Biochanin A,as the Lrg1/TGF-β/Smad2 pathway blockade,attenuates blood-brain barrier damage after cerebral ischemiareperfusion by modulating leukocyte migration patterns

Background:Biochanin A is an excellent dietary isoflavone that has the concomitant function of both medicine and foodstuff.The attenuation function of biochanin A on blood-brain barrier(BBB)damage induced by cerebral ischemia-reperfusion remains unclear.Methods:C57BL/6 mice were subjected to 1 h middle cerebral artery occlusion(MCAO)followed by 24 h reperfusion.The infarct volume of the brain was stained by TTC,while leakage of the brain was quantitatively stained by Evans blue,and the neurologic deficit score was measured.Microglial-induced morphologic changes were observed via immunofluorescence staining,and rolling and adhering leukocytes in venules were observed via two-photon imaging,while the inner fluorescein isothiocyanate-albumin of venules were compared with those of surrounding interstitial area through venular albumin leakage.Results:The attenuation effect of biochanin A on tight junction injury was compared in ischemia-reperfusion mice or conventional knockdown of leucine-richα2-glycoprotein 1(Lrg1)mice.Biochanin A could ameliorate BBB injury in mice with cerebral ischemiareperfusion in a dose-dependent manner by strengthening the immunostaining volume of occludin,claudin-5,and zonula occludens-1.The amoeba morphologic changes of microglial combined with the elevated expression of Lrg1 could be relieved under the treatment of biochanin A.Biochanin A played a countervailing role on the rolling leukocytes in the vessel,while the leakage of blood vessels was reduced.Biochanin A diminished its functions to further improved attenuation for tight junction injury on conventional Lrg1-knockout mice,as well as the inhibition effects on TGF-β1,and the phosphorylation of suppressor of mothers against decapentaplegic 2(Smad2)/Smad2 via western blot assay.Conclusion:Biochanin A could alleviate tight junction injury induced by cerebral ischemiareperfusion and blocked the Lrg1/TGF-β/Smad2 pathway to modulate leukocyte migration patterns.

Analysis of the personalized treatment and the relevant prognostic factors in children with medulloblastoma

Purpose:The present study summarized cases of children(n=32)with medulloblastoma(MB)who were treated using stratified therapy based on risk grading and also discussed the factors affecting prognosis.Methods:According to the risk stratification criteria,the cases were divided into the following four risk groups:low,standard,high,and very high.The 5-year overall survival(OS)and progression-free survival(PFS)rates were summarized.Further,the effects on the prognosis of tumor size,tumor stage,degree of resection,treatment mode,metastatic recurrence,molecular typing,and risk stratification were analyzed.Results:In the present study,following surgery,3 cases abandoned radiotherapy(RT)and chemotherapy(CHT),7 cases(<3 years of age)received only CHT,and 22 cases received combined RT and CHT.Total and near-total tumor resections were performed in 29 cases(90.6%).Subtotal resections were performed in 3 cases,and there were no surgery-related deaths.The average follow-up duration was 47 months.The average 5-year PFS and OS rates were 57.3%±7.2%and 68.7%±8.6%,respectively.The OS and PFS rates were significantly correlated with tumor-risk stratification,molecular staging,tumor stage,treatment mode,and recurrence after surgery(p<0.01).The degree of tumor resection,pathological type,and the presence of preoperative implantation were secondary factors affecting the prognosis(p<0.05).Age was correlated with the PFS rate.There was no correlation between age/tumor location/tumor size and prognosis(p>0.05).Favorable prognostic factors in the low-and standard-risk groups were stage M0,wingless-type MB,postoperative RT combined with CHT,no postoperative recurrence,age≥3 years,and total tumor resection.Conclusions:Personalized treatment strategies based on the risk stratification of MB and postoperative stratified comprehensive treatment could help improve the prognosis for MB.

Adaptive Metric Learning for Dimensionality Reduction

Finding a suitable space is one of the most critical problems for dimensionality reduction. Each space corresponds to a distance metric defined on the sample attributes, and thus finding a suitable space can be converted to develop an effective distance metric. Most existing dimensionality reduction methods use a fixed pre-specified distance metric. However, this easy treatment has some limitations in practice due to the fact the pre-specified metric is not going to warranty that the closest samples are the truly similar ones. In this paper, we present an adaptive metric learning method for dimensionality reduction, called AML. The adaptive metric learning model is developed by maximizing the difference of the distances between the data pairs in cannot-links and those in must-links. Different from many existing papers that use the traditional Euclidean distance, we use the more generalized l2,p-norm distance to reduce sensitivity to noise and outliers, which incorporates additional flexibility and adaptability due to the selection of appropriate p-values for different data sets. Moreover, considering traditional metric learning methods usually project samples into a linear subspace, which is overstrict. We extend the basic linear method to a more powerful nonlinear kernel case so that well capturing complex nonlinear relationship between data. To solve our objective, we have derived an efficient iterative algorithm. Extensive experiments for dimensionality reduction are provided to demonstrate the superiority of our method over state-of-the-art approaches.

Large eddy simulation of a planar jet flow with nanoparticle coagulation

Coagulation and growth of nanoparticles subject to large coherent structures in a planar jet has been explored by using large eddy simulation. The particle field is obtained by employing a moment method to approximate the nanoparticle general dynamic equa- tion. An incompressible fluid containing particles of 1 nm in diameter is projected into a particle-free ambient. The results show that the coherent structures dominate the evolution of the nanoparticle number intensity, diameter and polydispersity distributions as the jet develops. In addition, the coherent structures act to increase the diffusion of particles, and the vortex rolling-up makes the particles distributing more irregularly while the vortex pairing causes particle distributions to become uniform. As the jet travels downstream, the time-averaged particle number concentration becomes lower in the jet core and higher in the outskirts, whereas the time- averaged particle mass over the entire flow field maintains unaltered, and the time-averaged particle diameter and geometric standard deviations grow and reach their maximum on the interface of the jet region and the ambient.

Vertical root distribution and root cohesion of typical tree species on the Loess Plateau, China

Black locust（Robinia pseudoacacia L.） and Chinese pine（Pinus tabulaeformis Carr.） are two woody plants that are widely planted on the Loess Plateau for controlling soil erosion and land desertification. In this study, we conducted an excavation experiment in 2008 to investigate the overall vertical root distribution characteristics of black locust and Chinese pine. We also performed triaxial compression tests to evaluate the root cohesion（additional soil cohesion increased by roots） of black locust. Two types of root distribution, namely, vertical root（VR） and horizontal root（HR）, were used as samples and tested under four soil water content（SWC） conditions（12.7%, 15.0%, 18.0% and 20.0%, respectively）. Results showed that the root lengths of the two species were mainly concentrated in the root diameter of 5–20 mm. A comparison of root distribution between the two species indicated that the root length of black locust was significantly greater than that of Chinese pine in nearly all root diameters, although the black locust used in the comparison was 10 years younger than the Chinese pine. Root biomass was also significantly greater in black locust than in Chinese pine, particularly in the root diameters of 3–5 and 5–10 mm. These two species were both found to be deep-rooted. The triaxial compression tests showed that root cohesion was greater in the VR samples than in the HR samples. SWC was negatively related to both soil shear strength and root cohesion. These results could provide useful information on the architectural characteristics of woody root system and expand the knowledge on shallow slope stabilization and soil erosion control by plant roots on the Loess Plateau.

Anchorage properties at the interface between soil and roots with branches

Roots play an important role in stabilizing and strengthening soil. This article aims to study the mechanical properties of the interface between soil and roots with branches, using the pullout test method in the laboratory. The mechanical properties of the soil-root with branches interface is determined through the pullout-force and root-slippage curve （F-S curve）. The results of investigating 24 Pinus tabulaeformis single roots and 55 P. tabulaeformis roots with branches demonstrated three kinds of pullout test failures： breakage failure on branching root, breakage failure on branching node, and pullout failure. The branch angle had a remarkable effect on the failure mode of the roots with branches： the maximum pullout force increased with the sum of the branch diameters and the branch angle. The peak slippage and the initial force had a positive correlation with the sum of the branch diameter. The sig- nificance test of correlation between branch angle and the initial force, however, showed they had no correlation. Branch angle and branch root diameter affect the anchorage properties between root system and soil. Therefore, it is important to investigate the anchorage mechanics of the roots with branches to understand the mechanism of root reinforcement and anchorage.

An insight into failure mechanism of NASICON-structured Na3V2（PO4）3 in hybrid aqueous rechargeable battery

NASICON (Na-super-ionic-conductors)-structured materials have attracted extensive research interest due to their great application potential in secondary batteries. However, the mechanism of capacity fading for NASICON-structured electrode materials has been rarely studied. In this paper, we synthesized the NASICON-structured Na3V2(PO4)3/C composite by simple sol-gel and high-temperature solid-phase method and investigated its electrochemical performance in Na-Zn hybrid aqueous rechargeable batteries. After characterizing the structure, morphology and composition variations as well as the interfacial resistance changes of Na3V2(PO4)3/C cathode during cycling, we propose a mechanical and interfacial degradation mechanism for capacity fading of NASICON-structured Na3V2(PO4)3/C in Na-Zn hybrid aqueous rechargeable batteries. This work will shed light on enhancing the mechanical and in terfacial stability of NASICON-structured Na3V2(PO4)3/C in Na-Zn hybrid aqueous rechargeable batteries.

Bronze TiO2 as a cathode host for lithium-sulfur batteries

Lithium-sulfur batteries(LSBs)are very promising for large-scale electrochemical energy storage.However,dissolution and shuttling of lithium polysulfides(LiPSs)intermediates have severely affected their overall electrochemical properties and limited their practical application.Designing polar cathode hosts that can effectively bind LiPSs and simultaneously promote their redox conversion is crucial for realizing high-performance LSBs.Herein,we report bronze TiO2(TiO2-B)nanosheets(~5 nm in thickness)chemically bonded with carbon as a novel multifunctional cathode host for advanced LSBs.Experimental observation and first-principles density functional theory(DFT)calculations reveal that the TiO2-B with exposed(100)plane and Ti^3+ions exhibited high chemical affinity toward polysulfides and effectively confined them at surface.Meantime,Ti^3+ions and interface coupling with carbon promoted electronic conductivity of the composite cathode,leading to enhanced redox conversion kinetics of LiPSs during charge/discharge.Consequently,the as-assembled TiO2-B/S cathode manifested high capacity(1165 mAh/g at 0.2 C),excellent rate capability(244 mAh/g at 5 C)and outstanding cyclability(572 mAh/g over 500cycles at 0.2 C).This work sheds insights on rational design and fabrication of novel functional electrode materials for beyond Li-ion batteries.

Analysis on Main Traits of Spring Wheat Landraces in Tibet

In this study, 9 main traits of 774 spring wheat landraces in Tibet were investigated and analyzed. The results show that spring wheat landraces in Tibet have high plant height (with an average of 126.1 cm) and long growth period (with an average of 135.2 d), with an average spike length of 9.5 cm, average effective tiller number per plant of 5.9, average spikelet number per spike of 19.9, average kernel number per spikelet of 3.5, average spikelet number per spike of 51.8, average kernel weight per spike of 2.0 g, and average 1 000-grain weight of 38.1 g. Specifically, kernel number per spikelet of 2 landraces is larger than 6.0, spikelet number per spike of 2 landraces is larger than 100, kernel weight per spike of 2 landraces is larger than 4.0 g, 1 000-grain weight of 11 landraces is larger than 50 g. There is abundant genetic diversity in those traits except in growth period, and the coefficient variation of 9 traits is in a decreasing order of effective tiller number per plant > kernel weight per spike > kernel number per spike > spike length > kernel number per spikelet > 1 000-grain weight > plant height > spikelet number per spike > growth period. There is different relevance among different traits. Growth period is extremely significantly positively related to yield traits; grain number traits are extremely significantly positively relative to plant height and spike length, but extremely significantly negatively relative to effective tiller number per plant; kernel number per spike is extremely significantly positively relative to kernel weight per spike, but extremely significantly negatively related to 1 000-grain weight; 1 000-grain weight is extremely significantly positively related to kernel weight per spike. Based on principal component analysis, these 9 traits could be included by 5 principal components (grain number, grain weight, spike length, tiller number and growth period). According to the comprehensive evaluation values of these five principal components, 50 landraces including ZM019573, ZM019849, ZM019730, ZM018745, ZM019657, ZM019891, ZM020533, ZM018508, ZM019074 and ZM020026 have good performance.

Construction of Water-saving Ecological Aquaculture Model in Ponds in North China

[Objectives]To explore the ecological aquaculture model in ponds in North China,several single techniques were assembled into the same culture system.[Methods]Three ponds were selected,the species and stocking rate were exactly the same,the water was not changed during the culture period,and the water loss due to evaporation and leakage was recovered.Since the middle of May,the hydrochemical indicators such as ammonia nitrogen,nitrite nitrogen,water temperature,dissolved oxygen and pH were monitored every 10 d.According to the monitoring results of ammonia nitrogen,carbon sources were added to the culture ponds to adjust the ratio of C to N,and carbon sources were added 9 times during the culture period.The stocking rate and yield per unit area were accurately measured at the beginning and end of the experiment,and no less than 30 fishes were randomly sampled to calculate the relevant growth indicators and feed coefficients.[Results]Except that the nonionic ammonia in pond 3#exceeded the standard by 10.3%on July 25,all other hydrochemical indicators met the Fisheries Water Quality Standard,and there was no significant difference in all hydrochemical indicators at the same time(P>0.05).The survival rate in 3 ponds was more than 95.0%,the average body weight of individuals out of the pond had no difference(P>0.05),and the feed coefficient was 1.41-1.43.There was no disease during the culture period,and the water was saved by 46.6%compared with the traditional culture model.[Conclusions]This study can provide a basis for the construction of a new model suitable for ecological aquaculture in ponds in North China.

Erratum to"HLA-E-restricted Hantaan virus-specific CD8^(+)T cell responses enhance the control of infection in hemorrhagic fever with renal syndrome"[Biosaf.Health 5(2023)289-299]

The publisher regrets that during proofreading of the figure legend of Fig.6,the P value was misspelled in the sentence"while"n.s."indicates no significant difference P<0.05".It should be corrected to""while"n.s."indicates no significant difference(P>0.05)".

FRACTURE序列与CT评估膝关节和踝关节骨质改变的一致性研究

目的探讨MRI基于受限回波间距的快速梯度回波类CT成像(FRACTURE)序列与CT图像评估膝关节和踝关节骨质改变的一致性。方法回顾性收集2020年11月至2021年11月大连医科大学附属第一医院行CT及MRI FRACTURE序列检查的膝关节或踝关节患者, 共17例, 其中膝关节14例, 踝关节3例。依据关节组成骨数量共纳入80个组成骨, 其中股骨及髌骨各14个, 胫骨及腓骨各17个, 距骨、足舟骨、内侧楔骨、中间楔骨、外侧楔骨及跟骨各3个。由2名观察者分别通过CT及FRACTURE图像对关节组成骨的骨折、骨质增生、骨质破坏进行评估。采用Kappa检验分析观察者间采用CT和FRACTURE图像对关节组成骨病变评估的一致性。结果观察者1通过CT和FRACTURE图像对骨折、骨质增生、骨质破坏一致性评估的Kappa值(95%CI)分别为0.925(0.823~1.027)、0.905(0.799~1.011)和0.895(0.752~1.038), 观察者2分别为0.963(0.892~1.034)、0.933(0.843~1.023)、0.886(0.731~1.041)。观察者1和观察者2通过CT图像对骨折、骨质增生、骨质破坏评估的一致性Kappa值(95%CI)分别为1.000(1.000~1.000)、0.937(0.851~1.023)、0.945(0.839~1.051), 通过FRACTURE图像分别为0.962(0.888~1.036)、0.966(0.899~1.033)、0.836(0.656~1.016)。结论对于评价膝关节、踝关节组成骨的骨折、骨质增生、骨质破坏, MRI FRACTURE序列与CT图像具有高度的一致性。

再生循环水网络设计在火电厂的应用

为解决水网络集成优化方法在火电厂水网络优化应用中存在的问题,该研究对杂质的传递过程进行了扩展,使用移质推动描述杂质负荷单元用水过程,以及用最大移质能力及移除率描述再生过程,并通过邻接矩阵描述网络单元间的连接关系,从而构建再生循环水网络模型;对3300 MW火电厂进行模型应用研究,将案例水网络划分为9个用水子系统,等效拆分为11个用水单元并对移质单元构建浓度修正模型从而实现最大移质过程,选取Cl^(-)、总悬浮固体(SS)、SO_(4)^(2-)三个杂质指标进行节水优化应用,通过对该优化问题KKT条件进行求解从而实现模型的简化,优化后水网络新鲜水取用量减少6.7%、排污量减少62.9%。通过案例研究表明,构建的基于“供-用-耗-排”过程的再生循环水网络模型是成功的,可实现火电厂多杂质指标、复杂系统考虑再生循环的水网络节水优化设计,解决了水网络集成优化方法在火电厂应用中单元间回用过程描述不够准确以及再生单元描述不适用于节水改造情景的问题。

Impact of oxygen-containing carbonyl and ether groups on dielectric properties of poly(oxa)norbornene cyclic olefins

Flexible dielectric polymers that can withstand high electric field and simultaneously have high dielectric constant are desired for high-density energy storage.Here,we systematically investigated the impact of oxygen-containing ether and carbonyl groups in the backbone structure on dielectric properties of a series of cyclic olefin.In comparison to the influence of the-CF3 pendant groups that had more impact on the dielectric constant rather than the band gap,the change of the backbone structure affected both the dielectric constant and band gaps.The one polymer with ether and carbonyl groups in the backbone has the largest band gap and highest discharge efficiency,while it has the lowest dielectric constant.The polymer without any ether groups in the backbone has the smallest band gap and lowest discharge efficiency,but it has the highest dielectric constant.Polymers that have no dipolar relaxation exhibit an inversely correlated dielectric constant and band gap.Enhancing the dipolar relaxation through rational molecular structure design can be a novel way to break through the exclusive constraint of dielectric constant and band gap for high-density energy storage.

HLA-E-restricted Hantaan virus-specific CD8^(+)T cell responses enhance the control of infection in hemorrhagic fever with renal syndrome

Infection with the Hantaan virus(HTNV)may result in severe hemorrhagic fever with renal syndrome(HFRS).The functions of HLA-E-restricted CD8^(+)T lymphocytes in virus control and vaccine development have recently received increased attention.The purpose of this research is to discover HLA-E-restricted CD8^(+)T cell epitopes on HTNV as well as the features of these epitope-specific CD8^(+)T cells in HFRS patients.To anticipate HLA-Erestricted HTNV epitopes,the NetMHCpan servers were utilized.The K562/HLA-E cell binding test and the enzyme-linked immunospot assay were used to confirm epitope binding to HLA-E.The number and features of HLA-E-restricted epitope-specific CD8^(+)T lymphocytes in HFRS patients were investigated using tetramer staining,intracellular cytokine labeling,proliferation,and cytotoxicity assays.Six HTNV-derived HLA-Erestricted CD8^(+)T cell epitopes were found in this study.In mild/moderate HFRS patients,the frequency of HLA-E-restricted epitope-specific CD8^(+)T cells was greater than in severe/critical patients.CD38+HLA-DR+HLA-E-restricted CD8^(+)T cells were identified.Meanwhile,CD45RA^(+)CCR7^(-)effector memory-re-expressing CD45RA T cells with early and intermediate maturation and differentiation characteristics predominated.Notably,CD8^(+)T cells from milder HFRS patients produced more interferon-γ,interleukin-2,and granzyme B,had a stronger proliferative potential,and were inversely linked with the amount of plasma HTNV virus load.Furthermore,HLA-E-restricted epitope-specific CD8^(+)T cells demonstrated improved cytotoxic activity in vitro during the acute stage of HFRS.Taken together,the findings demonstrate the protective effects of HLA-E-restricted CD8^(+)T cells during HTNV infection,suggesting that HLA-E-targeted vaccines against HTNV might be developed for HLA-diverse populations.

Highly Selective Photocatalytic Conversion of Glucose on Holo-Symmetrically Spherical Three-Dimensionally Ordered Macroporous Heterojunction Photonic Crystal

Photocatalytic conversion of biomass is considered an effective,clean,and environmentally friendly route to obtain high-valued chemicals and hydrogen.However,the limited conversion efficiency and poor selectivity are still the main bottlenecks for photocatalytic biomass conversion.Herein,we report the highly selective photocatalytic conversion of glucose solution on holosymmetrically spherical three-dimensionally ordered macroporous TiO_(2)-CdSe heterojunction photonic crystal structure(s-TCS).The obtained s-TCS photocatalysts show excellent stability and strong light harvesting,uniform mass diffusion and exchange,and efficient photogenerated electrons/holes separation and utilization.The optimized s-TCS-4 photocatalyst displays the highest photocatalytic performance for glucose oxidation and hydrogen production.The glucose conversion,lactic acid selectivity,and yield on s-TCS-4 are about 95.9%,94.3%,and 96.4%,respectively.The photocatalytic production of lactic acid for s-TCS-4(18.5 g/L)is 2.3 times higher than the pure spherical TiO_(2) photonic crystal without CdSe(s-TiO_(2),8.1 g/L),and the hydrogen production rate of s-TCS-4 is 9.4 times that of s-TiO_(2).For the first time,we reveal that the photocatalytic conversion of glucose to lactic acid is a third-order and four-electron-involved reaction.This work could shed some new light on the efficient photocatalysis conversion of biomass to highly value-added products with high selectivity and yield,and simultaneously sustainable hydrogen evolution.

Slow Photon-Enhanced Heterojunction Accelerates Photocatalytic Hydrogen Evolution Reaction to Unprecedented Rates

In photocatalysis,both the photogenerated charge separation and transport and the induced light utilization greatly influence performance.In this work,highly ordered CdS@ZnO core-shell inverse opal(CdS@ZnO-csIO)nanocomposites have been successfully designed as a model to couple the heterojunction system with the slow photon effect for photocatalytic H2 production.Theoretical calculations and experimentation provide direct evidence for the slow photon effect in the CdS@ZnO-csIO nanocomposites.The type II heterojunction is responsible for promoting the migration and separation of photogenerated charges,and the slow photon effect is in charge of enhancing light harvesting in the CdS@ZnO-csIO nanocomposites.This synergy of two functions gives rise to a significantly enhanced photocatalytic H2 production rate under simulated solar light for the CdS@ZnO-csIO nanocomposites.The highest H2 production rate reaches 48.7 mmol g^(−1)h^(−1)under simulated solar light with the benchmark performance for all reported CdS@ZnO composites.Our work provides proof-of-principle that coupling the heterojunction system with the slow photon effect can greatly enhance the photocatalytic activity of composite photocatalysts.

Heterogenous glucose-stimulated insulin secretion at single islet level

Insulin secretion by pancreatic islets plays a vital role in regulating blood glucose levels.Nevertheless,the mech-anism responsible for this dynamic insulin secretion has not been completely understood,particularly at the single islet level.In this study,we have successfully developed an easy microfluidic platform that allows for the exploration of dynamic glucose-stimulated insulin secretion(GSIS)at the single islet level.With the utilization of this platform,we evaluated dynamic GSIS from single islets isolated from both normal and diabetic rats.Our results demonstrate that islets can be categorized into three types based on their dynamic GSIS:Type Ⅰ exhibits a biphasic GSIS profile with a fast first phase and flat second phase;Type Ⅱ also has a biphasic GSIS profile with a fast first phase but a slow increased second phase;Type Ⅲ displays only a slowly increased second phase and lacks a fast first phase.RNA sequencing analysis demonstrated that the cell type and exocytosis-specific genes are consistent with the proportion of cells and insulin release kinetics among the three types of islets,respectively.Moreover,our findings suggest that high expression of Atp5pb is anti-correlated with the first phase of insulin secretion.Furthermore,we revealed that diabetic islets exhibit only the type Ⅰ GSIS response,indicating a deliberate impairment of the second phase of insulin secretion.Together,this device serves as a crucial tool in the research field of islets and diabetes,allowing researchers to investigate islet functional heterogeneity and identity at the single islet level.

金融衍生品、税收征管强度与企业所得税负担

本文使用A股上市公司2008—2015年的数据,实证分析了金融衍生品对企业所得税负担的影响。研究发现,金融衍生品具备交易结构复杂、参与主体多元化以及不确定性等特征,导致其在投资决策、价值计量、会计确认等环节的交易实质难以理解辨认,因此金融衍生品可以用于降低企业所得税负担。此外,结合我国金融市场的发展背景和现存针对金融衍生品的税制发展情况,本文发现在税法制度发展滞后、法律体系建设不完善、税务机关监管困难的背景下,税收征管未能较好地发挥抑制企业从事税务筹划活动的外部治理作用。

Mechanistic studies of the transport of peimine in the Caco-2 cell model

Fritillaria thunbergii Miq. has been widely used in traditional Chinese medicine for its expectorant, antitussive, antiinflammatory and analgesic properties. Moreover, modern pharmacological studies have demonstrated that F. thunbergii Miq. has efficacy in the treatment of leukemia and cancers of the liver and cervix. Although the alkaloid, peimine, is largely responsible for these pharmacological effects, it has very low oral bioavailability. The aim of this study was to investigate the intestinal absorption of peimine in Caco-2 cell monolayers. Having demonstrated that peimine is non-toxic to Caco-2 cells at concentrations o200 μmol/L, the effect of peimine concentration, p H, temperature, efflux transport protein inhibitors and EDTA-Na_2 on peimine transport were studied. The results show that peimine transport is concentration-dependent; that at p H 6.0 and 7.4, the P_(app(AP-BL))of peimine is not significantly different but the Papp(BL-AP)) is; that both Papp(AP-BL)and P_(app(BL-AP))at 4 1C are significantly higher than their corresponding values at 37 1C; that the P-glycoprotein(P-gp) inhibitors, verapamil and cyclosporin A, increase absorption of peimine; and that EDTA-Na2 has no discernible effect. In summary,the results demonstrate that the intestinal absorption of peimine across Caco-2 cell monolayers involves active transport and that peimine is a substrate of P-gp.