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Wei Jin

Publications and source records attributed to Wei Jin.

At least 37 records · Page 2Linked to original sources
PubMed2006

[Determination of trace germanium by HG-ICP and study on the medium influence].

A method to determine the content of trace germanium by hydride generation inductively coupled plasma atomic emission spectrometry was established. The influences of different acidic medium, concentration of NaBH4 and other concomitant elements are examined systemically. The optimal analytical conditions were discussed and examined. The detection limit is 0.2 ng x mL(-1) and the precision is 0.9%. The value of germanium content detected in environmental reference material agrees with the certified value. The medium influence on determining trace germanium was studied in detail.

English Abstract↗
PubMed2005

Preparative isolation and purification of trans-3,5,4'-trihydroxystilbene-4'-O-beta-D-glucopyranoside and (+)catechin from Rheum tanguticum Maxim. ex Balf. using high-speed counter-current chromatography by stepwise elution and stepwise increasing the flow-rate of the mobile phase.

Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of trans-3,5,4'-trihydroxystilbene-4'-O-beta-D-glucopyranoside (compound 1) and (+)catechin (compound 2) from Rheum tanguticum Maxim. ex Balf. by stepwise elution with a pair of two-phase solvent system composed of ethyl acetate-ethanol-water (25:1:25, v/v) and (5:1:5, v/v), and stepwise increasing the flow-rate of the mobile phase from 0.8 to 2.0 mlmin(-1) after 5 h. The preparative HSCCC separation was performed on 250 mg of crude extract yielding pure compound 1 (10.2 mg) and compound 2 (26.7 mg) all at purities of over 96% in a single run. The structures of the two compounds have been elucidated by means of spectroscopic methods including MS and 1H, 13C nuclear magnetic resonance spectroscopy.

Catechin↗
PubMed2005

Generation of continuously wavelength-tunable optical short pulses by use of two self-seeded Fabry-Perot laser diodes and an optical switch.

Generation of wavelength-tunable optical short pulses by use of two self-seeded Fabry-Perot laser diodes in a parallel configuration is described. The system supports continuous wavelength tuning in a relatively wide range of 42 nm. The side-mode suppression ratio achieved is 35 dB across the entire wavelength tuning range. The system is convenient for continuous wavelength tuning.

Journal Article↗
PubMed2005

[Therapeutic neovascularization with autologous bone marrow CD34+ cells transplantation in hindlimb ischemia].

OBJECTIVE: To explore whether transplantation of autologous bone marrow stem cells might augment angiogenesis and collateral vessel formation in a canine model of hindlimb ischemia. METHODS: CD34(+) stem cells were centrifugation through Ficoll and an immune magnetic cell sorting system from bone marrow (20 ml) of canine (n = 5) and induced into endothelial cells with VEGF in vitro, and expression of von Willebrand factor. Bilateral hindlimb ischemia was surgically induced in canines and Dil fluorescence labeled autologous stem cells were transplanted into the ischemic tissues. RESULTS: Four weeks after transplantation, fluorescence microscopy revealed that transplanted cells were incorporated into the capillary network among preserved skeletal myocytes. The stem cells transplanted group had more angiographically detectable collateral vessels, a higher capillary density (12.0 +/- 2.8 vs. 5.0 +/- 1.6 per field; t = 4.17 P < 0.05) and a higher ABI (0.58 +/- 0.14 vs. 0.32 +/- 0.11; t = 2.95, P < 0.05). CONCLUSIONS: Direct local transplantation of autologous bone marrow CD34(+) stem cells seems to be a useful strategy for therapeutic neovascularization in ischemic tissues in adults, consistent with "therapeutic vasculogenesis."

Animals↗
PubMed2005

Efficient target strategies for contagion in scale-free networks.

Organizations or individuals often have an incentive to target a certain number of agents to launch a contagion process effectively and efficiently, for example, sampling consumers in the diffusion of new products. We present an effective strategy for contagion in scale-free networks. The proposed strategy, hub strategy, calls for targeting mostly the highly connected nodes. The biased level implemented in this strategy characterizes its ability to identify hub nodes. We demonstrate that hub strategy can improve the contagion effects evidently. We find that biased level increases first with heterogeneity level of contagion network but decreases with that after a certain value, and decreases with initial adopter rate all the time. Moreover, degree correlations in contagion networks may reduce biased level.

Journal Article↗
PubMed2005

[Treatment of the infrequent complications after stent graft placement for aortic disease].

OBJECTIVE: To explore the infrequent complications and treatment after endoluminal stent graft implantation for aortic diseases. METHODS: Review of the characters and complications for five cases of aortic diseases by stent graft implantation. RESULTS: The complications of 4 cases have been relieved by operation or re-stent implantation, 1 case was died. CONCLUSION: The complications are difficult to forecast for stent graft placement in aortic diseases, the surgeon should be well practiced in surgical and interventional technique, so as to treat the complications in time.

Aged↗
PubMed2005

Improved cryopreservation of human embryonic stem cells with trehalose.

Human embryonic stem (ES) cells have been established either from fresh or frozen embryos. The recovery rates of undifferentiated human ES cells after cryopreservation with conventional slow-rate freezing and rapid-thawing methods are relatively low. The purpose of this study was to improve cryopreservation efficiency by modifying conventional methods with addition of trehalose. Immature oocytes donated from patients undergoing IVF treatment were utilized to generate blastocysts. One human ES cell line (named hES1) was established and characterized in detail. The hES1 cells expressed regular human ES cell markers, including stage-specific embryonic antigens SSEA-3, SSEA-4, tumour rejection antigens TRA-1-60, TRA-1-81 and octamer-binding transcription factor Oct-4 with high levels of alkaline phosphatase and telomerase activities. Cells could be differentiated to form teratomas in vivo. With slow-rate freezing and rapid-thawing methods modified by adding trehalose, the recovery rate of undifferentiated hES1 cells has been greatly improved from 15 to 48%. Cells retained pluripotency with normal karyotype after thawing. The results indicated that the use of trehalose is efficient and convenient for cryopreservation of human ES cells.

Animals↗
PubMed2005

[Apoptotic characteristics of spleen lymphocyte in mice irradiated by lethal dose and its relationship to the expression of Bax and Bcl-XL proteins].

OBJECTIVE: To observe the apoptotic characteristics of mouse spleen lymphocyte after lethal dose gamma-irradiation and its relationship to the expression of Bax and Bcl-XL proteins. METHODS: Two hundred and twenty-five second-grade C57 mice were randomly divided into six groups of 0, 6, 9, 12, 15 and 20 Gy. They were sacrificed by dislocation and samples were taken on 1-28 days after whole body single gamma-irradiation. Lymphocyte apoptosis and necrosis were analyzed by TdT-mediated dUTP nick end labeling (TUNEL) and flow cytometry (FCM) techniques. The expression of Bax and Bcl-XL proteins were estimated by immunohistochemical method. RESULTS: (1) The number of peripheral white blood cells of mice increased temporarily at 6 hours after radiation, thereafter, began to decrease rapidly, which reached the minimum on day 7 and recovered normal level basically one month after 6 Gy gamma-irradiation. (2) Apoptotic rate of spleen lymphocytes increased significantly, peaking at 6 hours after radiation, which was found to have a dose-response relationship during 6-24 hours after < or =12 Gy irradiation, but decreased after > or =15 Gy irradiation. (3) It was confirmed by FCM that the apoptotic rate of spleen lymphocytes increased along with the elevation of radiation dose. However, the apoptotic rate began to decrease and the necrotic rate rose distinctively after > or =15 Gy irradiation. The analysis of DNA gel electrophoresis supported above-mentioned results. (4) The expression of Bax protein in spleen lymphocyte enhanced at 6 hours after 6 Gy gamma-irradiation and peaked by 12 Gy-irradiation, showing a dose-dependent pattern, but which was not be found after > or =15 Gy gamma-irradiation. On the other hand, the expression of Bcl-XL protein reduced persistently with the increase of radiation dose, and also presented a better dose-dependent effect after < or =12 Gy irradiation. CONCLUSION: After 6-12 Gy gamma-irradiation, the apoptosis is the major death way of spleen lymphocyte, while both necrosis and apoptosis are important death pathways after > or =15 Gy irradiation. Pro-apoptotic Bax and anti-apoptotic Bcl-XL play an important role in the apoptotic regulation of spleen lymphocytes induced by lethal dose radiation.

Animals↗
PubMed2005

Improving the visual realism of virtual surgery.

In this work we focus our attention on improving the visual realism of virtual surgery. A synthetic solution by innovative use of various image-based rendering methods is presented for realistic rendering of virtual surgery scenes. We have, for the first time, developed a methodology for generating virtual surgery scenes with realistic glistening effects by a combination of various image-based rendering techniques, including image mosaicing and view-dependent texture mapping. Realistic examples are presented to showcase the results.

Computer Simulation↗
PubMed2005

Highly efficient transformation and plant regeneration of tall fescue mediated by Agrobacterium tumefaciens.

An efficient and reproducible system has been developed for the production of transgenic plants in tall fescue (Festuca arundinacea Schreb.) using A. tumefaciens-mediated transformation. Two-months-old suspension cultures served as excellent explants for transformation. The explants were inoculated with an A. tumefaciens strain EHA105 carrying a plasmid pDBA121 containing genes for hygromycin phosphotransferase (hpt) and phosphinotricin acetyltransferase (bar). The commercial herbicide Basta was used as a selective agent. Inclusion of acetosyringone (ACS) 20 mg/L in the co-culture medium led to an increase in transformation efficiency. The efficiency of transformation was highly dependent on the genotype, the explant, the culture medium and selective agent used. Tall fescue transformation efficiency is 2.85-10.9 plants per gram fresh weight (FW) of suspension cultures. This is much higher than the corresponding values reported before (2-5 plants). So far more than 300 transgenic plants have been obtained, the fertility of some transgenic plants had decreased. Stable integration and high expression of the transgenes were confirmed by PCR analysis and Southern blot hybridization or herbicide Basta spraying test.

Agrobacterium tumefaciens↗
PubMed2005

[Immediate effect of cardiac resynchronization therapy by tissue synchronization imaging and tissue tracking in patients with congestive heart failure].

OBJECTIVE: To evaluate the immediate effect of cardiac resynchronization therapy (CRT) by Doppler tissue imaging (DTI), tissue synchronization imaging (TSI) and tissue tracking imaging (TTI) in patients with congestive heart failure. METHODS: Ten patients with congestive heart failure who had cardiac resynchronization therapy were enrolled. The TSI and TTI imaging were performed by GE vivid 7 with M3s probe. The TTI image was obtained in diastole to determine delayed longitude contraction (DLC). The left ventricular ejection fraction (LVEF), the percentage of delayed longitude contraction segments (DLC), the standard deviation of the time to peak myocardial systolic contraction of 16 segments (Ts-SD), the standard deviation of the time to peak myocardial diastole of 16 segments (Td-SD), the systolic velocity of right ventricule (RV-Sm) and the average systolic velocity of mitral valve annulus (LV-Sm) were measured. The intraventricular dyssynchrony could be semi-quantified by TSI as 4 (red), 3 (orange), 2 (yellow), 1 (green), and the average value of 16 segments was defined as the TSI index. The immediate changes of these parameters were investigated when the pacemaker was turned on and off. The correlation of the Ts and TSI index was also analyzed. RESULTS: When the pacemaker was on, the LVEF improved significantly from (37 +/- 11.30)% to (46 +/- 10.10)% (P < 0.01), and LV-Sm increased significantly from (3.16 +/- 0.87) cm/s to (3.76 +/- 0.74) cm/s (P < 0.01), RV-Sm increased significantly from (6.79 +/- 1.78) cm/s to (7.75 +/- 1.92) cm/s (P < 0.01). DLCs decreased significantly from (35 +/- 6.04)% to (18.13 +/- 9.97)% (P < 0.01), Ts-SD decreased from (83.97 +/- 33.02) ms to (52.67 +/- 19.65) ms, P < 0.05, Td-SD decreased from (87.81 +/- 22.34) ms to (63.45 +/- 31.49) ms, P < 0.05 and TSI index reduced from 2.11 +/- 0.15 to 1.60 +/- 0.33 (P < 0.01) respectively. In addition, the reduction of TSI index correlated significantly with that of Ts-SD (r = 0.75, P < 0.05). CONCLUSIONS: CRT could immediately improve the systolic and diastolic synchrony of the left ventricle and ventricular function. TSI and TTI may be as the new effective modalities to assess the mechanical dyssynchrony. TSI index was direct and reliable in this study.

Aged↗
PubMed2005

[Expression of aurora-A kinase in human lung cancer cell lines PG, A549, and NCI-H460].

BACKGROUND & OBJECTIVE: Recent researches found that Aurora-A overexpresses in various malignancies. This study was to detect the expression of Aurora-A in lung cancer cell lines PG (highly-metastatic giant cell lung cancer), A549 (lung adenocarcinoma), and NCI-H460 (large cell lung cancer) and explore its correlation to DNA content, provide a theoretical basis for screening tumor marker and molecular therapeutic target of lung cancer. METHODS: mRNA and protein levels of Aurora-A in PG, A549, and NCI-H460 cells were detected by reverse transcription-polymerase chain reaction(RT-PCR) and Western blot. Flow cytometry was used to analyze DNA contents in cell cycles of PG, A549, and NCI-H460 cells. RESULTS: mRNA level of Aurora-A was 1.14 in PG cells, 1.16 in A549 cells, and 0.84 in NCI-H460 cells, respectively; protein level of Aurora-A was 8.96 in PG cells, 21.13 in A549 cells, and 6.43 in NCI-H460 cells, respectively. The proportion of cells with tetraploid DNA was 19.88% in PG cells, 14.97% in A549 cells, and 10.6% in NCI-H460 cells, respectively (P<0.01); the proportion of cells with polyploid DNA was 2.66% in PG cells, 3.59% in A549 cells, and 2.30% in NCI-H460 cells, respectively. CONCLUSION: Aurora-A is overexpressed in the 3 lung cancer cell lines, but the mRNA levels are different.

Adenocarcinoma↗
PubMed2005

[Treatment of erectile dysfunction after radical retropubic prostatectomy with PDE5 inhibitor].

The rate of erectile dysfunction after radical retropubic prostatectomy is from 10% to 100%. The prevalence of erectile dysfunction after nerve-sparing radical prostatectomy is more than one third. In the patients who had undergone bilateral NS, 72% responded to sildenafil, 71.7% and 59.7% responded to 20 mg and 10 mg of vardenafil respectively. For all randomized patients who received tadalafil, the mean percentage of successful penetration attempts was 54% and the mean percentage of successful intercourse attempts was 41%. For the subgroup with evidence of postoperative tumescence these values were 69% and 52%, respectively. No head-to-head trials have been performed with sildenafil, vardenafil and tadalafil in treatment of erectile dysfunction after radical prostatectomy.

Carbolines↗
PubMed2005

[Pharmacokinetic study of intraperitoneal chemotherapy with HCPT].

OBJECTIVE: To study the pharmacokinetic of 10-Hydroxycamptothecin HCPT by intraperitoneal administration. METHOD: Six dogs were given HCPT by intraperitoneal perfusion: HCPT 2 mg x kg(-1), dissolved in 300 mL NS. During the course of experiments, peritoneal fluids and blood were sampled using a standardized protocol. The concentration of HCPT in all samples was determined by high performance liquid chromatography (HPLC). RESULT: The area under the curve (AUC) of peritoneal fluids was significantly highly as compared to the AUC of femoral vein and portal vein (P < 0.001). CONCLUSION: These experiments demonstrate that intraperitoneal chemotherapy has significant effect on the pharmacokinetics of IP route of HCPT administration. This method should be a more reasonable chemotherapy for the prevention of recurrence and liver metastasis of gastric cancer, colon cancer and ovary cancer after radical resection.

Animals↗
PubMed2005

[Uvulopalatopharyngoplasty and tongue base coblation treat the 112 cases of severe obstructive sleep apnea -hypopnea syndrome].

OBJECTIVE: To study the effect of the combination of UPPP and tongue base Coblation in treatment of the severe OSAHS. METHOD: One hundred and twelve cases who were diagnosed as severe OSAHS by polysomnography (PSG) were treated surgically by UPPP and tongue base Coblation. RESULT: The follow up period was twelve months. Twenty-four cases were cured, 52 cases have notable effects, 16 cases had effects, 20 cases had no effects. The total ratio of validity was 82.1%. CONCLUSION: The combination of UPPP and tongue base Coblation is a effective method for severe multi-level OSAHS treatment.

Adult↗
PubMed2004

Enhancer-dependent splicing of FGFR1 alpha-exon is repressed by RNA interference-mediated down-regulation of SRp55.

The FGFR1 gene transcript is alternatively processed to produce functionally different receptor forms. Previously, we identified a 69-nucleotide exonic splicing enhancer (ESE) required for alpha-exon inclusion in JEG3 cells. In the present study, we found that this sequence is composed of three independent elements, two smaller ESE sequences flanking an exonic splicing silencer sequence. Ultraviolet cross-linking and immunoprecipitation identified ESE-specific binding of the splicing regulator SRp55. A RNA interference-mediated decrease in SRp55 confirmed the significance of this interaction. There was a 6- to 14-fold decrease in exon inclusion on ablation of SRp55. In SNB19 glioblastoma cells, which normally skip this exon, SRp55 was also demonstrated to play a role in exon inclusion after the removal of intronic splicing silencer sequences. These observations indicate that SRp55 plays a major role in maintaining normal FGFR1 alpha-exon inclusion, which is subject to dominant intronic splicing silencer-mediated and exonic splicing silencer-mediated inhibition in SNB19 cells.

Alternative Splicing↗
PubMed2004

Correction of aberrant FGFR1 alternative RNA splicing through targeting of intronic regulatory elements.

Alternative RNA splicing is now known to be pervasive throughout the genome and a target of human disease. We evaluated if targeting intronic splicing regulatory sequences with antisense oligonucleotides could be used to correct aberrant exon skipping. As a model, we targeted the intronic silencing sequence (ISS) elements flanking the alternatively spliced alpha-exon of the endogenous fibroblast growth factor receptor 1 (FGFR1) gene, which is aberrantly skipped in human glioblastoma. Antisense morpholino oligonucleotides targeting either upstream or downstream ISS elements increased alpha-exon inclusion from 10% up to 70% in vivo. The effect was dose dependent, sequence specific and reproducible in several human cell lines, but did not necessarily correlate with blocking of protein association in vitro. Simultaneous targeting of the ISS elements had no additive effect, suggesting that splicing regulation occurred through a shared mechanism. Broad applicability of this approach was demonstrated by similar targeting of the ISS elements of the human hnRNPA1 gene. The correction of FGFR1 gene splicing to >90% alpha-exon inclusion in glioblastoma cells had no discernable effect on cell growth in culture, but was associated with an increase in unstimulated caspase-3 and -7 activity. The ability to manipulate endogenously expressed mRNA variants allows exploration of their functional relevance under normal and diseased physiological states.

Alternative Splicing↗