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Find video protocols related to scientific articles indexed in Pubmed.
Comparative analysis of the pathogenic mechanisms of street rabies virus strains with different virulence levels.
Biomed. Environ. Sci.
PUBLISHED: 10-25-2014
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To characterize two strains of street rabies virus (RABV) isolated from the brain tissue of cattle from Inner Mongolia. Differences in the histopathological and ultrastructural changes in the brain tissue of infected mice were determined to reveal variation in the pathogenesis of infection between street rabies virus strains.
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[Traffic injuries of pre-hospital treatment in the urban area of Beijing].
Beijing Da Xue Xue Bao
PUBLISHED: 10-22-2014
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To evaluate the current condition of urban road traffic injuries (RTIs) according to Beijing Emergency Medical Center (BEMC) from Jan. 1, 2004 to Dec. 31, 2010, analyze the social characteristics and explore the possible methods for prevention and improvement.
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[Nerve baby-sitter in reverse end-to-side neurorrhaphy preserves the structure of denervated muscle in rats].
Beijing Da Xue Xue Bao
PUBLISHED: 10-22-2014
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To explore the protected effect of sensory baby-sitter in reverse end-to-side fashion on denervated muscle.
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A Novel All-trans Retinoid Acid Derivative N-(3-trifluoromethyl- phenyl)- Retinamide Inhibits Lung Adenocarcinoma A549 Cell Migration through Down-regulating Expression of Myosin Light Chain Kinase.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-09-2014
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To observe the effects of a novel all-trans retinoid acid (ATRA) derivative, N-(3-trifluoromethyl-phenyl)- retinamide (ATPR), on lung adenocarcinoma A549 cells and to explore the potential mechanism of ATPR inhibiting of A549 cell migration.
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Caspr4 interaction with LNX2 modulates the proliferation and neuronal differentiation of mouse neural progenitor Cells.
Stem Cells Dev.
PUBLISHED: 10-04-2014
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Contactin associated protein 4 (Caspr4), also known as contactin associated protein like protein (CNTNAP4), is expressed in various regions of the brain. Recent reports suggest that CNTNAP4 is a susceptibility gene of autism spectrum disorders (ASDs). However, the molecular function of Caspr4 in the brain has yet to be identified. In this study, we show an essential role of Caspr4 in neural progenitor cells (NPCs). Caspr4 is expressed in NPCs in the subventricular zone (SVZ), a neurogenic region in developing cortex. Knocking-down of Caspr4 enhances the proliferation of NPCs derived from the SVZ of embryonic day 14 (E14) mouse. Neuronal differentiation is increased by overexpression of Caspr4, but decreased by knocking-down of Caspr4 in cultured mouse NPCs. Transfection of the intracellular domain of Caspr4 (C4ICD) rescues the abnormal decreased neuronal differentiation of in Caspr4-knocking down NPCs. Ligand of Numb protein X2 (LNX2), a binding partner of Numb, interacts with Caspr4 in a PDZ domain dependent manner and plays a similar role to Caspr4 in NPCs. Moreover, transfection of LNX2 rescues the decreased neuronal differentiation in Caspr4-knocking down NPCs. In contrast, transfection of C4ICD fails to do so in LNX2-knocking down NPCs. These results indicate that Caspr4 inhibits neuronal differentiation in a LNX-dependent manner. Therefore, this study reveals a novel role of Caspr4 through LNX2 in NPCs, which may link to in the pathogenesis of ASDs.
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Cartilage Regeneration of Adipose-Derived Stem Cells in the TGF-?1-Immobilized PLGA-Gelatin Scaffold.
Stem Cell Rev
PUBLISHED: 10-01-2014
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Articular cartilage has restricted self-regenerative capacity; therefore, treatment of cartilage lesions is a great challenge in the field of orthopedics. In the present study, we evaluate the enhancing effect of a transforming growth factor-beta 1 (TGF-?1)-immobilized scaffold, fabricated by incorporating TGF-?1-loaded gelatin microspheres into PLGA framework, on the differentiation of adipose-derived stem cells (ASCs) into chondrocytes. Significant increase in cell proliferation was observed in the TGF-?1-immobilized PLGA-gelatin scaffold, as compared with the ASC-seeded non-TGF-?1-immobilized PLGA-gelatin scaffold. When chondrogenic differentiation of ASCs was evaluated for both constructs, sulfated glycosaminoglycan (sGAG) content was significantly higher in the TGF-?1-immobilized scaffold. This study showed that ASCs containing the TGF-?1-immobilized scaffold better promoted cartilage regeneration in defective articular cartilage, which is assessed by histological observation. Based on the above results, we conclude that TGF-?1-immobilized PLGA-gelatin scaffold seeded with ASCs considerably enhances the quality of the tissue-engineered cartilage, therefore, advancing the field of cartilage tissue engineering.
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Particulate matter mass and chemical component concentrations over four Chinese cities along the western Pacific coast.
Environ Sci Pollut Res Int
PUBLISHED: 09-18-2014
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China has witnessed rapid economic growth in the past three decades, especially in coastal areas. Particulate matter (PM) pollution is becoming increasingly serious in China's cities along the western Pacific coast with the rapid development of China's society and economy. This study analyzed PM (PM10 and PM2.5) in terms of their mass and chemical composition in four coastal Chinese cities. The goal was to study the spatial variation and characteristics of PM pollution in sites under different levels of economic development and in diverse natural environments. A distinct trend for concentrations of PM and related chemical species was observed and increased from south to north in Haikou, Ningbo, Qingdao, and Tianjin. Secondary inorganic aerosols, crustal materials, and organic matter dominated the composition of both PM10 and PM2.5. Crustal materials were the most abundant species in the northern coastal areas because these areas have less vegetation cover and lower humidity than southern coastal areas. The presence of high SO4 (2-)/nitrate (NO3 (-)) concentrations indicated that the burning of coals gives significant contributions to PM10 and PM2.5. The differences observed in the characteristics of PM pollution in these coastal cities are probably caused by different levels of industrial and urban development.
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EORTC QLQ-BM22 quality of life evaluation and pain outcome in patients with bone metastases from breast cancer treated with zoledronic acid.
In Vivo
PUBLISHED: 09-06-2014
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We assessed the effect of zoledronic acid on quality of life (QOL) and pain outcome in breast cancer patients with bone metastases using the European Organization for Research and Treatment of Cancer bone metastases module (EORTC QLQ-BM22).
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Vitamin D Prevents Podocyte Injury Via Regulation Of Macrophage M1/M2 Phenotype In Diabetic Nephropathy Rats.
Endocrinology
PUBLISHED: 09-04-2014
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Increasing evidences suggest the heterogeneity of macrophage phenotype and function ultimately determines the outcome of diabetic nephropathy (DN). The study aimed to investigate the effects of vitamin D on macrophages M1/M2 phenotype and its role in preventing podocytes impairment in streptozocin (STZ)-induced DN rats. Calcitriol, a bioactive 1,25-dihydroxyvitamin D3, ameliorated proteinuria and renal damage, as well as reversed the decline of both nephrin and podocin, crucial structural proteins in podocytes. DN rats showed increased infiltrating macrophages with M1 phenotype characterized by elevated expressions of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-?(TNF-?) in glomeruli and interstitium, which were inhibited after calcitriol treatment. Interestingly, calcitriol promoted M2 macrophages activation with enhanced expressions of CD163, arginase-1 (Arg-1) and mannose receptor (MR) at week 18 but not at week 8 or 14. The ratio of CD163/CD68 considered as the proportion of M2 macrophages was about 2.9 fold higher at week 18 after calcitriol treatment. Furthermore, the protein expression of iNOS, a crucial marker of M1 macrophages, was negatively correlated with the expression of either nephrin or podocin, while CD163, referring to M2 macrophages, was positively correlated. In vitro, 1,25-dihydroxyvitamin D3 switched high glucose-induced M1 macrophages toward an M2 phenotype in either U937 derived macrophages or RAW264.7 cells. Our results suggest that vitamin D not only reduces macrophages infiltration, inhibits M1 macrophages activation, but also enhances M2 macrophages phenotype to protect against podocyte injury.
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Using an improved Source Directional Apportionment method to quantify the PM2.5 source contributions from various directions in a megacity in China.
Chemosphere
PUBLISHED: 09-02-2014
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The transport of particulate matter (PM) and chemical species is an essential mechanism for determining the fate of PM pollutants and their effects. To determine source transport quantitatively, an ambient PM2.5 dataset from a megacity in China was analysed using a novel method called "Source Directional Apportionment" (SDA). The SDA method is developed in this work to quantify contributions of each source category from various directions. The three steps of SDA are (1) to estimate source categories and time series of source contributions to PM with a factor analysis model, (2) to identify directions by trajectory cluster analysis and (3) to quantify source directional contributions for each source category by combining the time series of source contributions to the back trajectories in each direction. For PM2.5 in Chengdu, crustal dust, vehicular exhaust, coal combustion and secondary sulphate are all important contributors to PM; secondary nitrate and cement dust are relatively less influential. Four potential source directions were identified in Chengdu during the sampling period from 2009 to 2011. The percentages of source directional contributions from Directions 1-4 (northeast, southwest to south, southwest and west) were estimated as follows: crustal dust (7.9%, 9.1%, 6.4% and 6.2%, respectively), cement dust (1.0%, 1.2%, 1.3% and 1.1%, respectively), vehicular exhaust (6.4%, 6.0%, 5.6% and 7.0%, respectively), secondary sulphate (5.1%, 5.2%, 5.6% and 8.6%, respectively) and secondary nitrate (2.0%, 2.4%, 2.5% and 2.3%, respectively). Finally, the source directional contributions to important chemical species were quantified to determine their transport from sources to receptor.
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Outcome prediction by the transcript level of BCR-ABL at 3 months in patients with chronic myeloid leukemia treated with imatinib--a single institution historical experience.
Leuk. Res.
PUBLISHED: 07-29-2014
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The BCR-ABL transcript level (? 10%) at 3 months after tyrosine kinase inhibitors can predict long term outcome in the patients with chronic myeloid leukemia in chronic phase (CML-CP). However, the significance of transcript level was still not determined in different risk groups of patients. A total of 299 patients with CML-CP were enrolled and stratified according to prior interferon-? (IFN) treatment, age, and interval time between diagnosis and imatinib treatment to investigate the prediction value of BCR-ABL transcript level for overall survival (OS), event-free survival (EFS), progression-free survival (PFS). Univariate and multivariate analysis proved that BCR-ABL transcript level at 3 months were associated with the treatment outcome. However, in the patients with prior IFN treatment, younger age, and longer interval between diagnosis and IM treatment, the predictive value of transcript value remain obscure in terms of EFS, PFS and OS, respectively, as well as cumulative incidence of PCyR, CCR, MMR and CMR. In conclusion, the transcript level of BCR-ABL at 3 months could serve as a predictive parameter, but should be used with caution.
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Sprouty2 protein is downregulated in human squamous cell carcinoma of the head and neck and suppresses cell proliferation in vitro.
Mol Med Rep
PUBLISHED: 07-21-2014
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Sprouty2 is known for its tumor-suppressing effect in various human malignant diseases. In head and neck squamous cell carcinoma (HNSCC), the role of sprouty2 in tumorigenesis and clinical implication remains elusive. The aim of the present study was to investigate the expression of sprouty2 in patients with HNSCC and its function in vitro. Quantitative analysis of mRNA expression of sprouty2 was performed on frozen tumor samples from 42 patients with HNSCC and 19 with oral verrucous hyperplasia (OVH) with paired counterparts of normal mucosa. Downregulation of sprouty2 expression was demonstrated in 79% of HNSCC samples and in 58% of OVH samples compared with paired samples of normal mucosa. Enhanced expression of sprouty2 protein suppressed the growth of HNSCC cells and signaling of the phosphorylated AKT pathway. Following transfection of the sprouty2 plasmid, HNSCC cells were more sensitive to sorafenib, a tyrosine kinase inhibitor of Raf and vascular endothelial growth factor receptor. The present study suggested that sprouty2 expression was downregulated and behaved as a tumor suppressor in HNSCC. Sprouty2 expression in tumor cells enhanced sensitivity to sorafenib. Further studies are required to define the clinical impact of sprouty2 in patients with HNSCC.
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Tetrabromobisphenol A disrupts vertebrate development via thyroid hormone signaling pathway in a developmental stage-dependent manner.
Environ. Sci. Technol.
PUBLISHED: 07-03-2014
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Data concerning effects of tetrabromobisphenol A (TBBPA) on thyroid hormone (TH)-dependent vertebrate development have been limited, although TBBPA has been demonstrated in vitro to disrupt the TH signaling pathway at the transcriptional level. In this study, we investigated the effects of TBBPA on T3-induced and spontaneous Xenopus laevis metamorphosis, which share many similarities with TH-dependent development in higher vertebrates. In a 6-day T3-induced metamorphosis assay using premetamorphic tadpoles, 10-1000 nM TBBPA exhibited inhibitory effects on T3-induced expression of TH-response genes and morphological changes in a concentration-dependent manner, with a weak stimulatory action on tadpole development and TH-response gene expression in the absence of T3 induction. In a spontaneous metamorphosis assay, we further found that TBBPA promoted tadpole development from stage 51 to 56 (pre- and prometamorphic stages) but inhibited metamorphic development from stage 57 to 66 (metamorphic climax). These results strongly show that TBBPA, even at low concentrations, disrupts TH-dependent development in a developmental stage-dependent manner, i.e., TBBPA exhibits an antagonistic activity at the developmental stages when animals have high endogenous TH levels, whereas it acts as an agonist at the developmental stages when animals have low endogenous TH levels. Our study highlights the adverse influences of TBBPA on TH-dependent development in vertebrates.
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Further insights into the composition, source and toxicity of pahs in size-resolved PM in a megacity in China.
Environ. Toxicol. Chem.
PUBLISHED: 07-01-2014
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Concentrations of PM10 and PM2.5 and 16 polycyclic aromatic hydrocarbons (PAHs) were measured. The average concentrations of PM10 and PM2.5 reached 209.75 ?g/m(3) and 141.87 ?g/m(3) ; and those of ?PAHs were 41.46 ng/m(3) for PM10 and 36.77 ng/m(3) for PM2.5 . The mass ratio concentrations were 219.23 ?g/g and 311.01 ?g/g in PM10 and PM2.5 , respectively. Three sources and their contributions for PAHs were obtained. For individual-input mode, diesel exhaust source contributed 46.77% (PM10 ) and 41.12% (PM2.5 ) for mass concentration; 48.69% (PM10 ) and 39.47% (PM2.5 ) for mass ratio concentration while gasoline exhaust source were 31.02% (PM10 ), 39.47% (PM2.5 ) and 28.95% (PM10 ), 36.46% (PM2.5 ), respectively for each concentration. As to coal combustion source, 22.22% and 19.41% to PM10 and PM2.5 for mass concentration, as well as 22.36% as 15.89% for mass ratio concentration, were observed. For combined-input mode, same source categories were obtained. Source contributions to PM10 and PM2.5 were diesel exhaust (40.70% and 36.64% for mass concentration; 49.19% and 38.47% for mass ratio concentration), gasoline exhaust (35.09% and 38.47%; 32.50% and 33.43%) and coal combustion (24.21% and 24.89%; 18.31% and18.17%). Source risk assessment showed that vehicle emission was a significant contributor. The findings can help elucidate sources of PAHs and provide good evidence for further applications of Unmix model and deeper studies about PAHs. This article is protected by copyright. All rights reserved.
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Copper-catalyzed aerobic oxidative amination of sp3 C-H bonds: efficient synthesis of 2-hetarylquinazolin-4(3H)-ones.
Org. Lett.
PUBLISHED: 06-30-2014
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An efficient synthesis of 2-hetarylquinazolin-4(3H)-ones via copper-catalyzed direct aerobic oxidative amination of sp(3)C-H bonds has been developed. This tandem oxidation-amination-cyclization transformation represents a straightforward protocol to prepare 2-hetaryl-substituted quinazolinones from easily available 2-aminobenzamides and (2-azaaryl)methanes.
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Genetic diversity and evolution of two capsid protein genes of citrus tristeza virus isolates from China.
Arch. Virol.
PUBLISHED: 06-26-2014
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The genetic diversity and population structure of citrus tristeza virus (CTV) isolates from China were investigated based on partial sequences spanning the C-terminal end of p61 and the complete sequences of the CPm and CP genes. Phylogenetic analysis revealed five known groups (RB, T30, T36, HA and VT) and one new group (VI) consisting of only Chinese CTV isolates. Incongruent phylogenetic trees coupled with recombination analysis suggested several recombination events in the CPm gene. Positive selection was detected at codon 9 of CPm and codons 31, 41 and 68 of CP. The widespread CTV subpopulation AT-1 found in China has a unique amino acid insertion at the C-terminus of p61, which could increase CTV population complexity with implications for the evolutionary history of the virus. Our results suggest relevant roles for gene flow, purifying selection and recombination in shaping the CTV population in China.
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Strong Lewis acid air-stable cationic titanocene perfluoroalkyl(aryl)sulfonate complexes as highly efficient and recyclable catalysts for C-C bond forming reactions.
Dalton Trans
PUBLISHED: 06-20-2014
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A series of strong Lewis acid air-stable titanocene perfluoroalkyl(aryl)sulfonate complexes Cp2Ti(OH2)2(OSO2X)2·THF (X = C8F17, 1·THF; X = C4F9, 2·H2O·THF; X = C6F5, 3) were successfully synthesized by the treatment of Cp2TiCl2 with C8F17SO3Ag, C4F9SO3Ag and C6F5SO3Ag, respectively. In contrast to well-known titanocene bis(triflate), these complexes showed no change in open air over three months. TG-DSC analysis showed that 1·THF, 2·H2O·THF and 3 were thermally stable at 230 °C, 220 °C and 280 °C, respectively. Conductivity measurements showed that these complexes underwent ionic dissociation in CH3CN solution. X-ray analysis results confirmed that 2·H2O·THF and 3 were cationic. ESR spectra showed that the Lewis acidity of 1·THF (1.06 eV) was higher than that of Sc(3+) (1.00 eV) and Y(3+) (0.85 eV). UV/Vis spectra showed a significant red shift due to the strong complex formation between 10-methylacridone and 2·H2O·THF. Fluorescence spectra showed that the Lewis acidity of 2 (?(em) = 477 nm) was higher than that of Sc(3+) (?(em) = 474 nm). These complexes showed high catalytic ability in various carbon-carbon bond forming reactions. Moreover, they show good reusability. Compared with 1·THF, 2·H2O·THF and 3 exhibit higher solubility and better catalytic activity, and will find broad applications in organic synthesis.
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The future of quantum dots in drug discovery.
Expert Opin Drug Discov
PUBLISHED: 06-16-2014
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The rapid development of drug discovery today is inseparable from the interaction of advanced particle technologies and new drug synthesis protocols. Quantum dots (QDs) are regarded as a unique class of fluorescent labels, with unique optical properties such as high brightness and long-term colloidal and optical stability; these are suitable for optical imaging, drug delivery and optical tracking, fluorescence immunoassay and other medicinal applications. More importantly, QD possesses a rich surface chemistry property that is useful for incorporating various drug molecules, targeting ligands, and additional contrast agents (e.g., MRI, PET, etc.) onto the nanoparticle surface for achieving targeted and traceable drug delivery therapy at both cellular and systemic levels. In recent times, the advancement of QD technology has promoted the use of functionalized nanocrystals for in vivo applications. Such research is paving the way for drug discovery using various bioconjugated QD formulations. In this editorial, the authors highlight the current research progress and future applications of QDs in drug discovery.
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Enhanced biocatalytic production of L-cysteine by Pseudomonas sp. B-3 with in situ product removal using ion-exchange resin.
Bioprocess Biosyst Eng
PUBLISHED: 05-15-2014
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Bioconversion of DL-2-amino-?(2)-thiazoline-4-carboxylic acid (DL-ATC) catalyzed by whole cells of Pseudomonas sp. was successfully applied for the production of L-cysteine. It was found, however, like most whole-cell biocatalytic processes, the accumulated L-cysteine produced obvious inhibition to the activity of biocatalyst and reduced the yield. To improve L-cysteine productivity, an anion exchange-based in situ product removal (ISPR) approach was developed. Several anion-exchange resins were tested to select a suitable adsorbent used in the bioconversion of DL-ATC for the in situ removal of L-cysteine. The strong basic anion-exchange resin 201 × 7 exhibited the highest adsorption capacity for L-cysteine and low adsorption for DL-ATC, which is a favorable option. With in situ addition of 60 g L(-1) resin 201 × 7, the product inhibition can be reduced significantly and 200 mmol L(-1) of DL-ATC was converted to L-cysteine with 90.4 % of yield and 28.6 mmol L(-1 )h(-1) of volumetric productivity. Compared to the bioconversion without the addition of resin, the volumetric productivity of L-cysteine was improved by 2.27-fold using ISPR method.
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Visible light-mediated C-H difluoromethylation of electron-rich heteroarenes.
Org. Lett.
PUBLISHED: 05-09-2014
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A novel method for visible-light photoredox-catalyzed difluoromethylation of electron-rich N-, O-, and S-containingheteroarenes under mild reaction conditions is developed. Mechanistic investigation indicates that the net C-H difluoromethylation proceeds through an electrophilic radical-type pathway.
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[Arthroscopic treatment of snyder II type of superior labrum anterior and posterior injury by absorbable anchors through anterior and posterior approach].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-07-2014
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To evaluate the effectiveness of arthroscopic treatment of superior labrum anterior and posterior (SLAP) injury by absorbable anchors through anterior and posterior approach.
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Associations of nm23H1, VEGF-C, and VEGF-3 receptor in human prostate cancer.
Molecules
PUBLISHED: 05-06-2014
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We studied the expression of the non-metastatic clone 23 type 1 (nm23H1) gene, vascular endothelial growth factor (VEGF)-C, and its receptor VEGFR-3 using an in situ hybridization technique and immunohistochemical analyses with prostate cancer tissues and adjacent benign tissues of 52 human archival cases. The association between VEGF-C expression, microlymphatic count (MLC), and staining intensity for nm23H1 and VEGFR-3 was used to evaluate tumor metastasis and survival rate. MLC values were significantly higher in tumorous tissue than in non-cancerous tissue. VEGF-C mRNA, VEGFR-3, and nm23H1 were highly expressed in tumorous tissue. VEGFR-3 expression was greater in VEGF-C mRNA-positive tumors than in VEGF-C mRNA-negative tumors. The association of VEGFR-3 expression with VEGF-C mRNA and MLC suggested that the poor prognosis and tumor metastasis associated with VEGFR-3 expression may be due, in part, to its role in promoting angiogenesis. VEGF-C expression was significantly associated with tumor lymphangiogenesis, angiogenesis, and immune response as a potent multifunctional stimulating factor in prostate cancer. Expression of nm23H1 was significantly inversely correlated with lymph node metastasis. Furthermore, there was a strong negative correlation between the expression of nm23H1, VEGF-C mRNA, and MLC. These findings provide important information for prophylactic, diagnostic, and therapeutic strategies for prostate cancer.
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Metal-free aerobic oxidative C-N bond cleavage of tertiary amines for the synthesis of N-heterocycles with high atom efficiency.
Org. Biomol. Chem.
PUBLISHED: 05-03-2014
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An efficient metal-free aerobic oxidative C-N bond cleavage of tertiary amines has been developed to construct N-heterocycles using molecular oxygen as the sole oxidant with high atom efficiency, in which all of the three alkyl groups in tertiary amines can be utilized and transformed into N-heterocycles.
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Copper-catalyzed aerobic oxidative inert C-C and C-N bond cleavage: a new strategy for the synthesis of tertiary amides.
Chemistry
PUBLISHED: 04-17-2014
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A copper-catalyzed aerobic oxidative amidation reaction of inert C-C bonds with tertiary amines has been developed for the synthesis of tertiary amides, which are significant units in many natural products, pharmaceuticals, and fine chemicals. This method combines C-C bond activation, C-N bond cleavage, and C-H bond oxygenation in a one-pot protocol, using molecular oxygen as the sole oxidant without any additional ligands.
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Facile fabrication and enhanced photosensitized degradation performance of the g-C3N4-Bi2O2CO3 composite.
Dalton Trans
PUBLISHED: 04-15-2014
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Flower-like Bi2O2CO3 and g-C3N4-Bi2O2CO3 microspheres with a high adsorption ability were synthesized using a facile method, and their dye-induced photosensitized degradation activity under visible light irradiation was evaluated. The as-synthesized samples were characterized by XRD, FT-IR, FESEM, TEM (HRTEM), UV-vis DRS and nitrogen adsorption-desorption techniques. It was found that the activity of Bi2O2CO3 was significantly enhanced due to the generation of g-C3N4-Bi2O2CO3 heterostructures. The dye-sensitization and the presence of g-C3N4 are beneficial for the visible-light excited process. The enhancement of photocatalytic performance is ascribed to the proper matching of the energy levels of the dye, Bi2O2CO3 and g-C3N4 that facilitates the separation and transfer of photogenerated electrons and holes at the heterojunctions. The results of the present study give insights that are beneficial for the design of heterostructured materials.
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Synthesis, characterization and anti-proliferative activity of heterocyclic hypervalent organoantimony compounds.
Eur J Med Chem
PUBLISHED: 04-06-2014
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Three heterocyclic hypervalent organoantimony chlorides RN(CH2C6H4)2SbCl (2a R = t-Bu, 2b R = Cy, 2c R = Ph) and their chalcogenide derivatives [RN(CH2C6H4)2Sb]2O (3a R = t-Bu, 3b R = Cy, 3c R = Ph) were synthesized and characterized by techniques such as (1)H NMR, (13)C NMR, X-ray diffraction, and elemental analysis. It is found that the anti-proliferative activity detected over these compounds can be attributed to the coordination bond between the antimony and nitrogen atoms of these compounds. Moreover, a preliminary study on mechanistic action suggests that the inhibition effect is ascribable to cell cycle arrest and cell apoptosis.
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Pd(0)-Catalyzed radical aryldifluoromethylation of activated alkenes.
Chem. Commun. (Camb.)
PUBLISHED: 03-14-2014
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A Pd(0)-catalyzed intramolecular aryldifluoromethylation of activated alkenes under mild reaction conditions has been developed. This reaction provides a new method for construction of a variety of difluoromethylated oxindoles. Mechanistic investigations indicate that a difluoromethyl radical, which was triggered by Pd(0), initiated the cascade sequence through an addition to the alkene.
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CCL20 and CXCL8 synergize to promote progression and poor survival outcome in patients with colorectal cancer by collaborative induction of the epithelial-mesenchymal transition.
Cancer Lett.
PUBLISHED: 03-02-2014
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Liver metastases represent the major cause of death in patients with colorectal cancer (CRC). Recent studies have suggested that the chemotactic responses of tumor cells are necessary for metastatic spread to the liver, and CCL20 and CXCL8 have a strong association with CRC metastasis. The aim of our study was to identify the mechanisms by which CCL20 and CXCL8 synergize to promote metastatic progression and evaluated their potential as prognostic markers for CRC patients. The abilities of CCL20 and CXCL8 to promote CRC cell progression and epithelial-mesenchymal transition(EMT)phenotype were analyzed in vitro. Possible signaling pathways were investigated with specific pathway inhibitors and small interfering RNA (siRNA). 213 Patients with CRC who underwent surgery were enrolled for analysis of CCL20, CXCL8 and E-cadherin expressions in tumor tissues. Prognostic factors were then identified. CCL20 or CXCL8 alone was not sufficient to induce complete EMT in CRC cells, but both of them could coordinately induce EMT-like phenotype that was required to maintain CRC cell proliferation, migration and invasion. PI3K/AKT-ERK1/2 pathway crosstalk was demonstrated to be responsible for this process. Coexpression of CCL20 and CXCL8 was negatively correlated with E-cadherin expression in human CRC tissues. CRC patients with coexpression of CCL20 and CXCL8 were more likely to develop liver metastases and both coexpression was an independent high-risk factor for a most poor prognosis. CCL20 and CXCL8 synergize to promote CRC metastatic progression by coordinated induction of EMT via PI3K/AKT-ERK1/2 signaling axis. Detection of both coexpressions can be used to predict clinical outcomes in CRC patients.
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MicroRNA-100 resensitizes resistant chondrosarcoma cells to cisplatin through direct targeting of mTOR.
Asian Pac. J. Cancer Prev.
PUBLISHED: 02-27-2014
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Chondrosarcomas are malignant cartilage-forming tumors of bone which exhibit resistance to both chemotherapy and radiation treatment. miRNAs have been well demonstrated to regulate gene expression and play essential roles in a variety of biological processes, including proliferation, differentiation, migration, cell cycling and apoptosis. In this study, we obtained evidence that miR-100 acts as a tumor suppressor in human chondrosarcomas. Interestingly, cisplatin resistant chondrosarcoma cells exhibit decreased expression of miR-100 compared with parental cells. In addition, we identified mTOR as a direct target of miR-100. Overexpression of miR-100 complementary pairs to the 3' untranslated region (UTR) of mTOR, resulted in sensitization of cisplatin resistant cells to cisplatin. Moreover, recovery of the mTOR pathway by overexpression of S6K desensitized the chondrosarcoma cells to cisplatin, suggesting the miR-100-mediated sensitization to cisplatin dependent on inhibition of mTOR. In summary, the present studies highlight miR-100 as a tumor suppressor in chondrosarcoma contributing to anti-chemoresistance. Overexpression of miR-100 might be exploited as a therapeutic strategy along with cisplatin-based combined chemotherapy for the treatment of clinical chondrosarcoma patients.
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Physically constrained source apportionment (PCSA) for polycyclic aromatic hydrocarbon using the Multilinear Engine 2-species ratios (ME2-SR) method.
Sci. Total Environ.
PUBLISHED: 02-25-2014
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An improved physically constrained source apportionment (PCSA) technology using the Multilinear Engine 2-species ratios (ME2-SR) method was proposed and applied to quantify the sources of PM10- and PM2.5-associated polycyclic aromatic hydrocarbons (PAHs) from Chengdu in winter time. Sixteen priority PAH compounds were detected with mean ?PAH concentrations (sum of 16 PAHs) ranging from 70.65ng/m(3) to 209.58ng/m(3) and from 59.17ng/m(3) to 170.64ng/m(3) for the PM10 and PM2.5 samples, respectively. The ME2-SR and positive matrix factorization (PMF) models were employed to estimate the source contributions of PAHs, and these estimates agreed with the experimental results. For the PMF model, the highest contributor to the ?PAHs was vehicular emission (81.69% for PM10, 82.06% for PM2.5), followed by coal combustion (12.68%, 12.11%), wood combustion (5.65%, 4.45%) and oil combustion (0.72%, 0.88%). For the ME2-SR method, the highest contributions were from diesel (43.19% for PM10, 47.17% for PM2.5) and gasoline exhaust (34.94%, 32.44%), followed by wood combustion (8.79%, 6.37%), coal combustion (12.46%, 12.37%) and oil combustion (0.80%, 1.22%). However, the PAH ratios calculated for the factors extracted by ME2-SR were closer to the values from actual source profiles, implying that the results obtained from ME2-SR might be physically constrained and satisfactory.
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Identification of animal rabies in Inner Mongolia and analysis of the etiologic characteristics.
Biomed. Environ. Sci.
PUBLISHED: 02-21-2014
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To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2011, and analyze their etiological characteristics.
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The Hippo effector Yorkie activates transcription by interacting with a histone methyltransferase complex through Ncoa6.
Elife
PUBLISHED: 02-17-2014
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The Hippo signaling pathway regulates tissue growth in Drosophila through the transcriptional coactivator Yorkie (Yki). How Yki activates target gene transcription is poorly understood. Here, we identify Nuclear receptor coactivator 6 (Ncoa6), a subunit of the Trithorax-related (Trr) histone H3 lysine 4 (H3K4) methyltransferase complex, as a Yki-binding protein. Like Yki, Ncoa6 and Trr are functionally required for Hippo-mediated growth control and target gene expression. Strikingly, artificial tethering of Ncoa6 to Sd is sufficient to promote tissue growth and Yki target expression even in the absence of Yki, underscoring the importance of Yki-mediated recruitment of Ncoa6 in transcriptional activation. Consistent with the established role for the Trr complex in histone methylation, we show that Yki, Ncoa6, and Trr are required for normal H3K4 methylation at Hippo target genes. These findings shed light on Yki-mediated transcriptional regulation and uncover a potential link between chromatin modification and tissue growth.
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Regulatory roles of miRNA in the human neural stem cell transformation to glioma stem cells.
J. Cell. Biochem.
PUBLISHED: 02-13-2014
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To investigate the expressional alternation of microRNAs (miRNA) during the malignant transformation and development of human glioma, we measured miRNA expression profile as well as mRNA expression profile in normal human neural stem cells (hNSCs) and human glioma stem cells (hGSCs). We found 116 miRNA up-regulated and 62 miRNA down-regulated in GSCs. On the other hand, we identified 1,372 mRNA down-regulated, and 1,501 mRNA up-regulated in GSCs compared to those in NSCs. We then analyzed the pathways and the predicted target genes of the miRNAs which differ significantly in expression between GSCs and NSCs using the statistical enrichment methods. These target mRNAs are involved in many cancer-related signaling pathways, such as cell cycle, axon guidance, glioma development, adhesion junction, MAPK and Wnt signaling. Furthermore, we obtained the differently expressed miRNA-target relationships according to the ? value which is used to calculate the regulation extent of miRNA-target and using the databases of miRanda, Targetscans and Pictar. Among the top 10 miRNA-target relationships, hsa-miR-198 and its potential targeted gene DCX and NNAT were selected for validation, and NNAT was found to be the direct target of miR-198. Finally, the functional roles of miR-155-5p and miR-124-3p whose expressions altered significantly between GSCs and NSCs were addressed. Our results provide new clues for the potential mechanisms involved in the origin and development of glioma. Clinically, the altered miRNAs may serve as potential targets and diagnostic tools for novel therapeutic strategies of glioblastoma.
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Silver-mediated radical aryltrifluoromethylthiolaton of activated alkenes.
Org. Lett.
PUBLISHED: 02-05-2014
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The first example of silver-mediated oxidative aryltrifluoromethylthiolation of activated alkenes to produce valuable trifluoromethylthiole-containing oxindoles was developed. Mechanistic investigations indicated that this novel transformation proceeded through a unique F3CS(•) radical addition path, thus providing a practical and easy-handling method to generate a F3CS(•) radical in the laboratory.
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The role of calpains in traumatic brain injury.
Brain Inj
PUBLISHED: 01-25-2014
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This article attempts to provide a framework that will help to illustrate the roles of calpains in the process of traumatic brain injury (TBI).
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Different accumulation profiles of multiple components between pericarp and seed of Alpinia oxyphylla capsular fruit as determined by UFLC-MS/MS.
Molecules
PUBLISHED: 01-14-2014
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Plant secondary metabolites are known to not only play a key role in the adaptation of plants to their environment, but also represent an important source of active pharmaceuticals. Alpinia oxyphylla capsular fruits, made up of seeds and pericarps, are commonly used in traditional East Asian medicines. In clinical utilization of these capsular fruits, inconsistent processing approaches (i.e., hulling pericarps or not) are employed, with the potential of leading to differential pharmacological effects. Therefore, an important question arises whether the content levels of pharmacologically active chemicals between the seeds and pericarps of A. oxyphylla are comparable. Nine secondary metabolites present in A. oxyphylla capsular fruits, including flavonoids (e.g., tectochrysin, izalpinin, chrysin, apigenin-4',7-dimethylether and kaempferide), diarylheptanoids (e.g., yakuchinone A and B and oxyphyllacinol) and sesquiterpenes (e.g., nootkatone), were regarded as representative constituents with putative pharmacological activities. This work aimed to investigate the abundance of the nine constituents in the seeds and pericarps of A. oxyphylla. Thirteen batches of A. oxyphylla capsular fruits were gathered from different production regions. Accordingly, an ultra-fast high performance liquid chromatography/quadrupole tandem mass spectrometry (UFLC-MS/MS) method was developed and validated. We found that: (1) the nine secondary metabolites were differentially concentrated in seeds and fruit capsules; (2) nootkatone is predominantly distributed in the seeds; in contrast, the flavonoids and diarylheptanoids are mainly deposited in the capsules; and (3) the content levels of the nine secondary metabolites occurring in the capsules varied greatly among different production regions, although the nootkatone levels in the seeds were comparable among production regions. These results are helpful to evaluating and elucidating pharmacological activities of A. oxyphylla capsular fruits. Additionally, it may be of interest to elucidate the mechanisms involved in the distinct accumulation profiles of these secondary metabolites between seeds and pericarps.
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Targeting of circulating hepatocellular carcinoma cells to prevent postoperative recurrence and metastasis.
World J. Gastroenterol.
PUBLISHED: 01-14-2014
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Currently, the main treatment for hepatocellular carcinoma (HCC) involves the surgical removal of tumors or liver transplantation. However, these treatments are often not completely curative, as they are associated with a risk for postoperative recurrence and metastasis. Circulating tumor cells (CTCs) are increasingly recognized as the main source for recurrence and metastasis after radical hepatectomies are performed. Many studies have demonstrated the association between the presence of either pre- or postoperative CTCs and an increased risk for HCC recurrence. To improve the therapeutic outcome of HCC, a personalized, comprehensive and multidisciplinary approach should be considered, involving the application of appropriate diagnostic and therapeutic measures targeting HCC CTCs in different stages throughout the course of treatment. This article proposes some HCC CTC-based strategies for the treatment of HCC, including the monitoring of HCC CTCs before, during and after radical hepatectomy, therapeutic targeting of HCC CTCs, prevention of the generation and colonization of CTCs, as well as the use of CTC indexes for the selection of indications, prediction of prognoses, and planning of individualized therapeutic regimens. Innovation and technological development of therapies targeting CTCs, as well as their translation into clinical practice, will help to effectively reduce postoperative recurrence and metastasis, and significantly prolong the survival of HCC patients.
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Structure-activity relations in binding of perfluoroalkyl compounds to human thyroid hormone T3 receptor.
Arch. Toxicol.
PUBLISHED: 01-13-2014
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Perfluoroalkyl compounds (PFCs) have been shown to disrupt thyroid functions through thyroid hormone receptor (TR)-mediated pathways, but direct binding of PFCs with TR has not been demonstrated. We investigated the binding interactions of 16 structurally diverse PFCs with human TR, their activities on TR in cells, and the activity of perfluorooctane sulfonate (PFOS) in vivo. In fluorescence competitive binding assays, most of the 16 PFCs were found to bind to TR with relative binding potency in the range of 0.0003-0.05 compared with triiodothyronine (T3). A structure-binding relationship for PFCs was observed, where fluorinated alkyl chain length longer than ten, and an acid end group were optimal for TR binding. In thyroid hormone (TH)-responsive cell proliferation assays, PFOS, perfluorohexadecanoic acid, and perfluorooctadecanoic acid exhibited agonistic activity by promoting cell growth. Furthermore, similar to T3, PFOS exposure promoted expression of three TH upregulated genes and inhibited three TH downregulated genes in amphibians. Molecular docking analysis revealed that most of the tested PFCs efficiently fit into the T3-binding pocket in TR and formed a hydrogen bond with arginine 228 in a manner similar to T3. The combined in vitro, in vivo, and computational data strongly suggest that some PFCs disrupt the normal activity of TR pathways by directly binding to TR.
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Chemical characteristic and toxicity assessment of particle associated PAHs for the short-term anthropogenic activity event: During the Chinese New Year's Festival in 2013.
Sci. Total Environ.
PUBLISHED: 01-13-2014
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PM10 and PM2.5 samples were simultaneously collected during a period which covered the Chinese New Year's (CNY) Festival. The concentrations of particulate matter (PM) and 16 polycyclic aromatic hydrocarbons (PAHs) were measured. The possible source contributions and toxicity risks were estimated for Festival and non-Festival periods. According to the diagnostic ratios and Multilinear Engine 2 (ME2), three sources were identified and their contributions were calculated: vehicle emission (48.97% for PM10, 53.56% for PM2.5), biomass & coal combustion (36.83% for PM10, 28.76% for PM2.5), and cook emission (22.29% for PM10, 27.23% for PM2.5). An interesting result was found: although the PAHs are not directly from the fireworks display, they were still indirectly influenced by biomass combustion which is affiliated with the fireworks display. Additionally, toxicity risks of different sources were estimated by Multilinear Engine 2-BaP equivalent (ME2-BaPE): vehicle emission (54.01% for PM10, 55.42% for PM2.5), cook emission (25.59% for PM10, 29.05% for PM2.5), and biomass & coal combustion source (20.90% for PM10, 14.28% for PM2.5). It is worth to be noticed that the toxicity contribution of cook emission was considerable in Festival period. The findings can provide useful information to protect the urban human health, as well as develop the effective air control strategies in special short-term anthropogenic activity event.
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Source contributions and spatiotemporal characteristics of PAHs in sediments: Using three-way source apportionment approach.
Environ. Toxicol. Chem.
PUBLISHED: 01-10-2014
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Polycyclic aromatic hydrocarbon (PAHs) were measured in sediments from 29 sites throughout Taihu Lake in China during 2 seasons to investigate spatiotemporal characteristics and source contributions using a 3-way source apportionment approach to positive matrix factorization (PMF3). Seasonal and spatial variations of levels and toxicity suggested higher individual carcinogenic PAH concentrations and toxic equivalent quantity (TEQ) in the flooding season. Three-way PAHs dataset (PAH species, spatial variability, and seasonal variability) was analyzed by PMF3, and its results were compared with a widely used 2-way model (PMF2). Consistent results were observed: vehicular emission was the most important contributor (67.08% by PMF2 and 61.83% by PMF3 for the flooding season; 54.21% by PMF2 and 52.94% by PMF3 for dry season), followed by coal combustion and wood combustion in both seasons. The PMF-cluster analysis was employed to investigate spatial variability of source contributions. Findings can introduce the 3-way approach to apportion sources of PAHs and other persistent organic pollutants (POPs) in sediments, offering the advantage of accounting for information on 3-way datasets.
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Validated method to measure yakuchinone A in plasma by LC-MS/MS and its application to a pharmacokinetic study in rats.
Chem Cent J
PUBLISHED: 01-10-2014
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Yakuchinone A has a plethora of beneficial biological effects. However, the pharmacokinetic (PK) data of yakuchinone A still remain unknown so far. Furthermore, the quantification of yakuchinone A in biological samples has not been reported in the literature. Therefore, in the present study we aimed to develop a new method for the fast, efficient and accurate assessment of yakuchinone A concentration in plasma, as a means for facilitating the PK evaluation of yakuchinone A.
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Identification of known chemicals and their metabolites from Alpinia oxyphylla fruit extract in rat plasma using liquid chromatography/tandem mass spectrometry (LC-MS/MS) with selected reaction monitoring.
J Pharm Biomed Anal
PUBLISHED: 01-09-2014
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Alpinia oxyphylla (Yizhi) capsularfruits are commonly used in traditional medicine. Pharmacological studies have demonstrated that A. oxyphylla capsularfruits have some beneficial roles. Besides volatile oil, sesquiterpenes, diarylheptanoids and flavonoids are main bioactive constituents occurring in the Yizhi capsularfruits. The representative constituents include tectochrysin, izalpinin, chrysin, apigenin-4',7-dimethylether, kaempferide, yakuchinone A, yakuchinone B, oxyphyllacinol and nootkatone. Their content levels in the fruit and its pharmaceutical preparations have been reported by our group. The nine phytochemicals are also the major components present in the Yizhi alcoholic extracts, which have anti-diarrheal activities. However, the fates of these constituents in the body after oral or intravenous administration remain largely unknown. In the present study, we focus on these phytochemicals albeit other concomitant compounds. The chemicals and their metabolites in rat plasma were identified using liquid chromatography/tandem mass spectrometry with selected reaction monitoring mode after orally administered Yizhi extract to rats. Rat plasma samples were treated by methanol precipitation, acidic or enzymatic hydrolysis. This target analysis study revealed that: (1) low or trace plasma levels of parent chemicals were measured after p.o. administration of Yizhi extract, Suoquan capsules and pills to rats; (2) flavonoids and diarylheptanoids formed mainly monoglucuronide metabolites; however, diglucuronide metabolites for chrysin, izalpinin and kaempferide were also detected; (3) metabolic reduction of Yizhi diarylheptanoids occurred in rats. Yakuchinone B was reduced to yakuchinone A and then to oxyphyllacinol in a stepwise manner and subsequently glucuronidated by UDP-glucuronosyl transferase. Further research is needed to characterize the UDP-glucuronosyl transferase and reductase involved in the biotransformation of Yizhi chemicals.
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Izalpinin from fruits of alpinia oxyphylla with antagonistic activity against the rat bladder contractility.
Afr J Tradit Complement Altern Med
PUBLISHED: 01-01-2014
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Alpinia oxyphylla (Zingiberaceae), an herbaceous perennial plant, its capsular fruit is commonly used in traditional Chinese medicine for the treatment of different urinary incontinence symptoms including frequency, urgency and nocturia. These symptoms are similar to the overactive bladder syndrome. In our lab, we found that the 95% ethanol extract of the capsular fruits exhibited significant anti-muscarinic activity. Some constituents in capsular fruits including flavonoids (e.g., izalpinin and tectochrysin), diarylheptanoids (e.g., yakuchinone A and yakuchinone B) and sesquiterpenes (e.g., nootkatone), are regarded as representative chemicals with putative pharmacological activities.
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Anterolateral acromial approach in locking plate fixation of proximal humerus fractures in elderly patients.
Acta Orthop Belg
PUBLISHED: 12-20-2013
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We describe our experience with a two-incision anterolateral acromial approach in locking plate fixation of proximal humeral fractures in older adults. Mean time between injury and surgery was 3.08 +/- 1.24 days. A proximal anterolateral transverse incision and a more distal longitudinal incision were used. A locking plate was inserted along the lateral side of the humerus from the proximal incision to the distal fragment of the humerus. Mean operation time was 62.37 +/- 19.05 minutes. There were no instances of axillary nerve paralysis or infection. Postoperative imaging results were satisfactory in all cases. Three obese patients experienced fat liquefaction at the incision site. Mean total Neer score one year after surgery was 88.16 +/- 5.05. We conclude that the two-incision anterolateral acromial approach with use of locking plates appears to be an effective means to treat proximal humeral fractures in older adults.
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LSD1 Regulates Pluripotency of Embryonic Stem/Carcinoma Cells through Histone Deacetylase 1-Mediated Deacetylation of Histone H4 at Lysine 16.
Mol. Cell. Biol.
PUBLISHED: 11-04-2013
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LSD1 is essential for the maintenance of pluripotency of embryonic stem (ES) or embryonic carcinoma/teratocarcinoma (EC) cells. We have previously developed novel LSD1 inhibitors that selectively inhibit ES/EC cells. However, the critical targets of LSD1 remain unclear. Here, we found that LSD1 interacts with histone deacetylase 1 (HDAC1) to regulate the proliferation of ES/EC cells through acetylation of histone H4 at lysine 16 (H4K16), which we show is a critical substrate of HDAC1. The LSD1 demethylase and HDAC1 deacetylase activities were both inactivated if one of them in the complex was chemically inhibited in ES/EC cells or in reconstituted protein complexes. Loss of HDAC1 phenocopied the selective growth-inhibitory effects and increased the levels of H3K4 methylation and H4K16 acetylation of LSD1 inactivation on ES/EC cells. Reduction of acetylated H4K16 by ablation of the acetyltransferase males absent on the first (MOF) is sufficient to rescue the growth inhibition induced by LSD1 inactivation. While LSD1 or HDAC1 inactivation caused the downregulation of Sox2 and Oct4 and induction of differentiation genes, such as FOXA2 or BMP2, depletion of MOF restored the levels of Sox2, Oct4, and FoxA2 in LSD1-deficient cells. Our studies reveal a novel mechanism by which LSD1 acts through the HDAC1- and MOF-mediated regulation of H4K16 acetylation to maintain the pluripotency of ES/EC cells.
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[Generation and characterization of peripheral nerve animal model of pure motor/sensory nerve fibers].
Beijing Da Xue Xue Bao
PUBLISHED: 10-19-2013
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To generate peripheral nerve animal model of pure motor nerve fibers/pure sensory nerve fibers, and identify them.
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[Human umbilical cord blood mononuclear cell transplantation promotes long-term neurobehavioral functional development of newborn SD rats with hypoxic ischemic brain injury].
Zhonghua Er Ke Za Zhi
PUBLISHED: 10-15-2013
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To explore the effect of human umbilical cord blood mononuclear cells (UCBMC) promoting nerve behavior function and brain tissue recovery of neonatal SD rat with hypoxic ischemic brain injury (HIBI).
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Theoretical investigation of the structures, stabilities, and NLO responses of calcium-doped pyridazine: Alkaline-earth-based alkaline salt electrides.
J. Mol. Graph. Model.
PUBLISHED: 09-26-2013
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Currently, whether alkaline-earth-doped compounds with electride characteristics are novel candidates for high-performance nonlinear optical (NLO) materials is unknown. In this paper, using quantum chemical computations, we show that: when doping calcium atoms into a family of alkaline-substituted pyridazines, alkaline-earth-based alkaline salt electrides M-H3C4N2?Ca (MH, Li, and K) with distended excess electron clouds are formed. Interestingly, from the triplet to the singlet state, the chemical valence of calcium atom changes from +1 to 0, and the dipole moment direction (?0) of the molecule reverses for each M-H3C4N2?Ca. Changing pyridazine from without (H4C4N2?Ca) to with one alkaline substituent (M-H3C4N2?Ca, MLi and K), the ground state changes from the triplet to the singlet state. The alkaline earth metal doping effect (electride effect) and alkaline salt effect on the static first hyperpolarizabilities (?0) demonstrates that (1) the ?0 value is increased approximately 1371-fold from 2 (pyridazine, H4C4N2) to 2745au (Ca-doped pyridazine, H4C4N2?Ca), (2) the ?0 value is increased approximately 1146-fold from 2 in pyridazine (H4C4N2) to 2294au in an Li-substituted pyridazine (Li-H3C4N2), and (3) the ?0 value is increased 324-(MLi) and 106-(MK) fold from 826 (MLi) and 2294au (MK) to 268,679 (MLi) and 245,878au (MK), respectively, from the alkalized pyridazine (M-H3C4N2) to the Ca-doped pyridazine (M-H3C4N2?Ca). These results may provide a new means for designing high-performance NLO materials.
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Room-temperature synthesis of flower-like BiOX (X?Cl, Br, I) hierarchical structures and their visible-light photocatalytic activity.
Inorg Chem
PUBLISHED: 09-19-2013
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A simple method for facile synthesis of three-dimensional (3D) bismuth oxyhalide (BiOX, X?Cl, Br, I) hierarchical structures at room temperature has been developed. Under the influence of L-lysine surfactant, the bismuth and halogen (Cl, Br, I) sources hydrolyze and self-assemble into flower-like hierarchical architectures within 10 min. The resulted materials were characterized by XRD, FESEM, TEM, UV-vis DRS, and N2 adsorption-desorption techniques. We found that l-lysine is indispensable for their formation and the amount of HX has great effect on the final morphology. The BiOX (X?Cl, Br, I) hierarchical architectures are composed of single-crystalline nanoplates. We propose an amino-and-carboxyl structure-directing mechanism for the formation of the hierarchical structures. To evaluate the photocatalytic activity of the as-prepared materials, rhodamine-B was employed as a probe dye for degradation under visible light. All of the BiOX (X?Cl, Br, I) with 3D architectures show higher photocatalytic activities than their sheet-like counterparts. The superior activity is ascribed to the better light-harvesting capacity of the 3D hierarchical structures. The adopted method can be applied for large-scale generation of novel structures of similar kinds in a facile manner.
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Steroidogenic enzyme AKR1C3 is a novel androgen receptor-selective coactivator that promotes prostate cancer growth.
Clin. Cancer Res.
PUBLISHED: 08-30-2013
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Castration-resistant prostate cancer (CRPC) may occur by several mechanisms including the upregulation of androgen receptor (AR), coactivators, and steroidogenic enzymes, including aldo keto reductase 1C3 (AKR1C3). AKR1C3 converts weaker 17-keto androgenic precursors to more potent 17-hydroxy androgens and is consistently the major upregulated gene in CRPC. The studies in the manuscript were undertaken to examine the role of AKR1C3 in AR function and CRPC.
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Bilateral stereotactic radiofrequency amygdalohippocampectomy for a patient with bilateral temporal lobe epilepsy.
Epilepsia
PUBLISHED: 08-20-2013
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To search for a method for treatment of bilateral temporal lobe epilepsy (BTLE), we report one patient with BTLE experienced bilateral stereotactic radiofrequency amygdalohippocampectomy (SAHE). Neuropsychological examinations were performed before and 5 days, and 6, 18, and 48 months after operation. No seizure occurred in the follow-up time, and no long-term memory and intelligence deficits were found except for a transient decline of the scores immediately after operation. Because severe damage of memory could be caused by bilateral resection surgery, bilateral SAHE should be considered as a possible approach for the treatment of BTLE. However, further studies with accumulation of cases are needed, especially in the detailed assessment of neuropsychological function.
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Prehospital road traffic injuries among the elderly in Beijing, China: data from the Beijing Emergency Medical Center, 2004-2010.
Chin. Med. J.
PUBLISHED: 08-09-2013
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Road traffic injuries (RTIs) are a worldwide issue associated with increasing development and motorization. However, statistical studies do not include any analyses of Beijings geriatric population. Using data from the Beijing Emergency Medical Center, we present the main characteristics of traffic injuries involving the elderly in Beijing. We also provide objective information for those concerned with the safety of traffic systems and the prevention of traffic injuries.
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Association study on the DLG4 gene and schizophrenia in the Chinese Han population.
Psychiatr. Genet.
PUBLISHED: 08-08-2013
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Abnormal expressions of the N-methyl-D-aspartate receptor and its interacting postsynaptic density (PSD) molecules have been hypothesized to be involved in the pathophysiology of schizophrenia. Few studies have carried out association studies with DLG4 gene (coding PSD-95 protein) and sought to validate the results with Asian schizophrenia patients.
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Historical trends of concentrations, source contributions and toxicities for PAHs in dated sediment cores from five lakes in western China.
Sci. Total Environ.
PUBLISHED: 07-24-2013
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In this work, sixteen U.S. EPA priority PAH compounds in the dated sediment cores were detected from five lakes in western China. In most lakes, the concentrations of the total PAHs (?PAHs) increased from the deep layers to the surface sediments. Two source categories, i.e. vehicular emission and biomass & domestic coal combustion were identified by Unmix, a factor analysis receptor model to explore the source contributions of PAHs in the dated sediments. The source apportionment results showed that biomass & domestic coal combustion contributed larger proportion of PAHs in the five lakes. The toxicities of PAHs in the dated sediments, assessed by BaP equivalent (BaPE) values showed that the BaPE increased gradually from the deep layers to the surface sediments in most lakes. For the first effort, the contribution of each source to BaPE was apportioned by Unmix-BaPE method, and the result indicated that the vehicular emission posed the highest toxic risk. The percentage contribution of vehicular emission for PAHs and BaPE also increased from the deep layers to the surface sediments, while biomass & domestic coal combustion exhibited the opposite tendency.
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Crude dietary polysaccharide fraction isolated from jackfruit enhances immune system activity in mice.
J Med Food
PUBLISHED: 07-24-2013
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Crude polysaccharides (PSs) were isolated from the fruit pulp of jackfruit, and their chemical composition determined and evaluated for an immune regulatory activity in mice. The PSs were isolated from water extracts of jackfruit pulp (JFP) using the ethanol precipitation method. The resulting precipitates were further purified by dialysis and protein depletion by the Sevage method. The phenol-sulfuric method was used to determine the content of the PSs. The composition of PSs was determined by the Sephadex-G200 column chromatography and high-performance liquid chromatography methods. The thymus index and macrophage phagocytic function methods in mice were used to evaluate the immune regulatory activity of JFP-PSs. The JFP-PSs content in jackfruit was about 21% (w/w) and the yield of crude PSs was 3.91%. The single molecular mass weight PS was the main constituent of JFP-PSs. The major monosaccharide residues were rhamnose, glucose, galactose, and arabinose. The JFP-PSs enhanced the thymus weight index and the phagocytic rate after 30 days of subchronic p.o. administration to mice at 4.5 mg/kg. The JFP contains single molecular PS and JFP-PS has immune-stimulating activities in mice. These data suggest that at least some of the traditional uses of JFP can be ascribed to its immunomodulatory effects.
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Structures and nonlinear optical properties of the endohedral metallofullerene-superhalogen compounds Li@C60-BX4 (X = F, Cl, Br).
Phys Chem Chem Phys
PUBLISHED: 07-02-2013
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It has recently been demonstrated that superatoms, which can exhibit behaviors reminiscent of atoms in the periodic table, might have synthetic utility, and represent potential building blocks for the assembly of novel, nanostructured materials [Science 2004, 304, 84-87; Science 2005, 307, 231-235; J. Phys. Chem. C 2009, 113, 2664]. In this work, a new type of endohedral metallofullerene-superhalogen compound, Li@C60-BX4 (X = F, Cl, Br), is proposed and characterized using density functional theory. The electron transfer from Li@C60 to BX4 contributes greatly to the Li@C60-BX4 compound formation. Such compounds exhibit considerable stabilities with large binding energies and ionization potentials, as well as large HOMO-LUMO gaps. The investigation of the nonlinear optical (NLO) properties of Li@C60-BX4 reveals a strong dependence of the static first hyperpolarizability, ?0, on the atomic number of the involved halogen atom X. This means that one can enhance the first hyperpolarizabilities of the endohedral metallofullerene by introducing superhalogens. The present investigation may promote the development of novel nanomaterials with unusual properties (i.e. NLO properties), and enrich the knowledge of chemical bonds (for example, long-range interactions between trapped atoms in a C60 cage and the outside superatom motif).
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Effects of perfluorooctanesulfonate and perfluorobutanesulfonate on the growth and sexual development of Xenopus laevis.
Ecotoxicology
PUBLISHED: 06-24-2013
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Perfluorobutanesulfonate (PFBS), as a substitute for perfluorooctanesulfonate (PFOS), is widespread in the environment and biotic samples as well as PFOS. To investigate effects of PFOS and PFBS on the growth and sexual development of amphibians, we exposed Xenopus laevis tadpoles at a series of concentrations of PFOS and PFBS (0.1; 1; 100; 1,000 ?g/l) as well as 17-beta-estradiol (E2, 100 ng/l) and 5 alpha-androstan-17-beta-ol-3-one (DHT, 100 ng/l) from stage 46/47 to 2 months postmetamorphosis. We found that neither PFOS nor PFBS had a significant effect on the survival and growth. However, they caused hepatohistological impairment at higher concentrations (100; 1,000 ?g/l). Unlike E2, PFOS at all concentrations did not alter the sex ratio and induce intersex, but caused degeneration of spermatogonia in testes except for the lowest concentration. PFBS had no effect on the sex ratio and gonadal histology. PFOS and PFBS promoted expression of estrogen receptor (ER) and androgen receptor (AR), but not affected aromatase expression in the brain. The increase in expression of ER and AR suggests an increase in the responsiveness to the corresponding sex hormone and potential effects on sexual development. Our results show that PFBS as well as PFOS have adverse effects on hepato-histology and sexual development on X. laevis. Also, PFOS- and PFBS-induced increase in ER and AR expression highlights the need to further study effects of PFOS and PFBS on subsequently gonadal development, sexual dimorphism, and secondary sex characteristics in X. laevis. It is debatable that PFBS is widely used as a substitute of PFOS.
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Ultrasound assessment of injury to the posterior ligamentous complex in patients with mild thoracolumbar fractures.
J. Int. Med. Res.
PUBLISHED: 06-12-2013
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To assess the value of ultrasonographic imaging of the posterior ligamentous complex (PLC) to diagnose ligamentous injuries, in patients with mild thoracolumbar fractures.
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Tris(aceto-nitrile-?N)dichlorido(tri-phenyl-phosphane-?P)ruthenium(II) aceto-nitrile monosolvate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 06-01-2013
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In the title complex, [RuCl2(CH3CN)3(C18H15P)]·CH3CN, the coordination geometry of the Ru(II) atom is distorted octa-hedral, defined by one P atom from a tri-phenyl-phosphane ligand, three N atoms from three aceto-nitrile ligands and two Cl atoms. The three acetronitile ligands linearly bind to the Ru(II) atom, with Ru-N-C angles of 172.6?(2), 179.9?(2) and 171.4?(2)°.
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Environmental (anti-)androgenic chemicals affect germinal vesicle breakdown (GVBD) of Xenopus laevis oocytes in vitro.
Toxicol In Vitro
PUBLISHED: 05-31-2013
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Progesterone-induced germinal vesicle breakdown (GVBD) of Xenopus oocytes in vitro was used to study endocrine disrupting activity of chemicals in previous studies. In this study, we investigated for the first time effects of environmental androgens on oocyte maturation and effects of anti-androgens on androgen-induced oocyte maturation, using Xenopus GVBD in vitro. Trenbolone and nandrolone, two environmental androgens, were found to induce Xenopus GVBD at low concentrations. The potential of trenbolone to induce GVBD was approximately 100-fold lower than that of testosterone, while trenbolone had a several-fold lower potential than testosterone. Our findings have aroused new concerns for effects of environmental androgens on amphibian oocyte maturation at environmentally relevant concentrations, and suggested that Xenopus GVBD can be used to test androgenic activity of suspicious environmental androgens. Androgen receptor (AR) antagonist flutamide at 10 ?M only exhibited a weakly inhibitory effect on androgen-induced GVBD, while another known AR antagonist vinclozolin had no effect even if at high concentrations. The results show that Xenopus GVBD is not sensitive to AR-mediated environmental anti-androgens. In contrast to flutamide and vinclozolin, methoxychlor (a weaker AR antagonist) inhibited dramatically androgen-induced GVBD, suggesting that androgen-induced Xenopus GVBD can be used to study non-AR-mediated effects of chemicals on oocyte maturation.
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Sediments in concentrated green tea during low-temperature storage.
Food Chem
PUBLISHED: 05-19-2013
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The formation and the main chemical components of sediments, including reversible tea sediments (RTS) and irreversible tea sediments (IRS), in concentrated green tea during low-temperature storage were studied. RTS was mainly formed in the first 10days, and IRS was mainly formed between 20 and 40days of storage. The RTS were the primary sediment, contributing more than 90% of the total sediment. The RTS comprised of polyphenols, total sugar, caffeine, flavones and proteins, while the IRS mainly comprised of oxalates of Ca, Mg, Ga and Mn. The total mineral content in the IRS (17.1%) was much higher than that in the RTS (2.6%) after 80days of storage. The Ca, Mg, Mn and Ga contents in IRS were over 1.0% (w/w) each. About 75% of the IRS was soluble in 0.1M aqueous HCl, with the oxalate accounting for 68%. Minerals and oxalic acid were the crucial factors in the IRS formation.
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Quantitative analysis of the major constituents in Chinese medicinal preparation SuoQuan formulae by ultra fast high performance liquid chromatography/quadrupole tandem mass spectrometry.
Chem Cent J
PUBLISHED: 05-16-2013
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The SuoQuan formulae containing Fructus Alpiniae Oxyphyllae has been used to combat the urinary incontinence symptoms including frequency, urgency and nocturia for hundreds of years in China. However, the chemical information was not well characterized. The quality control marker constituent only focused on one single compound in the current Chinese Pharmacopeia. Hence it is prudent to identify and quantify the main constituents in this herbal product. This study aimed to analyze the main constituents using ultra-fast performance liquid chromatography coupled to tandem mass spectrometry (UFLC-MS/MS).
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Optimal graft length for anterior cruciate ligament reconstruction: a biomechanical study in beagles.
Orthopedics
PUBLISHED: 05-16-2013
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The anterior cruciate ligament (ACL) is a major ligament that helps maintain the stability of the knee joint. Injury to the ACL can be treated by replacing the torn ligament. This study determined the optimal flexor tendon length in the bone tunnel in ACL reconstruction.Autologous ACL reconstruction was performed using a flexor tendon in 54 male beagles, with the graft length in the bone tunnel at 5, 9, 13, 17, 21, and 25 mm (9 dogs per graft length). The maximum tensile strength and stiffness of the reconstructed joint (tibia-ACL-femur triad) were recorded at 45, 90, and 180 days after ACL reconstruction (6 joints per time point). The experiment also included an intact control group (3 dogs) and a control group tested immediately after the reconstruction (3 dogs). For the intact control group, the normal ACL (unreconstructed) and flexor tendon mechanical testing was performed. For the other control group, the normal ACL (unreconstructed) mechanical testing was performed first and then mechanical testing of the specimens was performed immediately after reconstruction. The maximum tensile strength and stiffness of the reconstructed tibia-ACL-femur triad increased with time after reconstruction, regardless of the graft length in the bone tunnel. Maximum tensile strength and stiffness of the grafts increased with graft length but reached a plateau at 17 mm. Optimal strength and stiffness of the reconstructed ACL are achieved with 17-mm grafts.
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Synthesis and structures of hypervalent organoantimony and organobismuth chlorides containing asymmetric C,E,C-chelating (E = O, S) ligands.
Dalton Trans
PUBLISHED: 05-10-2013
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Two asymmetric tridentate C,E,C-chelating ligand precursors, 1-Br-2-[(2-BrC6H4CH2E)CH2]C10H6 (E = O (1), E = S (2), were prepared in good yield. Lithiation of the two precursors was achieved by a reaction with n-BuLi, and was followed by treatment with SbCl3 or BiCl3 in a 1: 1molar ratio to give four air-stable hypervalent organoantimony and organobismuth chlorides with an asymmetric C,E,C-chelating ligand (E = O, S), i.e. (C6H4CH2OCH2C10H6)SbCl (3), (C6H4CH2SCH2C10H6)SbCl (4), (C6H4CH2OCH2C10H6)BiCl (5) and (C6H4CH2SCH2C10H6)BiCl (6). These compounds were characterized by NMR spectroscopy, elemental analysis and melting point determination. X-ray structure analysis of compounds 3-6 revealed that the donor atoms (O, S) are strongly coordinated to the metal atoms (Sb, Bi). Compounds 3-6 exhibit chirality and crystallize as racemic mixtures.
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Pluripotent stem cell protein Sox2 confers sensitivity to LSD1 inhibition in cancer cells.
Cell Rep
PUBLISHED: 05-05-2013
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Gene amplification of Sox2 at 3q26.33 is a common event in squamous cell carcinomas (SCCs) of the lung and esophagus, as well as several other cancers. Here, we show that the expression of LSD1/KDM1 histone demethylase is significantly elevated in Sox2-expressing lung SCCs. LSD1-specific inhibitors selectively impair the growth of Sox2-expressing lung SCCs, but not that of Sox2-negative cells. Sox2 expression is associated with sensitivity to LSD1 inhibition in lung, breast, ovarian, and other carcinoma cells. Inactivation of LSD1 reduces Sox2 expression, promotes G1 cell-cycle arrest, and induces genes for differentiation by selectively modulating the methylation states of histone H3 at lysines 4 (H3K4) and 9 (H3K9). Reduction of Sox2 further suppresses Sox2-dependent lineage-survival oncogenic potential, elevates trimethylation of histone H3 at lysine 27 (H3K27) and enhances growth arrest and cellular differentiation. Our studies suggest that LSD1 serves as a selective epigenetic target for therapy in Sox2-expressing cancers.
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The Hippo effector Yorkie controls normal tissue growth by antagonizing scalloped-mediated default repression.
Dev. Cell
PUBLISHED: 04-28-2013
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The Hippo tumor suppressor pathway restricts tissue growth by inactivating the transcriptional coactivator Yki. Although Sd has been implicated as a DNA-binding transcription factor partner for Yki and can genetically account for gain-of-function Yki phenotypes, how Yki regulates normal tissue growth remains a long-standing puzzle because Sd, unlike Yki, is dispensable for normal growth in most Drosophila tissues. Here we show that the yki mutant phenotypes in multiple developmental contexts are rescued by inactivation of Sd, suggesting that Sd functions as a default repressor and that Yki promotes normal tissue growth by relieving Sd-mediated default repression. We further identify Tgi as a cofactor involved in Sds default repressor function and demonstrate that the mammalian ortholog of Tgi potently suppresses the YAP oncoprotein in transgenic mice. These findings fill a major gap in Hippo-mediated transcriptional regulation and open up possibilities for modulating the YAP oncoprotein in cancer and regenerative medicine.
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Long-term variation of the levels, compositions and sources of size-resolved particulate matter in a megacity in China.
Sci. Total Environ.
PUBLISHED: 03-18-2013
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To investigate the long-term trends and variations of the levels, compositions, size distribution and sources of particulate matter (PM), long-term monitoring campaigns of PM10 and PM2.5 were performed in a megacity in China (Chengdu) during the period from 2009 to 2011. The average concentration of PM10 was 172.01±89.80 ?g/m(3) and that of PM2.5 was 103.15±59.83 ?g/m(3), with an average PM2.5/PM10 of 0.60. Enrichments of the important species indicated that the fractions of crustal elements were higher in PM10 than those in PM2.5, while the abundance of organic carbon (OC) and secondary ions was enriched in the fine PM. Quantitative source apportionments of both PM10 and PM2.5 were performed by PMF. PM10 and PM2.5 in Chengdu were influenced by similar source categories, and their percentage contributions were in the same order: crustal dust was the highest contributor, followed by vehicular exhaust, secondary sulfate, secondary nitrate and cement dust. Crustal dust and cement dust contributed a higher percentage to PM10 than to PM2.5, while vehicular exhaust and secondary particles provided higher percentage contributions to PM2.5. In addition, PMF-HCA was performed to investigate the characteristics of the sources of the clustered samples, identifying three periods: crustal dust dominant-period, secondary sulfate dominant-period and comprehensive source influenced-period. Planting, reduction of precursors, and banning high-emission vehicles should be implemented to control crustal dust, secondary particles and vehicular exhaust in Chengdu. Furthermore, the size-resolved and the period-resolved control would be more effective.
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[Biomechanical characteristics of hip prosthesis in hip arthroplasty treating elderly patients with Evans I-III intertrochanteric fracture of femur].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 03-12-2013
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To investigate the feasibility of hip arthroplasty in the treatment of elderly patients with Evans I-III intertrochanteric fracture of femur by analyzing its biomechanics characters.
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