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Find video protocols related to scientific articles indexed in Pubmed.
Determination of four flavorings in infant formula by solid-phase extraction and gas chromatography-tandem mass spectrometry.
J. Agric. Food Chem.
PUBLISHED: 10-31-2014
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Increasing attention has been focused on the artificial flavorings added in foods, especially those for infants and children. For the first time, a sensitive and efficient analytical method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the simultaneous identification and quantification of four flavoring agents (vanillin, methylvanillin, ethylvanillin, and coumarin) in infant formula samples. The flavorings in samples were extracted with methanol/water (v/v, 1:1), cleaned up by solid-phase extraction, and determined by GC-MS/MS in selected reaction monitoring (SRM) mode. Both isotope-labeled internal standards and matrix-matched calibration solutions were used to correct the matrix effects. The limit of quantification (LOQ) was calculated as 10 times the standard deviation, and it was 10.0 ?g kg (-1) for vanillin, methylvanillin, ethylvanillin, and coumarin. The average recoveries were in the range of 82.8-107.5% with relative standard deviations (RSDs) below 8.9% measured at three concentration levels (10, 50, and 100 ?g kg(-1)). The proposed method is suitable for the sensitive and accurate simultaneous determination of four flavoring agents in infant formula samples and also provided potential use for reference in terms of real analysis of other foods.
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Synthesis, solution-processed thin film transistors and solid solutions of silylethynylated diazatetracenes.
Chem. Commun. (Camb.)
PUBLISHED: 07-22-2014
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Silylethynylated diazatetracenes were synthesized in a more efficient way and applied as n-type semiconductors in solution-processed thin film transistors with an electron mobility of 0.65 cm(2) V(-1) s(-1). Co-crystallization of these diazatetracenes with silylethynylated tetracene resulted in solid solutions, which exhibited interesting electrical and optical properties.
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Sulforaphane Ameliorates Neurobehavioral Deficits and Protects the Brain From Amyloid ? Deposits and Peroxidation in Mice With Alzheimer-Like Lesions.
Am J Alzheimers Dis Other Demen
PUBLISHED: 07-16-2014
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Alzheimer's disease (AD) is a common neurodegenerative disease in the elderly individuals and its effective therapies are still unavailable. This study was designed to investigate the neuroprotection of sulforaphane (SFN) in AD-lesion mice induced by combined administration of d-galactose and aluminium. Results showed that SFN ameliorated spatial cognitive impairment and locomotor activity decrease in Morris water maze and open field test, respectively. And attenuated numbers of amyloid ? (A?) plaques in both hippocampus and cerebral cortex of AD-lesion mice were detected by immunohistochemistry. According to spectrophotometry and quantitative reverse-transcriptase polymerase chain reaction results, a significant increase in carbonyl group level and obvious decreases in both activity and messenger RNA expression of glutathione peroxidase were found in brain of AD-lesion mice compared with control, but not in SFN-treated AD-lesion mice. In conclusion, SFN ameliorates neurobehavioral deficits and protects the brain from A? deposits and peroxidation in mice with Alzheimer-like lesions, suggesting SFN is likely a potential phytochemical to be used in AD therapeutics.
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Self-assembled monolayers of cyclohexyl-terminated phosphonic acids as a general dielectric surface for high-performance organic thin-film transistors.
Adv. Mater. Weinheim
PUBLISHED: 06-25-2014
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A novel self-assembled monolayer (SAM) on AlOy /TiOx is terminated with cyclohexyl groups, an unprecedented terminal group for all kinds of SAMs. The SAM-modified AlOy /TiOx functions as a general dielectric, enabling organic thin-film transistors with a field-effect mobility higher than 5 cm(2) V(-1) s(-1) for both holes and electrons, good air stability with low operating voltage, and general applicability to solution-processed and vacuum-deposited n-type and p-type organic semiconductors.
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Heteroatom-bridged tetraphenylenes: synthesis, structures, and properties.
Org. Lett.
PUBLISHED: 06-09-2014
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Novel oxygen-, nitrogen-, sulfur-, and selenium-bridged tetraphenylenes were prepared from known tetraphenylene derivatives. Structures of these compounds were unambiguously confirmed by X-ray crystallographic analyses. Photophysical and electrochemical investigations of these heteroatom-bridged tetraphenylenes suggested their potential applications as electronic materials.
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Restriction of Intramolecular Motions: The General Mechanism behind Aggregation-Induced Emission.
Chemistry
PUBLISHED: 06-04-2014
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Aggregation-induced emission (AIE) has been harnessed in many systems through the principle of restriction of intramolecular rotations (RIR) based on mechanistic understanding from archetypal AIE molecules such as tetraphenylethene (TPE). However, as the family of AIE-active molecules grows, the RIR model cannot fully explain some AIE phenomena. Here, we report a broadening of the AIE mechanism through analysis of 10,10',11,11'-tetrahydro-5,5'-bidibenzo[a,d][7]annulenylidene (THBDBA), and 5,5'-bidibenzo[a,d][7]annulenylidene (BDBA). Analyses of the computational QM/MM model reveal that the novel mechanism behind the AIE of THBDBA and BDBA is the restriction of intramolecular vibration (RIV). A more generalized mechanistic understanding of AIE results by combining RIR and RIV into the principle of restriction of intramolecular motions (RIM).
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Improvement of ventilation-induced lung injury in a rodent model by inhibition of inhibitory ?B kinase.
J Trauma Acute Care Surg
PUBLISHED: 05-24-2014
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Inhibition of nuclear factor ?B (NF-?B) activation is a well-know strategy to ameliorate ventilation-induced lung injury (VILI). Inhibitory ?B kinase (IKK) plays a key role in the regulation of NF-?B activation. In this study, we determined whether inhibition of IKK by an IKK inhibitor exerts lung protection in a rat model of VILI.
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A novel, in vivo, indoor method to preserve rice black-streaked dwarf virus in small brown planthopper using wheat seedling as a bridge host.
J. Virol. Methods
PUBLISHED: 04-30-2014
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Rice black-streaked dwarf virus (RBSDV) naturally infects Gramineae plants through small brown planthopper (SBPH) as a vector. However, RBSDV cannot be transmitted to the SBPH offspring through transovarian transmission. Wheat plant, an important intermediate host in winter, is essential for the completion of the annual cycle of RBSDV in farm ecosystem. We developed a novel, in vivo, indoor method to preserve RBSDV in SBPH using wheat seedling as a bridge host. The temperature range of 23-27°C was initially selected to rear the insects and plants. Before initiating the scheme cycle, viruliferous SBPH was obtained by feeding the virus-free 1st to 2nd instar nymphs with RBSDV-infected rice plants. Four to six RBSDV-infected SBPH were placed per plant to inoculate wheat seedlings at two-to-four leaf stages. After 48 h of inoculation, the viruliferous SBPH were removed. Five mated, newly emerged virus-free SBPH females were then transferred onto each inoculated plant and allowed to lay eggs for 48 h. The newly hatched SBPH were raised on wheat seedlings until the 2nd instar nymph stage, and then transferred onto healthy rice seedlings for further development until 5th instar nymphs or adults. These newly obtained viruliferous SBPH can be used for inoculating new wheat seedlings in the succeeding maintenance cycles, or for further experiments. We discovered that the incubation period of RBSDV in wheat seedlings synchronized with the gestation period of SBPH eggs at four to six inoculated viruliferous SBPH per plant and lasted for approximately seven days. In addition, this period was optimal for enhancing the SBPH infection ratio because SBPH nymphs can only acquire the virus after they hatch. The RBSDV infection ratio of the SBPHs acquired through this method consistently exceeded 50%.
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Galangin dampens mice lipopolysaccharide-induced acute lung injury.
Inflammation
PUBLISHED: 04-19-2014
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Galangin, an active ingredient of Alpinia galangal, has been shown to possess anti-inflammatory and antioxidant activities. Inflammation and oxidative stress are known to play vital effect in the pathogenesis of acute lung injury (ALI). In this study, we determined whether galangin exerts lung protection in lipopolysaccharide (LPS)-induced ALI. Male BALB/c mice were randomized to receive galangin or vehicle intraperitoneal injection 3 h after LPS challenge. Samples were harvested 24 h post LPS administration. Galangin administration decreased biochemical parameters of oxidative stress and inflammation, and improved oxygenation and lung edema in a dose-dependent manner. These protective effects of galangin were associated with inhibition of nuclear factor (NF)-?B and upregulation of heme oxygenase (HO)-1. Galangin reduces LPS-induced ALI by inhibition of inflammation and oxidative stress.
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Heptagon-embedded pentacene: synthesis, structures, and thin-film transistors of dibenzo[d,d']benzo[1,2-a:4,5-a']dicycloheptenes.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 03-20-2014
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This study presents a new class of conjugated polycyclic molecules that contain seven-membered rings, detailing their synthesis, crystal structures and semiconductor properties. These molecules have a nearly flat C6-C7-C6-C7-C6 polycyclic framework with a p-quinodimethane core. With field-effect mobilities of up to 0.76?cm(2) V(-1) s(-1) as measured from solution-processed thin-film transistors, these molecules are alternatives to the well-studied pentacene analogues for applications in organic electronic devices.
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Ten years of N-heteropentacenes as semiconductors for organic thin-film transistors.
Adv. Mater. Weinheim
PUBLISHED: 03-02-2014
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Introducing N atoms to the pentacene backbone leads to N-heteropentacenes, whose properties can be tuned by changing the number, position and valence state of N atoms in the pentacene backbone. With a rapid development in recent years, N-heteropentacenes and their derivatives have arisen as a new family of organic semiconductors with high performance in organic thin-film transistors (OTFTs). This article reviews the research efforts of developing N-heteropentacenes into organic semiconductors starting from 2003 with emphasis on the work of the author's group since 2009. The structure-property relationship and design rationale are highlighted based on an overview of reported organic semiconductors of N-heteropentacenes.
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Massively parallel patterning of complex 2D and 3D functional polymer brushes by polymer pen lithography.
ACS Appl Mater Interfaces
PUBLISHED: 01-17-2014
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We report the first demonstration of centimeter-area serial patterning of complex 2D and 3D functional polymer brushes by high-throughput polymer pen lithography. Arbitrary 2D and 3D structures of poly(glycidyl methacrylate) (PGMA) brushes are fabricated over areas as large as 2 cm × 1 cm, with a remarkable throughput being 3 orders of magnitudes higher than the state-of-the-arts. Patterned PGMA brushes are further employed as resist for fabricating Au micro/nanostructures and hard molds for the subsequent replica molding of soft stamps. On the other hand, these 2D and 3D PGMA brushes are also utilized as robust and versatile platforms for the immobilization of bioactive molecules to form 2D and 3D patterned DNA oligonucleotide and protein chips. Therefore, this low-cost, yet high-throughput "bench-top" serial fabrication method can be readily applied to a wide range of fields including micro/nanofabrication, optics and electronics, smart surfaces, and biorelated studies.
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Quantitative determination of scattering mechanism in large-area graphene on conventional and SAM-functionalized substrates at room temperature.
Nanoscale
PUBLISHED: 05-20-2013
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In this letter, the different scattering mechanisms of triphenylene-derived graphene on conventional SiO2/Si substrates and octadecyltrimethoxysilane (OTMS) self-assembled monolayer (SAM) functionalized SiO2/Si substrates were systematically studied at room temperature. In comparison with the devices on conventional SiO2/Si substrates, triphenylene-derived GFETs with OTMS-SAM modified SiO2/Si substrate exhibit the marked carrier-density-dependent field-effect mobility. Quantitative analyses reveal that at ambient temperature, the predominant scattering sources affect the carrier mean free path for graphene devices on bare SiO2 substrates and for those on OTMS passivated SiO2 substrates are charged impurity induced long-range scattering (~5.34 × 10(11) cm(-2) in carrier density) and resonant scattering (short-range scattering ~9.77 × 10(10) cm(-2) carrier in density), respectively. Our findings elucidate the underlying dominant factors for achieving significantly improved device performance of GFETs at room temperature.
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Inhaled neutrophil elastase inhibitor reduces oleic acid-induced acute lung injury in rats.
Pulm Pharmacol Ther
PUBLISHED: 12-05-2011
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Neutrophil elastases (NE) play an important role in the pathogenesis of acute lung injury (ALI). NE activities are significantly increased in serums and lungs of patients or animals with ALI. Intravenous infusion (IV) of Sivelestat, an NE inhibitor, can reduce ALI. Through inhalation, drugs reach lungs directly and in high concentration. We hypothesized that inhaled Sivelestat would alleviate oleic acid (OA)-induced ALI in rats.
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The position of nitrogen in N-heteropentacenes matters.
Adv. Mater. Weinheim
PUBLISHED: 09-30-2011
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An exploratory study on novel silylethynylated N-heteropentacenes, which have their N atoms on the terminal rings of the pentacene backbone, is reported. This study leads to both p- and n-channel organic thin-film transistors with high field-effect mobility and also reveals that the position of the N atoms plays an important role in tuning the structures and properties of organic semiconductors based on N-heteropentacenes.
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High hole mobility of 1,2-bis[4-(diphenylamino)biphenyl-4-yl]-1,2-diphenylethene in field effect transistor.
Chem. Commun. (Camb.)
PUBLISHED: 05-20-2011
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Triphenylamine-functionalized tetraphenylethene shows aggregation-induced emission feature with unity solid-state fluorescence efficiency. Its amorphous film can function in a p-type FET device with field effect mobility up to 2.6 × 10(-3) cm(2)/Vs.
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Molecular characterization and expression analysis of a gene encoding for farnesyl diphosphate synthase from Euphorbia pekinensis Rupr.
Mol. Biol. Rep.
PUBLISHED: 05-14-2011
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The root of Euphorbia pekinensis as a traditional herbal medicine has been recorded in Chinese pharmacopoeias for the treatment of oedema, gonorrhea, migraine and wart cures. In this work, we reported on the cDNA cloning and characterization of a novel farnesyl diphosphate synthase (FPS) from E. pekinensis. The full-length cDNA named EpFPS (Genbank Accession Number FJ755465) contained 1431 bp with an open reading frame of 1029 bp encoding a polypeptie of 342 amino acids. The deduced amino acid sequence of the EpFPS named EpFPS exhibited a high homology with other plant FPSs, and contained five conserved domains. Phylogenetic analysis showed that EpFPS belonged to the plant FPS group. Southern blot analysis revealed that there exists a small FPS gene family in E. pekinensis. Expression pattern analysis revealed that EpFPS expressed strongly in root, weak in leaf and stem. In callus, expression of EpFPS gene and biosynthesis of triterpenoids were strongly induced by Methyl jasmonate and slightly induced by Salicylic acid. Functional complementation of EpFPS in an ergosterol auxotrophic yeast strain indicated that the cloned cDNA encoded a functional farnesyl diphosphate synthase.
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Amycolatopsis endophytica sp. nov., a novel endophytic actinomycete isolated from oil-seed plant Jatropha curcas L.
Antonie Van Leeuwenhoek
PUBLISHED: 02-21-2011
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A novel actinomycete, designated KLBMP 1221(T), was isolated from the surface-sterilized seeds of an oil-seed plant Jatropha curcas L. collected from Sichuan Province, south-west China and was characterized taxonomically by using a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequence showed that this strain formed a distinct phyletic line within the radiation of the genus Amycolatopsis. The 16S rRNA gene sequence similarity indicated that strain KLBMP 1221(T) was most closely related to Amycolatopsis eurytherma NT202(T) (98.9%), Amycolatopsis tucumanensis ABO(T) (98.8%), Amycolatopsis thermoflava N1165(T) (98.6%) and Amycolatopsis methanolica IMSNU 20055(T) (98.5%). Strain KLBMP 1221(T) had morphological and chemotaxonomic properties that were consistent with its classification in the genus Amycolatopsis. However, DNA-DNA relatedness data and phenotypic differences clearly distinguished the isolate from its closest relatives. Based on the combined genotypic and phenotypic evidence, it is proposed that strain KLBMP 1221(T) be classified as representative of a novel species for which the name Amycolatopsis endophytica sp. nov. is proposed. The type strain is KLBMP 1221(T) (= KCTC 19776(T) = CCTCC AA 2010003(T)).
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Nocardia endophytica sp. nov., an endophytic actinomycete isolated from the oil-seed plant Jatropha curcas L.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 09-03-2010
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A novel actinomycete, designated strain KLBMP 1256(T), was isolated from a surface-sterilized stem of the oil-seed plant Jatropha curcas L. collected from Sichuan Province, south-west China, and was characterized to determine its taxonomic position. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the isolate was closely related to members of the genus Nocardia in the family Nocardiaceae, being most closely related to Nocardia callitridis CAP 290(T) (98.4 % similarity) and Nocardia nova JCM 6044(T) (97.5 %). Levels of 16S rRNA gene sequence similarity between strain KLBMP 1256(T) and the type strains of other recognized species of the genus Nocardia were less than 97 %. Chemotaxonomic data supported the affiliation of the new isolate to the genus Nocardia. However, the novel strain could be distinguished from its closest phylogenetic neighbour, N. callitridis CAP 290(T), by a range of phenotypic properties. The combination of low DNA-DNA relatedness values and phenotypic differences from N. callitridis CAP 290(T) indicated that strain KLBMP 1256(T) represents a novel species of the genus Nocardia, for which the name Nocardia endophytica sp. nov. is proposed. The type strain is KLBMP 1256(T) (?= KCTC 19777(T) ?= CCTCC AA 2010004(T)).
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N-heteroquinones: quadruple weak hydrogen bonds and n-channel transistors.
Chem. Commun. (Camb.)
PUBLISHED: 03-05-2010
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This study demonstrates that the easily synthesized N-heteroquinones, having unusual quadruple weak hydrogen bonds of a DDAA-AADD pattern, can function as n-type organic semiconductors in OTFTs with high electron mobility.
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[The Clinical Analysis of 21 Patients with Lymphoepithelioma-like Carcinoma after Operation.].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 10-12-2009
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Lung lymphoepithelioma-like carcinoma is a rare subtype of large cell carcinomas of the lung. The aim of this study is to retrospectively analyze the clinical characteristics, surgical methods, laboratory inspection, chemotherapy, radiotherapy and prognosis of LELC.
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Benzenoid and quinonoid nitrogen-containing heteropentacenes.
Chemistry
PUBLISHED: 03-06-2009
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Benzenoid or quinonoid-that is the question? In connection with the debate on the structure of dihydro-5,7,12,14-tetraazapentacene, both benzenoid and quinonoid nitrogen-containing heteropentacenes were successfully isolated and investigated (see picture). This report presents an exploratory study of the molecular and electronic structures, molecular packing, and semiconductor properties of the two compounds. These findings may lead to useful implications for the interesting ladder polymers.
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Disruption of the M80-Fe ligation stimulates the translocation of cytochrome c to the cytoplasm and nucleus in nonapoptotic cells.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-05-2009
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Native cytochrome c (cyt c) has a compact tertiary structure with a hexacoordinated heme iron and functions in electron transport in mitochondria and apoptosis in the cytoplasm. However, the possibility that protein modifications confer additional functions to cyt c has not been explored. Disruption of methionine 80 (M80)-Fe ligation of cyt c under nitrative stress has been reported. To model this alteration and determine if it confers new properties to cyt c, a cyt c mutant (M80A) was constitutively expressed in cells. M80A-cyt c has increased peroxidase activity and is spontaneously released from mitochondria, translocating to the cytoplasm and nucleus in the absence of apoptosis. Moreover, M80A models endogenously nitrated cyt c because nitration of WT-cyt c is associated with its translocation to the cytoplasm and nucleus. Further, M80A cyt c may up-regulate protective responses to nitrative stress. Our findings raise the possibility that endogenous protein modifications that disrupt the M80-Fe ligation (such as tyrosine nitration) stimulate nuclear translocation and confer new functions to cyt c in nonapoptotic cells.
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Photoresponsive nanoscale columnar transistors.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-12-2009
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This study reports a general methodology for making stable high-performance photosensitive field effect transistors (FET) from self-assembled columns of polycyclic aromatic hydrocarbons by using single-walled carbon nanotubes (SWNTs) as point contacts. In particular, the molecules used in this work are liquid crystalline materials of tetra(dodecyloxy)hexabenzocoronenes (HBCs) that are able to self-organize into columnar nanostructures with a diameter similar to that of SWNTs and then form nanoscale columnar transistors. To rule out potential artifacts, 2 different structural approaches were used to construct devices. One approach is to coat thin films of HBCs onto the devices with the SWNT-metal junctions protected by hydrogensilsesquioxane resin (HSQ), and the other is to place a droplet of HBC exactly on the nanogaps of SWNT electrodes. Both types of devices showed typical FET behaviors, indicating that SWNT-molecule-SWNT nanojunctions are responsible for the electrical characteristics of the devices. After thermally annealing the devices, HBC molecules assembled into columnar structures and formed more efficacious transistors with increased current modulation and higher gate efficiency. More interestingly, when the devices were exposed to visible light, photocurrents with an on/off ratio of >3 orders of magnitude were observed. This study demonstrates that stimuli-responsive nanoscale transistors have the potential applications in ultrasensitive devices for environmental sensing and solar energy harvesting.
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Ambipolar organic semiconductors from electron-accepting cyclopenta-fused anthracene.
Chem. Commun. (Camb.)
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Reported here are a new group of cyclopent[hi]aceanthrylene derivatives, which have a cyclopentadiene moiety to accept electrons and thus function as ambipolar organic semiconductors in thin film transistors.
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Highly electron-deficient hexaazapentacenes and their dihydro precursors.
Org. Lett.
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Novel silylethynylated N-heteropentacenes that have three adjacent pyrazine rings at the center of a pentacene backbone are reported. These hexaazapentacenes exhibit a record low energy level of lowest unoccupied molecular orbital (LUMO) for N-heteropentacenes and thus are able to oxidize dihydroanthracene to anthracene. Their synthetic precursors are the corresponding dihydrohexaazapentacenes, which exhibit interesting H-bonding.
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Curved polycyclic aromatic molecules that are ?-isoelectronic to hexabenzocoronene.
J. Am. Chem. Soc.
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Reported here are two types of curved ?-molecules that are ?-isoelectronic to planar hexabenzocoronene (HBC) but are forced out of planarity either by an embedded seven-membered ring or by atom crowding at the fjord region. Embedding a heptagon in HBC leads to a novel saddle-shaped molecule 1, whose ?-backbone is slightly less curved than the previously reported [7]circulene in terms of the average Gauss curvature, but surprisingly much more rigid than [7]circulene. Overcrowded fjord regions in novel derivatives of hexabenzoperylene (HBP) 2a,b lead to both chiral twisted and antifolded conformers. The successful synthesis of 1 and 2a,b is related to introducing alkoxyl groups to unprecedented positions of hexaphenylbenzenes. It is found that the red twisted isomer of 2b isomerizes at elevated temperature to the yellow anti-folded conformer. This finding along with the study on the thermodynamics and kinetics of the thermal isomerization has improved the early understandings on the conformation of HBP. In the crystals, 1 lacks ?-? interactions between neighboring molecules, while twisted-2a exhibits both face-to-face and edge-to-face ?-? interactions. Twisted-2b is found to function as a p-type semiconductor in thin film transistors, but the thin films of 1 appear insulating presumably due to lacking ?-? interactions. By exploring three different types of curvatures in 1 and the two isomers of 2b, this study has revealed that the curvature of ?-face plays a role in determining the frontier molecular orbital energy levels and ?-? interactions and thus needs to be considered when one designs new organic semiconductors.
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High-mobility group box 1 induces calcineurin-mediated cell hypertrophy in neonatal rat ventricular myocytes.
Mediators Inflamm.
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Cardiac hypertrophy is an independent predictor of cardiovascular morbidity and mortality. In recent years, evidences suggest that high-mobility group box 1 (HMGB1) protein, an inflammatory cytokine, participates in cardiac remodeling; however, the involvement of HMGB1 in the pathogenesis of cardiac hypertrophy remains unknown. The aim of this study was to investigate whether HMGB1 is sufficient to induce cardiomyocyte hypertrophy and to identify the possible mechanisms underlying the hypertrophic response. Cardiomyocytes isolated from 1-day-old Sprague-Dawley rats were treated with recombinant HMGB1, at concentrations ranging from 50?ng/mL to 200?ng/mL. After 24 hours, cardiomyocytes were processed for the evaluation of atrial natriuretic peptide (ANP) and calcineurin A expression. Western blot and real-time RT-PCR was used to detect protein and mRNA expression levels, respectively. The activity of calcineurin was also evaluated using a biochemical enzyme assay. HMGB1 induced cardiomyocyte hypertrophy, characterized by enhanced expression of ANP, and increased protein synthesis. Meanwhile, increased calcineurin activity and calcineurin A protein expression were observed in cardiomyocytes preconditioned with HMGB1. Furthermore, cyclosporin A pretreatment partially inhibited the HMGB1-induced cardiomyocyte hypertrophy. Our findings suggest that HMGB1 leads to cardiac hypertrophy, at least in part through activating calcineurin.
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Polymer pen lithography using dual-elastomer tip arrays.
Small
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Dual-elastomer tip arrays are developed as a simple and cost-effective approach to significantly improve the uniformity and precision of polymer pen lithography (PPL). Both experiment and mechanical simulation demonstrate that the hard-apex, soft-base tip structure of the dual-elastomer tip array leads to precise control of feature size and reduced variation among different tips over large areas through fine control of the tip deformation. The dual-elastomer tip array is believed to be readily applied to fabricate nano- and microstructures for fundamental study and applications such as bioassays, sensors, optical and electronic devices.
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[Estimating total nitrogen content in wetland vegetation based on measured reflectance spectra].
Guang Pu Xue Yu Guang Pu Fen Xi
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More and more urban wetlands have been supplied with reclaimed water. And monitoring the growth condition of large-area wetland vegetation is playing a very important role in wetland restoration and reconstruction. Recently, remote sensing technology has become an important tool for vegetation growth monitoring. The South Wetland in the Olympic Park, a typical wetland using reused water, was selected as the research area. The leaf reflectance spectra and were acquired for the main wetland plants reed (Phragmites australis) and cattail (Typha angustifolia) with an ASD FieldSpec 3 spectrometer (350 2 500 nm). The total nitrogen (TN) content of leaf samples was determined by Kjeldahl method subsequently. The research established univariate models involving simple ratio spectral index (SR) model and normalized difference spectral index (ND) model, as well as multivariate models including stepwise multiple linear regression (SMLR) model and partial least squares regression (PLSR) model. Moreover, the accuracy of all the models was tested through cross-validated coefficient of determination (R2(CV)) and cross-validated root mean square error (RMSE(CV)). The results showed that (1) comparing different types of wetland plants, the accuracy of all established prediction models using Phragmites australis reflectance spectra was higher than that using Typha angustifolia reflectance spectra. (2) compared with univariate techniques, multivariate regressions improved the estimation of TN concentration in leaves. (3) among the various investigated models, the accuracy of PLSR model was the highest (R2(CV) = 0.80, RMSE(CV) = 0.24). PLSR provided the most useful explorative tool for unraveling the relationship between spectral reflectance and TN consistence of leaves. The result would not only provide a scientific basis for remote sensing retrieval of biochemical variables of wetland vegetation, but also provide a strong scientific basis for the monitoring and management of urban wetlands using recycled water.
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[Diagnostic efficacy of an ultrasound quantitative method in a rat model of experimental liver fibrosis].
Zhonghua Gan Zang Bing Za Zhi
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To evaluate the efficacy of an ultrasound-based quantitative method to diagnose liver fibrosis using a rat model. Ultrasonography was performed on the livers of 90 Sprague-Dawley rats with or without thioacetamide-induced fibrosis. The liver capsule thickness and 13 texture parameters of gray level co-occurrence matrix were extracted from the standard sonograms. After sacrifice, severity of liver fibrosis (S0-S4 classification) was diagnosed by histopathology. Analysis of variance and correlation statistical tests were used to analyze the differences between groups and determine the relationships between each of the 14 quantitative ultrasound index points and the histological results, respectively. Discriminant analysis models were developed for quantitative diagnosis of liver fibrosis, and the leave-one-case-out method was used to verify the efficiency of models. All 14 indices were significantly correlated with the histological stages of fibrosis (P less than 0.05). The accuracy of the discriminant model for S0, S1, S2, S3 and S4 was 83.3%, 84.2%, 70.0%, 50.0% and 88.2%, respectively. In addition, 73.3% of cross-validated rats were accurately classified. Grouping S0 as no fibrosis, S1 as mild fibrosis, S2 with S3 as moderate to severe fibrosis and S4 as early cirrhosis increased the accuracy of the discriminant model for these four groups (respectively, 91.7%, 84.2%, 69.0% and 88.2%) and allowed for 78.9% of cross-validated rats to be correctly identified. Ultrasonography combined with texture analysis was a novel and accurate method to diagnose liver fibrosis in a rat model; further studies may provide insights into its applicability for quantitating liver fibrosis in other animal models or in clinic.
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Hydrogen-bonded dihydrotetraazapentacenes.
Org. Lett.
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Three new members of N-heteropentacenes explored herein have adjacent pyrazine and dihydropyrazine rings at one end of the pentacene backbone. Interesting findings from this study include self-complementary N-H···N H-bonds in the solid state, solvent-dependent UV-vis absorption caused by H-bonding, and new p-type organic semiconductors with field effect mobility up to 0.7 cm(2) V(-1) s(-1).
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What is Visualize?

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

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

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