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1.
Zhongguo Zhong Yao Za Zhi ; 43(11): 2261-2268, 2018 Jun.
Artículo en Zh | MEDLINE | ID: mdl-29945377

RESUMEN

In this study, complex enzymes combined with ultrasonic extraction technology(MC) were used, to select optimal extraction combinations by single factor and orthogonal test, with Hedysarum polysaccharides yield and content as the comprehensive indexes. The components, physicochemical properties and antioxidant activity of Hedysarum polysaccharides from complex enzyme combined with ultrasonic extraction(HPS-MC)and the Hedysarum polysaccharides from hot water extraction(HPS-R)were analyzed. The results showed that:complex enzymes had significant effect on the yield and content of Hedysarum polysaccharides, and the ultrasonic power could significantly improve the content of Hedysarum polysaccharides. The optimum technological parameters were as follows: complex enzyme ratio 1:1, ultrasonic power 105 W, ultrasonic time 60 min, and enzymatic hydrolysis pH 5, achieving (14.01±0.64)% and (92.45±1.47)% respectively for the yield and content of Polysaccharides. As compared with HPS-R, the molecular weight, absolute viscosity and protein content of HPS-MC were decreased, while the content of uronic acid was increased. In the antioxidant system, the concentration of polysaccharide was within the range of 1-7 g·L⁻¹; the antioxidant activity of HPS-MC was higher than that of HPS-R, and HPS-MC (80%) with the lowest molecular weight showed a significant dose effect relationship with the increase of the experimental concentration. In conclusion, MC is a simple, convenient, economical and environmentally friendly extraction technology, and the Hedysarum polysaccharides extracted by this method have obvious antioxidant activity.


Asunto(s)
Antioxidantes/farmacología , Fabaceae/química , Polisacáridos/farmacología , Enzimas , Hidrólisis , Peso Molecular , Extractos Vegetales , Ultrasonografía , Agua
2.
World J Clin Cases ; 12(10): 1799-1803, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38660075

RESUMEN

BACKGROUND: The precise mechanism by which severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impacts the central nervous system remains unclear, with manifestations spanning from mild symptoms (e.g., olfactory and gustatory deficits, hallucinations, and headache) to severe complications (e.g., stroke, seizures, encephalitis, and neurally demyelinating lesions). The occurrence of single-pass subdural effusion, as described below, is extremely rare. CASE SUMMARY: A 56-year-old male patient presented with left-sided limb weakness and slurred speech as predominant clinical symptoms. Through comprehensive imaging and diagnostic assessments, he was diagnosed with cerebral infarction complicated by hemorrhagic transformation affecting the right frontal, temporal, and parietal regions. In addition, an intracranial infection with SARS-CoV-2 was identified during the rehabilitation process; consequently, an idiopathic subdural effusion developed. Remarkably, the subdural effusion underwent absorption within 6 d, with no recurrence observed during the 3-month follow-up. CONCLUSION: Subdural effusion is a potentially rare intracranial complication associated with SARS-CoV-2 infection.

3.
Dalton Trans ; 51(24): 9397-9403, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35674199

RESUMEN

Luminescent metal-organic frameworks (MOFs) have garnered considerable attention in various fields. Herein, we proposed a hierarchical confinement strategy based on MOF-on-MOF to tune luminescence emission ranging from blue to red including white light in a flexible way. The easily available ZIF-8 MOF was used as a host for the confinement of two kinds of size-matching dyes (perylene and rhodamine B) to obtain a layered ZIF-8@dye@ZIF-8@dye via in situ encapsulation and seed-mediated synthesis. ZIF-8@dye@ZIF-8@dye materials with different fluorescence emission in dispersed and solid states were both obtained by tuning the initial encapsulation concentration of dye and changing the structure of the inner and outer ZIF-8@dye layers. To our delight, ZIF-8@0.125perylene@ZIF-8@25RhB with white light emission in the dispersed state was obtained; meanwhile, ZIF-8@0.125perylene + 25RhB and mechanically mixed ZIF-8@0.125perylene + ZIF-8@25RhB could not realize white light emission under the same conditions, indicating that the proposed hierarchical confinement strategy facilitated white light regulation. Similarly, the emission of ZIF-8@dye@ZIF-8@dye in the solid state has also been investigated; ZIF-8@perylene@ZIF-8@3RhB with white light emission was obtained, while white light emission could not be achieved in ZIF-8@perylene + 3RhB and ZIF-8@perylene + ZIF-8@3RhB, which further indicated the importance of the hierarchical confinement strategy based on MOF-on-MOF. The proposed hierarchical confinement strategy may also inspire the development of other functional optical MOF materials.

4.
ACS Appl Mater Interfaces ; 14(47): 53359-53369, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36383092

RESUMEN

Construction of color-tunable luminescent polymeric materials with enhanced emission intensity and room-temperature phosphorescence (RTP) performance regulated by a single chromophore component is highly desirable in the scope of photoluminescent materials. Herein, a set of binary copolymers were facilely synthesized using free radical polymerization by selecting different types of polymer matrix and N-substituted naphthalimides (NPA) as chromophores. Surprisingly, the fluorescence emission of copolymers could be remarkably enhanced, because of the intramolecular aggregation of NPA manipulated by a single polymer chain in both solution and solid state. Moreover, RTP signals of binary copolymers were all clearly observed in the air without any processing procedure, because of the embedding of phosphors into hydrogen bonding networks after copolymerization with vinyl-based acrylamide monomers. Taking advantages of the synergistic effect of copolymerization-induced aggregation and copolymerization-induced rigidification to promote optical performance, UV stimulus-responsive luminescent polymer films with processability, flexibility, and adjustable emission wavelength were simply prepared using a drop-casting method in large scale, the setting of which is the basis for application in the fields of organic optoelectronics, information security, and bioimaging/sensing.

5.
ACS Appl Mater Interfaces ; 14(40): 45669-45678, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36174061

RESUMEN

Integrating metal-organic framework (MOF)-covalent organic framework (COF) allows versatile engineering of hybrid materials with properties superior to pristine components, especially COFs suffered from aggregation-caused quenching (ACQ), unlocking more possibilities to improve the luminescence of COFs. In this work, we prepared various MOF@COF composites with different COF layer thicknesses, in which stable UiO-66-NH2 served as the inner substrate and 1,3,5-benzenetricarboxaldehyde (BT), and 3,3'-dihydroxybenzidine (DH) were used to construct a COF layer. In addition to the conventional preparation method, we increased the ratio of BT and DH to be 1:2.5, and impressively, the morphologies of acquired UC (1:2.5) materials were quite different from the previous reticular structure and gradually extended from the spherical structure to the prickly structure with the increase of COF monomers. Remarkably, all of the UC materials possessed better luminescence properties than individual COF due to the limited COF layers. Meanwhile, UC-1 materials with an optimal COF layer displayed the strongest emission. In comparison with a single COF, the quantum yields of UC-1 and UC-1 (1:2.5) were increased nearly 7 times and 5 times, respectively. Moreover, the fluorescence of UC-1 materials was progressively enhanced via selective F- sensing. This work is expected to shed light on the potential hybridization of MOF-COF with structural adjustment, morphological design, and luminescence enhancement.

6.
J Agric Food Chem ; 69(14): 4081-4092, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33787231

RESUMEN

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is an effective target for green herbicide discovery. In this work, we reported the unexpected discovery of a novel series of N-phenylaminomethylthioacetylpyrimidine-2,4-diones (2-6) as promising PPO inhibitors based on investigating the reaction intermediates of our initially designed N-phenyluracil thiazolidinone (1). An efficient one-pot procedure that gave 41 target compounds in good to high yields was developed. Systematic Nicotiana tabacum PPO (NtPPO) inhibitory and herbicidal activity evaluations led to identifying some compounds with improved NtPPO inhibition potency than saflufenacil and good post-emergence herbicidal activity at 37.5-150 g of ai/ha. Among these analogues, ethyl 2-((((2-chloro-4-fluoro-5-(3-methyl-2,6-dioxo-4-(trifluoromethyl)-3,6-dihydropyrimidin-1(2H)-yl)phenyl)amino)methyl)thio)acetate (2c) (Ki = 11 nM), exhibited excellent weed control at 37.5-150 g of ai/ha and was safe for rice at 150 g of ai/ha, indicating that compound 2c has the potential to be developed as a new herbicide for weed management in paddy fields. Additionally, our molecular simulation and metabolism studies showed that the side chains of compound 2c could form a hydrogen-bond-mediated seven-membered ring system; substituting a methyl group at R1 could reinforce the hydrogen bond of the ring system and reduce the metabolic rate of target compounds in planta.


Asunto(s)
Inhibidores Enzimáticos , Herbicidas , Inhibidores Enzimáticos/farmacología , Herbicidas/farmacología , Protoporfirinógeno-Oxidasa , Nicotiana , Control de Malezas
7.
J Pharm Anal ; 9(4): 266-273, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31452965

RESUMEN

The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.

8.
J Agric Food Chem ; 67(33): 9254-9264, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31356740

RESUMEN

In continuation of our search for potent protoporphyrinogen IX oxidase (PPO, EC 1.3.3.4) inhibitors, we designed and synthesized a series of novel herbicidal cycloalka[d]quinazoline-2,4-dione-benzoxazinones. The bioassay results of these synthesized compounds indicated that most of the compounds exhibited very strong Nicotiana tabacum PPO (NtPPO) inhibition activity. More than half of the 37 synthesized compounds displayed over 80% control of all three tested broadleaf weeds at 37.5-150 g ai/ha by postemergent application, and a majority of them showed no phytotoxicity toward at least one kind of crop at 150 g ai/ha. Promisingly, 17i (Ki = 6.7 nM) was 6 and 4 times more potent than flumioxazin (Ki = 46 nM) and trifludimoxazin (Ki = 31 nM), respectively. Moreover, 17i displayed excellent, broad-spectrum herbicidal activity, even at levels as low as 37.5 g ai/ha, and it was determined to be safe for wheat at 150 g ai/ha in postemergent application, indicating the great potential for 17i development as a herbicide for weed control in wheat fields.


Asunto(s)
Benzoxazinas/química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Herbicidas/química , Herbicidas/farmacología , Proteínas de Plantas/antagonistas & inhibidores , Protoporfirinógeno-Oxidasa/antagonistas & inhibidores , Quinazolinas/química , Benzoxazinas/farmacología , Diseño de Fármacos , Cinética , Proteínas de Plantas/química , Malezas/efectos de los fármacos , Malezas/enzimología , Protoporfirinógeno-Oxidasa/química , Relación Estructura-Actividad Cuantitativa , Quinazolinas/farmacología , Nicotiana/efectos de los fármacos , Nicotiana/enzimología , Control de Malezas
9.
Acta Biomater ; 7(4): 1665-73, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21130904

RESUMEN

This paper demonstrates a general approach for fabrication of lactobionic chitosan microcapsules using layer-by-layer assembly via click chemistry. Chitosan was selectively modified with either azide (CHI-Az) or alkyne (CHI-Alk) groups. The growth of the CHI-Az/CHI-Alk click multilayer was studied experimentally by multilayer assembly on planar supports. Linear buildup of the film was observed. The chitosan click capsules were also analyzed with confocal laser scanning microscopy and transmission electron microscopy. Capsules were found to have regular spherical shapes. In addition, (CHI-Az/CHI-Alk)-coated particles were modified with fluorescein isothiocyanate to ensure that the particles can be easily post-functionalized. Finally, lactobionic acid was conjugated onto the (CHI-Az/CHI-Alk)-coated particles and the lactobionic particles exhibited hepatoma cell (HepG2) targeting behavior.


Asunto(s)
Quitosano/química , Química Clic/métodos , Disacáridos/química , Portadores de Fármacos/química , Hígado/metabolismo , Alquinos/química , Azidas/química , Carbonato de Calcio/farmacología , Cápsulas , Adhesión Celular/efectos de los fármacos , Quitosano/síntesis química , Fluoresceína-5-Isotiocianato/metabolismo , Células Hep G2 , Humanos , Hígado/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Microscopía Confocal , Microscopía Electrónica de Transmisión , Especificidad de Órganos/efectos de los fármacos , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
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