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A method for the selective construction of S-N/C(sp2)-S bonds using N-substituted O-thiocarbamates and indoles as substrates is reported. This protocol features good atom utilization, mild conditions, short reaction time, and wide substrate scope, which can provide a convenient path for the functionalization of indoles. In addition, the reaction could be scaled up on gram scale, showing potential application value in industry synthesis.
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At-home tooth whitening solutions with good efficacy and biosafety are highly desirable to meet the ever-growing demand for aesthetic dentistry. As a promising alternative to the classic peroxide bleaching that may damage tooth enamel and gums, piezocatalysis has been recently proposed to realize non-destructive whitening by toothbrushing with piezoelectrical particles. However, traditional particles either pose potential threats to human health or exhibit low piezoresponse to weak mechanical stimuli in the toothbrushing. Here, biocompatible and biodegradable polylactide particles constructed from interlocking crystalline lamellae have been hierarchically designed as next-generation whitening materials with ultra-high piezocatalytic activity and biosafety. By simultaneously controlling the chain conformation within lamellae and the porosity of such unique lamellae network at the nano- and microscales, the particles possessing unprecedented piezoelectricity have been successfully prepared due to the markedly increased dipole alignment, mechanical deformability, and specific surface area. The piezoelectric output can reach as high as 18.8 V, nearly 50 times higher than that of common solid polylactide particles. Consequently, their piezocatalytic effect can be readily activated by a toothbrush to rapidly clean the teeth stained with black tea and coffee, without causing detectable enamel damage. Furthermore, these particles have no cytotoxicity. This work presents a paradigm for achieving high piezoelectric activity in polylactide, which enables its practical application in tooth whitening.
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Clareamento Dental , Descoloração de Dente , Dente , Humanos , Contenção de Riscos Biológicos , Peróxido de HidrogênioRESUMO
By using glyoxylic acid monohydrate as a promoter, a wide range of substances containing a C-SO2 bond could be obtained from N-substituted maleimides or quinones and sodium sulfinates. The protocol features mild reaction conditions, short reaction time, and good atomic economics, which provides an alternative protocol for the α-sulfonylation of α,ß-unsaturated ketones.
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Bioassay-guided phytochemical investigation of the EtOAc fraction (ST-EtOAc) from the roots of Sophora tonkinensis resulted in the isolation of a new compound 6aR,11aR-1-hydroxy-4-isoprenyl-maackiain (1), along with 12 known compounds (2-13). The structure of the new compound was established by 1D and 2D NMR, MS data and circular dichroism analysis. Polyprenylated flavonoids 6-9 and 11-13 increased GLUT-4 translocation by the range of 1.35-2.75 folds. Sophoranone (8) exerted the strongest activity with 2.75 folds GLUT-4 translocation enhancement at the concentration of 10µM. This is the first report of the GLUT-4 translocation activity of the plant Sophora tonkinensis.
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Transportador de Glucose Tipo 4/metabolismo , Sophora/química , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Espectrometria de MassasRESUMO
Over the past two decades, biomass-derived and biodegradable polylactide (PLA) has sparked tremendous attention as a sustainable alternative to traditional petroleum-derived polymers for diverse applications. Unfortunately, the current applications of PLA have been mainly limited to biomedical and commodity fields, mostly because the poor heat resistance (resulting from low melting temperature) and hydrolysis stability make it hard to use as an engineering plastic. Stereocomplexation between enantiomeric poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) opens a new avenue toward PLA-based engineering plastics with improved properties. The formation, crystal structure, properties, and potential applications of stereocomplex-type PLA (SC-PLA) are summarized by some research groups. However, since it is challenging to achieve full stereocomplexation from high-molecular-weight PLLA/PDLA blends and to avoid serious thermal degradation of the PLAs after complete melting, the advances and progress in the processing of SC-PLA into useful products are quite rare in open publication. In this review, some important strategies for enhancing stereocomplex crystallization in practical processing operations are presented and recently developed processing technologies for SC-PLA are highlighted, such as low-temperature sintering. Furthermore, major challenges and future developments are briefly discussed. This review is expected to potentially open up new research activities in the processing of SC-PLA.
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Poliésteres/química , Polímeros/química , EstereoisomerismoRESUMO
Stereocomplex (SC) crystallization can prominently improve the physico-chemical properties of poly(l-lactide)/poly(d-lactide) (PLLA/PDLA) blends, yielding a novel polylactide (PLA) material. However, the predominant formation of SC crystals in the melt-processing of high-molar-mass (high-MW, >100 kg/mol) enantiomeric PLA blends remains a huge challenge due to the competition between SC crystallization and homocrystallization. Herein, double-grafted copolymer having both PLLA and PDLA side chain has been designed and synthesized as an efficient crystallization promoter for the harvest of SC crystals in the high-MW PLLA/PDLA blends. The results show that, with the addition of such a copolymer, the blends can preferentially crystallize into SC crystals in both isothermal and non-isothermal conditions. Promisingly, the SC crystals can be exclusively formed by adding only small amounts (e.g., 0.5 wt%) of the copolymer, without the formation of any homocrystals. This interesting observation can be interpreted by the crucial role of the unique copolymer in suppressing the phase separation of the opposite PLA enantiomers upon melting as an efficient compatibilizer and then encouraging the generation of alternatingly arranged PLLA/PDLA chain clusters favored for SC nucleation and crystal growth. These findings provide new inspiration for the development of high-performance PLA with desirable SC crystallizability.
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Poliésteres , Polímeros , Cristalização , Polímeros/química , Poliésteres/química , EstereoisomerismoRESUMO
The inadequacy of tactile perception systems in humanoid robotic manipulators limits the breadth of available robotic applications. Here, we designed a multifunctional flexible tactile sensor for robotic fingers that provides capabilities similar to those of human skin sensing modalities. This sensor utilizes a novel PI-MXene/SrTiO3 hybrid aerogel developed as a sensing unit with the additional abilities of electromagnetic transmission and thermal insulation to adapt to certain complex environments. Moreover, polyimide (PI) provides a high-strength skeleton, MXene realizes a pressure-sensing function, and MXene/SrTiO3 achieves both thermoelectric and infrared radiation response behaviors. Furthermore, via the pressure response mechanism and unsteady-state heat transfer, these aerogel-derived flexible sensors realize multimodal sensing and recognition capabilities with minimal cross-coupling. They can differentiate among 13 types of hardness and four types of material from objects with accuracies of 94% and 85%, respectively, using a decision tree algorithm. In addition, based on the infrared radiation-sensing function, a sensory array was assembled, and different shapes of objects were successfully recognized. These findings demonstrate that this PI-MXene/SrTiO3 aerogel provides a new concept for expanding the multifunctionality of flexible sensors such that the manipulator can more closely reach the tactile level of the human hand. This advancement reduces the difficulty of integrating humanoid robots and provides a new breadth of application scenarios for their possibility.
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Postoperative delirium (POD) is a frequent complication in geriatric patients with hip fractures, which is linked to poorer functional recovery, longer hospital stays, and higher short-and long-term mortality. Patients with increased age, preoperative cognitive impairment, comorbidities, perioperative polypharmacy, and delayed surgery are more prone to develop POD after hip fracture surgery. In this narrative review, we outlined the latest findings on postoperative delirium in geriatric patients with hip fractures, focusing on its pathophysiology, diagnosis, prevention, and treatment. Perioperative risk prediction, avoidance of certain medications, and orthogeriatric comprehensive care are all examples of effective interventions. Choices of anesthesia technique may not be associated with a significant difference in the incidence of postoperative delirium in geriatric patients with hip fractures. There are few pharmaceutical measures available for POD treatment. Dexmedetomidine and multimodal analgesia may be effective for managing postoperative delirium, and adverse complications should be considered when using antipsychotics. In conclusion, perioperative risk intervention based on orthogeriatric comprehensive care is the most effective strategy for preventing postoperative delirium in geriatric patients with hip fractures.
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Two new naphthalene derivatives, named naphthalene A (1) and naphthalene B (2), together with eight known compounds (3-10) were isolated from dichloromethane fraction of Phellinus igniarius. The structures of compounds were elucidated on the basis of spectroscopic analysis and absolute configurations were established based on electronic circular dichroism data. Compounds 9 and 10 exhibited moderate activity, increasing Glucose transporter 4 (GLUT-4) translocation by 1.62 and 1.87 folds, respectively.
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Fungos , Phellinus , NaftalenosRESUMO
Multi shape memory polymers (multi-SMPs) exhibit many potential applications such as aerospace, soft robotics, and biomedical devices because of their unique abilities. Although many works are done to broaden the preparations of multi-SMPs, the desire to a simple and versatile strategy as well as more complex shapes still exists. Moreover, a light-induced SMP shows more advantages than a thermal-induced one in many practical working circumstances. Herein, inspired by strong adhesion and efficient photothermal conversion of polydopamine (PDA) coating, we report a more simple and facile approach to prepare light-induced multi-SMPs by introducing a gradient PDA coating on a dual-SMP through time-controlled dipping. The photothermal converting properties with varying thicknesses of PDA under the tunable near-infrared light source are investigated. Then, light-induced multishape memory effects based on gradient PDA coatings are illustrated, where three designs of multi-SMPs - rectangle, triangle, and cross are prepared and demonstrated. Also, the evolutions of coating morphology during shape shifting are carefully studied. Finally, we present few complex designs of patterns and shapes as well as a design of potential application for the highly controllable smart devices. This strategy demonstrates a very simple and general strategy to design and prepare the light-induced multi-SMPs with complex shapes based on any thermal-responsive dual-SMPs.
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The title compound, 6,7-de-hydro-royleanone, C20H26O3 [systematic name: (4bS)-3-hy-droxy-2-isopropyl-4b,8,8-trimethyl-4b,5,6,7,8,8a-hexa-hydro-phenanthrene-1,4-dione] was isolated from Taxodium distichum (L.) Rich. The compound crystallizes in the space group P21. The crystal structure features two O-Hâ¯O hydrogen bonds, forming chains along the [010] direction.
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Eupatorium adenophorum Spreng. (EA) is a well-known noxious invasive species. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the essential oil derived from EA (EAEO) is mainly composed of sesquiterpenes. However, the pharmacological value of EAEO in hepatocellular carcinoma (HCC) remains largely unexplored. Herein, we investigated the anti-HCC activities of EAEO, and explored the potential mechanisms of EAEO-induced apoptosis. An MTT assay showed that EAEO inhibited HCC cell proliferation with little toxicity on normal liver cells. Wound healing and FACS assays revealed that EAEO suppressed HCC cell migration and arrested cell cycle, respectively. Moreover, EAEO promoted in vitro HCC cell apoptosis, and EAEO treatment inhibited HepG2 xenografts growth and enhanced apoptotic nucleus of xenografts in HepG2-bearing nude mice. Mechanistically, EAEO significantly decreased the ratio of Bcl-2/Bax and resulted in the activation of caspase-9 and -3. EAEO also reduced the expression of Grp78, which in turn relieved the inhibition of caspase-12 and -7. Meanwhile, EAEO suppressed the phosphorylation of STAT3 and AKT, indicative of its anti-HCC potential. In summary, we determined that EAEO treatment promoted HCC apoptosis via activation of the apoptotic signaling pathway in mitochondria and endoplasmic reticulum, as well as repressed the activity of STAT3 and AKT in HCC cells.
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The present study investigated the anti-diabetic activity and potential mechanisms of the polyphenol rich extract from Phellinus igniarius (PI-PRE) in vitro and in vivo. Four main phenolic compounds of PI-PRE were purified and identified as 7,8-dihydroxycoumarin, 3,4-dihydroxybenzalacetone, 7,3'-dihydroxy-5'-methoxyisoflavone and inoscavin C by the off-line semipreparative liquid chromatography-nuclear magnetic resonance protocol. In vitro, PI-PRE stimulated GLUT4 translocation by 2.34-fold and increased glucose uptake by 1.73-fold in L6 cells. However, the selective AMP-activated protein kinase (AMPK) inhibitor, compound C, completely reversed the PI-PRE-induced GLUT4 translocation. In vivo, KK-Ay mice treated with PI-PRE for four weeks had lower fasting blood glucose levels, as well as other blood-lipid indexes, compared with the vehicle control group. Mechanistic studies showed that the expressions of p-AMPKα and GLUT4 were significantly increased by treatment with PI-PRE in L6 cells. In KK-Ay mice, the expression of p-AMPKα was enhanced in the liver and skeletal muscle, and the expression of GLUT4 was increased in skeletal muscle. These findings suggest that PI-PRE possesses potential anti-diabetic effects including improving glucose tolerance, reducing hyperglycemia, and normalizing insulin levels. These effects are partly due to the activation of GLUT4 translocation via the modulation of the AMPK pathway.
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Basidiomycota/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Verduras/química , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Humanos , Hipoglicemiantes/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Extratos Vegetais/química , Polifenóis/químicaRESUMO
SCOPE: The number of people with diabetes is increasing rapidly in the world. In the present study, the hypoglycemic activity and potential mechanism of ergosterol (ERG), a phytosterol derived from the edible mushroom Pleurotus ostreatus are investigated in vitro and in vivo. METHODS AND RESULTS: ERG is isolated from Pleurotus ostreatus and identified by NMR spectra. The effects of ERG on the glucose uptake, glucose transporter 4 (GLUT4) translocation, GLUT4 expression, and the phosphorylation of AMPK, Akt and PKC in L6 cells are evaluated. ERG enhances glucose uptake and displays a GLUT4 translocation activity with up-regulating GLUT4 expression and phosphorylation of Akt and PKC in L6 cells. In vivo, antidiabetic activity of ERG is examined. The phosphorylation of Akt and PKC in different tissues from KK-Ay mice is assessed. ERG significantly improves insulin resistance and blood lipid indices while reducing fasting blood glucose levels and protecting pancreas and liver in the mice. Moreover, the phosphorylation of Akt and PKC is increased in different tissues. CONCLUSION: The results suggest that ERG may be a potential hypoglycemic agent for the treatment of T2DM with the probable mechanism of stimulating GLUT4 translocation and expression modulated by the PI3K/Akt pathway and PKC pathway.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Ergosterol/farmacologia , Hipoglicemiantes/farmacologia , Pleurotus/química , Animais , Glicemia/metabolismo , Linhagem Celular , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Transportador de Glucose Tipo 4/metabolismo , Masculino , Camundongos Mutantes , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RatosRESUMO
Kurarinone, a flavonoid isolated from Sophora flavescens Aiton, has been reported to have significant antitumor activity. However, the cytotoxic activity of kurarinone against non-small cell lung cancer (NSCLC) cells is still under explored. In our study, we have evaluated the inhibitory effects of kurarinone on the growth of NSCLC both in vivo and in vitro as well as the molecular mechanisms underlying kurarinone-induced A549 cell apoptosis. The results showed that kurarinone effectively inhibited the proliferation of A549 cells with little toxic effects on human bronchial epithelial cell line BEAS-2B. FASC examination and Hoechst 33258 staining assay showed that kurarinone dose-dependently provoked A549 cells apoptosis. Mechanistically, kurarinone significantly decreased the ratio of Bcl-2/Bax, thereby causing the activation of caspase 9 and caspase 3, and reduced the expression of Grp78, which led to relieve the inhibition of caspase-12 and caspase-7, as well as suppressing the activity of AKT. Meanwhile, modeling results from the Surflex-Dock program suggested that residue Ser473 of Akt is a potential binding site for kurarinone. In vivo, kurarinone inhibited the growth of A549 xenograft mouse models without apparent signs of toxicity. Our study indicated that kurarinone has the potential effects of anti-NSCLC, implemented through activating mitochondria apoptosis signaling pathway, as well as repressing the activity of endoplasmic reticulum pathway and AKT in A549 cells.
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The title compound, C20H28O4 [systematic name: (4bS,8aS,10S)-3,10-dihy-droxy-2-isopropyl-4b,8,8-trimethyl-4b,5,6,7,8,8a,9,10-octa-hydro-phenanthrene-1,4-dione], is an abietane-type diterpene, which was isolated from Taxodium ascendens (B.). The compound crystallizes in the chiral space group P21, but it was not possible to determine the absolute structure of the mol-ecule in the crystal by resonant scattering. The mol-ecular structure is stabilized by two intra-molecular O-Hâ¯O hydrogen bonds, enclosing S(5) and S(6) ring motifs. In the crystal, mol-ecules are linked by O-Hâ¯O and C-Hâ¯O hydrogen bonds, forming chains along the [010] direction. The crystal structure of the 10R stereoisomer of the title compound, isolated from the roots of Premna obtusifolia (Verbenaceae), has been reported. It crystallized in the chiral space group P212121, and the absolute structure was determined as (4bS,8aS,10R), by resonant scattering using Cu Kα radiation [Razak et al. (2010 â¸). Acta Cryst. E66, o1566-o1567].
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The title compound [systematic name: (4bS)-4-hy-droxy-2-isopropyl-4b,8,8-trimethyl-4b,5,6,7,8,8a-hexa-hydro-phenanthrene-3,9-dione], C20H26O3, is an abietane-type diterpene, which was isolated from Taxodium ascendens (B.). In the crystal, mol-ecules are linked by weak C-Hâ¯O hydrogen bonds, forming supra-molecular chains propagating along the [001] direction.
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The present study investigated the anti-diabetic activity and potential mechanism of stigmasterol (SMR), which is a kind of phytosterols derived from the edible soybean oil in vitro and in vivo. SMR displayed a mild GLUT4 translocation activity by 1.44-fold in L6 cells. L6 cells were treated with different concentration of SMR, showing significant effects on the enhancing glucose uptake. SMR administrated orally to the KK-Ay mice significantly alleviated their insulin resistance and oral glucose tolerance with reducing fasting blood-glucose levels and blood lipid indexes such as triglyceride and cholesterol. Moreover, the GLUT4 expression in L6 cells, skeletal muscle and white adipose tissue had been also enhanced. In this paper we conclude that, stigmasterol seems to have potential beneficial effects on the treatment of type 2 diabetes mellitus with the probable mechanism of targeting GLUT4 glucose transporter included increasing GLUT4 translocation and expression.
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To discover new bioactive compounds from nature plants, a primary screening of traditional Chinese medicines had been taken. The screening results showed that a EtOAc extract of Sedum sarmentosum displayed a certain degree of cytotoxic activity and bioassay-directed isolation of EtOAc extract gave two new megastigmanes, (6S,9R)-2-hydroxy-4-(2,6,6-trimethyl-4-oxo-cyclohex-2-enyl)-butyric acid (1) and (6S,9R)-2-hydroxy-4-(2,6,6-trimethyl-4-oxo-cyclohex-2-enyl)-butyric acid methyl ester (2) together with seven known flavonoids. The chemical structures of 1 and 2 were elucidated on the basis of detailed 1D, 2D NMR and MS data. When tested against HepG2 and Hep3B hepatocellular carcinoma cell lines, compounds 1-9 showed weak anti-HCC activity. In addition, in vitro antioxidant activities of 1-9 were evaluated by ABTS radical cation-scavenging assay. 1 and 2 exhibited weak activity with per micromoles equivalent to 0.039 and 0.042 µM of Trolox, respectively. The flavonoid component, quercetin (9) showed the highest antioxidant activities with per micromoles equivalent 0.67 µM of Trolox.
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Norisoprenoides/isolamento & purificação , Plantas Medicinais/química , Sedum/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Flavonoides/química , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Norisoprenoides/química , Extratos Vegetais/químicaRESUMO
This study was designed to explore the effects and mechanism of isoliensinine (isolie) from embryos of Nelumbo nucifera on type 2 diabetes and dyslipidemia in vivo and in vitro. The in vitro study showed that isolie increased the GLUT4 translocation by 2.5-fold in L6 cells. Furthermore, after 4 weeks of treatment, the in vivo biochemical study indexes revealed that isolie had a positive effect on decreasing serum insulin level (42.2 ± 5.10 vs 55.7 ± 6.33 mU/L, P < 0.05) and reducing fast blood glucose (9.4 ± 1.5 vs 18.7 ± 2.3 mmol/L, P < 0.001) and body weight (37.8 ± 2.9 vs 46.9 ± 5.4 g, P < 0.05) compared with the KK-Ay model mice. Isolie treatment led to significant increases in GLUT4 proteins (â¼2.7-fold in skeletal muscle and â¼2.4-fold in WAT) and phosphorylated AMP-activated protein kinase (â¼1.4-fold in skeletal muscle, â¼3.1-fold in WAT, and â¼2.3-fold in liver). However, isolie caused a significant decrease in lipogenesis protein expressions of PPARγ and SREBP-1c, and decreased the activity of ACC by increasing the phospho-ACC level. Our findings showed that isolie has the potential to alleviate type 2 diabetes associated with hyperlipidemia in KK-Ay mice. Regulation of GLUT4, SREBP-1c, PPARγ, AMPK phosphorylation, and ACC phosphorylation is implicated in the antidiabetic effects of isolie.