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1.
Front Psychol ; 12: 828894, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35095705

RESUMEN

Due to the arrival of positive psychology (PP) in the development of teaching, the construct of engagement has been thrived and got a notable function in the educational arena. Alternatively, numerous individual differences, containing ambiguity of tolerance, have been taken into consideration as a result of the key role they can play in the process of learning, and thus, on different facets of the learners' engagement. Furthermore, resilience is recommended to be an alternate and effective way of engaging English as a foreign language (EFL) learners. Also, it is a significant feature of the human adaptation system in which students can efficaciously manage and tackle stressful involvements despite their troubles and disasters. Given the eminence of both ambiguity tolerance and resilience in educational settings and the fact that little attention has been given to these constructs in foreign language learning, the present review makes an effort to scrutinize the impact of ambiguity of tolerance and resilience on EFL learners' engagement. Succinctly, the fundamental roles of ambiguity tolerance and resilience in learners' engagement were confirmed, and consistent with the conclusions drawn from the present review, some suggestions are set forth concerning the implications of this paper.

2.
J Nat Prod ; 78(8): 1816-22, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26230970

RESUMEN

Five new compounds, pinazaphilones A and B (1, 2), two phenolic compounds (4, 5), and penicidone D (6), together with the known Sch 1385568 (3), (±)-penifupyrone (7), 3-O-methylfunicone (8), 5-methylbenzene-1,3-diol (9), and 2,4-dihydroxy-6-methylbenzoic acid (10) were obtained from the culture of the endophytic fungus Penicillium sp. HN29-3B1, which was isolated from a fresh branch of the mangrove plant Cerbera manghas collected from the South China Sea. Their structures were determined by analysis of 1D and 2D NMR and mass spectroscopic data. Structures of compounds 4 and 7 were further confirmed by a single-crystal X-ray diffraction experiment using Cu Kα radiation. The absolute configurations of compounds 1-3 were assigned by quantum chemical calculations of the electronic circular dichroic spectra. Compounds 2, 3, 5, and 7 inhibited α-glucosidase with IC50 values of 28.0, 16.6, 2.2, and 14.4 µM, respectively, and are thus more potent than the positive control, acarbose.


Asunto(s)
Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/farmacología , Penicillium/química , Policétidos/aislamiento & purificación , Policétidos/farmacología , Benzopiranos/farmacología , Cristalografía por Rayos X , Medicamentos Herbarios Chinos , Inhibidores de Glicósido Hidrolasas/química , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Policétidos/química , Rhizophoraceae/microbiología , alfa-Glucosidasas/efectos de los fármacos
3.
Mar Drugs ; 13(5): 3091-102, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25996099

RESUMEN

Chemical investigation of the endophytic fungus Aspergillus sp. 16-5B cultured on Czapek's medium led to the isolation of four new metabolites, aspergifuranone (1), isocoumarin derivatives (±) 2 and (±) 3, and (R)-3-demethylpurpurester A (4), together with the known purpurester B (5) and pestaphthalides A (6). Their structures were determined by analysis of 1D and 2D NMR spectroscopic data. The absolute configuration of Compound 1 was determined by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra, and that of Compound 4 was revealed by comparing its optical rotation data and CD with those of the literature. The structure of Compound 6 was further confirmed by single-crystal X-ray diffraction experiment using CuKα radiation. All isolated compounds were evaluated for their α-glucosidase inhibitory activities, and Compound 1 showed significant inhibitory activity with IC50 value of 9.05 ± 0.60 µM. Kinetic analysis showed that Compound 1 was a noncompetitive inhibitor of α-glucosidase. Compounds 2 and 6 exhibited moderate inhibitory activities.


Asunto(s)
Aspergillus/química , Aspergillus/metabolismo , Cristalografía por Rayos X/métodos , Isocumarinas/química , Isocumarinas/metabolismo , Cinética , Espectroscopía de Resonancia Magnética/métodos , Difracción de Rayos X/métodos , alfa-Glucosidasas/metabolismo
4.
Planta Med ; 80(11): 912-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25116120

RESUMEN

Three new vermistatin derivatives, 6-demethylpenisimplicissin (1), 5'-hydroxypenisimplicissin (2), and 2''-epihydroxydihydrovermistatin (3), along with five known vermistatin analogues, methoxyvermistatin (4), vermistatin (5), 6-demethylvermistatin (6), hydroxyvermistatin (7), and penisimplicissin (8), were isolated from the culture of the mangrove endophytic fungus Penicillium sp. HN29-3B1 from Cerbera manghas. Their structures were elucidated mainly by nuclear magnetic resonance spectroscopy. The absolute configurations of compounds 1 and 2 were deduced on the basis of circular dichroism data. The absolute structures of compounds 3 and 5 were confirmed by a single-crystal X-ray diffraction experiment using Cu Kα radiation. In the bioactivity assay, compounds 1 and 3 exhibited α-glucosidase inhibitory activity with IC50 values of 9.5 ± 1.2 and 8.0 ± 1.5 µM, respectively. The plausible biosynthetic pathways for all compounds are discussed.


Asunto(s)
Apocynaceae/microbiología , Inhibidores de Glicósido Hidrolasas/farmacología , Penicillium/química , Pironas/farmacología , Endófitos , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Estructura Molecular , Pironas/química , Pironas/aislamiento & purificación , Difracción de Rayos X , alfa-Glucosidasas/efectos de los fármacos
5.
Mar Drugs ; 12(6): 3669-80, 2014 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-24955555

RESUMEN

Two new sulfur-containing benzofuran derivatives, eurothiocin A and B (1 and 2), along with five known compounds, zinniol (3), butyrolactone I (4), aspernolide D (5), vermistatin (6), and methoxyvermistatin (7), were isolated from the cultures of Eurotium rubrum SH-823, a fungus obtained from a Sarcophyton sp. soft coral collected from the South China Sea. The new compounds (1 and 2) share a methyl thiolester moiety, which is quite rare among natural secondary metabolites. The structures of these metabolites were assigned on the basis of detailed spectroscopic analysis. The absolute configurations of 1 and 2 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) data. Compounds 1 and 2 exhibited more potent inhibitory effects against α-glucosidase activity than the clinical α-glucosidase inhibitor acarbose. Further mechanistic analysis showed that both of them exhibited competitive inhibition characteristics.


Asunto(s)
Antozoos/microbiología , Benzofuranos/farmacología , Eurotium/metabolismo , Inhibidores de Glicósido Hidrolasas/farmacología , Acarbosa/farmacología , Animales , Benzofuranos/química , Benzofuranos/aislamiento & purificación , China , Dicroismo Circular , Eurotium/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Océanos y Mares , Análisis Espectral , alfa-Glucosidasas/efectos de los fármacos , alfa-Glucosidasas/metabolismo
6.
Mar Drugs ; 12(5): 2953-69, 2014 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-24840716

RESUMEN

A new alterporriol-type anthranoid dimer, alterporriol S (1), along with seven known anthraquinone derivatives, (+)-aS-alterporriol C (2), hydroxybostrycin (3), halorosellinia A (4), tetrahydrobostrycin (5), 9α-hydroxydihydrodesoxybostrycin (6), austrocortinin (7) and 6-methylquinizarin (8), were isolated from the culture broth of the mangrove fungus, Alternaria sp. (SK11), from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods, including 1D and 2D NMR spectra. The absolute configurations of 1 and the axial configuration of 2 were defined by experimental and theoretical ECD spectroscopy. 1 was identified as the first member of alterporriols consisting of a unique C-10-C-2' linkage. Atropisomer 2 exhibited strong inhibitory activity against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with an IC50 value 8.70 µM.


Asunto(s)
Alternaria/química , Antraquinonas/química , Antraquinonas/farmacología , Antituberculosos/química , Antituberculosos/farmacología , Avicennia/microbiología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Fermentación , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Conformación Molecular , Mycobacterium tuberculosis/efectos de los fármacos
7.
J Nat Prod ; 77(4): 800-6, 2014 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-24597756

RESUMEN

A pair of unusual benzannulated 6,6-spiroketal enantiomers [(-)-1 and (+)-1] and three new biogenetically related compounds (2-4), together with two known related analogues (5 and 6), have been isolated from a mangrove fungus, Penicillium dipodomyicola HN4-3A. Their structures were elucidated on the basis of spectroscopic analysis (1D and 2D NMR data) and X-ray crystallography. The absolute configurations of enantiomers (-)-1 and (+)-1 were determined using quantum chemical calculations of the electronic circular dichroic (ECD) spectra. Compounds 2 and 3 exhibited strong inhibitory activity against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with IC50 values of 0.16±0.02 and 1.37±0.05 µM, respectively.


Asunto(s)
Mycobacterium tuberculosis/efectos de los fármacos , Penicillium/química , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Rhizophoraceae/microbiología , Compuestos de Espiro/aislamiento & purificación , Compuestos de Espiro/farmacología , China , Cristalografía por Rayos X , Concentración 50 Inhibidora , Conformación Molecular , Estructura Molecular , Mycobacterium tuberculosis/enzimología , Resonancia Magnética Nuclear Biomolecular , Compuestos de Espiro/química , Estereoisomerismo
8.
Zhonghua Yi Xue Za Zhi ; 86(1): 39-41, 2006 Jan 03.
Artículo en Chino | MEDLINE | ID: mdl-16606534

RESUMEN

OBJECTIVE: To investigate the etiology, diagnosis, and management of spontaneous perirenal hemorrhage (SPH). METHODS: The clinical data of 35 patients, 10 males and 12 females, aged 35.9 (12-77), with the diagnosis of SPH, without history of trauma, anticoagulant use, dialysis, and renal transplantation, were analyzed. RESULTS: The underlying disease of SPH included angiomyolipoma (18 cases), renal cell carcinoma (7 cases), kidney cyst (2 cases), renal artery aneurysm (3 cases), rupture of renal artery aneurysm accompanied with pregnancy (2 cases), renal pheochromocytoma (3 cases 2 of which accompanied with pregnancy), congenital stricture of pelvic ureter junction (1 case), and liver cancer (1 case). The most common underlying diseases were nephrogenic (96%) with angiomyolipoma ranking first (54%) followed by renal cell carcinoma (21%). The underlying diseases were diagnosed correctly in 23 cases (69%). CT helped in diagnosis of 34 cases. Surgery was performed on most of the cases. CONCLUSION: The most common causes of SPH is renal neoplasms more than 50% of which are benign. Renal artery aneurysm and pheochromocytoma tend to rupture during pregnancy. CT is the first method of choice in diagnosis.


Asunto(s)
Hemorragia/diagnóstico por imagen , Hemorragia/terapia , Enfermedades Renales/diagnóstico por imagen , Enfermedades Renales/terapia , Adolescente , Adulto , Anciano , Aneurisma/complicaciones , Angiografía de Substracción Digital , Angiomiolipoma/complicaciones , Anticoagulantes/uso terapéutico , Niño , Femenino , Hemorragia/etiología , Humanos , Enfermedades Renales/etiología , Neoplasias Renales/complicaciones , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Embarazo , Arteria Renal/patología , Diálisis Renal , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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