Traumatic brain injury (TBI) is associated with poor neurological outcome, including necrosis and brain edema. In this study, we investigated whether agmatine treatment reduces edema and apoptotic cell death after TBI. TBI was produced by cold injury to the cerebral primary motor cortex of rats. Agmatine was administered 30 min after injury and once daily until the end of the experiment. Animals were sacrificed for analysis at 1, 2, or 7 days after the injury. Various neurological analyses were performed to investigate disruption of the blood-brain barrier (BBB) and neurological dysfunction after TBI. To examine the extent of brain edema after TBI, the expression of aquaporins (AQPs), phosphorylation of mitogen-activated protein kinases (MAPKs), and nuclear translocation of nuclear factor-kappaB (NF-kappaB) were investigated. Our findings demonstrated that agmatine treatment significantly reduces brain edema after TBI by suppressing the expression of AQP1, 4, and 9. In addition, agmatine treatment significantly reduced apoptotic cell death by suppressing the phosphorylation of MAPKs and by increasing the nuclear translocation of NF-kappaB after TBI. These results suggest that agmatine treatment may have therapeutic potential for brain edema and neural cell death in various central nervous system diseases.
Active Transport, Cell Nucleus/drug effects ; Agmatine/*therapeutic use ; Animals ; Apoptosis/*drug effects ; Aquaporins/metabolism ; Blood-Brain Barrier/physiopathology ; Brain Edema/*drug therapy ; Brain Injuries/*pathology ; Male ; Mitogen-Activated Protein Kinases/metabolism ; Motor Cortex/*pathology ; NF-kappa B/metabolism ; Phosphorylation/drug effects ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To find an objective and accurate examination for evaluation of spinal cord injury (SCI) in forensic clinical medicine. METHODS: The onset latency of cortex, peak latency of N1, central motor conduction time (CMCT) and wave width of the abductor pollicis brevis and the anterior tibialis were calculated by transcranial magnetic stimulation-motor evoked potential (TMS-MEP). The data of 68 patients suffered from SCI including 23 cervical levels and 45 thoracolumbar levels were collected and compared with that of 30 normal controls. RESULTS: In experimental group, when the muscle strength of the abductor pollicis brevis or the anterior tibialis decreased or disappeared, the onset latency of cortex, the peak latency of N1, and CMCT prolonged and the wave width broadened. And these indexes of grade 2 and 3 muscle strength in experimental group were higher than that in the control group (P < 0.05). CONCLUSION The TMS-MEP can determine directly and objectively the motor functional status of pyramidal tract of spinal cord in order to provide more accurate and objective evidences in forensic medicine.
Adolescent ; Adult ; Case-Control Studies ; Evoked Potentials, Motor/physiology* ; Female ; Forensic Medicine/methods* ; Humans ; Male ; Middle Aged ; Monitoring, Physiologic ; Motor Cortex/physiology* ; Muscle, Skeletal/physiology* ; Neural Conduction/physiology* ; Reaction Time/physiology* ; Spinal Cord Injuries/physiopathology* ; Transcranial Magnetic Stimulation ; Young Adult

Transcranial magnetic stimulation-motor evoked potential (TMS-MEP) test is one of the electrophysiological examination methods to evaluate the function of central nervous system. The value of the TMS-MEP has been recognized by some clinical forensic workers recently. This article reviews the principle and advantages of TMS-MEP and its application in functional evaluation of central nervous system and clinical treatment. The value of TMS-MEP in forensic medicine, especially in objective assessment of muscle strength after injury of central nervous system is also discussed.
Central Nervous System Diseases/physiopathology* ; Disability Evaluation ; Evoked Potentials, Motor/physiology* ; Forensic Medicine/methods* ; Humans ; Monitoring, Physiologic/methods* ; Motor Cortex/physiopathology* ; Muscle, Skeletal/physiopathology* ; Neural Conduction/physiology* ; Predictive Value of Tests ; Severity of Illness Index ; Spinal Cord Injuries/physiopathology* ; Transcranial Magnetic Stimulation

Transcranial direct current stimulation (tDCS) is associated with enhancement or weakening of the NMDA receptor activity and change of the cortical blood flow. Therefore, repeated tDCS of the brain with cerebrovascular injury will induce the functional and histologic changes. Sixty-one Sprague-Dawley rats with cerebrovascular injury were used. Twenty rats died during the experimental course. The 41 rats that survived were allocated to the exercise group, the anodal stimulation group, the cathodal stimulation group, or the control group according to the initial motor function. Two-week treatment schedules started from 2 days postoperatively. Garcia, modified foot fault, and rota-rod performance scores were checked at 2, 9, and 16 days postoperatively. After the experiments, rats were sacrificed for the evaluation of histologic changes (changes of the white matter axon and infarct volume). The anodal stimulation and exercise groups showed improvement of Garcia's and modified foot fault scores at 16 days postoperatively. No significant change of the infarct volume happened after exercise and tDCS. Neuronal axons at the internal capsule of infarct hemispheres showed better preserved axons in the anodal stimulation group. From these results, repeated tDCS might have a neuroprotective effect on neuronal axons in rat stroke model.
Animals ; Axons/pathology ; Cerebral Cortex/physiology ; Disease Models, Animal ; Electric Stimulation ; Motor Activity/physiology ; Rats ; Rats, Sprague-Dawley ; Stroke/metabolism/*pathology/physiopathology

OBJECTIVETo explore the function and motor pathway of remained cerebral hemisphere by studying motor evoked potential of both upper extremities on patients long term after anatomical hemispherectomy.

METHODSFive patients after anatomical hemispherectomy, who were marked 5 dispersive sites on head to perform transcranial magnetic stimulation. Recording motor evoked potential of target muscles (brachioradialis muscle and abductor pollicis brevis) of both upper extremities respectively when muscle resting and contracting.

RESULTSOnly affected abductor pollicis brevis of case 2 and only affected brachioradialis muscle of case 4 and 5 recorded motor evoked potential when muscle resting. Motor evoked potential of some cases can be recorded simultaneously in homonymous muscles of both sides when muscle resting or contracting.

CONCLUSIONSThere exists motor cortex that controls movement of ipsilateral limbs and also ipsilateral motor pathway of corticospinal connection at patients after anatomical hemispherectomy. It also means that the motor function of affected limbs has potency to recover well after hemispherectomy. The mirror movement after hemispherectomy is possible relate to overlap of both limbs' motor cortex.

Adult ; Evoked Potentials, Motor ; physiology ; Female ; Follow-Up Studies ; Hemispherectomy ; Humans ; Male ; Motor Cortex ; physiopathology ; Postoperative Period ; Transcranial Magnetic Stimulation ; Upper Extremity ; physiopathology

OBJECTIVE: To explore the geomorphological performance, the characteristics of volume, and the largest signal intension of blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) in brain tumors located in or closed to the central area. METHODS: We recruited 13 normal volunteers and 31(13 benign tumors and 18 malignant tumors) patients with brain tumor located in or closed to the central area, to examine both side hand motor and tactile function by BOLD-fMRI and obtained the activation map and its superposition image with T1 imaging, the volume, and the largest signal intension of the functional area by SPM software which manipulated the raw data in the off-line work station. The volume and the largest signal intension data of the functional area were statistically analyzed by SPSS 13.0. RESULTS: The volume and the largest signal intension of the activation map in the normal functional area had hemisphere advantage. There was difference in the activated signal pixel number and the largest signal intension of the functional area between the benign brain tumors, malignant brain tumors, and the normal volunteers (P < 0.05). The shape, anatomic location, the volume, and the largest signal intension of the functional area were changed in the patients with brain tumors. CONCLUSION BOLD-fMRI is a valid method to assess the pre-surgical risk of patients with brain tumors, which can get the volume, the largest signal intension, the basic shape,and the anatomic location of the functional area.
Adolescent ; Adult ; Aged ; Brain Neoplasms ; blood ; physiopathology ; Female ; Hand ; physiopathology ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Motor Cortex ; pathology ; physiopathology ; Oxygen ; blood ; Somatosensory Cortex ; pathology ; physiopathology

Tremor, a rhythmic and involuntary oscillatory movement of one or several body parts, is the movement resulting from the abnormal synchronization of motor neural units. Detecting and analyzing the ACC, EMG and EEG signals of tremor patients by signal processing methods are very important for clinical diagnosis, rating evaluation and detection of incipient illness. This paper introduces the applications of time domain,frequency domain, artificial neural network, high order accumulation, approximate entropy, fuzzy, chaos, discriminant analysis in the researches of tremor signals, and finally points out the application foreground of researches on tremor signals.
Electroencephalography ; methods ; Electromyography ; methods ; Humans ; Motor Cortex ; physiopathology ; Muscle, Skeletal ; physiopathology ; Signal Processing, Computer-Assisted ; Tremor ; physiopathology

OBJECTIVETo evaluate the nitric oxide (NO) levels in rat brain cortex and hippocampus after chronic mild stress.

METHODSSixteen male Sprague-Dawley rats were allocated into control group and model group randomly. Model rats were induced by consecutive chronic mild stress; weight gain, open field test and sucrose solution consumption were investigated before and after procedure. Nitric oxide contents in prefrontal cortex and hippocampus were determined by spectrophotometric assays.

RESULTDecreased locomotion, loss of interest and anhedonia were observed in chronic mild stress rat model group. Nitric oxide contents in prefrontal cortex and hippocampus were significantly higher in chronic mild stress group [(31.00 +/-2.55)nmol/mg.pro and (38.11 +/-1.73)nmol/mg.pro, respectively] than those in control group [(26.97 +/-1.38)nmol/mg.pro and (36.06 +/-0.87)nmol/mg.pro, respectively] (P <0.05).

CONCLUSIONChronic stress can stimulate NO release, and dysfunction of nitric oxide pathway may be involved in development of depression.

Animals ; Cerebral Cortex ; metabolism ; Depression ; etiology ; physiopathology ; Hippocampus ; metabolism ; Male ; Motor Activity ; physiology ; Nitric Oxide ; biosynthesis ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Stress, Psychological ; complications ; physiopathology

This study is to observe the effect of salvianolic acid B (Sal B) on neural cells damage and neurogenesis in sub-granular zone (SGZ) and sub-ventricular zone (SVZ) after brain ischemia-reperfusion (I/R) in rats. A modified middle cerebral artery occlusion (MCAO) model of focal cerebral ischemia-reperfusion was used. The rats were divided into four groups: sham control group, ischemia-reperfusion group, Sal B 1 and 10 mg x kg(-1) groups. Sal B was consecutively administrated once a day by ip injection after MCAO. The neurogenesis in SGZ and SVZ was investigated by BrdU method 7 days after MCAO. The Nissl staining for neurons in the hippocampal CA1 and cerebral cortex was performed 14 days after MCAO. A beam-walking test was used to monitor the motor function recovery. We found that brain ischemia resulted in an increase of BrdU positive cells both in ipsilateral SGZ and SVZ at 7th day after MCAO. Sal B (10 mg x kg(-1)) significantly increased further the number of BrdU positive cells both in SGZ and SVZ (P < 0.01). Ipsilateral hippocampal neuron damage occurred and CA1 almost lost 14 days after MCAO. Sal B (10 mg x kg(-1)) obviously attenuated the neuron damage and increased the number of neuron both in ipsilateral CA1 and cerebral cortex (P < 0.01). We also observed an obvious improvement of motor function recovery when Sal B (10 mg x kg(-1)) administrated. From the results above we concluded that Sal B stimulated neurogenesis process both in SGZ and SVZ after brain ischemia, and also alleviated neural cells loss and improved motor function recovery after brain ischemia in rats.
Animals ; Benzofurans ; isolation & purification ; pharmacology ; Cell Count ; Cerebral Cortex ; pathology ; Cerebral Ventricles ; pathology ; Dentate Gyrus ; pathology ; Hippocampus ; pathology ; Infarction, Middle Cerebral Artery ; complications ; Male ; Motor Activity ; drug effects ; Neurogenesis ; drug effects ; Neurons ; drug effects ; pathology ; Plants, Medicinal ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; etiology ; pathology ; physiopathology ; Salvia miltiorrhiza ; chemistry

OBJECTIVEOur previous work suggested that sensitivity of hippocampal neurons is changed in process of epileptic activities, and closely parallel to the dynamic characteristic of epileptic activity of the neurons. This study investigated the sensitivity of epileptic brain to vagal nerve stimulation (VNS) in epileptic process.

METHODSEpileptic model was evoked by penicillin. Left vagal nerves were stimulated to inhibit the seizures induced by penicillin. The electrocorticography (ECoG) and electromyography (EMG) were recorded to analyze inhibiting effect of VNS in epileptic process.

RESULTSIt was found that VNS could inhibit the seizures caused by penicillin, and the inhibiting effect of VNS to seizures increased as the vagal nerve stimulating time prolonged. It was also found that the inhibiting effect of VNS to seizures decreased in epileptic process.

CONCLUSIONThe results suggested that the sensitivity of epileptic brain to VNS was different in epileptic process. The inhibiting effect of VNS to seizure decreased as the development of seizures.

Action Potentials ; physiology ; Animals ; Electric Stimulation ; Electroencephalography ; Electromyography ; Epilepsy ; chemically induced ; prevention & control ; Frontal Lobe ; physiopathology ; Male ; Motor Cortex ; drug effects ; physiopathology ; Neural Inhibition ; physiology ; Nonlinear Dynamics ; Parietal Lobe ; physiopathology ; Penicillins ; Rats ; Rats, Sprague-Dawley ; Seizures ; chemically induced ; prevention & control ; Vagus Nerve ; physiology