ABSTRACT
Evidence suggested that glycogen synthase kinase-3β (GSK-3β) is involved in Nogo-66 inhibiting axonal regeneration in vitro, but its effect in vivo was poorly understood. We showed that stereotactic injection of shRNA GSK-3β-adeno associated virus (GSK-3β-AAV) diminished syringomyelia and promoted axonal regeneration after spinal cord injury (SCI), using stereotactic injection of shRNA GSK-3β-AAV (tested with Western blotting and RT-PCR) into the sensorimotor cortex of rats with SCI and by the detection of biotin dextran amine (BDA)-labeled axonal regeneration. We also determined the right position to inject into the sensorimotor cortex. Our findings consolidate the hypothesis that downregulation of GSK-3β promotes axonal regeneration after SCI.
Subject(s)
Animals , Humans , Rats , Axons , Metabolism , Dependovirus , Genetics , Glycogen Synthase Kinase 3 beta , Genetics , Metabolism , Nerve Regeneration , Genetics , RNA, Small Interfering , Genetics , Sensorimotor Cortex , Pathology , Spinal Cord Injuries , Genetics , Pathology , Therapeutics , Syringomyelia , Genetics , Pathology , TherapeuticsABSTRACT
The expression changes of Rars gene in ischemia-injured neurons were investigated by detecting its translational product arginyl-tRNA synthetase (ArgRS), and the inhibitory effects of ischemic preconditioning (IPC) on Rars gene were explored. Both IPC model and prolonged ischemia (PI) model were established by using the classic oxygen glucose deprivation (OGD) method. The primary cultured neurons were assigned into the following groups: the experimental group (IPC+PI group), undergoing PI after a short period of IPC; the conditional control group (PI control group), subjected to PI without IPC; blank control group, the normally cultured neurons. The Rars transcriptional activities and ArgRS expression levels were measured at different time points after re-oxygenation (3 h/6 h/12 h/24 h). Data were collected and statistically analyzed. Compared to the blank control group, the Rars activities and ArgRS levels were significantly increased in PI control group, peaking at the time point of 6 h after re-oxygenation. Rars activities and ArgRS levels were significantly lower in the experimental group than in the PI control group at different time points after re-oxygenation. PI insult can induce an escalating activity of Rars and lead to ArgRS over-expression in primary cultured neurons. IPC can inhibit the increased Rars activity and down-regulate ArgRS expression of ischemia-insulted neurons. This mechanism may confer ischemic tolerance on neurons.
Subject(s)
Animals , Humans , Rats , Arginine-tRNA Ligase , Genetics , Metabolism , Brain Ischemia , Genetics , Metabolism , Pathology , Gene Expression Regulation , Genetics , Glucose , Metabolism , Ischemic Preconditioning , Methods , Neurons , Metabolism , Pathology , Oxygen , Metabolism , Primary Cell CultureABSTRACT
Aminoacyl-tRNA syntheses (AARS) can catalyze the adenosine triphosphate (ATP)-dependent acylation of their cognate tRNA(s) with a specific amino acid. They can be seen as an index to reflect the energy metabolic rate of ischemic brain cells in ischemic penumbra. This study examined the relationship between arginyl-tRNA synthetase (ArgRS), one of the AARS, and cerebral ischemia in rats. The model of middle cerebral artery occlusion (MCAO) was established in rats. The expression levels of ArgRS protein and mRNA were detected in rat brain tissues at different time points following MCAO by Western blotting and RT-PCR, respectively. The results showed that the MCAO model was successfully established. Western blotting and RT-PCR analysis revealed that the ArgRS protein and mRNA were expressed in brain cells in both ischemic and normal penumbra tissues. The expression levels of ArgRS protein and mRNA peaked at 6 h after MCAO and decreased gradually. At 24 h, the expression levels of ArgRs protein and mRNA in ischemic penumbral tissues were lower than those in normal tissues. The expression levels of ArgRS mRNA and protein in ischemic penumbra varied with ischemic time, suggesting that the energy metabolism of brain cells in penumbra changed dynamically after ischemia to ensure the endogenous self-protection of the body. The brain oxygen supply should be improved as soon as possible, especially within 6-12 h after ischemia, so as to meet the demand for energy metabolism in ischemic penumbra and make sure the cell structure remains stable.
Subject(s)
Animals , Humans , Rats , Arginine-tRNA Ligase , Brain Ischemia , Genetics , Pathology , Energy Metabolism , Gene Expression Regulation , Oxygen Consumption , RNA, MessengerABSTRACT
The clinical characteristics of patients who presented in poor clinical grade due to ruptured middle cerebral artery aneurysms (MCAAs) associated with large sylvian hematomas (SylH) were analyzed and an ingenious designed prophylactic hinged craniectomy was introduced. Twenty-eight patients were graded into Hunt-Hess grades IV-V and emergency standard micro-neurosurgeries (aneurysm clipping, hematoma evacuation and prophylactic hinged craniectomy) were performed, and their clinical data were retrospectively analyzed. 46.43% of the patients reached encouraged favorable outcomes on discharge. The favorable outcome group and the poor outcome group significantly differed in terms of patients' anisocoria, Hunt-Hess grade before surgery, extent of the midline shift and time to the surgery after bleeding (P0.05). However, ingenious designed prophylactic hinged craniectomy efficiently reduced the patients' intracranial pressure (ICP) after surgery. It was suggested that preoperative conditions such as Hunt-Hess grading, extent of the midline shift and the occurrence of cerebral hernia affect the prognosis of patients, but time to the surgery after bleeding and prophylactic hinged craniectomy are of significant importance for optimizing the prognosis of MCAA patients presenting with large SylH.
ABSTRACT
Aminoacyl-tRNA syntheses (AARS) can catalyze the adenosine triphosphate (ATP)-dependent acylation of their cognate tRNA(s) with a specific amino acid. They can be seen as an index to reflect the energy metabolic rate of ischemic brain cells in ischemic penumbra. This study examined the relationship between arginyl-tRNA synthetase (ArgRS), one of the AARS, and cerebral ischemia in rats. The model of middle cerebral artery occlusion (MCAO) was established in rats. The expression levels of ArgRS protein and mRNA were detected in rat brain tissues at different time points following MCAO by Western blotting and RT-PCR, respectively. The results showed that the MCAO model was successfully established. Western blotting and RT-PCR analysis revealed that the ArgRS protein and mRNA were expressed in brain cells in both ischemic and normal penumbra tissues. The expression levels of ArgRS protein and mRNA peaked at 6 h after MCAO and decreased gradually. At 24 h, the expression levels of ArgRs protein and mRNA in ischemic penumbral tissues were lower than those in normal tissues. The expression levels of ArgRS mRNA and protein in ischemic penumbra varied with ischemic time, suggesting that the energy metabolism of brain cells in penumbra changed dynamically after ischemia to ensure the endogenous self-protection of the body. The brain oxygen supply should be improved as soon as possible, especially within 6-12 h after ischemia, so as to meet the demand for energy metabolism in ischemic penumbra and make sure the cell structure remains stable.
ABSTRACT
The clinical characteristics of patients who presented in poor clinical grade due to ruptured middle cerebral artery aneurysms (MCAAs) associated with large sylvian hematomas (SylH) were analyzed and an ingenious designed prophylactic hinged craniectomy was introduced. Twenty-eight patients were graded into Hunt-Hess grades IV-V and emergency standard micro-neurosurgeries (aneurysm clipping, hematoma evacuation and prophylactic hinged craniectomy) were performed, and their clinical data were retrospectively analyzed. 46.43% of the patients reached encouraged favorable outcomes on discharge. The favorable outcome group and the poor outcome group significantly differed in terms of patients' anisocoria, Hunt-Hess grade before surgery, extent of the midline shift and time to the surgery after bleeding (P<0.05). There were no significant differences in age, sex, volume and location of the hematoma, size of aneurysm between the favorable and poor groups (P>0.05). However, ingenious designed prophylactic hinged craniectomy efficiently reduced the patients' intracranial pressure (ICP) after surgery. It was suggested that preoperative conditions such as Hunt-Hess grading, extent of the midline shift and the occurrence of cerebral hernia affect the prognosis of patients, but time to the surgery after bleeding and prophylactic hinged craniectomy are of significant importance for optimizing the prognosis of MCAA patients presenting with large SylH.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Cerebral Aqueduct , Pathology , Craniotomy , Methods , Hematoma , Intracranial Aneurysm , General Surgery , Retrospective Studies , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
A kind of thrombus-targeted lipid-coated microbubbles were prepared, and the target property of the microbubbles and the effects of different methods detecting thrombosis in vessels were observed. Phospholipid-coated microbubbles were prepared by membrane-hydration method. Thrombus-targeted lipid-coated fluorocarbon microbubbles were labeled with specific fluorescence and then integrated to the thrombus in vivo and ex vivo through an avidin biotin system. The thrombus was immediately observed for the distribution and property of the thrombus-targeted microbubbles under the optical microscope, fluorescence microscope and transmission electron microscope. The carotid thrombosis models were set up in rabbits, and the effects of different methods detecting thrombosis in vessels were observed. The diameter of the phospholipid-coated microbubbles was 0.8-2.5 μm, and even reached nanoscale in some of them. The zeta electric potential was about -11 mV and the concentration was about 1.08×10(10)/mL. Immunofluorescence of rapid frozen sections in vivo and ex vivo showed that massive targeted lipid-coated microbubbles flocked around fresh blood clots and some aggregated within them under the light and fluorescence microscope. The number of aggregated microbubbles ex vivo was greater than that observed in the experiment in vivo, and the fluorescence observed in the experiment ex vivo was stronger than that in the experiment in vivo. The same imaging was observed under the electron microscope. Models of carotid thrombosis in rabbits were established successfully. Effects of detecting thrombosis by means of thrombosis-targeted microbubble ultrasonoraphy and Sono Vue ultrasonography in vessels were more satisfactory than those by Color Doplor Flow Imaging (CDFI), ordinary microbubbles and Three Dimensions-time of flight MR angiography (3D-TOF-MRA) (P<0.01). Compared to ordinary microbubbles ultrasonography, thrombosis-targeted microbubbles ultrasonography had the advantages whenever in imaging quality or in imaging time. Thrombus-targeted phospholipid-coated microbubbles were prepared successfully by membrane-hydration method. They could aggregate rapidly in fresh blood clots and enter deep into the internal part of the thrombus both in vivo and ex vivo, and had the targeted property of strongly conjugating with the thrombus. Compared to other thrombosis detection methods, ultrasonography with thrombosis-targeted microbubbles has obvious advantages in detecting thrombosis in vessels, mainly in: non-invasiveness, safety, good image quality, accuracy, and longer imaging time.
ABSTRACT
A kind of thrombus-targeted lipid-coated microbubbles were prepared, and the target property of the microbubbles and the effects of different methods detecting thrombosis in vessels were observed. Phospholipid-coated microbubbles were prepared by membrane-hydration method. Thrombus-targeted lipid-coated fluorocarbon microbubbles were labeled with specific fluorescence and then integrated to the thrombus in vivo and ex vivo through an avidin biotin system. The thrombus was immediately observed for the distribution and property of the thrombus-targeted microbubbles under the optical microscope, fluorescence microscope and transmission electron microscope. The carotid thrombosis models were set up in rabbits, and the effects of different methods detecting thrombosis in vessels were observed. The diameter of the phospholipid-coated microbubbles was 0.8-2.5 μm, and even reached nanoscale in some of them. The zeta electric potential was about -11 mV and the concentration was about 1.08×10(10)/mL. Immunofluorescence of rapid frozen sections in vivo and ex vivo showed that massive targeted lipid-coated microbubbles flocked around fresh blood clots and some aggregated within them under the light and fluorescence microscope. The number of aggregated microbubbles ex vivo was greater than that observed in the experiment in vivo, and the fluorescence observed in the experiment ex vivo was stronger than that in the experiment in vivo. The same imaging was observed under the electron microscope. Models of carotid thrombosis in rabbits were established successfully. Effects of detecting thrombosis by means of thrombosis-targeted microbubble ultrasonoraphy and Sono Vue ultrasonography in vessels were more satisfactory than those by Color Doplor Flow Imaging (CDFI), ordinary microbubbles and Three Dimensions-time of flight MR angiography (3D-TOF-MRA) (P<0.01). Compared to ordinary microbubbles ultrasonography, thrombosis-targeted microbubbles ultrasonography had the advantages whenever in imaging quality or in imaging time. Thrombus-targeted phospholipid-coated microbubbles were prepared successfully by membrane-hydration method. They could aggregate rapidly in fresh blood clots and enter deep into the internal part of the thrombus both in vivo and ex vivo, and had the targeted property of strongly conjugating with the thrombus. Compared to other thrombosis detection methods, ultrasonography with thrombosis-targeted microbubbles has obvious advantages in detecting thrombosis in vessels, mainly in: non-invasiveness, safety, good image quality, accuracy, and longer imaging time.
Subject(s)
Animals , Female , Male , Rabbits , Carotid Artery Thrombosis , Diagnostic Imaging , Contrast Media , Drug Compounding , Methods , Image Enhancement , Methods , Lipids , Microbubbles , Reproducibility of Results , Sensitivity and Specificity , Ultrasonography , MethodsABSTRACT
<p><b>OBJECTIVE</b>The hypoxic-ischemic encephalopathy caused by asphyxia in peripartum is a serious disease in newborn infants, with a high disability and mortality rate. Lack of regenerative ability in central nervous system after injury is considered as the fundamental cause. However, in recent years many studies have revealed that there are myelin-associated neurite growth inhibitory factors that exert inhibiting effect through the Nogo receptor (NgR). This study aimed to investigate the expression level of NgR and the possible neuroprotective effect of NEP1-40 in newborn rats with hypoxic ischemic brain damage (HIBD).</p><p><b>METHOD</b>Eighty healthy Wistar rats aged 7 days were randomly divided into 4 groups; 8 in control group, 24 in HIBD model group, 24 in GM-1 group and 24 in NEP1-40 group. The rats of the control group and HIBD group were injected with normal saline (0.25 ml/kg) intraperitoneally, while those in NEP1-40 group and GM-1 group with NEP1-40 12.5 microg/d, GM-1 10 mg/(kg.d) for continuous 3 days of 72-hour group or 7 days of 168-hour group, respectively. In situ hybridization was adopted for detecting the expression of NgR in the brain of the rats at the time point of 24 hours, 72 hours and 7 days. Meanwhile histopathological changes of neurons and axon were detected by transmission electron microscopy (TEM). The SPSS statistical software package for Windows, version 10.0, was used to run Chi-square tests and least significance difference (LSD-t) on the data presented, and P value of less than 0.05 was regarded as statistically significant.</p><p><b>RESULT</b>The expression level of Nogo-A receptor in the control group was higher than that of the other groups at different time point (t value was 5.48, 6.11, 6.96, 8.24, 5.99 and 5.34, respectively, and all P values were less than 0.05). There were no significant differences in Nogo-A receptor level among the HIBD group, the GM-1 group and the NEP1-40 at 24 hours (t was 1.48, 2.76 and 1.29, respectively, and all P > 0.05), while the expression of Nogo-A receptor of NEP1-40 at 72 hours and 7 days was lower than that of the HIBD group and the GM-1 group at the same time point, respectively (all P < 0.05). Repair of neurons in damaged brain to some extent was found after GM-1 treatment and satisfactory repair of neurons and axon regeneration was obtained with NEP1-40 administration as shown by TEM.</p><p><b>CONCLUSION</b>Hypoxic ischemic brain damage can down-regulate the expression of Nogo-A receptor in the central nervous system. NEP1-40 contributes to the regeneration of axon and repair of brain damage, thus exerts neuroprotective effect.</p>
Subject(s)
Animals , Rats , Animals, Newborn , Brain , Metabolism , Pathology , GPI-Linked Proteins , Hypoxia-Ischemia, Brain , Metabolism , Pathology , Myelin Proteins , Pharmacology , Nogo Receptor 1 , Peptide Fragments , Pharmacology , Rats, Wistar , Receptors, Cell Surface , Receptors, Peptide , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of wt p53 gene transfection on the sensitivity of hyperthermia in C6 glioma.</p><p><b>METHODS</b>The recombinant eukaryotic expressive vector pCMV-p53 plasmids were extracted, identified and transmitted to C6 glioma cells by stable transfection. The biological characteristics were compared among C6/p53 (+) cells, thermo-treated C6/p53 (+) cells, thermo-treated C6 cells, thermotolerance C6 cells and control C6 cells. Transplanted glioma was treated by laser interstitial thermotherapy (LITT) in tumor-bearing nude mice.</p><p><b>RESULT</b>The wt p53 gene segments were extracted and correctly identified by restriction enzyme (Hind and EcoR). The optimal transfection concentration of plasmid to liposome was 1:6, neo gene expressed stably in C6 cells transfected with positive and blank plasmid. Thermotolerance C6 cell growth was normal in vitro, growth of C6/p53 (+) cells was inhibited. Growth of hyperthermia treated C6 cells was inhibited significantly 12 h after thermal treatment, cell proliferation activity of C6/p53 (+) cells was suppressed significantly 6 h after hyperthermia treatment. Apoptosis was observed in C6/p53 (+), thermo-treat C6 and thermo-treat C6/p53 (+) cells. The apoptosis ratio of hyperthermia treated C6/p53(+) cells was increased by 30 folds compared with that of control groups. Study in nude mouse model demonstrated lower positive inoculation rate in groups of C6/p53 (+) cells (57 %), hyperthermia treated C6 cells (75 %) and hyperthermia treated C6/p53(+) cells (20 %). C6/p53(+) LITT group showed the highest antitumor effect, compared with C6 LITT group(P<0.05). However, thermotolerance C6 LITT group had the lowest effect.</p><p><b>CONCLUSION</b>Transfection of wt p53 gene can increase the sensitivity of hyperthermia in glioma cells.</p>
Subject(s)
Animals , Mice , Rats , Brain Neoplasms , Genetics , Pathology , Cell Line, Tumor , Glioma , Genetics , Pathology , Hyperthermia, Induced , Transfection , Tumor Suppressor Protein p53 , GeneticsABSTRACT
<p><b>OBJECTIVE</b>Nogo-A is an axon regeneration inhibitor, and its function in central nervous system (CNS) is still unknown. The present study is to explore the relationship between the expression of Nogo-A and the malignancy of oligodendroglial tumors in patients.</p><p><b>METHODS</b>Tumor tissue samples with different malignancy grade were obtained from the hospitals. The samples used for detection had been diagnosed as oligodendroglial tumors (oligodendroglioma or anaplastic oligodendroglioma). The expression of Nogo-A was detected by immunohistochemistry and western-blot analysis. The correlation test between the Nogo-A expression and the morphological changes (the percentages of atypical cells and mitotic cells in the tumors) related to the malignancy of tumor tissues was performed.</p><p><b>RESULTS</b>There was significant negative correlation between the Nogo-A expression and the morphological change of tumor tissues according to immunohistochemistry. Western-blot analysis also indicated that the gray value of Nogo-A protein band in the oligodendroglioma group was significantly higher than that in the anaplastic oligodendroglioma group.</p><p><b>CONCLUSION</b>Nogo-A expression was negatively correlated with the malignancy grade of oligodendroglial tumors.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Biomarkers, Tumor , Metabolism , Brain Neoplasms , Diagnosis , Metabolism , Down-Regulation , Physiology , Immunohistochemistry , Mitotic Index , Myelin Proteins , Metabolism , Neoplasm Invasiveness , Diagnosis , Nogo Proteins , Oligodendroglioma , Diagnosis , Metabolism , Predictive Value of TestsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the applied value of magnetoencephalography (MEG) localization in microsurgery of brain tumors in the region of motor cortex.</p><p><b>METHODS</b>From January 2003 to April 2005, 36 patients with 19 meningomas, 14 gliomas, 2 metastases and 1 cavernous angioma underwent MEG and MRI before operation. These individualized functional brain maps were integrated into a neuronavigation system. Preoperative mapping of somatosensory and/or motor cortex was performed, and sites were compared, and all tumors were resected microsurgerically.</p><p><b>RESULTS</b>A space-occupying lesion could change the region of motor cortex in all the patients. Thirty-four cases were resected totally. The patient's myodynamia after operation improved in 19 cases, unchanged in 15 cases, descended in 2 cases.</p><p><b>CONCLUSIONS</b>MEG is an effective localization method of function, providing the relationship between the region of motor cortex and the tumor. And it is valuable for accurate planning in the treatment of brain tumors in the region of motor cortex.</p>
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Brain Neoplasms , Diagnosis , General Surgery , Magnetoencephalography , Microsurgery , Neuronavigation , Neurosurgical Procedures , Methods , Treatment OutcomeABSTRACT
Objective To explore the effects of chronic electrical stimulation (ES) on Nogo-A expression in the hippoeampus of rats.Methods Thirty male Wistar rats were randomly divided into a control group and 4 exper- imental groups.The rats in the control group were given sham ES,while those in the experimental groups received 1, 3,6,or 9 days of ES before being sacrificed for the detection of Nogo-A expresson in the hippoeampus by immunohis- tochemistry and Western plotting.Results There was a positive correlation between the level of Nogo-A expression and the duration of ES,as shown by the immunohistochemistry technique.Western blotting showed the same result. Conclusion In general,seizure occurred 8 days after electrical stimulation began.Elevated Nogo-A expression in the hippocampus began earlier than seizures in the epilepsy model groups.
ABSTRACT
Objective To observe the expressions of matrix metalloproteinase-9 mRNA and the change of cerebral edema after diffuse brain injury in rats and discuss their correlation.Methods Marmaruu's diffuse brain injury model of rat was made.Real-time quantitative RT-PCR,dry-wet meth- od,histological techniques and electron microscope were used to determine the expressions of MMP-9 containing water in brain tissue and inflammatory reaction and uhrastructural changes of blood capillary at different time phases after truama.Results The expressions of MMP-9 mRNA started to increase at 1 hour,peaked at 12 hours(P