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Find video protocols related to scientific articles indexed in Pubmed.
Total synthesis and determination of the absolute configuration of rakicidin a.
J. Am. Chem. Soc.
PUBLISHED: 10-24-2014
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Rakicidin A is a cyclic depsipeptide that has exhibited unique growth inhibitory activity against chronic myelogenous leukemia stem cells. Furthermore, rakicidin A has five chiral centers with unknown stereochemical assignment, and thus, can be represented by one of 32 possible stereoisomers. To predict the most probable stereochemistry of rakicidin A, calculations and structural comparison with natural cyclic depsipeptides were applied. A total synthesis of the proposed structure was subsequently completed and highlighted by the creation of a sterically hindered ester bond (C1-C15) through trans-acylation from an easily established isomer (C1-C13). The analytic data of the synthetic target were consistent with that of natural rakicidin A, and then the absolute configuration of rakicidin A was assigned as 2S, 3S, 14S, 15S, 16R. This work suggests strategies for the determination of unknown chiral centers in other cyclic depsipeptides, such as rakicidin B, C, D, BE-43547, and vinylamycin, and facilitates the investigations of rakicidin A as an anticancer stem cell agent.
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Tumor suppressor FOXO3 regulates ribonucleotide reductase subunit RRM2B and impacts on survival of cancer patients.
Oncotarget
PUBLISHED: 06-21-2014
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The role of Ribonucleotide reductase (RR) subunits in different cancers has been intensively studied in our laboratory. RRM2B was identified as a p53-inducible RR subunit that involves in various critical cellular mechanisms such as cell cycle regulation, DNA repair and replication, and mitochondrial homeostasis, etc. However, little is known about the p53-independent regulation of RRM2B in cancer pathology. In this study, we discovered tumor suppressor FOXO3 as the novel regulator of RRM2B. FOXO3 directly bound to and transcriptionally activated the promoter of RRM2B, and induced the expression of RRM2B at RNA and protein levels. Moreover, Overexpression of RRM2B and/or FOXO3 inhibited the proliferation of cancer cells. The cancer tissue microarray data also demonstrated a strong correlation between the co-expression of FOXO3 plus RRM2B and increased disease survival and reduced recurrence or metastasis in lung cancer patients. Our results suggest a novel regulatory control of RRM2B function, and imply the importance of FOXO signaling pathway in DNA replication modulation. This study provides the first time evidence that RRM2B is transcriptionally and functionally regulated independent of p53 pathway by FOXO3, and it establishes that FOXO3 and RRM2B could be used as predictive biomarkers for cancer progression.
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Comparison of telbivudine efficacy in treatment-naive patients with hepatitis B virus-related compensated and decompensated cirrhosis in 96 weeks.
Eur J Gastroenterol Hepatol
PUBLISHED: 02-27-2014
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Data are limited for comparison of the long-term efficacy of telbivudine (LdT) between hepatitis B virus (HBV)-related compensated and decompensated cirrhosis. The aim of this study was to compare the efficacy of LdT in treatment-naive patients with HBV-related compensated and decompensated cirrhosis in 96 weeks.
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Frequent overexpression of HMGA2 in human atypical teratoid/rhabdoid tumor and its correlation with let-7a3/let-7b miRNA.
Clin. Cancer Res.
PUBLISHED: 01-14-2014
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Atypical teratoid/rhabdoid tumors (AT/RT) are highly aggressive pediatric malignancies characterized by biallelic inactivation of the SMARCB1 tumor suppressor gene. We searched for novel genomic aberrations by investigating the copy number and expression alterations of let-7a3/let-7b microRNA (miRNA) and correlated these with expression of high-mobility group AT-hook 2 (HMGA2) oncoprotein, a target of let-7 miRNA family, in 18 AT/RT samples to elucidate potential roles of HMGA2 in the pathogenesis of AT/RT.
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Mixotrophic cultivation of microalgae for biodiesel production: status and prospects.
Appl. Biochem. Biotechnol.
PUBLISHED: 01-02-2014
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Biodiesel from microalgae provides a promising alternative for biofuel production. Microalgae can be produced under three major cultivation modes, namely photoautotrophic cultivation, heterotrophic cultivation, and mixotrophic cultivation. Potentials and practices of biodiesel production from microalgae have been demonstrated mostly focusing on photoautotrophic cultivation; mixotrophic cultivation of microalgae for biodiesel production has rarely been reviewed. This paper summarizes the mechanisms and virtues of mixotrophic microalgae cultivation through comparison with other major cultivation modes. Influencing factors of microalgal biodiesel production under mixotrophic cultivation are presented, development of combining microalgal biodiesel production with wastewater treatment is especially reviewed, and bottlenecks and strategies for future commercial production are also identified.
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Anticancer activity of oncolytic adenoviruses carrying p53 is augmented by 11R in gallbladder cancer cell lines in vitro and in vivo.
Oncol. Rep.
PUBLISHED: 02-21-2013
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Gallbladder cancer (GBC) is a rare disease associated with an extremely poor patient prognosis, and occasionally, aberrant expression of p53 is present. Considering that p53 is one of the most widely studied tumor?suppressor genes, we used a cell-penetrating peptide, 11R, to enhance the transferring efficiency of the oncolytic adenovirus carrying the p53 gene by constructing SG7605-11R-p53, a gene-viral therapy system which has higher specificity, enhanced safety, and efficacy. After infection with SG7605-11R-p53 at a multiplicity of infection (MOI) of 1 PFU/cell in vitro, the survival rate of EH-GB1 cells was lower than 50%, and that of EH-GB2 cells was lower than 40%, while the survival rate was higher than 90% for BJ human fibroblast cells, demonstrating that SG7605-11R-p53 has potent specific cytotoxicity against GBC cells. The tumor growth was greatly inhibited in nude mice bearing EH-GB2 xenografts when the total dose of SG7605-11R-p53 was 1x109 PFU, and terminal dUTP nick end-labeling (TUNEL) revealed that the apoptotic rate of cancer cells was 66.75±6.702%. Compared with existing gene therapy with long-standing shortcomings, our new system offers an additional option for patients with advanced GBC and other cancers who may not be suitable for chemotherapy, radiotherapy or who are not indicated for surgical treatment.
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OCT4 increases BIRC5 and CCND1 expression and promotes cancer progression in hepatocellular carcinoma.
BMC Cancer
PUBLISHED: 02-18-2013
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OCT4 and BIRC5 are preferentially expressed in human cancer cells and mediate cancer cell survival and tumor maintenance. However, the molecular mechanism that regulates OCT4 and BIRC5 expression is not well characterized.
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Identification of novel mutations of TP53, ALK and RET gene in metastatic thymic squamous cell carcinoma and its therapeutic implication.
Lung Cancer
PUBLISHED: 01-31-2013
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Thymic tumors are epithelial tumors of the thymus for which multimodal therapies are often ineffective because of a lack of standardized regimens. Due to the low incidence, the molecular pathology and genomic abnormalities of thymic epithelial tumors are largely unknown. In this study, we report our comprehensively genomic study on a case of metastatic thymic tumor. Using next generation deep DNA sequencing technology, we sequenced 190 segments of 46 cancer genes of the cancer genome to cover 739 COSMIC mutations in 604 loci. Among these sequenced cancer genes, we identified that three low frequency (~10% of cells) mutations in the TP53 gene (c.782+1G>T), ALK gene (c.3551C>T), and RET gene (c.2651A>T). To the best of our knowledge, this is the first study to show those mutations in thymic tumor. Of note, our study further indicates comprehensive molecular analysis may facilitate development of novel diagnostic and therapeutic strategies for thymic tumors.
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Characterization of two novel cell lines with distinct heterogeneity derived from a single human bile duct carcinoma.
PLoS ONE
PUBLISHED: 01-30-2013
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Intratumoral heterogeneity reflects subclonal diversity and accounts for a variety of clinically defined phenotypes including the development of drug resistance and recurrence. However, intratumoral heterogeneity of bile duct carcinoma (BDC) is rarely studied.
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Influence of growth manner on nitrifying bacterial communities and nitrification kinetics in three lab-scale bioreactors.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 09-11-2011
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The effects of growth type, including attached growth, suspended growth, and combined growth, on the characteristics of communities of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) were studied in three lab-scale Anaerobic/Anoxic(m)-Oxic(n) (AmOn) systems. These systems amplified activated sludge, biofilms, and a mixture of activated sludge and biofilm (AS-BF). Identical inocula were adopted to analyze the selective effects of mixed growth patterns on nitrifying bacteria. Fluctuations in the concentration of nitrifying bacteria over the 120 days of system operation were analyzed, as was the composition of nitrifying bacterial community in the stabilized stage. Analysis was conducted using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR. According to the DGGE patterns, the primary AOB lineages were Nitrosomonas europaea (six sequences), Nitrosomonas oligotropha (two sequences), and Nitrosospira (one sequence). The primary subclass of NOB community was Nitrospira, in which all identified sequences belonged to Nitrospira moscoviensis (14 sequences). Nitrobacter consisted of two lineages, namely Nitrobacter vulgaris (three sequences) and Nitrobacter alkalicus (two sequences). Under identical operating conditions, the composition of nitrifying bacterial communities in the AS-BF system demonstrated significant differences from those in the activated sludge system and those in the biofilm system. Major varieties included several new, dominant bacterial sequences in the AS-BF system, such as N. europaea and Nitrosospira and a higher concentration of AOB relative to the activated sludge system. However, no similar differences were discovered for the concentration of the NOB population. A kinetic study of nitrification demonstrated a higher maximum specific growth rate of mixed sludge and a lower half-saturation constant of mixed biofilm, indicating that the AS-BF system maintained relatively good nitrifying ability.
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[Construction of adenovirus carrying dual-target shRNA for Oct-4 and Survivin and its inhibitory effect on human hepatocellular carcinoma cells].
Sheng Wu Gong Cheng Xue Bao
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The transcriptional factor Oct-4 and Survivin are the key regulatory factors in cancer cell proliferation and mitosis. A dual cancer-specific shRNA adenovirus vector, Ad5-Dual-shRNA, targeting Oct-4 and Survivin genes was constructed by molecular cloning and recombination. After cells were infected with virus, hepatocellular carcinoma cell line EHBH-H1 was used for detecting the expression of Oct-4 and Survivin proteins by Western blotting. The viral cytotoxic effect on cancer cells was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay in vitro, and the inhibition effect on tumor xenografts was observed in nude mice. The results showed that the expression of Oct-4 and Survivin in cancer cell line EHBH-H1 could be silenced markedly by Ad5-Dual-shRNA. In MTT and animal experiments, Ad5-Dual-shRNA also represented much stronger anti-tumor effect on tumor growth than Ad5-Surv-shRNA and Ad5-Oct4-shRNA. From this research we can draw a conclusion that the cancer-specific adenovirus vector expressing dual-shRNA targeting Oct-4 and Survivin genes may provide us a more effective, specific and convenient gene therapy method.
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Down-regulation of miR-214 contributes to intrahepatic cholangiocarcinoma metastasis by targeting Twist.
FEBS J.
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miRNAs play an important role in many human diseases, including cancer metastasis. However, the mechanisms by which miRNAs regulate intrahepatic cholangiocarcinoma metastasis remain poorly understood. In the present study, we assayed the expression level of miR-214 in intrahepatic cholangiocarcinoma tissues by real-time PCR, and defined the target gene and biological function by luciferase reporter assay and Western blot analysis. We found that the miR-214 levels were remarkably decreased in metastatic intrahepatic cholangiocarcinoma tissues compared to non-metastatic tissues. Inhibition of miR-214 levels by its inhibitor promoted metastasis of human intrahepatic cholangiocarcinoma cell. We further demonstrated that down-regulation of miR-214 increased the transcript levels of the epithelial-mesenchymal transition-associated gene Twist, and then decreased E-cadherin levels. We confirmed that down-regulation of miR-214 promoted the epithelial-mesenchymal transition by directly targeting the Twist gene. These results suggest an important role for miR-214 in regulating metastasis of intrahepatic cholangiocarcinoma, and potential application of miR-214 in intrahepatic cholangiocarcinoma therapy.
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Salmeterol attenuates the inflammatory response in asthma and decreases the pro-inflammatory cytokine secretion of dendritic cells.
Cell. Mol. Immunol.
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Salmeterol is a long-acting ?2-agonist that activates adenylate cyclase, causing long-lasting bronchodilation and has been used for many years to control asthma. However, little information is available about the immunoregulatory effects of salmeterol. We found that salmeterol decreases the production of pro-inflammatory cytokines in a model of allergen-challenged mice that expressed tumor-necrosis factor-alpha, interleukin-1 and interleukin-6. Dendritic cells (DCs) are antigen-presenting cells and act as sentinels in the airway. We found that salmeterol (10(-5) mol/l) reduced the inflammation caused by lipopolysaccharide (0.1 µg/ml) in activated murine bone marrow-derived DCs. Moreover, western blots demonstrated that this protective effect was mediated partially by inhibiting signaling through the nuclear factor-kappa B (NF-?B), mitogen-activated protein kinase (MAPK) pathways and dramatically decreased levels of p-ERK. We suggest that salmeterol regulates the inflammation of allergen-induced asthma by modulating DCs. In conclusion, we provide evidence that DCs are the target immune cells responsible for the action of salmeterol against asthma.
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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.

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

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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.