Cloning and characterization of a monoterpene synthase gene from Tripterygium wilfordii / 中国中药杂志

Tripterygium wilfordii is a medicinal plant commonly used in the treatment of rheumatoid arthritis,and with pharmacological activities in anti-tumor and obesity treatment. The known active ingredients in T. wilfordii are mainly terpenoids,but with very low content. Therefore,the analysis of the biosynthesis pathway of terpenoids in T. wilfordii has become a research hotspot to solve the problem of its resources. Terpenoid synthase( TPS) is a key enzyme that catalyzes the formation of a wide variety of terpenoid skeletons. In this study,a gene fragment with an ORF of 1 785 bp was cloned from T. wilfordii. Bioinformatics analysis was performed using NCBI's BLASTP,ProtParam and Interpro online tools and MEGA 6.0 software. The response of this gene to methyl jasmonate was also detected by real-time fluorescent quantitative PCR,and its catalytic function was verified by prokaryotic expression and in vitro enzymatic assay. Bioinformatics analysis indicated that the amino acid sequence encoded by this gene had both N-terminal domain and C-terminal domain of TPS,as well as the DDxx D conserved domain of the class I of TPS family. And Tw MTS gathered together with TPS-b subfamily in the Neighbor-Joining Tree constructed with known homologous TPSs. The results of RT-PCR showed that 50 μmol·L-1 MeJA 12 h could increase the expression of Tw MTS to 735 times in the control group at 12 h,and 1 644 times at 24 h. In addition,in vitro enzymatic reaction results showed that Tw MTS can catalyze the production of β-citronellol with GPP as substrate,indicating that Tw MTS was a monoterpene synthase. The above results provided a new element for the synthetic biology database of T. wilfordii terpenoids,and laid the foundation for future biosynthesis research.

Analysis of flavonoids and antitumor activity of transgenic Saussurea involucrate / 中国中药杂志

The aim of this paper was to investigate the flavonoids of callus of transgenic and non-transgenic Saussurea involucrate and its antitumor activity on the esophageal cancer CaEs-17 cells. The species and content of mono-phenols were detected by high performance liquid chromatography. The growth of human esophageal cancer CaEs-17 cells was detected using CCK-8 assay, apoptosis morphology observation and flow cytometry. Expression of related apoptotic genes Bax and Bcl-2 were determined by qPCR. The results showed that the content of total flavonoids in the transgenic callus was 2.72 times that of the non-transgenic callus. The cyanidin-galactoside was detected in the transgenic callus, but not in the non-transgenic callus. The inhibitory effect of the extracts from the transgenic callus on CaEs-17 cells was more significant than that of the non-transgenic callus, and the IC₅₀ value had a decreased of 26.4%. Flow cytometry analysis results showed that the apoptosis induction effect of the extracts from the transgenic callus on CaEs-17 cells was significantly better than that of the non-transgenic callus. Fluorescence quantitative PCR analysis results showed that the extracts from the transgenic callus could up-regulate the expression of proapoptotic gene Bax and down-regulate the expression of apoptotic gene Bcl-2, and the regulation effect of the transgenic callus was more significant. Therefore, compared with the non-transgenic callus, the antitumor activity of the extracts from the callus of transgenic S. involucrate on the esophageal cancer CaEs-17 cells was significantly increased, which was closely related to the accumulation of cyanidin-galactoside and its metabolism-related flavonoid compounds in the transgenic callus.

Anesthetic considerations of an emergency decompressive craniotomy complicated with Ebstein's anomaly and atrial septal defect / 中华医学杂志(英文版)

Despite considerable published papers regarding Ebstein's anomaly (EA) patients receiving open-heart tricuspid valve replacement, non-cardiac emergency surgeries were rarely reported. We report a case of emergency decompressive craniotomy in a patient with EA. Anesthesiologists should pay special attention to the complications and anesthetic management during the non-cardiac surgeries performed in EA patients.

Clinical application of neuronavigation in transsphenoidal microsurgery of pituitary adenomas / 中华外科杂志

<p><b>OBJECTIVES</b>To summarize the experiences in clinical application of neuronavigation in transsphenoidal microsurgery of specific pituitary adenomas, and to discuss its indications.</p><p><b>METHODS</b>From January 2006 to December 2010, 138 cases of transsphenoidal microsurgery for specific pituitary adenomas under neuronavigation were reviewed. The indications for neuronavigation in transsphenoidal microsurgery includes: recurrent or regrowth of residual pituitary adenomas after former transsphenoidal surgery in 36 cases, invasive pituitary adenomas in 45 cases, extremely laterally or deeply situated microadenomas in 45 cases, poor pneumatization of the sphenoid in 4 cases, skull base anomalies due to osteodysplasia fibrosa in 3 cases, narrow space between bilateral internal carotid arteries in 4 cases, distortion of nasal septum in 1 case.</p><p><b>RESULTS</b>In the recurrence group, 12 were totally removed, 9 subtotally removed; postoperative complications included hematoma within the tumor cavity in 2 cases, cerebrospinal fluid (CSF) leakage in 4 cases among which 3 developed intracranial infection and 2 communicating hydrocephalus, oculomotor paralysis in 1 case and hypopituitarism in 3 cases; 9 were cured and 8 remission. In the invasive group, 5 were totally removed, 27 subtotally removed; postoperative complications included hematoma within the tumor cavity in 1 case, CSF leakage and intracranial infection in 1 case; 2 were cured and 22 remission. None of the 30 invasive hormone-secreting adenomas were cured or remission. The 45 cases of hormone-secreting microadenomas were all totally removed, among which 38 were cured. Among the poor sphenoid pneumatization group, total and subtotal tumor removal were achieved in 2 cases respectively with only one cured. In the skull base anomaly group, 2 were totally removed and 1 subtotally removed, with only one cured. For the cases with narrow space between bilateral internal carotid arteries and distortion of nasal septum, all were totally removed and cured.</p><p><b>CONCLUSIONS</b>Transsphenoidal microsurgery under neuronavigation can be applied for pituitary adenomas in above specific indications. It is an accurate, safe and effective approach for specific pituitary adenomas, which can not only expand the indication of transsphenoidal microsurgery for pituitary adenomas, but also reduce the harmful exposure of X-rays for the operating staff.</p>

Correlation between loss of heterozygosity on chromosome 1p and 19q and expression of MGMT, p53 and Ki-67 proteins in gliomas / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the correlation of loss of heterozygosity (LOH) on chromosome 1p and 19q with the expression of MGMT, p53 and Ki-67 proteins in gliomas.</p><p><b>METHODS</b>One hundred and forty six cases of gliomas (45 oligodendrogliomas, 42 oligodendroastrocytomas, and 59 astrocytomas) were included in this study. Their tissue and blood samples were retrospectively analyzed by PCR-denaturing high-performance liquid chromatography (DHPLC) for 1p and 19q status and by immunohistochemistry for MGMT, p53 and Ki-67 expression patterns. The correlation among them and with clinicopathological characteristics were analyzed by chi-square test and t-test.</p><p><b>RESULTS</b>In the oligodendrogliomas, the positive rate of 1p LOH was 59.8%, significantly higher than 33.9% in astrocytomas (P = 0.002), and 1p and 19q LOH was 42.5%, significantly higher than 16.9% in astrocytomas (P = 0.001). Combined with LOH on 1p and 19q, low MGMT expression (65.5%), and high Ki-67 expression (54%) were more frequent in oligodendrogliomas, whereas high p53 expression was more frequent in astrocytomas and mixed tumors (75.2%). 1p LOH (72.5%) and low MGMT (87.5%) expressions were more frequent in grade II oligodendrogliomas, whereas high expressions of p53 (83.0%) and Ki-67 (76.6%) were more frequent in grade III oligodendrogliomas. In addition, high Ki-67 expression was more frequent in grade III astrocytomas. LOH on 1p and 19q LOH was more frequent in nontemporal oligodendrogliomas (55.6%) than that in temporal ones (22.2%, P = 0.002). Non-random associations were found between LOH 1p and 19q LOH, MGMT and p53 protein expressions, and MGMT and Ki-67 protein expressions (all P < 0.05), whereas mutual exclusions were found between LOH on 1p and 19q and p53 expression, and LOH 1p and Ki-67 expression.</p><p><b>CONCLUSIONS</b>There is a significant interrelationship of the investigated molecular markers and clinicopathological features of gliomas, which support a promising role of molecular markers in guiding diagnostic assessment and clinical management of gliomas.</p>

Clinicopathologic features of endolymphatic sac tumor at cerebellopontine angle / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features and immunophenotype of endolymphatic sac tumor (ELST) and normal endolymphatic sac.</p><p><b>METHODS</b>The clinical and histologic features were evaluated in 5 cases of ELST. Eight cases of choroid plexus papilloma at cerebellopontine angle and 2 cases of normal endolymphatic sac were used as controls. Immunohistochemical study for vimentin, AE1/AE3, CK8/18, CK5/6, EMA, GFAP, synaptophysin, S-100 protein, CEA, TTF-1, VEGF, D2-40, calponin, calretinin and Ki-67 was carried out.</p><p><b>RESULTS</b>The age of onset of ELST ranged from 23 to 35 years (median = 24 years). The male-to-female ratio was 2:3. The clinical presentation was tinnitus, otalgia, hearing loss, otorrhagia with effusion and headache. The duration of symptoms ranged from 6 months to 10 years. Local recurrences were noted in 3 cases. Radiologically, the tumors were located at cerebellopontine angle and demonstrated petrous bone destruction. Histologic examination showed that the tumors had a papillary-glandular pattern. The papillae were covered by a single layer of low cuboidal cells. The tumor cells had distinct cell borders and contained eosinophilic to clear cytoplasm. The nuclei were slightly atypical and sometimes apically located. Focal dilated glandular structures with colloid-like material were also identified. The surrounding stroma was vascularized. All of the 5 cases had dural or petrous bone infiltration. Immunohistochemical study showed that all of the 5 cases were positive for AE1/AE3, CK8/18, CK5/6 and VEGF, 4 cases for EMA, 3 cases for calponin (focal), 2 cases for vimentin, 2 cases for S-100 protein, 1 case for GFAP and 1 case for synaptophysin (focal and weak). The Ki-67 index measured less than 1%. The staining for D2-40, calretinin, CEA and TTF-1 was negative. The 2 cases of the normal endolymphatic sac were positive for AE1/AE3 and CK8/18, and negative for CK5/6, EMA, S-100 protein, GFAP and synaptophysin. The 8 cases of choroid plexus papilloma were positive for synaptophysin. Seven cases were also positive for S-100 protein, 2 cases for GFAP and 1 case for D2-40. All of the 8 cases were negative for EMA, CK5/6 and calponin.</p><p><b>CONCLUSIONS</b>ELST is a rare slow-growing and potentially malignant tumor with a tendency of bone invasion and local recurrence. Distant metastasis is not observed. It must be distinguished from choroid plexus papilloma occurring at cerebellopontine angle. Correlation with clinical, radiologic and immunohistochemical findings would also be helpful.</p>

Management of pulmonary thromboembolism in post-operative neurosurgical patients / 中国医学科学院学报

<p><b>OBJECTIVE</b>To summarize the diagnosis and treatment of pulmonary thromboembolism (PTE) in post-operative neurosurgical patients.</p><p><b>METHODS</b>We retrospectively analyzed the clinical data of 7 patients who experienced pulmonary thromboembolism after neurosurgical operations in our department from October 2009 to March 2010.</p><p><b>RESULTS</b>Of these 7 patients, 6 were confirmed with computed tomographic pulmonary angiography (CTPA) and 1 was diagnosed according to the clinical manifestations and other diagnostic examinations. All the patients were treated initially with low-dose heparin or low-molecular-weight heparin and then with warfarin. Two patients were implanted with permanent inferior vena cava filters before anticoagulation. One received anticoagulant therapy and died of respiratory failure due to pulmonary embolism on the fourth post-operative day. Six patients were discharged after significant improvement.</p><p><b>CONCLUSIONS</b>Many risk factors may cause PTE peri-operatively. Post-operative CTPA may be indicated. Anticoagulation and other management strategies may be applied to improve the outcome.</p>

Neural endoscopic assisted micro-invasive management of Chiari I malformation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In order to make posterior fossa decompression for the management of Chiari I malformation simple and less invasive while using direct visualization, a novel solely endoscopic procedure has been employed for the decompression of Chiari malformation type I. The objective of this study was to present neural endoscopic posterior fossa decompression and atlas laminectomy for Chiari type I patients.</p><p><b>METHODS</b>Twenty-one patients with Chiari type I underwent neural endoscopic posterior fossa decompression and atlas laminectomy. We described the procedure for neural endoscopic posterior fossa decompression and atlas laminectomy. All patients in this series demonstrated cerebellar tonsil herniation below the foramen magnum in addition to syringomyelia. All patients in the reviewed study underwent preoperative MRI as well as 3-month postoperative MRI. Additional follow-up MRI varied but was usually repeated 12 months to 18 months after surgery. Postoperative MRI studies were retrospectively reviewed and compared with preoperative studies.</p><p><b>RESULTS</b>All patients showed clinical improvements, and none had any complications. Patients with syringomyelia had symptoms entirely disappear. Eleven patients (52.4%) experienced radiographic improvement in syringomyelia (decreased size or resolution) during the follow-up period. Nine patients (42.8%) demonstrated decreased syrinx size and four (19%) demonstrated resolved syrinx. Of the 15 patients with symptomatic syringomyelia, 11 (73.3%) experienced symptomatic improvement. The median time to symptom improvement was four months after surgery. Post surgical MRI examinations indicated complete and sufficient decompression of foramen magnum region.</p><p><b>CONCLUSIONS</b>Endoscope atlanto-occipital decompression surgery is an innovative, safe and effective surgical procedure. It has similar results compared to traditional surgery, however with the added advantages of being minimal invasive, having fewer complications, decreased influence on stability of occipital bony structure, and a faster recovery as well as reduced hospital stay and expenses.</p>

Preparation of brain targeted immunoliposomes / 药学学报

To prepare a kind of effective non-viral transduction vector, which can deliver exogenous gene into the brain, this vector can be injected through vein system and has the ability to penetrate blood brain barrier. Several groups of materials proportion, type of oil phase, water-oil ratio, phosphatides-cholesterol ratio, temperature of steaming, ultrasonic temperature and time were compared for optimization. Well-constructed immunoliposomes encapsuling LacZ gene were infused into rats through tail vein. 48 h after injection, expression product beta-galactosidase of LacZ gene was detected by histochemistry staining to convince the validity of immunoliposomes as non-viral vectors. The best proportion of synthesis immunoliposomes is as following: phosphatides-cholesterol ratio is 1:1, lipids/drug is 100:1, the type of oil phrase is dichloromethane, oil-water ratio is 4:1, temperature of steaming is 30 degrees C, ultrasonic temperature and time is 10 degrees C and 5 min. At last, 10% trehalose was added as a stabilizer. The entrapment rate is 87.24% and antibody coupling rate is 69%. When immunoliposomes were infused into rats, the expression of LacZ gene could be observed in the brain and periphery organs. Through the best proportion of materials, gene delivering immunoliposomes had been synthesized successfully. This non-viral vector can deliver exogenous gene penetrating blood brain barrier and express in the brain, and will be well-used in the field of gene therapy of cerebral diseases.

Construction of cholecystokinin transgenic mouse and its effects on food intake / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cholecystokinin (CCK) is one of the richest neuropeptides in the mammalian brain, which is mainly distributed in the cerebral cortex, hippocampus, thalamus and caudate-putamen. CCK is implicated in a variety of behavioral functions such as food intake, learning, memory, anxiety, pain and neuroprotection. The current research results for CCK are obtained mainly through injection of CCK peptide into the body. The key issues of whether CCK can regulate diet by a central pathway and whether there are long-term regulation effects on diet are still unresolved. In this study, the effects of CCK on food intake in transgenic mice were investigated.</p><p><b>METHODS</b>Transgenic mice were created by microinjection of the PDGF-CCK construct into male pronucleus of the zygotes. The genomic phonetype of transgenic mice were identified by PCR. The expression of PDGF-CCK was analyzed by Western blotting. Body weight, plasma glucose, cholesterol and triglycerides were assayed and analyzed.</p><p><b>RESULTS</b>Two PDGF-CCK transgenic independent lines were established and exhibited a high-levels brain-specific transgene expression compared with that of nontransgenic littermate controls. The food intake of male CCK transgenic mice was decreased by 5% - 10% with the same levels of water consumed compared with wild type mice. The food intake in female mice was not obviously changed. In the transgenic mice the bodyweight was lower and plasma glucose was higher compared with the nontransgenic littermate controls.</p><p><b>CONCLUSIONS</b>The high expression of the CCK gene in the brain can decrease body weight and increase plasma glucose. The differences in food intake between the males and females require further study.</p>

Management of intracranial invasive olfactory neuroblastoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Olfactory neuroblastoma (ONB) is a rare tumor that often arise from the nasal cavity. The aim of this study was to investigate the clinical characteristics and treatments of intracranial invasive ONB.</p><p><b>METHODS</b>Between July 2001 and August 2005, 5 patients with intracranial invasive ONB were treated in our department. Their clinical features, radiological and pathological characteristics, and surgical treatments were analyzed. Among the 5 patients, 1 received transnasal biopsy, and 4 were operated through the transfrontal or extended bifrontal approaches to reconstruct the skull base. After the operation, all the patients received radiotherapy, and one received chemotherapy. They were followed up for 6 to 45 months.</p><p><b>RESULTS</b>The ONB was resected totally in the 4 patients. In all the patients, nasal obstruction was alleviated without cerebrospinal fluid leakage. The visual acuity was improved in 3 patients, who had a decreased visual acuity before the operation. Two patients had metastasis into the lumbosacral spinal canal 6 and 8 months after the operation, one of them received a second operation and the other died.</p><p><b>CONCLUSION</b>ONB has no specific symptoms. Intracranial ONB should be resected as far as possible, and treated by radiotherapy after the operation.</p>

In vivo tracking of bone marrow mesenchymal stem cells labeled with superparamagnetic iron oxide after cerebral ischemia in rats by magnetic resonance imaging / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the feasibility of in vivo tracking of bone marrow mesenchymal stem cells (BMSCs) labeled with superparamagnetic iron oxide (SPIO) by magnetic resonance imaging (MRI) in rats after cerebral ischemia, and to analyze the influence of stem cell therapy on the volume of cerebral infarction.</p><p><b>METHODS</b>The samples of rat bone marrow were collected. BMSCs separated by density gradient centrifugation were cultivated and harvested until the third passage. BMSCs were labeled with SPIO, which was mixed with poly-L-lysine. The labeling efficiency was evaluated by Prussian blue staining. Transient middle cerebral arterial occlusion (MCAO) was performed successfully in 18 adult Sprague-Dawley rats that scored from 6 to 12 by the modified neurological severity test. The 18 rats were then randomly divided into group A, B, and C, with 6 rats in each group and Group C was regarded as control group. BMSCs were injected into the contralateral cortex of ischemia in group A, ipsilateral corpora striata in group B, while D-Hank's solution was injected into ipsilateral corpora striata (group C) 24 hours after MCAO. MRI was performed 1 day after MCAO, 1 day and 14 days after transplantation. The volume of infarcted brain tissue was measured and analyzed. Prussian blue staining of brain tissues was performed to identify the migration of BMSCs.</p><p><b>RESULTS</b>The labeling efficiency of BMSCs with SPIO was 96%. The transplanted BMSCs migrated to the ischemic hemisphere along the corpus callosum and to the border of the infarction, which was confirmed by MRI and Prussian blue staining. The changes of infarction volume were not significantly different among these three groups.</p><p><b>CONCLUSIONS</b>MRI is feasible for in vivo tracking of BMSCs labeled with SPIO in rats. The stem cell therapy may not be able to affect the volume of cerebral infarction.</p>

A case-control study on the risk factors for attempted suicide in patients with major depression / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the environmental risk factors on attempted suicide in patients with major depression, and to study the interaction between factors as single nucleotide polymorphism(SNP) of TPH2 gene rs7305115 associated to attempted suicide in major depression.</p><p><b>METHODS</b>Paired case-control study on 215 suicide attempters with major depression (92 male, 123 female) and molecular biological techniques were used to study the relation between TPH2 gene rs7305115 SNP,interrelated environmental factors and the rate of attempted suicide. Controls were paired with cases according to the same gender, similar age (no more than 3 years) and from the same district.</p><p><b>RESULTS</b>There were remarkably significant differences in gene types and gene frequency between case and control groups (P < 0.001). Data from multivariate conditional logistic regression model analysis showed that hopelessness, negative life-events and family history of suicide were relationship of attempted suicide in patients with major depression with OR values as 0.33 (95% CI: 0.22-0.99), 7.68 (95% CI: 5.79-13.74), 6.64 (95% CI: 2.48-11.04), 2.98 (95% CI: 1.17-5.04) respectively. There was no first level interaction between any of the two risk factors.</p><p><b>CONCLUSION</b>Results from the study supported the idea that hopelessness, negative life-events and family history of suicide were risk factors of attempted suicide in major deprbssion while TPH2 gene rs7305115 A/A might be the protective factor.</p>

Neuronavigation guidance for motor cortex stimulation in resection of gliomas involving the precentral gyrus / 中华显微外科杂志

Objective To explore surgical treatment of gliomas involving the motor eloquent area. Methods Twelve cases of gliomas involving precentral gyrus were underwent awake surgery procedures assis- ted with neuronavigation and brain functional mapping by cortical electrical stimulation.Results Eleven ca- ses acquired accurate location of both lesions and eloquent areas by neuronavigation and direct cortical stimula- tion.7 cases of motor cortices and 2 cases of motor speech centers were confirmed during the operation.Re- section,verified by postoperative MRI,was total in 8 cases (66.7%) and subtotal in 4 patients.Histological examination revealed an infiltrative glioma in all cases (8 low grade astrocytomas,2 high grade astrocytomas and 2 glioblastoma).Four patients had no postoperative deficit,while the other 8 patients were impaired, with,in all cases except one,complete recovery in 7 days to one month.Conclusion Direct cortical elec- trical stimulations and awake surgery offer a reliable,precise and safe method,allowing functional mapping es- pecially useful in case of infiltrative cerebral tumors in eloquent areas.This technique allows improvement in the quality of tumoral resection and concurrently a minimization of the risk of definitive postoperative neurologi- cal deficit.

Effects of Tai Chi Exercise on Somatic Function of Middle-aged Females / 中国康复理论与实践

@#ObjectiveTo investigate the effects of Tai Chi exercise on somatic function of middle-aged females.Methods60 middle-aged females had a 16-week Taichi quan exercise and changes of blood pressure, resting heart rate and vital capacity were tested.ResultsAfter Tai Chi exercise, 60 women had results of resting heart rate and blood pressure decreased, and vital capacity increased obviously (P<0.05～0.01).ConclusionTai Chi exercise maybe an effect sport manner to improve the somatic function of middle-aged females.

Proteomic analysis of hippocampus in the rat / 中国应用生理学杂志

<p><b>AIM</b>To initially analyze the protein expression in the rat hippocampus with the proteomics approach.</p><p><b>METHODS</b>Proteins from hippocampal tissue homogenates of the rat were separated by two-dimensional gel electrophoresis(2-DE), and the proteins were stained with colloidal coomassie blue to produce a high-resolution map of the rat hippocampus proteome. Selected proteins from this map were digested with trypsin, and the resulting tryptic peptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The mass spectrometric data were used to identify the proteins through searches of the NCBI protein sequence database.</p><p><b>RESULTS</b>37 prominent proteins with various functional characteristics were identified. The identification of brain protein classes, like metabolism enzymes, cytoskeleton proteins, heat shock proteins, antioxidant proteins, signalling proteins, proteasome-related proteins, neuron-specific proteins and glial-associated proteins. Furthermore, 3 hypothetical proteins which are unknown proteins, so far only proposed from their nucleic acid structure were identified.</p><p><b>CONCLUSION</b>This study provides the first unbiased characterization of proteins of the rat hippocampus and will be used for future studies of differential protein expression in rat models of neurological disorders.</p>

Recent advance in experimental study of cerebral ischemia treated by vascular endothelial growth factor / 中国医学科学院学报

Vascular endothelial growth factor (VEGF) has been found to be the most powerful angiogenic factor. Studies have shown that cerebral ischemia and hypoxia stimulate the expressions of VEGF and its receptors in the brain, while exogenous VEGF promotes the formation of new blood vessels in the ischemic brain penumbra, and reduce the volume of cerebral infarction. The effect of VEGF on cerebral ischemia was previously explained the mechanism that VEGF had a specific mitogenetic roles in cerebral endothelial cells and thus promoted neovascularization; however recent evidence has shown that VEGF also has direct effects on neural and glial cells. Its multiple protection roles on central nervous system involve vascularization, neurogenesis, direct neurotrophic and neuroprotective effect, as well as antiapoptosis effect, especially when brain ischemia occurs. Further elucidation of these mechanisms on central nervous system may serve as a key procedure in understanding the main aspects of neural repair and neural protection, and develop effective therapeutic measures for intervention in stroke.

Changes in synapses and axons demonstrated by synaptophysin immunohistochemistry following spinal cord compression trauma in the rat and mouse / 生物医学与环境科学（英文）

<p><b>OBJECTIVE AND METHODS</b>To evaluate synaptic changes using synaptophysin immunohistochemstry in rat and mouse, which spinal cords were subjected to graded compression trauma at the level of Th8-9.</p><p><b>RESULTS</b>Normal animals showed numerous fine dots of synaptophysin immunoreactivity in the gray matter. An increase in synaptophysin immunoreactivity was observed in the neuropil and synapses at the surface of motor neurons of the anterior horns in the Th8-9 segments lost immunoreactivity at 4-hour point after trauma. The immunoreactive synapses reappeared around motor neurons at 9-day point. Unexpected accumulation of synaptophysin immunoreactivity occurred in injured axons of the white matter of the compressed spinal cord.</p><p><b>CONCLUSION</b>Synaptic changes were important components of secondary injuries in spinal cord trauma. Loss of synapses on motor neurons may be one of the factors causing motor dysfunction of hind limbs and formation of new synapses may play an important role in recovery of motor function. Synaptophysin immunohistochemistry is also a good tool for studies of axonal swellings in spinal cord injuries.</p>

The experimental study of rAAV2 transfecting neural stem cells-derived neurospheres / 中国应用生理学杂志

<p><b>AIM</b>To investigate the abilities of recombinant adeno-associated virus type 2 (rAAV2) transfecting neurospheres.</p><p><b>METHODS</b>The rAAV2 conjugated with FITC (rAAV2-FITC) was added into the culture medium of neurospheres and 30 minutes later the neurospheres were detected with a fluorescence microscopy to determine if the AAV can combine with neurospheres. The rAAV2 containing GFP reporter gene (rAAV2-GFP) was incubated with the neurospheres for a month and then detected the ability of transfecting neurospheres. The neurospheres transfected with rAAV2-containing GFP were transplanted to the brain of rats. A month later the rats were sacrificed and the brains were removed to detect if there are expressions of the reporter gene. The neurospheres were transfected with rAAV2 containing hypoxia responds elements (HRE) and vascular endothelium growth factor(VEGF) gene and reporter gene GFP (rAAV2-HRE-VEGF-GFP) and then cultured in low oxygen density environments. Seventy-two hours later the neurospheres were detected through a fluorescence microscopy.</p><p><b>RESULTS</b>The neurospheres incubated with rAAV2-FITC present bright green fluorescence. GFP, the reporter gene, can be seen clearly 1 month after being transfected with rAAV2-GFP. The same green fluorescence protein can be observed ex vivo as well. The fluorescence can be seen in neurospheres transfected by rAAV2-HREVEGF-GFP only in low oxygen density.</p><p><b>CONCLUSION</b>The rAAV2 can transfect neurospheres specifically and efficiently. Reporter gene can be expressed in the neurospheres in vivo and ex vivo. Expression of reporter gene can be adjusted by HRE.</p>

Experimental study on the proliferation and plasticity of neural stem cells in situ in adult rats after cerebral infarction / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the proliferation and plasticity of neural stem cells in situ in adult rats after cerebral infarction.</p><p><b>METHODS</b>Cerebral infarction models of rats were made and the dynamic expression of bromodeoxyuridine (BrdU) and BrdU/polysialylated neural cell adhesion molecule (PSA-NCAM) were determined by immunohistochemistry and immunofluorescence staining.</p><p><b>RESULTS</b>Compared with the controls, the number of BrdU-positive cells in the subventricular zone (SVZ) and hippocampus increased strikingly at day 1 (P < 0.05), reached maximum at day 7, and decreased markedly at day 14, but it was still elevated compared with that of the controls (P < 0.05); The number of BrdU-labeled with PSA-NCAM-positive cells increased strikingly at day 7 (P < 0.05), reached maximum at day 14, and markedly decreased at day 28, but it was still elevated compared with that of the controls (P < 0.05), and was equal to 60% of the number of BrdU-positive cells in the same period.</p><p><b>CONCLUSIONS</b>Our results indicate that cerebral infarction stimulate the proliferation of inherent neural stem cells in situ and most proliferated neural stem cells represent neural plasticity.</p>