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Find video protocols related to scientific articles indexed in Pubmed.
Direct phase-sensitive identification of a d-form factor density wave in underdoped cuprates.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-02-2014
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The identity of the fundamental broken symmetry (if any) in the underdoped cuprates is unresolved. However, evidence has been accumulating that this state may be an unconventional density wave. Here we carry out site-specific measurements within each CuO2 unit cell, segregating the results into three separate electronic structure images containing only the Cu sites [Cu(r)] and only the x/y axis O sites [Ox(r) and O(y)(r)]. Phase-resolved Fourier analysis reveals directly that the modulations in the O(x)(r) and O(y)(r) sublattice images consistently exhibit a relative phase of ?. We confirm this discovery on two highly distinct cuprate compounds, ruling out tunnel matrix-element and materials-specific systematics. These observations demonstrate by direct sublattice phase-resolved visualization that the density wave found in underdoped cuprates consists of modulations of the intraunit-cell states that exhibit a predominantly d-symmetry form factor.
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Direct spectroscopic evidence for phase competition between the pseudogap and superconductivity in Bi2Sr2CaCu2O8+?
Nat Mater
PUBLISHED: 02-19-2014
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In the high-temperature (Tc) cuprate superconductors, a growing body of evidence suggests that the pseudogap phase, existing below the pseudogap temperature T(?), is characterized by some broken electronic symmetries distinct from those associated with superconductivity. In particular, recent scattering experiments have suggested that charge ordering competes with superconductivity. However, no direct link of an interplay between the two phases has been identified from the important low-energy excitations. Here, we report an antagonistic singularity at Tc in the spectral weight of Bi2Sr2CaCu2O8+? as compelling evidence for phase competition, which persists up to a high hole concentration p ~ 0.22. Comparison with theoretical calculations confirms that the singularity is a signature of competition between the order parameters for the pseudogap and superconductivity. The observation of the spectroscopic singularity at finite temperatures over a wide doping range provides new insights into the nature of the competitive interplay between the two orders and the complex phase diagram near the pseudogap critical point.
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Doping dependence of low-energy quasiparticle excitations in superconducting Bi2212.
Nanoscale Res Lett
PUBLISHED: 07-17-2013
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The doping-dependent evolution of $d$-wave superconducting state is studied from the perspective of the angle-resolved photoemission spectra of a high-$T_c$ cuprate, Bi$_2$Sr$_2$CaCu$_2$O$_{8+delta}$ (Bi2212). The anisotropic evolution of the energy gap for Bogoliubov quasiparticles is parametrized by critical temperature and superfluid density. The renormalization of nodal quasiparticles is evaluated in terms of mass enhancement spectra. These quantities shed light on the strong coupling nature of electron pairing and the impact of forward elastic or inelastic scatterings. We suggest that the quasiparticle excitations in the superconducting cuprates are profoundly affected by doping-dependent screening.
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Integrating Pathways of Parkinsons Disease in a Molecular Interaction Map.
Mol. Neurobiol.
PUBLISHED: 04-15-2013
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Parkinsons disease (PD) is a major neurodegenerative chronic disease, most likely caused by a complex interplay of genetic and environmental factors. Information on various aspects of PD pathogenesis is rapidly increasing and needs to be efficiently organized, so that the resulting data is available for exploration and analysis. Here we introduce a computationally tractable, comprehensive molecular interaction map of PD. This map integrates pathways implicated in PD pathogenesis such as synaptic and mitochondrial dysfunction, impaired protein degradation, alpha-synuclein pathobiology and neuroinflammation. We also present bioinformatics tools for the analysis, enrichment and annotation of the map, allowing the research community to open new avenues in PD research. The PD map is accessible at http://minerva.uni.lu/pd_map .
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Deposition in Chiba prefecture, Japan, of Fukushima Daiichi Nuclear Power Plant fallout.
Health Phys
PUBLISHED: 01-01-2013
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Radioactivity from the Fukushima Daiichi Nuclear Power Plant (F-1NPP) accident in deposition samples has been monitored at the National Institute of Radiological Sciences (NIRS) in Chiba Prefecture, Japan, located about 220 km south-southwest of the F-1NPP. Sampling was carried out from 15 March 2011, two to three times a day for 10 d and then once a day until 22 April 2011. Gamma-ray spectrometry of fallout deposition samples revealed the presence of (131)I, (132)I, (132)Te, (134)Cs, and (137)Cs. The largest deposition was observed during 7:00-16:00 on 21 March. The estimated total deposition densities at NIRS were 1.40 × 10(5) Bq m(-2) for (131)I, 4.12 × 10(4) Bq m(-2) for (132)Te, 1.45 × 10(4) Bq m(-2) for (134)Cs, and 1.48 × 10(4) Bq m(-2) for (137)Cs (corrected to 11 March 2011). The obtained densities of (134)Cs and (137)Cs were also supported by the accumulated amount of (134)Cs and (137)Cs in soil near the deposition sampling site. For the vertical profile of those radionuclides in soil at NIRS, about 94% of the total deposition was distributed in the top 10 mm depth on 26 April 2011.
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[Determination of vedaprofen in livestock products and seafoods by liquid chromatography-tandem mass spectrometry].
Shokuhin Eiseigaku Zasshi
PUBLISHED: 12-28-2011
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A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the trace residue determination of vedaprofen (VPF) in livestock products and seafoods. VPF was extracted from each sample with acidified acetone, and the crude extract was re-extracted with ethyl acetate and NaCl solution. Clean-up was performed using a weak anion exchange cartridge (Bond Elut DEA). The LC separation was performed on a C18 column using acetonitrile-0.0025 mol/L formic acid (3 : 2) as the mobile phase and MS was run in the negative ion electrospray ionization mode. The calibration curve was linear in the range of 0.001-0.1 µg/mL VPF. The mean recoveries from equine muscle, cattle muscle, cattle liver, cattle fat, salmon, eel, corbicula, milk, egg and buckwheat honey were 72-94%, and the relative standard deviations (RSDs) were 1.1-2.0%. Limits of quantitation (LOQs) ranged from 0.001 to 0.007 µg/g.
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[Analytical method of cereulide in processed cereal-based foods and milk powder by LC-MS/MS].
Shokuhin Eiseigaku Zasshi
PUBLISHED: 12-28-2011
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An LC-MS/MS method for analysis of cereulide, an emetic toxin produced by Bacillus cereus, was developed. Cereulide was extracted from samples, fried rice, pan-fried noodles, red bean paste and baby formula, with methanol and purified using Oasis HLB cartridges. LC separation was performed on a C18 column with a mixture of formic acid solution and methanol containing ammonium formate as a mobile phase, and the mass spectrometer was operated in the positive electrospray ionization mode. Performance evaluation showed that trueness was higher than 70% and repeatability and reproducibility were within 10%. The limits of quantification were lower than 1 µg/kg.
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Oxidized phospholipid, 1-palmitoyl-2-(9-oxo-nonanoyl)-glycerophosphocholine (PON-GPC), produced in the lung due to cigarette smoking, impairs immune function in macrophages.
Lung
PUBLISHED: 09-25-2011
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Pulmonary innate immunity is impaired in cigarette smokers, because the abundant oxidants present in cigarette smoke (CS) cause injury to lung cells. Pulmonary surfactant is a unique material that is important roles in reducing surface tension in the lung and defending against invading pathogens. Oxidants reportedly cleave surfactant phospholipids, resulting in the production of oxidized phospholipids, such as 1-palmitoyl-2-(9-oxo-nonanoyl)-glycerophosphocholine (PON-GPC). Although oxidation of surfactant lipids is thought to be involved in the pathogenesis of smoking-related lung disease, there are no reports on the effect of oxidized surfactant lipid on the immune function of macrophages. We hypothesized that cigarette smoking elevates PON-GPC levels in the lung, and that PON-GPC impairs the innate immune function of macrophages.
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Determination of residual fluoroquinolones in honey by liquid chromatography using metal chelate affinity chromatography.
J AOAC Int
PUBLISHED: 09-17-2011
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A new analytical method for the simultaneous determination of seven fluoroquinolones, namely, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, orbifloxacin, sarafloxacin, and difloxacin, especially in dark-colored honey, has been developed. Fluoroquinolone antibiotics were extracted from samples with MacIlvaine buffer solution (pH 4.0) containing EDTA disodium salt dihydrate. The extracts were treated with both a polymeric cartridge and a metal chelate affinity column preloaded with ferric ion (Fe3+). LC separation with fluorescence detection was performed at 40 degrees C using an Inertsil ODS-4 analytical column (150 x 4.6 mm, 3 microm). The mobile phase was composed of 20 mM/L citrate buffer solution (pH 3.1)-acetonitrile mixture (70 + 30, v/v) containing 1 mM/L sodium dodecyl sulfate. Lomefloxacin was used as an internal standard. The developed method was validated according to the criteria of European Commission Decision 2002/657/EC. Decision limits and detection capabilities were below 2.9 and 4.4 microg/kg, respectively.
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Determination of Cr(III) and Cr(VI) at sub-ppb levels in water with solid-phase extraction/metal furnace atomic absorption spectrometry.
Anal Sci
PUBLISHED: 10-19-2010
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A simple method using solid-phase extraction combined with metal furnace atomic absorption spectrometry was developed for the determination of Cr(III) and Cr(VI) at sub-ppb levels in water. A 500-ml water sample was adjusted to pH 3 with nitric acid and then passed through an iminodiacetate extraction disk placed on a cation-exchange extraction disk at a flow rate of 20-40 ml min(-1) for concentrating Cr(III). The filtrate was adjusted to pH 10 with aqueous ammonia and then passed through an anion-exchange extraction disk at a flow rate of 2 ml min(-1) for concentrating Cr(VI). The Cr(III) and Cr(VI) collected were eluted with 40 ml of 3 mol l(-1) nitric acid for Cr(III) and 40 ml of 1 g l(-1) diphenylcarbazide solution for Cr(VI). Each eluate was diluted to 50 ml with deionized water and injected into a U-type tungsten board on the metal furnace. The calibration curves of Cr(III) and Cr(VI) showed good linearity in the range of 0.1-0.5 ng. The detection limits corresponding to three times the standard deviation (n = 5) of blank values were 8.1 pg for both Cr(III) and Cr(VI). The analytical value of total Cr (Cr(III) + Cr(VI)) in certified reference material of river water (JSAC 0302-3) was in good agreement with the reference value. The recovery test for 0.50 µg (1.00 µg l(-1)) of Cr(III) and Cr(VI) added to 500 ml of the water samples showed sufficient values (98.1-106%), except for river water sampled downstream due to relatively higher COD(Mn) value. The relative standard deviations (n = 5) were less than 5% for both Cr(III) and Cr(VI).
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Decoupling of receptor and downstream signals in the Akt pathway by its low-pass filter characteristics.
Sci Signal
PUBLISHED: 07-29-2010
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In cellular signal transduction, the information in an external stimulus is encoded in temporal patterns in the activities of signaling molecules; for example, pulses of a stimulus may produce an increasing response or may produce pulsatile responses in the signaling molecules. Here, we show how the Akt pathway, which is involved in cell growth, specifically transmits temporal information contained in upstream signals to downstream effectors. We modeled the epidermal growth factor (EGF)-dependent Akt pathway in PC12 cells on the basis of experimental results. We obtained counterintuitive results indicating that the sizes of the peak amplitudes of receptor and downstream effector phosphorylation were decoupled; weak, sustained EGF receptor (EGFR) phosphorylation, rather than strong, transient phosphorylation, strongly induced phosphorylation of the ribosomal protein S6, a molecule downstream of Akt. Using frequency response analysis, we found that a three-component Akt pathway exhibited the property of a low-pass filter and that this property could explain decoupling of the peak amplitudes of receptor phosphorylation and that of downstream effectors. Furthermore, we found that lapatinib, an EGFR inhibitor used as an anticancer drug, converted strong, transient Akt phosphorylation into weak, sustained Akt phosphorylation, and, because of the low-pass filter characteristics of the Akt pathway, this led to stronger S6 phosphorylation than occurred in the absence of the inhibitor. Thus, an EGFR inhibitor can potentially act as a downstream activator of some effectors.
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Four-year surveillance for ochratoxin a and fumonisins in retail foods in Japan.
J. Food Prot.
PUBLISHED: 02-06-2010
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Between 2004 and 2007 we examined foods from Japanese retail shops for contamination with ochratoxin A (OTA) and fumonisins B(1), B(2), and B(3). A total of 1,358 samples of 27 different products were examined for OTA, and 831 samples of 16 different products were examined for fumonisins. The limits of quantification ranged from 0.01 to 0.5 microg/kg for OTA and 2 to 10 microg/kg for the fumonisins. OTA was detected in amounts higher than limits of quantification in wheat flour, pasta, oatmeal, rye, buckwheat flour and dried buckwheat noodles, raisins, wine, beer, coffee beans and coffee products, chocolate, cocoa, and coriander. OTA was found in more than 90% of the samples of instant coffee and cocoa, and the highest concentration of OTA, 12.5 microg/kg, was detected in raisins. The concentration of OTA in oatmeal, rye, raisins, wine, and roasted coffee beans varied remarkably from year to year. Fumonisins were detected in frozen and canned corn, popcorn grain, corn grits, cornflakes, corn soups, corn snacks, beer, soybeans, millet, and asparagus. The highest concentrations of fumonisins B(1), B(2), and B(3) were detected in corn grits (1,670, 597, and 281 microg/kg, respectively). All of the samples of corn grits were contaminated with fumonisins, and more than 80% of the samples of popcorn grain and corn snacks contained fumonisins. OTA and fumonisins were detected in several food products in Japan; however, although Japan has not set regulatory levels for these mycotoxins, their concentrations were relatively low.
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Development of a novel immunoaffinity column for aflatoxin analysis using an organic solvent-tolerant monoclonal antibody.
J. Agric. Food Chem.
PUBLISHED: 09-12-2009
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An organic solvent-tolerant monoclonal antibody specific to aflatoxins B(1), B(2), G(1), G(2), and M(1) (AFB(1), AFB(2), AFG(1), AFG(2), and AFM(1)) was prepared. In an indirect competitive enzyme-linked immunosorbent assay, the half maximal inhibitory concentration (IC(50)) values were 1.9, 2.1, 2.1, 2.4, and 2.8 ng/mL for AFB(1), AFB(2), AFG(1), AFG(2), and AFM(1), respectively. Antibody reactivity was retained at 40% methanol concentration or at acetonitrile concentrations up to 40%. An immunoaffinity column (IAC) was prepared using agarose gel beads with bound antibody. The IAC retained the tested AFs that were 89, 90, 95, 90, and 89% for AFB(1), AFB(2), AFG(1), AFG(2), and AFM(1) at 20% acetonitrile concentrations or that were 81, 87, 79, and 83% for AFB(1), AFB(2), AFG(1), and AFG(2) at 60% methanol concentrations. Roasted peanuts and seven kinds of spices were spiked with 8.0, 1.0, 6.0, and 1.0 ng for AFB(1), AFB(2), AFG(1), and AFG(2) per 1 g sample and extracted with 90% acetonitrile. The roasted peanuts and cayenne pepper out of the spices were also extracted with 70% methanol. The extracts were diluted 5-fold with phosphate-buffered saline and applied to the IAC. The spiked aflatoxins were recovered with satisfactory rates: 78 (RSD, 2.1%) to 127% (RSD, 1.7%). The developed IAC was used for the analysis of aflatoxins in naturally contaminated samples of roasted peanuts and cayenne pepper. The newly developed IAC showed substantially organic solvent tolerance at the concentration that could not be used for existing IACs, and the column showed good ability to clean up samples for food analysis.
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LC-MS/MS coupled with immunoaffinity extraction for determination of estrone, 17beta-estradiol and estrone 3-sulfate in human plasma.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 07-09-2009
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Determination of estrogens in plasma is important in evaluation of effects of some anticancer drugs, such as aromatase inhibitors. However, as reported previously, high performance liquid chromatography-radio immunoassay (HPLC-RIA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) with chemical derivatization require complicated sample preparation. In this study, a highly sensitive and simple method for determination of estrone (E1), 17beta-estradiol (E2) and estrone 3-sulfate (E1S) in human plasma has been developed. Following diethylether extraction from plasma, analytes were purified by immunosorbents and then determined by LC-MS/MS using electrospray ionization (ESI). Immunosorbents were prepared by immobilization of specific antibodies raised against each analyte onto solid support. Use of selective immunosorbents in sample preparation removed interference in plasma samples that would cause ionization suppression, and markedly improved the sensitivity of LC-MS/MS for these analytes, without derivatization. Calibration curves of each analyte showed good linearity and reproducibility over the range of 0.05-50pg/injection for E1, 0.2-50pg/injection for E2 and 0.05-300pg/injection for E1S, respectively. The mean values of lower limits of quantification (LLOQ) in human plasma corrected by recovery of deuterated estrogens (internal standard, I.S.) were 0.1892pg/mL for E1, 0.7064pg/mL for E2 and 0.3333pg/mL for E1S, respectively. These LLOQ values were comparable to those previous reported using HPLC-RIA and LC-MS/MS. Using this method, the normal levels of three estrogens in healthy female plasma (n=5) were determined. The mean values of E1, E2 and E1S were 38.0pg/mL (range 24.8-53.0), 34.3pg/mL (22.6-46.6) and 786pg/mL (163-2080), respectively. The immunoaffinity LC-MS/MS described here allows sensitive and accurate quantification of E1, E2 and E1S without laborious sample preparation.
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[Determination of bicozamycin in livestock products and seafoods by liquid chromatography-tandem mass spectrometry].
Shokuhin Eiseigaku Zasshi
PUBLISHED: 05-14-2009
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A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for trace residue determination of bicozamycin (BZM) in livestock products and seafoods. BZM was extracted from a sample with acetonitrile-water (4 : 1), followed by a two-stage SPE enrichment and cleanup. The first stage involved a styrene-divinylbenzene copolymer cartridge (GL-Pak PLS-2), and the second stage involved a divinylbenzene-N-vinylpyrrolidone copolymer cartridge (Oasis HLB). The LC separation was performed on a C18 column using 0.01% formic acid-methanol (8 : 2) as the mobile phase and MS detection with negative ion electrospray ionization. The mean recoveries from swine muscle, liver, yellowtail, and milk fortified at the minimum residue limit (MRL) levels and 0.01 microg/g were >70%, and the relative standard deviations (RSDs) were <20%. Limits of quantitation (LOQs) ranged from 0.002 to 0.005 microg/g.
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Molecular cloning of t(2;7)(p24.3;p14.2), a novel chromosomal translocation in myelodysplastic syndrome-derived acute myeloid leukemia.
J. Hum. Genet.
PUBLISHED: 05-01-2009
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In this study, we report the molecular structure of the breakpoint region in a new chromosomal translocation, t(2;7)(p24.3;p14.2), in a case of acute myeloid leukemia transformed from myelodysplastic syndrome (MDS). An extensive fluorescence in situ hybridization (FISH) analysis showed that NAG (2p24.3) and ELMO1 (7p14.2) were involved at the breakpoints of t(2;7)(p24.3;p14.2). Furthermore, we detected a novel chimeric transcript consisting of NAG and ELMO1. Interestingly, this transcript encoded a truncated molecular form of 3ELMO1 as the result of a frameshift caused by the chromosomal translocation. Although this study does not provide direct evidence that a defect in NAG-ELMO1 plays a role in the pathogenesis or the leukemic change in MDS, it does suggest that defects in NAG-ELMO1 potentially contributed to the leukemic progression in this case.
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Phase competition in trisected superconducting dome.
Proc. Natl. Acad. Sci. U.S.A.
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A detailed phenomenology of low energy excitations is a crucial starting point for microscopic understanding of complex materials, such as the cuprate high-temperature superconductors. Because of its unique momentum-space discrimination, angle-resolved photoemission spectroscopy (ARPES) is ideally suited for this task in the cuprates, where emergent phases, particularly superconductivity and the pseudogap, have anisotropic gap structure in momentum space. We present a comprehensive doping- and temperature-dependence ARPES study of spectral gaps in Bi(2)Sr(2)CaCu(2)O(8+?), covering much of the superconducting portion of the phase diagram. In the ground state, abrupt changes in near-nodal gap phenomenology give spectroscopic evidence for two potential quantum critical points, p = 0.19 for the pseudogap phase and p = 0.076 for another competing phase. Temperature dependence reveals that the pseudogap is not static below T(c) and exists p > 0.19 at higher temperatures. Our data imply a revised phase diagram that reconciles conflicting reports about the endpoint of the pseudogap in the literature, incorporates phase competition between the superconducting gap and pseudogap, and highlights distinct physics at the edge of the superconducting dome.
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Distribution coefficients (K(d)) of stable iodine in estuarine and coastal regions, Japan, and their relationship to salinity and organic carbon in sediments.
Environ Monit Assess
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The sediment-water distribution coefficient, (K(d)), is one of the most important parameters in radionuclide assessment models. In this study, we determined K ds of stable iodine (I) in estuarine and coastal regions. We studied 16 estuarine and coastal regions of Japan and obtained I data on water and sediments. Data on salinity, pH, dissolved organic carbon and dissolved oxygen in water, and organic carbon (OC) in sediments were also obtained as estuarine variables. Determined (K(d))S of I in the Sagami River estuary decreased along the salinity gradient (salinity range, 0.1-33.8), indicating that salinity is one of the important factors controlling the (K(d)) values; however, when the (K(d)) values were compared among all the estuaries, the difference between minimum and maximum (K(d)) values varied by about two orders of magnitude in a narrow salinity range of 30.0-34.4. A significant correlation between (K(d)) value and OC content in sediments was observed in all the stations with a salinity of ? 30 except for stations in the Ishikari and Onga River estuaries. The exceptions are probably due to different sources of the sediments, which are explained by the results of relatively low I/OC ratios in sediments in those two estuaries, compared to the other estuaries. Thus, OC in sediments as well as salinity may be responsible for the variation of (K(d))S of I in the estuarine and coastal regions.
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Concise total synthesis of (-)-myxalamide?A.
Angew. Chem. Int. Ed. Engl.
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The MIDA touch: A concise and highly convergent protecting-group-free total synthesis of (-)-myxalamide?A involves a stereoselective vinylogous Mukaiyama aldol reaction of a vinylketene silyl N,O-acetal, together with a one-pot Stille/Suzuki-Miyaura cross-coupling reaction using Burkes N-methyliminodiacetic acid (MIDA) boronate to connect left- and right-hand fragments of the molecule (see scheme).
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Sensitivity control through attenuation of signal transfer efficiency by negative regulation of cellular signalling.
Nat Commun
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Sensitivity is one of the hallmarks of biological and pharmacological responses. However, the principle of controlling sensitivity remains unclear. Here we theoretically analyse a simple biochemical reaction and find that the signal transfer efficiency of the transient peak amplitude attenuates depending on the strength of negative regulation. We experimentally find that many signalling pathways in various cell lines, including the Akt and ERK pathways, can be approximated by simple biochemical reactions and that the same property of the attenuation of signal transfer efficiency was observed for such pathways. Because of this property, a downstream molecule should show higher sensitivity to an activator and lower sensitivity to an inhibitor than an upstream molecule. Indeed, we experimentally verify that S6, which lies downstream of Akt, shows lower sensitivity to an epidermal growth factor receptor inhibitor than Akt. Thus, cells can control downstream sensitivity through the attenuation of signal transfer efficiency by changing the expression level of negative regulators.
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Species differences in the pharmacokinetics of KW-7158 [(2S)-(+)-3,3,3-Trifluoro-2-hydroxy-2-methyl-N-(5,5,10-trioxo-4,10-dihydrothieno[3,2-c][1]benzothiepin-9-yl)propanamide]: formation of hydrolyzed metabolite in human and animals.
Xenobiotica
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Species differences in the pharmacokinetics of KW-7158 [(2S)-(+)-3,3,3-Trifluoro-2-hydroxy-2-methyl-N-(5,5,10-trioxo-4,10-dihydrothieno[3,2-c][1]benzothiepin-9-yl)propanamide] were studied in in vivo and in vitro experiments. The exposure ratio of hydrolyzed metabolite (M2, primary metabolite in human plasma)/KW-7158 was higher than the ratio of thiophen-to-furan converted metabolite (M1)/KW-7158 in human subjects after oral administration, but the mouse, rat and dog studies gave opposite results. M2 was produced in the highest amount by the 9000g supernatant of small intestine, followed by that of liver and kidney in human subjects. After correction for protein contents, the results obtained suggested that the small intestine plays a major role in the metabolism to M2 for the first pass effect after oral administration of KW-7158. The formation of M2 was independent of the presence of NADPH and was inhibited by various esterase inhibitors. These observations suggested that the predominant enzymes or isozymes involved in the formation of M2 are esterases, which differ between humans and animals. Such differences may be one of the reasons for the species differences in the pharmacokinetics of KW-7158 between humans and animals.
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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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