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1.
J Phys Condens Matter ; 36(32)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38670081

RESUMO

This study performs extended x-ray absorption fine structure (EXAFS) measurements for the S-K edge in the temperature range of 10 and 300 K in the transmission mode using a photodiode to detect the transmitted x-rays. It provides the first report of temperature variations in the structural parameters ofα-S. As the temperature increases from 10 to 300 K in the Fourier transform ofkχ(k)the first peak corresponding to the covalent bond of the eight-membered ring becomes slightly low anomalously despite thermal disturbances. However, as in normal materials, the second peak at 300 K decreases to approximately half of that at 10 K, which contains several intra- and inter-ring correlations. All structural parameters of the covalent bond obtained by nonlinear least squares fitting exhibit missing temperature variations. A value of zero for the asymmetric parameter in the EXAFS (C3) implies that the potential of the covalent bond is symmetric, and the constant value of the mean square relative displacement (MSRD) with temperature implies that the potential is extremely high. The Einstein model fitting for the temperature variation in the MSRD yields an Einstein temperature of 942 K and force constant (K) of 405 N m-1. The value ofKis the largest among those of chalcogen elements.

2.
Phys Rev Lett ; 131(15): 159904, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897793

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.99.165503.

3.
Biosci Biotechnol Biochem ; 85(5): 1252-1265, 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33728459

RESUMO

ω3 Polyunsaturated fatty acids are currently obtained mainly from fisheries; thus, sustainable alternative sources such as oleaginous microorganisms are required. Here, we describe the isolation, characterization, and application of 3 novel ω3 desaturases with ω3 polyunsaturated fatty acid-producing activity at ordinary temperatures (28 °C). First, we selected Pythium sulcatum and Plectospira myriandra after screening for oomycetes with high eicosapentaenoic acid/arachidonic acid ratios and isolated the genes psulω3 and pmd17, respectively, which encode ω3 desaturases. Subsequent characterization showed that PSULω3 exhibited ω3 desaturase activity on both C18 and C20 ω6 polyunsaturated fatty acids while PMD17 exhibited ω3 desaturase activity exclusively on C20 ω6 polyunsaturated fatty acids. Expression of psulω3 and pmd17 in the arachidonic acid-producer Mortierella alpina resulted in transformants that produced eicosapentaenoic acid/total fatty acid values of 38% and 40%, respectively, at ordinary temperatures. These ω3 desaturases should facilitate the construction of sustainable ω3 polyunsaturated fatty acid sources.


Assuntos
Ácido Eicosapentaenoico/biossíntese , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Insaturados/biossíntese , Mortierella/genética , Oomicetos/genética , Pythium/genética , Ácido Araquidônico/biossíntese , Clonagem Molecular , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/classificação , Expressão Gênica , Biblioteca Gênica , Engenharia Metabólica/métodos , Mortierella/enzimologia , Oomicetos/classificação , Oomicetos/enzimologia , Filogenia , Plasmídeos/química , Plasmídeos/metabolismo , Pythium/classificação , Pythium/enzimologia , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Transformação Genética , Transgenes
4.
FEBS Open Bio ; 11(4): 1144-1152, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33605550

RESUMO

Ghrelin is an endogenous orexigenic hormone mainly produced by stomach cells and is reported to influence appetite, gastrointestinal motility and growth hormone secretion. We observed that enzymatic digest of wheat gluten stimulated ghrelin secretion from mouse ghrelinoma 3-1, a ghrelin-releasing cell line. Further on, we characterized the ghrelin-releasing peptides present in the digest by comprehensive peptide analysis using liquid chromatography-mass spectrometry and structure-activity relationship. Among the candidate peptides, we found that SQQQQPVLPQQPSF, LSVTSPQQVSY and YPTSL stimulated ghrelin release. We then named them wheat-ghretropin A, B and C, respectively. In addition, we observed that wheat-ghretropin A increased plasma ghrelin concentration and food intake in mice after oral administration. Thus, we demonstrated that wheat-ghretropin stimulates ghrelin release both in vitro and in vivo. To the best of our knowledge, this is the first report of a wheat-derived exogenous bioactive peptide that stimulates ghrelin secretion.


Assuntos
Grelina/química , Grelina/metabolismo , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/metabolismo , Triticum/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Cromatografia Líquida , Quimotripsina/química , Glutens/química , Hidrólise , Espectrometria de Massas , Camundongos , Camundongos Transgênicos , Proteólise , Relação Estrutura-Atividade
5.
Molecules ; 25(20)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066465

RESUMO

Testosterone plays an important role in male sexual characteristics and maturation, and decreased testosterone levels increase the risk of several diseases. Recently, onion extract rich in cysteine sulfoxides, which are amino acids unique to onions, has been reported to alleviate age-related symptoms resulting from decreased testosterone levels in males. However, the mechanism underlying the suppression of low testosterone levels by cysteine sulfoxides has not been elucidated. In this study, we found that onion extract containing cysteine sulfoxides enhanced progesterone, a precursor of testosterone, in mouse testis-derived I-10 tumor cells. Furthermore, cysteine sulfoxides activated protein kinase A (PKA) and cyclic adenosine monophosphate response element-binding protein, which are key factors in steroidogenesis. These results suggest that cysteine sulfoxides enhance steroid hormone production via activation of the PKA signaling pathway.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Cisteína/análogos & derivados , Progesterona/metabolismo , Neoplasias Testiculares/patologia , Animais , Linhagem Celular Tumoral , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Cisteína/química , Cisteína/farmacologia , Masculino , Camundongos , Cebolas/química , Ácidos Pipecólicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Transdução de Sinais , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/metabolismo
6.
J Synchrotron Radiat ; 27(Pt 4): 1069-1073, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33566017

RESUMO

Grazing-incidence small-angle X-ray scattering (GISAXS) patterns have multiple superimposed contributions from the shape of the nanoscale structure, the coupling between the particles, the partial pair correlation, and the layer geometry. Therefore, it is not easy to identify the model manually from the huge amounts of combinations. The convolutional neural network (CNN), which is one of the artificial neural networks, can find regularities to classify patterns from large amounts of combinations. CNN was applied to classify GISAXS patterns, focusing on the shape of the nanoparticles. The network found regularities from the GISAXS patterns and showed a success rate of about 90% for the classification. This method can efficiently classify a large amount of experimental GISAXS patterns according to a set of model shapes and their combinations.


Assuntos
Nanopartículas/ultraestrutura , Redes Neurais de Computação , Difração de Raios X , Espalhamento a Baixo Ângulo
7.
Sci Rep ; 4: 4732, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24751752

RESUMO

We conducted a preliminary investigation of the effects of visible light irradiation on plant extracts, and we observed a strong suppressive effect on interleukin (IL) 2 expression with the inhibition of c-Jun amino-terminal kinase (JNK) phosphorylation in Jurkat cells by visible light irradiation to ethanol extract from green soybeans (LIEGS). This effect was produced only by extracts from green soybeans (Glycine max) and not other-color soybeans. LIEGS suppressed the lipopolysaccharide-induced IL-6, IL-12 and TNF-α expression levels in human monocyte THP-1 cells in a concentration-dependent manner. LIEGS was applied for 8 weeks to NC/Nga mice. LIEGS suppressed the development of atopic dermatitis (AD)-like skin lesions and reduced the dermatitis scores of the mice. The light irradiation changed the various types of small-molecule compounds in extracts. Visible light irradiation to daidzein with chlorophyll b induced a novel oxidative product of daidzein. This product suppressed IL-2 expression in Jurkat cells.


Assuntos
Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/efeitos da radiação , Glycine max/química , Luz , Extratos Vegetais/farmacologia , Extratos Vegetais/efeitos da radiação , Animais , Anti-Inflamatórios/química , Citocinas/metabolismo , Dermatite Atópica/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-2/biossíntese , Células Jurkat , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Extratos Vegetais/química
8.
J Synchrotron Radiat ; 21(Pt 2): 409-12, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24562563

RESUMO

The local structure of an amorphous tellurium (a-Te) film was investigated by extended X-ray absorption fine-structure analysis. The covalent bond length shortens and the Debye-Waller factor of the intra-chain decreases in a-Te compared with trigonal Te (t-Te). The value of the intra-chain coordination number is close to two, which is the value for t-Te, and the inter-chain interaction weakens. These results suggest that the primary chain structure remains intact, but the secondary structure is disrupted. The decrease in the inter-chain interaction strengthens the intra-chain interaction.

9.
Food Chem ; 138(4): 2300-5, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23497889

RESUMO

The present study was performed to investigate the immune-modulating activities of extracts from green soybean (Glycine max) in a 2,4-toluene diisocyanate (TDI)-inducing guinea pig rhinitis model and a human trial study for allergic rhinitis. Hot water extracts of green soybean were chosen for animal experimentation on the basis of their ability to regulate the production of B cell-activating factor of the TNF family and a proliferation-inducing ligand in mouse spleen cells. Green soybean extracts significantly decreased the levels of ovalubumin (OVA)-specific IgE in mice and significantly suppressed the TDI-induced nasal mucosa secretion. An open-label human pilot study was performed on 16 subjects, using Japanese cedar pollinosis. The symptom scores for Japanese cedar pollinosis were better in the long-term green soybean extracts intake group than in the withdrawal short-term intake group. Green soybean extracts had great potential as an orally active immune modulator for the treatment of various allergic diseases.


Assuntos
Glycine max/química , Fatores Imunológicos/administração & dosagem , Extratos Vegetais/administração & dosagem , Rinite Alérgica Sazonal/tratamento farmacológico , Rinite Alérgica Sazonal/imunologia , Adulto , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Feminino , Cobaias , Humanos , Imunoglobulina E/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Projetos Piloto , Pólen/imunologia , Rinite Alérgica Sazonal/genética , Sementes/química , Sementes/crescimento & desenvolvimento , Glycine max/crescimento & desenvolvimento
10.
Clin Nucl Med ; 36(8): 643-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21716013

RESUMO

PURPOSE: Kawasaki disease (KD) is an acute febrile disorder of unknown etiology. Brain single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) help in detecting regional cerebral blood flow abnormalities and brain damage. The usefulness of SPECT and MRI in patients with KD was evaluated. MATERIALS AND METHODS: All 22 patients with KD underwent brain SPECT using Tc-99m-hexamethyl propylene amine oxime from 6 days to 3 years after onset, and 8 patients underwent brain MRI. Of the 22 patients, 4 had neurologic symptoms. Case 1 showed prolonged apnea; case 2, prolonged disturbance of consciousness; and cases 3 and 4 generalized tonic-clonic seizures. Initial brain SPECT showed localized hypoperfusion in 4 and 13 patients with and without neurologic symptoms, respectively. RESULTS: All patients with neurologic symptoms underwent follow-up SPECT; localized hypoperfusion was detected between 1- and 6-month follow-up in 3 of these patients. Six patients without neurologic symptoms underwent follow-up SPECT. Localized hypoperfusion was detected at approximately 1- to 11-month follow-up in 4 of these patients. Diffusion-weighted imaging revealed abnormal high-intensity areas in the corpus callosum in case 1. Case 2 showed a bilateral chronic subdural hematoma with decreased size and ischemic changes, and case 3 showed bilateral hippocampal atrophy and left hippocampal sclerosis. CONCLUSIONS: Because the occurrence of localized hypoperfusion is possibly not restricted to only the acute phase in KD, brain SPECT and MRI should also be performed in KD patients with neurologic symptoms.


Assuntos
Circulação Cerebrovascular , Síndrome de Linfonodos Mucocutâneos/fisiopatologia , Fluxo Sanguíneo Regional , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Síndrome de Linfonodos Mucocutâneos/diagnóstico por imagem , Síndrome de Linfonodos Mucocutâneos/patologia , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único
11.
Phys Rev Lett ; 99(16): 165503, 2007 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-17995265

RESUMO

Extended x-ray absorption fine structure measurements were performed on trigonal tellurium (t-Te) and tellurium nanoparticles in very thin films. Twofold coordinated chains, much like those in t-Te, exist even in the nanoparticles, but covalent bonds or intrachain interactions are stronger than those of t-Te as shown by a shorter bond length and higher Einstein temperature. The interchain coordination number of the nanoparticles is about half that of t-Te, suggesting reduction of interchain interactions.

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