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1.
Small ; : e2403292, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958094

RESUMO

Antimony selenide (Sb2Se3) has sparked significant interest in high-efficiency photovoltaic applications due to its advantageous material and optoelectronic properties. In recent years, there has been considerable development in this area. Nonetheless, defects and suboptimal [hk0] crystal orientation expressively limit further device efficiency enhancement. This study used Zinc (Zn) to adjust the interfacial energy band and strengthen carrier transport. For the first time, it is discovered that the diffusion of Zn in the cadmium sulfide (CdS) buffer layer can affect the crystalline orientation of the Sb2Se3 thin films in the superstrate structure. The effect of Zn diffusion on the morphology of Sb2Se3 thin films with CdxZn1-xS buffer layer has been investigated in detail. Additionally, Zn doping promotes forming Sb2Se3 thin films with the desired [hk1] orientation, resulting in denser and larger grain sizes which will eventually regulate the defect density. Finally, based on the energy band structure and high-quality Sb2Se3 thin films, this study achieves a champion power conversion efficiency (PCE) of 8.76%, with a VOC of 458 mV, a JSC of 28.13 mA cm-2, and an FF of 67.85%. Overall, this study explores the growth mechanism of Sb2Se3 thin films, which can lead to further improvements in the efficiency of Sb2Se3 solar cells.

2.
Molecules ; 27(3)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35163984

RESUMO

Flavanols, a common class of secondary plant metabolites, exhibit several beneficial health properties by acting as antioxidant, anticarcinogen, cardioprotective, anti-microbial, anti-viral, and neuroprotective agents. Furthermore, some flavanols are considered functional ingredients in dairy products. Based on their structural features and health-promoting functions, flavanols have gained the attention of pharmacologists and botanists worldwide. This review collects and summarizes 121 flavanols comprising four categories: flavan-3-ols, flavan-4-ols, isoflavan-4-ols, and flavan-3,4-ols. The research of the various structural features and pharmacological activities of flavanols and their derivatives aims to lay the groundwork for subsequent research and expect to provide mentality and inspiration for the research. The current study provides a starting point for further research and development.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Cardiotônicos/farmacologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Compostos Fitoquímicos/farmacologia , Humanos
3.
Molecules ; 26(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069700

RESUMO

Plants from the Chrysanthemum genus are rich sources of chemical diversity and, in recent years, have been the focus of research on natural products chemistry. Sesquiterpenoids are one of the major classes of chemical constituents reported from this genus. To date, more than 135 sesquiterpenoids have been isolated and identified from the whole genus. These include 26 germacrane-type, 26 eudesmane-type, 64 guaianolide-type, 4 bisabolane-type, and 15 other-type sesquiterpenoids. Pharmacological studies have proven the biological potential of sesquiterpenoids isolated from Chrysanthemum species, reporting anti-inflammatory, antibacterial, antitumor, insecticidal, and antiviral activities for these interesting molecules. In this paper, we provide information on the chemistry and bioactivity of sesquiterpenoids obtained from the Chrysanthemum genus which could be used as the scientific basis for their future development and utilization.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Chrysanthemum/química , Inseticidas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Anti-Infecciosos/química , Anti-Inflamatórios/química , Antineoplásicos Fitogênicos/química , Vias Biossintéticas , Humanos , Inseticidas/química
4.
Small ; 16(17): e2000909, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32249500

RESUMO

Various organic nanoagents have been developed for photothermal therapy (PTT) and photodynamic therapy (PDT) under near-infrared (NIR) irradiation. Among them, small molecule-based nanoagents are very attractive due to their advantages of well-defined chemical structures, high purity, good reproducibility, and easy processability. However, only a few small molecule-based nanoagents have been developed for PDT under NIR irradiation. Moreover, the mechanism of PDT under NIR is still elusive. Herein, a semiconducting small molecule (BTA) with donor-acceptor-donor structure and twisted conformation is developed for PDT/PTT under NIR irradiation. A large π-conjugated electron-deficient unit is used as the core to couple with two electron-donating units, ensuring the strong absorption under 808 nm. Moreover, the donor-acceptor structures and twisted conformation can reduce the energy gap between the singlet and triplet states (∆EST ) to afford effective intersystem crossing, beneficial for reactive oxygen species generation. The mechanism is probed by experimental and theoretical evidence. Moreover, the BTA nanoparticles exhibit excellent biocompatibility and PTT/PDT in vitro performance under NIR irradiation. This provides a strategy for designing highly efficient PDT/PTT molecular materials.


Assuntos
Nanopartículas , Fotoquimioterapia , Terapia Fototérmica , Semicondutores , Raios Infravermelhos , Fotoquimioterapia/métodos , Terapia Fototérmica/métodos
5.
Small ; 14(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29171927

RESUMO

Black phosphorus nanobelts are fabricated with a one-step solid-liquid-solid reaction method under ambient pressure, where red phosphorus is used as the precursor instead of white phosphorus. The thickness of the as-fabricated nanobelts ranges from micrometers to tens of nanometers as studied by scanning electron microscopy. Energy dispersive X-ray spectroscopy and X-ray diffraction indicate that the nanobelts have the composition and the structure of black phosphorus, transmission electron microscopy reveals a typical layered structure stacked along the b-axis, and scanning transmission electron microscopy with energy dispersive X-ray spectroscopy analysis demonstrates the doping of bismuth into the black phosphorus structure. The nanobelt can be directly measured in scanning tunneling microscopy in ambient conditions.

6.
Sensors (Basel) ; 18(5)2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29751538

RESUMO

In this paper, a sequential multiplicative extended Kalman filter (SMEKF) is proposed for attitude estimation using vector observations. In the proposed SMEKF, each of the vector observations is processed sequentially to update the attitude, which can make the measurement model linearization more accurate for the next vector observation. This is the main difference to Murrell’s variation of the MEKF, which does not update the attitude estimate during the sequential procedure. Meanwhile, the covariance is updated after all the vector observations have been processed, which is used to account for the special characteristics of the reset operation necessary for the attitude update. This is the main difference to the traditional sequential EKF, which updates the state covariance at each step of the sequential procedure. The numerical simulation study demonstrates that the proposed SMEKF has more consistent and accurate performance in a wide range of initial estimate errors compared to the MEKF and its traditional sequential forms.

7.
Chem Biodivers ; 14(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28963759

RESUMO

Two new flavones, 6,7-methylenedioxy-4-hydroxypeltogynan-7'-one (1), cochliophilin B (2), as well as two known ones, cochliophilin A (3) and 6-methoxy-7-hydroxy flavone (4), were isolated from the ethanol extract of the root of Phytolacca acinosa Roxb. Compound 1 is a flavanol framework with one δ-lactone unit, which is rather rare in nature. The structures of the new compounds were determined on the basis of extensive spectroscopic (IR, MS, 1D- and 2D-NMR) analyses, the absolute configuration of 1 was established by comparing experimental and calculated electronic circular dichroism spectra. The structures of known compounds were fixed by comparison with literatures data. Compounds 2 and 4 showed modest inhibitory activities against BEL-7402 cell line, with IC50 values of 28.22 and 39.16 µmol/L, respectively.


Assuntos
Flavonas/química , Phytolacca/química , Células A549 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flavonas/isolamento & purificação , Flavonas/toxicidade , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Phytolacca/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Espectrofotometria Infravermelho
8.
Int J Clin Pharmacol Ther ; 53(11): 923-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26308171

RESUMO

BACKGROUND: Statins have been reported to exert anti-inflammatory effects, but the association between statins and acute lung injury (ALI) remains controversial. Thus, we performed a meta-analysis of all published randomized controlled trials (RCTs) aiming to summarize and evaluate the current evidence about the potential use of statins in ALI patients. METHOD: We searched for articles that focused on the association between statins and ALI-related outcomes through electronic databases until December 10th, 2014. The inclusion of articles, quality appraisal of included studies, and data extraction were performed by two investigators. Eligible articles were analyzed by Review manager 5.2 and STATA 12.0 software. RESULTS: Data from 1,778 patients in five randomized controlled clinical trials were analyzed. No differences in intensive care unit (ICU) mortality (RR=0.88, 95% CI=0.63-1.22, p=0.44), hospital mortality (RR=1.00, 95% CI=0.85-1.17, p=0.97) and mechanical ventilation duration (MD=-0.40, 95% CI=-1.52-0.71, p=0.48) were observed between the experimental and control groups. CONCLUSIONS: According to large and high-quality published clinical trials as also summarized by the present meta-analysis, there is insufficient evidence to support the use of statins in ALI patients.


Assuntos
Lesão Pulmonar Aguda/terapia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Respiração Artificial , Lesão Pulmonar Aguda/diagnóstico , Lesão Pulmonar Aguda/mortalidade , Distribuição de Qui-Quadrado , Mortalidade Hospitalar , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial/efeitos adversos , Respiração Artificial/mortalidade , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
9.
Angew Chem Int Ed Engl ; 53(35): 9284-8, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-24989824

RESUMO

An efficient and convenient synthesis of α-allyl cyclic amidines has been achieved by applying a novel cascade reaction. Copper(I)-mediated in situ N-sulfonyl ketenimine formation from the reaction of a terminal alkyne with sulfonyl azide is followed by an intramolecular nucleophilic attack on the central carbon atom by an allylic tertiary amine, and then an aza-Claisen rearrangement takes place through a chair transition state to furnish the titled amidines with complete stereocontrol.

10.
Foods ; 13(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611314

RESUMO

LC-MS is widely utilized in identifying and tracing plant-derived food varieties but quality control markers screening and accurate identification remain challenging. The adulteration and confusion of Chrysanthemum flowers highlight the need for robust quality control markers. This study established an efficient workflow by integrating UHPLC-Orbitrap-MS/MS with Compound Discoverer and chemometrics. This workflow enabled the systematic screening of 21 markers from 10,540 molecular features, which effectively discriminated Chrysanthemum flowers of different species and cultivars. The workflow incorporated targeted and untargeted methods by employing diagnostic product ions, fragmentation patterns, mzCloud, mzVault, and in-house databases to identify 206 compounds in the flowers, including 17 screened markers. This approach improved identification accuracy by reducing false positives, eliminating in-source fragmentation interference, and incorporating partial verification utilizing our established compound bank. Practically, this workflow can be instrumental in quality control, geolocation determination, and varietal tracing of Chrysanthemum flowers, offering prospective use in other plant-derived foods.

11.
Adv Healthc Mater ; 13(13): e2303802, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38341630

RESUMO

Hydrogel is a very promising dressing for hemostasis and wound healing due to its good adhesion and long-term moist environment. However, secondary injury caused by tissue adhesion due to homogeneous hydrogel cannot be ignored. The obvious interface existing in Janus hydrogel will weaken its asymmetric function. Here, a hierarchical adhesive polyacrylic acid-polyurushiol water-oil Janus hydrogel (JPs@PAA-PU) without adhesive layer is fabricated by one-pot method in the stabilization of polystyrene@silica-siliver Janus particles (JPs). The morphological structure, mechanical properties, anisotropic chemical composition, and adhesion performance, in vivo, and in vitro hemostatic properties of Janus hydrogel are investigated. Result shows that the obtained Janus hydrogel possesses obvious compartmentalization in microstructure, functional groups, and chemical elements. Janus hydrogel is provided with asymmetric interfacial toughness with top 52.45 ± 2.29 Kpa and bottom 7.04 ± 0.88 Kpa on porcine liver. The adhesion properties of PAA side to tissue, red blood cells and platelets, promoting effect of PU side on coagulation cascade reaction and its physical battier endow Janus hydrogel with shorter hemostatic time and less blood loss than control group. It also exhibits excellent antibacterial effects against Escherichia coli and Staphylococcus aureus (>90%). Janus hydrogel possesses biosafety, providing safety guarantee for clinical applications in the future.


Assuntos
Resinas Acrílicas , Hidrogéis , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Resinas Acrílicas/química , Escherichia coli/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Suínos , Hemostáticos/química , Hemostáticos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Camundongos , Antibacterianos/química , Antibacterianos/farmacologia
12.
J Phys Chem Lett ; 15(9): 2301-2310, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38386516

RESUMO

The brain's function can be dynamically reconfigured through a unified neuron-synapse architecture, enabling task-adaptive network-level topology for energy-efficient learning and inferencing. Here, we demonstrate an organic neuristor utilizing a ferroelectric-electrolyte dielectric interface. This neuristor enables tunable short- to long-term plasticity and reconfigurable logic-in-memory functions by controlling the interfacial interaction between electrolyte ions and ferroelectric dipoles. Notably, the short-term plasticity of the organic neuristor allows for power-efficient reservoir computing in edge-computing scenarios, exhibiting impressive recognition accuracy, including images (90.6%) and acoustic signals (97.7%). For high-performance computing tasks, the neuristor based on long-term plasticity and logic-in-memory operations can construct all of the hardware circuits of a binarized neural network (BNN) within a unified framework. The BNN demonstrates excellent noise tolerance, achieving high recognition accuracies of 99.2% and 86.4% on the MNIST and CIFAR-10 data sets, respectively. Consequently, our research sheds light on the development of power-efficient artificial intelligence systems.

13.
Scand J Infect Dis ; 45(12): 891-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24024759

RESUMO

BACKGROUND: Correct dosing of antimicrobial drugs in septic patients receiving continuous renal replacement therapy (CRRT) is complex. This study aimed to evaluate the effects of dosing adjustments performed by pharmacists on the length of intensive care unit (ICU) stay, ICU cost, and antimicrobial adverse drug events (ADEs). METHODS: A single-center, 2-phase (pre-/post-intervention) study was performed in an ICU of a university-affiliated hospital. Septic patients receiving CRRT in the post-intervention phase received a specialized antimicrobial dosing service from critical care pharmacists, whereas patients in the pre-intervention phase received routine medical care without involving pharmacists. The 2 phases were compared to evaluate the outcomes of pharmacist interventions. RESULTS: Pharmacists made 183 antimicrobial dosing adjustment recommendations for septic patients receiving CRRT. Changes in CRRT-related variables (116, 63.4%) were the most common risk factors for dosing errors, and ß-lactams (101, 55.2%) were the antimicrobials most commonly associated with dosing errors. Dosing adjustments were related to a reduced length of ICU stay from 10.7 ± 11.1 days to 7.7 ± 8.3 days (p = 0.037) in the intervention group, and to cost savings of $3525 (13,463 ± 12,045 vs. 9938 ± 8811, p = 0.038) per septic patient receiving CRRT in the ICU. Suspected antimicrobial adverse drug events in the intervention group were significantly fewer than in the pre-intervention group (19 events vs. 8 events, p = 0.048). CONCLUSIONS: The involvement of pharmacists in antimicrobial dosing adjustments in septic patients receiving CRRT is associated with a reduced length of ICU stay, lower ICU costs, and fewer ADEs. Hospitals may consider employing clinical pharmacists in ICUs.


Assuntos
Anti-Infecciosos/administração & dosagem , Cuidados Críticos/métodos , Farmacêuticos , Terapia de Substituição Renal/métodos , Sepse/tratamento farmacológico , Adulto , Idoso , Anti-Infecciosos/efeitos adversos , Cuidados Críticos/economia , Cuidados Críticos/normas , Feminino , Humanos , Masculino , Erros de Medicação/prevenção & controle , Pessoa de Meia-Idade
14.
RSC Adv ; 13(13): 8847-8862, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36936846

RESUMO

Gentianae Macrophyllae Radix, the dried root of Gentiana macrophylla Pall., Gentiana crassicaulis Duthie ex Burk., Gentiana straminea Maxim., or Gentiana dahurica Fisch., is a traditional Chinese medicine with multi-origins and some adulterants. Liquid chromatography coupled to electrostatic orbitrap high-resolution mass spectrometry (LC-Orbitrap-MS) was used to search the different components of Gentianae Macrophyllae Radix of the four species. High-performance liquid chromatography (HPLC) combined with fingerprint analysis, principal components analysis (PCA), and partial least-squares discrimination analysis (PLS-DA) was also utilized to distinguish them and their adulterants based on the critical components identified by LC-MS. A single standard to determine the multi-components (SSDMC) method was established for the determination of the critical markers. A total of 93 compounds were identified from Gentianae Macrophyllae Radix, including 58 common ones. Their HPLC fingerprints show a significant difference with the adulterants. In addition, PCA and PLS-DA could make a distinction among the four species. Loganic acid, 6'-O-ß-d-glucosylgentiopicroside, swertiamarine, gentiopicroside, and sweroside were identified as the critical markers and then quantified by the SSDMC method. The developed strategy is powerful for the quality control and authentication of Gentianae Macrophyllae Radix.

15.
Biosensors (Basel) ; 13(10)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37887102

RESUMO

With the innovation of wearable technology and the rapid development of biosensors, wearable biosensors based on flexible textile materials have become a hot topic. Such textile-based wearable biosensors promote the development of health monitoring, motion detection and medical management, and they have become an important support tool for human healthcare monitoring. Textile-based wearable biosensors not only non-invasively monitor various physiological indicators of the human body in real time, but they also provide accurate feedback of individual health information. This review examines the recent research progress of fabric-based wearable biosensors. Moreover, materials, detection principles and fabrication methods for textile-based wearable biosensors are introduced. In addition, the applications of biosensors in monitoring vital signs and detecting body fluids are also presented. Finally, we also discuss several challenges faced by textile-based wearable biosensors and the direction of future development.


Assuntos
Técnicas Biossensoriais , Líquidos Corporais , Dispositivos Eletrônicos Vestíveis , Humanos , Técnicas Biossensoriais/métodos , Atenção à Saúde , Têxteis , Monitorização Fisiológica/métodos
16.
Food Chem X ; 20: 101010, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144808

RESUMO

The unripe fruit or peel of Citrus aurantium L., Citrus sinensis Osbeck, and Citrus reticulata Blanco are often disregarded due to perceptions of their marginal value. The present study was undertaken to explore the differences in phytochemical composition and bioactive properties of five citrus by-products in China and demonstrate their potential value. 214 compounds were systematically identified using LC-Orbitrap-MS analysis. Among them, narirutin, naringin, hesperidin, and neohesperidin were established as essential compounds for the discrimination and authentication of the five by-products via a combination of LC-MS, HPLC, and TLC techniques. Variations in the antioxidant activity of the by-products were observed, which correlated with their maturity and were attributable to differences in their active ingredients. Moreover, spectrum-effect relationship analysis revealed that the four previously identified differential markers, along with nobiletin and tangeretin, significantly contributed to the differences in antioxidant activity. The results highlight the potential for citrus by-product enhancement and utilization.

17.
Biodivers Data J ; 11: e98143, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327372

RESUMO

There are a large number of microorganisms in the gut of insects, which form a symbiotic relationship with the host during the long-term co-evolution process and have a significant impact on the host's nutrition, physiology, development, immunity, stress tolerance and other aspects. However, the composition of the gut microbes of Hyphantriacunea remains unclear. In order to investigate the difference and diversity of intestinal microbiota of H.cunea larvae feeding on different host plants, we used PacBio sequencing technology for the first time to sequence the 16S rRNA full-length gene of the intestinal microbiota of H.cunea. The species classification, ß diversity and function of intestinal microflora of the 5th instar larvae of four species of H.cunea feeding on apricot, plum, redbud and Chinese ash were analysed. The results showed that a total of nine phyla and 65 genera were identified by PacBio sequencing, amongst which Firmicutes was the dominant phylum and Enterococcus was the dominant genus, with an average relative abundance of 59.29% and 52.16%, respectively. PERMANOVA analysis and cluster heat map showed that the intestinal microbiomes of H.cunea larvae, fed on different hosts, were significantly different. LEfSe analysis confirmed the effect of host diet on intestinal community structure and PICRUSt2 analysis showed that most of the predictive functions were closely related to material transport and synthetic, metabolic and cellular processes. The results of this study laid a foundation for revealing the interaction between the intestinal microorganisms of H.cunea and its hosts and provided ideas for exploring new green prevention and control strategies of H.cunea.

18.
Adv Sci (Weinh) ; 10(31): e2304246, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37691096

RESUMO

The efficiency of antimony selenide (Sb2 Se3 ) solar cells is still limited by significant interface and deep-level defects, in addition to carrier recombination at the back contact surface. This paper investigates the use of lithium (Li) ions as dopant for Sb2 Se3 films, using lithium hydroxide (LiOH) as a dopant medium. Surprisingly, the LiOH solution not only reacts at the back surface of the Sb2 Se3 film but also penetrate inside the film along the (Sb4 Se6 )n molecular chain. First, the Li ions modify the grain boundary's carrier type and create an electric field between p-type grain interiors and n-type grain boundary. Second, a gradient band structure is formed along the vertical direction with the diffusion of Li ions. Third, carrier collection and transport are improved at the surface between Sb2 Se3 and the Au layer due to the reaction between the film and alkaline solution. Additionally, the diffusion of Li ions increases the crystallinity, orientation, surface evenness, and optical electricity. Ultimately, the efficiency of Sb2 Se3 solar cells is improved to 7.57% due to the enhanced carrier extraction, transport, and collection, as well as the reduction of carrier recombination and deep defect density. This efficiency is also a record for CdS/Sb2 Se3 solar cells fabricated by rapid thermal evaporation.

19.
Front Chem ; 10: 878811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620653

RESUMO

A pair of 3,4-seco-cycloartane triterpenoid isomers with a rare peroxy bridge, namely, xuetonins A and B (1 and 2), four new lignans xuetonlignans A-D (3-6), a new sesquiterpene xuetonpene (7), and a new natural product xuetonin C (8), along with 43 known compounds, were obtained from the leaves of Tujia ethnomedicine, Kadsura heteroclita. Their structures and configurations were determined with the help of a combination of 1D- and 2D-NMR, HRESIMS spectra, electronic circular dichroism (ECD), and X-ray diffraction data. Compounds 2, 10, 13-15, and 17-19 showed moderate-to-potent activity against rheumatoid arthritis fibroblast-like synoviocytes (RAFLS) with IC50 values of 19.81 ± 0.26, 12.73 ± 0.29, 5.70 ± 0.24, 9.25 ± 0.79, 5.66 ± 0.52, 11.91 ± 0.44, 13.22 ± 0.27, and 15.94 ± 0.36 µM, respectively. Furthermore, compounds 22, 25, and 31 exhibited significant hepatoprotective effects against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells at 10 µM, and the cell viability increased by 12.93, 25.23, and 13.91%, respectively, compared with that in the model group (cf. bicyclol, 12.60%).

20.
Front Chem ; 10: 911201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755263

RESUMO

Six new bibenzyls (three pairs of enantiomers), bletstrins D-F (1-3), were isolated from the ethyl acetate-soluble (EtOAc) extract of tubers of Bletilla striata (Thunb.) Rchb f. Their structures, including absolute configurations, were determined by 1D/2D NMR spectroscopy, optical rotation value, and experimental electronic circular dichroism (ECD) data analyses, respectively. Compounds 1-3 possess a hydroxyl-substituted chiral center on the aliphatic bibenzyl bridge, which represented the first examples of natural bibenzyl enantiomers from the genus of Bletilla. The antibacterial, antitumor necrosis factor (anti-TNF-α), and neuroprotective effects of the isolates have been evaluated. Compounds 3a and 3b were effective against three Gram-positive bacteria with minimum inhibitory concentrations (MICs) of 52-105 µg/ml. Compounds 2a and 2b exhibited significant inhibitory effects on TNF-α-mediated cytotoxicity in L929 cells with IC50 values of 25.7 ± 2.3 µM and 21.7 ± 1.7 µM, respectively. Subsequently, the possible anti-TNF-α mechanism of 2 was investigated by molecular docking simulation. Furthermore, the neuroprotective activities were tested on the H2O2-induced PC12 cell injury model, and compounds 2b, 3a, and 3b (10 µM) could obviously protect the cells with the cell viabilities of 57.86 ± 2.08%, 64.82 ± 2.84%, and 64.11 ± 2.52%, respectively.

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