Two New Xanthone Glycosides from Polygala tenuifolia

Two new xanthone glycosides, polygalaxanthone IV and V were isolated from the roots of Polygala tenuifolia Willd. Their structures were established as 6-O-[a-L-rhamnopyranosyl- (12)-b-D-glucopyranosyl]-1-hydroxy-3, 7-dimethoxyxanthone (polygalaxanthone IV), and 6-O- [a-L-rhamnopyranosyl-(12)-b-D-glucopyranosyl]-1, 3-dihydroxy-7-methoxyxanthone (polyga- laxanthone V), respectively, on the basis of chemical and spectral evidence.

A new glycoside from Polygala tenuifolia Willd

A new tdterpenoid glycoside, 3-β-O-β-D-glucopyranosyl presenegenin 28-O-α-L-arabipyranosyl（1 → 3）-6-β- xylopyranosyl（1 → 4）-[β-D-apiofuranosyl（1 → 3）]-Ct-L-rhamnopyranosyl（1 → 2）-[α-L-rhamnopyranosyl（1 → 3）]-β-D-fucopyranosyl ester （1） was isolated from the Polygala tenuifolia Willd., together with two known saponins, including polygalasaponinXXIV （2） and polygalasaponinXXVIII （3）. The structure of new compound was elucidated by spectroscopic methods.

Analysis on the Medication Law of Drug Pair Acorus Tatarinowii-Polygala Tenuifolia Based on the Dictionary of Traditional Chinese Medicine Prescriptions

Objective:Using data mining method to dig and sort out the prescriptions with Acorus tatarinowiiPolygala tenuifolia drug pair,and summarize the medication characteristics and compatibility of their prescriptions after preliminary screening.Methods:By searching the Dictionary of Traditional Chinese Medicine Prescriptions,a standardized database of prescriptions was established,and the properties,tastes and meridian tropism of prescriptions were classified,and the indications of prescriptions and core combinations of traditional Chinese medicines were analyzed.Results:178 prescriptions were collected,of which 210 were related.Most of the drugs were warm in nature and sweet in taste,and mainly return to the heart and kidney meridians.Under the same confidence and different support,the core drug combination for treating brain diseases was Acorus tatarinowiiPolygala tenuifolia-Ginseng,and the core drug combination for treating asthenia was Acorus tatarinowii-Poria cocos-Rehmannia glutinosa-Polygala tenuifolia.Conclusion:The compatibility characteristics of the prescriptions containing Acorus Tatarinowii and Polygala tenuifolia in the Dictionary of Traditional Chinese Medicine Prescriptions are remarkable,which provides reference for scientific guidance of clinical rational drug use and basic research of prescriptions containing Acorus tatarinowii and Polygala tenuifolia.

Network mechanism on effective constituents from Polygala Tenuifolia for anti-Alzheimer Disease

OBJECTIVE To clarify out the network pharmacology mechanism of Polygala tenuifolia against Alzheimer disease(AD).METHODS Firstly,we collected the chemical constituents from Polygala tenuifolia and key targets toward AD.Machine learning algorithms were applied to construct classifi.ers for predicting the effective constituents.Secondly,docking models were utilized for further evalua.tion.Finally,we built constituent-target,target-target network and target-biology pathway network.RE.SULTS 104 chemical constituents Polygala tenuifolia from were collected.Through prediction of bloodbrain penetration and validation,36 chemical constituents were selected among 100 chemical constitu.ents,their action targets mainly focused on AChE,COX-2,TNF-α,insulin-degrading enzyme and APP.Their main structure types include Polygala saponins,Polygala glycosides,Polygala shrubby ketones,polygala xanthones and sterols,which acted on AchE,APP,M-TAU,GSK3β and 5 HT1A with high fre.quency.Gene-Ontology and KEGG enrichment analysis showed that the main pathways of these con.stituents involve in neurotransmitter release,synaptic conduction and synaptic plasticity,apoptosis reg.ulation,phosphorylation pathway,Ca^(2+) signaling pathway,and so on.CONCLUSION This study uncov.ered a network mechanism of Polygala tenuifolia against Alzheimer disease,which may provide impor.tant information for the further study and new drug development.

Effects of Different Storage Conditions on Physiological and Biochemical Characteristics of Polygala tenuifolia Willd. Seeds

[Objectives] Taking Polygala tenuifolia Willd. seeds as experimental material, the changes of physiological and biochemical characteristics of seeds under different storage temperatures and seed moisture contents were studied. [Methods] The seeds of P. tenuifolia Willd. with moisture contents of 3%, 5% and 15% were stored at-10 ℃, 0 ℃, 20 ℃ and 36 ℃, respectively, and the storage time was one year. The physiological and biochemical characteristics of the seeds, such as conductivity, SOD activity, POD activity, and soluble sugar content were studied.[Results] After one-year storage, as the storage temperature and seed moisture content increased, the relative conductivity, MDA content and soluble sugar content of P. tenuifolia Willd. seeds increased, while the SOD activity, POD activity, and protein content declined. This phenomenon was most obvious in the P. tenuifolia Willd. seeds with moisture content of 15%. [Conclusions] This study will provide reference for seed storage of medicinal plants.

Localization and Dynamic Change of Saponin in Vegetative Organs of Polygala tenuifolia

Anatomical, histochemical and phytochemical methods were used to investigate the structure, localization and dynamic changes of total saponin and senegenin of vegetative organs in Polygala tenuifolia Willd. Histochemical localization results showed that saponin accumulated mainly in parenchyma cells of vegetative organs. The phytochemical results also showed that the saponin accumulated in the vegetative organs of P. tenuifolia, with higher content in roots and lower content in the aerial parts that included stems and leaves. The saponin content and dry weight of the vegetative organs of P. tenuifolia had dynamic variance at the developmental stages and all reached the highest level in the post-fruit period. Hence, the roots and aerial parts should be gathered in August to make full use of the plant. As the root is the main medicinal organ of P. tenuifolia, the content of total saponin and senegenin of different aged and different parts of the root were determined. The content of total saponin and senegenin exhibited a sustained decreasing trend with increasing root age; therefore, the annual roots had high quality. The content of total saponin and senegenin in different parts of the root showed obvious variation. The content in the ＂skin areas＂ was much higher than that of xylem. The results offer a theoretical basis for determining the appropriate harvesting stage and a reasonable harvest of P. tenuifolia.

Sedative and Hypnotic Effects and Transcriptome Analysis of Polygala tenuifolia in Aged Insomnia Rats

Objective:To study the sedative and hypnotic effects and underlying mechanisms of Polygala tenuifolia(PT)on treating aged insomnia rats.Methods:Sixty Sprague-Dawley male rats were divided into 6 groups by a random number table,including control group,model group,diazepam group(0.92 mg/kg),as well as PT low-,medium-and high-dose groups(0.0875,0.175,0.35 g/kg,respectively),10 rats in each group.Aged insomnia rat model was established with subcutaneous injection of D-galactose for 42 days and then intraperitoneal injection of para-chlorophenylalanine for 3 days.PT and diazepam were respectively given to aged insomnia rats by intragastric administration for 7 days after model establishment.Then the rats were investigated by body weight,Morris water maze test,pentobarbital test,enzyme-linked immunosorbent assay,and transcriptome sequencing.Results:Compared with the model group,PT increased the body weight,improved memory ability,and prolonged pentobarbital-induced sleep time of aged insomnia rats(P<0.01 or P<0.05).The medium dose of PT also increased the neurotransmitter levels of 5-hydroxytryptamine(5-HT)and gamma-aminobutyric acid(GABA),and decreased the level of Glu in the hippocampus of aged insomnia rats(P<0.05 or P<0.01).Twenty-four differentially expressed genes(DEGs)were overlapped among model group,medium-dose PT group,and diazepam group in transcriptome analysis.Fuom and Pcp2 were down-regulated by the treatment of medium-dose PT(P<0.01 or P<0.05).The metabolic pathways of PT were relatively less than diazepam(91 vs.104).Conclusions:The sedative and hypnotic effects of PT in aged insomnia rats might be related to neuro,metabolism pathways,especially through GABAergic signaling pathway.It provided more effective herb choice for the treatment of senile insomnia.

Effects of the crude extract of Polygala tenuifolia Willd on human sperm in vitro

The aim of the present study is to analyze sperm membrane changes and the spermicidal effect in treatment with the crude extract from Polygala tenuifolia Willd (PTW) in vitro.The root of PTW was extracted in distilled water.Normal human spermatozoa were used to assess the spermicidal activity (Sander-Cramer assay) of the extract from the PTW root.The hypo-osmotic swelling (HOS) test and the eosin Y (EY) staining were used to detect the integrity of sperm membrane and vitality.The sperm chromatin dispersion (SCD) test was performed to determine sperm DNA integrity.N-9 was used as a reference standard and semen added to physiological saline was used as the control.Semen samples were donated by 42 healthy fertile men.The crude extract from the root of PTW could immobilize and kill 100% spermatozoa within 20 s in vitro at the concentrations of 20.0 and 10.0 mg/ml;at the concentration of 5.0 mg/ml,spermatozoa were immobilized in (39.5±3.2) s.In the groups of the crude extract from the root of PTW and N-9 solution,the rate of the normal HOS (tails swollen) and the white head (unstained) was 0%,and the rate of the abnormal HOS (tails unswollen) and red head (stained) was 100%.Sperm DNA fragmentation showed no change in exposure to the crude extract from the root of PTW and N-9 solution.The sperm revival test did not show any spermatozoa that recovered their motilities.The rapid spermicidal activity of the crude extract from the root of PTW in vitro may occur by the disruption of the sperm membrane integrity.

对药“远志-酸枣仁”中CaMKⅡ调控成分的虚拟筛选及抗癫痫活性的研究

目的对“远志-酸枣仁”中潜在作用于钙/钙调蛋白依赖性蛋白激酶Ⅱ(calcium/calmodulin-dependent protein kinaseⅡ,CaMKⅡ)靶点的活性物质进行筛选,阐明其药效物质基础。方法采用以药效团为基础的虚拟筛选手段,通过收集已出版文献中报道的具有调控CaMKⅡ作用的化合物信息,建立基于CaMKⅡ配体的HipHop药效团模型,收集文献中报道的“远志-酸枣仁”中的成分并建立化合物库,对“远志-酸枣仁”中的成分与药效团进行匹配,随后使用分子模拟对接手段对匹配到的小分子化合物与CaMKⅡ靶点(PDB ID:2V7O)进行对接,研究潜在活性单体与CaMKⅡ的作用。用戊四唑(pentylenetetrazol,PTZ)点燃模型对活性单体细叶远志苷A(39)的抗癫痫作用进行测定,并对CaMKⅡ水平的调控作用进行评价。结论通过文献检索建立包含“远志-酸枣仁”中109种化学成分的化合物库,通过测试集验证确定将药效团03用于对“远志-酸枣仁”化合物库的虚拟筛选,对匹配度排前6位的单体通过分子模拟对接分析其与CaMKⅡ的作用情况,并用抗癫痫动物模型对单体的活性进行评价,化合物39能够在中高剂量下延长PTZ致癫痫发作的潜伏时间,改善PTZ所致的焦虑抑郁样行为,改善PTZ诱导的癫痫发作后脑内尼氏体丢失,提升PTZ所致的CaMKⅡ表达水平降低,提升海马CA1、CA3区及颞叶皮层内CaMKⅡ免疫阳性细胞数量并进一步对nAChR4受体水平进行调控。表明基于虚拟筛选与活性评价手段探讨“远志-酸枣仁”中CaMKⅡ调控作用的成分具有一定的准确性。

远志在神经系统退行性疾病中的研究进展

中药远志具有改善记忆、保护神经、抗痴呆等功效,不仅是古代名医治疗痴呆病症的高频药物,也常用于阿尔茨海默病、帕金森病、肌萎缩性侧索硬化症、颅脑损伤、癫痫、脑缺血等神经系统退行性疾病的临床治疗和研究。远志可通过减少异常蛋白沉积、降低炎症因子释放、减轻氧化应激损伤、调控神经递质等机制发挥保护神经元、改善认知障碍及其他症状的作用。因此,全面了解远志在神经系统退行性疾病中的作用机制,可以为疾病的治疗及药物研发提供新思路。

HPLC法测定远志中黄曲霉毒素B1含量的不确定度评定

为评定高效液相色谱法测定远志中黄曲霉毒素B1含量的不确定度,依据国家计量技术规范JJF 1059.1—2012《测量不确定度评定与表示》,对随机选取的6个远志样品,建立数学模型,从标准溶液稀释、样品称量、样品最终定容体积和仪器测定重复性等方面分析不确定度来源,量化不确定度分量,计算合成不确定度和扩展不确定度.实验结果表明远志中黄曲霉毒素B1测定结果合成标准不确定度为0.01639μg/kg,扩展不确定度0.03278μg/kg.不确定度评定结果表明:HPLC法对远志中黄曲霉毒素B1含量的测定数据可靠,远志中黄曲霉毒素B1含量的测量不确定度主要来源于重复性实验、标准曲线的拟合、液相色谱仪的使用.

HPLC-PDA波长切换法测定远志-石菖蒲药对中4种主要成分的含量

目的 建立高效液相色谱-二极管阵列检测器(HPLC-PDA)波长切换法同时测定远志-石菖蒲药对提取液中4种主要成分远志 酮Ⅲ、3,6’-二芥子酰基蔗糖、β-细辛醚及α-细辛醚的含量。方法 采用Agilent TC-C18(250 mm×4.6 mm,5μm)色谱柱,流动相为甲醇-0.2%甲酸水溶液,梯度洗脱,检测波长分别为257 nm、320 nm,流速为0.8 mL·min^(-1),柱温30℃。结果 远志 酮Ⅲ、3,6’-二芥子酰基蔗糖、β-细辛醚及α-细辛醚在各自质量浓度范围与峰面积线性关系良好(r均≥0.9998),精密度、重复性、稳定性RSD值均小于5.0%;低、中、高浓度的平均加样回收率在100.79%~103.57%;远志-石菖蒲药对中远志 酮Ⅲ、3,6’-二芥子酰基蔗糖、β-细辛醚及α-细辛醚含量平均值分别为0.5829、3.7005、6.3593、1.4827 mg·g^(-1)。结论所建立的多成分含量测定方法简单、准确、重复性好,可用于远志-石菖蒲对药的质量控制。

基于动物实验和网络药理学技术探究五味子-远志治疗失眠的作用机制

目的:利用网络药理学技术结合小鼠睡眠实验,探讨五味子-远志配伍增效的科学内涵。方法:将KM小鼠随机分为空白对照组、艾司唑仑组、五味子∶远志各比例组、五味子和远志单味药组,灌胃10 d,末次灌胃后进行戊巴比妥钠诱导的睡眠实验,测定小鼠睡眠率和睡眠时间。搜集五味子和远志的成分及作用靶点;在Drugbank和DisGeNet数据库,以“失眠”为关键词检索疾病靶点,于Venny 2.1.0分别读取五味子-失眠、远志-失眠的交集作为五味子-远志治疗失眠的靶点,并导入String进行PPI分析,使用Cytoscape 3.9.0对结果进行拓扑分析,筛选核心靶点,并导入DAVID进行GO和KEGG分析。结果:五味子、远志单味药组及其各比例组较空白对照组均明显延长小鼠戊巴比妥钠诱导下的睡眠时间和睡眠率(P<0.05,P<0.01),且各比例组较五味子和远志单味药组均有更长的睡眠时间和睡眠率,其中五味子∶远志3∶1和2∶1组作用更显著(P<0.05,P<0.01)。GO和KEGG分析显示五味子-远志治疗失眠的作用机制可能与GABA能突触、5-羟色胺能突触、γ-氨基丁酸信号通路、多巴胺能突触等信号通路相关。结论:五味子-远志配伍增效治疗失眠可能与调节GABA、5-HT、5-HIAA、Glu等因子水平有关。

建昌帮炆法对远志4种成分在大鼠体内药代动力学和组织分布的影响研究

目的研究建昌帮炆法对远志中4种寡糖酯类成分在大鼠体内药代动力学和组织分布作用的影响。方法以炆远志为研究对象,生远志为对照,运用UPLC-MS/MS法测定远志炮制前后大鼠血浆和组织中西伯利亚远志糖A5、西伯利亚远志糖A6、细叶远志苷A、3,6'-二芥子酰基蔗糖的浓度。选取灌胃给药后13个时间点的血浆样品和4个时间点的组织样品,测定大鼠血浆和组织中4种寡糖酯类成分的浓度,并运用DAS 3.2.1软件计算药代动力学参数,SPSS 21.0分析主要参数的差异,比较两组血药浓度和组织浓度的差异。结果与生远志组相比,炆远志组西伯利亚远志糖A5、西伯利亚远志糖A6、3,6'-二芥子酰基蔗糖的Cmax和AUC0~12均明显增加(P<0.05),细叶远志苷A的Cmax和AUC0~12虽差异无统计学意义,但具有增加趋势,并在6个组织中浓度整体均增加。结论远志经炆制后,有利于4种寡糖酯类成分的吸收和分布,可提高其生物利用率。

基于高效液相色谱法测定不同产地、不同抽芯程度远志药材中4种成分的含量

目的 建立HPLC法测定不同产地、不同抽芯程度远志药材的主要成分,并比较其含量差异。方法 采用HPLC法对远志药材中西伯利亚远志糖A_(5)、西伯利亚远志糖A_(6)、远志酮、3,6’-二芥子酰基蔗糖4种化学成分的含量进行测定,采用聚类分析法比较其含量差异。结果远志4种成分在320 nm下分离度良好,西伯利亚远志糖A_(5)、西伯利亚远志糖A_(6)、远志酮、3,6’-二芥子酰基蔗糖低、中、高浓度的平均回收率在94.8%~106.8%。成分含量分析结果表明,不同产地的远志药材在不同抽芯程度下4种成分含量差异具统计学意义(P<0.05)。结论 该方法科学、简便、准确,可用于不同产地、不同抽芯程度远志药材成分含量测定。

对药远志-天麻中GABA-AT靶点抑制活性物质的虚拟筛选

目的 对对药远志-天麻中潜在作用于GABA转氨酶(GABA aminotransferase, GABA-AT)靶点的抗癫痫活性物质进行研究,阐明其药效物质基础。方法 收集文献中具有抑制GABA-AT活性的化合物信息,建立基于GABA-AT配体的HipHop药效团模型,收集文献中远志与天麻中的成分并建立化合物库,对远志与天麻中的成分与药效团进行匹配,采用柔性对接手段对匹配到的小分子化合物与GABA-AT靶点(PDB ID:1OHW)进行对接并评估其相互作用,采用体外酶活力法初步评价筛选到单体的GABA-AT的抑制活性。结果 通过文献检索共得到远志与天麻中化学成分26种,通过测试集验证选出优选药效团3用于对远志与天麻化合物库的虚拟筛选,匹配后得到10种远志与天麻中潜在的GABA-AT抑制成分。通过分子模拟对接分析了10种化合物对GABA-AT的作用情况,对其中4种单体进行了酶活力抑制能力评估。结论 基于药效团及分子模拟对接手段探讨远志与天麻中GABA-AT抑制成分具有一定的准确性。

远志中远志酮Ⅲ和3,6′-二芥子酰基蔗糖含量测定方法的改进

目的:改进《中国药典》2020年版所载远志中远志(口山)酮Ⅲ和3,6′-二芥子酰基蔗糖的含量测定方法,解决远志(口山)酮Ⅲ中包含杂质成分且无法完全分离及甲醇和70%甲醇对远志(口山)酮Ⅲ和3,6′-二芥子酰基蔗糖响应值差异大的问题。方法:对照品溶液和供试品溶液的制备均以甲醇作为溶剂,供试品溶液采用超声提取,采用UHPLC方法,以乙腈(A)-0.1%磷酸溶液(B)为流动相,梯度洗脱(0~5 min,10%A→14%A;5~12 min,14%A→17%A;12~17 min,17%A→19%A;17~22 min,19%A→21%A;22~30 min,100%A);柱温30℃,体积流量0.3 mL·min^(-1),检测波长320 nm,进样量3μL。结果:采用70%甲醇制备的远志(口山)酮Ⅲ和3,6′-二芥子酰基蔗糖对照品溶液的峰面积分别比采用甲醇制备的相同浓度对照品溶液的峰面积高38.9%和34.5%;采用药典方法测得的远志(口山)酮Ⅲ中实际包含了杂质成分远志(口山)酮Ⅺ,而采用UHPLC梯度洗脱方法可以将远志(口山)酮Ⅲ中包含的杂质成分远志(口山)酮Ⅺ完全分开。结论:改进方法解决了远志(口山)酮Ⅲ中包含杂质成分远志(口山)酮XI且无法完全分离及甲醇和70%甲醇对远志(口山)酮Ⅲ和3,6′-二芥子酰基蔗糖响应值差异大的问题,可以更准确地反映远志中这2个指标成分的真实含量。

基于网络药理学和指纹图谱的远志抗抑郁质量标志物的预测

目的预测远志药材抗抑郁的质量标志物(Q-marker),并建立其质量评价方法。方法利用网络药理学和分子对接,预测远志抗抑郁的核心成分。结合指纹图谱、化学模式识别方法对远志药材进行定性研究,寻找不同产地远志药材的共性成分,进一步确定远志药材中潜在的Q-marker。结果通过网络药理学分析,预测细叶远志皂苷、3,6'-二芥子酰基蔗糖、瓜子金皂苷ⅩⅩⅠ、远志酮Ⅲ、西伯利亚远志糖A5和西伯利亚远志糖A6等12个成分为远志抗抑郁的核心成分,通过作用于IL2、VEGFA、APP、HSP90AA1、PLCG1等关键靶点,从而调控信号通路,发挥抗抑郁作用。分子对接验证显示关键靶点与核心成分具有较好的结合活性。同时建立20批远志药材的指纹图谱,发现29个共有峰,相似度在0.95以上。综合网络药理学活性和成分的可测性以及Q-marker理念,最终确定3,6'-二芥子酰基蔗糖、远志酮Ⅲ、西伯利亚远志糖A5和西伯利亚远志糖A6为远志药材的Q-marker。结论本研究利用网络药理学进行初步预测,同时建立指纹图谱结合化学模式识别分析加以确定,为远志药材Q-marker的研究提供参考。

佤药远志醇提物对斑马鱼的助眠作用

该研究以佤药远志(娘母良)为试材,研究其改善睡眠的功效。采用高效液相色谱法(HPLC)检测佤药远志醇提物的主要活性成分及含量,以斑马鱼为实验动物,建立戊四唑(PTZ)斑马鱼失眠模型。实验设置正常对照组、模型组和处理组,处理组设置5个质量浓度,分别为125、250、500、1000、2000μg/mL,28℃处理1 d后,观察统计各组斑马鱼死亡数量和死亡率,测定远志醇提物对正常斑马鱼的最大耐受浓度(Maximum Talerated Concentration,MTC);根据MTC给予PTZ模型斑马鱼不同质量浓度的远志醇提物,设置阳性对照组(褪黑素组)和正常对照组,通过行为分析仪检测斑马鱼的觉醒活动时间和觉醒活动量。结果表明,MTC为1000μg/mL;观察时间内,阳性褪黑素组改善睡眠作用为29.00%,远志醇提物4个质量浓度处理组(125、250、500、1000μg/mL)改善睡眠作用依次为6.97%、22.78%、33.14%、47.26%,其中质量浓度为500μg/mL和1000μg/mL的远志醇提物改善睡眠作用明显优于阳性褪黑素组。以上结果显示远志醇提物对PTZ诱导的斑马鱼失眠症状具有一定的改善作用,但是在一定浓度范围内,呈剂量依赖性,浓度越高,作用越明显。

远志地上部分正丁醇部位化学成分研究

目的:研究远志Polygala tenuifolia Wild.地上部分的化学成分。方法:远志地上部分70%乙醇提取物的正丁醇萃取部位采用硅胶、中压十八烷基键合硅胶(ODS)色谱柱和高效液相色谱法(HPLC)进行分离纯化,根据理化性质和核磁共振波谱数据鉴定化合物的结构。结果:从远志地上部分70%乙醇提取物的正丁醇萃取部位中分离得到13个化合物,分别为顺式丁香苷(1)、长春花苷Ⅱ(2)、2-苯乙醇-β-D-葡萄糖苷(3)、吐叶醇(4)、4-C-[β-D-呋喃芹菜糖基-(1→6)-β-D-吡喃葡萄糖基]-1,3,6-三羟基-7-甲氧基氧杂蒽酮苷(5)、蚱蜢酮(6)、3-羟基-1-(4-羟基-3-甲氧基苯基)丙烷-1-酮(7)、polygalatenoside A(8)、刺槐林素(9)、3′,5′-二甲氧基双苯基-4-醇(10)、拟茎点霉内酯A(11)、莽吉柿酮D(12)和玫红穗状霉胺A(13)。结论:化合物2、4、6、7、9~13均为首次从远志科植物中分离得到。