PubMed Health⌕ Search

Biomedical subjects

Ling Zhang

Publications and source records attributed to Ling Zhang.

At least 109 records · Page 6Linked to original sources
PubMed2005

Extensive aortic thromboembolism due to acquired hypercoagulable state: an autopsy case report.

Aortic thrombosis rarely occurs without severe atherosclerosis, aneurysm, or cardiosurgical or traumatic state. Arterial thrombosis is commonly related to an inherited and/or acquired hypercoagulable state. A 50-year-old woman presented with diffuse abdominal pain. One day after her admission, she experienced bloody stools. Computed tomography showed multiple extensive thromboses in the aorta and superior mesentery arteries. She underwent a partial jejunoileostomy and colectomy for extensive bowel infarction. Following surgery, her condition deteriorated and she died on the fourth hospital day. At autopsy, gross examination showed 2 large thrombi (7 and 8 cm in length) in the proximal and descending (thoracic) aorta, with mild atherosclerosis. A mesenteric artery thromboembolus with extensive bowel infarction was present. Postmortem laboratory studies revealed an elevated anticardiolipin immunoglobulin G antibody level. The thrombotic state in this patient was considered multifactorial secondary to acquired risk factors, including obesity, mild aortic atherosclerosis with coronary artery disease, and presence of a high titer anticardiolipin antibody.

Aorta, Thoracic↗
PubMed2005

[A multi-center clinical study of N-acetylcysteine on chronic hepatitis B].

OBJECTIVES: To evaluate the effectiveness and safety of N-acetylcysteine (NAC) in treating chronic hepatitis B patients. METHODS: 144 patients with chronic hepatitis B (total bilirubin, TBil>170 mmol/L) from several centers were chosen for a randomized and double blind clinical trial. The patients were divided into a NAC group and a placebo group and all of them were treated with an injection containing the same standardized therapeutic drugs. A daily dose of 8 microgram NAC was added to the injection of the NAC group. The trial lasted 45 days. Hepatic function and other biochemistry parameters were checked at the experimental day 0 and days 15, 30, 45. RESULTS: Each group consisted of 72 patients of similar demology and disease characteristics. During the trial, 28 cases of the 144 patients dropped out. In the NAC group, at day 0 and day 30, the TBil were 401.7 vs. 149.2 and 160.1+/-160.6. In the placebo group, the TBil on the corresponding days were 384.1+/-134.0 and 216.3+/-199.9. Its decrease in the NAC group was 62% and 42% in the placebo group. At day 0 and day 45 of treatment, the effective PTa increase rate was 72% in the NAC group and 54% in the placebo group. The total effective rate (TBil + PTa) was 90% in the NAC group and 69% in the placebo group. The parameters of the two groups showed a remarkable difference. The rate of side effects was 14% in the NAC and 5% in the placebo groups. CONCLUSION: NAC can decrease the level of serum TBil, increase the PTa and reduce the time of hospitalization. NAC showed no serious adverse effects during the period of our treatment. We find that NCA is effective and secure in treating chronic hepatitis B patients.

Acetylcysteine↗
PubMed2005

[Expression of Interleukin-8 in KB cells infected with Candida albicans].

PURPOSE: To investigate the change of interleukin-8 (IL-8) in oral epithelial cells (KB cells) infected with Candida albicans. METHODS: Two-site ELISA and RT-PCR were applied to determine the levels of IL-8 protein or mRNA expression in the KB cells induced by hyphae, yeast, killed Candida albicans and medium respectively. The unpaired Student's t test was used to analyse the data. RESULTS: Candida albicans induced the KB cells secrete more IL-8. The hyphae, yeast, killed Candida albicans and control group marks of RT-PCR were 180.23, 186.36, 143.41 and 85.57 respectively, calculated using a two-tailed test, P<0.05, was considered to be significant, but the medium group (mark 80.87) had no significant change. The tendency of the IL-8 protein secreted by KB cells increased with the time but reduced when Candida albicans was more. CONCLUSIONS: Candida albicans is responsible for the production of IL-8 secreted by oral epithelial cells which can be expected to play an important role in the infection and defection with the local oral mucosa.

Candida albicans↗
PubMed2005

[Influence of process methods on contents of chemical component Radix Polygoni Multiflori].

Different methods of processing Radix Polygoni Multiflori and the change of chemical components including emodin, physcion, 2,3,5,4'-stilbene glucoside, and tannin were investigated. The dried roots of polygoni were processed in different ways, such as, steamed with black bean sauce, steamed with water, stewed with black bean sauce, and stewed with black bean sauce at high pressure, for h and 36 h, respectively. The process stewing with black bean sauce was also investigated for 12, 24, 36 h, and 48 h, respectively. The results indicated that 2,3,5,4'-stilbene glucoside and total free anthraquinones varied in different processes. In the process of black bean sauce stewing, the content of 2,3,5,4'-stilbene glucoside decreased with processing time, reached 17% of original at 48 h. The content of tannin and combined and free anthraquinones also decreased with processing time. It was concluded, therefore, that the processing of Radix Polygoni Multiflori should be standardized to avoid significant variation of chemical contents.

Emodin↗
PubMed2005

[Effects of early treatment with metoprolol on myocardial inflammatory cytokine expression and heart function in rats with acute myocardial infarction].

OBJECTIVE: The aim of study was to explore the effects of early beta-adrenergic blockade-metoprolol treatment on myocardial inflammatory cytokine expression and heart function in rats after acute myocardial infarction (AMI). METHODS: The therapeutic effects of metoprolol on myocardial inflammation and heart function up to 4 weeks (according to the protocol of CCS-2) were studied by the rat model of AMI. Myocardial inflammation was examined by taking account of the number of lymphocytes infiltrated in the myocardium and analyzing the myocardial cytokine production including the pro-inflammatory cytokines: interleukin (IL)-1beta, 6 and tumor necrosis factor (TNF)-alpha and the anti-inflammatory cytokine: IL-10. Echocardiography was used to evaluate heart function. RESULTS: The levels of TNF-alpha, IL-1beta, IL-6 and IL-10 in AMI group were markedly elevated compared to sham rats (P < 0.01) and the cytokines principally excreted by cardiac myocytes. After 4 weeks therapy, metoprolol reduced the production of TNF-alpha and IL-1beta and increased IL-10 levels (P < 0.05) in cardiac myocytes, but had no effect on the number of lymphocytes infiltrated in myocardium. Echocardiography showed that metoprolol markedly improved left heart function (P < 0.05). CONCLUSION: Early metoprolol treatment can improve heart function and myocardial inflammatory cytokine expression after AMI. One immunopharmacologic mechanism underlying the beneficial effects of beta-adrenergic blockade may involve the attenuation of pro-inflammatory cytokines and the increase of anti-inflammatory cytokine levels in cardiac myocytes.

Adrenergic beta-Antagonists↗
PubMed2005

[Fusion expression, purification and bioassay of IFN-gamma inducible protein-10 and thioredoxin gene in E. coli].

Interferon gamma-inducible protein 10, a member of the family of CXC chemokines, is secreted by interferon gamma-stimulated, monocytes, endothelial cells and keratinocytes. Interferon gamma-inducible protein 10 plays an important role in recruiting activated T cells into sites of tissue inflammation. In this experiment, PCR products of Interferon gamma-inducible protein 10 were cloned into prokaryote expression vector pET 32(a) to generate recombinant pET-IP10 with S-Tag at the N-terminus, and expressed successfully in E. coli BL21 (DE3). The total expressed products amounted to 25.3% in all bacterion proteins. pET-IP10 mainly formed inclusion body in E. coli. Soluble recombinant protein accounted for 20% among IP-10 fusion protein. The soluble recombinant proteins were purified by using S-Tag affinity chromatography effectively with purity of over 90%. The chemotaxis biological activity of purified Interferon gamma-inducible protein 10 could specifically exhibit the directional migration of stimulated T cells at concentration of 100 ng/ml. The results indicated that the strategy we used in this experiment was effective for recombinant Interferon gamma-inducible protein 10 production with biological activity.

Chemokine CXCL10↗
PubMed2005

[Effect of full-length cyclin B1 antisense cDNA on chemosensitivity of lewis lung carcinoma cells to gemicitabine in vitro and in vivo].

OBJECTIVE: To evaluate the effect of full-length cyclin B1 antisense cDNA (AS-CLB1) on chemosensitivity of Lewis lung carcinoma cells (LL/2) to gemicitabine (GEM) in vitro and in vivo and hence provide a therapeutic regiment for treating non-small cell lung (NSCL) cancer using AS-CLB1 combined with GEM. METHODS: Cell cycle phase distribution and apoptosis of LL/2 parent cells, LL/2/vect and LL/2/AS-CLB1 transfectants (LP, LV and LA cells) were determined by flow cytometry. In addition, the three kinds of cells were treated with GEM (20 nmol/L-20 micromol/L) in vitro for 1 h and 24 h respectively, and then cytotoxicity of GEM was measured by MTT assay. After inoculation with the three kinds of cells respectively, the C57BL/6 mice were treated with GEM [25 - 125 mg/(kg x day)] once every three days for four times when tumors developed; tumorigenicity and survival were observed and cell apoptosis in tumor tissues was determined by flow cytometry. RESULTS: LA cells displayed apparent apoptosis and G1 arrest compared with LP and LV cells (controls). Additionally, cytotoxicity of GEM to LA cells was more obvious than that to controls. Moreover, tumorigenicity was inhibited, cell apoptosis in tumor tissues was induced, and survival was evidently increased in LA cells group. CONCLUSION: AS-CLB1 slightly increased the sensitivity of LL/2 cells to GEM in vitro and in vivo. The function of AS-CLB1 may be associated with its ability to enhance the anti-tumor activity of GEM by inducing cell apoptosis and G1 arrest.

Animals↗
PubMed2005

[cDNA microarray and cluster analysis to identify the significance of immune genes associated with benzene poisoning].

OBJECTIVE: To delineate the immune regulatory pathway of benzene poisoning by using gene expression profile analysis. METHODS: Peripheral white blood cell gene expression profile of 7 benzene poisoning patients, including one aplastic anemia, was determined by microarray. Seven chips from normal workers were served as controls. Cluster analysis of gene expression profile was performed. Differentially expressed immune genes associated with benzene poisoning were determined. RESULTS: Among the 2 779 target genes, 38 genes differentially expressed were identified, including 10 up-regulated genes such as CD59, TRA@, MCP etc, and 14 down-regulated genes such as HLA-DMB, HLA-DQA1, HLA-DPB1, ITGB2, PFC etc. Cluster analysis showed that the expression profiles of 38 genes were associated with benzene poisoning. CONCLUSION: Differentially expressed immune genes may play an important role in the pathogenesis of benzene poisoning.

Benzene↗
PubMed2005

[The expression levels of endothelin-1 and nuclear factor-kappaB in the lung tissue of acute pulmonary embolism and the effects of thrombolysis and dexamethasone].

OBJECTIVE: To study the expression levels of endothelin-1(ET-1) and nuclear factor-kappaB (NF-kappaB) in lung vascular endothelium, bronchial and alveolar epithelia in acute pulmonary thromboembolism (APTE), and to explore the effects of thrombolytic (urokinase, UK) or ant-inflammatory therapy (dexamethasone, Dex) on their expressions. METHODS: Forty rabbits were randomly divided into a control (C) group, a pulmonary thromboembolism (PTE) model group, an UK therapy group, a Dex therapy group, and an UK + Dex therapy group, with 8 rabbits each. The PTE model was established by intravenous injection of autologous blood clots. The pathological changes of the lung were examined with light microscope. By using immunohistochemistry, the expression levels of ET-1 and NF-kappaB P65 in lung vascular endothelium, bronchial and alveolar epithelia were examined. RESULTS: Histopathological study showed that lung injury was evident in the PTE, UK and Dex groups, but was mild in the UK + Dex group. In the PTE group, the expression levels of ET-1 in lung vascular endothelium, bronchial and alveolar epithelia were 0.331 +/- 0.036, 0.229 +/- 0.014 and 0.191 +/- 0.046, respectively, while the expression levels of NF-kappaB P65 were 0.245 +/- 0.036, 0.190 +/- 0.040 and 0.204 +/- 0.054, respectively. Their levels were significantly higher as compared to those of the control group and the UK + Dex group (all P < 0. 01). In the UK group, the ET-1 expression in lung vascular endothelium, bronchial and alveolar epithelia were 0.204 +/- 0.020, 0.163 +/- 0.017 and 0.137 +/- 0.013 respectively, significantly lower as compared to the PTE group (all P < 0. 05). In the Dex group, the NF-kappaB P65 expression was 0.175 +/- 0.024, 0.104 +/- 0.022 and 0.144 +/- 0.022 respectively, the difference being significant as compared with the PTE group (all P < 0. 05). In the UK + Dex group, the ET-1 expression was 0.186 +/- 0.033, 0.107 +/- 0.012 and 0.098 +/- 0.026 respectively, significantly different from the PTE group (all P < 0.05); the NF-kappaB P65 expression was 0.109 +/- 0.018, 0.062 +/- 0.023 and 0.093 +/- 0.019 respectively, significantly lower as compared with the PTE and the UK groups (all P < 0. 01). CONCLUSIONS: After APTE, thrombolytic and anti-inflammatory treatment could decrease acute lung injury induced by ET-1 and NF-kappaB activation. Thus, anti-inflammatory therapy and the use of ET-1 inhibitor or receptor antagonist should be considered in APTE.

Animals↗
PubMed2005

The construction, characterization and transfection of liposome- polycation-CDKN1B plasmid complexes.

OBJECTIVE: To develop an efficient non-viral gene delivery system in order to transfer CDKN1B gene efficiently into lung and liver carcinoma cells. METHODS: A recombinant plasmid composed of CDKN1B sequence and EYFP as reporter gene was constructed and identified. The recombinant DNA was then formulated the lipids-polycation-DNA complexes(LPDs) with protamine sulfate. Several kinds of lung and liver carcinoma cells were transfected by means of LPDs. The physicochemical properties of LPDs were investigated using PCS method and TEM, respectively. The expression of EYFP in A549 cells was observed under fluorescent microscope and evaluated by flow cytometry analysis. Finally, the production of CDKN1B protein in transfected LLC, Chang and 7721 cells was identified by Western blot analysis. RESULTS: The average diameter of the LPDs were 167 nm with the polydispersity index of 0.35. The average zeta potential of LPDs was +32.6 mV. LPDs look like a sunken sphere. The fluoresent microscope picture clearly indicated the expression of EYFP in A549 cells. The flow cytometry result showed that the transfection efficiency of LPDs in A549 cells was comparable with that of LipofectAMINE, the positive control. Western blot analysis confirmed the production of CDKN1B protein in LLC, Chang and 7721 cells transfected with LPDs, while no CDKN1B protein was detected in cells transfected with naked DNA. CONCLUSION: The construction of the recombinant plasmid is successful. LPDs can deliver the recombinant plasmid to lung carcinoma cells and liver carcinoma cells with high efficiency. Therefore, this kind of gene delivery system has the potential uses for the treatment of lung and liver cancer.

Blotting, Western↗
PubMed2005

[Expression of human phosphodiesterase 3A gene using baculovirus expression system in insect cell].

AIM: To investigate the expression of recombinant human phosphodiesterase 3A (HPDE3A) using baculovirus expression system in Tn cell line. METHODS: The HPDE3A cDNA was recombined with baculovirus, and then the recombinant was transfected into Tn cell line. The expression of HPDE3A in Tn cell line was detected and identified by the RT-PCR, SDS-PAGE and Western blotting. RESULTS: The recombinant HPDE3A protein was stably expressed in Tn cell line and detected by the distinct morphological changes of Tn cell, RT-PCR, SDS-PAGE and Western blotting using polyclonal antibody. The M(w) of the recombinant protein was about 120 kD. CONCLUSION: Recombinant HPDE3A can be expressed in Tn cell line using the baculovirus expression system, and thus provided the basic material for studying its bioactivity and application in screening for HPDE3A inhibitor.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2005

A simplified algorithm for the laboratory detection of lupus anticoagulants: utilization of two automated integrated tests.

Diagnosis of antiphospholipid antibody syndrome includes laboratory testing for lupus anticoagulants (LAs). Guidelines for testing have been published, but approaches vary, often incorporating multiple tests. We evaluated the performance of the activated partial thromboplastin time using 2 reagents, a dilute Russell viper venom time, and a hexagonal phospholipid assay for detecting LAs in 105 adults. Of the patients, 26 were taking anticoagulants at the time of testing. Based on findings, an algorithm was derived for optimal detection of LAs using 2 easily performed, automated, integrated test systems. Of 105 patient samples, 30 (28.6%) were positive for LAs, using the algorithm interpretive criteria. Of these 30 positive results, 10 were detected in the 26 patients taking anticoagulants. Analysis by chi2 showed no difference in performance of the integrated tests between samples from patients taking and not taking anticoagulants. The algorithm is offered as a means for standardization of laboratory testing for LAs.

Algorithms↗
PubMed2005

[Establishment of three-dimensional culture models related to different stages of nasopharyngeal carcinogenesis].

BACKGROUND & OBJECTIVE: Since three-dimensional culture simulates in vivo microenvironment better than planar culture, the biological character of cells in three-dimensional culture model are more similar with that of living tissues. This study was to establish three-dimensional culture models that represent different stages of nasopharyngeal caicinogenesis, and provide information to elucidate the related molecular events. METHODS: Non-tumor nasopharyngeal biopsy specimens were used to culture for normal nasopharyngeal epithelial cells. Early and late passages of normal nasopharyngeal epithelial cell line NPNE2 from nasopharyngeal biopsy specimens, immortalized nasopharyngeal epithelial cell line NP69SV40T, nasopharyngeal carcinoma (NPC) cell line SUNE-1 and its high metastatic subclone 5-8F were cultured in Matrigel to establish three-dimensional models. RESULTS: The cells grew out of non-tumor nasopharyngeal biopsy specimens displayed the morphologic characteristics as epithelia, and could proliferate in vitro for 8-10 passages before senescence. Immunocytochemical staining of cytokeratin revealed that the cells were of epithelial origin. All of the cells, except late passages of NPNE2 cells, could proliferate in the three-dimensional culture system. NPNE2 and NP69SV40T cells mainly developed reticular structures in morphology, and formed few clones with clear and smooth edges as well as tight intercellular junctions. SUNE-1 and 5-8F cells formed clones with irregular morphology, unclear edge, and loose intercellular junctions. In addition, the clones formed by 5-8F cells also developed a lot of pseudopodia, but developed no reticular structure. Late passages of NPNE2 cells formed no clone and reticular structure in the three-dimensional culture. CONCLUSIONS: Normal nasopharyngeal epithelial cells can be successfully cultured in vitro from naspharyngeal biopsy specimens. The three-dimensional culture models, established with normal nasopharyngeal epithelial cells, immortalized nasopharyngeal epithelial cells, and NPC cells, may represent the different stages of nasopharyngeal carcinogenesis.

Cell Culture Techniques↗
PubMed2004

Comparative transcriptome analysis of Yersinia pestis in response to hyperosmotic and high-salinity stress.

DNA microarray was used as a tool to investigate genome-wide transcriptional responses of Yersinia pestis to hyperosmotic and high-salinity stress. Hyperosmotic stress specifically upregulated genes responsible for ABC-type transport and the cytoplasmic accumulation of certain polysaccharides, while high-salinity stress induced the transcription of genes encoding partition proteins and several global transcriptional regulators. Genes whose transcription was enhanced by both kinds of stress comprised those encoding osmoprotectant transport systems and a set of virulence determinants. The number of genes downregulated by the two kinds of stress was much lower than that of upregulated genes, suggesting that neither kind of stress severely depresses cellular processes in general. Many differentially regulated genes still exist whose functions remain unknown. Y. pestis recognized high-salinity and hyperosmotic stress as different kinds of environmental stimuli, and different mechanisms enabled acclimation to these two kinds of stress, although Y. pestis still executed common mechanisms to accommodate both types of stress.

Gene Expression Regulation, Bacterial↗
PubMed2004

Effects of thiol antioxidant on reduced nicotinamide adenine dinucleotide phosphate oxidase in hypertensive Dahl salt-sensitive rats.

Recent studies implicate of reactive oxygen species (ROS) in hypertension; however, whether reactive oxygen species promote hypertensive derangements is not fully clear. We thus investigated the effects of an antioxidant, N-acetyl-L-cysteine, on hypertensive Dahl salt-sensitive rats. High-salt intake for 4 weeks markedly elevated systolic arterial pressure, urinary excretion of protein, 8-isoprostane, and H(2)O(2), and the enzyme activity of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase along with the elevated expression of its subunits gp91phox and p47phox at the levels of mRNA and protein. Supplement with N-acetyl-L-cysteine reduced the increase in systolic arterial pressure and counteracted the elevation of urinary excretion of protein, 8-isoprostane, and H(2)O(2), and the increases in NADPH oxidase activity/expression in high-salt-loaded Dahl salt-sensitive rats. N-acetyl-L-cysteine supplement ameliorated plasma and urinary levels of thromboxane B(2) (an end metabolite of thromboxane A(2)), associated with improvement of both the abnormal contraction and the impaired nitric oxide-dependent relaxation in renal arteries. These results revealed that oxidative stress mediates hypertensive changes in Dahl salt-sensitive rats, because thiol antioxidant N-acetyl-L-cysteine attenuated the augmentation of local ROS production by diminishing the elevation of NADPH oxidase expression and ameliorated renal/vascular hypertensive changes.

Acetylcholine↗
PubMed2004

Effect of Feitai on bleomycin-induced pulmonary fibrosis in rats.

The current therapeutic approaches for pulmonary fibrosis, which is characterized by fibroblast proliferation and extracellular matrix remodeling, are unsatisfactory. Feitai, consisting of several herbs, is a folk formula for pulmonary tuberculosis therapy in China. To investigate the effects of Feitai on pulmonary fibrosis, Feitai was administered orally to bleomycin (BLM)-treated rats, and the lung toxicity effects were evaluated according to inflammatory cell count, protein concentration, and lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage fluid (BALF), malondialdehyde level and hydroxyproline content in lung tissue 28 days post-BLM. Serial sections of the lung were stained with hematoxylin and eosin (HE) and Masson trichrome, respectively. The degree of fibrosis was assessed quantitatively using LEICA QWin image analyzer. Results showed that Feitai inhibited BLM-induced lung fibrotic lesions in a dose-dependent manner as reflected by decreased the lung hydroxyproline content and lung fibrosis fraction 28 days after BLM instillation. Treatment with Feitai also significantly ameliorated the BLM-induced lung toxicity effects detected in BALF and lung tissue. The effects in vitro on WI-38 human lung fibroblast cell line showed that Feitai significantly reduced the cell proliferation and transforming growth factor (TGF)-beta stimulated type I collagen synthesis. These results strongly demonstrate that Feitai may be useful in the treatment of pulmonary fibrosis.

Administration, Oral↗
PubMed2004

HS2 enhancer function is blocked by a transcriptional terminator inserted between the enhancer and the promoter.

The HS2 enhancer in the beta-globin locus control region regulates transcription of the globin genes 10-50 kb away. How the HS2 enhancer acts over this distance is not clearly understood. Earlier studies show that in erythroid cells the HS2 enhancer initiates synthesis of intergenic RNAs from sites within and downstream of the enhancer, and the enhancer-initiated RNAs are transcribed through the intervening DNA into the cis-linked promoter and gene. To investigate the functional significance of the enhancer-initiated transcription, here we inserted the lac operator sequence in the intervening DNA between the HS2 enhancer and the epsilon-globin promoter in reporter plasmids and integrated the plasmids into erythroid K562 cells expressing the lac repressor protein. We found that the interposed lac operator/repressor complex blocked the elongation of enhancer-initiated transcription through the intervening DNA and drastically reduced HS2 enhancer function as measured by the level of mRNA synthesized from the epsilon-globin promoter. The results indicate that the tracking and transcription mechanism of the HS2 enhancer-assembled transcriptional machinery from the enhancer through the intervening DNA into the cis-linked promoter can mediate enhancer-promoter interaction over a long distance.

Blotting, Northern↗