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1.
Sci Rep ; 12(1): 830, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039561

RESUMO

We report a Spectroscopic Imaging Scanning Tunneling Microscopy (SI-STM) study of a DyBa2Cu3O7-δ (DBCO) thin film (Tc ~ 79 K) synthesized by the molecular beam epitaxy (MBE). We observed an unusual transfer of spectral weight in the local density of states (LDOS) spectra occurring only within the superconducting gap. By a systematic control of the tip-sample distance and the junction resistance, we demonstrate that the spectral weight transfer can be switched at a nano-meter length scale. These results suggest that an interaction between the STM tip and the sample alters the electronic configurations in the film. This probably originates from a combination of an intrinsic band bending at the interface between the surface and the bulk, and a tip-induced band bending. These results may open a new avenue for band engineering and applications of thin films of high-Tc cuprates.

2.
Chem Pharm Bull (Tokyo) ; 69(7): 630-638, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33853973

RESUMO

Recently, quantitative NMR (qNMR), especially 1H-qNMR, has been widely used to determine the absolute quantitative value of organic molecules. We previously reported an optimal and reproducible sample preparation method for 1H-qNMR. In the present study, we focused on a 31P-qNMR absolute determination method. An organophosphorus compound, cyclophosphamide hydrate (CP), listed in the Japanese Pharmacopeia 17th edition was selected as the target compound, and the 31P-qNMR and 1H-qNMR results were compared under three conditions with potassium dihydrogen phosphate (KH2PO4) or O-phosphorylethanolamine (PEA) as the reference standard for 31P-qNMR and sodium 4,4-dimethyl-4-silapentanesulfonate-d6 (DSS-d6) as the standard for 1H-qNMR. Condition 1: separate sample containing CP and KH2PO4 for 31P-qNMR or CP and DSS-d6 for 1H-qNMR. Condition 2: mixed sample containing CP, DSS-d6, and KH2PO4. Condition 3: mixed sample containing CP, DSS-d6, and PEA. As conditions 1 and 3 provided good results, validation studies at multiple laboratories were further conducted. The purities of CP determined under condition 1 by 1H-qNMR at 11 laboratories and 31P-qNMR at 10 laboratories were 99.76 ± 0.43 and 99.75 ± 0.53%, respectively, and those determined under condition 3 at five laboratories were 99.66 ± 0.08 and 99.61 ± 0.53%, respectively. These data suggested that the CP purities determined by 31P-qNMR are in good agreement with those determined by the established 1H-qNMR method. Since the 31P-qNMR signals are less complicated than the 1H-qNMR signals, 31P-qNMR would be useful for the absolute quantification of compounds that do not have a simple and separate 1H-qNMR signal, such as a singlet or doublet, although further investigation with other compounds is needed.


Assuntos
Ciclofosfamida/análise , Água/análise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fósforo
3.
Chem Pharm Bull (Tokyo) ; 69(1): 118-123, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33087642

RESUMO

Quantitative NMR (qNMR) is applied to determine the absolute quantitative value of analytical standards for HPLC-based quantification. We have previously reported the optimal and reproducible sample preparation method for qNMR of hygroscopic reagents, such as saikosaponin a, which is used as an analytical standard in the assay of crude drug section of Japanese Pharmacopoeia (JP). In this study, we examined the absolute purity determination of a hygroscopic substance, indocyanine green (ICG), listed in the Japanese Pharmaceutical Codex 2002, using qNMR for standardization by focusing on the adaptation of ICG to JP. The purity of ICG, as an official non-Pharmacopoeial reference standard (non-PRS), had high variation (86.12 ± 2.70%) when preparing qNMR samples under non-controlled humidity (a conventional method). Additionally, residual ethanol (0.26 ± 0.11%) was observed in the non-PRS ICG. Next, the purity of non-PRS ICG was determined via qNMR when preparing samples under controlled humidity using a saturated sodium bromide solution. The purity was 84.19 ± 0.47% with a lower variation than that under non-controlled humidity. Moreover, ethanol signal almost disappeared. We estimated that residual ethanol in non-PRS ICG was replaced with water under controlled humidity. Subsequently, qNMR analysis was performed when preparing samples under controlled humidity in a constant temperature and humidity box. It showed excellent results with the lowest variation (82.26 ± 0.19%). As the use of a constant temperature and humidity box resulted in the lowest variability, it is recommended to use the control box if the reference ICG standard is needed for JP assays.


Assuntos
Verde de Indocianina/análise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Molhabilidade
4.
J Nat Med ; 75(1): 232-239, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33200287

RESUMO

Obesity is a risk factor for many diseases, including type 2 diabetes and cardiovascular disease, and is related to the rising morbidity and mortality. Discovery of agents targeting adipogenesis, especially from natural sources, is important for the treatment of obesity. Here, we aimed to identify anti-adipogenic substances in methanol extracts of Physalis peruviana and to investigate their effect, along with underlying mechanisms. Activity-guided fractionation of the extract revealed 4ß-hydroxywithanolide E (HWE) and withanolide E (WE) as the adipogenesis inhibitors. Both compounds suppressed mRNA expression of central adipogenic transcription factors, peroxisome proliferator-activated receptor γ, and CCAAT/enhancer-binding protein α in the early stage of adipocyte differentiation. The inhibitory action of these two withanolides on adipogenesis was largely limited to this stage. The proliferation of preadipocytes was markedly suppressed by treatment with HWE and WE for 24 and 48 h in the differentiation medium, and cell-cycle arrest in the G0/G1 phase was observed. Therefore, our results suggested that withanolides from P. peruviana to be novel anti-adipogenic compounds that modulate mitotic clonal expansion.


Assuntos
Células 3T3-L1/metabolismo , Hematopoiese Clonal/efeitos dos fármacos , Physalis/química , Extratos Vegetais/química , Ribes/química , Vitanolídeos/metabolismo , Adipócitos/metabolismo , Animais , Diferenciação Celular , Humanos , Camundongos , Mitose
5.
Chem Pharm Bull (Tokyo) ; 68(9): 868-878, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32565492

RESUMO

NMR spectroscopy has recently been utilized to determine the absolute amounts of organic molecules with metrological traceability since signal intensity is directly proportional to the number of each nucleus in a molecule. The NMR methodology that uses hydrogen nucleus (1H) to quantify chemicals is called quantitative 1H-NMR (1H qNMR). The quantitative method using 1H qNMR for determining the purity or content of chemicals has been adopted into some compendial guidelines and official standards. However, there are still few reports in the literature regarding validation of 1H qNMR methodology. Here, we coordinated an international collaborative study to validate a 1H qNMR based on the use of an internal calibration methodology. Thirteen laboratories participated in this study, and the purities of three samples were individually measured using 1H qNMR method. The three samples were all certified via conventional primary methods of measurement, such as butyl p-hydroxybenzoate Japanese Pharmacopeia (JP) reference standard certified by mass balance; benzoic acid certified reference material (CRM) certified by coulometric titration; fludioxonil CRM certified by a combination of freezing point depression method and 1H qNMR. For each sample, 1H qNMR experiments were optimized before quantitative analysis. The results showed that the measured values of each sample were equivalent to the corresponding reference labeled value. Furthermore, assessment of these 1H qNMR data using the normalized error, En-value, concluded that statistically 1H qNMR has the competence to obtain the same quantification performance and accuracy as the conventional primary methods of measurement.


Assuntos
Espectroscopia de Ressonância Magnética/normas , Ácido Benzoico/química , Calibragem , Dioxóis/química , Hidroxibenzoatos/química , Cooperação Internacional , Espectroscopia de Ressonância Magnética/métodos , Pirróis/química , Padrões de Referência , Reprodutibilidade dos Testes
6.
J Food Biochem ; 44(7): e13268, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32412116

RESUMO

As a Japanese folk medicine, Tithonia diversifolia is used for cardiovascular disease prevention and health maintenance. We isolated T. diversifolia-derived orizabin based on the nitric oxide production inhibitory effect. This study aimed to consider orizabin as a novel functional compound with anti-atherosclerotic activity. Orizabin significantly inhibited the adhesion of THP-1 cells to human umbilical vein endothelial cells (HUVECs) and suppressed the mRNA expression of adhesion molecules in HUVECs. In Phorbol 12-myristate 13-acetate stimulated THP-1 cells, orizabin suppressed macrophage differentiation, CD36 expression (1% at 10 µM), and NFκB transcriptional activity. Furthermore, orizabin suppressed oxidized low-density lipoprotein (oxLDL) uptake in macrophages and the Akt phosphorylation. On the contrary, we revealed that phosphatidylinositol-3,4,5-trisphosphate 3-phosphatase (PTEN) mRNA and protein expression were promoted significantly by orizabin (mRNA, 270-fold at 10 µM). Our study presented the possibility that T. diversifolia-derived orizabin is novel anti-atherosclerotic compound via the suppression of Akt phosphorylation, and T. diversifolia may be effective as a new crop for vascular health maintenance. PRACTICAL APPLICATIONS: In this study, the differentiation of monocytes was suppressed without any toxicity, it was obvious in the image, and the oxLDL uptake in monocytes was clearly suppressed by orizabin. Our findings presented that T. diversifolia-derived compound orizabin specifically contributes to the promotion of PTEN expression and suppression of Akt signal in cells, and acts to suppress inflammation by suppression of NFκB transcriptional activity. As a component derived from food, it has a strong function and can be used to maintain the health for blood vessels. It is also a finding that deserves to expand production currently being carried out on a small scale. Furthermore, the promoting effect of PTEN known as a cancer suppressor in orizabin may result in further use for pharmaceuticals research. Orizabin can be safely used as a food-derived compound for maintaining human health.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Tithonia , Adesão Celular , Diferenciação Celular , Humanos , Lipoproteínas LDL , PTEN Fosfo-Hidrolase/genética , Monoéster Fosfórico Hidrolases , Células THP-1
7.
Biol Pharm Bull ; 43(5): 898-903, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378565

RESUMO

Bone loss and bone-related disease are associated with the deregulation of osteoclast function, and therefore agents that affect osteoclastogenesis have attracted attention. The purpose of the present study was to discover modified kavalactone analogs as potential anti-osteoclastogenic agents. We assessed the effect of 26 analogs on osteoclast differentiation in vitro. The most potent compound, (E)-6-(2-fluorostyryl)-4-methoxy-2H-pyran-2-one (22), suppressed receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenic differentiation of RAW264 cells with IC50 values of 4.3 µM. A partial structure-activity relationship study revealed the importance of fluorine and its position within the 5,6-dehydrokawain skeleton. The results of a pit formation assay suggested that compound 22 prevents osteoclastic bone resorption by inhibiting osteoclastogenesis. Moreover, compound 22 downregulated mRNA expression levels of RANKL-induced nuclear factor of activated T cells c1 (NFATc1) and osteoclastogenesis-related genes. These results suggest that (E)-6-(2-fluorostyryl)-4-methoxy-2H-pyran-2-one scaffold could lead to the identification of new anti-resorptive agents.


Assuntos
Lactonas/farmacologia , Osteoclastos/efeitos dos fármacos , Pironas/farmacologia , Estirenos/farmacologia , Animais , Reabsorção Óssea , Diferenciação Celular/efeitos dos fármacos , Flúor , Camundongos , Osteogênese/efeitos dos fármacos , Ligante RANK , Células RAW 264.7
8.
Nature ; 580(7801): 65-70, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238945

RESUMO

The defining characteristic1,2 of Cooper pairs with finite centre-of-mass momentum is a spatially modulating superconducting energy gap Δ(r), where r is a position. Recently, this concept has been generalized to the pair-density-wave (PDW) state predicted to exist in copper oxides (cuprates)3,4. Although the signature of a cuprate PDW has been detected in Cooper-pair tunnelling5, the distinctive signature in single-electron tunnelling of a periodic Δ(r) modulation has not been observed. Here, using a spectroscopic technique based on scanning tunnelling microscopy, we find strong Δ(r) modulations in the canonical cuprate Bi2Sr2CaCu2O8+δ that have eight-unit-cell periodicity or wavevectors Q ≈ (2π/a0)(1/8, 0) and Q ≈ (2π/a0)(0, 1/8) (where a0 is the distance between neighbouring Cu atoms). Simultaneous imaging of the local density of states N(r, E) (where E is the energy) reveals electronic modulations with wavevectors Q and 2Q, as anticipated when the PDW coexists with superconductivity. Finally, by visualizing the topological defects in these N(r, E) density waves at 2Q, we find them to be concentrated in areas where the PDW spatial phase changes by π, as predicted by the theory of half-vortices in a PDW state6,7. Overall, this is a compelling demonstration, from multiple single-electron signatures, of a PDW state coexisting with superconductivity in Bi2Sr2CaCu2O8+δ.

9.
Proc Natl Acad Sci U S A ; 116(27): 13249-13254, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31160468

RESUMO

The CuO2 antiferromagnetic insulator is transformed by hole-doping into an exotic quantum fluid usually referred to as the pseudogap (PG) phase. Its defining characteristic is a strong suppression of the electronic density-of-states D(E) for energies |E| < [Formula: see text], where [Formula: see text] is the PG energy. Unanticipated broken-symmetry phases have been detected by a wide variety of techniques in the PG regime, most significantly a finite-Q density-wave (DW) state and a Q = 0 nematic (NE) state. Sublattice-phase-resolved imaging of electronic structure allows the doping and energy dependence of these distinct broken-symmetry states to be visualized simultaneously. Using this approach, we show that even though their reported ordering temperatures T DW and T NE are unrelated to each other, both the DW and NE states always exhibit their maximum spectral intensity at the same energy, and using independent measurements that this is the PG energy [Formula: see text] Moreover, no new energy-gap opening coincides with the appearance of the DW state (which should theoretically open an energy gap on the Fermi surface), while the observed PG opening coincides with the appearance of the NE state (which should theoretically be incapable of opening a Fermi-surface gap). We demonstrate how this perplexing phenomenology of thermal transitions and energy-gap opening at the breaking of two highly distinct symmetries may be understood as the natural consequence of a vestigial nematic state within the pseudogap phase of Bi2Sr2CaCu2O8.

10.
Shokuhin Eiseigaku Zasshi ; 59(5): 223-227, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30429421

RESUMO

The official method described in Direction Notification Kanshoku No. 99 (May 8, 1981) for the determination of chlorophyll decomposition products including pheophorbide was verified and improved in order to overcome several problems. Firstly, extraction with a mortar required improvement because of the difficulty of maintaining equal power for a long time. Secondly, the saturated sodium sulfate reagent caused a red-shift of the absorption maximum wavelength from the measured wavelength given in the official method; consequently, the absorption was decreased and a new absorption peak was detected around 729 nm. As a result, chlorophyll decomposition products including pheophorbide were underestimated. Lastly, it was impossible to make up the volume of the diethyl ether layer accurately to 20 mL before measuring the absorption. These points were improved in the modified method, and a validation test was performed. The mean recovery was 82.7% and the within-laboratory reproducibility was 5.8%.


Assuntos
Clorofila/análogos & derivados , Clorofila/análise , Reprodutibilidade dos Testes
11.
Shokuhin Eiseigaku Zasshi ; 59(5): 248-256, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30429425

RESUMO

New analytical methods for the determination of free asparagine (Asn), which is a precursor of acrylamide, in grains were developed using LC-MS and LC-MS/MS. Asn was extracted from a sample with 5% (w/v) aqueous trichloroacetic acid solution, appropriately diluted with 0.1% (v/v) formic acid solution, and then analyzed by LC-MS or LC-MS/MS. HPLC separation was performed by isocratic elution on a Penta Fluoro Phenyl (PFP) column using 0.1% (v/v) formic acid and acetonitrile mixture as the mobile phase. The calibration curve was linear in the range of 0.005-0.1 µg/mL. The mean recoveries from potato starch, non-glutinous rice flour and whole wheat flour ranged from 95.4 to 100.9%, repeatability (RSD) ranged from 0.9 to 6.0%, and within-laboratory reproducibility (RSDwr) ranged from 2.8 to 7.1%. Limits of quantitation (LOQs) were 7 mg/kg for potato starch, and 5 mg/kg for non-glutinous rice flour. In addition, an inter-laboratory study was performed in 10 laboratories using 5 kinds of grains (non-glutinous brown rice flour, corn flour, strong flour, whole wheat flour, and whole rye flour), which naturally contained free asparagine. The HORRATR values ranged from 0.4 to 1.0. These results are within the range of the procedural manual of the Codex Alimentarius Commission, confirming the effectiveness of the developed procedures.


Assuntos
Asparagina/análise , Grão Comestível/química , Análise de Alimentos/métodos , Cromatografia Líquida , Farinha/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
12.
J Oleo Sci ; 67(10): 1279-1289, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30210077

RESUMO

Herein, to achieve individual and concomitant quantifications of phospholipid classes, an absolute quantification 31P NMR method using an internal standard was examined. Phospholipid standards and dietary foods were dispersed to prepare test solutions in an anionic surfactant (sodium cholate) solution containing EDTA, as a modification based on a reported method. Each phospholipid class showed a reproducible chemical shift at a near-neutral test solution pH of 6.90±0.04 and temperature of 30.0±0.1°C. The quantity of synthetic phosphatidylcholine measured using 31P NMR was consistent with that measured by 1H NMR using an internal standard. As the principal phospholipid class of soybean and egg yolk lecithin is phosphatidylcholine, the measurement conditions of 31P NMR (pulse interval time and number of scans) were optimized such that minor phospholipids, including lysophospholipids, also present in lecithin could be quantified simultaneously. Phospholipid classes in commercial polar lipid samples derived from porcine brain, yeast, and soybean were individually quantified using the above conditions. Using phosphoserine as the internal standard material allowed the absolute molar quantity of the phospholipid class to be precisely determined with traceability to the SI. The determined molar amounts of phospholipid classes were then translated to the weight amount by assuming that each phospholipid class contained two stearic acid molecules as the constituent fatty acid. The calculated total contents of each phospholipid class by 31P NMR were in good agreement with those obtained by molybdenum blue colorimetry. Furthermore, the quantitative values of the principal phospholipid classes in the polar lipid samples obtained by 31P NMR corresponded in a broad view, however, was more informative for the separation of individual phospholipid species rather than the quantitative 2D thin-layer chromatography.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Fosfolipídeos/análise , Fosfolipídeos/isolamento & purificação , Hidrogênio , Fosfolipídeos/classificação , Fosfolipídeos/normas , Fósforo
13.
Shokuhin Eiseigaku Zasshi ; 59(4): 187-191, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30158398

RESUMO

In order to validate an HPLC-UV method for the determination of free asparagine, which is a precursor of acrylamide, in grains using dansyl derivatization, an inter-laboratory study was performed in 9 laboratories using 5 kinds of grains (non-glutinous brown rice flour, corn flour, strong flour, whole wheat flour, and whole rye flour), which naturally contain free asparagine. The relative standard deviations for repeatability (RSDr) and reproducibility (RSDr) were in the ranges of 0.5-2.2 and 2.3-5.9%, respectively. The HorRat values ranged from 0.4 to 0.6. These results were within the range of the procedural manual of the Codex Alimentarius Commission, and therefore the method is effective.


Assuntos
Asparagina/análise , Grão Comestível/química , Farinha/análise , Acrilamida , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes
14.
Biopharm Drug Dispos ; 39(3): 164-174, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29451686

RESUMO

We previously reported that KW-2449, (E)-1-{4-[2-(1H-Indazol-3-yl)vinyl]benzoyl}piperazine, a novel multikinase inhibitor developed for the treatment of leukemia patients, was oxidized to an iminium ion intermediate by monoamine oxidase B (MAO-B) and then converted to its oxo-piperazine form (M1) by aldehyde oxidase (AO). However, it was found that the significant decrease in the pharmacologically active metabolite M1 following repeated administration of KW-2449 in primates might hamper the effectiveness of the drug. The mechanism underlying this phenomenon was investigated and it was found that the AO activity was inhibited in a time-dependent manner in vitro under the co-incubation of KW-2449 and MAO-B, while neither KW-2449 nor M1 strongly inhibited MAO-B or AO activity. These results clearly suggest that MAO-B catalysed iminium ion metabolite inhibited AO, prompting us to investigate whether or not the iminium ion metabolite covalently binds to endogenous proteins, as has been reported with other reactive metabolites as a cause for idiosyncratic toxicity. The association of the radioactivity derived from 14 C-KW-2449 with endogenous proteins both in vivo and in vitro was confirmed and it was verified that this covalent binding was inhibited by the addition of sodium cyanide, an iminium ion-trapping reagent, and pargyline, a MAO-B inhibitor. These findings strongly suggest that the iminium ion metabolite of KW-2449 is highly reactive in inhibiting AO irreversibly and binding to endogenous macromolecules covalently.


Assuntos
Aldeído Oxidase/antagonistas & inibidores , Indazóis/metabolismo , Indazóis/farmacologia , Piperazinas/metabolismo , Piperazinas/farmacologia , Proteínas/metabolismo , Aldeído Oxidase/metabolismo , Animais , Isótopos de Carbono , Humanos , Macaca fascicularis , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Oxirredução , Pargilina/farmacologia , Ligação Proteica , Ensaio Radioligante , Cianeto de Sódio/farmacologia
15.
Eur J Nutr ; 56(3): 949-964, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26704713

RESUMO

PURPOSE: The rhizome of Kaempferia parviflora (KP) is used in traditional Thai medicine. In this study, we investigated the effects of an ethanol KP extract and two of its components [5,7-dimethoxyflavone (DMF) and 5-hydroxy-3,7,3',4'-tetramethoxyflavone (TMF)] on monocyte adhesion and cellular reactive oxygen species (ROS) production in human umbilical vein endothelial cells (HUVECs), which provide an in vitro model of events relevant to the development and progression of atherosclerosis. METHODS: RAW264.7 mouse macrophage-like cells were incubated with various concentrations of KP extract or polymethoxyflavonoids and stimulated with lipopolysaccharide prior to measuring nitrite levels in the culture media. Monocyte adhesion was evaluated by measuring the fluorescently labeled human monocytic leukemia THP-1 cells that is attached to tumor necrosis factor-α (TNF-α)-stimulated HUVECs. Cellular ROS production was assessed by measuring cellular antioxidant activity using pyocyanin-stimulated HUVECs. RESULTS: KP extract and DMF reduced nitrite levels (as indicator of nitric oxide production) in LPS-stimulated RAW264.7 cells and also inhibited THP-1 cell adhesion to HUVECs. These treatments induced mRNA expression of endothelial nitric oxide synthase in TNF-α-stimulated HUVECs and downregulated that of various cell adhesion molecules, inflammatory mediators, and endothelial function-related genes. Angiotensin-converting enzyme activity was inhibited by KP extract in vitro. Furthermore, KP extract, DMF, and TMF inhibited the production of cellular ROS in pyocyanin-stimulated HUVECs. CONCLUSION: KP extract, DMF, and TMF showed potential anti-inflammatory and antioxidant effects in these in vitro models, properties that would inhibit the development and progression of atherosclerosis.


Assuntos
Adesão Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Zingiberaceae/química , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Regulação para Baixo , Flavonoides/farmacologia , Humanos , Lipopolissacarídeos/metabolismo , Camundongos , Monócitos/citologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
16.
Shokuhin Eiseigaku Zasshi ; 58(6): 247-252, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-29311443

RESUMO

A novel analytical method was developed for the determination of free asparagine (Asn), which is a precursor of acrylamide, in grains. Asn was extracted from a sample with 5% (w/v) aqueous trichloroacetic acid solution, and the crude extract was cleaned up using a reversed-phase solid-phase cartridge. The cleaned extract was derivatized with dansyl chloride and analyzed by HPLC-UV. HPLC separation was performed by gradient elution on a ODS column using 0.01 mol/L ammonium acetate and acetonitrile mixture as the mobile phase. The calibration curve was linear in the range of 0.5-100 µg/mL. The mean recoveries from potato starch, non-glutinous rice flour and whole wheat flour ranged from 97.7 to 102.6%, the repeatability (RSDs) ranged from 0.8 to 2.0%, and the within-laboratory reproducibility (RSDwr) ranged from 1.4 to 6.2%. Limits of quantitation (LOQs) were 13 mg/kg for potato starch and 4 mg/kg for non-glutinous rice flour. The quantitative values obtained for about 15 kinds of grains using this developed method were approximately equal to those obtained with an automatic amino acid analyzer.


Assuntos
Asparagina/análise , Cromatografia Líquida de Alta Pressão/métodos , Grão Comestível/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Acrilamida , Farinha/análise , Reprodutibilidade dos Testes , Raios Ultravioleta
17.
Shokuhin Eiseigaku Zasshi ; 57(5): 160-165, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-27784867

RESUMO

Discriminating vegetable oils and animal and milk fats by infrared absorption spectroscopy is difficult due to similarities in their spectral patterns. Therefore, a rapid and simple method for analyzing vegetable oils, animal fats, and milk fats using TOF/MS with an APCI direct probe ion source was developed. This method enabled discrimination of these oils and fats based on mass spectra and detailed analyses of the ions derived from sterols, even in samples consisting of only a few milligrams. Analyses of the mass spectra of processed foods containing oils and milk fats, such as butter, cheese, and chocolate, enabled confirmation of the raw material origin based on specific ions derived from the oils and fats used to produce the final product.


Assuntos
Gorduras/análise , Análise de Alimentos/métodos , Manipulação de Alimentos , Espectrometria de Massas/métodos , Óleos Vegetais/análise , Espectrometria de Massas/instrumentação
18.
Proc Natl Acad Sci U S A ; 113(45): 12661-12666, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27791157

RESUMO

Theories based upon strong real space (r-space) electron-electron interactions have long predicted that unidirectional charge density modulations (CDMs) with four-unit-cell (4a0) periodicity should occur in the hole-doped cuprate Mott insulator (MI). Experimentally, however, increasing the hole density p is reported to cause the conventionally defined wavevector QA of the CDM to evolve continuously as if driven primarily by momentum-space (k-space) effects. Here we introduce phase-resolved electronic structure visualization for determination of the cuprate CDM wavevector. Remarkably, this technique reveals a virtually doping-independent locking of the local CDM wavevector at [Formula: see text] throughout the underdoped phase diagram of the canonical cuprate Bi2Sr2CaCu2O8 These observations have significant fundamental consequences because they are orthogonal to a k-space (Fermi-surface)-based picture of the cuprate CDMs but are consistent with strong-coupling r-space-based theories. Our findings imply that it is the latter that provides the intrinsic organizational principle for the cuprate CDM state.

19.
Anal Sci ; 32(7): 729-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27396652

RESUMO

Okadaic acid (OA), a lipophilic shellfish toxin, was accurately quantified using quantitative nuclear magnetic resonance with internal standards for the development of an authentic reference standard. Pyridine and the residual proton in methanol-d4 were used as removable internal standards to limit any contamination. They were calibrated based on a maleic acid certified reference material. Thus, the concentration of OA was traceable to the SI units through accurate quantitative NMR with an internal reference substance. Signals from the protons on the oxygenated and unsaturated carbons of OA were used for quantification. A reasonable accuracy was obtained by integrating between the lower and upper (13)C satellite signal range when more than 4 mg of OA was used. The best-determined purity was 97.4% (0.16% RSD) when 20 mg of OA was used. Dinophysistoxin-1, a methylated analog of OA having an almost identical spectrum, was also quantified by using the same methodology.


Assuntos
Dinoflagelados/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Toxinas Marinhas/análise , Ácido Okadáico/análise , Piranos/análise , Frutos do Mar/análise , Calibragem , Padrões de Referência , Sensibilidade e Especificidade
20.
Biosci Biotechnol Biochem ; 80(7): 1425-32, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26940726

RESUMO

Bone homeostasis is maintained by balancing bone formation and bone resorption, but an imbalance between them is associated with various bone-related diseases such as osteoporosis and rheumatoid arthritis. We found that 5,6-dehydrokawain (DK) and dihydro-5,6-dehydrokawain (DDK), which were isolated as promising compounds from Alpinia zerumbet rhizomes, promote differentiation of osteoblastic MC3T3-E1 cells. DK and DDK increased the alkaline phosphatase activity and matrix mineralization of MC3T3-E1 cells. DK exerts larger effects than DDK. The gene expression of runt-related transcription factor 2 and osterix, which are essential transcription factors in the early period of osteoblast differentiation, was significantly increased by DK treatment. The mRNA level of distal-less homeobox 5 was also enhanced by DK treatment, and DK activated the p38 mitogen-activated protein kinase pathway. Therefore, DK may have clinical potential for preventing osteoporosis, and could be considered as a potential anabolic therapeutic agent.


Assuntos
Alpinia/química , Diferenciação Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Pironas/farmacologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/agonistas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/genética , Extratos Vegetais/química , Pironas/isolamento & purificação , RNA Mensageiro/agonistas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rizoma/química , Fator de Transcrição Sp7 , Fatores de Transcrição/agonistas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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