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Find video protocols related to scientific articles indexed in Pubmed.
Wave structure function and spatial coherence radius of plane and spherical waves propagating through oceanic turbulence.
Opt Express
PUBLISHED: 11-18-2014
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The analytical formulae for the wave structure functions (WSF) and the spatial coherence radius of plane and spherical waves propagating through oceanic turbulence are derived. It is found that the Kolmogorov five-thirds power law of WSF is also valid for oceanic turbulence in the inertial range. The changes of the WSF and the spatial coherence radius versus different parameters of oceanic turbulence are examined.
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Ultrashort pulse generation by semiconductor mode-locked lasers at 760 nm.
Opt Express
PUBLISHED: 11-18-2014
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We demonstrate the first semiconductor mode-locked lasers for ultrashort pulse generation at the 760 nm waveband. Multi-section laser diodes based on an AlGaAs multi-quantum-well structure were passively mode-locked, resulting in the generation of pulses at around 766 nm, with GHz (with different laser cavity lengths of 1.8 mm and 1.5 mm, respectively). The influence of the bias conditions on the mode-locking characteristics was investigated for these new lasers, revealing trends which can be ascribed to the interplay of dynamical processes in the saturable absorber and gain sections. It was also found that the front facet reflectivity played a key role in the stability of mode-locking and the occurrence of self-pulsations. These lasers hold significant promise as light sources for multi-photon biomedical imaging, as well as in other applications such as frequency conversion into the ultraviolet and radio-over-fibre communications.
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Generation of cytotoxic T lymphocytes specific for native or modified peptides derived from the epidermal growth factor receptor pathway substrate 8 antigen.
Cancer Immunol. Immunother.
PUBLISHED: 10-23-2014
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The ideal tumor antigen for the development of a cancer immunotherapy is one that is expressed only in tumor cells. The epidermal growth factor receptor pathway substrate 8 gene (Eps8) might be an effective antigen for cancer immunotherapy as it is overexpressed in a variety of cancer cells but not in normal tissues. In this study, the potential utility of an Eps8-derived immunotherapy was tested in vitro and in vivo. Three computer-based algorithms were used to design eight Eps8 native epitopes with potentially high binding affinity to the HLA-A2.1 molecule, which is found at a high frequency in the Chinese population. Of these eight, three peptides with a moderate affinity to the HLA-A2.1 molecule were modified at anchor residue positions to achieve stronger immunogenicity. These four modified peptides displayed stronger binding affinity to HLA-A2.1 molecules on T2 cells and a lower dissociation rate. In functional assays with human PBMCs in vitro and in HLA-A2.1/K(b) transgenic mice in vivo, CTLs primed by each native and modified peptide secreted IFN-? and were toxic to cancer cells from a variety of tissue types in an HLA-A2.1-restricted and Eps8-specific manner. p101-109-2L and p276-284-1Y9V were superior to other modified and native epitopes both in vitro and in vivo. These results indicate that employing the native and modified epitopes identified here in Eps8-based immunotherapy for HLA-A2.1 positive cancer patients may result in efficient anticancer immune responses for diverse tumor types.
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[The relevance of leukotriene D4 synthase gene A(-444)C polymorphism to clinical responsiveness of leukotriene receptor antagonist in patients with allergic rhinitis].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 10-22-2014
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To investigate the leukotriene D4 synthase gene A (LTD4S A)-444 C polymorphism in persistent allergic rhinitis (AR) of Chinese Han nationality and to evaluate its relevance to clinical responsiveness of leukotriene receptor antagonist.
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Phospholipid Transfer Protein Destabilizes Mouse Atherosclerotic Plaque.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 10-16-2014
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Phospholipid transfer protein (PLTP) accelerates the development of atherosclerosis in mouse models. We examined the role of PLTP in atherosclerotic plaque stability.
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No evidence of association between variant rs2075650 in lipid metabolism-related locus APOE/TOMM40 and advanced age-related macular degeneration in Han Chinese population.
Exp. Biol. Med. (Maywood)
PUBLISHED: 10-12-2014
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Age-related macular degeneration (AMD) is a late-onset, neurodegenerative disease. Genes related to lipid metabolism are important in AMD pathogenesis. Recently, a variant rs2075650 located in lipid metabolism-related locus APOE/TOMM40 was identified to be associated with advanced AMD and early AMD, respectively, in two genome-wide association studies with European ancestry, while no association study between rs2075650 and overall advanced AMD in Chinese population has been conducted before. We evaluated the potential effect of this variant on advanced AMD in a Han Chinese cohort with 204 advanced AMD patients and 1536 healthy controls. The results suggested that rs2075650 was neither associated with advanced AMD in allele level (P?=?0.348) nor in genotype level (P?=?0.890 under additive model with age and sex adjusted). In conclusion, our study did not confirm the impact of rs2075650 on advanced AMD risk, indicating that rs2075650 is unlikely a superior marker for APOE/TOMM40 susceptible region with advanced AMD in Han Chinese population.
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Inhibition of Foxp3 in cancer cells induces apoptosis of thyroid cancer cells.
Mol. Cell. Endocrinol.
PUBLISHED: 09-25-2014
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Foxp3+ regulatory T cells (Tregs) in lymphocytes facilitate the thyroid tumor growth and invasion. Very limited information is available on Foxp3 expression in thyroid cancer cells and its function is totally unknown. This study demonstrated that Foxp3 expression was increased in thyroid cancer cells. Inhibition of Foxp3 decreased cell proliferation and migration, but increased apoptosis, suggesting a positive role of Foxp3 in cancer growth. Interestingly, Foxp3 inhibition enhanced PPAR? expression and activity. In addition, Foxp3 inhibition downregulated NF-?B subunit p65 and cyclin D1 but upregulated caspase-3 levels. These molecular changes are in line with Foxp3 shRNA-mediated alteration of cell functions. Collectively, our study demonstrates that thyroid cancer cells express a high level of functional Foxp3 and that the inhibition of the Foxp3 suppresses the proliferation and migration but promotes apoptosis, suggesting that targeting Foxp3 in thyroid cancer cells may offer a novel therapeutic option for thyroid cancer.
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[Clinical analysis of total aortic arch reconstruction with a novel individualized combined branched stent grafting technique for patients with Stanford A aortic dissection].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 09-16-2014
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To compare the clinical efficacy between total aortic arch reconstruction with a individualized combined branched stent grafting technique and total aortic arch replacement combined with stented elephant trunk implantation for patients with Stanford A aortic dissection.
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Specific Genetic Influences on Nighttime Blood Pressure.
Am. J. Hypertens.
PUBLISHED: 09-11-2014
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Nighttime blood pressure (BP) has been shown to be superior to daytime BP in predicting hypertension related target organ damage and cardiac mortality. In our Georgia Cardiovascular Twin Study, we showed that apart from the genes that also influence daytime BP, specific genetic determinants explained 44% and 67% of the nighttime systolic BP (SBP) and diastolic BP (DBP) heritabilities, respectively. Here, we determined whether these results could be confirmed in a much larger twin cohort of young adults with 24-hour ambulatory BP measurements.
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Younger age of onset and multiple primary lesions associated with esophageal squamous cell carcinoma cases with a positive family history of the cancer suggests genetic predisposition.
Chin. Med. J.
PUBLISHED: 08-23-2014
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Previous epidemiological studies have consistently found a positive family history of esophageal cancer is associated with a significantly increased risk of the cancer. However, whether the elevated risk could be attributed to common household exposure or inherited susceptibility is uncertain. This study aimed to highlight the effect of genetic predisposition by noting the significant differences in onset age and multiple primary cancers between esophageal squamous cell carcinoma (ESCC) cases with or without a positive family history of the cancer.
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Generation and characterization of Lhx9-GFPCreER(T2) knock-in mouse line.
Genesis
PUBLISHED: 08-12-2014
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LHX9 is a LIM-homeodomain transcription factor essential for the development of gonads, spinal cord interneurons, and thalamic neurons to name a few. We recently reported the expression of LHX9 in retinal amacrine cells during development. In this study, we generated an Lhx9-GFPCreER(T) (2) (GCE) knock-in mouse line by knocking-in a GCE cassette at the Lhx9 locus, thus inactivating endogenous Lhx9. Lhx9(GCE) (/+) mice were viable, fertile, and displayed no overt phenotypical characteristics. Lhx9(GCE) (/) (GCE) mice were all phenotypically female, smaller in size, viable, but infertile. The specificity and efficacy of the Lhx9-GCE mouse line was verified by crossing it to a Rosa26-tdTomato reporter mouse line, which reveals the Cre recombinase activities in retinal amacrine cells, developing limbs, testis, hippocampal neurons, thalamic neurons, and cerebellar neurons. Taken together, the Lhx9-GCE mouse line could serve as a beneficial tool for lineage tracing and gene manipulation experiments. genesis
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Mechanical, degradation and cytocompatibility properties of magnesium coated phosphate glass fibre reinforced polycaprolactone composites.
J Biomater Appl
PUBLISHED: 07-15-2014
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Retention of mechanical properties of phosphate glass fibre reinforced degradable polyesters such as polycaprolactone and polylactic acid in aqueous media has been shown to be strongly influenced by the integrity of the fibre/polymer interface. A previous study utilising 'single fibre' fragmentation tests found that coating with magnesium improved the fibre and matrix interfacial shear strength. Therefore, the aim of this study was to investigate the effects of a magnesium coating on the manufacture and characterisation of a random chopped fibre reinforced polycaprolactone composite. Short chopped strand non-woven phosphate glass fibre mats were sputter coated with degradable magnesium to manufacture phosphate glass fibre/polycaprolactone composites. The degradation behaviour (water uptake, mass loss and pH change of the media) of these polycaprolactone composites as well as of pure polycaprolactone was investigated in phosphate buffered saline. The Mg coated fibre reinforced composites revealed less water uptake and mass loss during degradation compared to the non-coated composites. The cations released were also explored and a lower ion release profile for all three cations investigated (namely Na(+), Mg(2+) and Ca(2+)) was seen for the Mg coated composite samples. An increase of 17% in tensile strength and 47% in tensile modulus was obtained for the Mg coated composite samples. Both flexural and tensile properties were investigated and a higher retention of mechanical properties was obtained for the Mg coated fibre reinforced composite samples up to 10 days immersion in PBS. Cytocompatibility study showed both composite samples (coated and non-coated) had good cytocompatibility with human osteosarcoma cell line.
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Equivalence theorem for the spectral density of light waves on weak scattering.
Opt Lett
PUBLISHED: 07-01-2014
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The Equivalence theorem for the spectral density of light waves on weak scattering is discussed. It is shown that when a spatially coherent plane light wave is scattered from two entirely different media, the far-zone spectral density may have identical distribution provided the low-frequency antidiagonal spatial Fourier components of the correlation function of the media are the same. An example of light waves on scattering from a Gaussian Schell model medium is discussed, and the condition on which two different media may produce identical spectral densities is presented.
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Disruption of microRNA-21 by TALEN leads to diminished cell transformation and increased expression of cell-environment interaction genes.
Cancer Lett.
PUBLISHED: 06-26-2014
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MicroRNA-21 is dysregulated in many cancers and fibrotic diseases. Since miR-21 suppresses several tumor suppressor and anti-apoptotic genes, it is considered a cancer therapeutic target. Antisense oligonucleotides are commonly used to inhibit a miRNA; however, blocking miRNA function via an antagomir is temporary, often only achieves a partial knock-down, and may be complicated by off-target effects. Here, we used transcription activator-like effector nucleases (TALENs) to disrupt miR-21 in cancerous cells. Individual deletion clones were screened and isolated without drug selection. Sequencing and quantitative RT-PCR identified clones with no miR-21 expression. The loss of miR-21 led to subtle but global increases of mRNAs containing miR-21 target sequences. Cells without miR-21 became more sensitive to cisplatin and less transformed in culture and in mouse xenografts. In addition to the increase of PDCD4 and PTEN protein, mRNAs for COL4A1, JAG1, SERPINB5/Maspin, SMAD7, and TGFBI - all are miR-21 targets and involved in TGF? and fibrosis regulation - were significantly upregulated in miR-21 knockout cells. Gene ontology and pathway analysis suggested that cell-environment interactions involving extracellular matrix can be an important miR-21 pathogenic mechanism. The study also demonstrates the value of using TALEN-mediated microRNA gene disruption in human pathobiological studies.
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Alteration in methylation level at 11ß-hydroxysteroid dehydrogenase type 2 gene promoter in infants born to preeclamptic women.
BMC Genet.
PUBLISHED: 06-11-2014
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BackgroundPreeclampsia reduces placental expression and activity of 11ß-hydroxysteroid dehydrogenase type 2 (HSD11B2), leading to an increase in fetal glucocordicoids. The latter has been proposed to be associated with low birth weight and high risk of metabolic diseases in later life of the offspring. This investigation aims to delineate the alteration in methylation levels at CpG sites of HSD11B2 promoter.ResultsMethylation levels of HSD9-2, HSD9-3, HSD23-2 and HSD23-3 and the mean methylation level were significantly lower in preeclampsia than in normal pregnancy (P¿=¿0.002, 0.031, 0.047 and 0.001, respectively and P¿<¿0.001 in mean). The mean methylation level was significantly correlated with preeclampsia after the adjustment of birth weight, maternal age, gestational age at delivery and fetal gender (r¿=¿0.325, P¿<¿0.001).ConclusionsPreeclampsia reduced methylation level at fetal HSD11B2 promoter. A positive correlation existed between HSD11B2 promoter methylation and preeclampsia. Our findings suggest that the methyaltion status of HSD11B2 promoter is a potentially accessible biomarker for preeclampsia. However, further studies are required to address the mechanisms of thehypomethylation at HSD11B2 promoter and the significance of the hypomethylation in the development of metabolic diseases of the fetals born to preeclamptic women.
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The draft genome of the large yellow croaker reveals well-developed innate immunity.
Nat Commun
PUBLISHED: 06-02-2014
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The large yellow croaker, Larimichthys crocea, is one of the most economically important marine fish species endemic to China. Its wild stocks have severely suffered from overfishing, and the aquacultured species are vulnerable to various marine pathogens. Here we report the creation of a draft genome of a wild large yellow croaker using a whole-genome sequencing strategy. We estimate the genome size to be 728?Mb with 19,362 protein-coding genes. Phylogenetic analysis shows that the stickleback is most closely related to the large yellow croaker. Rapidly evolving genes under positive selection are significantly enriched in pathways related to innate immunity. We also confirm the existence of several genes and identify the expansion of gene families that are important for innate immunity. Our results may reflect a well-developed innate immune system in the large yellow croaker, which could aid in the development of wild resource preservation and mariculture strategies.
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Leber's hereditary optic neuropathy caused by the homoplasmic ND1 m.3635G>A mutation in nine Han Chinese families.
Mitochondrion
PUBLISHED: 05-30-2014
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In this report, we investigated the molecular mechanism underlying Leber's hereditary optic neuropathy (LHON)-associated mitochondrial m.3635G>A (p.S110N, ND1) mutation. A mutational screening of ND1 gene in a cohort of 1070 Han Chinese subjects LHON identified the m.3635G>A mutation in nine Chinese families with suggestively maternally transmitted LHON. Thirty-eight (22 males/16 females) of 162 matrilineal relatives in these families exhibited the variable severity and age-at-onset of optic neuropathy. Molecular analysis of their mitochondrial genomes identified the homoplasmic m.3635G>A mutation and distinct sets of polymorphisms belonging to the Asian haplogroups G2a1, R11a, D4, R11a, M7b2, G1a, F1a1, B4, and N9a3, respectively. Using cybrids constructed by transferring mitochondria from lymphoblastoid cell lines derived from one Chinese family into mtDNA-less (?(0)) cells, we showed ~27% decrease in the activity of NADH:ubiquinone oxidoreductase (complex I) in mutant cybrids carrying the m.3635G>A mutation, compared with control cybrids. The respiratory deficiency caused by the m.3635G>A mutation results in decreased efficiency of mitochondrial ATP synthesis. These mitochondrial dysfunctions caused an increase in the production of reactive oxygen species in the mutant cybrids. The data provide the direct evidence for the m.3635G>A mutation leading to LHON. Our findings may provide new insights into the understanding of pathophysiology of LHON.
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[The analysis of mitochondrial DNA haplogroups and variants for Leber's hereditary optic neuropathy in Chinese families carrying the m.14484T >C mutation].
Yi Chuan
PUBLISHED: 05-22-2014
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The m.14484T>C mutation in mitochondrial ND6 gene (MT-ND6) is a primary mutation underlying the development of Leber's hereditary optic neuropathy (LHON) , but by itself not enough to cause visual loss. To explore the role of mitochondrial haplogroups on the expression of LHON for the people carrying the m.14484T>C mutation, we performed systematic and extended mutational screening of MT-ND6 gene in a cohort of 1177 Han Chinese patients with LHON. A total of 67 affected subjects carried the homoplasmic m.14484T>C mutation, accounting for 5.7% of this LHON population. The penetrances of optic neuropathy among 51 pedigrees carrying the m.14484T>C mutation ranged from 5.6% to 100.0%, with the average of 21.5%. The sequence analysis of entire mitochondrial genomes of 51 probands exhibited distinct sets of polymorphisms belonging to 18 Eastern Asian haplogroups. The frequencies of haplogroup A and haplogroup F were sig-nificantly less in the LHON mtDNA samples than those in 106 Chinese controls. On the other hand, the haplogroup M10a accounted for 9.8% of the patient's mtDNA samples but was absent in 106 Chinese controls. Strikingly, the average pene-trance (46.13%) of optic neuropathy for the pedigrees carrying mitochondrial haplogroup M10a was higher than those car-rying other mtDNA haplogroups. These observations indicated that mitochondrial haplogroup M10a may increase the risk of visual loss.
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Metabolites from Aspergillus versicolor, an endolichenic fungus from the lichen Lobaria retigera.
Drug Discov Ther
PUBLISHED: 05-13-2014
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Three new anthraquinone derivatives (1-3) and one new artifact (4) were isolated, along with six known anthraquinone derivatives (5-10) and three xanthones (11-13), from a culture of an endolichenic fungus, Aspergillus versicolor, that was isolated from the lichen Lobaria retigera. The structures of these substances were determined on the basis of 1D and 2D (COSY, HMQC, and HMBC) NMR and MS analyses. The substances 1-4 were also tested for their cytotoxic activity.
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ATM-p53 pathway causes G2/M arrest, but represses apoptosis in pseudolaric acid B-treated HeLa cells.
Arch. Biochem. Biophys.
PUBLISHED: 05-11-2014
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Pseudolaric acid B (PAB) is a diterpene acid, isolated from the root and trunk bark of Pseudolarix kaempferi Gordon (Pinaceae). Previous studies demonstrated that PAB induced G2/M arrest and apoptosis in several cancer cell lines, but the relationship between G2/M arrest and apoptosis is still unclear. We examined the relevant signaling pathways for human cervical carcinoma HeLa cells treated with 1 ?M PAB. Intriguingly, we found that activation of ATM-p53 signaling pathway by the treatment with 1 ?M PAB played a protective role for the subsequent apoptosis. Although the treatment with 1 ?M PAB up-regulated the expression of cyclin B1 and p-Histone 3 (mitotic markers) at 12 h, the expression decreased at 24 and 36 h along with the up-down expression of mitotic markers. The expressions of p-ATM and p-p53 that were involved in G2/M arrest increased at 12h after treatment with PAB. However, a prolonged treatment with PAB (longer than 24 h) caused cell apoptosis. When the cells were arrested in G1 or S phase by the treatment with serum starvation, cytosine ?-D-arabinofuranoside (Ara-C) or hydroxyurea (Hu), the apoptotic ratio induced by PAB decreased.
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Magnesium coated phosphate glass fibers for unidirectional reinforcement of polycaprolactone composites.
J. Biomed. Mater. Res. Part B Appl. Biomater.
PUBLISHED: 05-08-2014
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Bioresorbable composites have shown much potential for bone repair applications, as they have the ability to degrade completely over time and their degradation and mechanical properties can be tailored to suit the end application. In this study, phosphate glass fiber (from the system 45% P2 O5 ?16% CaO?24% MgO?11% Na2 O?4% Fe2 O3 (given in mol%)) were used to reinforce polycaprolactone (PCL) with approximately 20% fiber volume fraction. The glass fiber surfaces were coated with magnesium (Mg) through magnetron sputtering to improve the fiber-matrix interfacial properties. The Mg coating provided a rough fiber surface (roughness (Ra) of about 44nm). Both noncoated and Mg-coated fiber-reinforced composites were assessed. The water uptake and mass loss properties for the composites were assessed in phosphate-buffered saline (PBS) at 37°C for up to 28 days, and ion release profiles were also investigated in both water and PBS media. Inhibition of media influx was observed for the Mg-coated composites. The composite mechanical properties were characterized on the basis of both tensile and flexural tests and their retention in PBS media at 37°C was also investigated. A higher retention of the mechanical properties was observed for the Mg-coated composites over the 28 days degradation period. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014.
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Roles of NF?B-miR-29s-MMP-2 circuitry in experimental choroidal neovascularization.
J Neuroinflammation
PUBLISHED: 05-01-2014
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Previous reports have indicated that matrix metallopeptidase-2 (MMP-2) regulates angiogenic processes, which are involved in choroidal neovascularization (CNV). However, the regulation of MMP-2 in CNV has not been well-characterized. To gain more information about the regulation of MMP-2 in CNV, we analyzed the circuitry associated with MMP-2 regulation in a CNV model and in cell cultures, focusing on NF?B and the microRNA-29 family (miR-29s).
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Adverse childhood experiences are associated with detrimental hemodynamics and elevated circulating endothelin-1 in adolescents and young adults.
Hypertension
PUBLISHED: 04-28-2014
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Growing evidence suggests that adverse childhood experiences (ACEs) increase the risks for coronary heart disease and hypertension in mid and late adulthood. We previously reported that early life stress induces a hyperreactive endothelin-dependent cardiovascular phenotype in a rat model. In the present study, we evaluated whether exposure to ACEs is associated with greater peripheral resistance, arterial stiffness, blood pressure, or elevated circulating endothelin-1 levels in humans. In 221 healthy adolescents and young adults (mean age, 21 years; range, 13-29 years), we found a graded association of ACE exposure with plasma endothelin-1 levels, of which on average 18% and 24% were higher in participants with 1 ACE and ?2 ACEs, respectively, compared with those with no ACEs (P=0.001). Participants with moderate/severe exposure to ACEs (?2 ACEs) had significantly higher total peripheral resistance index (+12%), diastolic blood pressure (+5%), and pulse wave velocity (+9%) compared with those who were not exposed. These associations were independent of age, race, sex, body mass index, and childhood socioeconomic status. Our results indicate that early life stress promotes cardiovascular disease risk, specifically detrimental vascular and cardiac function, detectable in young adulthood.
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Multivariate qualitative analysis of banned additives in food safety using surface enhanced Raman scattering spectroscopy.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 04-21-2014
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A novel strategy which combines iteratively cubic spline fitting baseline correction method with discriminant partial least squares qualitative analysis is employed to analyze the surface enhanced Raman scattering (SERS) spectroscopy of banned food additives, such as Sudan I dye and Rhodamine B in food, Malachite green residues in aquaculture fish. Multivariate qualitative analysis methods, using the combination of spectra preprocessing iteratively cubic spline fitting (ICSF) baseline correction with principal component analysis (PCA) and discriminant partial least squares (DPLS) classification respectively, are applied to investigate the effectiveness of SERS spectroscopy for predicting the class assignments of unknown banned food additives. PCA cannot be used to predict the class assignments of unknown samples. However, the DPLS classification can discriminate the class assignment of unknown banned additives using the information of differences in relative intensities. The results demonstrate that SERS spectroscopy combined with ICSF baseline correction method and exploratory analysis methodology DPLS classification can be potentially used for distinguishing the banned food additives in field of food safety.
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DNA methylation of the LY86 gene is associated with obesity, insulin resistance, and inflammation.
Twin Res Hum Genet
PUBLISHED: 04-15-2014
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Previous genome-wide association studies (GWAS) have identified a large number of genetic variants for obesity and its related traits, representing a group of potential key genes in the etiology of obesity. Emerging evidence suggests that epigenetics may play an important role in obesity. It has not been explored whether the GWAS-identified loci contribute to obesity through epigenetics (e.g., DNA (deoxyribonucleic acid) methylation) in addition to genetics.
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Oligochitosan stimulated phagocytic activity of macrophages from blunt snout bream (Megalobrama amblycephala) associated with respiratory burst coupled with nitric oxide production.
Dev. Comp. Immunol.
PUBLISHED: 04-08-2014
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The immunostimulating effects of oligochitosan have been proven in several fish, however, the mechanisms underlying the stimulation are not characterized. In the present study, the effects of oligochitosan were investigated using macrophages isolated from blunt snout bream (Megalobrama amblycephala). The results showed that the phagocytic activity of the macrophages was enhanced by the addition of oligochitosan in vitro and in vivo. The two of the most important antimicrobial pathways of macrophages, NADPH oxidase and iNOS pathways were included for further studies. The amounts of superoxide anion and the mRNAs of the five subunits of NADPH oxidase genes were significantly enhanced in the oligochitosan-treated macrophages and macrophages isolated from fish fed with feed containing oligochitosan. In addition, the NO production, iNOS activity and iNOS gene expression were all significantly increased in the presence of oligochitosan. Furthermore, the mRNA levels of the TNF-? and IL-1? were also significantly increased in the macrophages derived from fish fed with oligochitosan. In conclusion, the stimulation effects of oligochitosan on the phagocytic activity of the fish macrophages were associated with respiratory burst coupled with nitric oxide production.
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Characterization of a new 1,3-1,4-?-glucanase gene from Bacillus tequilensis CGX5-1.
Appl. Biochem. Biotechnol.
PUBLISHED: 04-02-2014
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1,3-1,4-?-Glucanase received great interest due to its application in brewing and feed industries. Application of 1,3-1,4-?-glucanase in brewing industry helps make up for the defect that plant-derived ?-glucanases are heat-sensitive. A new strain, CGX5-1, exhibited remarkable 1,3-1,4-?-glucanase, was isolated from Asian giant hornet nest and identified Bacillus tequilensis. Moreover, a new 1,3-1,4-?-glucanase gene from B. tequilensis was cloned and measured to be 720 bp encoding 239 amino acids, with a predicted molecular weight of 26.9 kDa. After expressed in Escherichia coli BL21, active recombinant enzyme of 24 kDa was detected in the supernatant of cell culture, with the activity of 2,978.2 U/mL. The new enzyme was stable in the pH 5.0-7.5 with the highest activity measured at pH 6.0. Moreover, it is thermostable within 45 to 60 °C. The property of the new recombinant enzyme makes this enzyme a broad prospect in brewing industry. Moreover, this is the first report on 1,3-1,4-?-glucanase produced by B. tequilensis.
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Whole-exome and targeted gene sequencing of gallbladder carcinoma identifies recurrent mutations in the ErbB pathway.
Nat. Genet.
PUBLISHED: 03-23-2014
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Individuals with gallbladder carcinoma (GBC), the most aggressive malignancy of the biliary tract, have a poor prognosis. Here we report the identification of somatic mutations for GBC in 57 tumor-normal pairs through a combination of exome sequencing and ultra-deep sequencing of cancer-related genes. The mutation pattern is defined by a dominant prevalence of C>T mutations at TCN sites. Genes with a significant frequency (false discovery rate (FDR)<0.05) of non-silent mutations include TP53 (47.1%), KRAS (7.8%) and ERBB3 (11.8%). Moreover, ErbB signaling (including EGFR, ERBB2, ERBB3, ERBB4 and their downstream genes) is the most extensively mutated pathway, affecting 36.8% (21/57) of the GBC samples. Multivariate analyses further show that cases with ErbB pathway mutations have a worse outcome (P=0.001). These findings provide insight into the somatic mutational landscape in GBC and highlight the key role of the ErbB signaling pathway in GBC pathogenesis.
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Vortex-assisted magnetic dispersive solid-phase microextraction for rapid screening and recognition of dicofol residues in tea products.
Food Chem
PUBLISHED: 03-15-2014
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A simple and rapid vortex-assisted magnetic dispersive solid-phase microextraction (VAMDSME) method coupled with gas chromatography-electronic capture detection was developed for rapid screening and selective recognition of dicofol in tea products. The magnetic molecularly imprinted microspheres (mag-MIMs) synthesised by aqueous suspension polymerisation using dichlorodiphenyltrichloroethane (DDT) as a dummy template showed high selectivity and affinity to dicofol in aqueous solution and were successfully applied as special adsorbents of VAMDSME for rapid isolation of dicofol from complex tea matrix. Good linearity was obtained in a range of 0.2-160 ng g(-1) and the limit of detection based on a signal to noise ratio of 3 was 0.05 ng g(-1). The recoveries at three spiked levels ranged from 83.6% to 94.5% with the related standard deviations (RSD) ? 5.0%. The VAMDSME-GC protocol, which took advantages of the selective adsorption of molecularly imprinted microspheres and rapid magnetic phase separation, as well as the short equilibrium time by vortex-assisted, could avoid the time-consuming procedures related to other traditional extraction methods.
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Molecular cloning and expression analysis of mannose receptor in blunt snout bream (Megalobrama amblycephala).
Mol. Biol. Rep.
PUBLISHED: 03-10-2014
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Mannose receptor (MR) plays a significant role in innate immune responses to pathogens in vertebrates. Here we characterized the first teleost MR from Megalobrama amblycephala, named maMR and its expression patterns were investigated. The full-length maMR consists of 5,295 bp encoding a putative protein of 1,433 amino acids. The predicted amino acid sequences showed that maMR contained a signal peptide, a cysteine-rich domain, a single fibronectin type II domain, eight tandemly arranged C-type lectin-like domains, a transmembrane domain and a C-terminal cytoplasmic domain. Phylogenetic analysis revealed the highest similarity of maMR with Danio rerio MR predicted by computational analysis. The maMR-mRNAs were ubiquitously transcribed in different tissues, However the highest transcripts were observed in head kidney. Transcripts of maMR significantly increased at the late stages of embryo and continued to be at the high levels after hatching. The maMR transcripts were significantly increased in M. amblycephala after stimulation with killed Aeromonas hydrophila.
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Identification, expression and interaction analyses of calcium-dependent protein kinase (CPK) genes in canola (Brassica napus L.).
BMC Genomics
PUBLISHED: 03-07-2014
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Canola (Brassica napus L.) is one of the most important oil-producing crops in China and worldwide. The yield and quality of canola is frequently threatened by environmental stresses including drought, cold and high salinity. Calcium is a well-known ubiquitous intracellular secondary messenger in plants. Calcium-dependent protein kinases (CPKs) are Ser/Thr protein kinases found only in plants and some protozoans. CPKs are Ca2+ sensors that have both Ca2+ sensing function and kinase activity within a single protein and play crucial roles in plant development and responses to various environmental stresses.
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Association study of newly identified age-related macular degeneration susceptible loci SOD2, MBP, and C8orf42 in Han Chinese population.
Diagn Pathol
PUBLISHED: 02-25-2014
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A recent genome-wide association study has reported three newly identified susceptible loci (rs2842992 near the gene SOD2, rs1789110 near the gene MBP and rs722782 near the gene C8orf42) to be associated with the geographic atrophy subtype of age-related macular degeneration in European-descent population. We investigated the correlation between these variants and advanced age-related macular degeneration for the first time in a Han Chinese cohort; however, no evidence supports these previously identified loci contribute to advanced age-related macular degeneration susceptibility in Chinese population.
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Propagation characteristics of decentered annular beams through non-Kolmogorov turbulence.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 02-25-2014
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This paper studies the propagation characteristics related to higher-order moments of decentered annular beams through non-Kolmogorov turbulence. The analytical expressions for the mean-squared beam width w, the skewness parameter A, and the kurtosis parameter K are derived. The analytical expression for the non-Kolmogorov turbulence parameter T' is also derived, and the differences between two non-Kolmogorov turbulence parameters T' and T are examined. It is shown that K depends on both T and T', but w and A only depend on T. K decreases monotonically as the spectral power law exponent ? increases, but there exist a maximum of w and a minimum of A when ?=3.112. When propagation distance z is long enough, A reaches zero, i.e., the intensity distribution is perfectly symmetric about the centroid position axis. In free space, both A>0 and A<0 may appear on propagation. However, it is always A>0 or A<0 on propagation when turbulence is not weak. On the other hand, in turbulence, the maximum of K increases as the decentered parameter increases and the obscure ratio decreases. In particular, when z is long enough, the beam spot is elliptical in free space, but it becomes circular in turbulence.
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A new nanoPCR molecular assay for detection of porcine bocavirus.
J. Virol. Methods
PUBLISHED: 02-24-2014
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Nanoparticle-assisted polymerase chain reaction (nanoPCR) is a novel method for the rapid amplification of DNA and has been used for the detection of virus. For detection of porcine bocavirus (PBoV), a sensitive and specific nanoPCR assay was developed with a pair of primers that were designed based on NS1 gene sequences available in GenBank. Under the optimized conditions of the PBoV nanoPCR assay, the nanoPCR assay was 100-fold more sensitive than a conventional PCR assay. The lower detection limit of the nanoPCR assay was about 6.70×10(1) copies. The nanoPCR assay amplified the specific 482-bp fragment of the PBoV NS1 recombinant plasmid but did not produce any product with genomic DNA or cDNA of porcine parvovirus, porcine circovirus type II, porcine reproductive and respiratory syndrome virus, pseudorabies virus, classic swine fever virus, Encephalomyocarditis virus, Porcine Teschovirus or African swine fever virus plasmid. Of 65 clinical samples collected from diseased pigs, 73.8% and 86.2% were determined to be PBoV positive by PBoV conventional PCR and PBoV nanoPCR assay, respectively. Of 36 clinical samples from healthy pigs, 27.8% and 44.4% were PBoV positive by PBoV conventional PCR and PBoV nanoPCR assay, respectively. The nanoPCR assay will be useful for diagnosing PBoV and for studying its epidemiology and pathology.
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Development and evaluation of the rVP-ELISA for detection of antibodies against porcine parvovirus.
J. Virol. Methods
PUBLISHED: 02-17-2014
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The gene encoding the VP2 protein of porcine parvovirus (PPV) was expressed in an insect-baculovirus system. The recombinant (r) VP2 was similar antigenically/functionally to the native capsid protein as demonstrated by hemagglutination (HA), Western blotting using PPV positive sera. The purified rVP2 proteins were used as coating antigen to establish a rVP-ELISA method for detection of PPV positive and negative sera from pigs. The optimal operating conditions of the rVP-ELISA were: the concentration of rVP2 proteins coated on the wells was 2 ?g/mL; the diluted concentration of serum was 1: 150 and that of the enzyme-labeled antibody was 1: 6000. A total of 596 sera were detected by this assay, and the average positive rate was 87%. Compared with France LSI kit, the result showed that the coincidence rate was 96.7%. In conclusion, the rVP2-ELISA is a sensitive and specific method for detecting antibodies against PPV.
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Development of simple sequence repeat (SSR) markers of sesame (Sesamum indicum) from a genome survey.
Molecules
PUBLISHED: 02-17-2014
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Sesame (Sesamum indicum), an important oil crop, is widely grown in tropical and subtropical regions. It provides part of the daily edible oil allowance for almost half of the world's population. A limited number of co-dominant markers has been developed and applied in sesame genetic diversity and germplasm identity studies. Here we report for the first time a whole genome survey used to develop simple sequence repeat (SSR) markers and to detect the genetic diversity of sesame germplasm. From the initial assembled sesame genome, 23,438 SSRs (?5 repeats) were identified. The most common repeat motif was dinucleotide with a frequency of 84.24%, followed by 13.53% trinucleotide, 1.65% tetranucleotide, 0.3% pentanucleotide and 0.28% hexanucleotide motifs. From 1500 designed and synthesised primer pairs, 218 polymorphic SSRs were developed and used to screen 31 sesame accessions that from 12 countries. STRUCTURE and phylogenetic analyses indicated that all sesame accessions could be divided into two groups: one mainly from China and another from other countries. Cluster analysis classified Chinese major sesame varieties into three groups. These novel SSR markers are a useful tool for genetic linkage map construction, genetic diversity detection, and marker-assisted selective sesame breeding.
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Neuronal apoptosis in cerebral ischemia/reperfusion area following electrical stimulation of fastigial nucleus.
Neural Regen Res
PUBLISHED: 02-12-2014
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Previous studies have indicated that electrical stimulation of the cerebellar fastigial nucleus in rats may reduce brain infarct size, increase the expression of Ku70 in cerebral ischemia/reperfusion area, and decrease the number of apoptotic neurons. However, the anti-apoptotic mechanism of Ku70 remains unclear. In this study, fastigial nucleus stimulation was given to rats 24, 48, and 72 hours before cerebral ischemia/reperfusion injury. Results from the electrical stimulation group revealed that rats exhibited a reduction in brain infarct size, a significant increase in the expression of Ku70 in cerebral ischemia/reperfusion regions, and a decreased number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells. Double immunofluorescence staining revealed no co-localization of Ku70 with TUNEL-positive cells. However, Ku70 partly co-localized with Bax protein in the cytoplasm of rats with cerebral ischemia/reperfusion injury. These findings suggest an involvement of Ku70 with Bax in the cytoplasm of rats exposed to electrical stimulation of the cerebellar fastigial nucleus, and may thus provide an understanding into the anti-apoptotic activity of Ku70 in cerebral ischemia/reperfusion injury.
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Safety and efficacy of conbercept in neovascular age-related macular degeneration: results from a 12-month randomized phase 2 study: AURORA study.
Ophthalmology
PUBLISHED: 02-12-2014
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To assess the safety and efficacy of multiple injections of 0.5 and 2.0 mg conbercept using variable dosing regimens in patients with neovascular age-related macular degeneration (AMD).
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DNA methylation profiling in the thalamus and hippocampus of postnatal malnourished mice, including effects related to long-term potentiation.
BMC Neurosci
PUBLISHED: 02-11-2014
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DNA methylation has been viewed as the most highly characterized epigenetic mark for genome regulation and development. Postnatal brains appear to exhibit stimulus-induced methylation changes because of factors such as environment, lifestyle, and diet (nutrition). The purpose of this study was to examine how extensively the brain DNA methylome is regulated by nutrition in early life.
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Dietary sodium, adiposity, and inflammation in healthy adolescents.
Pediatrics
PUBLISHED: 02-02-2014
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To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents.
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Isolation, purification, and cultivation of primary retinal microvascular pericytes: a novel model using rats.
Microcirculation
PUBLISHED: 01-30-2014
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To isolate, purify, and cultivate primary retinal microvascular pericytes (RMPs) from rats to facilitate the study of their properties in vitro.
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Disruption of a methyltransferase gene in actinomycin G gene cluster in Streptomyces iakyrus increases the production of phenazinomycin.
FEMS Microbiol. Lett.
PUBLISHED: 01-27-2014
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Phenazinomycin is a hybrid natural product consisting of two chemical entities, a phenazine and a cyclic terpenoid. Phenazinomycin exhibits potent activity against murine tumors and adriamycin-resistant P388 leukemia cells. Streptomyces iakyrus DSM 41873 is known to produce five actinomycin G2 -G6 . In the previous study, we identified the gene cluster directing the biosynthesis of actinomycin G2 -G4 . Inactivation of acmG5' gene in the actinomycin G gene cluster in S. iakyrus completely abolished the production of actinomycin G. Metabolic profiling, chemical isolation, and structural elucidation of the resulting mutant SIA?acmG5' showed a previously unnoticed metabolite phenazinomycin in S. iakyrus. In silico analysis identified a hybrid biosynthetic gene cluster in the genome of S. iakyrus that could be responsible for the biosynthesis of phenazinomycin. It is proposed that the perturbation of actinomycin G to enhance the phenazinomycin production in the mutant may result from the lifted competition of chorismate, the common precursor of the biosynthetic pathways of these two structurally unrelated natural products.
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Mitochondrial haplotypes may modulate the phenotypic manifestation of the LHON-associated ND1 G3460A mutation in Chinese families.
J. Hum. Genet.
PUBLISHED: 01-16-2014
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To investigate the pathophysiology of Leber's hereditary optic neuropathy (LHON), a cohort of 1164 Han Chinese subjects with LHON were screened for ND1 G3460A mutation. A total of 295 subjects from 16 Han Chinese families carrying the G3460A mutation underwent a clinical and genetic evaluation and molecular analysis of mitochondrial (mt)DNA. The incidence of G3460A mutation was 1.4% in this cohort of Chinese subjects with LHON. Twenty-seven (20 males/7 females) of 109 matrilineal relatives among 10 Chinese pedigrees carrying this mutation exhibited a wide range of severity and age-at-onset in visual impairment. Penetrances of optic neuropathy ranged from 7.1% to 50%, with the average of 24.5%. The age-at-onset of 27 affected matrilineal relatives varied from 10 to 40 years, with the average of 22 years. Molecular analysis identified the homoplasmic G3460A mutation and distinct sets of variants belonging to eight haplogroups. Haplogroup M with G3460A mutation was of higher frequency than those in controls. The penetrances of visual loss in families carrying mitochondrial DNA haplogroups A, B and M were higher than those in other families. Furthermore, haplogroup-specific variants tRNA(Ser(AGY)) A12223G, tRNA(Thr) G15927A and tRNA(Glu) A14693G may enhance the penetrance of visual loss in these families. The G3460A mutation occurred through recurrent origins and founder events in Chinese population. Mitochondrial modifiers may modulate the penetrance and expressivity of optic neuropathy among Chinese pedigrees carrying the G3460A mutation. Thus, our findings may provide new insights into the understanding of pathophysiology and valuable information on the management of LHON.
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Frequency and spectrum of mitochondrial ND6 mutations in 1218 Han Chinese subjects with Leber's hereditary optic neuropathy.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 01-09-2014
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To investigate the molecular pathogenesis of Leber's hereditary optic neuropathy (LHON) in Chinese families.
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Angiopoietin-like 4 stimulates STAT3-mediated iNOS expression and enhances angiogenesis to accelerate wound healing in diabetic mice.
Mol. Ther.
PUBLISHED: 01-06-2014
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Impaired wound healing is a major source of morbidity in diabetic patients. Poor outcome has, in part, been related to increased inflammation, poor angiogenesis, and deficiencies in extracellular matrix components. Despite the enormous impact of these chronic wounds, effective therapies are lacking. Here, we showed that the topical application of recombinant matricellular protein angiopoietin-like 4 (ANGPTL4) accelerated wound reepithelialization in diabetic mice, in part, by improving angiogenesis. ANGPTL4 expression is markedly elevated upon normal wound injury. In contrast, ANGPTL4 expression remains low throughout the healing period in diabetic wounds. Exogenous ANGPTL4 modulated several regulatory networks involved in cell migration, angiogenesis, and inflammation, as evidenced by an altered gene expression signature. ANGPTL4 influenced the expression profile of endothelial-specific CD31 in diabetic wounds, returning its profile to that observed in wild-type wounds. We showed ANGPTL4-induced nitric oxide production through an integrin/JAK/STAT3-mediated upregulation of inducible nitric oxide synthase (iNOS) expression in wound epithelia, thus revealing a hitherto unknown mechanism by which ANGPTL4 regulated angiogenesis via keratinocyte-to-endothelial-cell communication. These data show that the replacement of ANGPTL4 may be an effective adjunctive or new therapeutic avenue for treating poor healing wounds. The present finding also confirms that therapeutic angiogenesis remains an attractive treatment modality for diabetic wound healing.
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Systemic Epstein-Barr virus positive T-cell lymphoproliferative disease of childhood with hemophagocytic syndrome.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Epstein-Barr virus (EBV) associated lymphoproliferative disease (LPD) are commonly derived from B-cells, however, it is becoming more and more apparently that EBV can also infect T-lymphocytes. Systemic EBV positive T-cell LPD of childhood is rare and characterized by an extremely aggressive course and poor prognosis. Here, we report a 22-year-old female of systemic EBV positive TLPD with acute EBV infection and review the clinical features of this disorder. A 22-year-old previously healthy female without immunocompromised status presented with persisting coach and fever resistant to conventional therapies. Physical examination showed hemorrhage and hepatosplenomegaly. Laboratory examinations revealed severe pancytopenia, disseminated intra-vascular coagulopathy (DIC), and anti-EBV-IgM positivity. Peripheral blood smears and bone marrow investigation identified a number of atypical lymphocytes. Flow cytometry (FCM) did not show any significant evidence of leukemia or lymphoma. The lymph node biopsy showed apparent infiltration of lymphocytes, which expressed CD2+, CD3+, CD7+ and TIA1+. There was no CD20+ or CD56+ cells. EBV early RNA (EBER) was positive. Cytogenetic analysis showed a normal karyotype. T-cell receptor (TCR) gene rearrangement revealed a polyclonal pattern. The patient received prednisolone and IVIG therapy with a transient good condition, and then died of multiorgan failure one week after diagnosis.
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Identifying genetic variants for heart rate variability in the acetylcholine pathway.
PLoS ONE
PUBLISHED: 01-01-2014
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Heart rate variability is an important risk factor for cardiovascular disease and all-cause mortality. The acetylcholine pathway plays a key role in explaining heart rate variability in humans. We assessed whether 443 genotyped and imputed common genetic variants in eight key genes (CHAT, SLC18A3, SLC5A7, CHRNB4, CHRNA3, CHRNA, CHRM2 and ACHE) of the acetylcholine pathway were associated with variation in an established measure of heart rate variability reflecting parasympathetic control of the heart rhythm, the root mean square of successive differences (RMSSD) of normal RR intervals. The association was studied in a two stage design in individuals of European descent. First, analyses were performed in a discovery sample of four cohorts (n?=?3429, discovery stage). Second, findings were replicated in three independent cohorts (n?=?3311, replication stage), and finally the two stages were combined in a meta-analysis (n?=?6740). RMSSD data were obtained under resting conditions. After correction for multiple testing, none of the SNPs showed an association with RMSSD. In conclusion, no common genetic variants for heart rate variability were identified in the largest and most comprehensive candidate gene study on the acetylcholine pathway to date. Future gene finding efforts for RMSSD may want to focus on hypothesis free approaches such as the genome-wide association study.
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Precise gene modification mediated by TALEN and single-stranded oligodeoxynucleotides in human cells.
PLoS ONE
PUBLISHED: 01-01-2014
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The development of human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) facilitates in vitro studies of human disease mechanisms, speeds up the process of drug screening, and raises the feasibility of using cell replacement therapy in clinics. However, the study of genotype-phenotype relationships in ESCs or iPSCs is hampered by the low efficiency of site-specific gene editing. Transcription activator-like effector nucleases (TALENs) spurred interest due to the ease of assembly, high efficiency and faithful gene targeting. In this study, we optimized the TALEN design to maximize its genomic cutting efficiency. We showed that using optimized TALENs in conjunction with single-strand oligodeoxynucleotide (ssODN) allowed efficient gene editing in human cells. Gene mutations and gene deletions for up to 7.8 kb can be accomplished at high efficiencies. We established human tumor cell lines and H9 ESC lines with homozygous deletion of the microRNA-21 (miR-21) gene and miR-9-2 gene. These cell lines provide a robust platform to dissect the roles these genes play during cell differentiation and tumorigenesis. We also observed that the endogenous homologous chromosome can serve as a donor template for gene editing. Overall, our studies demonstrate the versatility of using ssODN and TALEN to establish genetically modified cells for research and therapeutic application.
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Accurate and economical detection of ALK positive lung adenocarcinoma with semiquantitative immunohistochemical screening.
PLoS ONE
PUBLISHED: 01-01-2014
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Right detection of anaplastic lymphoma kinase (ALK) gene rearrangement is pivotal to selection of patients with lung adenocarcinoma for ALK-targeted therapy. We explored the potential of combination of immunohistochemistry (IHC) screening and fluorescence in situ hybridization (FISH) as an affordable practice. We analyzed 410 unselected lung adenocarcinomas by ALK IHC (D5F3 clone) and FISH. Some equivocal cases were further analyzed by RT-PCR. The EGFR mutation was detected by pyrosequencing assay. In total 368 cases which got all IHC, FISH, EGFR mutation results were eligible for analysis. Cases were evaluated as IHC score 3+ (n = 26), score 2+ (n = 9), score 1+ (n = 51), and score 0 (n = 282), respectively. 23 of 26 IHC 3+ and 5 of 9 IHC 2+ cases were FISH positive, whereas 3 of 26 IHC 3+, 4 of 9 IHC 2+ and all 333 IHC 1+/0 cases were FISH negative. If considering FISH as the standard, the sensitivity and specificity of ALK IHC 3+/2+ as ALK positive were 100% and 97.9%, respectively. Three IHC 3+ cases reported as FISH "negative" were actually ALK positive confirmed by ALK RT-PCR or re-detected. Based on the final classify, ALK IHC 3+/2+ was 100% sensitive and 98.8% specific. However, FISH was 90.3% sensitive and 100% specific. IHC 2+ was regarded as equivocal and need to be confirmed by FISH or RT-PCR. In the 368 cases, 8.4% cases had ALK positive, 52.2% cases had EGFR mutation, and only one case had a coexisting. Manually semiquantitative ALK IHC (primary antibody D5F3 coupled with secondary DAKO Envision system) used as the initial screening combined with auxiliary FISH confirmation is a reliable, economical approach to identify ALK positive lung adenocarcinoma. The IHC can find some ALK positive cases which would be missed by FISH only.
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A genome-wide association study identifies a locus on TERT for mean telomere length in Han Chinese.
PLoS ONE
PUBLISHED: 01-01-2014
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Leukocyte telomere length (LTL) is a predictor of aging and a number of age-related diseases. We performed genome-wide association studies of mean LTL in 2632 individuals,with a two-stage replication in 3917 individuals from Chinese populations. To further validate our findings, we get the results of 696 samples from a cohort of European ancestry. We identified two loci associated with LTL that map in telomerase reverse transcriptase (TERT; rs2736100, P?=?1.93×10(-5)) on chromosome 5p15.33 and near keratin 80 (KRT80; rs17653722, P?=?6.96×10(-6)) on 12q13.13. In Chinese population each C allele of rs2736100 and T allele of rs17653722 was associated with a longer mean telomere length of 0.026 and 0.059 T/S, respectively, equivalent to about 3 and 7 years of average age-related telomere attrition. Our findings provide new insights into telomere regulatory mechanism and even pathogenesis of age-related diseases.
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Alveolar adenoma resected by thoracoscopic surgery.
Ann Thorac Cardiovasc Surg
PUBLISHED: 11-08-2013
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Alveolar adenoma, a rare benign pulmonary neoplasm, usually presents as asymptomatic. Since first described in 1986, no more than 35 cases have been reported in the English medical literature. Here we report a case of 48-year-old woman who suffered from this tumor, the patient is doing well 4 years after thoracoscopic lobectomy.
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Enhanced atherosclerosis in TIPE2-deficient mice is associated with increased macrophage responses to oxidized low-density lipoprotein.
J. Immunol.
PUBLISHED: 09-30-2013
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Atherosclerosis has been widely recognized as an inflammatory disease of the arterial wall in which macrophages play a major role. Yet, how macrophage-mediated pathology is regulated during atherosclerosis is poorly understood. TNF-?-induced protein 8-like 2 (TIPE2, also known as TNFAIP8L2) is highly expressed in resting macrophages and can negatively regulate inflammation through inhibiting immune receptor signaling. We report in this article that TIPE2 plays a crucial atheroprotective role likely by regulating macrophage responses to oxidized low-density lipoprotein (ox-LDL). TIPE2-deficient macrophages treated with ox-LDL produced more oxidative stress and proinflammatory cytokines, and exhibited heightened activation of the JNK, NF-?B, and p38 signaling pathways. As a consequence, TIPE2 deficiency in bone marrow-derived cells exacerbated atherosclerosis development in Ldlr(-/-) mice fed a high-fat diet. Importantly, ox-LDL markedly downregulated TIPE2 mRNA and protein levels in macrophages, suggesting that ox-LDL mediates atherosclerosis by TIPE2 inhibition. These results indicate that TIPE2 is a new inhibitor of atherosclerosis and a potential drug target for treating the disease.
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Molecular cloning and expression analysis of mannose receptor C type 1 in grass carp (Ctenopharyngodon idella).
Dev. Comp. Immunol.
PUBLISHED: 09-17-2013
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Mannose receptor C type 1 (MRC1) is a pattern-recognition receptor (PRR) which plays a significant role in immune responses. Much work on MRC1 has been done in mammals and birds while little in fish. In this study, we cloned and characterized MRC1 in grass carp (gcMR). The full-length gcMR contained 5291bp encoding a putative protein of 1432 amino acids. The predicted amino acid sequences showed that gcMR contained a signal peptide, a cysteine-rich (CR) domain, a fibronectin type II (FN II) domain, eight C-type lectin-like domains (CTLDs), a transmembrane domain and a short cytoplasmic domain. gcMR were constitutively expressed in different organs with the higher expression in spleen and head kidney. During embryonic development, gcMR transcript levels were highest at cleavage stage. The up-regulation expression of gcMR, IL-1? and TNF-? in liver, spleen, head kidney and intestine after Aeromonas hydrophila infection indicating it involved in innate immune regulation during bacterial infections.
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Associations of neonatal lead, cadmium, chromium and nickel co-exposure with DNA oxidative damage in an electronic waste recycling town.
Sci. Total Environ.
PUBLISHED: 09-14-2013
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This study aimed to evaluate the effects of toxic heavy metal co-exposure on DNA oxidative damage in neonates from a primitive e-waste recycling region, Guiyu town, China.
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Graphene oxide and reduced graphene oxide as novel stationary phases via electrostatic assembly for open-tubular capillary electrochromatography.
Electrophoresis
PUBLISHED: 08-27-2013
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We present here the application of graphene oxide (GO) and reduced graphene oxide (GOOH) sheet as novel stationary phases for open-tubular CEC (OTCEC) separation based on electrostatic assembly. The inner walls of a bare capillary column was first modified by ionic assembly of poly (diallyldimethylammonium chloride) (PDDA), and then negatively charged GO or GOOH was easily assembled on a positively charged interior walls of the capillary by electrostatic force. Scanning Electron Microscope images showed that GO and GOOH can still maintain sheet-layer-like structure when coated onto the capillary via electrostatic assembly. The chromatographic properties of the GO and GOOH coated columns were evaluated via OTCEC separations of various kinds of analytes, including three acid nitrophenol isomers, three basic nitroaniline isomers, and four neutral PAHs. Efficient separations of all the analytes were achieved with optimized buffer pH and organic additive. The reproducibility and stability of the GO or GOOH coated columns were investigated. Our results indicate the capability of application GO or GOOH sheet in OTCEC separation, which can be coated on the inner wall of fused-silica capillary via electrostatic assembly.
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A nonribosomal peptide synthase containing a stand-alone condensation domain is essential for phytotoxin zeamine biosynthesis.
Mol. Plant Microbe Interact.
PUBLISHED: 07-26-2013
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Dickeya zeae is the causal agent of rice foot rot and maize stalk rot diseases, which could cause severe economic losses. The pathogen is known to produce two phytotoxins known as zeamine and zeamine II which are also potent antibiotics against both gram-positive and gram-negative bacteria pathogens. Zeamine II is a long-chain aminated polyketide and zeamine shares the same polyketide structure as zeamine II, with an extra valine derivative moiety conjugated to the primary amino group of zeamine II. In this study, we have identified a gene designated as zmsK encoding a putative nonribosomal peptide synthase (NRPS) by screening of the transposon mutants defective in zeamine production. Different from most known NRPS enzymes, which are commonly multidomain proteins, ZmsK contains only a condensation domain. High-performance liquid chromatography and mass spectrometry analyses showed that the ZmsK deletion mutant produced only zeamine II but not zeamine, suggesting that ZmsK catalyzes the amide bond formation by using zeamine II as a substrate to generate zeamine. We also present evidence that a partially conserved catalytic motif within the condensation domain is critical for zeamine production. Furthermore, we show that deletion of zmsK substantially decreased the total antimicrobial activity and virulence of D. zeae. Our findings provide a new insight into the biosynthesis pathway of zeamines and the virulence mechanisms of the bacterial pathogen D. zeae.
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Cancer-associated fibroblasts enhance the migration ability of ovarian cancer cells by increasing EZH2 expression.
Int. J. Mol. Med.
PUBLISHED: 07-25-2013
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The tumor microenvironment is thought to affect malignant transformation and tumor progression. The histone methyltransferase, enhancer of zeste homologue 2 (EZH2), has recently been suggested to play a critical role in the tumorigenesis of several types of human cancer. The aim of this study was to investigate the effects of cancer-associated fibroblasts (CAFs) on the expression of EZH2 and the migration ability of ovarian cancer cells, in order to explore the link between the tumor microenvironment and epigenetic regulation. The ovarian cancer cell lines, A2780, SKOV3 and ES2, were indirectly co-cultured with primary ovarian CAFs or normal fibroblasts (NFs). The migration ability of the ovarian cancer cells was determined by Transwell migration assay. The expression levels of EZH2 were assessed by quantitative reverse transcription PCR (qRT-PCR) and western blot analysis. The A2780-shEZH2 cells (A2780 cells transfected with shRNA targeting EZH2) were indirectly co-cultured with CAFs or NFs, and the changes in the expression levels of EZH2 and the migration ability of the cells were detected. The migration ability of the A2780, SKOV3 and ES2 cells co-cultured with CAFs was significantly enhanced (P<0.05) compared with the NF group and the cells cultured alone. The expression of EZH2 in the A2780, SKOV3 and ES2 cells was significantly increased following co-culture with CAFs (P<0.001) compared with the cells cultured alone but not those cultured with NFs. The migration ability of the A2780-shEZH2 cells was not significantly increased following co-culture with CAFs (P>0.05). Our data indicate that CAFs enhance the migration ability of ovarian cancer cells partly by increasing EZH2 expression.
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Alkaline pretreatment for enhancement of biogas production from banana stem and swine manure by anaerobic codigestion.
Bioresour. Technol.
PUBLISHED: 07-21-2013
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The objective of this research was to propose and investigate the availability of digested banana stem (BS) to produce biogas. Squeezed BS with less moisture content was used for biogas production through a combination of NaOH pretreatment, solid-state fermentation, and codigestion technologies. NaOH doses were optimized according to biogas fermentation performance, and the best dose was 6% (by weight) based on the total solid (TS) of BS. Under this condition, the lignin, cellulose, and hemicellulose contents decreased from 18.36%, 32.36% and 14.6% to 17.10%, 30.07%, and 10.65%, respectively, after pretreatment. After biogas digestion, TS and volatile solid (VS) reductions of the codigestion were 48.5% and 70.4%, respectively, and the biogas and methane yields based on VS loading were 357.9 and 232.4 mL/g, which were 12.1% and 21.4%, respectively, higher than the control. Results indicated that the proposed process could be an effective method for using BS to produce biogas.
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The THO ribonucleoprotein complex is required for stem cell homeostasis in the adult mouse small intestine.
Mol. Cell. Biol.
PUBLISHED: 07-01-2013
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RNA processing and transport are mediated by cotranscriptionally assembled ribonucleoprotein (RNP) complexes. RNPs have been postulated to help specify coordinated gene expression, but the requirements for specific RNP complexes in mammalian development and tissue homeostasis have not been extensively evaluated. THO is an evolutionarily conserved RNP complex that links transcription with nuclear export. THO is not essential for Saccharomyces cerevisiae viability, but it is essential for early mouse embryonic development. Embryonic lethality has limited the characterization of THO requirements in adult tissues. To overcome this limitation, a mouse model has been generated that allows widespread inducible deletion of Thoc1, which encodes an essential protein subunit of THO. Widespread Thoc1 deletion disrupts homeostasis within the small intestine but does not have detectable effects in other epithelial tissues such as the related mucosa of the large intestine. Thoc1 loss compromises the proliferation and lineage-generating capacity of small intestinal stem cells, disrupting the supply of differentiated cells in this rapidly renewing tissue. These findings demonstrate that the effects of THO deficiency in the adult mouse are tissue and cell type dependent.
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Experimental method for characterizing CVOC removal from fractured clays during boiling.
J. Contam. Hydrol.
PUBLISHED: 06-14-2013
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Conventional remediation methods that rely on contact with contaminants can be ineffective in fractured media, but thermal methods of remediation involving CVOC stripping at boiling temperature show promise. However, limited experimental data are available to characterize thermal remediation because of challenges associated with high temperature. This research reports an experimental method using uniformly contaminated clay packed into two types of experimental cells, a rigid-wall stainless steel tube and a flexible-wall Teflon tube in a pressurized chamber. Both tubes are 5 cm in diameter and approximately 25 cm long. This laboratory apparatus was developed as a 1D physical model for contaminant transport in a cylindrical matrix towards a fracture, which is represented by one end of the cylinder and serves as the outlet of vapor and contaminant. The clay was contaminated with dissolved 1,2-dichloroethane (DCA) and bromide, and the columns were heated to more than 100 °C and then the top end was depressurized to atmospheric pressure to induce boiling. The outflow was condensed and analyzed for contaminant mass. The flexible-wall cell was confined to 100 kPa (gage), allowing equilibrium boiling temperatures of approximately 120 °C to be maintained. The clay was sampled before and after heating and extracted to determine the DCA distribution along the length of the column. During a typical test in the rigid-wall cell, internal temperatures and pressures along the column during heating reached the saturated vapor pressure curve. DCA concentrations in the recovered condensate were up to 12 times of the initial pore concentration in the clay. Less than 5% of non-volatile bromide was recovered. Significant removal of DCA and water occurred along the entire length of the clay column. This suggests that boiling was occurring in the clay matrix.
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Sirtuin-3 (SIRT3) expression is associated with overall survival in esophageal cancer.
Ann Diagn Pathol
PUBLISHED: 06-01-2013
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Sirtuin-3 (SIRT3) was immunostained in 94 samples of esophageal cancer tissues and semiquantified using the HSCORE method to evaluate the predictive value of SIRT3 expression levels on esophageal cancer outcome. The relationship between SIRT3 expression and the 5-year survival rate of postoperational esophageal cancer patients was assessed with the Kaplan-Meier method. High expression of SIRT3 is associated with a shorter survival time in esophageal cancer patients, as shown by the log-rank test (P = .007), and the level of SIRT3 expression was identified as an independent predictor for esophageal cancer outcome using Cox proportional hazards model analysis (relative risk, 2.061; 95% confidence interval, 1.050-4.046; P = .036). SIRT3 expression was associated with esophageal cancer outcome. The analysis of SIRT3 levels can help in the identification of patient subgroups that are at high risk for poor disease outcomes.
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Time-Course of Attentional Bias for Positive Social Words in Individuals with High and Low Social Anxiety.
Behav Cogn Psychother
PUBLISHED: 05-17-2013
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Background: Although accumulating research demonstrates the association between attentional bias and social anxiety, the bias for positive stimuli has so far not been adequately studied. Aims: The aim is to investigate the time-course of attentional bias for positive social words in participants with high and low social anxiety. Method: In a modified dot-probe task, word-pairs of neutral and positive social words were randomly presented for 100, 500, and 1250 milliseconds in a nonclinical sample of students to test their attentional bias. Results: Non-significant interaction of Group × Exposure Duration was found. However, there was a significant main effect of group, with significantly different response latencies between the high social anxiety (HSA) and low social anxiety (LSA) groups in the 100 ms condition, without for 500 or 1250 ms. With respect to attentional bias, the LSA group showed enhanced preferential attention for positive social words to which the HSA group showed avoidance in the 100 ms condition. In the 500 ms condition, preferential attention to positive social words was at trend in the LSA group, relative to the HSA group. Neither group showed attentional bias in the 1250 ms condition. Conclusions: These findings extend recent research about the attention training program and add to the empirical literature suggesting that the initial avoidance of positive stimuli may contribute to maintaining social anxiety.
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Synthesis and antiproliferative effect of novel curcumin analogues.
Chem. Pharm. Bull.
PUBLISHED: 05-11-2013
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Novel curcumin analogues with ?,?-unsaturated ketone moiety and/or ?,?-saturated ketone structure were synthesized from curcumin via alkylation at the central carbon and the phenolic hydroxy groups, and hydrogenation of ?,?-unsaturated ketone moiety. The antiproliferative activities were tested in five human solid tumor cell lines in vitro. Most of the compounds exhibited increased antiproliferative activities comparing with that of curcumin. Structure-activity relationship (SAR) analysis revealed that the ?,?-unsaturated ketone structure was not required for antiproliferative activity of these curcumin analogues. Among these compounds, 1,7-bis(3-methoxy-4-(3-(4-methylpiperazinyl-1-yl)propoxy)phenyl)-4,4-dibenzylheptane-3,5-dione (16f) was the most effective one with IC50 value below 1?µM, which was 9- to 81-fold more potent than curcumin.
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Hair mercury concentrations and associated factors in an electronic waste recycling area, Guiyu, China.
Environ. Res.
PUBLISHED: 04-25-2013
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Toxic heavy metals are released to the environment constantly from unregulated electronic waste (e-waste) recycling in Guiyu, China, and thus may contribute to the elevation of mercury (Hg) and other heavy metals levels in human hair. We aimed to investigate concentrations of mercury in hair from Guiyu and potential risk factors and compared them with those from a control area where no e-waste processing occurs.
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Magnesium coated bioresorbable phosphate glass fibres: investigation of the interface between fibre and polyester matrices.
Biomed Res Int
PUBLISHED: 04-19-2013
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Bioresorbable phosphate glass fibre reinforced polyester composites have been investigated as replacement for some traditional metallic orthopaedic implants, such as bone fracture fixation plates. However, composites tested revealed loss of the interfacial integrity after immersion within aqueous media which resulted in rapid loss of mechanical properties. Physical modification of fibres to change fibre surface morphology has been shown to be an effective method to improve fibre and matrix adhesion in composites. In this study, biodegradable magnesium which would gradually degrade to Mg(2+) in the human body was deposited via magnetron sputtering onto bioresorbable phosphate glass fibres to obtain roughened fibre surfaces. Fibre surface morphology after coating was observed using scanning electron microscope (SEM). The roughness profile and crystalline texture of the coatings were determined via atomic force microscope (AFM) and X-ray diffraction (XRD) analysis, respectively. The roughness of the coatings was seen to increase from 40 ± 1?nm to 80 ± 1?nm. The mechanical properties (tensile strength and modulus) of fibre with coatings decreased with increased magnesium coating thickness.
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Mitochondrial haplotypes may modulate the phenotypic manifestation of the LHON-associated m.14484T>C (MT-ND6) mutation in Chinese families.
Mitochondrion
PUBLISHED: 04-19-2013
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Mitochondrial m.14484T>C (MT-ND6) mutation has been associated with Lebers hereditary optic neuropathy. Previous investigations revealed that the m.14484T>C mutation is a primary factor underlying the development of optic neuropathy but is not sufficient to produce a clinical phenotype. However, mitochondrial haplogroups have been proposed to modulate the phenotypic manifestation of the m.14484T>C mutation. Here, we performed the clinical, genetic evaluation and complete mitochondrial genome sequence analysis of 41 Han Chinese pedigrees carrying the m.14484T>C mutation. These families exhibited a wide range of penetrances and expressivities of optic neuropathy. The average ratio between affected male/female matrilineal relatives from 41 families was 2:1. The penetrance of optic neuropathy in these Chinese pedigrees ranged from 5.6% to 100%, with the average of 23.8%. Furthermore, the age-of-onset for optic neuropathy varied from 4 to 44 years, with the average of 19.3 years. Sequence analysis of their mitochondrial genomes identified distinct sets of polymorphisms belonging to ten Eastern Asian haplogroups, indicating that the m.14484T>C mutation occurred through recurrent origins and founder events. We showed that mitochondrial haplogroups M9, M10 and N9 increased the penetrance of optic neuropathy in these Chinese families. In particular, these mitochondrial haplogroup specific variants: m.3394T>C (MT-ND1), m.14502T>C (MT-ND4) and m.14693A>G (MT-TE) enhanced the penetrance of visual loss in these Chinese families. These data provided the direct evidence that mitochondrial modifiers modulate the variable penetrance and expressivity of optic neuropathy among Chinese pedigrees carrying the m.14484T>C mutation.
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Deqi sensations of transcutaneous electrical nerve stimulation on auricular points.
Evid Based Complement Alternat Med
PUBLISHED: 04-18-2013
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Deqi sensation, a psychophysical response characterized by a spectrum of different needling sensations, is essential for Chinese acupuncture clinical efficacy. Previous research works have investigated the component of Deqi response upon acupuncture on acupoints on the trunk and limbs. However, the characteristics of Deqi sensations of transcutaneous electrical nerve stimulation (TENS) on auricular points are seldom reported. In this study, we investigated the individual components of Deqi during TENS on auricular concha area and the superior scapha using quantitative measurements in the healthy subjects and depression patients. The most striking characteristics of Deqi sensations upon TENS on auricular points were tingling, numbness, and fullness. The frequencies of pressure, warmness, heaviness, and soreness were relatively lower. The dull pain and coolness are rare. The characteristics of Deqi were similar for the TENS on concha and on the superior scapha.
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A genome-wide methylation study on obesity: differential variability and differential methylation.
Epigenetics
PUBLISHED: 04-17-2013
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Besides differential methylation, DNA methylation variation has recently been proposed and demonstrated to be a potential contributing factor to cancer risk. Here we aim to examine whether differential variability in methylation is also an important feature of obesity, a typical non-malignant common complex disease. We analyzed genome-wide methylation profiles of over 470,000 CpGs in peripheral blood samples from 48 obese and 48 lean African-American youth aged 14-20 y old. A substantial number of differentially variable CpG sites (DVCs), using statistics based on variances, as well as a substantial number of differentially methylated CpG sites (DMCs), using statistics based on means, were identified. Similar to the findings in cancers, DVCs generally exhibited an outlier structure and were more variable in cases than in controls. By randomly splitting the current sample into a discovery and validation set, we observed that both the DVCs and DMCs identified from the first set could independently predict obesity status in the second set. Furthermore, both the genes harboring DMCs and the genes harboring DVCs showed significant enrichment of genes identified by genome-wide association studies on obesity and related diseases, such as hypertension, dyslipidemia, type 2 diabetes and certain types of cancers, supporting their roles in the etiology and pathogenesis of obesity. We generalized the recent finding on methylation variability in cancer research to obesity and demonstrated that differential variability is also an important feature of obesity-related methylation changes. Future studies on the epigenetics of obesity will benefit from both statistics based on means and statistics based on variances.
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Identification and characterization of the actinomycin G gene cluster in Streptomyces iakyrus.
Mol Biosyst
PUBLISHED: 04-09-2013
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The gene cluster directing actinomycin G biosynthesis in Streptomyces iakyrus has been identified and sequenced. It contains one actinomycin synthetase I (ACMS I) gene and two copies of ACMS II and III genes. Genetic analysis demonstrates a unique partnership between the putative hydroxylation and chlorination activities as both acmG8 and acmG9 genes need to be transcribed for the biosynthesis of actinomycin G2-3, respectively.
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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.