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Ling Zhang

Publications and source records attributed to Ling Zhang.

175 records · Page 10Linked to original sources
PubMed2002

IL-7 inhibits fibroblast TGF-beta production and signaling in pulmonary fibrosis.

Based on studies by our group and others, we hypothesized that IL-7 may possess antifibrotic activities in an IFN-gamma-dependent and independent manner. Here, we have evaluated the antifibrotic therapeutic potential of IL-7 in both in vitro and in vivo pulmonary fibrosis models. IL-7 inhibited both TGF-beta production and signaling in fibroblasts and required an intact JAK1/STAT1 signal transduction pathway. IL-7-mediated inhibition of TGF-beta signaling was found to be associated with an increase in Smad7, a major inhibitory regulator in the SMAD family. In the presence of IL-7, Smad7 dominant negative fibroblasts restored TGF-beta-induced collagen synthesis, indicating that an IL-7-mediated increase in Smad7 suppressed TGF-beta signaling. Consistent with these in vitro findings, recombinant IL-7 decreased bleomycin-induced pulmonary fibrosis in vivo, independent of IFN-gamma. The antifibrotic activities of IL-7 merit further basic and clinical investigation for the treatment of pulmonary fibrosis.

Animals↗
PubMed2002

[Nucleic acid quantifying assay of hepatitis B virus].

OBJECTIVE: To explore the relation between the nucleic acid content of hepatitis B virus and hepatitis B virus markers, liver function and its pathological state. METHODS: Thirty-nine patients suffering from chronic hepatitis B with positive HBsAg were performed liver puncture for histopathological examination. Fluorescence ration PCR analysis was used for HBV DNA quantifying assessment. Hepatitis B virus markers were detected by ELISA. RESULTS: Serum HBV DNA content was related to hepatitis B virus markers. There was no correlation between HBV DNA level and the Scheuer grade in patients with positive HBsAg, and no obvious correlation between serum glutamic pyruvic transaminase level and HBV DNA content. CONCLUSIONS: There is a significant correlation between HBeAg and HBV DNA, but not between liver inflammation stage and serum HBV DNA content.

Adolescent↗
PubMed2002

[Plerosis of cDNA array of normal human nasopharyngeal tissue and nasopharyngeal carcinoma].

OBJECTIVE: To compare gene expression gene profile of nasopharyngeal carcinoma (NPC) tissue with that of normal nasopharyngeal tissues by cDNA array and to discuss possible functions of DNA repair-related genes in NPC tissue. METHODS: After hybridization of atlas human cancer cDNA expression array 7742 - 1, atlas hybridization results were analyzed by Atlas Image 1.01 a software package. Using RT-PCR was used to confirm the results. RESULTS: Of 63 differentially expressed genes in quadrangle C including DNA damage response, repair & recombination-related genes, 6 DNA repair-related genes were up-regulated, 12 were down-regulated. CONCLUSION: DNA repair-related genes may be involved in patho-physiological process of nasopharyngeal carcinoma.

DNA Repair↗
PubMed2002

[The effect of TNP-470 on the proliferation and apoptosis of lung adenocarcinoma cells].

OBJECTIVE: To investigate the effect of TNP-470 on the proliferation and apoptosis of lung adenocarcinoma cells and to explore the mechanism of the effect. METHODS: The TNP-470 with different concentrations was added to cultured lung adenocarcinoma cell strain AGZY-82A and the expressions of proliferating cell nuclear antigen (PCNA), p53, bcl-2, vascular endothelial growth factor (VEGF) and VEGF receptor Flk-1 of the tumor cells were assessed by immunohistochemical methods. RESULTS: The experimental data showed that TNP-470 inhibit the expressions of VEGF and Flk-1 by tumor cells with dose-dependence. In the group of cells without TNP-470 (control group) the expression could rates of VEGF and Flk-1 were 70.42% and 50%, respectively; while in the group of cells with 10(7) microgram/L TNP-470, the expression rates of VEGF and Flk-1 decreased to 13.2% and 7.2%, respectively. Under the lnfluence of 10(4) microgram/L TNP-470, the expression rates of VEGF, Flk-1 by the tumor cells decreased gradually with prolonging of the action time. After 6 hours of action, the expression rate of VEGF decreased to 14.4% and after 12 hours, the expression rate of Flk-1 decreased to 6.2%. In the control group the proliferation rate of PCNA-marked cells was (87.03 +/- 0.75)% and the positive expression rate of p53-marked cells was (3.67 +/- 0.39)%, while in the 10(7) microgram/L TNP-470 group the proliferation rate and positive rate of p53-marked cells were 0 and (63.28 +/- 0.84)%, respectively. No expression of bcl-2 in both control and low concentration TNP-470 group. Its expression increased gradually as the concentration induced. In the 10(4) microgram/L TNP-470 group the expression of PCNA by tumor cells decreased. But the expression of p53, bcl-2 increased gradually with prolonging of the action time. CONCLUSION: TNP-470 could inhibit the proliferation and promote the apoptosis of lung adenocarcinoma cells through reduction of the VEGF autocrine and down-regulation of the VEGF receptor.

Adenocarcinoma↗
PubMed2002

[Physiological characteristics of resistance of different plum varieties to artificial adverse environments].

The relative electric conductivity, soluble sugar content in leaf, and POD activity of 17 plum varieties, which belong to six species and one genera, were measured under artificial adverse environments. The results showed that there were extreme significant negative correlation (alpha = 0.01) between soluble sugar content and membrane freezing damage, and significant negative correlation (alpha = 0.05) between POD activity in bark and leaf cell heat damage. According to Fuzzy synthetic evaluation, the comprehensive resistances of different plum varieties to adverse circumstances were discussed in this paper.

Carbohydrate Metabolism↗
PubMed2002

Cloning and high level nonfusion expression of recombinant human basic fibroblast growth factor in Escherichia coli.

AIM: To obtain high-level expression of nonfusion recombinant human basic fibroblast growth factor (rhbFGF). METHODS: hbFGF cDNA was prepared from the total RNA of embryonic brain tissue. As a template, the obtained gene was used to clone nonfusion rhbFGF. New primers were employed to alter the translation initiation region (TIR) and reduce the G+C content through nucleotide change. Using pET-3C as vector, the cloned rhbFGF was expressed in BL21 (DE3). RESULTS: rhbFGF was expressed in E coli up to 30 % of the total cellular protein. Cation exchange and heparin affinity chromatography were employed to purify the target protein from the supernatant of bacteria lysate. The bioactivity of the purified rhbFGF was identical with the standard bFGF. CONCLUSION: Modification of TIR is an effective means to increase nonfusion expression rate of recombinant proteins, such as rhbFGF, in E coli.

Base Sequence↗
PubMed2002

The effect of predictable and unpredictable motor tasks on postural control after traumatic brain injury.

This study examined the effects of environmental predictability on postural control during functional reaching while seated in healthy individuals and patients with traumatic brain injury (TBI). The postural perturbation used required reaching to the left versus reaching to the right, while seated, under predictable versus unpredictable conditions. Indexes of postural control--trajectory stability and response reach times--were measured using an electromechanical system in ten patients with TBI and ten healthy subjects. In the TBI group, greater trajectory stability and shorter response reach time were recorded under unpredictable conditions when reaching to both the right and left (d-index 0.57-2.3). In the control group, greater trajectory stability and shorter response time were recorded under predictable and unpredictable environments compared with the TBI group (d-index 0.46-0.95). This study refutes the hierarchical, predictable-to-unpredictable-environment model of postural control evaluation and treatment. The relationship between information processing demands and postural skill appears more complex than a simple linear association. Predictable and unpredictable conditions may be used concurrently, not sequentially, in TBI rehabilitation.

Adult↗
PubMed2002

[Construction of transgenic mice carrying enhanced green fluorescent protein gene by seminiferous tubule microinjection].

OBJECTIVE: To study the feasibility of establishing transgenic mice carrying enhanced green flourescent protein (EGFP) gene by means of seminiferous tubule microinjection. METHODS: The vector expressing enhanced green fluorescent protein under the control of human cytomegalovirus immediate-early promoter (pCMV-EGFP) was selected and mixed with liposome in vitro. Microinjection at different doses of the liposome-entrapped plasmid DNA into the seminiferous tubules of male mice at different ages was performed to establish transgenic mice, which were made to mate with female mice at least 40 d after the microinjection. Genomic DNA was extracted from the offspring of the founder mice for PCR and Southern blotting analysis, and the frozen sections of different tissues from 2 of the founders mice were prepared for fluorescence microscopic observation. RESULTS: Among the 41 mice receiving the microinjection, 32 survived and retained their mating ability and fertility, and among their 382 offspring 133 were positive for EGFP DNA as demonstrated by PCR, 15 of which were confirmed by Southern blotting analysis. The age of the mice or the doses of microinjection they received was not shown to impact the integration of EGFP gene, and fluorescence microscopy failed to detect significant EGFP expression in the tissues of the founder mice (P>0.05) in comparison with normal mice. CONCLUSION: Seminiferous tubule microinjection is simple and practicable to implement gene transfer in mice.

Animals↗
PubMed2002

[Molecular mechanisms of tumorgenesis and metastasis in nasopharyngeal carcinoma cell sublines].

BACKGROUND & OBJECTIVE: The authors have selected three different biological character sublines, including 5-8F (the highest tumorigenic and metastatic ability), 6-10B(the lowest tumorigenicity and lack of metastatic ability), and 13-9B(lack of tumorigenic ability), from colony lines of nasopharyngeal carcinoma cell line(SUNE-1). The aim of this study was to determine the molecular mechanisms of different biological character of SUNE-1 and its three sublines from two aspects of genetic and virology. METHOD: 1. Amplifying Epstein-Barr virus(EBV) BamHI W fragment by PCR. 2. Determining the expression of latent membrane protein1(LMP1) of EBV in the sublines using in situ hybrization. 3. Molecular cytogenetic analysis of the cell line and sublines by comparative genomic hybridization (CGH). RESULTS: 1. There was EBV BamHI W fragment in SUNE-1 and its three sublines. 2. Expression of LMP1 was observed in the SUNE-1 and its three sublines, and their expression intensity was identical. 3. There were DNA copy number gains on chromosomes 1, 2p, 3, 4, 5p, 6, 7, 9, 10q, 11, 12q, 13q, and 18q as well as loss on 22q in the SUNE-1 cell line; DNA copy number gains on chromosomes 3p, 7q, 8q, 9q, and 10q were observed in 5-8F subline; DNA copy number loss on few chromosomes, but no DNA copy number gain was observed in the 6-10B and 13-9B sublines. CONCLUSION: There were expression of EBV and different genetic changes in the SUNE-1 and its three sublines. It is suggesting that the different biological character tumorgenesis and metastasis of nasopharyngeal carcinoma cell sublines may be due to genetic changes; and EBV infection may play an important role in keeping the malignant phenotypic of nasopharyngeal carcinoma.

DNA, Neoplasm↗
PubMed2002

[Distribution of neuropeptide Y-like immunoreactive fiber in rat temporomandibular joint].

OBJECTIVE: This investigation aimed at explore the total distribution of neuropeptide Y-like immunoreactive (NPY-LI) fibers and their changes post-trauma in rat temporomandibular joints (TMJs). METHODS: Six groups of rats were killed individually before trauma, 1, 3, 7, 14 and 28 days after trauma. TMJs were extracted totally, and the avidin-biotin-peroxidase complex method and image analysis were employed to detect NPY-LI fibers in frozen sections of TMJs. RESULTS: NPY-LI fibers were distributed extensively in TMJs, except the central disc band and bone, and they were mainly located around blood vessels, especially arteries. The densities of fibers in the six groups were 160.4 +/- 27.5, 95.8 +/- 16.4, 88.6 +/- 14.5, 114.3 +/- 17.0, 135.0 +/- 20.7, 158.6 +/- 19.5 (unit:mm2). CONCLUSION: NPY-LI nerve fibers are distributed extensively in the periphery of blood vessels of TMJs and densities changed dynamically when TMJs were impacted. NPY may play an important role in pathologic change of TMJ by regulating local blood circulation.

Animals↗
PubMed1999

Gene Expression Profiles of Human Fetal Nasopharyngeal Tissue.

To study differentially expressed genes in nasopharynx tissues of embryo during development, and to observe the gene changes, total RNAs were respectively extracted from the nasopharynx tissue which came from fetuses of 5, 6, 7, and 8 month, Probes were yielded by reverse transcription and were used to hybridize with the Atlas(TM) human cDNA expression arrays. The results showed that the genes expression profile were distinctly different and different expression levels were found in the same gene during development. Results indicated that gene expression pattern had a character of time-dependence, such as early growth response protein 1 and the cDNA expression array provided a powerful method for studying gene expression profile in a large range of genes.

Journal Article↗
PubMedDate not supplied

Polypeptide multilayer films.

Research on polypeptide multilayer films, coatings, and microcapsules is located at the intersection of several disciplines: synthetic polymer chemistry and physics, biomaterials science, and nanoscale engineering. The past few years have witnessed considerable growth in each of these areas. Unexplored territory has been found at the borders, and new possibilities for technology development are taking form from technological advances in polypeptide production, sequencing of the human genome, and the nature of peptides themselves. Most envisioned applications of polypeptide multilayers have a biomedical bent. Prospects seem no less positive, however, in fields ranging from food technology to environmental science. This review of the present state of polypeptide multilayer film research covers key points of polypeptides as materials, means of polymer production and film preparation, film characterization methods, focal points of current research in basic science, and the outlook for a few specific applications. In addition, it discusses how the study of polypeptide multilayer films could help to clarify the physical basis of assembly and stability of polyelectrolyte multilayers, and mention is made of similarities to protein folding studies.

Absorbable Implants↗