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1.
Zhongguo Zhong Yao Za Zhi ; 48(18): 5024-5031, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37802844

RESUMO

Chemical constituents were isolated and purified from ethyl acetate fraction of Arctium lappa leaves by silica gel, ODS, MCI, and Sephadex LH-20 column chromatography. Their structures were identified with multiple spectroscopical methods including NMR, MS, IR, UV, and X-ray diffraction combined with literature data. Twenty compounds(1-20) were identified and their structures were determined as arctanol(1), citroside A(2), melitensin 15-O-ß-D-glucoside(3), 11ß,13-dihydroonopordopicrin(4), 11ß,13-dihydrosalonitenolide(5), 8α-hydroxy-ß-eudesmol(6), syringin(7), dihydrosyringin(8), 3,4,3',4'-tetrahydroxy-δ-truxinate(9),(+)-pinoresinol(10), phillygenin(11), syringaresinol(12), kaeperferol(13), quercetin(14), luteolin(15), hyperin(16), 4,5-O-dicaffeoylquinic acid(17), 1H-indole-3-carboxaldehyde(18), benzyl-ß-D-glucopyranoside(19), and N-(2'-phenylethyl) isobutyramide(20). Among them, compound 1 is a new norsesquiterpenoid, and compounds 2-5, 7-8, and 18-20 are isolated from this plant for the first time.


Assuntos
Arctium , Arctium/química , Espectroscopia de Ressonância Magnética , Luteolina/análise , Folhas de Planta/química
2.
J Phys Chem A ; 124(47): 9811-9817, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33179907

RESUMO

Tryptophan (Trp) is very necessary for biosystems; therefore, high-efficient detection of Trp is an important subject. Hereof, based on our early research works on fluorescent sensors, we rationally designed and synthesized a fluorescent sensor (SNP5) based on N-(2-aminoethyl)-2-(hexylthio) acetamide-functionalized pillar[5]arene, which showed high selectivity and sensitive recognition for l-Trp (LOD = 2.19 × 10-8 M). Moreover, SNP5 exhibited aggregation-induced emission enhancement fluorescence. Within SNP5, the pillar[5]arene group could act as N-H···π- and C-H···π-interaction sites, as well as a H-bond-interaction site; meanwhile, the N-(2-aminoethyl)-2-(hexylthio) acetamide group also served as a multihydrogen-bonding site. As a result, SNP5 could selectively detect l-Trp through the synergy of the pillar[5]arene group and the N-(2-aminoethyl)-2-(hexylthio) acetamide group. Compared with previous work, the results of this work support the strategy that changing the functionalized group of the pillar[5]arene can adjust the selectivity of the pillar[5]arene-based sensor and achieve the detection of different amino acids. The detection mechanism was specifically researched through experiments and theoretical calculations including frontier orbitals, electrostatic potential, and the independent gradient model approach. Interestingly, these theoretical calculations not only supported the experimental results but also provided a visualized understanding of guest-adaptive multisupramolecular interactions between SNP5 and l-Trp.


Assuntos
Calixarenos/química , Triptofano/análise , Acetamidas/química , Fluorescência , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Estrutura Molecular , Análise Espectral/métodos , Triptofano/química
3.
Soft Matter ; 15(33): 6753-6758, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31397832

RESUMO

In this study, a novel aggregation-induced emission supramolecular organic framework (AIE SOF) with ultrasensitive response, termed FSOF, was constructed using a tri-pillar[5]arene-based foldamer. Interestingly, benefiting from the noise signal shielding properties of FSOF as well as the competition between the cationπ and ππ interactions, the FSOF shows an ultrasensitive response for multi-analytes, such as Fe3+, Hg2+ and Cr3+. The limits of detection (LODs) of the FSOF for Fe3+, Hg2+ and Cr3+ are in the range of 9.40 × 10-10-1.86 × 10-9. More importantly, the xerogel of FSOF exhibits porous mesh structures, which could effect high-efficiency separation above metal ions from their aqueous solution, with adsorption percentages in the range 92.39-99.99%. In addition, by introducing metal ions into the FSOF, a series of metal ions coordinated supramolecular organic frameworks (MSOFs) were successfully constructed. Moreover, MSOFs show selective fluorescence "turn on" ultrasensitive detection CN- (LOD = 2.12 × 10-9) and H2PO4- (LOD = 1.78 × 10-9). This is a novel approach to construct SOFs through a tri-pillar[5]arene-based foldamer, and also provides a new way to achieve ultrasensitive detection and high-efficiency separation.

4.
Int J Mol Sci ; 19(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072674

RESUMO

Spinal cord injury (SCI) is a severe traumatic lesion of central nervous system (CNS) with only a limited number of restorative therapeutic options. Diosgenin glucoside (DG), a major bioactive ingredient of Trillium tschonoskii Max., possesses neuroprotective effects through its antioxidant and anti-apoptotic functions. In this study, we investigated the therapeutic benefit and underlying mechanisms of DG treatment in SCI. We found that in Sprague-Dawley rats with traumatic SCI, the expressions of autophagy marker Light Chain 3 (LC3) and Beclin1 were decreased with concomitant accumulation of autophagy substrate protein p62 and ubiquitinated proteins, indicating an impaired autophagic activity. DG treatment, however, significantly attenuated p62 expression and upregulated the Rheb/mTOR signaling pathway (evidenced as Ras homolog enriched in brain) due to the downregulation of miR-155-3p. We also observed significantly less tissue injury and edema in the DG-treated group, leading to appreciable functional recovery compared to that of the control group. Overall, the observed neuroprotection afforded by DG treatment warrants further investigation on its therapeutic potential in SCI.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Diosgenina/análogos & derivados , Glucosídeos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Traumatismos da Medula Espinal/prevenção & controle , Animais , Diosgenina/química , Diosgenina/uso terapêutico , Glucosídeos/química , MicroRNAs/genética , Fármacos Neuroprotetores/química , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Trillium/química
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 240: 118569, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32526401

RESUMO

L-Methionine (L-Met) is one of the essential amino acids in human health, efficiently detect L-Met is a significant issue. Herein, a concept "dual-site collaborative recognition" had been successfully introduced into the design and achieved high selective and sensitive recognition of L-Met. In order to realize the "dual-site collaborative recognition", we rationally designed and synthesized an ester functionalized pillar[5]arene-based fluorescent sensor (SP5). And it shows blue Aggregation-induced emission (AIE) fluorescence. In the SP5, the pillar[5]arene group act as C-H···π interactions site, and ester group serve as multi hydrogen bonding acceptor. Interestingly, the SP5 exhibited high selectivity and sensitivity (2.84 × 10-8 M) towards L-Met based on the collaboration of electron-rich cavernous pillar[5]arene group and ester group through C-H···π and H-bond interactions, respectively. This "dual-site collaborative recognition" mechanism has been investigated by 1H NMR, ESI-MS and theoretical calculation including frontier orbital (HOMO and LUMO), electrostatic potential (ESP) and the noncovalent interaction (NCI). These theoretical calculations not only support the proposed host-guest recognition mechanism, but also provided visualized information on the "dual-site collaborative recognition" mode. Furthermore, the concept "dual-site collaborative recognition" is an effective strategy for easily detecting biological molecules.


Assuntos
Calixarenos , Metionina , Humanos , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética
6.
Ultrason Sonochem ; 51: 350-358, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30385241

RESUMO

As a simple and effective physical method, ultrasound irradiation has been used to modify starch. Native waxy corn starch was treated by ultrasound irradiation at 100 and 400 W in this study. Compared with native waxy corn starch, lower proportion of B1, B2, and B3, higher proportion of A chain were observed in ultrasonicated waxy corn starch. 1H NMR combined with HPSEC-MALLS-RI data showed that lower degree of branching was observed in ultrasonicated waxy corn starch, and α-1,4 glycosidic linkages were more stable than α-1,6 glycosidic linkages in waxy corn starches. 13C NMR data indicated that the content of double helices was decreased, and single helix and amorphous components were increased after ultrasound irradiation. The A-type crystal structure was scarcely affected according to X-ray diffraction (XRD) analysis. The granule surface of ultrasonicated waxy corn starch became notch and rough fragment, and lower particle diameter was observed in ultrasonicated waxy corn starch. These results demonstrated that ultrasound irradiation affected chain length distribution, double helices, single helices and amorphous state, especially α-1,4 glycosidic linkages and α-1,6 glycosidic linkages, of waxy corn starch.

7.
J Agric Food Chem ; 65(39): 8744-8753, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28910527

RESUMO

In this study, the preparation and structural properties of spiral dextrin (SD)/vitamin E and SD/soy isoflavone inclusion complexes were studied. SD was obtained from debranched normal maize starch using isoamylases. After fractionation using a novel method of gradient ethanol precipitation, SD was separated into different fractions, among which SD-40 was found to be the optimal host molecule to prepare SD inclusion complexes with vitamin E or soy isoflavone. X-ray diffraction (XRD) and 13C cross-polarization magic angle spinning nuclear magnetic resonance (NMR) suggested that the crystalline structures of SD-40/vitamin E and SD-40/soy isoflavone were V6II and V6III types, respectively. Small-angle X-ray scattering revealed that the SD-40/vitamin E inclusion complex formed a tighter and more compact crystallite than the SD-40/soy isoflavone inclusion complex. Furthermore, the connection structures of inclusion complexes were investigated by two-dimensional nuclear Overhauser effect spectroscopy NMR, indicating that part of vitamin E with an alkyl chain was encapsulated in the helix cavity of SD-40, whereas the aromatic ring B of the soy isoflavone molecule was complexed by the helix cavity and screw of SD.


Assuntos
Dextrinas/química , Glycine max/química , Isoflavonas/química , Vitamina E/química , Cristalização , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Amido/química , Difração de Raios X , Zea mays/química
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(2): 305-6, 2009 Feb.
Artigo em Zh | MEDLINE | ID: mdl-19246307

RESUMO

OBJECTIVE: To investigate the association of microsurgical anatomy and growth of pituitary tumors with the recovery of visual pathway, and describe the intraoperative protection of the pituitary stalk and visual pathway. METHODS: A total of 113 patients undergoing pituitary tumor surgery were retrospectively analyzed, including 102 with visual disorder and 106 with pituitary dysfunction with the tumor size ranging from 1.9 to 6.8 cm. All the operations were performed via a transpterygoid approach or transfrontal approach. RESULTS: Radical resection of the tumors was performed in 86 cases, subtotal resection in 21 cases, and partial resection in 5 cases. After operation, 133 eyes showed vision improvement (77.8%), 29 showed no vision changes (17%) and 9 had deteriorated vision. Two patients died due to hypothalamic disorder and multiple organ failure. CONCLUSION: The arachnoid barrier between the pituitary tumor and visual pathway is an important structure for visual pathway protection during operation. Total separation of the tumor from the visual pathway allows total removal of the tumor. The preoperative localization and intraoperative identification of the pituitary stalk are critical for pituitary stalk protection.


Assuntos
Complicações Intraoperatórias/prevenção & controle , Microcirurgia/efeitos adversos , Hipófise/patologia , Neoplasias Hipofisárias/cirurgia , Vias Visuais/patologia , Adenoma/patologia , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Microcirurgia/métodos , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Neoplasias Hipofisárias/patologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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