group after LFS-PPTg as compared with those before LFS-PPTg (P＜0.05).Open field test:the moving distance of all subjects decreased significantly after operation; the distance in rats of the experimental group after LFS-PPTg increased significantly as compared with that before LFS-PPTg.Conclusion LFS-PPTg can effectively improve gait function and motor activity of unilateral PD rat models.
摘要
OBJECTIVE: A series of recent studies have demonstrated the mechanism of migration and nerve net of neural stem cells. These theories have further substantiated neural stem cell transplantation. In view of these new findings, this paper reviewed the mode of migration and information of network. The significance of these theories was discussed.DATA SOURCE: We search on Pubmed with the key words "neural stem cell", "migration", and "nerve net", limiting the language to English and publication date from 1970 to 2004. At the same time we searched on CNKI.STUDY SELECTION: We selected the randomized and non-randomized controlled studies related to migration and nerve net building of neural stem cells. Review articles and articles with repetitive studies were excluded.DATA EXTRACTION: Among 39 papers selected, 16 papers concerning the development of this topic were selected, and the others were excluded.DATA SYNTHESIS: For retrograde lesions and severe injury of nervous system, transplantation of nerve stem cells may replace aging degenerative and dead nerve cells and rebuild neural network for the recovery of cerebral function. Migration of nerve cell and network principle can solve the survival, differentiation, migration and creation of nerve network after transplantation of nerve stem cells so as to realize the recovery and reconstruction of cerebral function.CONCLUSION: Neural stem cells can migrate to intended places and can build nerve net under some conditions, which will be useful for medicine deyelopment.
摘要
To explore the role and changes of dopamine receptor activity and their subtypes during the onset process of Parkinson disease( PD ), on the basis of 6 hydroxydopamine lesioned PD rat model, radioligand binding assay (RLBA) and Scanchard drawing were used to measure the maximal binding capacity of receptor (Bmax) and equilibrium dissociation constant (KD) of D 1 and D 2 dopamine receptors in caudal putamen of the model and control rats at different time point. The results of RLBA study revealed D 2 dopamine receptor Bmax was significantly increased and KD was significantly decreased in the caudal putamen ipsilateral to the lesion in rat model, and the changes reached the peak in one month rat model group. In contrast, the caudal putamen D 1 receptors were far less affected, with no consistent changes in the same model groups as compared with the control, except that 2 weeks model group showed Bmax was slightly decreased while KD was slightly increased. The study confirms that D 2 dopamine receptor is upregulated in the caudal putamen ipsilateral to the lesion in PD rat model, and the affinity of the receptors is increased, but the activity of D 1 dopamine receptor is not significantly changed.