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Biomolecular piezoelectric materials show great potential in the field of wearable and implantable biomedical devices. Here, a self-assemble approach is developed to fabricating flexible ß-glycine piezoelectric nanofibers with interfacial polarization locked aligned crystal domains induced by Nb2CTx nanosheets. Acted as an effective nucleating agent, Nb2CTx nanosheets can induce glycine to crystallize from edges toward flat surfaces on its 2D crystal plane and form a distinctive eutectic structure within the nanoconfined space. The interfacial polarization locking formed between O atom on glycine and Nb atom on Nb2CTx is essential to align the ß-glycine crystal domains with (001) crystal plane intensity extremely improved. This ß-phase glycine/Nb2CTx nanofibers (Gly-Nb2C-NFs) exhibit fabulous mechanical flexibility with Young's modulus of 10 MPa, and an enhanced piezoelectric coefficient of 5.0 pC N-1 or piezoelectric voltage coefficient of 129 × 10-3Vm N-1. The interface polarization locking greatly improves the thermostability of ß-glycine before melting (≈210°C). A piezoelectric sensor based on this Gly-Nb2C-NFs is used for micro-vibration sensing in vivo in mice and exhibits excellent sensing ability. This strategy provides an effective approach for the regular crystallization modulation for glycine crystals, opening a new avenue toward the design of piezoelectric biomolecular materials induced by 2D materials.
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Activation of Ca2+-dependent TMEM16 scramblases induces phosphatidylserine externalization, a key step in multiple signaling processes. Current models suggest that the TMEM16s scramble lipids by deforming the membrane near a hydrophilic groove and that Ca2+ dependence arises from the different association of lipids with an open or closed groove. However, the molecular rearrangements underlying groove opening and how lipids reorganize outside the closed groove remain unknown. Here we directly visualize how lipids associate at the closed groove of Ca2+-bound fungal nhTMEM16 in nanodiscs using cryo-EM. Functional experiments pinpoint lipid-protein interaction sites critical for closed groove scrambling. Structural and functional analyses suggest groove opening entails the sequential appearance of two π-helical turns in the groove-lining TM6 helix and identify critical rearrangements. Finally, we show that the choice of scaffold protein and lipids affects the conformations of nhTMEM16 and their distribution, highlighting a key role of these factors in cryo-EM structure determination.
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The modified Nishida muscle transposition procedure, in which one-third of each vertical rectus muscle belly is sutured onto the sclera in the infero- and superotemporal quadrants without either tenotomy of the vertical rectus muscles or splitting of the vertical rectus muscle is an effective treatment for abducens nerve palsy. We report a case of inferior rectus muscle aplasia treated using the modified Nishida procedure to transpose both horizontal rectus muscles inferiorly combined with superior rectus tenotomy.
Subject(s)
Oculomotor Muscles , Ophthalmologic Surgical Procedures , Tenotomy , Humans , Oculomotor Muscles/surgery , Tenotomy/methods , Ophthalmologic Surgical Procedures/methods , Male , Abducens Nerve Diseases/surgery , Vision, Binocular/physiology , Suture Techniques , Female , Eye Movements/physiologyABSTRACT
Organosilane compounds are widely used in both organic synthesis and materials science. Particularly, 1,2-disilylated and gem-disilylated alkenes, characterized by a carbon-carbon double bond and multiple silyl groups, exhibit significant potential for subsequently diverse transformations. The versatility of these compounds renders them highly promising for applications in materials, enabling them to be valuable and versatile building blocks in organic synthesis. This review provides a comprehensive summary of methods for the preparation of cis/trans-1,2-disilylated and gem-disilylated alkenes. Despite notable advancements in this field, certain limitations persist, including challenges related to regioselectivity in the incorporation and chemoselectivity in the transformation of two nearly identical silyl groups. The primary objective of this review is to outline synthetic methodologies for the generation of these alkenes through disilylation reactions, employing silicon reagents, specifically disilanes, hydrosilanes, and silylborane reagents. The review places particular emphasis on investigating the practical applications of the C-Si bond of disilylalkenes and delves into an in-depth discussion of reaction mechanisms, particularly those reactions involving the activation of Si-Si, Si-H, and Si-B bonds, as well as the C-Si bond formation.
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Organochlorides are a crucial class of electrophiles in organic synthesis. Here, we present a protocol for the cross-electrophile coupling of aryl chlorides with unactivated alkyl chlorides, facilitated by an iron/B2pin2 catalytic system. We describe steps for the coupling of aryl chlorides with alkyl chlorides, followed by purification of products. This protocol can produce alkylated products with up to 81% yield. For complete details on the use and execution of this protocol, please refer to Zhang et al.1.
Subject(s)
Chlorides , Iron , Nickel , Molecular Structure , CatalysisABSTRACT
Introduction: Recent evidence suggests that blue-light phototherapy impacts gut microbiota composition in jaundiced newborns, leading to disturbances closely related to the therapy's side effects. As a result, gut microbiota may serve as a potential intervention target to mitigate these side effects. In this study, we aim to examine the effects of AB-GG (Lactobacillus rhamnosus LGG), Bb-12 (Bifidobacterium animalis Bb-12) and M-16V (Bifidobacterium breve M-16V) and their combination on the intestinal microbiota, metabolomics and phototherapy-related side effects in neonates with jaundice. Methods and analysis: A total of 100 jaundiced newborns aged two weeks or younger will be included in this randomized, single-blind (the parents knew, but the neonatologists did not know), single-center controlled trial to receive either 109 colony-forming units of AB-GG, Bb-12, M-16V, a combination of the three probiotics with blue-light phototherapy, or blue-light phototherapy alone. The experimental group will be treated with oral probiotics once daily for 30 days, while the control group will receive only blue-light phototherapy. The follow-up duration will last 30 days. The primary outcomes include changes in gut microbiota, metabolomics, and the incidence of phototherapy side effects, assessed after each phototherapy session, as well as on days 10, 20, and 30. Ethics and dissemination: The study protocol has been approved by the Ethics Committee of our institution. The findings of this trial will be submitted to a peer-reviewed pediatric journal. Its abstracts will be submitted to relevant national and international conferences. Clinical Trial Registration: http://www.chictr.org.cn/index.aspx, identifer (ChiCTR2000036013).
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Phospholipid scramblases mediate the rapid movement of lipids between membrane leaflets, a key step in establishing and maintaining membrane homeostasis of the membranes of all eukaryotic cells and their organelles. Thus, impairment of lipid scrambling can lead to a variety of pathologies. How scramblases catalyzed the transbilayer movement of lipids remains poorly understood. Despite the availability of direct structural information on three unrelated families of scramblases, the TMEM16s, the Xkrs, and ATG-9, a unifying mechanism has failed to emerge thus far. Among these, the most extensively studied and best understood are the Ca2+ activated TMEM16s, which comprise ion channels and/or scramblases. Early work supported the view that these proteins provided a hydrophilic, membrane-exposed groove through which the lipid headgroups could permeate. However, structural, and functional experiments have since challenged this mechanism, leading to the proposal that the TMEM16s distort and thin the membrane near the groove to facilitate lipid scrambling. Here, we review our understanding of the structural and mechanistic underpinnings of lipid scrambling by the TMEM16s and discuss how the different proposals account for the various experimental observations.
Subject(s)
Anoctamins , Phospholipid Transfer Proteins , Humans , Anoctamins/metabolism , Anoctamins/chemistry , Animals , Phospholipid Transfer Proteins/metabolism , Phospholipid Transfer Proteins/chemistryABSTRACT
Poly-L-lactic acid (PLLA), recognized as a piezoelectric material, not only demonstrates exceptional piezoelectric properties but also exhibits commendable biocompatibility and biodegradability. These properties render PLLA highly promising for diverse applications, including sensors, wearable devices, biomedical engineering, and related domains. This review offers a comprehensive overview of the distinctive piezoelectric effect of PLLA-based material and delves into the latest advancements in its preparation strategies as a piezoelectric material. It further presents recent research progress in PLLA-based piezoelectric materials, particularly in the realms of health monitoring, skin repair, nerve regeneration, and tissue repair. The discourse extends to providing insights into potential future trajectories for the development of PLLA-based piezoelectric materials.
Subject(s)
Biocompatible Materials , Polyesters , Polyesters/chemistry , Biocompatible Materials/chemistry , Humans , Animals , Tissue Engineering/methods , Wearable Electronic Devices , Biomedical Engineering/methodsABSTRACT
Phosphatidylserine externalization on the surface of dying cells is a key signal for their recognition and clearance by macrophages and is mediated by members of the X-Kell related (Xkr) protein family. Defective Xkr-mediated scrambling impairs clearance, leading to inflammation. It was proposed that activation of the Xkr4 apoptotic scramblase requires caspase cleavage, followed by dimerization and ligand binding. Here, using a combination of biochemical approaches we show that purified monomeric, full-length human Xkr4 (hXkr4) scrambles lipids. CryoEM imaging shows that hXkr4 adopts a novel conformation, where three conserved acidic residues create an electronegative surface embedded in the membrane. Molecular dynamics simulations show this conformation induces membrane thinning, which could promote scrambling. Thinning is ablated or reduced in conditions where scrambling is abolished or reduced. Our work provides insights into the molecular mechanisms of hXkr4 scrambling and suggests the ability to thin membranes might be a general property of active scramblases.
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Bionic electrical stimulation (Bio-ES) aims to achieve personalized therapy and proprioceptive adaptation by mimicking natural neural signatures of the body, while current Bio-ES devices are reliant on complex sensing and computational simulation systems, thus often limited by the low-fidelity of simulated electrical signals, and failure of interface information interaction due to the mechanical mismatch between soft tissues and rigid electrodes. Here, the study presents a flexible and ultrathin self-sustainable bioelectronic patch (Bio-patch), which can self-adhere to the lesion area of organs and generate bionic electrical signals synchronized vagal nerve envelope in situ to implement Bio-ES. It allows adaptive adjustment of intensity, frequency, and waveform of the Bio-ES to fully meet personalized needs of tissue regeneration based on real-time feedback from the vagal neural controlled organs. With this foundation, the Bio-patch can effectively intervene with excessive fibrosis and microvascular stasis during the natural healing process by regulating the polarization time of macrophages, promoting the reconstruction of the tissue-engineered structure, and accelerating the repair of damaged liver and kidney. This work develops a practical approach to realize biomimetic electronic modulation of the growth and development of soft organs only using a multifunctional Bio-patch, which establishes a new paradigm for precise bioelectronic medicine.
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Bioelectronic medicine is a rapidly growing field where targeted electrical signals can act as an adjunct or alternative to drugs to treat neurological disorders and diseases via stimulating the peripheral nervous system on demand. However, current existing strategies are limited by external battery requirements, and the injury and inflammation caused by the mechanical mismatch between rigid electrodes and soft nerves. Here we report a wireless, leadless, and battery-free ferroelectret implant, termed NeuroRing, that wraps around the target peripheral nerve and demonstrates high mechanical conformability to dynamic motion nerve tissue. As-fabricated NeuroRing can act as an ultrasound receiver that converts ultrasound vibrations into electrostimulation pulses, thus stimulating the targeted peripheral nerve on demand. This capability is demonstrated by the precise modulation of the sacral splanchnic nerve to treat colitis, providing a framework for future bioelectronic medicines that offer an alternative to non-specific pharmacological approaches.
Subject(s)
Nerve Tissue , Peripheral Nerves , Peripheral Nerves/physiology , Peripheral Nervous System , Electrodes , Prostheses and ImplantsABSTRACT
Objective:To investigate the effect of intrapartum artificial rupture of the membrane on maternal and infant outcomes among pregnant women infected with group B streptococcus (GBS).Methods:A total of 468 women with a singleton pregnancy who had a GBS infection were included in this case-control study. The enrolled women were divided into an artificial membrane rupture group ( n = 155) and a natural membrane rupture group ( n = 313) according to different methods of membrane rupture. Women in the artificial rupture of membrane group received antibiotic treatment after delivery or before membrane rupture, and the incidence of adverse pregnancy outcomes was compared between the two groups. Results:The incidences of chorioamnionitis, puerperal infection, and postpartum hemorrhage in the artificial membrane rupture group were 1.29% (2/155), 6.45% (10/155), and 4.52% (7/155), respectively, while those in the natural membrane rupture group were 1.92% (6/313), 3.83% (12/313), and 1.92% (6/313), respectively. There were no significant differences between the two groups in terms of incidence of chorioamnionitis, puerperal infection, or postpartum hemorrhage between the two groups ( χ2 = 0.01, 1.58, 1.72, all P > 0.05). The incidences of neonatal sepsis, neonatal asphyxia, neonatal GBS infection, and neonatal pneumonia in the artificial membrane rupture group were 0, 1.29% (2/155), 9.68% (15/155), and 0.65% (1/155), respectively, while those in the natural membrane rupture group were 1.60% (5/313), 0.64% (2/313), 11.82% (37/313), and 1.60% (5/313), respectively. There were no significant differences between the two groups in terms of neonatal sepsis, neonatal asphyxia, neonatal GBS infection, and neonatal pneumonia ( χ2 = 1.22, 0.03, 0.48, 0.18 both P > 0.05). Conclusion:Under the premise of effective antibiotic treatment, artificial rupture of membranes for pregnant women infected with GBS does not increase the incidence of adverse pregnancy outcomes. Artificial rupture of membranes technology can be used as an effective supplement to natural rupture of membranes.
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A foot trajectory control method is proposed for biomimetic robot.Compared with traditional methods,the method uses a single CPG neuron to directly apply the foot trajectory generated by the oscillator to the hexapod robot.The joint angles is solved reversely for realizing the rhythmic foot swing,thereby achieving lateral walking.The step distance and step amplitude in foot trajectory,and the forward and backward swing trajectories during the swing phase can be adjusted by setting the load factor,period,amplitude and other parameters in the CPG oscillator.The feasibility of applying the improved Hopf model to foot trajectory is verified through the joint simulation using Matlab and Coppeliasim.Compared with traditional methods,the improved model has high flexibility in parameter adjustment and performs well in concurrency processing.
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Objective To observe the value of ultrasonography for evaluating the anatomy and hemodynamic characteristics of vertebral artery course variation(VA-CV).Methods Totally 41 patients with VA-CV(VA-CV group)and 41 patients without VA-CV(control group)were enrolled.Lateral variation of vertebral artery(VA),the origin of V1 segment,the length of proximal subclavian artery(PSCA),the location of VA into the transverse foramen,the diameter of V2 segment,the peak systolic velocity(PSV)and the end-diastolic velocity(EDV)were evaluated with ultrasonography.The value of ultrasonography for evaluating VA-CV and relative hemodynamic changes were analyzed.Results Totally 49 variant VA were detected in VA-CV group,including 19 on the left and 30 on the right side,VA-CV on the right side was more often than on the left side.Seventeen(16 on the left and 1 on the right side)VA had abnormal origins,and abnormal VA origins on the left side were more than that on the right side(P<0.001).Meanwhile,VA origins of right VA-CV were mostly lower than that of the left side VA-CV(P<0.001).The length of right PSCA in VA-CA group was shorter than that in control group(P<0.05).More than half variant VA entered vertebral space from the transverse foramen of C5-6(33/49,67.35%),and the higher the entrance of transverse foramen,the shorter the PSCA(P<0.05).In VA-CV group,the diameter of V2 segment in left VA-CV patients was smaller than that in control group,while EDV in the former was lower than in the latter(both P<0.05).Conclusion Ultrasonography could be used to objectively evaluate VA-CV and relative hemodynamic changes.
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Objective To explore the relationship between the types of bicuspid aortic valves(BAV)and the outcome of functional mitral regurgitation(FMR)and the affecting factors of FMR.Methods From Jun 2018 to Sep 2022,patients with severe BAV aortic valve stenosis(AS)complicated with FMR underwent post transcatheter aortic valve replacement(TAVR)in Zhongshan Hospital,Fudan University were retrospectively analyzed.The baseline information and imaging data of different BAV patients were collected.Logistic regression was used to analyze the factors affecting the outcome of FMR(improvement and non-improvement).Result A total of 100 patients with TAVR were included,including 49 patients with type 0 of BAV and 51 patients with type 1 of BAV.Compared with patients of type 1,patients of type 0 had younger age[(72.78±6.09)y vs.(77.00±8.35)y,P=0.050],lower male ratio(47%vs.73%,P= 0.009)higher BMI[(23.19±2.62)kg/m2 vs.(21.99±3.13)kg/m2,P=0.041],and lower incidence of aortic regurgitation(69%vs.92%,P=0.040).Compared with the non-improvement group,the improvement group had a lower incidence of coronary heart disease(5%vs.18%,P=0.042),higher incidence of pulmonary hypertension(20%vs.2%,P=0.007),larger left ventricular diastolic diameter[(51.98±6.74)mm vs.(48.04±7.72)mm,P=0.009]and higher maximum flow velocity[(4.86±0.95)cm/s vs.(4.47±0.75)cm/s,P= 0.023]of the aortic valve.The results of Logistic regression analysis showed that preoperative pulmonary hypertension,left ventricular end-diastolic diameter and maximum valvular flow velocity of BAV patients were the potential affecting factors of FMR improvement after TAVR.Conclusion No significant difference was found in FMR improvement between BAV patients of type 0 and type 1 after TAVR.For BAV patients with AS,preoperative pulmonary hypertension,larger left ventricular end-diastolic diameter,and faster aortic valve flow velocity were associated with higher FMR improvement rate.
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Tricuspid regurgitation(TR)cases are widely distributed in China.Poor clinical drug efficacy,high surgical risk,and poor prognosis for right heart failure are found in patients with moderate or severe TR.In recent years,with the innovation of valve instruments and the development of technology,transcatheter tricuspid valve treatment could be a new choice for high-risk TR patients in surgery.Many TR animal models have emerged these years for the research of the mechanism of TR and for the clinical verification of instruments.Therefore,this review focuses on how to develop an animal model of TR and discusses the advantages and disadvantages of these techniques.
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Objective To analyze the frailty of patients with long-term maintenance dialysis(MD)and its influencing factors,and to explore the correlation of different dialysis modalities with the re-infection of novel coronavirus infection(COVID-19)and frailty syndrome.Methods Patients with regular dialysis in Nephrology Department of the Second Affiliated Hospital of Kunming Medical University from February to June 2023 were selected.A cross-sectional survey was conducted to collect clinical data of the patients,including dialysis modality(i.e.maintenance hemodialysis,abbreviated as hemodialysis,and continuous ambulatory peritoneal dialysis,abbreviated as peritoneal dialysis),and whether with re-infection of COVID-19.Patients were divided into 3 groups using Fried's frailty phenotype(FP):non-frailty group,pre-or-intermediate frailty group,and frailty syndrome group.The clinical characteristics of the FP were compared among the three groups.The correlation of frailty with clinical data,dialysis modality,re-infection of COVID-19 in each group was compared.Multifactorial logistic regression was used to analyze the factors influencing the development of frailty syndrome in patients.Results A total of 246 dialysis patients were included in this study,with 77(31.3%)in the non-frailty group,83(33.7%)in the pre-frailty group and 86(35.0%)in the frailty syndrome group.The frailty syndrome group showed characteristics of advanced age,high pre-dialysis creatinine level,low serum albumin level and combined pleural effusion(all P<0.05).There was no statistically significant difference in the comparison of frailty between the hemodialysis and peritoneal dialysis group(P = 0.960).COVID-19 re-positive patients had higher frailty score than non-re-positive patients.Multifactor logistic regression showed that age,COVID-19 re-infection of COVID-19,serum albumin,pre-dialysis creatinine,and pleural effusion were factors influencing the development of frailty syndrome in dialysis patients(P<0.05).Conclusion There is high incidence of frailty syndrome in dialysis patients,and there is no correlation of frailty with dialysis modality.High serum albumin level is a protective factor for the development of frailty syndrome in patients,whereas re-infection of COVID-19,advanced age,high pre-dialysis blood creatinine level and pleural effusion are risk factors for the development of frailty syndrome.
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Icariin,which belongs to the class of flavonoids,is the main active ingredient of the traditional tonic Chinese herb Epimedii Folium.Modern studies have shown that icariin has a wide range of effects on the male reproductive system.It has various pharmacological activities such as regulating cell proliferation and apoptosis,antioxidants,promoting testosterone secretion,improving erectile function,inhibiting prostate cancer cell migration,invasion,and regulating cell cycle.It has research value and application prospects in the field of urology and assisted reproduction.Therefore,Icariin's pharmacological effects and molecular mechanisms on the male reproductive system are reviewed in this paper combined with literature visualization analysis.It is expected to provide a theoretical basis for the therapeutic value development and application of icariin in male reproductive health.
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Objective To observe the clinical efficacy of Feisu Granules,and its effects on quality of life,coagulation and immune function in acute exacerbation of chronic obstructive pulmonary disease(AECOPD)with syndrome of phlegm-heat and blood stasis of lung.Methods Totally 120 AECOPD patients were divided into observation group and control group according to random number table method,with 60 cases in each group.The control group was given conventional Western medicine treatment,and the observation group received Feisu Granules treatment on the basis of the control group,one bag each time,three times a day,orally.The treatment for both groups lasted for 7 d.The clinical efficacy of both groups were observed.TCM symptom scores,St.George's respiratory questionnaire(SGRQ)score,coagulation function indexes(fibrinogen,D-dimer),and immune function indexes(CD4+,CD8+,CD4+/CD8+)of both groups were compared.The side effects were observed.Results The total effective rate in the observation group(93.10%)was significantly higher than that of the control group(79.66%),with statistical significance(P<0.05).Compared with before treatment,TCM symptom scores,scores of cough,wheezing,venous congestion,and SGRQ score decreased in both groups after treatment(P<0.05);after treatment,the observation group had lower above scores than the control group(P<0.05).Compared with before treatment,both groups showed a decrease in plasma fibrinogen and D-dimer levels after treatment(P<0.05);after treatment,the observation group showed lower levels of plasma fibrinogen and D-dimer compared with the control group(P<0.05).Compared with before treatment,the peripheral blood CD4+ and CD4+/CD8+ levels in both groups significantly increased after treatment,while CD8+ levels significantly decreased(P<0.05);after treatment,the peripheral blood CD4+ and CD4+/CD8+ in the observation group were higher than those in the control group,while CD8+ was lower than those in the control group(P<0.05).Neither group had any drug-related side effects.Conclusion On the basis of conventional Western medicine,the combination of Feisu Granules in the treatment of AECOPD with syndrome of phlegm-heat and blood stasis of lung can significantly improve clinical efficacy,improve patient quality of life,facilitate coagulation function recovery,and enhance cellular immune function.
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AIM To study the chemical constituents from the twigs of Aglaia perviridis Hiern and their total antioxidant and neuroprotective activities.METHODS The 95%ethanol extract from the twigs of A.perviridis were isolated and purified by silica gel,ODS and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antioxidant and neuroprotective activities were evaluated by T-AOC kit and MTT assay,respectively.RESULTS Twenty-one compounds were isolated and identified as 3-epicotillol(1),syringic acid(2),palmitic acid(3),di-N-pentyl phthalate(4),ethyl-4-hydroxyphenylacetate(5),7-hydroxy-6-methoxycoumarin(6),1-octanol(7),p-hydroxyphenylacetic acid(8),(+)-syringaresinol-4-O-β-D-glucopyranoside(9),(+)-episyring-4-O-β-D-glucopyranoside(10),methy-4-hydroxyphenylacetate(11),koaburaside(12),byzantionoside B(13),quercetin 3-O-α-L-rhamnopyranoside(14),(2R,3R)-(+)-glucodistylin(15),(2S,3S)-(-)-glucodistylin(16),(+)-lyoniresinol-3α-O-β-D-glucopyranoside(17),(+)-isolariciresinol-9'-O-β-D-glucopyranosidede(18),(-)-lyoniresinol-3α-O-β-D-glucopyranoside(19),phlorizin(20),β-sitosterol(21).The total antioxidant capacity of compounds2,9-10,14-20 was 10.300-38.367 U/(mmol·L-1).The neuroprotective effects of compounds 2,10 and 17 were concentration-dependent,and the optimal concentrations of compounds 9 and 15 were 50,100 μmol/L,respectively.CONCLUSION Compounds 1-20 are isolated from this plant for the first time.Compounds 2,9-10,14-20 have strong total antioxidant activities.Compounds 2,9-10,15,17 have neuroprotective activities.