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991.
The generation of induced neuronal cells from human bone marrow stromal stem cells (hBMSCs) provides new avenues for basic research and potential transplantation therapies for nerve injury and neurological disorders. However, clinical application must seriously consider the risk of tumor formation by hBMSCs, neural differentiation efficiency and biofunctions resembling neurons. Here, we co-cultured hBMSCs exposed to retinoic acid (RA) with human olfactory ensheathing cells (hOECs) to stimulate its differentiation into neural cells, and found that hBMSCs following 1 and 2 weeks of stimulation promptly lost their immunophenotypical profiles, and gradually acquired neural cell characteristics, as shown by a remarkable up-regulation of expression of neural-specific markers (Tuj-1, GFAP and Galc) and down-regulation of typical hBMSCs markers (CD44 and CD90), as well as a rapid morphological change. Concomitantly, in addition to a drastic decrease in the number of BrdU incorporated cells, there was a more elevated synapse formation (a hallmark for functional neurons) in the differentiated hBMSCs. Compared with OECs alone, this specific combination of RA and hOECs was significantly potentiated neuronal differentiation of hBMSCs. The results suggest that RA can enhance and orchestrate hOECs to neural differentiation of hBMSCs. Therefore, these findings may provide an alternative strategy for the repair of traumatic nerve injury and neurological diseases with application of the optimal combination of RA and OECs for neuronal differentiation of hBMSCs.  相似文献   
992.
Previous studies addressing the protection of tea polyphenols against cerebral ischemia/ reperfusion injury often use focal cerebral ischemia models, and the optimal dose is not unified. In this experiment, a cerebral ischemia/reperfusion injury rat model was established using a modified four-vessel occlusion method. Rats were treated with different doses of tea polyphenols (25, 50, 100, 150, 200 mg/kg) via intraperitoneal injection. Results showed that after 2, 6, 12, 24, 48 and 72 hours of reperfusion, peroxide dismutase activity and total antioxidant capacity in brain tissue gradually increased, while malondialdehyde content gradually decreased after tea polyphenol intervention. Tea polyphenols at 200 mg/kg resulted in the most apparent changes. Terminal deoxynucleotidyl transferase-mediated nick end labeling and flow cytometry showed that 200 mg/kg tea polyphenols significantly reduced the number and percentage of apoptotic cells in the hippocampal CA1 region of rats after cerebral ischemia/reperfusion injury. The open field test and elevated plus maze experiments showed that tea polyphenols at 200 mg/kg strengthened exploratory behavior and reduced anxiety of cerebral ischemia/reperfusion injured rats. Experimental findings indicate that tea polyphenols protected rats against cerebral ischemia/ reperfusion injury and 200 mg/kg is regarded as the optimal dose.  相似文献   
993.
In our previous studies, we showed that frontal lobe and brainstem functions were abnormal in online game addicts. In this study, 14 students with Internet addiction disorder and 14 matched healthy controls underwent proton-magnetic resonance spectroscopy to measure cerebral function. Results demonstrated that the ratio of N-acetylaspartate to creatine decreased, but the ratio of cho- line-containing compounds to creatine increased in the bilateral frontal lobe white matter in people with Internet addiction disorder. However, these ratios were mostly unaltered in the brainstem, suggesting that frontal lobe function decreases in people with Internet addiction disorder.  相似文献   
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Ninety-four patients with lumbar intervertebral disc herniation were enrolled in this study. Of these, 48 were treated with Feng’s Spinal Manipulation, hot fomentation, and bed rest (treatment group). The remaining 46 patients were treated with hot fomentation and bed rest only (control group). After 3 weeks of treatment, clinical parameters including the angle of straight-leg raising, visual analogue scale pain score, and Japanese Orthopaedic Association score for low back pain were improved. The treatment group had significantly better improvement in scores than the control group. Magnetic resonance myelography three-dimensional reconstruction imaging of the vertebral canal demonstrated that filling of the compressed nerve root sleeve with cerebrospinal fluid increased significantly in the treatment group. The diameter of the nerve root sleeve was significantly larger in the treatment group than in the control group. However, the sagittal diameter index of the herniated nucleus pulposus and the angle between the nerve root sleeve and the thecal sac did not change significantly in either the treatment or control groups. The effectiveness of Feng’s Spinal Manipulation for the treatment of symptoms associated with lumbar intervertebral disc herniation may be attributable to the relief of nerve root compression, without affecting the herniated nucleus pulposus or changing the morphology or position of the nerve root.  相似文献   
997.

Background

Drug-metabolizing enzymes (DMEs) inhibition based drug-drug interaction and herb-drug interaction severely challenge the R&D process of drugs or herbal ingredients.

Objective

To evaluate the inhibition potential of wogonin (an important flavonoid isolated from the root of Scutellaria baicalensis) towards one of the most important phase II DMEs, UDP-glucuronosyltransferase (UGT) 1A9.

Methods

Both recombinant UGT1A9-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and human liver microsomes (HLMs)-catalyzed propofol glucuronidation reaction were used as two different probe reactions.

Results

Wogonin noncompetitively inhibited recombinant UGT1A9-catalyzed 4-MU glucuronidation, and exerted competitive inhibition towards HLMs-catalyzed propofol glucuronidation. The inhibition kinetic parameters (Ki) were calculated to be 3.2 µM and 52.0µM, respectively.

Conclusion

Necessary monitoring was needed when wogonin was co-administered with the clinical drugs mainly undergoing UGT1A9-mediated glucuronidation elimination. Additionally, probe reactions-dependent inhibition of wogonin towards the activity of UGT1A9 should be paid attention when translating these in vitro data into in vivo situation.  相似文献   
998.
MicroRNA-34a(miR-34a), a pivotal member of the p53 network, was found to be down-regulated in multiple types of tumors and further reported as a tumor suppressor microRNA. However, the profile and biological effects of miR-34a in breast cancer are still unclear. In this study, we aimed to determine the effect of miR-34a on the growth of breast cancer and to investigate whether its effect is achieved by targeting Bcl-2 and SIRT1. We examined miR-34a levels in breast cancer cell lines and breast cancer specimens by qRT-PCR. Proliferation assay, apoptosis assay, and morphological monitoring were performed to assess the tumor suppression effect of miR-34a in breast cancer cell lines. Western blotting was used to identify the targets of miR-34a. We also investigated the anti-tumor effects of the treatment combining miR-34a with 5-FU in breast cancer cells. We found that miR-34a expression was down-regulated in 5 breast cancer cell lines compared with the immortalized normal mammary epithelial cell line 184A1, and was also down-regulated by almost 50 % in breast cancer samples compared with their corresponding adjacent non-malignant breast tissues. Ectopic restoration of miR-34a in breast cancer cells suppressed cells proliferation, invasion, and induced apoptosis. Bcl-2 and SIRT1 as the targets of miR-34a were found to be in reverse correlation with ectopic expression of miR-34a. Furthermore, the treatment combining miR-34a with 5-FU significantly showed more efficient anti-tumor effects than single treatment of miR-34a or 5-FU. Since miR-34a functions as tumor suppressor microRNA in breast cancer, modulating miR-34a level in breast cancer was suggested to be a new and useful approach of breast cancer therapy.  相似文献   
999.
Huang ZW  Fan ZX  Sun JT  Li WM  Gao YQ  Quan YH  Geng YM  Niu YY  Wu BX 《Heart and vessels》2012,27(6):603-609
We investigated the short-term and medium-term results in patients with pulmonary arterial hypertension (PAH) associated with atrial septal defect (ASD) undergoing transcatheter closure. Fifteen patients with severe PAH associated with ASD who underwent successful occluder implantation from 2007 to 2010 were included. Clinical, echocardiographic, and hemodynamic data were reviewed. Severe PAH was defined as pulmonary arterial systolic pressure measured by catheterization was ≥60 mmHg and pulmonary vascular resistance (PVR) ≥6 Wood Units (WU). Compared with baseline, the 6-minwalking distance significantly increased by 29.7 ± 26.3 m (P < 0.001) at 3 months (short-term) and 65.4 ± 63.6 m (P < 0.001) at 23.4 ± 9.7 months (medium-term), World Health Organization function class considerably improved after postclosure short-term and medium-term. Repeat cardiac catheterization (n = 7) showed that mean pulmonary arterial pressure decreased from 51.6 ± 9.4 mmHg at baseline to 21.0 ± 3.8 mmHg (P < 0.001) at follow-up of 12 months. The PVR decreased by 5.6 ± 1.1 WU (P < 0.001). Through carefully selected patients with severe PAH associated with ASD, transcatheter closure can be safely performed with a promising short-term and medium-term outcome. Trial occlusion is an effective way for deciding the reversibility of severe PAH in ASD patients. The role of aerosolized iloprost for pulmonary vasoreactivity testing in patients with severe PAH secondary to ASD requires further investigation.  相似文献   
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