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1.
Chem Pharm Bull (Tokyo) ; 69(6): 526-528, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34078798

RESUMO

The optical property of fluorescent unit-conjugated aliphatic oxaboroles has been investigated. The oxaboroles provide good fluorescence quantum yields and selective recognition toward D-ribose and D-ribose containing molecules. The molecular recognition induced significant fluorescence quenching. The property of the boroles showed the possibility of the boron-based nicotinamide adenine dinucleotide (NAD) sensor probe.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , NAD/química , Açúcares/análise , Compostos de Boro/síntese química , Corantes Fluorescentes/síntese química , Estrutura Molecular , Fenômenos Ópticos
2.
J Nat Prod ; 82(9): 2368-2378, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31442048

RESUMO

A CH3OH-CH2Cl2 (1:1) extract (N025439) of the leaves and twigs of Cryptocarya laevigata furnished eight new compounds, 1-8. Based on extensive 1D and 2D NMR spectroscopic data examination, the new δ-lactone derivatives 1-6 are monoterpene-polyketide hybrids containing a unique spiro[3.5]nonenyl moiety. Their trivial names, cryptolaevilactones G-L, follow those of the related known meroterpenoids cryptolaevilactones A-F. Cryptolaevilactone L (6) contains 11,12-cis-oriented substituents, while the other cryptolaevilactones contain trans-oriented groups. The structure of the linear δ-lactone 7, cryptolaevilactone M, was characterized from various spectroscopic data analysis, and the absolute configuration was determined by total synthesis through stereoselective allylation and Grubbs olefin metathesis. Compound 8 was elucidated to be an ionone derivative with a 3,4-syn-diol functionality.


Assuntos
Cryptocarya/química , Lactonas/química , Monoterpenos/química , Compostos de Espiro/química , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Folhas de Planta/química , Análise Espectral/métodos
3.
Cell Rep ; 26(4): 855-865.e5, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30673608

RESUMO

In plants, strigolactones are perceived by the dual receptor-hydrolase DWARF14 (D14). D14 belongs to the superfamily of α/ß hydrolases and is structurally similar to the karrikin receptor KARRIKIN INSENSITIVE 2 (KAI2). The moss Physcomitrella patens is an ideal model system for studying this receptor family, because it includes 11 highly related family members with unknown ligand specificity. We present the crystal structures of three Physcomitrella D14/KAI2-like proteins and describe a loop-based mechanism that leads to a permanent widening of the hydrophobic substrate gorge. We have identified protein clades that specifically perceive the karrikin KAR1 and the non-natural strigolactone isomer (-)-5-deoxystrigol in a highly stereoselective manner.


Assuntos
Bryopsida/enzimologia , Hidrolases/química , Lactonas/química , Proteínas de Plantas/química , Cristalografia por Raios X , Domínios Proteicos
4.
World J Gastroenterol ; 19(42): 7426-32, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24259974

RESUMO

AIM: To elucidate the characteristics of hemorrhagic gastric/duodenal ulcers in a post-earthquake period within one medical district. METHODS: Hemorrhagic gastric/duodenal ulcers in the Iwate Prefectural Kamaishi Hospital during the 6-mo period after the Great East Japan Earthquake Disaster were reviewed retrospectively. The subjects were 27 patients who visited our hospital with a chief complaint of hematemesis or hemorrhagic stool and were diagnosed as having hemorrhagic gastric/duodenal ulcers by upper gastrointestinal endoscopy during a 6-mo period starting on March 11, 2011. This period was divided into two phases: the acute stress phase, comprising the first month after the earthquake disaster, and the chronic stress phase, from the second through the sixth month. The following items were analyzed according to these phases: age, sex, sites and number of ulcers, peptic ulcer history, status of Helicobacter pylori (H. pylori) infection, intake of non-steroidal anti-inflammatory drugs, and degree of impact of the earthquake disaster. RESULTS: In the acute stress phase from 10 d to 1 mo after the disaster, the number of patients increased rapidly, with a nearly equal male-to-female ratio, and the rate of multiple ulcers was significantly higher than in the previous year (88.9% vs 25%, P < 0.005). In the chronic stress phase starting 1 mo after the earthquake disaster, the number of patients decreased to a level similar to that of the previous year. There were more male patients during this period, and many patients tended to have a solitary ulcer. All patients with duodenal ulcers found in the acute stress phase were negative for serum H. pylori antibodies, and this was significantly different from the previous year's positive rate of 75% (P < 0.05). CONCLUSION: Severe stress caused by an earthquake disaster may have affected the characteristics of hemorrhagic gastric/duodenal ulcers.


Assuntos
Desastres , Úlcera Duodenal/epidemiologia , Terremotos , Úlcera Péptica Hemorrágica/epidemiologia , Úlcera Gástrica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/efeitos adversos , Doença Crônica , Úlcera Duodenal/diagnóstico , Endoscopia Gastrointestinal , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Úlcera Péptica Hemorrágica/diagnóstico , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Úlcera Gástrica/diagnóstico , Estresse Psicológico/diagnóstico , Estresse Psicológico/epidemiologia , Fatores de Tempo
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