Biomedical subjects

Xue-Feng Wang

Publications and source records attributed to Xue-Feng Wang.

31 records · Page 2Linked to original sources

PubMed2004

[Effects of salidroside on carbohydrate metabolism and differentiation of 3T3-L1 adipocytes].

OBJECTIVE: To observe the effects of salidroside on carbohydrate metabolism and differentiation of 3T3-L1 adipocytes. METHODS: 3H-glucose uptaking rate in adipocytes treated by salidroside was detected. Adipocytes treated by salidroside in differentiation were stained by oil red O and analyzed by spectrophotography quantitatively. The expression of PPAR-gamma and C/EBP-alpha mRNA relating to differentiation of adipocytes was detected by reverse transcription PCR. RESULTS: 3H-glucose uptaking rate in the salidroside group was 110.4%, higher than that in the blank control group (P < 0.01). Salidroside suppressed the differentiation of 3T3-L1 pre-adipocytes and down-regulated the expression of PPAR-gamma and C/EBP-alpha mRNA (P < 0.01, vs control group). CONCLUSION: Salidroside promotes the 3H-glucose uptaking, suppresses the differentiation and down-regulates the expression of PPAR-gamma and C/EBP-alpha mRNA in 3T3-L1 adipocytes.

3T3-L1 Cells↗

PubMed2004

[In vivo transfection and expression of human coagulant factor VIII cDNA in mice].

The aim is to observe the expression of human factor VIII gene in mice tranduced in vivo and ex vivo. The vector pLNC-FVIII BD was generated by cloning a B-domain-deleted (760aa-1639aa) FVIII cDNA (FVIIIBD cDNA) into retroviral vector pLNCX. 2 x 10(6) of mouse bone marrow stroma cells transduced by LNC-FVIII BD were infused into 4-week-old BALB/c mice by tail-vein injection. pLNC-FVIII BD was conjugated with PAMAM dendrimer to form complex PAMAM-pLNC-FVIII BD, with which C57BL/6J were injected by tail vein (200 micro l contained 15 micro g/mouse) and sacrificed at days 1, 2, 7, 14, 21 and 28, respectively after injection. Tissue such as liver, spleen, lung and kindney were harvested, with which the transcription were detected by means of RT-PCR. In addition, blood was collected to be measured human FVIII Ag, human FVIIIc and anti-FVIII of human inhibitors. The results showed that the highest level of human FVIII in the recipient BALB/c mice was 8.6 +/- 1.44 ng/ml detected on the first day post-injection; anti-FVIII antibodies were detected from the first week post-injection, and then the level of FVIII Ag decreased and cannot be measured on the fourth week. In the C57BL/6J mice physiological level of human FVIII was expressed in plasma at 48 hours after injection and the average human FVIIIc was 0.62 U/ml and the average human FVIII Ag was 115.5 ng/ml, and gradually reduced later. Anti-FVIII of human inhibitors was not revealed all the time. Syngene image scanning demonstrated that the transcription of the human FVIII BD cDNA occurred mainly in spleen and lung, and secondarily in liver and kidney. No side effects of PAMAM-pLNC-FVIII BD were observed in mice tissue by pathological examination at 4 weeks. In conclusion, retrovirus-transduced bone marrow stroma cells effectively produced human FVIII after ex vivo transduction, but the development of anti-FVIII antibodies in recipient mice influenced the expression level. The human FVIII gene can successfully be transduced in vivo through injecting PAMAM-pLNC-FVIII BD cDNA into mice intravenously. There was physiological level expression of human FVIII in plasma at 48 hours after injection and the average human FVIIIc is 0.62 U/ml and the peak in the six mice was 0.89 U/ml, and gradually reduced later.

Animals↗

PubMed2004

[FXI gene mutations in two pedigrees of congenital clotting factor XI deficiency].

OBJECTIVES: To identify the FXI gene mutations in two Chinese pedigrees of congenital factor XI deficiency. METHODS: The peripheral blood samples were collected from the probands and their family members and the plasma FXI:C and FXI:Ag were determined. All the exons and exon-intron boundries of FXI gene were amplified with PCR and sequenced thereafter. RESULTS: A nonsense mutation Trp228stop and two missense mutations Glu323Lys and Leu172Pro were disclosed in the two pedigrees. All mutations existed in a heterozygous state. CONCLUSION: The FXI gene mutations Trp228stop, Glu323Lys and Leu172Pro attribute to the pathogenesis of the congenital factor XI deficiency in Chinese. The Leu172Pro is identified for the first time.

Adult↗

PubMed2004

[Double heterozygous mutations of non-canonical splice (IVS1a + 5g > a) and His348Gln caused inherited coagulation factor VII deficiency].

OBJECTIVE: To investigate the pathogenesis of inherited coagulation factor VII (FVII) deficiency. METHODS: The diagnosis was validated by coagulant parameter assay. FVII gene mutations were analysed in the proband by DNA direct sequencing of PCR products of all exons, exon-intron boundaries and the 3', 5'untranslated sequences. The mutations were confirmed by reverse sequencing. The ectopic transcripts of RT-PCR were used to confirm the characteristics of the mutation in non-canonical splice site (IVS1a + 5g > a). RESULTS: Double heterozygous mutations in the propositus were identified: a T to G mutation at position 10961, resulting in His348Gln substitution, a non-canonical splice site (IVS1a + 5g > a) mutation, causing the new model of splice and frameshift mutation. CONCLUSION: Double heterozygous mutations of His348Gln and IVS1a + 5g > a were identified in a propositus, the splicing pattern of the IVS1a + 5g > a mutation was reported for the first time.

Amino Acid Sequence↗

PubMed2004

Antiepileptic drug-induced multidrug resistance P-glycoprotein overexpression in astrocytes cultured from rat brains.

BACKGROUND: Intractable epilepsy may be due to multidrug resistance induced by conventional antiepileptic drugs. The phenomenon is sometimes associated with an overexpression of multidrug resistance gene 1 (MDR1). The purpose of this study was to determine if the overexpression of MDR1 could be induced in astrocytes from rat brains in vitro using antiepileptic drugs. METHODS: Astrocyte cell cultures from postnatal Wistar rats (within 24 hours of birth) were established. Different concentrations of the antiepileptic drugs phenytoin, phenobarbital, carbamazepine, and valproic acid were added to the cultures for 10, 20, or 30 days. The expression of P-glycoprotein (Pgp), the protein product of MDR1, was investigated with immunocytochemistry. RESULTS: Less than 5% of normal, untreated astrocytes had detectable Pgp staining at any time point. Phenytoin, phenobarbital, carbamazepine, and valproic acid induced the overexpression of Pgp in astrocytes in a dose- and time-dependent manner. Significantly higher levels of Pgp staining were detected at therapeutic concentrations of certain antiepileptic drugs (20 microg/ml phenobarbital, 40 microg/ml phenobarbital, and 20 microg/ml phenytoin) on day 30. Upregulation of Pgp was detected when using higher concentrations of phenytoin, phenobarbital, and valproic acid on day 20 and when using higher concentrations of any of the four antiepileptic drugs on day 30. CONCLUSIONS: Treatment with antiepileptic drugs may contribute to the overexpression in astrocytes of MDR1 and its protein product, Pgp. The mechanism leading to MDR must be considered in patients undergoing long-term treatment with antiepileptic drugs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2004

[Non-viral vector mediating human coagulation factor VIII gene expression in mouse 32D cell line].

To investigate the non-viral vector mediating human coagulation factor VIII gene expression in mouse 32D cell line, a recombinant plasmid vector, pRC/RSV-hFVIIIBDcDNA, was constructed by cloning B-domain-deleted (Delta760aa-1639aa) human factor VIII cDNA (hFVIIIBDcDNA) into plasmid vector, pRC/RSV. The plasmid RC/RSV-hFVIIIBDcDNA was then transfected by means of SuperFect Transfection Reagent into mouse 32D cell line. After screening with G418, the procoagulant activity (hFVIII:C) and antigen (hFVIII:Ag) of human factor VIII in the culture medium were detected using one-stage method and ELISA, respectively. Furthermore, RT-PCR was performed to observe the transcription of hFVIIIBDcDNA. The results showed that human coagulation factor VIII protein existed in culture medium with hFVIII:C up to 2.01 U/(10(6) cell x 24 hours) and hFVIII:Ag to 450.08 ng/(10(6) cell x 24 hours). RT-PCR displayed mRNA of hFVIIIBDcDNA in 32D cells. It is concluded that the recombinant plasmid RC/RSV-hFVIIIBDcDNA can successfully express human FVIII in mouse 32D cell line, and hFVIII expressed in vitro presents the similar coagulant activity to the native hFVIII existing in normal human plasma.

Animals↗

PubMed2004

[Clinical study of hemostatic coagulation markers in prethrombosis state of pregnancy induced hypertension].

OBJECTIVE: To investigate the relationship between the hemostatic coagulation markers of prethrombosis state and pregnancy induced hypertension (PIH). METHODS: Forty-five PIH patients and 20 control patients were studied. P-selectin, prothrombin fragments 1 + 2 (F1+2), D-dimers (D-D) and plasmin-antiplasmin complex (PAP) were measured by enzyme linked immunosorbent assay. Antithrombin activity (AT: A) was measured by chromogenic peptide substrate assay. RESULTS: (1) The P-selectin level of pre-delivery in moderate and severe PIH patients was (66 +/- 24) microg/L and (80 +/- 30) microg/L, it was (49 +/- 15) microg/L in the control group (both P < 0.05). The P-selectin level of post partum in severe PIH group and control group was (65 +/- 34) microg/L and (40 +/- 12) microg/L, with significant difference between them (P < 0.05). (2) The F1+2 level of pre-delivery in mild, moderate and severe PIH groups was respectively (2.2 +/- 0.2), (2.3 +/- 0.4) and (2.2 +/- 0.2) nmol/L, being all significantly higher than that in the control group, which was (1.2 +/- 0.3) nmol/L, but there was no obvious difference between three PIH groups. (3) The D-D level in mild, moderate and severe PIH groups was respectively (0.7 +/- 0.1), (0.7 +/- 0.3) and (0.8 +/- 0.2) mg/L, and it was (0.4 +/- 0.1) mg/L in the control group. The D-D level was increased when PIH became severe. (4) The PAP level in moderate and severe PIH groups was (0.8 +/- 0.4) mg/L and (0.8 +/- 0.4) mg/L, being significantly higher than that in control group (0.7 +/- 0.3) mg/L (both P < 0.05). (5) The AT: Aactivity was obviously decreased in PIH groups, being respectively (44 +/- 37)%, (64 +/- 25)% and (83 +/- 39)% in severe, moderate and mild PIH groups. There was obvious difference between severe and mild groups (P < 0.01). CONCLUSIONS: Elevated P-selectin levels and increased platelet activity were observed in PIH patients. F1+2 may be useful as a screening test for risk pregnancy. D-D can be used as an early monitor of DIC. AT: A reflects the severity of illness. These molecular markers may be used to predict the prethrombosis state in PIH.

Adult↗

PubMed2004

[Clinical study of hemostatic molecular markers expression in patients with cancer].

OBJECTIVE: To study the changes of hemostatic molecular markers in patients with gastric or intestinal cancer for elucidating their clinical significance. METHODS: The plasma levels of tissue factor (TF), thrombin antithrombin complex (TAT), tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), urokinase plasminogen activator receptor (u-PAR) and plasmin antiplasmin complex (PAP) were measured by ELISA. Gene transcription of TF, t-PA, u-PA mRNA were detected by real-time RT-PCR. RESULTS: The plasma levels of TF, TAT, u-PA, u-PAR and PAP were elevated in gastric or intestinal cancer patients (P < 0.05), while u-PA, u-PAR remarkably increased in patients with local infiltration, lymph node involvement or distal metastasis (P < 0.01). Plasma level of TF, TAT, PAP were remained higher than control even after surgery. TF, u-PA mRNA were higher (P < 0.01) and t-PA was lower (P > 0.05) in gastric or intestinal cancer compared to normal tissue. CONCLUSIONS: Their existed over expression of TF and u-PA, increasing formation of thrombin and plasminogen in gastric or intestinal cancer patients. Hypercoagulability and hyperfibrinolysis were important factors related with metastasis potential of gastric or intestinal cancer. t-PA may be a character of well differentiated tissue. Quantitative detection of TF and u-PA gene expression by the method of real-time RT-PCR is feasible for them as observation markers in gastric or intestinal cancer patients.

Adult↗

PubMed2004

Cloning and expression of vacA gene fragment of Helicobacter pylori with coccoid form.

BACKGROUND: Helicobacter pylori (H. pylori) can transform, in vivo as well as in vitro, from dividing spiral-shaped forms into nonculturable coccoid forms, whose importance in disease transmission and antibiotic treatment failures is unclear. The aim of the present study was to clone and express the vacA gene of coccoid H. pylori and to infer its possible pathogenesis. METHODS: Firstly, coccoid form was obtained from strain NCTC 11637 by exposure to antibiotics in subinhibitory concentrations and collected. Secondly, vacA gene of the coccoid H. pylori was amplified by PCR. After being purified, the target fragment was cloned into plasmid pMD-18T, and the recombinant plasmid pMD-18T-vacA was transformed into E. coli JM109. The sequence of inserted fragment was analyzed. Thirdly, vacA gene from recombinant plasmid pMD-18T-vacA was digested with restriction enzyme and was inserted into expression vector pET32a (+). The positive recombinants were transferred into E. coli BL21 and identified by restriction enzyme digestion and PCR. Finally, the genetically engineered bacteria including pET32a (+)-vacA plasmids were induced by IPTG, the expression was analyzed by SDS-PAGE and gel densitometric scanning. RESULTS: The results revealed that vacA gene of 3888bp was obtained from the coccoid H. pylori genome DNA, recombinant plasmid pMD-18T-vacA constructed were successfully digested by BamH I +Sac I, and the product of digestion was identical with the predicted 1. Sequence analysis also showed that the homology of coccoid and the reported original sequence was 99.8%. Plasmid pET32a (+)-vacA could express a specific 156kDa protein in E. coli BL21, and the protein accounted for 15.5% of the total protein of recombinant bacterial. CONCLUSIONS: The present data indicate that coccoid H. pylori contains complete vacA gene, and could synthesize its protein, which may be related to the disease relapse and transmission when coccoid H. pylori recovers virulence under suitable conditions.

Bacterial Proteins↗

PubMed2003

Detection of serum anti-Helicobacter pylori immunoglobulin G in patients with different digestive malignant tumors.

AIM: To investigate the seroprevalence of Helicobacter pylori infection in patients with different digestive malignant tumors. METHODS: Enzyme linked immunosorbent assay (ELISA) was used to detect serum anti-Helicobacter pylori IgG antibody in 374 patients with different digestive malignant tumors and 310 healthy subjects (normal control group). RESULTS: The seroprevalence of Helicobacter pylori infection was 61.50% (230/374) and 46.77% (145/310), respectively, in patients with digestive tumors and normal controls (P<0.05). The seroprevalence was 52.38% (33/63), 86.60% (84/97), 83.14% (84/101), 45.24 (19/42), 51.13% (18/35) and 44.44% (16/36), respectively in patients with carcinomas of esophagus, stomach, duodenum, rectum, colon and liver (P<0.01). In patients with intestinal and diffuse type gastric cancers, the seroprevalence was 93.75% (60/64) and 72.73% (24/33), respectively (P<0.05). In patients with gastric antral and cardiac cancers, the seroprevalence was 96.43% (54/56) and 73.17% (30/41), respectively (P<0.05). In patients with ulcerous and proliferous type duodenal cancers, the seroprevalence of H pylori infection was 91.04% (61/67) and 52.27% (23/44), respectively (P<0.05). In patients with duodenal bulb and descending cancers, the seroprevalence was 94.20% (65/69) and 45.20% (19/42), respectively (P<0.05). CONCLUSION: H pylori infection is associated with occurrence and development of gastric and duodenal carcinomas. Furthermore, it is also associated with histological type and locations of gastric and duodenal carcinomas.

Adult↗

PubMed2003

Detection of T lymphocyte subsets and mIL-2R on surface of PBMC in patients with hepatitis B.

AIM: To study the levels of T lymphocyte subsets and membrane interleukin-2 receptor (mIL-2R) on surface of peripheral blood mononuclear cells (PBMCs) of patients with hepatitis B and its role in the pathogenesis of hepatitis B. METHODS: The levels of T lymphocyte subsets and mIL-2R in PBMC before and after being stimulated with PHA were detected by biotin-streptavidin (BSA) technique in 196 cases of hepatitis B. RESULTS: In patients with hepatitis B, the levels of CD(3)(+), CD(4)(+) cells, and the ratio of CD(4)(+) cells/CD(8)(+) cells were lower, but the level of CD(8)(+) cells was higher than those in normal controls (42.20+/-6.01 vs 65.96+/-6.54, 38.17+/-5.93 vs 41.73+/-6.40, 0.91+/-0.28 vs 1.44+/-0.31, 39.86+/-6.36 vs 30.02+/-4.54, P<0.01). The total expression level of mIL-2R in PBMC before and after being stimulated with PHA was also lower than those in normal controls (3.47+/-1.55 vs 4.52+/-1.49, 34.03+/-2.94 vs 37.95+/-3.00, P<0.01). In all the patients with hepatitis B, the levels of T lymphocyte subsets and mIL-2R in PBMC with HBV-DNA (+) were lower than those with HBV-DNA (-), which were significantly different (39.57+/-7.11 vs 44.36+/-5.43, 34.36+/-7.16 vs 40.75+/-5.87, 37.82+/-6.54 vs 41.72+/-6.21, 0.88+/-0.33 vs 0.99+/-0.27, 2.82+/-1.62 vs 3.85+/-1.47, 31.56+/-3.00 vs 35.84+/-2.83, P<0.01). In addition, the levels of CD(3)(+), CD(4)(+), CD(8)(+) cells, the ratio of CD(4)(+) cells /CD(8)(+) cells and mIL-2R among different courses of hepatitis B were all significantly different (F=3 723.18, P<0.01. F=130.43, P<0.01. F=54.01, P<0.01. F=2.99, P<0.05. F=7.16, P<0.01). CONCLUSION: Both cellular and humoral immune functions are obviously in disorder in patients with hepatitis B, which might be closely associated with the chronicity in patients.

Acute Disease↗

PubMed2002

Interleukin-1beta expression on ovarian granulosa cells and its clinical implication in women undergoing in vitro fertilization.

OBJECTIVE: To detect the expression of interleukin-1beta (IL-1beta) on the surface of human luteinized granulosa cells and to understand its relation to the hormones in human follicular fluid and sera. METHODS: Thirty-six women receiving in vitro fertilization-embryo transfer (IVF-ET) were enrolled in this study. The luteinizing granulosa cells were recovered from the follicular fluid obtained during transvaginal ultrasound-guided oocyte retrieval for IVF-ET. Flow cytometry was employed to detect the expression of IL-1beta on human granulosa cells, and the concentrations of IL-1beta and the hormones in the follicular fluid were measured by enzyme-linked immunosorbent assay. RESULTS: IL-1beta was detected in the follicular fluid of women with IVT-ET and in the luteinizing granulosa cells. A positive correlation was observed between the sera concentrations of IL-1beta and estradiol on the day when human chorionic gonadotrophin (hCG) was injected (r=0.92, P<0.001), while on the same day the concentration of IL-1beta was shown to be inversely correlated with progesterone levels (r=-0.34, P<0.05). CONCLUSION: IL-1beta in the follicular fluid comes not only from plasma ultrafiltrate but also from luteinizing granulosa cells. The inhibition of progesterone production by luteal cells in the presence of IL-1beta may be one of the factors resulting in the failure of implantation.

Adult↗

PubMed2002

[Sperm-mediated expression of human clotting factor VIII gene in transgenic offspring of mice].

The expression of human clotting factor VIII gene was observed in transgenic off spring of mice through artificial insemination with sperm as carriers. Female mice were impregnated through artificial insemination by introducing sperm carrying pRC/RSV-hF VIII BD, which contained human F VIII BD (B-domain deleted) cDNA (hF VIII BD c DNA), into the uteri. During the fourth week after the birth of new-born mice, PCR was used to screen hF VIII BD cDNA positive transgenic mice, then blood of which was collected for detecting the antigen and Anti-hF VIII inhibitors, simultaneously, the transcription and expression of hF VIII BD cDNA were investigated by Northern blot and Western blot. The results showed that 7 became pregnant of 20 inseminated mice, and 11 new-born mice came into the world, out of which 9 survived at last. Three hF VIII BD cDNA-positive-transgenic mice had been screened out by PC R, in which the antigen of human F VIII in plasma was 8.65 ng/ml, 7.84 ng/ml and 8.44 ng/ml, respectively, the Anti-hF VIII inhibitors were all negative. Northern blot and Western blot showed that the transcription and expression of hF VIII BD cDNA existed in tissues such as spleen, liver, lung and kidney of 3 transgenic mice. It was concluded that transgenic mice carrying human F VIII gene can be generated by sperm-carrier techniques and express human F VIII protein. This experiment provides important data for manufacturing transgenic animal carrying human F VIII gene, which can work as a biological reactor to produce human F VIII protein, through sperm-carrier techniques.

Animals↗