Animals ; Basilar Artery ; Brain Ischemia ; pathology ; Brain Stem ; blood supply ; Cats ; Medulla Oblongata ; blood supply

The purpose of this study was to establish a method to record the dynamic process of vascular regeneration and remodeling in rat cerebral ischemic regions. An animal brain window model was established to continuously observe the changes of rat cortical vascular ischemia in vivo, and the model of cerebral ischemia was established by photochemical embolization. Optical coherence tomography (OCT) was performed to record the formation of vascular blockage and the injury and regeneration of small vessels during cerebral ischemia recovery. The results showed that 30 min of laser irradiation could completely block the cortical vessels in rats. Within 24-48 h after ischemia, the degree of brain injury was the greatest, and the number of blood vessels in the ischemic region reached the minimum. Then the blocked blood vessels began to be dredged, and the small blood vessels around the ischemic area began to regenerate. Small blood vessels in the superficial/deep layers of the cortex disappeared significantly after laser irradiation. During 10 d after ischemia, the blocked blood vessels were gradually dredged and recovered. On the 10th day after laser irradiation, a large number of neovascularization appeared in the superficial layer of cortex, but the deep vessels did not recover. These results indicate that the method established in this study can observe the changes of blood vessel in cerebral ischemic region continuously, which lays a foundation for further quantitative study on the dynamics of embolized blood vessels and peripheral capillaries during the recovery of cerebral ischemia.
Animals ; Brain ; blood supply ; Brain Ischemia ; Cerebral Cortex ; blood supply ; Rats ; Regeneration

OBJECTIVETo investigate the instant changes in heart function and organ blood flow, and their relations in rats at early stage of severe burn.

METHODSThirty-six SD rats were divided into sham injury group (S, n = 6) and burn group (B, n = 30) according to the random number table. Rats in B group were subjected to 30% TBSA full-thickness burn. Five time points for observation: 10 and 30 minutes, and 1, 3, and 6 hour (s) post injury (PIM/H) were set up, with 6 rats at each time point. Rats in S group were sham scalded with 37 degrees C warm water. Hemodynamics indexes including heart rate (HR), mean artery pressure (MAP), left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), LV + or - dp/dt max were determined. Blood flow of heart, brain, kidney, spleen, stomach, and ileum was determined respectively with fluorescent microspheres method. The correlation between LV + or - dp/dt max and myocardial blood flow was analyzed.

RESULTS(1) Compared with those of S group, HR in B group decreased gradually after injury; MAP, LVSP, LV +dp/dt max, LV -dp/dt max and myocardial blood flow in B group decreased obviously at PIM 10 (with F value respectively 12.062, 12.629, 11.066, 18.374, 9.468, and P values all below 0.01). Among them, myocardial blood flow decreased from (6.8 + or - 0.8) mL x min(-1) g(-1) to (2.6 + or - 0.5) mL x min(-1) x g(-1). Above-mentioned indexes increased gradually as the time after injury went on, with the highest values (except for LV +dp/dt max) observed at PIH 1, which decreased again later, with values at PIH 3 and 6 significantly lower than those in S group (the same F values as above, P values all below 0.01). There was no obvious difference in LVEDP between S group and B group at each time point (F = 1.205, with P values all above 0.05). (2) Compared with those of S group, blood flow of kidney, spleen, stomach, and ileum of rats in B group at PIM 10 declined obviously (with F value respectively 22.694, 20.856, 12.653, 7.293, P < 0.05 or P < 0.01), but the decline range was smaller than that in heart. The lowest values of above-mentioned indexes were observed at PIH 1 or PIH 3. Brain blood flow of rats in B group at each time point was close to that in S group (F = 1.812, with P values all above 0.05). (3) The correlation coefficient r between LV +dp/dt max, LV -dp/dt max and myocardial blood flow was respectively 0.651 and 0.617, showing significant positive correlation (with t value respectively 4.456 and 4.222, and P values all below 0.01).

CONCLUSIONSThe myocardial ischemia and decrease in cardiac function may occur in a very short time after severe burn (PIM 10). The rapid decrease of heart blood flow plays an important role in the change in cardiac function. Myocardial damage and decrease of cardiac function may be one of the important factors result in the decline of blood flow in other organs.

Animals ; Brain ; blood supply ; Burns ; physiopathology ; Disease Models, Animal ; Heart ; physiopathology ; Hemodynamics ; Ileum ; blood supply ; Kidney ; blood supply ; Male ; Myocardial Ischemia ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Regional Blood Flow ; Spleen ; blood supply ; Stomach ; blood supply

AIMTo isolate and purify the brain microvessels without intact neural cells used for cloning specific gene at the blood-brain-barrier.

METHODSMagnetic beads ranging from 200-500 nm were synthesized and infused into cerebral spheres through carotid arteries. The brain tissues were dissected by mechanic and enzymatic methods, and sieved to discharge tissues and large blood vessels. The brain microvessels labelled by magnetic beads were sorted in magnetic fields, and identified by morphology, molecular biology and biologic activity.

RESULTSScanning electric micrograph of the obtained brain microvessels showed the vessels grossly free of adjoining neural cells except an occasional nerve ending. RT-PCR products of microtube-associated protein 2a, glutamine synthetase and CD31 from brain tissue had positive lanes, but only CD31 had positive lanes from isolated microvessels. The endothelial cells from isolated microvessels had more fluorescence than that from cultured endothelial cells.

CONCLUSIONHighly purified microvessels without intact neural cells can be obtained by this method.

Animals ; Blood-Brain Barrier ; anatomy & histology ; Brain ; blood supply ; Microvessels ; anatomy & histology ; Rats

OBJECTIVE: To summarize our experience of successful and failed management in 8 huge lobulated nasopharyngeal angiofibromas with intracranial extensions, and introduce some key points of perioperative treatments. METHOD: Eight male case with an average age of 18 years, were all lobes extending into middle and/or anterior cranial fossa, in which 5 cases revealed blood supply from the internal carotid arteries and 3 cases were reoperated because of recurrence. Preoperatively, the tumor were evaluated by CT, CTA, MRI and/or MRA, and super selective embolization of the feeding arteries were crucial procedures. The combined craniofacial approaches were used to excise these tumors. RESULT: Five cases were removed completely, and 3 cases were removed partly in which 2 were due to serious bleeding caused by lack of DSA technique at that time and 1 were due to neglecting the tumor lobe in the sphenoid sinus of the other side. CONCLUSION Reasonable perioperative management are very important for control of intra-operative blood loss, complete remodeling of the tumor and avoiding complication.
Adolescent ; Angiofibroma ; blood supply ; pathology ; surgery ; Brain Neoplasms ; blood supply ; secondary ; surgery ; Carotid Artery, Internal ; Humans ; Male ; Nasopharyngeal Neoplasms ; blood supply ; pathology ; surgery ; Neoplasm Invasiveness ; Treatment Outcome

OBJECTIVETo evaluate the changes of cerebral blood flow (CBF) with real-time contrast-enhanced ultrasound (CEU) in a canine model of acute cerebral ischemia.

METHODSCerebral perfusion was assessed in 6 dogs subjected to craniotomy with CEU at the time of 0, 30, 60, 90 and 120 min after occlusion of the left common carotid artery (LCCA). The microvascular volume (A) and blood flow velocity (beta) in the brain were measured from the time-versus-acoustic intensity plots, and the value of Axbeta were calculated. 99mTc-ECD brain single photon emission computed tomography (SPECT) was performed on the day before the experiment and at 120 min after LCCA occlusion. The radioactive counts on both sides of the cerebral cortex were calculated.

RESULTSA significant correlation was found between Axbeta from CEU and volume of the blood flow of the CCA from Doppler flowmetry. A, beta and Axbeta values varied significantly between the different time points (P>0.001). The ipsilateral hemisphere showed a low-perfusion state while the contralateral hemisphere showed a high-perfusion state immediately after the occlusion.

CONCLUSIONSThe changes of beta is the main regulation mechanism during acute cerebral ischemia in dogs.

Animals ; Blood Flow Velocity ; Brain ; blood supply ; Brain Ischemia ; diagnostic imaging ; Cerebrovascular Circulation ; Dogs ; Male ; Regional Blood Flow ; Ultrasonography

OBJECTIVETo observe the three-dimensional distribution of vessels, and to establish a new method for measurement of blood flow velocity in mice cerebral cortex using two-photon laser scanning microscopy and fluorescence probe labeling technique.

METHODSThe mouse was made cranial window surgery and injected Texas-Red through tail vein after anesthetized. The three-dimensional imaging of vessel was obtained through z-stack scanning, and blood flow velocity was quantified through line scanning.

RESULTSWe could detect vascular distribution for more than 500 µm depth using two-photon microscopy. The velocity of blood flow was (0.59 ± 0.12) mm/s in capillary.

CONCLUSIONThe method for observing the brain blood flow by two-photon microscopy was established, which could achieve quantification of single vascular blood flow velocity and provide experimental evidence for basic research and medical applications.

Animals ; Blood Flow Velocity ; Brain ; blood supply ; Capillaries ; Cerebrovascular Circulation ; Fluorescent Dyes ; Hemodynamics ; Mice ; Microscopy, Fluorescence

In this paper, the Fourier transform based minimum mean square error (FT-based MMSE) method is used to calculate the regional cerebral blood volume (rCBV) in magnetic resonance (MR) perfusion imaging, and the method is improved to handle the existing noise in the imaging process. In the experiments with signal-to-noise ratio (SNR) of 50 dB, the rCBV values were compared with the results using MMSE method. The effects of different SNRs on the estimation of rCBV were analyzed. The experimental results showed that MMSE was a simple way to filter the measurement noise, and could calculate rCBV accurately. Compared with other existing methods, the present method is not sensitive to environment, and furthermore, it is suitable to deal with the perfusion images acquired from the environment with larger SNR.
Blood Volume ; Brain ; blood supply ; Fourier Analysis ; Humans ; Magnetic Resonance Angiography

The relationship of affected regions, cause of disease, pathogenesis of flaccidity with physiological functions of the Governor Vessel is expounded, indicating that "skin, muscle, tendon, vessel and joint" are basic structures of performing motor function of the organism, which depend on nourishing of qi, blood, body fluid, essence and marrow; "insufficiency of essence and marrow" and "deficiency of qi and blood" are keys of pathogenensis of flaccidity; "deficiency or obstruction of the Governor Vessel" and "yang of the Governor Vessel unable to function" are the basis of channels and collaterals for flaccidity attack. Clinically, regulation of the Governor Vessel can promote repair of morphosis and functions of the Governor Vessel (brain and spinal cord), and rebuilding of the regulative system of the brain-the Governor Vessel (spinal cord)-viscera-channels, qi and blood functional activities, so as to restore the normal distribution and transduction of qi, blood, body liquid, essence and marrow to nourish skin, muscle, tendon, vessel and joint.
Acupuncture Therapy ; methods ; Blood Vessels ; physiology ; Brain ; blood supply ; Humans ; Medicine, Chinese Traditional ; Muscle Hypotonia ; etiology ; therapy ; Qi ; Spinal Cord ; blood supply

The main purpose of this paper is to describe the design and development of the near-infrared blood-oxygen monitor which is based on the theory of detecting the blood-oxygen parameters of tissue by near-infrared, and the monitor can detect the blood-oxygen parameters of two sides of the local brain tissue. The monitor uses two wavelength ultra-high light LED as lamp-house, and two sensors detect the light scattered by two sides of the local brain tissue, which make the monitor achieve the function of dual detector. The appearance of the monitor's detector is designed to reduce effectively the noise brought by the background and alleviate the discomfort feelings of the patient. At the same time, this apparatus can monitor continuously the brain blood-oxygen parameters of the patients in real time, and output the curves of the blood-oxygen and oxygen concentration of two sides of brain tissue. At last, the biological model experiments and the tests in clinical setting validate the monitor.
Blood Gas Analysis ; instrumentation ; methods ; Brain ; blood supply ; Humans ; Monitoring, Physiologic ; instrumentation ; Oximetry ; instrumentation ; methods ; Oxygen ; blood ; Spectroscopy, Near-Infrared