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Objective: To summarize the diagnosis and treatment of pulmonary thromboembolism (PTE) in post-operative neurosurgical patients., Methods: 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., Results: 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., Conclusions: 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. more...

Objective: 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., Methods: 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., Results: 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., Conclusions: 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. more...

Objective: To explore the gene transfer efficiencies and different cell tropism of recombinant adeno-associated virus 1 (rAAV1), rAAV 2, and rAAV 5 in the hippocampus of adult rats, and select more suitable gene vectors for central nervous system (CNS) gene therapy., Methods: Eighteen SD male adult rat were divided into 3 groups randomly (n = 6), with every group being injected with the titre and volume matched rAAV1, rAAV2, and rAAV5 vectors. All these vectors contained enhanced green fluorescent protein (EGFP) sequences as a reporter gene. Animals were killed after 8 weeks. The coronal cryosections of brains were processed, and the EGFP gene expression was observed with fluorescence microscopy; the expression area and the number of EGFP positive cells were automatically measured using Image-Pro Plus 4.5 software. To identify their cell tropism in the CNS, the sections were counterstained with neuronal marker neuron-specific nuclear protein (NeuN) and the astrocyte marker glial fibrillary acidic protein (GFAP) and were examined with a confocal laser scanning microscope., Results: Eight weeks after adeno-associated virus gene transfer, the expression profile of EGFP demonstrated significant difference. Most of the pyramidal cell layers of CA1 to CA3 area and granular cell of dent gyrus were strongly transduced by rAAV1; whereas rAAV2 primarily transduced the cells of multiform layer in hilar region of the dentate gyrus; only a few pyramidal cells were transduced by rAAV5. Moreover, rAAV1 showed significantly wider distribution throughout the hippocampus, and the quantity of EGFP positive cells and the EGFP positive area were significantly more than those of rAAV2 and rAAV5 (P < 0.01). The counterstaining for NeuN and GFAP showed that rAAV1 was able to transduce both neurons and glia cells, whereas rAAV2 and rAAV5 transduced the neurons only., Conclusion: rAAV1 is an excellent transgene vector with higher efficiency and broader cell tropism in the CNS. more...

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. more...

Objective: To investigate the proliferation and plasticity of neural stem cells in situ in adult rats after cerebral infarction., Methods: 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., Results: 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., Conclusions: 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. more...

Objective: To investigate the value of measuring the concentration of soluble CD44 splice variant 6 (sCD44v6) in peripheral blood in patients with invasive and non-invasive pituitary adenomas., Methods: The concentrations of sCD44v6 in peripheral blood were measured with ELISA in 68 patients with invasive pituitary adenomas and 100 patients with non-invasive pituitary adenomas., Results: The serum concentration of sCD44v6 in patients with invasive pituitary adenomas was lower than that in patients with non-invasive pituitary adenomas, while the latter was lower than that in healthy controls. The serum concentrations of sCD44v6 were (44.63 +/- 7.21), (34.53 +/- 6.41), and (26.34 +/- 4.95) ng/ml in patients with invasive microadenoma, macroadenoma, and giant adenoma, and (60.78 +/- 9.61), (57.78 +/- 10.00), and (37.22 +/- 5.17) ng/ml in patients with non-invasive microadenoma, macroadenoma, and giant adenoma, lower than that in the healthy control group (68.73 +/- 6.00) ng/ml. Significant differences were observed among groups (P < 0.005). The concentration of sCD44v6 in peripheral blood decreased as the tumor size increased (P < 0.01), which was particularly significant in invasive pituitary adenomas. The positive rate in the patients with invasive pituitary adenomas reached 89.71%., Conclusion: Serum concentration of sCD44v6 in the peripheral blood is inversely correlated with tumor size and its invasive growth, which may provide certain value in the early diagnosis, treatment and prognosis of invasive pituitary macroadenoma and giant adenoma. more...

Objective: To clone a novel gene relative to blood glucose regulation., Methods: Rat modes of autonomous regulation of blood glucose was made by intra jugular vein to right atrium injection of high concentration of glucose solution, and the control rats were injected with 0.9%NaCl both before skeletal muscles were separated for gene analysis. The differentially expressed fragments were identified by differential display technology (DDRT-PCR). After slot blot and Northern blot analysis, the artificial positive fragments were excluded and the true EST (expression sequence tag) differentially expressed was obtained. These positive EST were used as probes to screen cDNA library of rat skeletal muscle., Results: A novel full-length cDNA, named as Fang-2 was obtained. GenBank Accession No. was AF399874. Fang-2 was found rat homologue of human troponin T by blast software (NCBI). It shared 78% identical nucleotides, which showed the family proteins were conservative. After high concentration of glucose stimulation of rats, the expression of Fang-2 was down-regulated., Conclusions: A novel gene relative to blood glucose regulation was cloned from rat skeletal muscle. The gene can regulate blood glucose level by effect certain mechanisms unknown yet with down-regulation expression. more...