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Find video protocols related to scientific articles indexed in Pubmed.
Functional characteristics of reversibly immortalized hepatic progenitor cells derived from mouse embryonic liver.
Cell. Physiol. Biochem.
PUBLISHED: 08-11-2014
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Liver is a vital organ and retains its regeneration capability throughout adulthood, which requires contributions from different cell populations, including liver precursors and intrahepatic stem cells. To overcome the mortality of hepatic progenitors (iHPs) in vitro, we aim to establish reversibly immortalized hepatic progenitor cells from mouse embryonic liver.
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Reversibly Immortalized Mouse Articular Chondrocytes Acquire Long-Term Proliferative Capability while Retaining Chondrogenic Phenotype.
Cell Transplant
PUBLISHED: 05-08-2014
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Cartilage tissue engineering holds great promise for treating cartilaginous pathologies including degenerative disorders and traumatic injuries. Effective cartilage regeneration requires an optimal combination of biomaterial scaffolds, chondrogenic seed cells and biofactors. Obtaining sufficient chondrocytes remains a major challenge due to the limited proliferative capability of primary chondrocytes. Here, we investigate if reversibly immortalized mouse articular chondrocytes (iMACs) acquire long-term proliferative capability while retaining the chondrogenic phenotype. Primary mouse articular chondrocytes (MACs) can be efficiently immortalized with a retroviral vector expressing SV40 large T antigen flanked with Cre/loxP sites. iMACs exhibit long-term proliferation in culture, although the immortalization phenotype can be reversed by Cre recombinase. iMACs express the chondrocyte markers Col2a1 and aggrecan and produce chondroid matrix in micromass culture. iMACs form subcutaneous cartilaginous masses in athymic mice. Histologic analysis and chondroid matrix staining demonstrate that iMACs can survive, proliferate and produce chondroid matrix. The chondrogenic growth factor BMP2 promotes iMACs to produce more mature chondroid matrix resembling mature articular cartilage. Taken together, our results demonstrate that iMACs acquire long-term proliferative capability without losing the intrinsic chondrogenic features of MACs. Thus, iMACs provide a valuable cellular platform to optimize biomaterial scaffolds for cartilage regeneration, to identify biofactors that promote the proliferation and differentiation of chondrogenic progenitors and to elucidate the molecular mechanisms underlying chondrogenesis.
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Bone morphogenetic protein 2 inhibits the proliferation and growth of human colorectal cancer cells.
Oncol. Rep.
PUBLISHED: 04-15-2014
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Colorectal cancer (CRC) is one of the most deadly cancers worldwide. Significant progress has been made in understanding the molecular pathogenesis of CRC, which has led to successful early diagnosis, surgical intervention and combination chemotherapy. However, limited therapeutic options are available for metastatic and/or drug-resistant CRC. While the aberrantly activated Wnt/?-catenin pathway plays a critical initiating role in CRC development, disruption of the bone morphogenetic protein (BMP) pathway causes juvenile polyposis syndrome, suggesting that BMP signaling may play a role in CRC development. However, conflicting results have been reported concerning the possible roles of BMP signaling in sporadic colon cancer. Here, we investigated the effect of BMP2 on the proliferation, migration, invasiveness and tumor growth capability of human CRC cells. Using an adenovirus vector that overexpresses BMP2 and the piggyBac transposon-mediated stable BMP2 overexpression CRC line, we found that exogenous BMP2 effectively inhibited HCT116 cell proliferation and colony formation. BMP2 was shown to suppress colon cancer cell migration and invasiveness. Under a low serum culture condition, forced expression of BMP2 induced a significantly increased level of apoptosis in HCT116 cells. Using a xenograft tumor model, we found that forced expression of BMP2 in HCT116 cells suppressed tumor growth, accompanied by decreased cell proliferation activity. Taken together, our results strongly suggest that BMP2 plays an important inhibitory role in governing the proliferation and aggressive features of human CRC cells.
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Bone morphogenetic protein-9 effectively induces osteo/odontoblastic differentiation of the reversibly immortalized stem cells of dental apical papilla.
Stem Cells Dev.
PUBLISHED: 03-21-2014
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Dental pulp/dentin regeneration using dental stem cells combined with odontogenic factors may offer great promise to treat and/or prevent premature tooth loss. We previously demonstrated that bone morphogenetic protein 9 (BMP9) is one of the most potent factors in inducing bone formation. Here, we investigate whether BMP9 can effectively induce odontogenic differentiation of the stem cells from mouse apical papilla (SCAPs). Using a reversible immortalization system expressing SV40 T flanked with Cre/loxP sites, we demonstrate that the SCAPs can be immortalized, resulting in immortalized SCAPs (iSCAPs) that express mesenchymal stem cell markers. BMP9 upregulates Runx2, Sox9, and PPAR?2 and odontoblastic markers, and induces alkaline phosphatase activity and matrix mineralization in the iSCAPs. Cre-mediated removal of SV40 T antigen decreases iSCAP proliferation. The in vivo stem cell implantation studies indicate that iSCAPs can differentiate into bone, cartilage, and, to lesser extent, adipocytes upon BMP9 stimulation. Our results demonstrate that the conditionally iSCAPs not only maintain long-term cell proliferation but also retain the ability to differentiate into multiple lineages, including osteo/odontoblastic differentiation. Thus, the reversibly iSCAPs may serve as an important tool to study SCAP biology and SCAP translational use in tooth engineering. Further, BMP9 may be explored as a novel and efficacious factor for odontogenic regeneration.
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Targeting BMP9-promoted human osteosarcoma growth by inactivation of notch signaling.
Curr Cancer Drug Targets
PUBLISHED: 02-02-2014
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Osteosarcoma (OS) is the most common primary malignancy of bone and is usually associated with poor prognosis due to its high incidence of metastasis and chemoresistance. Molecular pathogenesis of OS is poorly understood. We previously showed that OS cells are refractory to BMP9-induced osteogenesis and respond favorably to proliferation and tumor growth. Here we investigate if Notch signaling mediates the BMP9-promoted cell proliferation and tumor growth of human osteosarcoma (OS). We find that the expression of Notch1, Notch2, Notch3, DLL1, JAG1 and JAG2 is readily detected in most of the tested OS cell lines. BMP9-promoted OS cell proliferation, migration, and cell cycle S/G2 progression are effectively inhibited by a dominant-negative mutant of Notch1 (dnNotch1) or the ?-secretase inhibitor Compound E (ComE). Furthermore, BMP9-promoted tumor growth and osteolytic lesions in vivo are significantly inhibited by dnNotch1. BMP9 up-regulates the expression of Notch1, Notch3, DLL1, and JAG1 in OS cells. Accordingly, BMP9 stimulation induces a nuclear accumulation of NICD, which is blocked by ComE. Our results demonstrate that BMP9-promoted OS proliferation and tumor growth is at least in part mediated by Notch signaling, suggesting that osteogenic BMPs may function as upstream regulators of Notch signaling in OS tumorigenesis. Thus, pharmacologic intervention of Notch signaling may be explored as a new therapeutic strategy for human OS tumors.
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Genetic polymorphism of interleukin-6 influences susceptibility to HBV-related hepatocellular carcinoma in a male Chinese Han population.
Hum. Immunol.
PUBLISHED: 01-03-2014
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As a multifunctional cytokine, interleukin-6 (IL-6) plays a key role in chronic inflammation as well as tumor growth and progression of hepatitis B virus (HBV) infection. Recent studies have implicated that single nucleotide polymorphism (SNP) -572C>G (rs1800796) located within the promoter region of IL-6 gene was associated with susceptibility to several diseases. Here, a case-control study was undertaken to investigate the association between this polymorphism and HBV-related hepatocellular carcinoma (HCC) susceptibility in a Chinese Han population. A total of 900 patients with chronic HBV infection, including 505 HBV-related HCC patients and 395 HBV infected patients without HCC were enrolled, and rs1800796 polymorphism was genotyped by the TaqMan method and DNA sequencing technology. The results indicated no significant association between rs1800796 polymorphism and the risk of HBV-related HCC in all subjects; however, a significant difference was identified in male subjects. Under the dominant model, male subjects with the G allele (CG/GG) have higher susceptibility to HBV-related HCC than those with CC genotype after adjusting confounding factors (P=0.012, odds ratio [OR] 1.68, 95% confidence interval [95% CI] 1.15-2.42). Our results suggested that rs1800796 polymorphism of IL-6 gene was associated with susceptibility to HBV-related HCC in a male Chinese Han population.
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A Simplified and Versatile System for the Simultaneous Expression of Multiple siRNAs in Mammalian Cells Using Gibson DNA Assembly.
PLoS ONE
PUBLISHED: 01-01-2014
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RNA interference (RNAi) denotes sequence-specific mRNA degradation induced by short interfering double-stranded RNA (siRNA) and has become a revolutionary tool for functional annotation of mammalian genes, as well as for development of novel therapeutics. The practical applications of RNAi are usually achieved by expressing short hairpin RNAs (shRNAs) or siRNAs in cells. However, a major technical challenge is to simultaneously express multiple siRNAs to silence one or more genes. We previously developed pSOS system, in which siRNA duplexes are made from oligo templates driven by opposing U6 and H1 promoters. While effective, it is not equipped to express multiple siRNAs in a single vector. Gibson DNA Assembly (GDA) is an in vitro recombination system that has the capacity to assemble multiple overlapping DNA molecules in a single isothermal step. Here, we developed a GDA-based pSOK assembly system for constructing single vectors that express multiple siRNA sites. The assembly fragments were generated by PCR amplifications from the U6-H1 template vector pB2B. GDA assembly specificity was conferred by the overlapping unique siRNA sequences of insert fragments. To prove the technical feasibility, we constructed pSOK vectors that contain four siRNA sites and three siRNA sites targeting human and mouse ?-catenin, respectively. The assembly reactions were efficient, and candidate clones were readily identified by PCR screening. Multiple ?-catenin siRNAs effectively silenced endogenous ?-catenin expression, inhibited Wnt3A-induced ?-catenin/Tcf4 reporter activity and expression of Wnt/?-catenin downstream genes. Silencing ?-catenin in mesenchymal stem cells inhibited Wnt3A-induced early osteogenic differentiation and significantly diminished synergistic osteogenic activity between BMP9 and Wnt3A in vitro and in vivo. These findings demonstrate that the GDA-based pSOK system has been proven simplistic, effective and versatile for simultaneous expression of multiple siRNAs. Thus, the reported pSOK system should be a valuable tool for gene function studies and development of novel therapeutics.
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Radiofrequency ablation of liver VX2 tumor: experimental results with MR diffusion-weighted imaging at 3.0T.
PLoS ONE
PUBLISHED: 01-01-2014
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To evaluate the value of DWI in detecting the lesions of pre- and post-radiofrequency ablation (RFA) of the rabbit liver VX2 tumors.
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The piggyBac transposon-mediated expression of SV40 T antigen efficiently immortalizes mouse embryonic fibroblasts (MEFs).
PLoS ONE
PUBLISHED: 01-01-2014
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Mouse embryonic fibroblasts (MEFs) are mesenchymal stem cell (MSC)-like multipotent progenitor cells and can undergo self-renewal and differentiate into to multiple lineages, including bone, cartilage and adipose. Primary MEFs have limited life span in culture, which thus hampers MEFs' basic research and translational applications. To overcome this challenge, we investigate if piggyBac transposon-mediated expression of SV40 T antigen can effectively immortalize mouse MEFs and that the immortalized MEFs can maintain long-term cell proliferation without compromising their multipotency. Using the piggyBac vector MPH86 which expresses SV40 T antigen flanked with flippase (FLP) recognition target (FRT) sites, we demonstrate that mouse embryonic fibroblasts (MEFs) can be efficiently immortalized. The immortalized MEFs (piMEFs) exhibit an enhanced proliferative activity and maintain long-term cell proliferation, which can be reversed by FLP recombinase. The piMEFs express most MEF markers and retain multipotency as they can differentiate into osteogenic, chondrogenic and adipogenic lineages upon BMP9 stimulation in vitro. Stem cell implantation studies indicate that piMEFs can form bone, cartilage and adipose tissues upon BMP9 stimulation, whereas FLP-mediated removal of SV40 T antigen diminishes the ability of piMEFs to differentiate into these lineages, possibly due to the reduced expansion of progenitor populations. Our results demonstrate that piggyBac transposon-mediated expression of SV40 T can effectively immortalize MEFs and that the reversibly immortalized piMEFs not only maintain long-term cell proliferation but also retain their multipotency. Thus, the high transposition efficiency and the potential footprint-free natures may render piggyBac transposition an effective and safe strategy to immortalize progenitor cells isolated from limited tissue supplies, which is essential for basic and translational studies.
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Characterization of constitutive promoters for piggyBac transposon-mediated stable transgene expression in mesenchymal stem cells (MSCs).
PLoS ONE
PUBLISHED: 01-01-2014
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Multipotent mesenchymal stem cells (MSCs) can undergo self-renewal and give rise to multi-lineages under given differentiation cues. It is frequently desirable to achieve a stable and high level of transgene expression in MSCs in order to elucidate possible molecular mechanisms through which MSC self-renewal and lineage commitment are regulated. Retroviral or lentiviral vector-mediated gene expression in MSCs usually decreases over time. Here, we choose to use the piggyBac transposon system and conduct a systematic comparison of six commonly-used constitutive promoters for their abilities to drive RFP or firefly luciferase expression in somatic HEK-293 cells and MSC iMEF cells. The analyzed promoters include three viral promoters (CMV, CMV-IVS, and SV40), one housekeeping gene promoter (UbC), and two composite promoters of viral and housekeeping gene promoters (hEFH and CAG-hEFH). CMV-derived promoters are shown to drive the highest transgene expression in HEK-293 cells, which is however significantly reduced in MSCs. Conversely, the composite promoter hEFH exhibits the highest transgene expression in MSCs whereas its promoter activity is modest in HEK-293 cells. The reduced transgene expression driven by CMV promoters in MSCs may be at least in part caused by DNA methylation, or to a lesser extent histone deacetlyation. However, the hEFH promoter is not significantly affected by these epigenetic modifications. Taken together, our results demonstrate that the hEFH composite promoter may be an ideal promoter to drive long-term and high level transgene expression using the piggyBac transposon vector in progenitor cells such as MSCs.
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Adenovirus-mediated efficient gene transfer into cultured three-dimensional organoids.
PLoS ONE
PUBLISHED: 01-01-2014
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Three-dimensional organoids have been recently established from various tissue-specific progenitors (such as intestinal stem cells), induced pluripotent stem cells, or embryonic stem cells. These cultured self-sustaining stem cell-based organoids may become valuable systems to study the roles of tissue-specific stem cells in tissue genesis and disease development. It is thus conceivable that effective genetic manipulations in such organoids may allow us to reconstruct disease processes and/or develop novel therapeutics. Recombinant adenoviruses are one of the most commonly used viral vectors for in vitro and in vivo gene deliveries. In this study, we investigate if adenoviruses can be used to effectively deliver transgenes into the cultured "mini-gut" organoids derived from intestinal stem cells. Using adenoviral vectors that express fluorescent proteins, we demonstrate that adenoviruses can effectively deliver transgenes into the cultured 3-D "mini-gut" organoids. The transgene expression can last at least 10 days in the cultured organoids. As a proof-of-principle experiment, we demonstrate that adenovirus-mediated noggin expression effectively support the survival and self-renewal of mini-gut organoids, while adenovirus-mediated expression of BMP4 inhibits the self-sustainability and proliferation of the organoids. Thus, our results strongly suggest that adenovirus vectors can be explored as effective gene delivery vehicles to introduce genetic manipulations in 3-D organoids.
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Adenovirus-mediated gene transfer in mesenchymal stem cells can be significantly enhanced by the cationic polymer polybrene.
PLoS ONE
PUBLISHED: 01-01-2014
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Mesenchymal stem cells (MSCs) are multipotent progenitors, which can undergo self-renewal and give rise to multi-lineages. A great deal of attentions have been paid to their potential use in regenerative medicine as potential therapeutic genes can be introduced into MSCs. Genetic manipulations in MSCs requires effective gene deliveries. Recombinant adenoviruses are widely used gene transfer vectors. We have found that although MSCs can be infected in vitro by adenoviruses, high virus titers are needed to achieve high efficiency. Here, we investigate if the commonly-used cationic polymer Polybrene can potentiate adenovirus-mediated transgene delivery into MSCs, such as C2C12 cells and iMEFs. Using the AdRFP adenovirus, we find that AdRFP transduction efficiency is significantly increased by Polybrene in a dose-dependent fashion peaking at 8 ?g/ml in C2C12 and iMEFs cells. Quantitative luciferase assay reveals that Polybrene significantly enhances AdFLuc-mediated luciferase activity in C2C12 and iMEFs at as low as 4 ?g/ml and 2 ?g/ml, respectively. FACS analysis indicates that Polybrene (at 4 ?g/ml) increases the percentage of RFP-positive cells by approximately 430 folds in AdRFP-transduced iMEFs, suggesting Polybrene may increase adenovirus infection efficiency. Furthermore, Polybrene can enhance AdBMP9-induced osteogenic differentiation of MSCs as early osteogenic marker alkaline phosphatase activity can be increased more than 73 folds by Polybrene (4 ?g/ml) in AdBMP9-transduced iMEFs. No cytotoxicity was observed in C2C12 and iMEFs at Polybrene up to 40 ?g/ml, which is about 10-fold higher than the effective concentration required to enhance adenovirus transduction in MSCs. Taken together, our results demonstrate that Polybrene should be routinely used as a safe, effective and inexpensive augmenting agent for adenovirus-mediated gene transfer in MSCs, as well as other types of mammalian cells.
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Rather than Rs1800796 Polymorphism, Expression of Interleukin-6 is Associated with Disease Progression of Chronic HBV Infection in a Chinese Han Population.
Dis. Markers
PUBLISHED: 08-14-2013
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Interleukin-6 plays an important role in chronic inflammation as well as tumor growth and progression. Here, a case-control study was undertaken to investigate the association of rs1800796 polymorphism of IL-6 gene and serum levels with disease progression of chronic HBV infection. Rs1800796 polymorphism was genotyped in 641 Chinese Han patients with chronic HBV infection, including 23 IT, 25 IC, 292 CHB, 153 LC, and 148 HCC patients and 265 healthy controls. Serum IL-6 levels were measured in 23 IT, 25 IC, 47 CHB, 41 LC, and 49 HCC patients and 45 healthy controls, and the classifications of HCC were accorded to BCLC staging system. We found no significant association between rs1800796 polymorphism and disease progression of chronic HBV infection; however, serum IL-6 levels showed significant statistical differences between patients with CHB, LC, and HCC. Moreover, statistical differences can be observed in patients with terminal stage HCC compared with those of early to intermediate or advanced stage HCC. Our findings suggest that rs1800796 polymorphism unlikely contribute significantly to affect the progression of chronic HBV infection, and serum IL-6 levels can act as a useful indicator for disease progression and severity of chronic HBV infection.
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Posterior mediastinal tuberculous lymphadenitis with dysphagia as the main symptom: a case report and literature review.
J Thorac Dis
PUBLISHED: 06-21-2013
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Mediastinal tuberculous lymphadenitis (MTL) is mostly seen in primary tuberculosis in children, uncommon observed in adults. It usually presents the toxic symptoms of tuberculosis but rarely with symptoms characteristic of esophageal compression, such as dysphagia. Such patients can easily be misdiagnosed as esophageal neoplasm and get delayed or faulty treatment.
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Modulation of ?-Catenin Signaling by the Inhibitors of MAP Kinase, Tyrosine Kinase, and PI3-Kinase Pathways.
Int J Med Sci
PUBLISHED: 01-01-2013
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Aberrant activation of ?-catenin signaling plays an important role in human tumorigenesis. However, molecular mechanisms behind the ?-catenin signaling deregulation are mostly unknown because genetic alterations in this pathway only account for a small fraction of tumors. Here, we investigator if other major pathways can regulate ?-catenin signaling activity. By employing a panel of chemical activators and/or inhibitors of several cellular signaling pathways, we assess these modulators effects on luciferase reporter driven by ?-catenin/TCF4-responsive elements. We find that lithium-stimulated ?-catenin activity is synergistically enhanced by protein kinase C activator PMA. However, ?-catenin-regulated transcriptional (CRT) activity is significantly inhibited by casein kinase II inhibitor DRB, MEK inhibitor PD98059, G-proteins and their receptor uncoupling agent suramin, protein tyrosine kinase inhibitor genistein, and PI-3 kinase inhibitor wortmannin, suggesting that these cellular pathways may participate in regulating ?-catenin signaling. Interestingly, the Ca(++)/calmodulin kinase II inhibitor HDBA is shown to activate ?-catenin activity at low doses. Furthermore, Wnt3A-stimulated and constitutively activated CRT activities, as well as the intracellular accumulation of ?-catenin protein in human colon cancer cells, are effectively suppressed by PD98059, genistein, and wortmannin. We further demonstrate that EGF can activate TCF4/?-catenin activity and induce the tyrosine phosphorylation of ?-catenin protein. Thus, our results should provide important insights into the molecular mechanisms underlying Wnt/?-catenin activation. This knowledge should facilitate our efforts to develop efficacious and novel therapeutics by targeting these pathways.
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Identification of adiponectin receptor agonist utilizing a fluorescence polarization based high throughput assay.
PLoS ONE
PUBLISHED: 01-01-2013
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Adiponectin, the adipose-derived hormone, plays an important role in the suppression of metabolic disorders that can result in type 2 diabetes, obesity, and atherosclerosis. It has been shown that up-regulation of adiponectin or adiponectin receptor has a number of therapeutic benefits. Given that it is hard to convert the full size adiponectin protein into a viable drug, adiponectin receptor agonists could be designed or identified using high-throughput screening. Here, we report on the development of a two-step screening process to identify adiponectin agonists. First step, we developed a high throughput screening assay based on fluorescence polarization to identify adiponectin ligands. The fluorescence polarization assay reported here could be adapted to screening against larger small molecular compound libraries. A natural product library containing 10,000 compounds was screened and 9 hits were selected for validation. These compounds have been taken for the second-step in vitro tests to confirm their agonistic activity. The most active adiponectin receptor 1 agonists are matairesinol, arctiin, (-)-arctigenin and gramine. The most active adiponectin receptor 2 agonists are parthenolide, taxifoliol, deoxyschizandrin, and syringin. These compounds may be useful drug candidates for hypoadiponectin related diseases.
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Hypoxia induces genomic DNA demethylation through the activation of HIF-1? and transcriptional upregulation of MAT2A in hepatoma cells.
Mol. Cancer Ther.
PUBLISHED: 04-01-2011
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Hypoxia-inducible factor 1 (HIF-1) emerges as a crucial player in tumor progression. However, its role in hepatocellular carcinoma (HCC), especially its relation with global DNA methylation patterns in HCC under hypoxic tumor microenvironment is not completely understood. Methionine adenosyltransferase 2A (MAT2A) maintains the homeostasis of S-adenosylmethionine (SAM), a critical marker of genomic methylation status. In this study, we investigated the link between HIF-1? and MAT2A as a mechanism responsible for the change in genomic DNA methylation patterns in liver cancer under hypoxia conditions. Our results showed that hypoxia induces genomic DNA demethylation in CpG islands by reducing the steady-state SAM level both in vitro and in vivo. In addition, HIF-1? and MAT2A expression is correlated with tumor size and TNM stage of liver cancer tissues. We further showed that hypoxia-induced MAT2A expression is HIF-1? dependent and requires the recruitment of p300 and HDAC1. We also identified an authentic consensus HIF-1? binding site in MAT2A promoter by site-directed mutagenesis, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay. Taken together, we show for the first time that hypoxia induces genomic DNA demethylation through the activation of HIF-1? and transcriptional upregulation of MAT2A in hepatoma cells. These findings provide new insights into our understanding of the molecular link between genomic DNA methylation and tumor hypoxia in HCC.
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Molecular characterization, structural analysis and determination of host range of a novel bacteriophage LSB-1.
Virol. J.
PUBLISHED: 07-12-2010
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Bacteriophages (phages) are widespread in the environment and play a crucial role in the evolution of their bacterial hosts and the emergence of new pathogens.
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The association of SULT1A1 codon 213 polymorphism and breast cancer susceptibility: meta-analysis from 16 studies involving 23,445 subjects.
Breast Cancer Res. Treat.
PUBLISHED: 05-10-2010
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Epidemiological studies on the association between SULT1A1 codon 213 polymorphism and breast cancer risk are inconclusive. In order to derive a more precise estimation of the association, a meta-analysis was conducted in this article. Sixteen studies including 9,881 cases and 13,564 controls were collected for SULT1A1 codon 213 polymorphism by searching the databases of Medline, PubMed, Embase, and ISI Web of Knowledge. The strength of association between SULT1A1 codon 213 polymorphism and breast cancer susceptibility was assessed by calculating crude ORs with 95% CIs. When all the 21 studies were pooled into the meta-analysis, there was no evidence for significant association between SULT1A1 codon 213 polymorphism and breast cancer susceptibility (for Arg/Arg versus Arg/His: OR = 0.999, 95% CI = 0.941-1.061; for Arg/Arg versus His/His: OR = 1.121, 95% CI = 1.013-1.242; for dominant model: OR = 1.128, 95% CI = 1.01-1.26; for recessive model: OR = 1.151, 95% CI = 0.950-1.394). In the subgroup analysis by the source of controls, significant increased risk was found for hospital-based studies (for Arg/Arg versus Arg/His: OR = 1.173, 95% CI = 1.000-1.376; for Arg/Arg versus His/His: OR = 1.600, 95% CI = 1.134-2.256; for dominant model: OR = 1.269, 95% CI = 1.134-2.256; for recessive model: OR = 1.664, 95% CI = 1.070-2.588). In summary, the meta-analysis suggests that SULT1A1 codon 213 polymorphism may be associated with the hospital-based studies. However, large number of samples and representative hospital-based studies with homogeneous breast cancer patients and well-matched controls are warranted to confirm this finding.
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Synthesis and characterization of graft copolymer of chitosan and polyethylene glycol.
Mol. Biol. Rep.
PUBLISHED: 03-22-2010
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MPEG was modified with 1,1-carbonyldiimidazole, then the activated MPEG reacted with primary amino groups of chitosan. Synthesize the graft copolymer of chitosan and polyethylene glycol in two steps. The structure of the copolymer was characterized by FT-IR and 1H-NMR. It agrees with the PEG content of classical stealth nanoparticles materials. The X-ray diffraction and DSC analysis proved that the crystallinity of the copolymer increased. It is a promising material for the stealth nanoparticles. It is a potential new carrier for the drug delivery systems of long-circulation and solid carcinoma.
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Experimental investigation of the immunoregulatory and anti-inflammatory effects of the traditional Chinese medicine "Li-Yan Zhi-Ke Granule" for relieving chronic pharyngitis in rats.
Mol. Biol. Rep.
PUBLISHED: 03-15-2010
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Chronic pharyngitis, a chronic inflammation of the pharyngeal mucous membrane and submucous lymphoid tissues, is often caused by unsatisfactory treatment of acute pharyngitis or repeated occurrences of upper respiratory tract infection and is related to a high-dust environment. Traditional herbal pharmacotherapy is well known for combining plant species to create complex phytochemical mixtures in the attempt to ameliorate pathophysiological processes. The aim of current study is to investigate the effect of immunoregulation and anti-inflammation with the traditional Chinese medicine (TCM) "Li-Yan Zhi-Ke Granule" in rats. Determination of serum hemolysin and the carbon particle clearance test were performed. The results demonstrate that administration of the TCM "Li-Yan Zhi-Ke Granule" may improve the effect of phagocytosis by mononuclear macrophages and immune function in rats, and may also increase the immunoregulatory and anti-inflammatory responses of rats with chronic pharyngitis. This traditional drug could relieve the symptoms of sore throat and cough in rats with chronic pharyngitis.
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Chemokine CCL3 facilitates the migration of hepatoma cells by changing the concentration intracellular Ca.
Hepatol. Res.
PUBLISHED: 03-04-2010
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Aim: Recurrence and metastasis are the major factors associated with the poor prognosis of hepatocellular carcinoma (HCC). It was confirmed that multiple chemokines and their receptors are related to the progression and metastasis of HCC. The aim of this research was to conduct an investigation into whether macrophage inflammatory protein-1alpha/CCL3, and its receptor CCR1 play a role in HCC invasion and metastasis. Methods: We used reverse transcription polymerase chain reaction, immunocytochemistry and flow cytometry to detect CCR1 mRNA and protein expression in the four hepatoma cell lines HepG2, Hep3B, HLE and HLF; and we conducted a microscope cell migration experiment to observe the pseudopodia formation and mobility of the hepatoma cells. The concentration of intracellular calcium was measured by fluorescence microscopy. Results: CCR1 mRNA and protein were positively expressed in the four hepatoma cell lines HepG2, Hep3B, HLE and HLF. Following CCL3 stimulation, obvious pseudopodia formation of hepatoma cells was observed using a fluorescence microscope. The cell migration experiment showed that after incubation with CCL3, the number of Hep3B cells which passed through the polycarbonate microporous filter membranes increased to an obvious extent. After CCL3 incubation, the intracellular Ca(2+) level of the Hep3B cells increased to an obvious extent. Conclusion: Chemokine CCL3 facilitates the migration of hepatoma by changing the concentration intracellular Ca(2+). The CCL3-CCR1 axis may play an important role in HCC invasion and metastasis. It may also be a potential target for HCC therapy or for prevention of the recurrence and metastasis of HCC.
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Differential proteomics identification of HSP90 as potential serum biomarker in hepatocellular carcinoma by two-dimensional electrophoresis and mass spectrometry.
Int J Mol Sci
PUBLISHED: 01-11-2010
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The aim of the current study is to identify the potential biomarkers involved in Hepatocellular carcinoma (HCC) carcinogenesis. A comparative proteomics approach was utilized to identify the differentially expressed proteins in the serum of 10 HCC patients and 10 controls. A total of 12 significantly altered proteins were identified by mass spectrometry. Of the 12 proteins identified, HSP90 was one of the most significantly altered proteins and its over-expression in the serum of 20 HCC patients was confirmed using ELISA analysis. The observations suggest that HSP90 might be a potential biomarker for early diagnosis, prognosis, and monitoring in the therapy of HCC. This work demonstrates that a comprehensive strategy of proteomic identification combined with further validation should be adopted in the field of cancer biomarker discovery.
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Segregation distortion detected in six rice F2 populations generated from reciprocal hybrids at three altitudes.
Genet Res (Camb)
PUBLISHED: 11-20-2009
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This paper presents investigations of segregation distortion of six rice F2 populations generated from reciprocal F1 hybrids grown at three locations varied at altitudes from 400 to 2200 m. The F1s were derived from reciprocal crosses between cv. XMG, which is a japonica landrace traditionally grown at 2650 m altitude, and cv. N34, which is a japonica restorer possessing a fertility restoring (Rf) gene and cytoplasm of male sterility (CMS) donated by an indica cultivar. Among nine morphological traits of the F2 populations, only one was in normal distribution, eight were distorted in all or at least one population. Out of 16 polymorphic PCR markers, 10 markers distributed on 7 chromosomes were significantly distorted. Among these markers, RMAN7 and RM257 were distorted in both of the reciprocal populations, which suggested that nuclear genes had strong effects on segregation distortion. The other makers were distorted only in the populations with cytoplasm donated by XMG or N34. The results indicated that segregation of DNA markers was affected by cytoplasm background. Segregation distribution was also affected by altitude, since segregation distortions of most of the markers were detected not in all the three populations generated from F1 grown at the three altitudes, but only in one population from F1 grown at one altitude. Marker M45461, which is located within Rf-1 locus, was severely distorted towards N34 in all the populations with cytoplasm donated by N34, but not in the populations with cytoplasm provided by XMG. The results indicated that interaction between CMS and Rf gene had strong effects on distortion. Results of this study indicated that japonica cytoplasm did not cause distortion favouring a special parent, but indica cytoplasm made distortion favouring a maternal parent. The results suggested that indica cytoplasm was not well compatible with japonica nuclear background, while japonica cytoplasm did not have such trouble with indica nuclei. This study also found that the six F2 populations were divergent into two groups due to difference of cytoplasm background.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.