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Wei Song

Publications and source records attributed to Wei Song.

At least 55 records · Page 3Linked to original sources
PubMed2004

Urantide mimics urotensin-II induced calcium release in cells expressing recombinant UT receptors.

Urotensin-II is the natural ligand of the UT receptor. This novel system is involved in the regulation of cardiovascular functions. Recently, a urotensin-II analog ([Pen5,DTrp7,Orn8]urotensin-II(4-11)) named urantide, has been proposed as a selective and potent UT receptor antagonist. In order to pharmacologically characterize this new compound, urantide was tested on the native UT receptors of the rat aorta and on the human recombinant receptors expressed in CHO cells (CHO(hUT)). Indeed, urantide behaves as a competitive, potent (pA2 8.24), and pure antagonist in the rat aorta bioassay, while as an agonist (pEC50 8.11) in a calcium mobilization assay performed in CHO(hUT) cells. Urantide should be considered a low efficacy partial agonist.

Animals↗
PubMed2004

Cytokine and chemokine gene polymorphisms among ethnically diverse North Americans with HIV-1 infection.

Twenty-four common single nucleotide polymorphisms (SNPs) in 10 cytokine and chemokine genes were defined in 579 North Americans at high risk of HIV-1 infection due to sexual behavior and injection drug use. Among the 3 major ethnic (African-American, Hispanic/Latino, and other) groups involved, HIV-1-seropositive individuals differed significantly from ethnically matched HIV-1-seronegative individuals (odds ratios = 2.13-4.82; P = 0.003-0.05) for several SNPs and haplotypes defined at the IL4, IL4R, IL6, IL10, CCL5 (RANTES), and CXCL12 (SDF1) loci. In addition, the homozygous IL4-590T/T genotype was associated with higher (+87-131 cells/microL) CD4 T-cell counts in HIV-1-infected and AIDS-free adolescents not receiving antiretroviral therapy (adjusted P = 0.004). No SNPs at IFNG, IL2, IL12B, TNF, or CCL2 (MCP1) showed any association with HIV-related outcomes. Additional typing for IL1A, IL1B, IL1R1, IL1RN, and TGFB1 SNPs also failed to demonstrate any influence on HIV-1 infection or virologic/immunologic control in more selected patient groups. Coupled with previous findings, our data suggest that heritable IL4 and IL10 variations may contribute to the acquisition or progression of HIV infection and that the effects of other targeted loci in the cytokine and chemokine system cannot be established unequivocally in the study populations.

Adolescent↗
PubMed2004

Catalytic, asymmetric synthesis and diastereoselective aldol reactions of dipropionate equivalents.

The dimer of methylketene can be conveniently prepared in one step and high enantiomeric excess from propionyl chloride, using a catalytic amount of a silylated cinchona alkaloid as a source of chirality. Opening of the dimer with a lithiated sulfonamide affords a beta-ketosulfonimide, which undergoes Sn(II)-mediated aldol reactions to diastereoselectively afford the anti,syn-aldol adduct. Alternatively, reduction of the dimer to the beta-hydroxy ketone, followed by acylation, affords a beta-acyloxyl ketone that undergoes diastereoselective, dialkylboron chloride-mediated aldol reactions to produce the anti,anti-aldol adduct.

Aldehydes↗
PubMed2004

HLA and cytokine gene polymorphisms are independently associated with responses to hepatitis B vaccination.

Variable immune responses to hepatitis B virus (HBV) infection and recombinant HBV vaccines have been associated with polymorphisms in several genes within the human leukocyte antigen (HLA) complex. Analyses of polymerase chain reaction (PCR)-based genotyping data from 164 North American adolescents vaccinated with recombinant HBV products confirmed that HLA-DRB1*07 (relative odds [RO] = 5.18, P <.0001) and human immunodeficiency virus type 1 (HIV-1) infection (RO = 3.91, P <.001) were both associated with nonresponse to full-dose vaccination. Further associations were observed with single nucleotide polymorphisms (SNPs) at the IL2 and IL4 loci along with insertion/deletion variants at the IL12B locus (P =.003-.01). Host genetic associations were independent of one another as well as other HLA (A, B, C, and DQB1) and cytokine gene (IL4R, IL6, IL10, and TNF) variants. Statistical adjustments for nongenetic factors (gender, ethnicity, age, HIV-1 infection, and vaccination protocols) did not substantially alter the strengths of the genetic relationships. The overall distribution pattern of genetic variations was similar between the analyzed vaccinees and additional adolescents (n = 292) from the same cohort. In conclusion, DRB1*07 (or a closely linked allele) and immunoregulatory cytokine gene polymorphisms correlate with variable immune response to recombinant HBV vaccines.

Cohort Studies↗
PubMed2004

Persistence of mutations during replication of an HIV library containing combinations of selected protease mutations.

It has been known that, in some cases, accumulation of specific mutations in HIV-1 protease leads to multi-protease inhibitor (PI) resistance. We examined the persistence of mutations detected in HIV-1 clinical isolates cross-resistant to the current PIs using an HIV-1 protease restricted library (HXB2 protease in an HIV-1(NL4-3) background) in the absence of protease inhibitors. The virus library contained combinations of 0-11 amino acid substitutions (4,096 possible combinations) in the protease-encoding region. We examined the frequency of each amino acid substitution in the library using a T cell line, MT-2. The frequency of the amino acid substitutions V82T/I and L90M decreased rapidly with a short half life (t(1/2) < 10 days). However, the mutations M36I, M46I and I84V were relatively persistent: t(1/2) = 34.2, 28.1 and 30.6 days, respectively. Other amino acid substitutions, i.e., L10I, I54V, L63P, A71V and V82A, were well retained (t(1/2) > 36 days). By contrast, the half lives (t(1/2)) of the D30N and N88D mutations associated with nelfinavir (NFV) resistance were only 7.2 and 1.8 days, respectively. These results indicate that this type of the HIV-1 protease restricted library is useful to evaluate the persistence of PI resistance-associated mutations in the absence of drug selective pressure.

Amino Acid Sequence↗
PubMed2004

Aortic eNOS expression and phosphorylation in Apo-E knockout mice: differing effects of rapamycin and simvastatin.

BACKGROUND: The inhibition of nitric oxide (NO) by hypercholesterolemia may be mediated, in part, by interactions with caveolin-1 (Cav-1). Because of the facilitatory effects of statins on endothelial function and the adverse effects of rapamycin (RAPA) on plasma lipids, we compared the effects of simvastatin (SMV) and RAPA on endothelial NO synthase (eNOS) and Cav-1 protein expression and phosphorylation in the aortas of apolipoprotein E (Apo-E) knockout (-/-) mice. METHODS: Apo-E -/- mice (n = 38) fed a high-cholesterol diet were given SMV (100 mg/kg/day po), RAPA (3 mg/kg/day ip), or no treatment for 10 weeks. Blood was drawn for serum lipid analysis, and protein was extracted for Western immunoblotting. Selected aortic specimens from 2 animals in each group were examined by histology and immunohistochemistry. The data are expressed as the mean +/- SEM and compared by the Student t test and ANOVA. Significance was established as P < .05. RESULTS: Lipid levels at 10 weeks were similar in the 3 groups except for higher triglyceride levels in RAPA-treated animals. eNOS expression was highest in RAPA-treated mice, but the p-eNOS to eNOS protein expression ratio was significantly greater in the SMV treatment group compared to both RAPA and controls (P < .05). Both Cav-1 and p-Cav-1 expression was significantly lower in the SMV-treated animals (P < .05) compared to mice treated with RAPA. CONCLUSIONS: Although eNOS expression was greatest in the RAPA-treated mice, the expression of p-eNOS was similar in the RAPA- and SMV-treated animals. The increase in eNOS induced by RAPA and the inverse relationship between p-eNOS and Cav-1 protein expression observed with SMV treatment suggest different mechanisms for the regulation of aortic eNOS expression in Apo-E mice by these 2 agents.

Animals↗
PubMed2004

[Specification and application of cephalometric analysis and image database].

PURPOSE: To summarize the basic requirement of cephalometric analysis and database product concluded from practice, and apply related products to improve the levels of medical treatment, teaching and scientific research. METHODS: By the use of digital X ray machine, digital camera, oral endoscope,scanner to import the image into system database, to edit, measure, make diagram, analyze and store the images, to catalog diagnosis according to the different need of patient to make convenient for retrieving by group, to design multi-page electronic case report including oral general diagram, the result of diagnosis cataloging, the result diagram of analysis, picture and text report, all of the above mentioned constitute a complete patient database system. RESULTS: About 400 medical case were accumulated, and these improved evidently the effect to present the production of medical treatment to potential patients, were convenient to the professional communication between doctors and conformation of treatment plan, provided a solid foundation to multimedia teaching, and promoted the development of the task of graduate student and the task of scientific research. CONCLUSION: Using related product with perfect functions to develop standardized cephalometric analysis and build standardized patient's database including image information, when such information is accumulated to certain extent, will become the invaluable treasure of relevant medical institution, will bring the obvious effect to improve the level of medical treatment, teaching and scientific research.

Cephalometry↗
PubMed2004

[Purification and cloning of an antifungal protein from the rice diseases controlling bacterial strain Paenibacillus polymyxa WY110].

Paenibacillus polymyxa WY110, a plant growth-promoting bacteria strain isolated from rice rhizosphere could suppress the growth of various plant pathogens effectively. With (NH4)2SO4 fractional precipitation, DEAE-Sephadex A-50 chromatography and Sephacryl S-200 chromatography followed by tracks of fraction antagonistic assay and SDS-PAGE, an antifungal protein P2 with in vitro anti-Pyricularia oxyzae activity was isolated and purified. It was showed with antagonistic activity on PDA plates that the growth of Pyricularia oryzae was inhibited by 1.5 microg of P2 protein effectively. N-terminal amino acid residues analysis showed 24 amino acid sequence: H2N-Ala-Asn-Val-Phe-Trp-Glu-Pro-Leu-Ser-Tyr-Tyr-Asn-Pro-Ser-Thr-Trp-Gln-Lys-Ala-Asp-Gly-Tyr-Ser-Asn-. Using this amino acid sequence as a target, the similarity of P2 protein was searched with BlastP program on Internet. It was showed a high homology between the P2 protein and the precursors of beta-1, 3-1, 4-glucanases from Bacillus. The beta-1, 3-1, 4-glucanase activity of P2 protein was identified with the specific substrate lichenan. According to the N-terminal partial sequence of P2 protein and the C-terminal conserved sequence of beta-1, 3-1, 4-glucanase, the primers for both terminals were synthesized. Using the genomic DNA of WY110 as the template, the full-length sequence of the gene encoding P2 was amplified by high fidelity PCR, then cloned into pMD18-T vecter. Sequence analysis showed the 72 nucleotide sequence on 5'-end matched with the known 24 amino acid sequence on N-terminal of P2 protein. The sequence (GenBank Accession Number: AF284449) was 636 bp in length encoding 212 amino acids. Comparing with a beta-1, 3-1, 4-glucanase gene (gluB) from Paenibacillus polymyxa, the sequence homology for nucleotides and deduced amino acids were 84% and 88.7% respectively. The cloning of the gene encoding P2 protein would be a new potential objective gene for plant gene engineering.

Amino Acid Sequence↗
PubMed2004

[Preparation of alpha-toxin's protective antigen of clostridium perfringens type A and research for its primary immunological protective function].

Induced by 42 degrees C, the recombinant engineering bacterial pBV/cpa408 was highly expressed. After having been pelleted by 80% (NH4)2 SO4 and dialysised, the expressed protein was isolated and purified by the gel filtration choromatography. Then according to an amount of 1.0 mg/kg, the Kunming Mice (body weighted 18g) were immuned with the purified protein by intraperitoneal inoculation. One week after the first enhanced immunization, the Kunming Mice were attacked with an amount of 1.0MLD alpha-toxin, in which the eight mice immuned all survive and the control group all died. During the period of immunization, the titre of the mouse's serum antibody was measured by ELISA. One week after the first immunization, the titre of the mice's serum antibody was 1:800, but that of one week after the first enhanced immunization reached to 1:6400.

Animals↗
PubMed2003

Catalytic, asymmetric preparation of ketene dimers from acid chlorides.

[reaction: see text] The cinchona alkaloid-catalyzed dimerization of monosubstituted ketenes generated in situ from the reaction of acid chlorides and diisopropylethylamine yields ketene dimers in high yields and enantioselectivities. This reaction tolerates sterically demanding and functionally diverse substituents. Kinetic studies suggest that the rate-determining step for the reaction is the deprotonation of the acid chloride by the tertiary amine to form ketene and that the stereochemistry-forming step is addition of an ammonium enolate with ketene.

Acids↗
PubMed2003

Endophilin and synaptojanin hook up to promote synaptic vesicle endocytosis.

Clathrin-mediated endocytosis of synaptic vesicles requires molecular rearrangements of proteins as well as lipids. In this issue of Neuron, Schuske et al. and Verstreken et al. show that the lipid-modifying enzyme endophilin recruits and stabilizes the polyphosphoinositide phosphatase synaptojanin at nerve terminals. This remarkable pairing of two enzymatic activities promotes multiple steps of clathrin-mediated endocytosis of synaptic vesicles.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Immunomodulation of hepatic ischemic injury via increased Bcl-X(L) and decreased Bcl-X(S).

BACKGROUND: Although classic ischemia-reperfusion injury is mediated by reactive oxygen intermediaries, increasing evidence implicates a role for immune-mediated apoptosis during ischemic injury in transplantation. Herein, we report the effects of polyclonal rabbit anti-thymocyte globulin (rATG) on mediators of hepatic apoptosis during cold storage. METHODS: Three-month-old male Lewis rats were placed under halothane anesthesia and the portal vein cannulated. University of Wisconsin (UW) solution (35 ml) with (n = 5) and without (n = 5) 20 mg/kg anti-rat rATG was infused before hepatectomy. The liver was stored in UW solution +/- rATG (143 ng/ml) at 4 degrees C for various times up to 24 h. Specimens were terminal deoxyuridine nick end labeling-stained for apoptosis. Tissue lysates were analyzed by Western blotting and densitometry. RESULTS: Compared to UW alone, significantly fewer apoptotic cells were present in UW + rATG perfused and stored livers. There were early and sustained significant increases in Bcl-X(L) and decreases in Bcl-X(S) with rATG. There was an initial, but not sustained, significant decrease in Bax with rATG. Moreover, there was a significant one-third decrease in caspase-9 production with rATG at 0, 6, 12, and 18 h. CONCLUSION: Decreased proapoptotic Bcl-X(S) and increased antiapoptotic Bcl-X(L), as well as decreased downstream proapoptotic caspase-9 expression, during liver ischemia after treatment with rATG, all favor cell survival. Because apoptotic ischemic injury results in allograft dysfunction, preservation strategies that ameliorate such immunological effects may improve organ function.

Adenosine↗
PubMed2003

[Plain radiograph and CT features of 112 patients with SARS in acute stage].

OBJECTIVE: To retrospectively analyze the X-ray and CT features of patients with suggestive of SARS at the early stages. METHODS: The study comprised 112 patients (43 men, 69 women; aged from 16 to 82 year) with clinically proved SARS. Chest radiograph was performed in all the patients and CT of thorax in 22 patients during the first week of the onset. RESULTS: In the early stage, the most common findings were patchy ground-glass opacification (GGO) (79.5% on X-ray and 81. 8% on CT) and mixed lesions of GGO with irregular consolidation (21.4% on X-ray and 45.5% on CT) and/or granulomas (14.3% on X-ray and 27.3% on CT). A majority of lesions were located in the middle and lower field (70.9%) with peripheral distribution (69%). Other findings on CT included intralobular and interlobular septal thickening (carzy-paving pattern) (36.4%), bronchiectasis (18.2%) and small pleural effusion (22.7%). CONCLUSION: Common radiologic findings of SARS are ground-glass opacification and mixed lesions of GGO with irregular consolidation and/or granulomas and lower location and peripheral distribution.

Adolescent↗
PubMed2003

The N-terminal non-RGS domain of human regulator of G-protein signalling 1 contributes to its ability to inhibit pheromone receptor signalling in yeast.

Regulators of G-protein signalling (RGS) are a family of proteins that interact with G-proteins to regulate negatively G-protein coupled receptor (GPCR) signalling. In addition to a conserved core domain that is necessary and sufficient for their GTPase activating protein (GAP) like activity, RGSs possess N- and C-terminal motifs that confer distinct functional differences. In order to identify the role of the non-RGS region of human RGS1, we have characterized a series of fusions between RGS1 and GFP in a yeast mutant lacking the RGS containing SST2 gene. Using both halo assays as well as a GPCR responsive FUS1-LacZ reporter gene, we demonstrate that a RGS1-GFP fusion inhibits GPCR signalling in yeast while GFP fusions containing either the N-terminus non RGS sequence of RGS1(1-68) or the sequence containing the RGS box of RGS1(68-197) produce proteins that retain RGS1 activity. These results suggest that both the N-terminal and the RGS box of RGS1 function to inhibit signalling. Analysis of a series of mutants spanning the entire N-terminal non-RGS region of RGS1 produced by conservative segment exchange (CSE) mutagenesis showed little loss of function in yeast. This suggests that the overall structure of the N-terminal region of RGS1 rather than specific motifs or residues is required for its function.

Amino Acid Sequence↗
PubMed2003

[Cloning, expression of the lectin-EGF domain of P-selectin, and preparation of its monoclonal antibody].

To prepare monoclonal antibody specific to P-selectin lectin-EGF domain, the gene for lectin-EGF domain of P-selectin L-EGF was amplified from normal human platelets by RT-PCR, then was cloned into prokaryotic vector pET42b(+). The recombinant plasmid was transformed into E. coli DH5 alpha strain for further screening and characterization, and was expressed in E. coli BL21 strain. Expressed protein was purified by chromatography on a Ni(2+)-NTA superflow agarose column and eluted with pH 8.0-4.5 urea gradient. Then the mAb anti-lectin-EGF was prepared with classical hybridoma technique, and 3 hybridoma cell lines (B10, F3 and H5) were obtained with Ig subclasses of these mAbs were IgG(2), IgG(1), and IgG(3) respectively, and their light chains were all kappa chain. Immuofluorescence and FACS assays demonstrated that mAbs could specifically recognize P-selectin expressed on ECV (endothelial cell line) stimulated by LPS. Meanwhile, the role of mAbs to P-selectin lectin-EGF domain was studied, and it was proved that the mAbs markedly inhibited adhesion between platelets and neutrophils in vitro. These monoclonal antibodies can specifically recognize the natural P-selectin and markedly inhibit adhesion between platelets and neutrophils in vitro.

Animals↗
PubMed2003

[Implication of cochlear implantation in patients with enlarged vestibular aqueduct syndrome].

OBJECTIVE: To evaluate the intraoperative obstacles and post-operative outcomes of cochlear implantation in children with enlarged vestibular aqueduct syndrome. METHODS: Between May 1995 and June 2002, 10 patients with enlarged vestibular aqueduct syndrome received cochlear implantation in Pekin Union Medical College Hospital. The clinical records of 10 cases of enlarged vestibular aqueduct syndrome were analyzed retrospectively. RESULTS: Via cochleostomy pulsatile clear fluid gusher occurred in 8 cases, which were easily controlled by quickly inserting the electrode array and sealing the cochleostomy with muscle tissue in each instance. The implant was inserted without difficulty in all patients. There have been no post-operatively complications, and audiologic outcome of the 10 patients with cochlear implantation were almost the same as the other patients without inner ear malformations. Five cases of them can even speak better than the other prelingual deafness that may be attributed in part to postlingual deafness. CONCLUSIONS: Despite pulsatile clear fluid gusher in cochlear implantation, no post-operatively complications have been found, and the outcome of these 10 patients with cochlear implantation was excellent. Cochlear implantation can be safely and effectively performed in patients with profound sensorineural hearing loss (SNHL) associated with enlarged vestibular aqueduct syndrome.

Adolescent↗
PubMed2003

[Correlation of E-cadherin, beta-catenin and gamma-catenin gene expression with the invasion and metastasis of gastric carcinoma].

OBJECTIVE: To study the association of the expressions of E-cadherin, beta;- and gamma-catenins in gastric carcinoma tissues with the invasion and metastasis of the tumor. METHODS: From 60 patients with gastric carcinoma, the paraffin-embedded specimens including 60 carcinoma tissues, 20 precancerous lesions (10 intestinal metaplasia and 10 dysplasia specimens) and 20 corresponding normal tissues adjacent to the carcinomas were obtained for detecting E-cadherin, beta;- and gamma-catenin expressions by immunohistochemistry. RESULTS: Positive staining for E-cadherin, beta- and gamma-catenins was clearly observed on the cellular membrane throughout the epithelium in all the normal and metaplastic gastric mucosa. In 1 out of the 10 specimens of dysplastic mucosa, the staining for E-cadherin and beta;-catenin was absent but gamma-catenin staining appeared normal. Up to 80% (48/60) of the gastric carcinoma specimens presented abnormal staining for at least one of the components of the cadherin- catenin complex, showing a close correlation to Ming's classification, TNM staging and lymph node metastasis (P<0.05). The rates of abnormal expression were 6.67% for E-cadherin, 55% for beta;-catenin and 58.33% for gamma-catenin. CONCLUSIONS: Abnormal expression of E-cadherin, beta;- and gamma-catenins results in loss of epithelial cell-to-cell adhesion, with leads to uncontrolled cell growth, and may therefore participate in malignant transformation of the cells, and closely associates with the invasive growth and metastasis of human gastric carcinoma.

Cadherins↗