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Ting Liu

Publications and source records attributed to Ting Liu.

At least 55 records · Page 3Linked to original sources
PubMed2005

[Effect of formaldehyde on energy metabolism in postnatal rat cortex neurons in culture].

OBJECTIVE: The mechanism of the effect of formaldehyde on CNS which is much concerned to formaldehyde poisoning was studied. METHODS: In the present study, incubation of postnatal rat cortex neurons in culture with formaldehyde at 1, 2, 4, 8 mg/L (medium) was carried out to evaluate the effect of formaldehyde on energy metabolism. RESULTS: The result of cytochemistry showed a significant down-regulation of cytochrome oxidase activity after consecutive formaldehyde treatment for 4 hours compared with the control (P < 0.01), the significant dosage-response relationship was also observed (R value is - 0.92, P < 0.01). CONCLUSION: The result demonstrates that excessive exposure of formaldehyde can decrease cytochrome oxidase activity in cortex neurons which indicates energy metabolism will be decreased and therefore normal physiology function would be damaged.

Animals↗
PubMed2005

[Immune regulatory effect of human bone marrow mesenchymal stem cells on T lymphocyte].

To investigate the immune regulatory effects of human bone marrow mesenchymal stem cells on alloantigen T lymphocyte in vitro, human MSCs were isolated and expanded from bone marrow cells, and identified with cell morphology, and the phenotypes were assessed by immunohistochemistry and flow cytometry. As the stimulation factor of T lymphocytes proliferation, either PHA or dendritic cells isolated from cord blood were cocultured with CD2(+) T lymphocytes from peripheral blood mononuclear cells by magnetic beads with or without MSC in 96-well plats for seven days. T cell proliferation was assessed by [(3)H]-thymidine incorporation using a liquid scintillation counter. T cell subsets, Th1, Th2, Tc1 and Tc2 were analyzed by flow cytometry after co-culture of CD2(+) T cells with MSCs for 10 days. The results showed that a significant decrease of CD2(+) T cell proliferation was evident when MSC were added back to T cells stimulated by DC or PHA, and an increase of Th2 and Tc2 subsets were observed after co-culture of MSC with T lymphocytes. It is suggested that allogeneic MSC can suppress T cell proliferation in vitro and the cause of that was partly depend on interaction of cells and the alteration of T cell subsets.

Bone Marrow Cells↗
PubMed2005

[Relationship of mitochondrial DNA mutation with myelodysplastic syndromes - review].

Myelodysplastic syndromes are refered to as a group of diseases characterized by abnormal clonal proliferation of hematopoietic stem cells with pancytopenia and dysplasia. Recently, it has been documented that ringed sideroblasts are not only confined to the refractory anemia with ring sideroblast (RARS) subtype of MDS, but also contribute to numerous underlying MDS pathophysiological processes as a significant feature of dysplasia. This clonal heterogeneity suggested a pathogenetic role of mitochondrial DNA mutation. Many studies have shown that mitochondrial respiratory chain defects resulting from mutation of mitochondrial DNA may lead to multiple pathophysiologic changes, and may impact on the pathogeneses of MDS.

Apoptosis↗
PubMed2005

[Expression of KAI1, MRP-1, and FAK proteins in lung cancer detected by high-density tissue microarray].

BACKGROUND & OBJECTIVE: The genesis, development, invasion, and metastasis of tumor are closely correlate with alterations of multi-genes. At present, the roles of Kang-ai-1 (KAI1), motility-related protein-1 (MRP-1), and focal adhesion kinase (FAK) in lung cancer have seldom been reported. This study was designed to investigate the roles of KAI1, MRP-1, and FAK in tumorigenesis and development of lung cancer, and their values in diagnosis and predicting the prognosis of lung cancer. METHODS: The expression of KAI1, MRP-1, and FAK proteins in a high-density tissue microarray containing 240 spots were detected by SP immunohistochemistry. RESULTS: The positive rates of KAI1 and MRP-1 were significantly lower in primary lung cancer than in normal lung tissue (25.9% vs. 100%, 42.6% vs. 100%, P<0.05). The positive rate of FAK was significantly higher in primary lung cancer than in normal lung tissue (44.4% vs. 10.0%, P<0.05). The expression of KAI1, FAK, and MRP-1 in primary lung cancer had no correlation with age and gender of the patients, and macroscopic and histological type of tumor, but had correlations with tumor differentiation, clinical stage, and lymph node metastasis. In addition, the expression of MRP-1 had correlation with histological type of tumor; the positive rate of MRP-1 was significantly lower in small cell lung cancer than in non-small cell lung cancer (0 vs. 50.0%, P<0.05). KAI1 expression was negatively correlated to FAK expression (rs=-0.458, P<0.05); MRP-1 expression was positively correlated with KAI1 expression (rs=0.535, P<0.05), and negatively correlated with FAK expression (rs=-0.438, P<0.05). CONCLUSIONS: The abnormal expression of KAI1, MRP-1, and FAK proteins are related to invasion and metastasis of lung cancer. Combined detection of the 3 proteins may be useful in predicting the development and prognosis of lung cancer.

Adult↗
PubMed2005

[Antitumor effect of recombinant Xenopus laevis vascular endothelial growth factor (VEGF) as a vaccine combined with adriamycin on EL4 lymphoma in mice].

OBJECTIVE: To explore the antitumor effect of immunotherapy with recombinant Xenopus laevis vascular endothelial growth factor (xVEGF) as a vaccine combined with adriamycin on lymphoma model in mice. METHODS: EL4 lymphoma model was established in C57BL/6 mice. Mice were randomized into four groups: combination therapy, adriamycin alone, xVEGF alone and normal saline (NS) groups, and then were given relevant treatments. The growth of tumor, the survival rate of tumor-bearing mice, and the potential toxicity of regimens above were observed. Anti-VEGF antibody-producing B cells (APBCs) were detected by enzyme-linked immunospot (ELISPOT) assay. In addition, microvessel density (MVD) of tumor was detected by immunohistochemistry, and tumor cell apoptosis was also detected by TUNEL staining. RESULTS: The tumor volumes of mice were significantly smaller in combination group than those in other three groups (P < 0.05). Complete regression of tumor was observed in 3 of 10 mice in combination group. Forty-eight days after inoculation of tumor cells, the survival rate of mice was significantly higher in combination group than in NS group (P < 0.01). The anti-VEGF APBC count in combination group or xVEGF group was significantly higher, compared with that in adriamycin group or NS group (P < 0.01). MVD in tumor tissues was significantly lower in combination group than those in other three groups (P < 0.05). Moreover, tumor cell apoptosis was significantly higher in combination group than those in other three groups (P < 0.05). CONCLUSION: In this experimental study, the use of xVEGF vaccine and adriamycin as a combination of immunotherapy with chemotherapy has sucessfully produced synergistic antitumor effect on lymphoma in mice.

Animals↗
PubMed2005

Expression and significance of Survivin mRNA in lung cancer tissue microarray detected by FISH.

OBJECTIVE: To investigate the expression of Survivin mRNA in lung cancer tissue microarray (TMA) by fluorescence in situ hybridization (FISH) method, and determine the role and significance of it in lung cancer genesis and progress. METHODS: The expression of Survivin mRNA was detected by FISH method and TMA technology. Fifty-four cases of lung cancer and 10 cases of normal lung tissue were examined. RESULTS: Survivin mRNA was expressed in 66.7% (36/54) of lung cancer; the positive ratio of lung cancer was significantly higher than that of normal lung tissue (0/10; chi2 = 15.238, P < 0.05). The positive ratio of Survivin mRNA was significantly higher in poor differentiated cancer (20/24, 83.3%) than moderate and well differentiated cancer (16/30, 53.3%; chi2 = 5.40, P < 0.05). The positive ratio of Survivin mRNA was significantly higher in group with lymph node metastasis (27/32, 84.4%) than without lymph node metastasis (9/22, 40.9%; chi2 = 11.084, P < 0.05). The positive ratio of Survivin mRNA was significantly higher in stage III-IV(12/13, 92.3%) than stage I - II (24/41, 58.5%; chi2 = 5.066, P < 0.05). CONCLUSION: Survivin mRNA highly expresses in lung cancer, which is related to the progress and malignant behavior. Survivin may play a promoting role in lung cancer genesis and progress and provide a basis for estimating prognosis and treatment.

Adenocarcinoma↗
PubMed2005

[Oriented immobilization of papain on metal chelating carriers].

Based on the technology of protein separation with immobilized metal ion affinity chromatography (IMAC), a method for oriented immobilization of papain has been selected. Papain was successfully immobilized on magnetic agarose carriers. Cu2+ with iminodiacetate (IDA) was used as the chelating ligand to be correlated with the histidine on papain (His-81). The optimum immobilization conditions of enzyme were as flows: Cu2+ 0.15 x 10(-2) mol/g carriers, time was 4h, enzyme load was 30 mg/g carrier, pH was 7.0, respectively. The pH and temperature were 8.0 and 70 degrees C for immobilized enzyme. The recovery activity of immobilized enzyme was retained 68.4%. The carrier could be recovered from the spent immobilized enzyme, to be reused. After 5 times, the reimmobilization of papain on the regenerated matrix was 79.71% effective with the retention of maximum enzyme activity. The cost of carriers used for industrial applications is very important. The regenerability of carriers is therefore, relevant. The mild conditions used for immobilization, the high recovery of immobilized preparations, the stability and the regenerability of the matrix are the main features of the method reported here. All above indicate this method can be applicable and promising in enzyme immobilization field.

Catalysis↗
PubMed2005

[Comparison between R-CHOP regimen and CHOP regimen in treating naive diffuse large B-cell lymphoma in China--a multi-center randomized trail].

BACKGROUND & OBJECTIVE: CHOP regimen is a standard treatment for patients with diffuse large B-cell non-Hodgkin's lymphoma (NHL), and its 5-year overall survival (OS) rate is 30%-40%. Rituximab is a chimeric monoclonal antibody (MoAb) directly against CD20-positive B cells, and has good effect on diffuse large B-cell NHL. Rituximab combined with standard chemotherapy has been approved for treating aggressive B-cell NHL in Europe and the US. This study was to determine efficacy and safety of the combination of Rituximab and CHOP regimen in treating Chinese patients with CD20-positive diffuse large B-cell NHL. METHODS: From Sep. 2003 to Nov. 2004, a total of 63 patients in 9 centers were enrolled. All the patients were randomized into 2 groups: 32 received CHOP regimen alone (CHOP group), and 31 received Rituximab and CHOP regimen (R-CHOP group). All patients signed informed consent. The complete response rates, overall response rates, and side events of the 2 groups were compared. RESULTS: The complete response rates were similar in R-CHOP and CHOP groups (41.9% vs. 37.5%, P=0.719); the overall response rates were slightly higher in R-CHOP group than in CHOP group (83.8% vs. 65.6%, P=0.096). Disease progression during treatment was reported for 7 (21.9%) patients in CHOP group and 1 (3.2%) patient in R-CHOP group (P=0.026). The occurrence rates of adverse events were similar in R-CHOP and CHOP groups (65.6% vs. 67.7%, P=0.859). The most common adverse event was leukopenia; fever and chills were rather common in R-CHOP group. Clinically relevant toxicity was similar in both groups. CONCLUSION: When compared with standard CHOP alone, the addition of Rituximab to standard CHOP regimen reduces the risk of treatment failure in patients with diffuse large B-cell NHL, and doesn't increase the occurrence of chemotherapy-related adverse events.

Adolescent↗
PubMed2004

ZNF216 Is an A20-like and IkappaB kinase gamma-interacting inhibitor of NFkappaB activation.

The transcription factor NFkappaB plays important roles in immune regulation, inflammatory responses, and anti-apoptosis. Activation of NFkappaB requires the activity of IkappaB kinase, a kinase complex that contains two catalytic subunits, IKKalpha and IKKbeta, and a non-enzymatic regulatory subunit, IKKgamma. To understand how NFkappaB activation is regulated at the IKKgamma level, we searched for IKKgamma-interacting proteins by the yeast two-hybrid system. This search identified ZNF216, a zinc finger protein with unknown biological functions. ZNF216 contains an A20-like zinc finger domain (ZnF-A20) at its N terminus and an AN1-like domain (ZnF-AN1) at its C terminus. Similar to A20, ZNF216 interacted with IKKgamma, RIP, and TRAF6 in co-immunoprecipitation experiments. Domain mapping experiments indicated that the ZnF-A20 domain was responsible for interacting with IKKgamma and RIP, whereas the ZnF-AN1 domain interacted with TRAF6. ZNF216 inhibited NFkappaB activation triggered by overexpression of RIP and TRAF6 but not of p65. ZNF216 also inhibited tumor necrosis factor (TNF)-, interleukin-1-, and Toll-like receptor 4-induced NFkappaB activation in a dose-dependent manner. The ZnF-A20 domain was essential for ZNF216-mediated inhibition of NFkappaB activation. The ZnF-A20 and ZnF-AN1 domains of ZNF216 could interact with each other, whereas ZNF216 could form homo-oligomers or hetero-oligomers with A20. Unlike A20, which inhibits TNF-induced apoptosis, overexpression of ZNF216 sensitized cells to TNF-induced apoptosis. Our findings suggest that ZNF216 and A20 have redundant and distinct roles in regulating NFkappaB activation and apoptosis.

Apoptosis↗
PubMed2004

Ocular oxygen consumption: estimates using vitreoperfusion in the cat.

PURPOSE: Little is known about the ocular oxygen consumption rate (QO2) in human diseases. Alterations in QO2 must occur in many conditions, such as retinal ischemia. We present a method of estimating QO2 that eventually could be used in patients during vitrectomy surgery. METHODS: We performed vitreoperfusion (i.e., perfusion of the vitreous cavity after vitrectomy) in 14 cat eyes with no ocular blood flow. The solution contained nutrients at a high partial pressure of oxygen (PO2). In eight eyes, the retinas were undisturbed (Group 1), and in six eyes, we excised the retinas (Group 2). We estimated QO2 in both groups on the basis of the temporal decline of PO2 in the vitreoperfusion solution according to a pharmacokinetic model. RESULTS: The mean and standard deviation of QO2 was 3.2 +/- 0.8 microL/min in Group 1 and 0.4+/- 0.7 microL/min in Group 2, with the difference being the retinal contribution, 88%. In Group 1, metabolism, bulk flow, and diffusion accounted for 82, 13, and 5%, respectively, of the oxygen loss from the vitreoperfusion solution. CONCLUSION: We estimated ocular oxygen consumption by means of vitreoperfusion. Eventually, the pathophysiology of human diseases may be clarified by similar measurements during vitrectomy.

Animals↗
PubMed2004

[The T cells activated by dendritic cells derived from AML cells: a study of their cytotoxic effect on autologous AML cells].

OBJECTIVE: To culture dendritic cells (DCs) from human acute myeloid leukemia (AML) cells, and to observe the cytotoxic effect of the T lymphocytes that are activated by DCs pulsed with leukemic antigen peptides (LAP) or LAP-heat shock protein 90 (HSP90) on autologous AML cells. METHODS: Mononuclear cells (MNC) were isolated from peripheral blood (PB) and bone marrow (BM) of patients with AML by density gradient centrifugation; DCs were induced from MNC of PB in a special culture system including recombinant human granulocyte-monocyte colony stimulating factor (rhGM-CSF), interleukin-4 (rhIL-4) and tumor necrosis factor-alpha (TNF-alpha) for 7-14 days. These DCs were identified by morphology and immunophenotype studies; LAP were obtained by repeatedly freezing and thawing AML cells respectively. DCs were pulsed with LAP and LAP-HSP90 compounds respectively. The cytotoxity of T lymphocytes activated by antigen pulsed DCs on autologous AML cells was measured in vitro by the lactate dehydrogenase-release assay. RESULTS: After 7-14 days' culture, (6-11) x 10(4) DCs were obtained from 1 x 10(6) MNC of PB in 3 AML cases. The cytotoxity rates of T lymphocytes, from 3 AML cases, activated by DCs pulsed with LAP and LAP-HSP90 compounds were (35.33+/-9.04)% and (62.07+/-8.29)% respectively. CONCLUSION: Effective cytotoxity of T lymphocytes to the autologous leukemia cells can be induced by DCs pulsed with LAP and LAP-HSP90 compounds respectively, but the effectiveness induced by the latter is more powerful than that induced by the former.

Acute Disease↗
PubMed2004

[Analysis of T cell subsets and CD3zeta chain expression in myelodysplastic syndrome patients].

Immune mediated suppression of hematopoiesis has been considered as one of the most important mechanisms leading to pancytopenia in myelodysplastic syndromes. This research was aimed at evaluating immune state of the MDS patients, analyzing the peripheral blood T cell subsets and CD3zeta chain expression and searching the possible reasons of hematopoietic disorders in 11 cases of MDS. Peripheral blood mononuclear cells were collected from 11 patients whose diagnosis was confirmed according to the new WHO diagnostic criteria. Flow cytometry was used for the counts of IFNgamma(+)CD4(+) cell (Th1), IL4(+)CD4(+) cell (Th2), IFNgamma(+)CD8(+) cell (Tc1), and IL4(+)CD8(+) cell (Tc2), and for the analysis of expression of CD3zeta chain in T cell subsets. The results showed that CD8(+) cells increased significantly in MDS patients; there was no significant difference between Th1/Th2, Tc1/Tc2 ratios of T cell subsets and normal control; CD3zeta chain, the functional protein in the signal transduction pathway of T cell, was over expressed in the CD8(+) cell. In conclusion, research indicates that abnormal changes of T cell subgroups exist in peripheral blood of MDS patients. Enhancement of CD8(+) cells and over-expression of CD3zeta chain are important features, which suggest that CD8(+) cells play the most critical role in the pathologic process as compared with other T cell subsets. The over active immunity mediated by T cell subset may be one of the major mechanisms resulting in cytopenia in MDS.

Aged↗
PubMed2003

Identification of a novel serine/threonine kinase that inhibits TNF-induced NF-kappaB activation and p53-induced transcription.

SINK is a p65-interacting protein that inhibits PKAc-induced phosphorylation of p65 and NF-kappaB transcriptional competence. We identified a SINK-homologous serine/threonine kinase SHIK. SHIK is ubiquitously expressed and is localized in the cytoplasm. Overexpression of SHIK inhibits TNF-triggered NF-kappaB activation in reporter gene assays. Overexpression of SHIK also inhibits p53-mediated transcription in reporter gene assays, while a point mutant (D197-->I) of SHIK potentiates p53-mediated transcription. Our findings suggest that SHIK is a negative regulator of NF-kappaB- and p53-mediated gene transcription.

Amino Acid Sequence↗
PubMed2003

Sodium chloride modified silica nanoparticles as a non-viral vector with a high efficiency of DNA transfer into cells.

Development of reliable vectors is a major challenge in gene therapy. Previous gene transfer methods using non-viral vectors, such as liposomes or nanoparticles, have resulted in relatively low levels (35 to approximately 50%) of gene expression. We have developed a silicon nanoparticle (SNAP) system, a novel non-viral vector, for DNA transfer into cells. SNAP was synthesized chemically and modified with sodium chloride or sodium iodide. Electronmicroscopy of SNAP and fluorescence microscopy of fluorescence-labeled SNAP revealed that they were generated uniformly, had diameters of 10-100 nm, and showed a better efficiency (about 70%) of DNA transfection into cells as well as protection of DNA against degradation. The microscopy also demonstrated the adhesion of SNAP with HT1080 cell surface and entry of SNAP into the cells without cytotoxicity. Intravenous and/or intra-abdominal administration of the SNAP to mice revealed the accumulation of SNAP in the cells of the brain, liver, spleen, lung, kidney, intestine, prostate and the testis without any pathological cell changes or mortality, suggesting that they passed through the blood-brain, blood-prostate, and blood-testis barriers. These findings indicate that the SNAP generated has good biological characteristics as a potential promising vector for gene transfer, gene therapy and drug delivery.

Animals↗
PubMed2003

[The variation of Caspase3 activity in tanshinone induced NB4 cells apoptosis].

OBJECTIVE: To study the variation and role of Caspase3 activity in the process of Tanshinone (Tan II A) induced NB4 cells apoptosis. METHODS: NB4 cell apoptosis induced by Tan II A was demonstrated by cell morphology, DNA content analysis and DNA fragmentation assay. Caspase3 activity was determined by spectrofluorometry, and its inhibitory assay was performed using N-acetyl-Asp-Glu-Val-Asp-aldehyde(AC-DEVD-CHO). RESULTS: Tan II A could induce NB4 cell apoptosis accompanied with increase of caspase3 activity. The induction of NB4 cell apoptosis by use of Tan II A could be partially inhibited by AC-DEVD-CHO. CONCLUSION: The induction of NB4 cell apoptosis by Tan II A could be fulfilled by activating Caspase3.

Abietanes↗
PubMed2003

[Quantitative analysis of mixed hematopoietic chimersim based short tandem repeats loci after nonmyeloablative stem cell transplantation].

OBJECTIVE: To establish a method for quantitative analysis of mixed hematopoietic chimerism (MC) based on STR loci. METHODS: Using STR technique combined with PCR, we analyzed the peripheral blood samples collected from 3 nonmyeloablative stem cell transplantation recipients every 15 days after transplantation. RESULTS: The quantitative results coincided with the qualitative results of DNA electrophoresis and with the clinical outcomes. When the result of electrophoresis showed only donor's allele type we could still find out the recipient's specific allele. CONCLUSION: The quantitative analysis using STR-PCR can detect more subtle changes in the evidence of engraftment. It is a more efficient method for detect the hematopoietic chimerism post transplantation.

Chimera↗
PubMed2003

[The research update on cellular immune abnormality in myelodysplastic syndrome--review].

Myelodysplastic syndrome is a group of diseases characterized by abnormal clonal proliferation of hematopoietic cells and pancytopenia with dysplasia. The pathogenesis of MDS includes factors of chromosome aberrations, gene mutations, immune abnormalities, environmental changes, and so on. Now it is commonly accepted that MDS is a multistep process disorder involving more etiologic alterations. Recently more and more investigations indicate that the abnormality of cellular immunity is one of important reasons related to MDS. Some proofs about the abnormal activation of T-cell and the abnormal expressions of cytokines in different stages of immune response in MDS have been documented, meanwhile, numerous clinical studies on immune therapy in MDS provide a great number of evidences to disclose its immune abnormalities.

Cytokines↗