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Find video protocols related to scientific articles indexed in Pubmed.
Production of Water-Soluble Few-Layer Graphene Mesosheets by Dry Milling with Hydrophobic Drug.
Langmuir
PUBLISHED: 11-20-2014
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A novel, fast and easy mechano-chemistry-based (dry milling) method has been developed to exfoliate graphene with hydrophobic drugs generating few layer graphene mesosheets (< 10 nm in thickness and ~ 1 µm in width). The electronic properties of the graphitic structure were partially preserved after the milling treatment compared to Graphene Oxide (GO) prepared by Hummers' method. Several characterization techniques such as thermogravimetric analysis (TGA), Raman spectroscopy, atomic force microscopy (AFM), Electron Microscopy (EM) and molecular dynamics simulation were used to characterize this material. The drug-exfoliated mesosheets were pharmacologically inactive offering a new approach for making water-soluble few-layer graphene mesosheets upon dry milling with hydrophobic drugs, mainly used as exfoliating agents.
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Growth and properties of Li, Ta modified (K,Na)NbO3 lead-free piezoelectric single crystals.
Phys Status Solidi Rapid Res Lett
PUBLISHED: 11-19-2014
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Li, Ta modified (K,Na)NbO3 single crystals with the size of 18 mm × 18 mm × 10 mm were successfully grown by top-seeded solution growth method, with orthorhombic-tetragonal phase transition temperature ~79 °C and Curie temperature ~276 °C. The electromechanical coupling factors k 33 and k t were found to be ~88% and ~65%, respectively. The piezoelectric coefficient d 33 for the [001]c poled crystals reached 255 pC/N. In addition, the electromechanical coupling factor exhibited high stability over the temperature range of -50 °C to 70 °C, making these lead free crystals good candidates for electromechanical applications.
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Vernier perceptual learning transfers to completely untrained retinal locations after double training: A "piggybacking" effect.
J Vis
PUBLISHED: 11-16-2014
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Perceptual learning, a process in which training improves visual discrimination, is often specific to the trained retinal location, and this location specificity is frequently regarded as an indication of neural plasticity in the retinotopic visual cortex. However, our previous studies have shown that "double training" enables location-specific perceptual learning, such as Vernier learning, to completely transfer to a new location where an irrelevant task is practiced. Here we show that Vernier learning can be actuated by less location-specific orientation or motion-direction learning to transfer to completely untrained retinal locations. This "piggybacking" effect occurs even if both tasks are trained at the same retinal location. However, piggybacking does not occur when the Vernier task is paired with a more location-specific contrast-discrimination task. This previously unknown complexity challenges the current understanding of perceptual learning and its specificity/transfer. Orientation and motion-direction learning, but not contrast and Vernier learning, appears to activate a global process that allows learning transfer to untrained locations. Moreover, when paired with orientation or motion-direction learning, Vernier learning may be "piggybacked" by the activated global process to transfer to other untrained retinal locations. How this task-specific global activation process is achieved is as yet unknown.
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Oxidative cross-dehydrogenative coupling between N-aryl tetrahydroisoquinolins and 5H-oxazol-4-ones through two methodologies: copper catalysis or a metal-free strategy.
Chem. Commun. (Camb.)
PUBLISHED: 11-04-2014
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A direct oxidative cross-dehydrogenative coupling (CDC) of N-aryl tetrahydroisoquinolins with 5H-oxazol-4-ones catalyzed by CuBr using air as the only oxidant has been developed, which could also proceed smoothly under a metal-free oxidative system with PhI(OAc)2 as the oxidant. A series of alkylated tetrahydroisoquinolin derivatives were obtained in good yields and excellent diastereoselectivities.
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[Effect of mitochondrial dysfunction of chondrocyte on cartilage degeneration].
Beijing Da Xue Xue Bao
PUBLISHED: 10-22-2014
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To evaluate the effect of chondrocyte mitochondrial dysfunction on the development of cartilage degeneration.
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All-normal-dispersion passive harmonic mode-locking 220??fs ytterbium fiber laser.
Appl Opt
PUBLISHED: 10-17-2014
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We report a stable passive second-harmonic mode-locked all-normal-dispersion ytterbium fiber laser based on nonlinear polarization evolution. This fiber laser has two polarization beam splitter output ports for optimizing the output spectrum 5 ps duration pulses with 187 mW average power being generated at the harmonic repetition rate of 99.6 MHz. By use of a pair of gratings to extracavity compensate the chirp, the pulse is further compressed to 220 fs. We measured that the peak-to-pedestal extinction of the radio frequency is about 80 dB corresponding to a pulse-to-pulse energy fluctuation of 0.32% and timing jitter of 3.2 ps.
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SFRP5 acts as a mature adipocyte marker but not as a regulator in adipogenesis.
J. Mol. Endocrinol.
PUBLISHED: 10-16-2014
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WNT/?-catenin signalling is involved in regulating adipogenesis, and its dysregulation occurs in obesity. Secreted frizzled-related protein 5 (SFRP5) is a WNT protein inhibitor; however, its role in adipogenesis and obesity is controversial. In this study, we observed that SFRP5 mRNA levels were increased in the fat tissues of obese humans and mice. Sfrp5 expression was gradually induced during differentiation of white and brown adipocytes and was highly increased in mature adipocytes rather than preadipocytes. However, the effects of the exogenous overexpression of Sfrp5 indicated that Sfrp5 may not directly regulate adipogenesis in vitro under the conditions studied. Moreover, SFRP5 did not inhibit the canonical WNT/?-catenin signalling pathway in preadipocytes. Subsequently, we measured the levels of circulating SFRP5 in obese patients and non-obese subjects using ELISA and did not find any significant difference. Collectively, these findings indicate that Sfrp5 represents a candidate for a mature adipocyte marker gene. Our data provide new evidence concerning the role of SFRP5 in adipogenesis of white and brown adipocytes and obesity.
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In vivo preventive effects of insect tea on buccal mucosa cancer in ICR mice.
J Cancer Res Ther
PUBLISHED: 10-15-2014
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Insect tea is a particular drink or health product in China and it is also used as Chinese medicine now. Its functional effects need to be proved.
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[Application of gene knockout technology in spermatogenesis-associated gene study].
Zhonghua Nan Ke Xue
PUBLISHED: 10-14-2014
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The gene approach to the pathogenesis of male infertility may bring about some strategies for the diagnosis and manage of the condition. Gene knockout technology is the mainstream method currently used in the study of gene function. Screening and identification of testis-specific genes and insights into their features and functions in spermatogenesis are significant for a further understanding of testicular functions and searching for new therapeutic targets for male reproductive disorders. This review focuses on the application of gene knockout technology in the study of spermatogenesis-associated genes.
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Tracing phosphate ions generated during DNA amplification and its simple use for visual detection of isothermal amplified products.
Chem. Commun. (Camb.)
PUBLISHED: 10-10-2014
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A yes/no answer for DNA isothermal amplification can be visually obtained with this phosphate ion-based method described in this communication. An extremely rapid detection for cross-priming isothermal amplification was proved and the feasibility of this strategy was systematically studied.
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Fast in situ generated ?-polylysine-poly (ethylene glycol) hydrogels as tissue adhesives and hemostatic materials using an enzyme-catalyzed method.
J Biomater Appl
PUBLISHED: 10-05-2014
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In this study, novel bio-inspired in situ hydrogels as tissue adhesives and hemostatic materials were designed and prepared based on ?-polylysine-grafted poly(ethylene glycol) and tyramine via enzymatic cross-linking. The enzymatic cross-linked method enabled fast gelation within seconds, which facilitated its therapeutic applications. By changing the cross-linking conditions, the storage modulus of the hydrogels could be tunable and the mechanical strength influenced the tissue adhesiveness of the hydrogels. Besides, the hydrogels showed fine network structures with appropriate pore sizes, which were thought to be a contributing factor to the strong adhesiveness. Benefiting from the strong mechanical properties and fine network structures, the ?-polylysine-grafted poly(ethylene glycol) and tyramine hydrogels exhibited superior wound-healing and hemostatic ability compared to conventional and commercially available medical materials. Moreover, indirect cytotoxicity assessment indicated that the ?-polylysine-grafted poly(ethylene glycol) and tyramine hydrogels were nontoxic to the L929 cell. These results demonstrated that the enzymatic cross-linked in situ ?-polylysine hydrogels hold high potential for tissue sealants and hemostatic materials.
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[Phenolic compounds in branches of Tamarix rasissima].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-03-2014
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To study the chemical constituents of the branches of Tamarix rasissima, repeated silica gel column chromatography, Sephadex LH-20 chromatography and recrystallization were applied for chemical constituents isolation and purification. Ten phenolic compounds were isolated from the n-BuOH fraction and their structures were elucidated by physical properties and spectra analysis such as UV, ESI-MS and NMR as monodecarboxyellagic acid (1), ellagic acid (2), 3, 3'-di-O-methylellagic acid (3), 3, 3'-di-O-methylellagic acid-4-O-beta-D-glucopyranoside (4), 3, 3'-di-O-methylellagic acid-4'-O-alpha-D-arabinfuranoside (5), ferulic acid (6), isoferulic acid (7), caffeic acid (8), 4-O-acetyl-caffeic acid (9), and 4-methyl-1, 2-benzenediol (10). All compounds except for isoferulic acid were isolated firstly from this plant except for isoferulic acid, and compounds 5, 9 and 10 were obtained from Tamarix genus for the first time.
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Copper-catalyzed intramolecular oxytrifluoromethylthiolation of unactivated alkenes.
Org. Lett.
PUBLISHED: 10-02-2014
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A mild, versatile, and convenient method for efficient intramolecular oxytrifluoromethylthiolation of unactivated alkenes catalyzed by Cu(OAc)2 has been developed. The reactions were carried out under aerobic conditions and formed a variety of isoxazolines bearing a -SCF3 substituent.
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[Bibliometric analysis of bacterial quantitative proteomics in English literatures].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 09-30-2014
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To analyze the worldwide advances on bacterial quantitative proteomics over the past fifteen years with bibliometric approach.
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Inhibition of Microtubule Dynamics Affects Podosome Belt Formation During Osteoclast Induction.
Cell Biochem. Biophys.
PUBLISHED: 09-27-2014
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Osteoclast is the only cell that can degrade bone tissue in vivo. Recent studies have shown the important role of cytoskeleton dynamics in osteolysis and the formation of podosome belt in osteoclasts. This process is regulated by the dynamic microtubule (MT) network. We treated osteoclast precursor cells Raw264.7 with low concentration of nocodazole (10 nM) and antineoplastic drug taxol (10 nM) to block MT turnover, and used end binding protein 1 fused to GFP to track the movement of microtubules in induced osteoclasts. We show that low concentrations of nocodazole and taxol interfere with the formation of podosome belt, and reduce TRAP activity of induced osteoclasts. These results suggest that the effect of taxol on MT dynamics may be used clinically to reduce osteoclast activity and potentially prevent development of osteoporosis and other metabolic bone diseases.
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Organocatalyzed Asymmetric Oxidative Coupling of ?-Csp(3)-H of Tertiary Amines to ?,?-Unsaturated ?-Butyrolactam: Synthesis of MBH-Type Products.
Org. Lett.
PUBLISHED: 09-26-2014
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A unique organocatalytic asymmetric oxidative cross-dehydrogenative coupling of a ?-Csp(3)-H bond of tertiary amines with ?,?-unsaturated ?-butyrolactams to generate Morita-Baylis-Hillman-type products has been realized for the first time. This method provides an efficient way to access a series of ?-heterocyclic optically active tetrahydroisoquinoline scaffolds.
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[One case of iatrogenic common carotid artery pseudoaneurysm which was removed and repaired according cervicothoracic combined approach].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-25-2014
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A 61-year-old patient with type I diabetes, diabetic nephropathy, thyroid hypofunction, chronic renal insufficiency anemia period, class IV heart function. During kidney dialysis, a little bleeding when puncture needle punctured the right common carotid artery, bleeding stopped after compression hemostasis. One week later, the patient complained of swollen neck, pain and difficult breathing. Ultrasonic examination suggested that local eminence beside the right common carotid artery, echoless and vascular interlinked; CDFI blood flow signal appeared the artery frequency spectrum, eddy current. Enhanced CT prompted right common carotid artery pseudoaneurysm, the contrast medium extravasated. The patient was diagnosed right common carotid artery pseudoaneurysm.
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[Mechanism of osteoclast in bone resorption].
Zhongguo Gu Shang
PUBLISHED: 09-23-2014
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Osteoclast, a huge coenocytes,originates from mononuclear macrophages or monocytic series hematopoietic precursor cell, plays an important role in the progree of bone resorption. Formation and abnormal activity of osteoclast may cause osteoprosis, rheumatoid arthritis and aseptic loosening after arthroplasty. Therefore, osteoclast is the target for treating these disease. At present, a lot of study on formation of osteoclast were reported, but the study on how to identify and degradation of bone tissue is not yet reported. Bone mineral are seen as important component of identifing osteoclast, and the research suggested that bone matrix is not the essential ingredients of activiting osteoclast, petri dish covered by vitronectin also can make osteoclast occure certain form of bone resorption, vitronectin plays an significant role in activiting osteoclast. Otherwise, the research found that swallowing and secretion of bone matrix degradation products is benefit for differentiation of osteoclast and maintain of function, and this may be therapeutic target for treatment of musculoskeletal disorders.
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The MEK/ERK signaling cascade is required for sonic hedgehog signaling pathway-mediated enhancement of proliferation and inhibition of apoptosis in normal keratinocytes.
Exp. Dermatol.
PUBLISHED: 09-21-2014
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Keratinocytes (KCs) play a critical role in maintaining the cutaneous structure and are involved in various physiological and pathologic processes of the skin. Many inflammatory skin diseases and skin cancers result from excessive proliferation and insufficient apoptosis of KCs. Recent data suggested that the sonic hedgehog (Shh) signaling pathway plays an essential role in the proliferation and apoptosis of normal KCs. However, the mechanism remains poorly defined. Here, we provide evidence that Shh signaling induces proliferation and inhibits apoptosis in normal KCs via cyclinD1 and Bcl2 in an extracellular signal-regulated kinase kinase (MEK) /extracellular signal-regulated kinase (ERK) dependent manner. In addition, the effect is independent of phosphinositide-3 kinase (PI3K)/AKT or Janus kinase/signal transducer and activator of transcription (JAK/STAT)1/3 pathways. Furthermore, we observed that epidermal growth factor receptor (EGFR) signaling modulates the activity of Shh signaling pathway; besides, Shh and EGFR signaling act additively to induce the ERK activation and the increases in cyclin D1 and Bcl2 thereby affecting proliferation and apoptosis in KCs in vitro. The present study suggests that the MEK/ERK1/2 activation is part of the mechanism of Shh signal-mediated proliferation and apoptosis in normal KCs. Our results may help to elucidate the regulatory mechanisms of the Shh pathway in normal KCs and the pathogenesis of related skin disorders. This article is protected by copyright. All rights reserved.
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The coordination of S-sulfhydration, S-nitrosylation, and phosphorylation of endothelial nitric oxide synthase by hydrogen sulfide.
Sci Signal
PUBLISHED: 09-11-2014
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The gasotransmitter hydrogen sulfide (H(2)S), which is generated by cystathionine ?-lyase (CSE), signals by modifying proteins through S-sulfhydration and potentially other mechanisms. A target protein for H(2)S is endothelial nitric oxide synthase (eNOS), an enzyme that generates nitric oxide (NO), which causes vasodilation. We investigated whether H(2)S-induced S-sulfhydration affected the S-nitrosylation and phosphorylation of eNOS and the functional effects of changes in these posttranslational modifications on eNOS activity. In vitro, different NO donors induced the S-nitrosylation of eNOS without affecting its S-sulfhydration, whereas the H(2)S donor sodium hydrosulfide (NaHS) decreased the S-nitrosylation of eNOS. Cys(443) was the primary S-sulfhydration site in eNOS and was one site that could be S-nitrosylated. Phosphorylation increases eNOS activity. Although exposure of eNOS-expressing HEK-293 cells to NaHS or vascular endothelial growth factor (VEGF) triggered the phosphorylation of wild-type and C443G-eNOS, VEGF did not affect the S-sulfhydration of eNOS and a mutant of eNOS that could not be phosphorylated was still S-sulfhydrated. eNOS can be present in cells in monomeric or dimeric form, but only eNOS dimers produce NO. In wild-type mice, eNOS proteins were predominantly dimerized, whereas eNOS from CSE-knockout (KO) mice, S-nitrosylated eNOS, and heterologously expressed C443G-eNOS was mostly monomeric. Accordingly, basal production of NO was lower in CSE-KO endothelial cells than in wild-type endothelial cells. Our data suggest that H(2)S increases eNOS activity by inducing the S-sulfhydration of eNOS, promoting its phosphorylation, inhibiting its S-nitrosylation, and increasing eNOS dimerization, whereas NO decreases eNOS activity by promoting the formation of eNOS monomers.
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Association study of miR?149 rs2292832 and miR?608 rs4919510 and the risk of hepatocellular carcinoma in a large?scale population.
Mol Med Rep
PUBLISHED: 09-04-2014
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Polymorphisms in pre?microRNAs (miRNAs) or mature miRNAs may influence miRNA processing or target binding, thus contributing to tumorigenesis and cancer development. The present study aimed to evaluate whether miR?149 rs2292832 (C>T) and miR?608 rs4919510 (G>C) are associated with the risk and clinical characteristics of hepatocellular carcinoma (HCC) in a large?scale population. miR?149 rs2292832 and miR?608 rs4919510 were genotyped in a total of 993 patients with HCC and 992 unrelated healthy subjects by Sequenom MassARRAY. The results showed that, compared with the reference CC genotype, the TC+TT genotype of miR?149 was more highly associated with HCC [CC vs. TC+TT: Odds ratio (OR)=1.384, 95% confidence interval (CI)=1.013?1.892, P=0.041], and was also associated with an increased risk of hepatitis B virus (HBV)?associated HCC (CC vs. TC+TT: OR=1.453, 95% CI=1.034?2.042, P=0.031). However, no significant association between miRNA?608 rs4919510 and the risk of HCC/HBV?associated HCC was found. In addition, these two SNPs were shown not to be correlated with a range of clinical characteristics. The present study may provide an indicator for identification of the high risk of HCC in patients.
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Inhibiting ?-Amyloid-Associated Alzheimer's Pathogenesis In Vitro and In Vivo by a Multifunctional Dimeric Bis(12)-hupyridone Derived from Its Natural Analogue.
J. Mol. Neurosci.
PUBLISHED: 09-01-2014
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Fibrillar aggregates of ?-amyloid protein (A?) is the main constituent of senile plaques and considered to be one of the causative events in the pathogenesis of Alzheimer's disease (AD). Compounds that could inhibit the formation of A? fibrils and block A? fibrils-associated toxicity may have therapeutic potential to combat AD. Bis(12)-hupyridone (B12H) is a multifunctional homodimer derived from huperzine A, which is an anti-AD drug in China. In the current study, the inhibitory effect of B12H on the formation of A? fibrils and their associated toxicity was investigated both in vitro and in vivo. By using Thioflavin T fluorescence assay, we found that B12H (0.3-3 ?M) directly inhibited A? fibrils formation following co-incubation of B12H and A?1-40 at 37 °C for 6 days in vitro. However, huperzine A, at the same concentrations, did not show significant inhibitory effect on A?1-40 fibrils formation. Moreover, B12H markedly reduced A?1-40-induced cytotoxicity in cultured SH-SY5Y cells, as evidenced by the increase in cell viability, the decrease in lactate dehydrogenase release, and the reduction of apoptotic nuclei. Most importantly, B12H (0.2 and 0.4 mg/kg) reduced intracerebroventricular A?1-40 infusion-induced cognitive and memory impairments in rats, as evidenced by the decrease in escape latency and the increase in the spatial bias in Morris water maze test along with increasing choline acetyltransferase activity and decreasing acetylcholinesterase activity. Collectively, our study provided novel sights into the potential application of B12H in AD treatment.
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Diblock Copolymers of Polyethylene Glycol and a Polymethacrylamide with Side-Chains Containing Twin Ortho Ester Rings: Synthesis, Characterization, and Evaluation as Potential pH-Responsive Micelles.
Macromol Biosci
PUBLISHED: 08-30-2014
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The diblock copolymer, PEG-b-PMEA, was synthesized by reversible-addition fragmentation chain transfer polymerization (RAFT). The PMEA block contained a polymethacrylamide backbone and twin ortho ester rings in the side-chains. At neutral pH, PEG-b-PMEA self-assembled to form stable micelles. At pH 5, the twin ortho ester rings were quickly hydrolyzed to completion in 12?h, and releasing nearly 70% of the encapsulated Nile Red dye. The PEG-b-PMEA micelles were completely nontoxic to cultured cells as determined by the MTT assay. Paclitaxel (PTX)-loaded micelles showed toxicity toward lung cancer cells comparable to that of the free PTX at equivalent doses. These results suggest that the PEG-b-PMEA micelles could be useful nano-carriers for pH-responsive delivery of poorly soluble anticancer drugs.
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Automatic Segmentation and Quantitative Analysis of White Matter Hyperintensities on FLAIR Images Using Trimmed-Likelihood Estimator.
Acad Radiol
PUBLISHED: 08-28-2014
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Quantitative analysis of white matter hyperintensities (WMHs) on fluid-attenuated inversion recovery (FLAIR) images provides information for disease tracking, therapeutic efficacy assessment, and cognitive science research. This study developed an automatic segmentation method to detect and quantify WMHs on FLAIR images. This study aims to assess the accuracy and reproducibility of the proposed method.
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[Diagnostic efficiency of decline rate of signal intensity and apparent diffusion coefficient with different b values for differentiating benign and malignant breast lesions on diffusion-weighted 3.0T magnetic resonance imaging].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-27-2014
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To investigate the diagnostic efficiency of decline rate of signal intensity and apparent diffusion coefficient with different b values for differentiating benign and malignant breast lesions on diffusion-weighted 3.0 T magnetic resonance imaging.
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Making proteomics data accessible and reusable: Current state of proteomics databases and repositories.
Proteomics
PUBLISHED: 08-26-2014
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Compared to other data intensive disciplines such as genomics, public deposition and storage of mass spectrometry (MS)-based proteomics data is still less developed due to, among other reasons, the inherent complexity of the data and the variety of data types and experimental workflows. In order to address this need several public repositories for MS proteomics experiments have been developed, each with different purposes in mind. The most established resources are the Global Proteome Machine Database (GPMDB), PeptideAtlas and the PRoteomics IDEntifications (PRIDE) database. Additionally, there are other useful (in many cases recently developed) resources such as ProteomicsDB, MassIVE, Chorus, MaxQB, PASSEL, MOPED and the Human Proteinpedia. In addition, the ProteomeXchange consortium has been recently developed for enabling a better integration of public repositories and the coordinated sharing of proteomics information, maximizing its benefit to the scientific community. Here, we will review each of the major proteomics resources independently and some tools that enable the integration, mining and reuse of the data. We will also discuss some of the major challenges and current pitfalls in the integration and sharing of the data. This article is protected by copyright. All rights reserved.
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Etiology, clinical features and management of acute recurrent pancreatitis.
J Dig Dis
PUBLISHED: 08-21-2014
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To study the etiology and clinical features of acute recurrent pancreatitis (ARP) and to determine its optimal management and outcomes.
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Differential effect of calcium-activated potassium and chloride channels on rat basilar artery vasomotion.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 08-19-2014
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Spontaneous, rhythmical contractions, or vasomotion, can be recorded from cerebral vessels under both normal physiological and pathophysiological conditions. We investigated the cellular mechanisms underlying vasomotion in the cerebral basilar artery (BA) of Wistar rats. Pressure myograph video microscopy was used to study the changes in cerebral artery vessel diameter. The main results of this study were as follows: (1) The diameters of BA and middle cerebral artery (MCA) were 314.5±15.7 ?m (n=15) and 233.3±10.1 ?m (n=12) at 10 mmHg working pressure (P<0.05), respectively. Pressure-induced vasomotion occurred in BA (22/28, 78.6%), but not in MCA (4/31, 12.9%) from 0 to 70 mmHg working pressure. As is typical for vasomotion, the contractile phase of the response was more rapid than the relaxation phase; (2) The frequency of vasomotion response and the diameter were gradually increased in BA from 0 to 70 mmHg working pressure. The amplitude of the rhythmic contractions was relatively constant once stable conditions were achieved. The frequency of contractions was variable and the highest value was 16.7±4.7 (n=13) per 10 min at 60 mmHg working pressure; (3) The pressure-induced vasomotion of the isolated BA was attenuated by nifedipine, NFA, 18?-GA, TEA or in Ca(2+)-free medium. Nifedipine, NFA, 18?-GA or Ca(2+)-free medium not only dampened vasomotion, but also kept BA in relaxation state. In contrasts, TEA kept BA in contraction state. These results suggest that the pressure-induced vasomotion of the isolated BA results from an interaction between Ca(2+)-activated Cl(-) channels (CaCCs) currents and K(Ca) currents. We hypothesize that vasomotion of BA depends on the depolarizing of the vascular smooth muscle cells (VSMCs) to activate CaCCs. Depolarization in turn activates voltage-dependent Ca(2+) channels, synchronizing contractions of adjacent cells through influx of extracellular calcium and the flow of calcium through gap junctions. Subsequent calcium-induced calcium release from ryanodine-sensitive stores activates K(Ca) channels and hyperpolarizes VSMCs, which provides a negative feedback loop for regenerating the contractile cycle.
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[Expression of TFPI-2 gene and its promoter methylation in acute myeloid leukemia].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 08-19-2014
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The aim of this study was to detect the mRNA expression of tissue factor pathway inhibitor-2 ( TFPI-2) and its methylation in bone marrow mononuclear cells from acute myeloid leukemia (AML) patients and to explore its significance in AML. Bone marrow mononuclear cells were isolated from newly diagnosed AML patients (n = 33), complete remission AML patients (n = 19), relapsed/refractory AML patients (n = 12) and iron deficiency anemia patients (control group, n = 15). Expression of TFPI-2 mRNA was detected with real-time quantitative PCR (RT-PCR) and the methylation of CpG island in its promoter was detected with methylation-specific PCR (MSP). The results showed that the expression of TFPI-2 mRNA in newly diagnosed AML, complete remission AML and relapsed/refractory AML patients was much lower than that in the controls (P < 0.05). Furthermore, its expression in relapsed/refractory AML patients was lower than that in newly diagnosed AML patients (P = 0.006). Compared with complete remission AML patients, the expression of TFPI-2 mRNA in newly diagnosed AML patients was significantly reduced (P = 0.030). The percentage of TFPI-2 promoter methylation in AML patients was 64.63% (42/64). In newly diagnosed AML group, complete remission AML group and relapsed/refractory AML group,the percentages of TFPI-2 promoter methylation were 66.67% (22/33), 52.63% (10/19) and 83.33% (10/12) (P > 0.05), respectively. The optical density ratio of TFPI-2 mRNA expression was 0.165 (0.005-2.099) in methylated AML patients, and 0.597 (0.011-2.787) in unmethylated AML patients (P < 0.05). Methylation of TFPI-2 gene promoter was not detected in control patients. After 2 courses of chemotherapy, the level of TFPI-2 mRNA was much higher in the CR group than that in the non-CR group (P < 0.05). It is concluded that the down-regulation or silence of TFPI-2 gene potentially results from its promoter methylation, and the expression level of TFPI-2 and the methylation status of its promoter may be used as indicators of risk stratification and evaluation of disease progress.
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Automatic segmentation and volumetric quantification of white matter hyperintensities on fluid-attenuated inversion recovery images using the extreme value distribution.
Neuroradiology
PUBLISHED: 08-18-2014
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This study aims to develop an automatic segmentation framework on the basis of extreme value distribution (EVD) for the detection and volumetric quantification of white matter hyperintensities (WMHs) on fluid-attenuated inversion recovery (FLAIR) images.
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Antibacterial activities of nemonoxacin against clinical isolates of Staphylococcus aureus: an in vitro comparison with three fluoroquinolones.
World J. Microbiol. Biotechnol.
PUBLISHED: 08-18-2014
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In comparison with ciprofloxacin, levofloxacin and moxifloxacin, antimicrobial activity of nemonoxacin against ciprofloxacin-susceptible/-resistant methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) was determined with the availability to select resistant mutants evaluated. Minimum inhibitory concentrations and mutant prevention concentrations of quinolones were determined by agar dilution method, that concentrated bacterial cells were spread onto Mueller-Hinton agar plates containing antibacterials at different concentrations. Selection index (SI) was calculated. Minimum inhibitory concentration and mutant prevention concentration of nemonoxacin were 0.063 and 0.25 ?g/mL for ciprofloxacin-susceptible MSSA and those were 0.5 and 4.0 ?g/mL for ciprofloxacin-resistant MSSA, lower than observations of three fluoroquinolones distinctly. SI of nemonoxacin and moxifloxacin were similar, with narrower mutant selective window than levofloxacin and ciprofloxacin. Minimum inhibitory concentration and mutant prevention concentration of nemonoxacin were 0.25 and 2.0 ?g/mL for ciprofloxacin-susceptible MRSA, which were 0.5 and 16.0 ?g/mL for ciprofloxacin-resistant MRSA. Values were lower than those determined from fluoroquinolones. Nemonoxacin presents good antimicrobial activity against clinical isolates of S. aureus, especially for ciprofloxacin-resistant strains. But stepwise mutant accumulation of ciprofloxacin-resistant MRSA can be hardly inhibited by nemonoxacin with pharmacokinetic parameters considered.
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Automatic segmentation of white matter lesions on magnetic resonance images of the brain by using an outlier detection strategy.
Magn Reson Imaging
PUBLISHED: 08-15-2014
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White matter lesions (WMLs) are commonly observed on the magnetic resonance (MR) images of normal elderly in association with vascular risk factors, such as hypertension or stroke. An accurate WML detection provides significant information for disease tracking, therapy evaluation, and normal aging research. In this article, we present an unsupervised WML segmentation method that uses Gaussian mixture model to describe the intensity distribution of the normal brain tissues and detects the WMLs as outliers to the normal brain tissue model based on extreme value theory. The detection of WMLs is performed by comparing the probability distribution function of a one-sided normal distribution and a Gumbel distribution, which is a specific extreme value distribution. The performance of the automatic segmentation is validated on synthetic and clinical MR images with regard to different imaging sequences and lesion loads. Results indicate that the segmentation method has a favorable accuracy competitive with other state-of-the-art WML segmentation methods.
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MicroRNA-145: a potent tumour suppressor that regulates multiple cellular pathways.
J. Cell. Mol. Med.
PUBLISHED: 08-15-2014
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MicroRNAs are endogenous, small (18-25 nucleotides) non-coding RNAs, which regulate genes expression by directly binding to the 3'-untranslated regions of the target messenger RNAs. Emerging evidence shows that alteration of microRNAs is involved in cancer development. MicroRNA-145 is commonly down-regulated in many types of cancer, regulating various cellular processes, such as the cell cycle, proliferation, apoptosis and invasion, by targeting multiple oncogenes. This review aims to summarize the recent published literature on the role of microRNA-145 in regulating tumourigenesis and progression, and explore its potential for cancer diagnosis, prognosis and treatment.
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Allogeneic Articular Chondrocyte Transplantation Downregulates Interleukin 8 Gene Expression in the Degenerating Rabbit Intervertebral Disk In Vivo.
Am J Phys Med Rehabil
PUBLISHED: 08-14-2014
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The aim of this study was to investigate whether repopulating the degenerating intervertebral disk (IVD) with articular chondrocytes will decrease inflammation in the degenerating rabbit IVD.
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Oncogenic mutations are associated with histological subtypes but do not have an independent prognostic value in lung adenocarcinoma.
Onco Targets Ther
PUBLISHED: 08-13-2014
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Lung adenocarcinomas have diverse genetic and morphological backgrounds and are usually classified according to their distinct oncogenic mutations (or so-called driver mutations) and histological subtypes (the de novo classification proposed by the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society [IASLC/ATS/ERS]). Although both these classifications are essential for personalized treatment, their integrated clinical effect remains unclear. Therefore, we analyzed 981 lung adenocarcinomas to detect the potential correlation and combined effect of oncogenic mutations and histological subtype on prognosis. Analysis for oncogenic mutations included the direct sequencing of EGFR, KRAS, HER2, BRAF, PIK3CA, ALK, and RET for oncogenic mutations/rearrangements, and a rereview of the IASLC/ATS/ERS classification was undertaken. Eligible tumors included 13 atypical adenomatous hyperplasia/adenocarcinoma in situ, 20 minimally invasive adenocarcinomas, 901 invasive adenocarcinomas, 44 invasive mucinous adenocarcinomas, and three other variants. The invasive mucinous adenocarcinomas had a lower prevalence of EGFR mutations but a higher prevalence of KRAS, ALK, and HER2 mutations than invasive adenocarcinomas. Smoking, a solid predominant pattern, and a mucinous component were independently associated with fewer EGFR mutations. The ALK rearrangements were more frequently observed in tumors with a minor mucinous component, while the KRAS mutations were more prevalent in smokers. In addition, 503 patients with stage I-IIIA tumors were analyzed for overall survival (OS) and relapse-free survival. The stage and histological pattern were independent predictors of relapse-free survival, and the pathological stage was the only independent predictor for the OS. Although patients with the EGFR mutations had better OS than those without the mutations, no oncogenic mutation was an independent predictor of survival. Oncogenic mutations were associated with the novel IASLC/ATS/ERS classification, which facilitates a morphology-based mutational analysis strategy. The combination of these two classifications might not increase the prognostic ability, but it provides essential information for personalized treatment.
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YAP inhibits squamous transdifferentiation of Lkb1-deficient lung adenocarcinoma through ZEB2-dependent DNp63 repression.
Nat Commun
PUBLISHED: 08-13-2014
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Whether the Hippo pathway contributes to cell lineage transition under pathological conditions, especially tumorigenesis, remains largely unknown. Here we show that YAP, the major effector of the Hippo pathway, displays a distinct activation pattern in lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC); YAP is initially activated by LKB1 loss in lung ADC, which upregulates ZEB2 expression and represses DNp63 transcription in a default manner. During transdifferentiation, YAP is inactivated, which in turn relieves ZEB2-mediated default repression of DNp63 and triggers squamous differentiation reprogramming. Disruption of the YAP barrier for phenotypic transition significantly accelerates squamous transdifferentiation, whereas constitutive YAP activation conversely inhibits this transition. More importantly, ectopic DNp63 expression rescues the inhibitory effect of YAP on squamous transdifferentiation. These findings have established YAP as an essential barrier for lung cancer cell fate conversion and provided a mechanism for regulating cancer plasticity, which might hold important implication for YAP-targeted therapies.
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S100A4 promotes liver fibrosis via activation of hepatic stellate cells.
J. Hepatol.
PUBLISHED: 08-08-2014
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S100A4 has been linked to fibrosis of several organs as a marker for fibroblasts. However, the role of S100A4 itself in fibrosis development has little been investigated. Herein, we determined whether S100A4 regulates liver fibrogenesis and examined its mechanism by focusing on activation of hepatic stellate cells (HSCs).
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Inhibitory effect of hydrogen sulfide on platelet aggregation and the underlying mechanisms.
J. Cardiovasc. Pharmacol.
PUBLISHED: 08-08-2014
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: H2S (hydrogen sulfide) possesses anti-inflammatory and antioxidant capabilities and offers cardiovascular protection. The effect of H2S on platelet function, however, has been less clear. Platelet activation is a key step in the initiation and development of atherothrombotic diseases. This study explored the effects and mechanisms of H2S on human platelet in vitro and under dyslipidemia conditions. This study indicated that the collagen-induced aggregation of washed human platelets, adenosine triphosphate release, and TXA2 formation were inhibited by NaHS incubation. Furthermore, NaHS significantly decreased intracellular calcium concentration in washed human platelets stimulated with collagen and inhibited collagen-induced c-PLA2, p38 MAPK, ERK, JNK, PLC-?2, and Akt phosphorylation. Finally, NaHS inhibited the aggregation of washed human platelets induced by oxidized low-density lipoprotein plus collagen. The level of plasma lipids and the collagen-induced rapid platelet aggregation in ApoE knockout mice were also significantly decreased by NaHS treatment. Our study shows that NaHS is able to inhibit platelet aggregation induced by collagen. The underlying mechanisms are related to NaHS-induced changes in various signaling pathways and [Ca]i in the platelets. The interaction of NaHS and platelets is also affected by lipid metabolism.
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Double charge ordering states and spin ordering state observed in a RFe2O4 system.
Sci Rep
PUBLISHED: 08-07-2014
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Charge, spin, and lattice degrees of orderings are of great interest in the layered quantum material RFe2O4 (R = Y, Er, Yb, Tm, and Lu) system. Recently many unique properties have been found using various experimental methods. However so far the nature of the two-dimensional (2D) charge ordering (CO) state is not clear and no observation of its fine structure in energy has been reported. Here we report unambiguous observation of double 2D CO states at relatively high temperature in a polycrystalline Er0.1Yb0.9Fe2O4 using Raman scattering. The energy gaps between the 3D and the double 2D states are 170 meV (41.2 THz) and 193 meV (46.6 THz), respectively. We also observed a spin ordering (SO) state at below 210 K with characteristic energy of 45 meV (10.7 THz). Our investigation experimentally identified new fine structures of quantum orders in the system, which also extends the capability of optical methods in investigating other layered quantum materials.
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Association between a variant in microRNA-646 and the susceptibility to hepatocellular carcinoma in a large-scale population.
ScientificWorldJournal
PUBLISHED: 08-07-2014
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Single-nucleotide polymorphisms in microRNAs play important roles in oncogenesis and cancer development. Objective. We aim to explore whether miR-646 rs6513497 is associated with the risk of hepatocellular carcinoma.
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Calculation of the Respiratory Modulation of the Photoplethysmogram (DPOP) Incorporating a Correction for Low Perfusion.
Anesthesiol Res Pract
PUBLISHED: 08-07-2014
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DPOP quantifies respiratory modulations in the photoplethysmogram. It has been proposed as a noninvasive surrogate for pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. The correlation between DPOP and PPV may degrade due to low perfusion effects. We implemented an automated DPOP algorithm with an optional correction for low perfusion. These two algorithm variants (DPOPa and DPOPb) were tested on data from 20 mechanically ventilated OR patients split into a benign "stable region" subset and a whole record "global set." Strong correlation was found between DPOP and PPV for both algorithms when applied to the stable data set: R = 0.83/0.85 for DPOPa/DPOPb. However, a marked improvement was found when applying the low perfusion correction to the global data set: R = 0.47/0.73 for DPOPa/DPOPb. Sensitivities, Specificities, and AUCs were 0.86, 0.70, and 0.88 for DPOPa/stable region; 0.89, 0.82, and 0.92 for DPOPb/stable region; 0.81, 0.61, and 0.73 for DPOPa/global region; 0.83, 0.76, and 0.86 for DPOPb/global region. An improvement was found in all results across both data sets when using the DPOPb algorithm. Further, DPOPb showed marked improvements, both in terms of its values, and correlation with PPV, for signals exhibiting low percent modulations.
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The effect of nC?? on tissue distribution of ibuprofen in Cyprinus carpio.
Sci. Total Environ.
PUBLISHED: 08-07-2014
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The potential transfer of fullerene aqueous suspension (nC??) associated contaminants in vivo is one of the most significant and currently not well-understood environmental risks. In this study, the carrier function of nC?? for ibuprofen (IBU) was examined through whole-body and tissue distribution determination of nC?? and IBU in Cyprinus carpio. The results showed that the presence of nC?? only slightly increased the whole-body burden of IBU, because the amount of soluble IBU far exceeds that of nC?? associated form of IBU; while the presence of nC?? activated the catalase activity and enhanced the lipid peroxidation in the liver, suggesting an obviously induced oxidative damage to fish. With the presence of nC??, the uptake of IBU in both gill and digestive tract tissues increased obviously: the uptake of IBU in the gill was mainly from the desorption of nC?? associated IBU, and that in the digestive tract was both from nC?? associated IBU and soluble IBU. On the contrary, the nC?? reduced IBU uptake in the brain, probably due to the high accumulation of nC?? which blocked the blood brain barrier. Moreover, there was no significant increase in the muscle, which implies that the soluble form should be the main source of IBU accumulation in the muscle. The carrier function of nC?? observed in the present study indicates the potential transportation of other contaminants and the subsequently enhanced environmental risks.
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Temperature dependence of dielectric and electromechanical properties of (K,Na)(Nb,Ta)O3 single crystal and corresponding domain structure evolution.
J Appl Phys
PUBLISHED: 07-30-2014
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Domain structures and their evolution with temperature in the [001] C oriented (K,Na)(Nb,Ta)O3 (KNNT) single crystal have been studied before and after poling by polarizing light microscopy. The results indicate that the KNNT crystal is difficult to be completely poled by the room temperature poling process. The domain structure is rather stable in the orthorhombic phase, but exhibits substantial changes near the phase transition temperatures T O-T and T C. Narrower stripe domains are formed during both the orthorhombic-tetragonal and tetragonal-cubic phase transition processes, no intermediate phases were found during the phase transitions. The temperature dependence of the dielectric and piezoelectric properties were measured, and the influence of domain structures on the dielectric and electromechanical properties were quantified.
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Higher TNF-?, IGF-1, and Leptin Levels are Found in Tasters than Non-Tasters.
Front Endocrinol (Lausanne)
PUBLISHED: 07-29-2014
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Taste perception is controlled by taste cells that are present in the tongue that produce and secrete various metabolic hormones. Recent studies have demonstrated that taste receptors in tongue, gut, and pancreas are associated with local hormone secretion. The aim of this study was to determine whether there is a link between taste sensitivity and levels of circulating metabolic hormones in humans and whether taste sensitivity is potentially related to peripheral metabolic regulation. Thirty-one subjects were recruited and separated into tasters and non-tasters based on their phenol thiocarbamide (PTC) bitter taste test results. Fasting plasma and saliva were collected and levels of hormones and cytokines were assayed. We observed significant differences in both hormone levels and hormone-body mass index (BMI) correlation between tasters and non-tasters. Tasters had higher plasma levels of leptin (p?=?0.05), tumor necrosis factor-? (TNF-?) (p?=?0.04), and insulin-like growth factor 1 (IGF-1) (p?=?0.03). There was also a trend toward increased IGF-1 levels in the saliva of tasters (p?=?0.06). We found a positive correlation between plasma levels of glucose and BMI (R?=?0.4999, p?=?0.04) exclusively in non-tasters. In contrast, plasma C-peptide levels were found to be positively correlated to BMI (R?=?0.5563, p?=?0.03) in tasters. Saliva TNF-? levels were negatively correlated with BMI in tasters (R?=?-0.5908, p?=?0.03). Our findings demonstrate that there are differences in circulating levels of leptin, TNF-?, and IGF-1 between tasters and non-tasters. These findings indicate that in addition to the regulation of food consumption, taste perception also appears to be tightly linked to circulating metabolic hormone levels. People with different taste sensitivity may respond differently to the nutrient stimulation. Further work investigating the link between taste perception and peripheral metabolic control could potentially lead to the development of novel therapies for obesity or Type 2 diabetes.
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Preventive effect of insect tea against reserpine-induced gastric ulcers in mice.
Exp Ther Med
PUBLISHED: 07-23-2014
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The aim of the present study was to determine the preventive effect of insect tea against reserpine-induced gastric ulcers in ICR mice. A high (800 mg/kg) dose of insect tea reduced the serum levels of the proinflammatory cytokines interleukin (IL)-6, IL-12, tumor necrosis factor (TNF)-? and interferon (IFN)-? compared with those in mice treated with a low (400 mg/kg) dose and the control mice. The serum levels of somatostatin (SS) and vasoactive intestinal peptide (VIP) in mice treated with insect tea were higher compared with those in the control mice; however, the serum levels of motilin (MOT) and substance P (SP) were lower in mice treated with insect tea than in the control mice. Gastric ulcer inhibitory rate of the insect tea treatment group of mice were much lower compared to the control mice, and the high concentration treated mice were similar to the ranitidine treated mice. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in mice treated with insect tea were higher compared with those in control mice, and similar to those in normal mice and ranitidine-treated mice. The nitric oxide (NO) and maleic dialdehyde (MDA) levels of mice treated with a high concentration of insect tea compared with the normal group were close. Using quantitative polymerase chain reaction (qPCR) assays, the present study revealed that insect tea significantly induced inflammation in the tissues of mice by downregulating the expression of nuclear factor ?-light-chain-enhancer of activated B cells (NF-?B), inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and upregulating the expression of nuclear factor of ? light polypeptide gene enhancer in B-cells inhibitor ? (I?B-?). These results suggest that insect tea is as effective at preventing gastric ulcers as the gastric ulcer drug, ranitidine and it can be used as medicine.
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Intravoxel incoherent motion diffusion-weighted MR imaging of breast cancer at 3.0 tesla: Comparison of different curve-fitting methods.
J Magn Reson Imaging
PUBLISHED: 07-21-2014
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To compare three different curve-fitting methods for intravoxel incoherent motion (IVIM) analysis in breast cancer.
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Meta-analysis of lobectomy, segmentectomy, and wedge resection for stage I non-small cell lung cancer.
J Surg Oncol
PUBLISHED: 07-21-2014
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Survival difference following lobectomy, segmentectomy, and wedge resection in stage I non-small cell lung cancer (NSCLC) and its subgroups remains undetermined.
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Epitaxial Seeded Growth of Rare-Earth Nanocrystals with Efficient 800?nm Near-Infrared to 1525?nm Short-Wavelength Infrared Downconversion Photoluminescence for In?Vivo Bioimaging.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-21-2014
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Novel ?-NaGdF4 /Na(Gd,Yb)F4 :Er/NaYF4 :Yb/NaNdF4 :Yb core/shell?1/shell?2/shell?3 (C/S1/S2/S3) multi-shell nanocrystals (NCs) have been synthesized and used as probes for in?vivo imaging. They can be excited by near-infrared (800?nm) radiation and emit short-wavelength infrared (SWIR, 1525?nm) radiation. Excitation at 800?nm falls into the "biological transparency window", which features low absorption by water and low heat generation and is considered to be the ideal excitation wavelength with the least impact on biological tissues. After coating with phospholipids, the water-soluble NCs showed good biocompatibility and low toxicity. With efficient SWIR emission at 1525?nm, the probe is detectable in tissues at depths of up to 18?mm with a low detection threshold concentration (5?nM for the stomach of nude mice and 100?nM for the stomach of SD rats). These results highlight the potential of the probe for the in?vivo monitoring of areas that are otherwise difficult to analyze.
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Annual nitric and nitrous oxide fluxes from Chinese subtropical plastic greenhouse and conventional vegetable cultivations.
Environ. Pollut.
PUBLISHED: 07-17-2014
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As intensive vegetable cultivation is rapidly expanding in China and elsewhere worldwide, its environmental consequences on nitrous oxide (N2O) and nitric oxide (NO) emissions deserve attention. We measured N2O and NO fluxes simultaneously for a full year from Chinese subtropical vegetable fields. Clearly, both N2O and NO emissions varied greatly in different vegetable crop seasons within a year, highlighting the importance of whole-year measurement for achieving temporally accurate annual direct emission factors. A revised "hole-in-the-pipe" model well described quantitative relationships between N2O plus NO fluxes and soil-specific conditions. Annual background N2O and NO emissions were 0.73-5.0 and 0.26-0.56 kg N ha(-1) yr(-1), respectively, for the vegetable cultivations. The farmers' fertilization practice increased N2O and NO emissions. Annual direct emission factors for greenhouse and conventional vegetable fields, respectively, were 1.1% and 1.9% for N2O, and 0.36% and 0.32% for NO, indicating there is a need to consider a differentiation of emission factors for managed vegetable cultivations.
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Racial/Ethnic Differences in Sleep Disturbances: The Multi-Ethnic Study of Atherosclerosis (MESA).
Sleep
PUBLISHED: 07-16-2014
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There is limited research on racial/ethnic variation in sleep disturbances. This study aimed to quantify the distributions of objectively measured sleep-disordered breathing (SDB), short sleep duration, poor sleep quality, and self-reported sleep disturbances (e.g., insomnia) across racial/ethnic groups.
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Highly Enantioselective Ring-Opening Reactions of Aziridine with Indole and Its Application in the Building of C3 -Halogenated-Pyrroloindolines.
Chemistry
PUBLISHED: 07-10-2014
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A magnesium-catalyzed asymmetric ring-opening reaction of aziridine with indole has been realized by employing commercially available chiral ligands. Both of the enantiomers of the ring-opening product could be obtained with good yields and a high level of enantioselectivity. The corresponding ring-opening product could be further transformed to various types of enantioenriched C3 -halogenated-pyrroloindolines.
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The PKARI?/AKAP10 signaling pathway is associated with prognosis of colorectal cancer.
J. Gastroenterol. Hepatol.
PUBLISHED: 06-28-2014
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The aim of this study was to investigate the role of PKA RI?/AKAP10 signaling pathway in colorectal cancer (CRC).
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Long non-coding RNAs in non-small cell lung cancer as biomarkers and therapeutic targets.
J. Cell. Mol. Med.
PUBLISHED: 06-19-2014
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Lung cancer-associated mortality is the most common cause of cancer death worldwide. Non-coding RNAs (ncRNAs), with no protein-coding ability, have multiple biological roles. Long non-coding RNAs (lncRNAs) are a recently characterized class of ncRNAs that are over 200 nucleotides in length. Many lncRNAs have the ability of facilitating or inhibiting the development and progression of tumours, including non-small cell lung cancer (NSCLC). Because of their fundamental roles in regulating gene expression, along with their involvement in the biological mechanisms underlying tumourigenesis, they are a promising class of tissue- and/or blood-based cancer biomarkers. In this review, we highlight the emerging roles of lncRNAs in NSCLC, and discuss their potential clinical applications as diagnostic and prognostic markers and as therapeutic targets.
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Indirect Effects of Radiation Induce Apoptosis and Neuroinflammation in Neuronal SH-SY5Y Cells.
Neurochem. Res.
PUBLISHED: 06-14-2014
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Recent studies have evaluated the role of direct radiation exposure in neurodegenerative disorders; however, association among indirect effects of radiation and neurodegenerative diseases remains rarely discussed. The objective of this study was to estimate the relative risk of neurodegeneration due to direct and indirect effects of radiation. (60)Co gamma ray was used as source of direct radiation whereas irradiated cell conditioned medium (ICCM) was used to mimic the indirect effect of radiation. To determine the potency of ICCM to inhibit neuronal cells survival colony forming assay was performed. The role of ICCM to induce apoptosis in neuronal SH-SY5Y cells was estimated by TUNEL assay and Annexin V/PI assay. Level of oxidative stress and the concentration of inflammatory cytokines after exposing to direct radiation and ICCM were evaluated by ELISA method. Expression of key apoptotic protein following direct and indirect radiation exposure was investigated by western blot technique. Experimental data manifest that ICCM account loss of cell survival and increase apoptotic induction in neuronal SH-SY5Y cells that was dependent on time and dose. Moreover, ICCM stimulate significant release of inflammatory cytokines i.e., tumor necrosis factor TNF-alpha (P < 0.01), Interleukin-1 (IL-1, P < 0.001), and Interleukin-6 (IL-6, P < 0.001) in neuronal SH-SY5Y cells and elevate the level of oxidative stress (MDA, P < 0.01). Up-regulation of key apoptotic protein expression i.e., Bax, Bid, cytochrome C, caspase-8 and caspase-3 confirms the toxicity of ICCM to neuronal cells. This study provides the evidence that indirect effect of radiation can be as much damaging to neuronal cells as direct radiation exposure can be. Hence, more focused research on estimation risks of indirect effect of radiation to CNS at molecular level may help to reduce the uncertainty about cure and cause of several neurodegenerative disorders.
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Challenges in Recruitment to a Randomized Controlled Study of Cardiovascular Disease Reduction in Sleep Apnea: An Analysis of Alternative Strategies.
Sleep
PUBLISHED: 06-07-2014
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A challenge in conducting randomized controlled trials of sleep apnea is the timely recruitment of participants to active and control arms. This study assesses the costs and efficiencies of alternative recruitment methods.
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Comparison of diagnostic value of a novel noninvasive coronary computed tomography angiography method versus standard coronary angiography for assessing fractional flow reserve.
Am. J. Cardiol.
PUBLISHED: 05-30-2014
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Noninvasive fractional flow reserve (FFR) from coronary computed tomography angiography (cCTA) correlates well with invasive FFR and substantially improves the detection of obstructive coronary artery disease. However, with current algorithms, computed tomography (CT)-based FFR is derived off-site in an involved time-consuming manner. We sought to investigate the diagnostic performance of a novel CT-based FFR algorithm, developed for time-efficient in-hospital evaluation of hemodynamically indeterminate coronary lesions. In a blinded fashion, CT-based FFR was assessed in 67 coronary lesions of 53 patients. Pressure guidewire-based FFR <0.80 served as the reference standard to define hemodynamically significant stenosis and assess the diagnostic performance of CT-based FFR compared with standard evaluation of cCTA (luminal diameter stenosis of ?50%). We recorded the time needed for derivation of CT-based FFR. On a per-lesion and per-patient basis, CT-based FFR resulted in a sensitivity of 85% and 94%, a specificity of 85% and 84%, a positive predictive value of 71% and 71%, and a negative predictive value of 93% and 97%, respectively. The area under the receiver operating characteristic curve on a per-lesion basis was significantly greater for CT-based FFR compared with standard evaluation of cCTA (0.92 vs 0.72, p = 0.0049). A similar trend, albeit not statistically significant, was observed on per-patient analysis (0.91 vs 0.78, p = 0.078). Mean total time for CT-based FFR was 37.5 ± 13.8 minutes. In conclusion, the CT-based FFR algorithm evaluated here outperforms standard evaluation of cCTA for the detection of hemodynamically significant stenoses while allowing on-site application within clinically viable time frames.
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Analysis of the molecular and clinicopathologic features of surgically resected lung adenocarcinoma in patients under 40 years old.
J Thorac Dis
PUBLISHED: 05-25-2014
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The youthful lung cancer may constitute an entity with distinct clinicopathologic characteristics and a controversial prognosis compared with the older counterpart. Whether the youthful lung cancer has the exclusively distinct molecular features has not been well investigated.
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MicroRNA-451 induces epithelial-mesenchymal transition in docetaxel-resistant lung adenocarcinoma cells by targeting proto-oncogene c-Myc.
Eur. J. Cancer
PUBLISHED: 05-09-2014
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Epithelial-mesenchymal transition (EMT) has been reported to play a significant role in tumour metastasis as well as chemoresistance. However, the molecular mechanisms involved in chemotherapy-induced EMT are still unclear. MicroRNA (miRNA) expression and functions have been reported to contribute to phenotypic features of tumour cells. To investigate the roles of miRNAs in chemotherapy-induced EMT, we established two docetaxel-resistant lung adenocarcinoma (LAD) cell models (SPC-A1/DTX and H1299/DTX), which display EMT-like properties and gain increased invasion or migration activity. MiR-451 was found to be significantly downregulated in docetaxel-resistant LAD cells, and re-expression of miR-451 could reverse EMT to mesenchymal-epithelial transition (MET) and inhibit invasion and metastasis of docetaxel-resistant LAD cells both in vitro and in vivo. The proto-oncogene c-Myc was identified as a direct and functional target of miR-451, and further researches confirmed that overexpression of c-Myc which induced extracellular-signal-regulated kinase (ERK)-dependent glycogen synthase kinase-3 beta (GSK-3?) inactivation and subsequent snail activation is essential for acquisition of EMT phenotype induced by loss of miR-451. Furthermore, c-Myc was significantly upregulated in docetaxel-non-responding LAD tissues in comparison with docetaxel-responding tissues, and its expression was inversely correlated with miR-451 expression. This study first reported the involvement of miR-451/c-Myc/ERK/GSK-3? signalling axis in the acquisition of EMT phenotype in docetaxel-resistant LAD cells, suggesting that re-expression of miR-451 or targeting c-Myc will be a potential strategy for the treatment of chemoresistant LAD patients.
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Functional characterization of myeloid-derived suppressor cell subpopulations during the development of experimental arthritis.
Eur. J. Immunol.
PUBLISHED: 05-01-2014
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Recent evidence indicates the existence of subpopulations of myeloid-derived suppressor cells (MDSCs) with distinct phenotypes and functions. Here, we characterized the role of MDSC subpopulations in the pathogenesis of autoimmune arthritis in a collagen-induced arthritis (CIA) mouse model. The splenic CD11b(+) Gr-1(+) MDSC population expanded in CIA mice, and these cells could be subdivided into polymorphonuclear (PMN) and mononuclear (MO) MDSC subpopulations based on Ly6C and Ly6G expression. During CIA, the proportion of splenic MO-MDSCs was increased in association with the severity of joint inflammation, while PMN-MDSCs were decreased. MO-MDSCs expressed higher levels of surface CD40 and CD86 protein, but lower levels of Il10, Tgfb1, Ccr5 and Cxcr2 mRNA. PMN-MDSCs exhibited a more potent capacity to suppress polyclonal T-cell proliferation in vitro, compared with MO-MDSCs. Moreover, the adoptive transfer of PMN-MDSCs, but not MO-MDSCs, decreased joint inflammation, accompanied by reduced levels of serum cytokine secretion and the frequencies of Th1 and Th17 cells in draining lymph nodes. These results suggest that there could be a shift from potently suppressive PMN-MDSCs to poorly suppressive MO-MDSCs during the development of experimental arthritis, which might reflect the failure of expanded MDSCs to suppress autoimmune arthritis. This article is protected by copyright. All rights reserved.
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A Systematic Assessment of the Association of Polysomnographic Indices with Blood Pressure: The Multi-Ethnic Study of Atherosclerosis (MESA).
Sleep
PUBLISHED: 05-01-2014
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Blood pressure (BP) may be adversely affected by a variety of sleep disturbances, including sleep fragmentation, hypoxemia, respiratory disturbances, and periodic limb movements. We aim to identify which polysomnography indices are most strongly and consistently associated with systolic and diastolic blood pressure (SBP, DBP) levels in a population-based sample.
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Increasing signal processing sophistication in the calculation of the respiratory modulation of the photoplethysmogram (DPOP).
J Clin Monit Comput
PUBLISHED: 04-18-2014
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DPOP (?POP or Delta-POP) is a non-invasive parameter which measures the strength of respiratory modulations present in the pulse oximetry photoplethysmogram (pleth) waveform. It has been proposed as a non-invasive surrogate parameter for pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. Many groups have reported on the DPOP parameter and its correlation with PPV using various semi-automated algorithmic implementations. The study reported here demonstrates the performance gains made by adding increasingly sophisticated signal processing components to a fully automated DPOP algorithm. A DPOP algorithm was coded and its performance systematically enhanced through a series of code module alterations and additions. Each algorithm iteration was tested on data from 20 mechanically ventilated OR patients. Correlation coefficients and ROC curve statistics were computed at each stage. For the purposes of the analysis we split the data into a manually selected 'stable' region subset of the data containing relatively noise free segments and a 'global' set incorporating the whole data record. Performance gains were measured in terms of correlation against PPV measurements in OR patients undergoing controlled mechanical ventilation. Through increasingly advanced pre-processing and post-processing enhancements to the algorithm, the correlation coefficient between DPOP and PPV improved from a baseline value of R = 0.347 to R = 0.852 for the stable data set, and, correspondingly, R = 0.225 to R = 0.728 for the more challenging global data set. Marked gains in algorithm performance are achievable for manually selected stable regions of the signals using relatively simple algorithm enhancements. Significant additional algorithm enhancements, including a correction for low perfusion values, were required before similar gains were realised for the more challenging global data set.
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Coronary CT angiography-derived fractional flow reserve correlated with invasive fractional flow reserve measurements - initial experience with a novel physician-driven algorithm.
Eur Radiol
PUBLISHED: 04-17-2014
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The present study aimed to determine the feasibility of a novel fractional flow reserve (FFR) algorithm based on coronary CT angiography (cCTA) that permits point-of-care assessment, without data transfer to core laboratories, for the evaluation of potentially ischemia-causing stenoses.
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Colistin and anti-Gram-positive bacterial agents against Acinetobacter baumannii.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 04-12-2014
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Acinetobacter baumannii has attained an alarming level of resistance to antibacterial drugs. Clinicians are now considering the use of older agents or unorthodox combinations of licensed drugs against multidrug-resistant strains to bridge the current treatment gap. We investigated the in vitro activities of combination treatments that included colistin with vancomycin, norvancomycin or linezolid against multidrug-resistant Acinetobacter baumannii.
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The improved blood-brain barrier permeability of endomorphin-1 using the cell-penetrating peptide synB3 with three different linkages.
Int J Pharm
PUBLISHED: 04-03-2014
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Endomorphins, although they have high analgesic activity and few undesirable side effects, are not in clinical use because of the blood-brain barrier (BBB). One promising solution is to use cell-penetrating peptides (CPPs). CPPs have the ability to translocate cell membranes and have been successfully applied for delivery of therapeutic molecules across the BBB. However, little is known about the transport efficiency of different conjugation strategies between cargo and CPPs. In this study, endomorphin-1 (EM-1) was conjugated with SynB3, an efficient CPP-carrier, via amide, maleimide and disulfide linkages. The delivery efficiency of three linkers was compared in terms of pharmacodynamics and in vitro metabolic stability. Near-infrared fluorescent and fluorescent microscopy experiments were applied to detect the brain uptake and distribution of CPP delivery qualitatively and quantitatively. After the most successful linkage was screened out, the further mechanisms were discussed. We concluded that compared with the other two linkages, the disulfide bond was the most efficient linkage to deliver EM-1 across the BBB and confirmed that it could be reduced at physiological conditions in the brain and release its active form. These findings indicate that for those who need to release a free drug in the brain and maintain activity, a disulfide bond might be the most efficient linkage across the BBB.
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Antimicrobial activities and membrane-active mechanism of CPF-C1 against multidrug-resistant bacteria, a novel antimicrobial peptide derived from skin secretions of the tetraploid frog Xenopus clivii.
J. Pept. Sci.
PUBLISHED: 04-03-2014
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Hospital-acquired infections caused by multidrug-resistant bacteria pose significant challenges for treatment, which necessitate the development of new antibiotics. Antimicrobial peptides are considered potential alternatives to conventional antibiotics. The skin of Anurans (frogs and toads) amphibians is an extraordinarily rich source of antimicrobial peptides. CPF-C1 is a typical cationic antimicrobial peptide that was originally isolated from the tetraploid frog Xenopus clivii. Our results showed that CPF-C1 has potent antimicrobial activity against both sensitive and multidrug-resistant bacteria. It disrupted the outer and inner membranes of bacterial cells. CPF-C1 induced both propidium iodide uptake into the bacterial cell and the leakage of calcein from large liposome vesicles, which suggests a mode of action that involves membrane disturbance. Scanning electron microscopy and transmission electron microscopy verified the morphologic changes of CPF-C1-treated bacterial cells and large liposome vesicles. The membrane-dependent mode of action signifies that the CPF-C1 peptide functions freely and without regard to conventional resistant mechanisms. Additionally, it is difficult for bacteria to develop resistance against CPF-C1 under this action mode. Other studies indicated that CPF-C1 had low cytotoxicity against mammalian cell. In conclusion, considering the increase in multidrug-resistant bacterial infections, CPF-C1 may offer a new strategy that can be considered a potential therapeutic agent for the treatment of diseases caused by multidrug-resistant bacteria. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.
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Selenite reduction by the obligate aerobic bacterium Comamonas testosteroni S44 isolated from a metal-contaminated soil.
BMC Microbiol.
PUBLISHED: 03-19-2014
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Selenium (Se) is an essential trace element in most organisms but has to be carefully handled since there is a thin line between beneficial and toxic concentrations. Many bacteria have the ability to reduce selenite (Se(IV)) and (or) selenate (Se(VI)) to red elemental selenium that is less toxic.
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Solubilization of 4,4'-dibromodiphenyl ether under combined TX-100 and cosolvents.
Environ Sci Pollut Res Int
PUBLISHED: 02-21-2014
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This paper is focused on the selection of cosolvents in the remediation of contaminated soils. The aim of this study was to investigate the combined effects of Triton X-100 (TX-100) and different cosolvents on the solubilization behavior of 4,4'-dibromodiphenyl ether (BDE-15) and the washing of BDE-15 from a contaminated soil. (1)H NMR spectroscopies were used to elucidate the interactions among TX-100, cosolvents, and BDE-15 in aqueous micellar solution. Results showed that the solubility of BDE-15 was enhanced by the observed synergism among TX-100, BDE-15, and cosolvents, and the TX-100/dimethyl sulfoxide (DMSO) system exhibited the best performance in the solubilization of BDE-15. Similar synergism was further evidenced in the washing of BDE-15 from a contaminated soil. With 10 % (v/v) DMSO and 6.4 mM TX-100 solution added, considerable synergistic effect was achieved in TX-100/DMSO system, leading to the highest removal efficiency (92.9 %) of BDE-15 from the soil, relative to that of 67.3 % with TX-100 alone at the same concentration.
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In vitro and in vivo anti-cancer activities of Kuding tea (Ilex kudingcha C.J. Tseng) against oral cancer.
Exp Ther Med
PUBLISHED: 02-13-2014
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Kuding tea (Ilex kudingcha C.J. Tseng) is drunk widely in China. The in vitro anticancer effects of Kuding tea were evaluated in TCA8113 human tongue carcinoma cells using a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. At a concentration of 200 ?g/ml, Kuding tea exhibited an inhibitory effect of 75% in TCA8113 cells, which was higher than that observed at concentrations of 100 and 50 ?g/ml (41 and 10% inhibition, respectively). Reverse transcription-polymerase chain reaction (RT-PCR) and western blot analyses of the apoptosis, inflammation and metastasis genes and proteins in Kuding tea-treated cancer cells were performed. Kuding tea significantly induced apoptosis in TCA8113 cancer cells (P<0.05) by upregulating Bax, caspase-3 and caspase-9 expression, and downregulating Bcl-2 expression. Expression of the NF-?B, iNOS and COX-2 genes that are associated with inflammation was significantly downregulated by Kuding tea, which demonstrated its anti-inflammatory properties. Kuding tea also exerted an anti-metastatic effect on cancer cells. This was demonstrated by the decreased expression of matrix metalloproteases (MMPs) and the increased expression of tissue inhibitors of metalloproteinases (TIMPs), and confirmed by the inhibition of the metastasis of U14 squamous cell carcinoma cells in imprinting control region (ICR) mice. The ICR mouse buccal mucosa cancer model was established by injecting the mice with U14 cells. Following injection, the wound at the injection site was topically treated with Kuding tea. It was observed that the tumor volumes for the group treated with Kuding tea were smaller than those from the control mice. Analysis of the sections of buccal mucosa cancer tissue demonstrated that the buccal mucosa cancer degrees of the Kuding tea-treated mice were weaker than that in the control mice. Similar results were observed in the lesion sections of the cervical lymph nodes. Based on these results, Kuding tea exhibited successful in vitro anticancer effects in TCA8113 cells and in vivo buccal mucosa cancer preventive activity.
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An unusual fat-containing presacral tumor in an elderly patient.
Case Rep Radiol
PUBLISHED: 02-06-2014
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The authors present a case of a presacral myelolipoma diagnosed in an 84-year-old male patient with longstanding pelvic pain and past medical history of bladder cancer. Pelvic computed tomography (CT) revealed a well-encapsulated and lobulated presacral mass, with mixed fat and soft-tissue attenuation. Magnetic resonance (MR) imaging provided further confirmation of macroscopic intralesional fat and excluded either adjacent bone invasion or bladder cancer recurrence. A presacral myelolipoma was suspected based on imaging findings, with liposarcoma and teratoma having also been considered for the differential diagnosis. The histological confirmation of the tumor was only attained postoperatively. This case report alerts to the possible presacral location of myelolipomas, which should be considered for every fat-containing lesion detected in this region. The main clinical, imaging, and differential diagnoses of this entity are reviewed in this paper.
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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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