The risk of stroke increases significantly after transient ischemic attack (TIA). TIA is an independent risk factor for cerebral infarction. This article review s the advances in prediction models of stroke risk after TIA in order to conduct rapid and accurate risk assessment and stratification in patients w ith TIA and develop timely reasonable treatment strategies, thereby reducing the risk of stroke.

Objective To observe the influences of VEGF transfection on the proliferation and ultrastructure of hBMSCs. Methods Three groups were enrolled in the experiment: group of Ad-VEGF transfection, group of empty Ad transfection, and the control group. Cells were observed continually by inverted phase contrast microscope, and stained by HE. Proliferation of cells was tested by MTT and by flow cytometry analysis. Results Histological observation and observation through inverted phase contrast microscope showed that the cells were of the similar morphology in the 3 groups. As time elapsed, the amount of cells increased, but still no obvious differences were found in optical density (OD) value of hBMSCs.Groups B, C, A had a similar percentage of DNA G1 period and a similar proliferation index (PrI) ( P >0. 05). Conclusion Transfeetion of VEGF has no obvious influence on the prohferation and morphologyof hBMSCs in vitro.

Restriction endonucleases are important molecular biology tools for DNA recombination.Because of the cleavage of DNA,their recombinant expression is difficult with low yields and complicated purification processes.In commercial productions,the technology that uses specific methylases to protect host DNA from digestion of the expressed restriction enzymes was cumbersome and practically limited.For solving this problem the expression of restriction enzyme Not Ⅰ was performed by using the DNA methylase M.Sss Ⅰ derived from Spiroplasma sp.MQ1 which specifically kept CpG sequence methylated.The methylated DNA was protected from the cutting of Not Ⅰ whose recognition sequence contained CpG.The gene of methylase M.Sss Ⅰ was introduced into Escherichia coli ER2566 and constitutively expressed,resulting in the CpG methylation pattern of the host DNA.Restriction enzyme Not Ⅰ was successfully expressed in this E.coli strain.Furthermore,by adding a purification tag to one terminus of the enzyme,recombinant Not Ⅰ was prepared as a highly purified and active product through two simple Ni-affinity and anion exchange chromatography steps.This expression system can be applied for the preparation of a series of restriction enzymes with CpG in their recognition sequences.

To obtain active hFKBP52 protein for screening novel neu rotrophic drugs. Semi-nested and overlap PCR and affinity chromatography were u sed. hFKBP52 gene was cloned successfully from human fetal brain cDNA library, a nd then highly expressed (about 30%) as fusion protein in pET28a(+) vector syste m. The recombinant protein was purified as one band on SDS-PAGE. The purified h FKBP52 showed peptidyl-prolyl cis-trans isomerase (PPIase) activity, simil ar to the wild type.

Rhesus retinal vascular endothelial cell line RF/6A cells were treated with human insulin. Cell proliferation, migration, and lumen formation, as well as the expressions of vascular endothelial growth factor-A ( VEGF-A ), VEGF-A receptors, and phosphorylated receptors were measured. Insulin promoted RF/6A cell proliferation, migration, and lumen formation ( all P＜0. 01 ). Insulin increased the expression of VEGF-A mRNA and improved its protein activity ( all P＜0. 05 ), and promoted the expression of VEGFR2 mRNA and its phosphorylation ( both P＜0. 01 ). There was no significant difference in the expression of VEGFR1 mRNA among the groups ( P＞0. 05 ).

Japanese encephalitis virus (JEV) is a single-stranded and positive-sense RNA, which has a single ORF (open reading frame), encoding a polyprotein precursor. Non-structural protein 3 (NS3) plays an important role in processing the polyprotein precursor and has become an important drug target of flavivirus. In this study, NS2BH-NS3 gene was amplified by PCR and subcloned to the prokaryotic expression plasmid, resulting pET30a-NS2BH-NS3. The fusion protein was expressed in Escherichia coli BL21 (DE3) in soluble form after induction by Isopropyl beta-D-1-Thiogalactopyranoside (IPTG). The recombinant protein was purified by Ni-NTA affinity column. Then a fluorescence resonance energy transfer (FRET) method was used to determine enzymatic activity and the assay conditions were optimized. After screening 113 compounds, we found two compounds inhibiting the activity of NS2BH-NS3. This study provides a convenient and cost-effective method for screening of JEV NS3 protease inhibitor.
Encephalitis Virus, Japanese ; enzymology ; Escherichia coli ; metabolism ; High-Throughput Screening Assays ; Protease Inhibitors ; chemistry ; RNA Helicases ; metabolism ; Recombinant Fusion Proteins ; metabolism ; Serine Endopeptidases ; metabolism ; Viral Nonstructural Proteins ; metabolism

In this paper, the chloroplast psbK-psbI intergenic spacers of 18 species of Dendrobium and their adulterants were amplified and sequenced, and then the sequence characteristics were analyzed. The sequence lengths of chloroplast psbK-psbI regions of Dendrobium ranged from 474 to 513 bp and the GC contents were 25.4%-27.6%. The variable sites were 71 while the informative sites were 46. The inter-specific genetic distances calculated by Kimura 2-parameter (K2P) of Dendrobium were 0.006 1-0.058 1, with an average of 0.028 4. The K2P genetic distances between Dendrobium species and Bulbophyllum odoratissimum were 0.093 2-0.120 4. The NJ tree showed that the Dendrobium species can be easily differentiated from each other and 6 samples of the inspected Dendrobium species were identified successfully through sequencing the psbK-psbI intergenic spacer. Therefore, the chloroplast psbK-psbI intergenic spacer can be used as a candidate marker to identify Dendrobium species and its adulterants.

The mitogen activated protein kinases-extracellular signal regulated kinases (MAPK-ERK) pathway is involved in regulation of multiple cellular processes including the cell cycle.In the present study using a Huh7 cell line Con1 with an HCV replicon,we have shown that the MAPK-ERK pathway plays a significant role in the modulation of HCV replication and protein expression and might influence IFN-α signalling.Epithelial growth factor (EGF) was able to stimulate ERK activation and decreased HCV RNA load while a MAPK-ERK pathway inhibitor U0126 led to an elevated HCV RNA load and higher NS5A protein amounts in Con1 cells.It could be further demonstrated that the inhibition of the MAPK-ERK pathway facilitated the translation directed by the HCV internal ribosome entry site.Consistently,a U0126 treatment enhanced activity of the HCV reporter replicon in transient transfection assays.Thus,the MAPK-ERK pathway plays an important role in the regulation of HCV gene expression and replication.In addition,cyclin-dependent kinases (CDKs) downstream of ERK may also be involved in the modulation of HCV replication since roscovitine,an inhibitor of CDKs had a similar effect to that of U0126.Modulation of the cell cycle progression by cell cycle inhibitor or RNAi resulted consistently in changes of HCV RNA levels.Further,the replication of HCV replicon in Conl cells was inhibited by IFN-α.The inhibitory effect of IFN-α could be partly reversed by pre-incubation of Con-1 cells with inhibitors of the MAPK-ERK pathway and CDKs.It could be shown that the MAPK-ERK inhibitors are able to partially modulate the expression of interferon-stimulated genes.

Objective To investigate the effects of heat-killed Staphylococcus aureus (HKSA) on the apoptosis and expression of iNOS and IL-1β in THP-1 monocytes in the presence of high concentration of glucose.Methods THP-1 cells were cultured in medium containing 25.0 mmol/L(HG) or 5.5 mmol/L (LG,control) D-glucose for 12 h-8 d.The THP-1 cells cultured for 6 d were extracted on the 0-48 h with or without HKSA,then apoptosis and expression of iNOS and IL-1β were examined.Apoptosis was analyzed by flow cytometry and expressions of IL-1β and iNOS were quantitated by real-time PCR.Results The expression of iNOS and IL-1β in THP-1 monocytes was increased significantly in the presence of high concentration of glucose for 12-48 h(P＜0.05),reaching the highest level at 24 h and returned to baseline after 4 d.The expression was significantly lower than that of control after 4-6 d.Apoptosis rate was also increased significantly after 48 h to 4 days.HKSA infection enhanced apoptosis,but inhibited the expression of iNOS and IL-1 β in the presence of high concentration of glucose.The expression of iNOS and IL-1β increased significantly at 6 h(P＜0.01),reaching the highest level at 12 h,but the levels were significantly lower than those in control groups (P＜0.05).Conclusion These data suggest that high concentration of glucose can interfere with the anti-bacterial function of monocytes by reducing their expression of iNOS and IL-1β and enhancing their apoptosis.

Objective　To observe the effects of residual perfluorocarbon liquid(PFCL) droplets in the anterior chamber in patients after vitreoretinal(VR) surgery for complicated retinal detachments.Methods　The study group consisted of nine patients(nine eyes)aged 16～64 in whom droplets of perfluorodeclin liquid(PFDL) appeared in the anterior chamber subsequent to VR surgery for complicated retinal detachments involving scleral bucking, vitrectomy and/or lensectomy, the peeling of pre-retinal membrane, perfluorodecalin injection, and perfluorodeclin liquid-silicone oil or fluid-air exchange. Mean follow-up was 10.3 months.Results　Three to 30 droplets of perfluorodeclin liquid were found in the anterior chambers in 9 eyes. There was no corneal complication or inflammatory reactions or blood vessel invasion into the corneal stroma or increased intraocular pressure.Conclusion　Residual perfluorodeclin liquid droplets in the anterior chamber are well tolerated and do not induce corneal damage or ocular inflammation.