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Wei Xie

Publications and source records attributed to Wei Xie.

53 records · Page 3Linked to original sources
PubMed2004

[Preparation and specificity analysis of anti-Drosophila Dxl6 antibody].

In order to study the function of Dxl6 which is a novel member of SR protein family, its cDNA was cloned by RT-PCR, and the sequences of its RS domain and its middle part were subcloned into two fusion express vectors, pGEX-4T-1His(6)C and pET32a. After expressing in E.coli BL21, the truncated proteins of Dxl6 RS domain part and Dxl6 middle part in pGEX-4T-1His(6)C were purified and used to immunize rabbits. Purified antibodies against the RS domain and Dxl6 middle part were obtained by affinity chromatography with the expressed products of Dxl6 RS domain part and Dxl6 middle part in pET32a, respectively. The result shows the antibody against Dxl6 RS domain has a good specificity to Dxl6 in Drosophila larvae by Western blot analysis.

Animals↗
PubMed2004

[Pathogens and drug resistance of nosocomial pneumonia after intracranial surgery].

OBJECTIVE: To determine the antimicrobial resistance and bacterial distribution of nosocomial pneumonia in neurosurgical patients. METHODS: We analyzed and counted the result of sputum culture, drug sensibilities test, and the rate of nosocomial pneumonia after intracranial surgery of all the patients in the Department of in Neurosurgery our hospital in 2002. RESULTS: The rate of nosocomial pneumonia after intracranial surgery was 6.2%. The first 5 strains were pseudomonas aeruginosa, acinetobacter, enterobacteriaceae, klebsiella, and staphylococcus epidermidis. Statistics of drug sensibility test suggested:the rate of ampicillin and cefuroxime resistance was over 83%. Gram-negative bacterium was the first sensitive to sulperazon and imipenem. Gram-positive bacterium was the first sensitive to vancomycin, ampicillin/sulbactam and rifampicin. CONCLUSION: The rate of neurosurgical infection was high. The most common pathogens were gram-negative bacteria. Drug resistance was serious.

Adolescent↗
PubMed2003

[The association of sulfotransferase1A1 His allele and breast cancer in Han ethnic Chinese women].

OBJECTIVE: To assess the relationship between SULT1A1 Arg213His polymorphism and breast cancer in Hans of Chinese women, as well as the interaction of the polymorphism and related risk factor of breast cancer. METHODS: Distribution of Arg213His polymorphism of the SULT1A1 gene was detected by using PCR-RFLP in 209 cases of breast cancer and 426 matched healthy controls. The OR of susceptibility of SULT1A1 genotypes to breast cancer and the r value of interaction with exposure factors using multivariate logistic regression. RESULTS: (1) There was no significant difference in genotype of Arg/Arg, Arg/His and His/His of SULT1A1 between case and control (P = 0.12). The frequency of His allele was 13.6% and 9.5% in were determined case and control, respectively, P = 0.03; (2) Compared with Arg/Arg genotype, the risk of Arg/His and His/His was increased, P for trend = 0.04; The OR of His allele (Arg/His + His/His) was 2.60 (95% CI: 1.12 - 6.05, P = 0.04); (3) As for the interaction between gene and related exposure factors, His allele strengthen the effect of endogenous estrogen exposure (interaction index r > 1), and weaken the effect of factors related to exposure of some procarcinogen in dietary (r < 1), both being multiplicative interaction model. CONCLUSION: SULT1A1 His allele is positively associated with the risk of breast cancer, and an interaction exist between this allele and related exposure factors.

Adult↗
PubMed2003

Chemical trapping and crystal structure of a catalytic tRNA guanine transglycosylase covalent intermediate.

Prokaryotic tRNA guanine transglycosylase (TGT) catalyzes replacement of guanine (G) by 7-aminomethyl-7-deazaguanine (PreQ1) at the wobble position of four specific tRNAs. Addition of 9-deazaguanine (9dzG) to a reaction mixture of Zymomonas mobilis TGT and an RNA substrate allowed us to trap, purify and crystallize a chemically competent covalent intermediate of the TGT-catalyzed reaction. The crystal structure of the TGT-RNA-9dzG ternary complex at a resolution of 2.9 A reveals, unexpectedly, that RNA is tethered to TGT through the side chain of Asp280. Thus, Asp280, instead of the previously proposed Asp102, acts as the nucleophile for the reaction. The RNA substrate adopts an unusual conformation, with four out of seven nucleotides in the loop region flipped out. Interactions between TGT and RNA revealed by the structure provide the molecular basis of the RNA substrate requirements by TGT. Furthermore, reaction of PreQ1 with the crystallized covalent intermediate provides insight into the necessary structural changes required for the TGT-catalyzed reaction to occur.

Amino Acid Sequence↗
PubMed2003

Molecular detection of disseminated tumor cells in the peripheral blood in patients with gastrointestinal cancer.

PURPOSE: In this study, 62 preoperative peripheral blood samples from patients with gastrointestinal carcinomas, 12 healthy volunteers, and ten patients with inflammatory gastrointestinal diseases were analyzed for the determination of CEA, CK19, and CK20 mRNA expression in peripheral blood, and its clinical significance was evaluated. METHODS: Nested reverse transcriptase-polymerase chain reaction (nested RT-PCR) was used to analyze CEA, CK19, and CK20 mRNA expression in peripheral blood. Fresh tumor tissues from patients with colorectal cancer (n=15) were used as a positive control. RESULTS: Among 62 blood samples from patients with gastrointestinal cancer, the expression of CEA, CK19, and CK20 mRNA was 51.6% (32/62), 35.5% (22/62), and 48.4% (30/62), respectively. 74.2% (46/62) were positive for at least one marker. Fifteen tumor tissues were all positive for CEA, CK19, and CK20 mRNA. Only one blood sample from patients with no gastrointestinal carcinoma was positive for CEA mRNA. CONCLUSION: Our results indicate that the molecular detection of circulating tumor cells in peripheral blood in patients with gastrointestinal carcinoma was significantly correlated with its malignant biological properties, and may be helpful in the selection of clinical treatment and judgment of prognosis.

Adult↗
PubMed2003

Immunotherapy of cytotoxic T cell-resistant tumors by T helper 2 cells: an eotaxin and STAT6-dependent process.

Currently most attempts at cancer immunotherapy involve the generation of CD8(+) cytotoxic T lymphocytes (CTLs) against tumor-associated antigens. Many tumors, however, have been immunoselected to evade recognition by CTLs and thus alternative approaches to cancer immunotherapy are urgently needed. Here we demonstrate that CD4(+) T cells that recognize a secreted tumor-specific antigen and exhibit a cytokine secretion profile characteristic of Th2 cells, are capable of clearing established lung and visceral metastases of a CTL-resistant melanoma. Clearance of lung metastases by the Th2 cells was found to be totally dependent on the eosinophil chemokine, eotaxin, and partially dependent on the transcription activator signal transducer and activator of transcription 6 (STAT6), with degranulating eosinophils within the tumors inducing tumor regression. In contrast, tumor-specific CD4(+) Th1 cells, that recruited macrophages into the tumors, had no effect on tumor growth. This work provides the basis for a new approach to adoptive T cell immunotherapy of cancer.

Animals↗
PubMed2003

Preparation and characterization of polyclonal antibodies against ARL-1 protein.

AIM: To prepare and characterize polyclonal antibodies against aldose reductase-like (ARL-1) protein. METHODS: ARL-1 gene was inserted into the E. coli expression vector pGEX-4T-1(His)(6)C and vector pQE-30. Recombinant ARL-1 proteins named ARL-(His)(6) and ARL-GST were expressed. They were purified by affinity chromatography. Sera from domestic rabbits immunized with ARL-(His) (6) were purified by CNBr-activated sepharose 4B coupled ARL-GST. Polyclonal antibodies were detected by Western blotting. RESULTS: Recombinant proteins of ARL-(His)(6) with molecular weight of 35.7 KD and ARL-GST with molecular weight of 60.8 KD were highly expressed. The expression levels of ARL-GST and ARL-(His)(6) were 15.1 % and 27.7 % among total bacteria proteins, respectively. They were soluble, predominantly in supernatant. After purification by non-denatured way, SDS-PAGE showed one band. In the course of polyclonal antibodies purification, only one elution peak could be seen. Western blotting showed positive signals in the two purified proteins and the bacteria transformed with pGEX-4T-1(His) (6) C-ARL and pQE-30-ARL individually. CONCLUSION: Polyclonal antibodies are purified and highly specific against ARL-1 protein. ARL-GST and ARL-(His) (6) are highly expressed and purified.

Aldehyde Reductase↗
PubMed2003

[The expression and imprinting status of insulin-like growth factor 2 gene in colorectal cancer].

OBJECTIVE: To study the imprinting status and expression level of insulin-like growth factor 2 (IGF2) gene in colorectal cancer and to provide a clue for the mechanism of carcinogenesis of colorectal cancer. METHODS: The expression levels of IGF2 in the paired colorectal cancer and adjacent normal tissue were examined and compared by use of semi-quantitative reverse transcription-polymerase chain reaction. The imprinting status of IGF2 was detected by restriction fragment length polymorphism. The relationships between the expression level of IGF2, its imprinting status, and the carcinogenesis of colorectal cancer were analyzed. RESULTS: IGF2 was overexpressed in 82.4% (28/34) of colorectal cancer tissues which was significantly higher than those of the matched normal tissues (P<0.01, t=3.01). 87.5% (14/16) of colorectal cancer showed loss of imprinting(LOI), while 71.4%(10/14) of normal tissues also displayed LOI of IGF2. CONCLUSION: Overexpression of IGF2 was found to play an important role in carcinogenesis of colorectal cancer. LOI of IGF2 may be a prophase manifestation of colorectal cancer.

Colorectal Neoplasms↗
PubMed2003

[Evaluation of glucocorticoid in treatment for patients with acute respiratory distress syndrome].

OBJECTIVE: To value of glucocorticoid (GC) in treatment for patients with acute respiratory distress syndrome (ARDS) was evaluated. METHODS: The clinical data from all patients with ARDS in medical ICU (MICU) during May 2000 to Aug. 2002 were collected. They were divided into two groups, GC and non-GC groups, in order to compare their age, sex, acute physiology and chronic health evaluation II (APACHE II) score, PaO2/FiO2, Qs/Qt, level of positive end-expiratory pressure(PEEP), mortality and dead reason of death, depending on whether GC was given or not. In cases with administration of GC, the dosage, as well as duration of treatment was analyzed in terms of the overcome. RESULTS: There were 77 cases totally, among them 60 cases were of GC group and 17 of non -GC. Their age, sex, APACHE II score, PaO2/FiO2, Qs/Qt, use of artificial ventilation and its duration, level of PEEP, and the extent of relief from hypoxemia showed no significant differences between two groups (P>0.05). Even the mortality for patients who were treated with GC was higher than those without (71.7% vs. 52.9%), though there was no statistically significant difference (P>0.05). The percentage of patients died primarily of ARDS was low in both groups (7.0% and 11.1%). The age, APACHE II score and underlying diseases for non-survivors were older and higher than survivors (P<0.001 or P<0.005) and their duration of staying in ICU was shorter than the latter (P<0.05). The mortality of patients who were given GC before or during 24 hours of the establishment of the diagnosis of ARDS (66.7% and 68.2%) was lower than those who were given GC 24 hours after the diagnosis of ARDS (90.0%). CONCLUSION: GC could be one of effective treatments for ARDS, and it should be given without hesitation when refractory hypoxemia and shock were found.

APACHE↗
PubMed2003

[Evaluation of glucocorticoid in treatment for patients with acute respiratory distress syndrome as a result of serious community-acquired pneumonia].

OBJECTIVE: To evaluate the usage of glucocorticoid (GC) in treatment for patients with acute respiratory distress syndrome (ARDS) resulting from serious community-acquired pneumonia (SCAP). METHODS: The clinical data from all patients with ARDS resulting from SCAP in medical ICU (MICU) from May 2000 to Feb. 2003 were collected. Their age, sex, acute physiology and chronic health evaluation (APACHE II) score, PaO(2)/FiO(2) and Qs/Qt, the severity of SCAP, mechanical ventilation (MV) and the level of positive end-expiratory pressure (PEEP), time of stay in ICU, improvement of SCAP and oxygenation, as well as mortality and reasons of death were analyzed, respectively. So was did the influence of administration of GC on hypoxemia, septic shock, and their prognosis. RESULTS: There were 24 cases totally, among them 7 patients had not taken GC, and 5 patients were cured (71.4 percent), and the other 2 cases died (28.6 percent) Their direct cause of death were multiple organ dysfunction syndrome (MODS) and ARDS, respectively In 17 cases GC was given because hypoxemia and septic shock could not be alleviated with ordinary therapy, including MV Among them only 5 patients (29.4 percent) were cured, and all others (12 cases, 70.6 percent) died, and the major direct cause of death was MODS (6 cases, 75.0 percent). A few of them died of ARDS and septic shock (1 case, 12.5 percent, respectively). The severity of SCAP, as well as other clinical data of the survivors, showed no significant difference compared with the nonsurvivors (P>0.05). But except for their PaO2/FiO2, Qs/Qt and shock, their pulmonary infection was better controlled than deaths (P<0.001). CONCLUSION: Refractory hypoxemia and septic shock of patients with pulmonary ARDS might be alleviated by GC when they are treated with routine methods, including MV, thus it enabled to win the time for other effective treatments.

APACHE↗
PubMed2003

[Study on the estrogenic effect of the organic extracts from tap water and source water].

In order to study the estrogenic effects of the organic extracts from tap water and source water, two in vitro assay and one in vivo short-term assay were performed to detect the estrogen-like activity of the component of water. The results showed that at the concentration of 50 ml relevant to real water, the recombinant yeast assay and MCF-7 cell proliferation assay could both detected the estrogen-like activity and with increase of concentration, the component exhibited an increasing estrogenic effects. The dose inducing the maximum effect in cell proliferation assay was 250 ml and in recombinant yeast assay was 1250 ml. Exceed this dose with increasing concentration, the estrogenic effects of component decreased both in two assay. In uterrtropic assay, doses of 10 L/kg and 50 L/kg increased the weight of uterus of 18 day ICR female mice significantly. All above findings indicated that organic extracts from source water exhibited the estrogenic effects. The series of 3 bioassay process displayed sensitivity and practicability.

Animals↗
PubMed2003

[Study on the pharmacokinetics and bioavailability of syringic acid in rabbits].

OBJECTIVE: To study the pharmacokinetics and bioavailability of syringic acid(SA) in rabbits by HPLC. METHOD: After the rabbits were injected SA injection via ear vein and peritoneal cavity, blood was collected also via ear vein at different time-point. Then the concentration of SA in blood was determined by HPLC and the concentration-time curve was mapped to simulate a compartment model. So the pharmacokinetic parameters were calculated out. Several days after this injection, the drug was administered to the rabbits via i.p. and using the same method, another concentration-time curve was obtained. By comparing the AUC of the two curves, bioavailability was obtained. RESULTS: The concentration-time curve of SA in rabbits after i.v. fitted in a two-compartment open model and the absolute bioavailability was 86.27%. CONCLUSION: The results were valuable for the clinical application of new anti-endotoxic drug from Radix Isatidis.

Animals↗
PubMed2003

[Construction and screening of hepatitis E virus-specific phage antibody combinatorial library].

AIM: To construct HEV-specific phage combinatorial anti-body library and screen anti-HEV antibodies with neutralizing activity from the library. METHODS: The total RNA was extracted from B-lymphocytes of 6 HE patients. Kappa chain and Fd segment of IgG gene were amplified respectively by RT-PCR using a set of Fab-specific primers. The amplified gene were inserted successively into vector pComb3 and electrotransformed E. coli XLI-Blue cells. Furthermore, the recombinant phage was rescued by being concultured with helper phage VCSM13 to construct HEV-specific phage anti-body library. RESULTS: Fab displayed on the surface a as fusion protein with the N terminal of coat protein III, and 1. 8 x 10(7) clone library was established. Specific antibodies to HEV ORF2 recombinant antigen were acquired after five rounds of panning with HEV ORF2 recombinant antigen including neutralizing epitope. CONCLUSION: Four clones exhibited specific binding to HEV ORF2 recombinant antigen including neutralizing epitope is identified by ELISA. The results show that we have got the recombinant phage antibodies.

Hepatitis Antibodies↗
PubMed2003

[Preparation of antibodies against a novel leucine-zipper protein, Ecp].

The aim of this research is to prepare high quality polyclonal antibodies against Ecp, a recently identified leucine-zipper protein. The full length cDNA of ecp was amplified by PCR, cloned into pGEX-4T-1(His)6 and transformed into E. coli DH 5alpha. After induction with IPTG, the GST-Ecp fusion protein from the lysate was bound to glutathione-Sepharose 4B and digested with thrombin. The released Ecp protein was further purified through Ni-NTA affinity chromatography to homogeneity. A rabbit was immunized with the purified Ecp, and the antibody generated against Ecp was purified by affinity chromatography. The results of the Western blot showed that Ecp is present in various development stages of Drosophila melanogaster, from larvae to adult.

Animals↗
PubMed2002

Regulation of Gli1 transcriptional activity in the nucleus by Dyrk1.

To investigate the cellular role of dual specificity Yak1-related kinase (Dyrk) 1, a nuclear localized dual specificity protein kinase, we examined its effect on transcriptional regulation using reporter gene assays. We found that Dyrk1 can substantially enhance Gli1-dependent, but not LEF-1-, c-Jun-, or Elk-dependent, gene transcription. In part, Dyrk1 does this through retaining Gli1 in the nucleus. However, we also demonstrate that Dyrk1 can enhance the transcriptional activity of Gli1-AHA, a nuclear export mutant, suggesting that Dyrk1 may be more directly involved in regulating the transcriptional activity of Gli1. In addition, Dyrk1 acted synergistically with Sonic hedgehog (Shh) to induce gene transcription and differentiation in mouse C3H10T1/2 cells. The failure of Shh to stimulate Dyrk1 kinase activity suggests that Dyrk1 may not be directly regulated by the Shh signaling pathway but functionally interacts with it. Thus, Gli1 transcriptional activity may be subjected to further regulation in the cell nucleus by a pathway distinct from Shh signaling, one mediated by Dyrk1.

3T3 Cells↗
PubMed2002

gp130-linked signal transduction promotes the differentiation and maturation of dendritic cells.

In order to explore the role of gp130-linked signal transduction in the differentiation and maturation of dendritic cells (DC), the mAb, B-S12, an agonist of gp130, was used for the activation of gp130 on DC. The effects of cytokines and of anti-gp130 mAb on the proliferation of DC, and their expression of IL-12 and CD80 (B7-1) by DC were evaluated. DC differentiating from peripheral blood mononuclear cells did not express the IL-6 receptor alpha chain, but expressed gp130. Anti-gp130 mAb promoted the proliferation of DC, induced by IL-4 and granulocyte macrophage colony stimulating factor (GM-CSF), by up-regulating the GM-CSF receptor on DC. DC induced by gp130 mAb and cytokines expressed DC-derived CC chemokine, as measured by RT-PCR. Induced DC also stimulated strong proliferation of autologous T cells in mixed lymphocyte reaction since an up-regulated expression of IL-12 and CD80 (B7-1) was observed in DC activated by anti-gp130 mAb. Thus, gp130 signal transduction is important for the differentiation and maturation of DC.

Adult↗