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1.
Chem Pharm Bull (Tokyo) ; 69(6): 526-528, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34078798

RESUMEN

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.


Asunto(s)
Compuestos de Boro/química , Colorantes Fluorescentes/química , NAD/química , Azúcares/análisis , Compuestos de Boro/síntesis química , Colorantes Fluorescentes/síntesis química , Estructura Molecular , Fenómenos Ópticos
2.
J Nat Prod ; 82(9): 2368-2378, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31442048

RESUMEN

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.


Asunto(s)
Cryptocarya/química , Lactonas/química , Monoterpenos/química , Compuestos de Espiro/química , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Humanos , Estructura Molecular , Hojas de la Planta/química , Análisis Espectral/métodos
3.
Cell Rep ; 26(4): 855-865.e5, 2019 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-30673608

RESUMEN

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.


Asunto(s)
Bryopsida/enzimología , Hidrolasas/química , Lactonas/química , Proteínas de Plantas/química , Cristalografía por Rayos X , Dominios Proteicos
4.
World J Gastroenterol ; 19(42): 7426-32, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24259974

RESUMEN

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.


Asunto(s)
Desastres , Úlcera Duodenal/epidemiología , Terremotos , Úlcera Péptica Hemorrágica/epidemiología , Úlcera Gástrica/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antiinflamatorios no Esteroideos/efectos adversos , Enfermedad Crónica , Úlcera Duodenal/diagnóstico , Endoscopía Gastrointestinal , Femenino , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Humanos , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/diagnóstico , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Úlcera Gástrica/diagnóstico , Estrés Psicológico/diagnóstico , Estrés Psicológico/epidemiología , Factores de Tiempo
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