Due to its great clinical significance, brain injury following cardiac arrest (CA) has attracted more attention now. Meanwhile, there are currently no approved real time objective methods used to monitor brain injury following CA. In this study, we adopt the method of nonextensive Kullback-Leibler Entropy in investigating the HRV signals from brain injury and compare the result with that of corresponding EEG analysis. The comparative analysis shows that Kullback-Leibler Entropy can reveal the injury level of brain following CA. And we propose a novel quantitative approach for monitoring brain injury.
Algorithms ; Brain ; pathology ; physiopathology ; Brain Ischemia ; physiopathology ; Electroencephalography ; Heart Arrest ; complications ; Heart Rate ; physiology ; Humans

Burns ; complications ; pathology ; physiopathology ; Humans ; Mitochondria, Heart ; pathology ; Myocardial Ischemia ; etiology ; prevention & control

The present study was designed to observe the influence of cerebral ischemia/reperfusion injury on learning and memory in hyperlipidemic rats and estimate the changes of activity of autonomic nervous system. Twenty-three male Wistar rats were randomly divided into three groups, named control group (C group, n=10), hyperlipidemia group (H group, n=6) and hyperlipidemia-ischemia group (HI group, n=7), respectively. The rats in H and HI group were fed a high-fat diet for 2 weeks and the rats in all groups were examined through Morris water maze (MWM) task. The rats in HI group underwent ischemia/reperfusion by 2-vessel occlusion (2-VO) method, and had electrocardiogram (ECG) recording simultaneously. The MWM task and ECG recording were taken again after 7 d of recuperation. The following results were obtained: (1) In the second place navigation performance and probe trial performance, the frequency of memory in quadrant of hidden-platform and memory score decreased significantly in HI group compared to that in C and H groups. (2) The heart rate in HI group decreased slowly after ischemia; the power at high frequency band (HF) reduced gradually, meanwhile the power at middle frequency band (MF) and the ratio of power at MF and HF decreased clearly compared to baseline value. (3) After 7 d of ischemia/reperfusion, the heart rate in HI group was significantly higher than that in H group (P<0.05). While there was no statistical change in the power at MF, the power at HF decreased and the ratio of MF/HF increased significantly (P<0.05). The data demonstrated that ischemia/reperfusion decreased the activity of autonomic nervous system, and the reduction of sympathetic nerve activity was much more than that of vagus nerve activity. The results suggest that the hippocampus neuron injury caused by ischemia induces cognitive disorder and imbalance of vago-sympathetic nerve activity accompanied by vagus nerve suppression.
Animals ; Autonomic Nervous System ; physiopathology ; Brain Ischemia ; etiology ; physiopathology ; Heart Rate ; physiology ; Hippocampus ; physiopathology ; Hyperlipidemias ; complications ; Learning Disorders ; etiology ; physiopathology ; Male ; Memory Disorders ; etiology ; physiopathology ; Random Allocation ; Rats ; Rats, Wistar ; Reperfusion Injury ; pathology ; physiopathology

BACKGROUND/AIMS: Inflammation plays a key role in ischemic acute renal failure (ARF). The present study investigated the infiltration of macrophages in the early phase of ischemic ARF in mice. METHODS: Ischemic ARF was induced by renal clamping for 22 min, while the control mice underwent sham surgery (no clamping). The serum creatinine and blood urea nitrogen (BUN) levels were measured in the control and post-ischemia mice. Immunofluorescence staining was used to measure the number of CD 11b-positive cells in the kidney tissue sections to determine the amount of post-ischemic macrophage infiltration. Lipo-Cl2MBP (clodronate) for macrophages depletion was injected via a tail vein 5 d before ischemia induction and again 2 d before ischemia induction. RESULTS: The study found that the post-ischemia mice had higher levels of serum creatinine and BUN at 16 and 24 h compared to the controls. Immunofluorescence staining showed there were more macrophages in the post-ischemic tissue at 2, 8, 16 and 24 h compared to the control tissue, and that most of these macrophages were located in the outer medulla. The mice treated with clodronate prior to ischemia induction were found to have lower levels of serum creatinine compared to those mice that weren't treated with clodronate. CONCLUSIONS: There was significant infiltration of macrophages from the early phase of ischemic ARF, and this peaked at 16-24 h. Macrophage depletion using clodronate was protective against ischemic ARF.
Animals ; Antigens, CD11b ; Blood Urea Nitrogen ; Clodronic Acid ; Creatinine/blood ; Fluorescent Antibody Technique ; Inflammation/*physiopathology ; Ischemia/*complications/pathology/physiopathology ; Kidney Failure, Acute/blood/etiology/*pathology/physiopathology ; Kidney Medulla/*pathology ; *Macrophages ; Male ; Mice ; Mice, Inbred C57BL ; Perfusion ; Time Factors

PURPOSE: The purpose of this study was to examine the effects of cerebral ischemia on Type I(soleus) and Type II(plantaris, gastrocnemius) muscles, and to determine the effects of isometric contraction training by electrostimulation on Type I andII muscles in cerebral ischemia model rats. METHOD: Twenty-five male Sprague-Dawley rats were randomly divided into four groups: ST(stroke), STES(stroke+electrostimulation), SH(sham) and SHES (sham+electrostimulation). The ST and STES groups received a transient right middle cerebral artery occlusion operation. The SH and SHES groups received a sham operation. The STES and SHES groups had daily isometric contraction training by electrostimulation(100Hz, 45mA, 7.5V) on hindlimb muscles for 7days. RESULT: Plantaris and gastrocenmius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the muscle fiber cross-sectional area of gastrocnemius in the ST group significantly decreased compared with the SH group. Soleus, plantaris, gastrocnemius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the Type I muscle fiber cross-sectional area of soleus and the Type II muscle fiber cross-sectional area of gastrocnemius in the STES group significantly increased compared with the ST group. CONCLUSION: Hindlimb muscle atrophy occurs after acute stroke and isometric contraction training by electrostimulation during early stages of a stroke attenuates muscle atrophy of Type I and Type II muscles.
Animals ; Body Weight ; Brain Ischemia/*complications ; Disease Models, Animal ; Electric Stimulation ; Hindlimb ; *Isometric Contraction ; Male ; Muscle Proteins/analysis ; Muscle, Skeletal/metabolism/pathology/*physiopathology ; Muscular Atrophy/*etiology/pathology/physiopathology ; Myofibrils/chemistry ; Rats ; Rats, Sprague-Dawley ; Stroke/*complications

We measured the ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) and ABI in 97 ischemic stroke patients and 93 control subjects to investigate the relationship between baPWV, ABI and risk factors of ischemic stroke. The stroke patients were grouped according to the results of MRA and Carotid artery color Doppler ultrasound. The correlation of baPWV and ABI to the arteriosclerosis was discussed. There was a significant difference in the patients with hypertension, diabetes mellitus, baPWV and ABI between ischemic stroke patients and control subjects. baPWV was the most sensitive risk factor for ischemic stroke. ABI and diabetes mellitus were the relatively sensitive risk factors for ischemic stroke. baPWV were found to have a positive correlation with common carotid arteriosclerosis (gamma=0.215, P=0.048), while ABI had a negative correlation with intracranial arteriosclerosis (gamma=-0.237, P<0.05). BaPWV and ABI may closely relate to severity of ischemic stroke. Simple measurements of baPWV and ABI in patients could be a useful tool for evaluating the risk of ischemic stroke.
Aged ; Ankle ; blood supply ; Ankle Brachial Index ; Arteriosclerosis ; physiopathology ; Blood Flow Velocity ; Brachial Artery ; physiopathology ; Brain ; blood supply ; pathology ; Brain Ischemia ; complications ; Carotid Arteries ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Pulsatile Flow ; Pulse ; Risk Factors ; Stroke ; diagnosis ; etiology ; physiopathology

OBJECTIVETo determine whether the skilled reaching test is an objective method for evaluating long-term neurological deficits after focal cerebral ischemia in mice.

METHODSIn a reaching box, mice were trained to reach food pellets with their left forelimb through a 0.5 cm slit for 3 weeks. Then focal cerebral ischemia was induced by occluding the right middle cerebral artery, and the percentage of success in obtaining food was observed for 4 weeks. In comparison, the neurological deficit score, the holding angle in an inclined board test, and right turns in a corner test were simultaneously performed. At the end of the experiments, brain infarcts and neuron densities were determined.

RESULTAfter focal cerebral ischemia, the percentage of success in the reaching test was reduced, the right turns in the corner test were increased, the neurological deficit score was increased, and the holding angle in the inclined board test was reduced as well. The holding angle recovered 5 d after ischemia, whereas other 3 indicators remained abnormal until 4 weeks. At the end of the experiments, the brain infarct volumes were increased, and the neuron densities in the cortex, hippocampal CA1 region and striatum were reduced in ischemic mice.

CONCLUSIONThe skill reaching test is an objective and stable method for evaluating long-term neurological deficits after focal cerebral ischemia in mice.

Animals ; Behavior, Animal ; physiology ; Brain ; pathology ; physiopathology ; Brain Ischemia ; complications ; physiopathology ; Cell Count ; Male ; Mice ; Mice, Inbred ICR ; Movement Disorders ; etiology ; physiopathology ; Neurologic Examination ; methods ; Neurons ; pathology ; Psychomotor Performance ; physiology

OBJECTIVETo investigate the effect of Buyang Huanwu Decoction (, BYHWD) on estradiol (E2) and estradiol receptor (ER) in serum and brain in ovariectomized rats after middle cerebral artery occlusion (MCAO).

METHODSAdult female rats were ovariectomized and focal cerebral ischemic was induced by MCAO. Rats were randomly divided into normal, ovariectomy (OVX), MCAO, OVX+MCAO, OVX+MCAO+E2, and OVX+MCAO+BYHWD group. Rats were administered BYHWD 5 g/kg daily, estradiol valerate 500 μg/kg per day or distilled water for 7 consecutive days. Neuronal function and infarct volume were measured on day 7 after artery occlusion, and E2 and ER concentration in serum and brain were checked by enzyme-linked immunosorbent assay.

RESULTSBYHWD significantly improved the neurological behavior, reduced the infarction volume, increased E2 concentration in serum and brain, and increased ER concentration in the brain in ovariectomized rats after MCAO.

CONCLUSIONThe neuroprotective effects of BYHWD are associated with estrogen and its receptor.

Animals ; Brain ; drug effects ; metabolism ; pathology ; Brain Ischemia ; complications ; drug therapy ; pathology ; physiopathology ; Cerebral Infarction ; complications ; drug therapy ; pathology ; physiopathology ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Estradiol ; blood ; Female ; Infarction, Middle Cerebral Artery ; complications ; drug therapy ; pathology ; physiopathology ; Ovariectomy ; Rats, Wistar ; Receptors, Estradiol ; blood

AIMTo explore the effects of sleep deprivation (SD) on myocardium and its antioxygen index.

METHODS35 Sprague Dawley rats were randomly divided into five groups: Cage control, Tank control, SD 2 d, SD 4 d and SD 6 d. The "flower pot" technique was used to establish rats sleep deprivation model followed by record of surface electrocardiogram, detection of myocardium morphology changes under microscope and transmission electron microscope and investigation of MDA content and SOD activity of myocardial mitochondria.

RESULTSAfter sleep deprivation, heart rate increased and ECG showed ischemia of myocardium; subcellular organelles such as chromosome, endoplasmic reticulum, mitochondria, intercalated disk impaired, myofibril lysis or necrosis, and lipid peroxidation reaction effects spread widely; edema, bleeding of the microvessels and invasion of the monocytes could be seen in the lumen. The MDA level increased and SOD activity increased followed by a decreased trend.

CONCLUSIONSleep deprivation can induce damage on myocardium, and the stress especially oxygen stress caused by SD may be the possible mechanism.

Animals ; Electrocardiography ; Female ; Male ; Myocardial Ischemia ; etiology ; pathology ; physiopathology ; Oxidative Stress ; physiology ; Rats ; Rats, Sprague-Dawley ; Sleep Deprivation ; complications ; Superoxide Dismutase ; metabolism

OBJECTIVETo establish a general method of focal cerebral ischemia model in different varieties of mice.

METHODEach group of healthy adult KM and C57BL/6 mice were randomly divided into control group (n = 10) and MCAO group (n = 10). The mice in MCAO group were applied in the preparation of the MCAO model by intraluminal occlusion using monofilament. Twenty-four hours after operation,the neurologic function was evaluated,middle cerebral artery blood flow was monitored and the infarction volume was calculated by TTC staining, to evaluate the reliability of the model.

RESULTIn the MCAO group, the base value of the cerebral blood flow down of KM and C57BL/6 mice respectively was (81.65 ± 4.59)%, (83.68 ± 6.25)%. The neurological deficit score respectively was (2.30 ± 0.82), (2.50 ± 0.80). TTC staining can clearly show the infarction area, and relatively stable, 24 hours of the survival rate of KM and C57BL/6 mice were 100% and 80% respectively.

CONCLUSIONThe key link is the optimization and improvement of monofilament, temperature, anesthesia and so on. The modified intraluminal occlusion of MCAO using monofilament is a kind of reliable and simple method to establish experimental cerebral ischemia model in mice.

Animals ; Blood Flow Velocity ; Brain ; blood supply ; pathology ; physiopathology ; Brain Ischemia ; complications ; physiopathology ; Cerebrovascular Circulation ; Disease Models, Animal ; Infarction, Middle Cerebral Artery ; complications ; physiopathology ; Male ; Mice, Inbred C57BL ; Middle Cerebral Artery ; pathology ; physiopathology ; surgery ; Nervous System Diseases ; etiology ; physiopathology ; Species Specificity