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Wei Liu

Publications and source records attributed to Wei Liu.

At least 145 records · Page 8Linked to original sources
PubMed2006

[Effect of adeno-BMP7 transfection on osteogenesis of BMSCs].

OBJECTIVE: To study the effect of adeno-BMP7 transfection on the biology of bone marrow stromal cells (BMSCs). METHODS: Bone marrow was obtained from the goat. The BMSCs were isolated and cultured at the second passage. Once the cells attached and formed a monolayer with 70%-80% confluency, adeno-BMP7 (M.O.I. = 100) was added to the cells. After three days, calcium node was examined with staining; cell-coral compound was replanted subcutaneously. RESULTS: With adeno-BMP7 transfection, BMP7 expression was detected with Western-blot; big calcium nodes were observed with staining. New bone formation was enhanced, which was evaluated by X-ray and histological examinations. CONCLUSIONS: BMSCs transfected with adeno-BMP7 show much stronger osteogenic ability.

Adenoviridae↗
PubMed2006

Abnormal activation of the synuclein-gamma gene in hepatocellular carcinomas by epigenetic alteration.

Liver cancer is the fifth most common neoplastic disease and the fourth leading cause of cancer-related death. Identification of the key molecular targets involved in hepatocarcinogenesis has significant therapeutic implications. In this study, by conducting immunohistochemistry, we show that the neuronal protein, synuclein-gamma (SNCG), is abnormally expressed in a high percentage of liver cancer (46/70, 65.7%). The expression of SNCG in liver cancer exhibits a clear stage-specific pattern of low expression in stage I (1/19, 5.3%) and high expression in stages III to IV (44/50, 88%). Importantly, all patients with metastatic diseases expressed SNCG in their primary tumors (15/15, 100%). Consistent with the IHC results, RT-PCR assays demonstrate that SNCG mRNA is highly expressed in the tumor tissue of advanced hepatocellular carcinomas. Analyses of the methylation status of the CpG island of the SNCG gene by methylation-specific PCR confirmed that all tumor samples contained the demethylated gene. To determine whether demethylation of SNCG is an early event of genetic abnormality in the process of hepatocarcinogenesis, we examined the methylation status of SNCG in 70 non-malignant cirrhotic liver samples and showed that 64.3% cirrhotic liver samples contained the partially or completely demethylated gene. We further show that SNCG expression in liver cancer is not restricted to HBV- and HCV-infected tumors, implying the involvement of other hepatocarcinogenic risk factors in SNCG gene reactivation. Utilizing human hepatoma-derived cell line HepG2 as an in vitro model, we demonstrate that hepatic carcinogens aflatoxin B1 and N-nitrosodimethylamine (DMN) are strong inducers of SNCG expression. Collectively, these new findings suggest that SNCG protein expression in primary tumors is a strong indicator of distant metastasis and demethylation of SNCG CpG island is an early sign of genetic abnormality in liver cirrhosis preceding hepatocarcinogenesis. Our studies also suggest that inducing demethylation of SNCG by hepatocarcinogens may represent one underlying mechanism for the aberrant expression of SNCG in HCC.

Adult↗
PubMed2006

[The research on associating the single nucleotide polymorphism of CTLA-4 gene promoter region with idiopathic dilated cardiomyopathy].

OBJECTIVE: To investigate the expression of cytotoxic T lymphocyte associated antigen-4 (CTLA-4) in patients with idiopathic dilated cardiomyopathy (IDC) and to explore genetic susceptibility to IDC caused possibly by single nucleotide polymorphism (SNP) of CTLA-4 gene promoter. METHODS: PCR-restriction fragment length polymorphism techniques were used to analyze the SNPs of CTLA-4 gene at position -1772, -1661 and -318 in the promoter region. Serum sCTLA-4, IFN-gamma and IL-4 were tested by ELISA. RESULTS: sCTLA-4 levels of IDC patients were associated with the haplotype and genotype. Patients with -1772 TC genotype or -1772 TC -1661 AA, -1772 TC -1661 AG haplotypes had higher sCTLA-4 levels than patients with other haplotypes did. The frequency of -1772 TC genotype was significantly high in patients with low ejection factor(EF) values. Whereas the frequencies of -1661 G allele and -1661 GG genotype were lower in IDC patients. Levels of IL-4 were increased in IDC group. CONCLUSION: Patients with IDC have an aberrant expression of the CTLA-4 products, and the -1772 C/T and -1661 A/G polymorphisms. The two SNPs may function as genetic markers for disease susceptibility.

Antigens, CD↗
PubMed2006

[Experimental study of pristane-induced murine lupus model].

OBJECTIVE: To establish a mouse model of systemic lupus erythematosus(SLE) and to discuss the role of environmental factors in the pathogenesis of SLE. METHODS: Thirty 10-week-old female BALB/c mice were divided into the model group and control group. The model mice received a single intraperitoneal injection of 0. 5 mL of pristane, while control mice received a single i.p. injection of 0. 5 mL of 0.9% NS. Autoantibodies and proteinuria were detected before injection and monthly thereafter. 8 months after injection, all mice were bled to death. Kidneys were excised to observe the histopathologic evidence of glomerulonephritis. RESULTS: After pristane injection, antinuclear antibody(ANA) and anti-dsDNA antibody appeared in sera as early as 3 months and 4 months respectively. At 8 months, the incidence rates of ANA and anti-dsDNA antibody were 87.5% and 47.8% respectively. The protein concentration of urine in most mice was > or =1+ (300 mg/L). Light microscopy and immunofluorescence of kidney sections indicated glomerulonephritis. In control group, only one serum was ANA low-titer positive and another was anti-dsDNA antibody low-titer positive. The protein concentration of urine was < or = 1+. The histopathology and immunofluorescence showed no evidence of glomerulonephritis. Spearman correlation analysis indicated that anti-dsDNA antibody was correlated with proteinuria (r = 0.538, P = 0.003). CONCLUSION: The murine lupus model can be successfully established in female BALB/c mouse with a single i. p. injection of 0. 5 mL of pristane and the specific autoantibody anti-dsDNA for SLE has appeared in sera of BALB/c mice.

Animals↗
PubMed2006

[Correlation of intestinal mucosal injury with serum diamine oxidase].

OBJECTIVE: To study the relationship between the changes of intestinal mucosal tumor necrosis factor alpha (TNF-alpha), plasma diamine oxidase (DAO) values and the degree of mucosal injuries in young rat model of colitis and thereby to explore if plasma DAO could be used as a potential index for monitoring intestinal mucosal injury. METHODS: One hundred and four healthy young male Sprague-Dawley (SD) rats aged 5-6 weeks were randomly divided into three groups: zero time group (n = 8), model group (n = 48) and control group (n = 48). The model and control groups were further divided into 24 h, 72 h, 1 week, 2 weeks, 3 weeks and 4 weeks subgroups, respectively, with 8 rats in each. The rats in model group were given 2, 4, 6-trinitrobenzene sulfonic acid (TNBSA) via enema to induce colitis, while the rats in the control group were given normal saline (NS) solution in the same way and those in zero time group were not treated. TNF-alpha and DAO were measured by immunohistochemical technique and spectrophotometry. RESULTS: The most serious enteric mucosal injury was seen 24 hours after giving TNBSA. Plasma DAO and TNF-alpha decreased as the intestinal mucosal injury was alleviated. CONCLUSIONS: Plasma DAO values may be used as a marker for intestinal mucosal injury. TNF-alpha is a factor for causing mucosal injury. Young rat colitis model can be used to study intestinal mucosal injury.

Amine Oxidase (Copper-Containing)↗
PubMed2006

[Repair of canine segmental mandibular defects using autogenous bone marrow stromal cells and coralline hydroxyapatite].

OBJECTIVE: To repair segmental mandibular defects with autogenous bone marrow stromal cells (BMSCs) and coralline hydroxyapatite. METHODS: Isolated BMSCs were in vitro expanded and osteogenically induced. In 11 canines, a 3 cm segmental mandibular defect in right mandible was created. Five canine's defects were repaired with cell-scaffold constructs made from induced BMSCs and coralline hydroxyapatite (CHA); Others were repaired with CHA as control. The engineered bone was evaluated by X-ray, CT, gross and histological examination, biomechanical test 12, 26, 32 weeks post-operation respectively. RESULTS: BMSCs grew well on the CHA. X-ray and CT images showed better callus formation at connection sites in experimental group over time while worse formation at connection sites eventually in control group. At 32 weeks post-operation in experimental group, the defects were well repaired grossly. Histologically, there were bony healing and lamellar bone formation, in experimental group fibrous healing and woven bone formation in control group. Biomechanical test revealed no significant difference between experimental group and normal control group. CONCLUSIONS: Canine segmental mandibular defects can be ultimately repaired with the tissue-engineered bone generated by autogenous osteogenic BMSCs and CHA scaffold.

Animals↗
PubMed2006

[Studies on gene expression and the 5' CpG islands methylation status of E-cadherin in acute myeloid leukemia].

OBJECTIVE: To study the relationship between E-cadherin gene expression and the methylation status of E-cadherin 5' CpG islands in acute myeloid leukemia (AML). METHODS: Reverse transcription-PCR (RT-PCR), flow cytometry and methylation specific PCR were used to analyze the E-cadherin gene and protein expression and its 5' CpG island methylation status respectively in bone marrow cells from 55 AML patients and 7 normal controls. RESULTS: AML cells displayed a significant reduction or lack of E-cadherin gene and protein expression, the positive rates were 23.6% and 18.2% (P < 0.01), respectively. All normal bone marrow cells were E-cadherin positive. Thirty-eight of the 55 patients (69.1%) were E-cadherin 5' CpG island methylated whereas the normal controls were completely unmethylated. Twenty-nine of thirty-one (93.5%) E-cadherin-negative samples showed abnormal hypermethylation of the E-cadherin CpG islands. CONCLUSION: Expression downregulation and methylation of E-cadherin gene in AML suggest that it might be an important event in AML. E-cadherin methylation was associated with the inhibition of E-cadherin gene and protein expression in AML.

Cadherins↗
PubMed2006

[Recombinant eukaryotic expression plasmid of bcr-abl gene fragment induces specific immune response in mice].

OBJECTIVE: To study the specific immune response induced by a recombinant eukaryotic expression plasmid encoding bcr-abl fusion gene fragment so as to explore new immunotherapy in mouse. METHODS: A recombinant eukaryotic vector pVbcr-abl expression cDNA fragment of bcr-abl fusion gene was constructed and used to immunize BALB/c mice. Serum level of bcr-abl specific antibody was detected by enzyme-linked immunosorbent assay (ELISA). Twenty days later the immunized mice were subcutaneously inoculated SP2/0/bcr-abl cells. The survival time, tumor growth time and lymphocytic infiltration were observed. T cells infiltration into tumor tissue was analyzed by immunohistochemistry. Changes of T cell subset in the spleen of mice was analyzed by fluorescent-activated cell sorting (FACS) and the cytotoxicity T lymphocyte (CTL) activity in spleen by lactate dehydrogenase (LDH)-release assay. RESULTS: The eukaryotic expression vector pVbcr-abl was constructed successfully, and highly expressed the cDNA fragment of bcr-abl fusion gene. The BALB/c mice immunized with the vector could generate the specific antibody and CTL, resulting in a specific immunoprotection. There were dramatic differences in the tumor-forming time, tumor ulcer appearing time and tumor-growing speed between the immunized and the control groups. The mice had longer survival time in the immunized group than in the control group. There were a large amount of CD3(+) T cells infiltration in tumor tissue of the immunized mice. The spleen cells from the immunized mice had higher CTL activity with a alteration of T cell subset, the CD4(+)/CD8(+) ratio being 1.54 +/- 0.29, higher than that of control group (1.18 +/- 0.30). CONCLUSION: The recombinant eukaryotic expression plasmid pVbcr-abl can induce in vivo not only the generation of specific antibody, but also high level of specific CTL activity, resulting in killing the SP2/0/bcr-abl tumor cells directly and inhibiting the tumor growth.

Animals↗
PubMed2006

[Interventional treatment for occlusive lesions in supra-arch vessels with brain ischemic symptoms].

OBJECTIVE: To evaluate the therapeutic effect of percutaneous transluminal angioplasty and stenting for occlusive lesions in supra-arch vessels with brain ischemic symptoms. METHODS: A total of 56 occlusive lesions of the innominate, subclavian, and internal carotid arteries were treated with angioplasty and intravascular stent placement in 52 patients. The degree of stenosis was more than 60% in all patients and the leading symptom was brain ischemia. In 11 patients, the occluded subclavian artery could not be crossed via the femoral route, therefore the brachial route was used and the occlusion was crossed in a retrograde fashion. RESULTS: Technical success was achieved in 54 of 56 procedures (96.4%). Residual stenosis was less than 30% in all cases. The clinical symptoms improved after procedure in all patients. Complications occurred in 3 of 52 (5.8%) procedures, and the 30-day mortality rate was 0. There were no death and severe stroke in the follow-up period (means 24 months). Restenosis was observed in 2 patients after percutaneous transluminal angioplasty treatment. CONCLUSION: Percutaneous transluminal angioplasty with or without stenting is a safe and valid choice for treatment of occlusive lesions of supra-arch vessels in patients with cerebral ischemic symptoms.

Adolescent↗
PubMed2006

[The influence of abscisic acid treatment on desiccation tolerance in Dendrobium candidum protocorm-like bodies].

Effect of ABA on desiccation tolerance in the protocorm-like bodies (PLBs) of D. candidum was studied. The best result was obtained while ABA precultured at 5 micromol/L for 24 h (Fig.2). PLBs vitality rate was 10 times of the control after 2 h desiccation (Table 1). Detection of cytoplasmic osmoticums showed that ABA preculture could not induce the accumulations of soluble sugar, proline, etc (Tables 3, 4 and 7). But the content of soluble polysaccharide rose conspicuously (Table 5). So we think that the accumulation of soluble polysaccharide may play an important role in desiccation tolerance induced by ABA preculture.

Abscisic Acid↗
PubMed2006

[Simultaneous determination of heavy metal elements in footwear materials by ICP-AES].

Footwear materials were treated by the digestion method of carbonization-crack-HNO3-HClO4 dissolution, and the heavy metal elements in these materials were simultaneously determined in the same treated solution. Factors such as the selection of analytical wavelength and the interference of matrix and coexistent elements were studied. The method was secure, convenient, rapid and accurate. The recovery rates of the procedure were between 92.0% and 102.0% with RSDs between 1.0% and 4.6%.

English Abstract↗
PubMed2006

[Isolation, identification of lignin-degrading bacteria and purification of lignin peroxidase].

Two strains that could use lignin as sole carbon source and excrete peroxidases were isolated from activated sludge. Both strains are belonged to Pseudomanas based on morphological, physio-biochenical characterizatics and homology identification of 16S rDNA sequence, in which strain PKE117 is identified as a new species, while the strain PKE225 is identified as Pseudomanas thermaerum. Crude enzyme in liquid fermentation of PKE117 was analyzed with DEAE-cellulose 32 ion-exchanger resin chromatography and Sephadex G-75 gel-filtration in proper order. The lignin peroxidase specific activity increases from 0.87 U/mg to 204.5 U/mg, purification multiple is 235.1 and callback rate is 15%.

Lignin↗
PubMed2006

[Clinical observation on treatment of active systemic lupus erythematosus with haoqin qingdan decoction].

OBJECTIVE: To observe the therapeutic efficacy and safety of Haoqin Qingdan Decoction (HQD) in treating active stage of systemic lupus erythematosus (SLE). METHODS: One hundred and twenty patients with SLE were randomly assigned into two groups, the treated group receiving HQD and prednisone, and the control group receiving prednisone and cyclophosphamide (CTX), both were treated for 3 months. SLE disease activity index (SLEDAI), various immunological indexes, blood and urine routine, hepatic and renal function, as well as the other adverse reaction of the treatment were observed. RESULTS: The total effective rate in the treated group was 81.67% (49/60), while 76.67% (46/60) in the control group, showing insignificant difference between the two groups. SLEDAI, erythrocyte sedimentation rate (ESR), complement 3 (C3), 24-hr urinary protein excretion and anti-double strain deoxyribonucleic acid (dsDNA) antibody were improved in the treated group, and no obvious adverse reaction was shown. CONCLUSION: HQD is obviously more effective in treating active stage of SLE with high safety.

Adolescent↗
PubMed2006

[Influences of bcr-abl gene vaccine on inoculated SP2/0/bcr-abl tumor cells in mice].

To study the influence of vaccine of bcr-abl fusion gene fragment on inoculated SP2/0/bcr-abl tumor cells in mice, BALB/c mice were immunized with pVbcr-abl, pVbcr-abl/mIL7 plasmids, respectively, then SP2/0/bcr-abl cells expressing the fragment of bcr-abl fusion gene were inoculated subcutaneously into the groin of BALB/c mice in order to observe the effect of vaccine on growth of inoculated SP2/0/bcr-abl tumor cells. The results showed that there were distinct differences on the time of tumor growth, the time of tumor ulceration, tumor volume and survival time of mice bearing tumor between two immunized groups and two control groups (blank and vacant plasmid groups). The mice immunized with pVbcr-abl/mIL7 lived longer as compared to mice immunized with pVbcr-abl. The tissue of inoculated tumor was more compact, tumor organ was larger, tumor form was irregular in 2 control groups, while the tissue of inoculated tumor was looser, tumor volume was smaller, and with mass inflammatory infiltration in two immunized groups. Moreover, the metastatic tumor cells were found in the livers of control groups, but not observed in two immunized groups. It is concluded that the protection occurred in immunized mice which inhibited the growth of SP2/0/bcr-abl tumor cell in vivo.

Animals↗
PubMed2006

[In vitro study on proliferation and multi-lineage differentiation potential of adipose-derived cells].

Adipose were obtained from patients underwent liposuction treatment (total 19 female donors, 31.5 +/- 5.8 years old). Liposuction tissues were digested with type I collagenase, cells were isolated and cultured up to passage 10. To evaluate the proliferation potential of ADCs, growth curve and cumulative population doubling were achieved by cell counting. CD29,CD105, CD106, CD166, CD49d, CD34, CD31, 3G5 were analyzed by flow cytometry and immunocytochemistry to characterize the cell population. The multi-lineage potential of ADCs was testified by differentiating cells with osteogenic,chondrogenic and adipogenic inducer. A total of 5x10(7) nucleared cells could be obtained from 300ml liposuction tissues. After in vitro cultivation,cumulative population doubling number reached 15.53 at passage 10 (average 1.59 +/- 0.224 /passage). Flow cytometry and immunocytochemistry showed that ADCs expressed high level (>60%) of stem cell-related antigen (CD29, CD105, CD106, CD166), while cells expressed hematopoiesis-related antigen CD34 and CD31 around 7.3% and 29.2% respectively. Collagen II (both in mRNA and protein level) was detected in chondrogenic differentiation. The calcified nodules were observed by von Kossa and Alizarn Red staining and the expressions of AKP and Osteonectin were detected by RT-PCR in osteogenic differentiation. PPARr2, GLU-4, and Leptin genes were detected in adipogenic differentiation and intracellular lipid droplets could be observed by Oil Red staining. ADCs can be abundantly harvested and have high proliferative and multi-lineage differentiation potential.

Adipocytes↗
PubMed2006

[Ultrasonic bone mineral density of calcaneus in 1 816 healthy subjects in Guangxi autonomous region].

OBJECTIVE: To study the relationship between ultrasonic bone mineral density (BMD) of calcaneus and age, height, and body weight, and to establish the normal reference value for stiffness index (SI) of healthy subjects in Guangxi autonomous region and provide scientific foundation for the diagnosis and prevention of osteoporosis. METHODS: SI of calcaneus in 1 816 healthy adults aged 11-90 years (775 men, 1 041 women) were measured with quantitative ultrasound. According to their ages, all the men and women were divided into 13 groups by 5-year age group. RESULTS: SI reached peak values in 21-25 year group in men (range: 111.45 +/- 21.19) and in 16-20 year group in women (range: 101.26 +/- 17.51). Then the SI value began to decline with aging. The SI featured by a typical dual-peak curve in women and the decrease rate of SI was faster in women than in men over 61 years. Multivariate linear regression analysis showed significantly negative correlation between SI and age (P < 0.001), positive correlation between SI and body weight (P < 0.05 for men; P < 0.01 for women), and positive correlation between SI and height in women (P < 0.01). CONCLUSION: SI correlates with age, height, and weight. The acquired SI value may provide a reference for the diagnosis of osteoporosis.

Adolescent↗