鼓槌石斛化学成分的研究

自中药鼓槌石斛(Dendrobium chrysotoxum Lindl.)茎中分离到5个化合物,经光谱(UV,IR,MS,¹HNMR,DIFNOE和¹³CNMR)分析,分别鉴定为β-谷甾醇(I)、鼓槌菲(chrysotoxene,II)、毛兰素(erianin,III)、毛兰菲(confusarin,IV)和鼓槌联苄(chrysotobibenzyl,V)。II是新化合物,V是新天然产物。     

鼓槌石斛体外抗血小板聚集活性研究

目的 对鼓槌石斛提取物进行抗血小板聚集活性的药效筛选,并初步探讨其抗血栓作用。方法 将15只大鼠按体质量随机分为鼓槌石斛提取物1（gc1）组、鼓槌石斛提取物2（gc2）组、鼓槌石斛提取物3（gc3）组、鼓槌石斛提取物4（gc4）组及阳性对照（阿司匹林）组,每组3只;将15只豚鼠按体质量同法随机分为5组,每组3只。大鼠组和豚鼠组分别采用二磷酸腺苷（adenosine diphosphate,ADP）和花生四烯酸（arachidonic acid,AA）诱导体外血小板聚集实验,分别检测空白对照管与不同浓度的鼓槌石斛提取物及阿司匹林给药管的富血小板血浆在5 min内的最大聚集率,并计算血小板聚集的抑制率和各受试物的半数抑制浓度（IC₅₀）。结果 与空白对照组相比,gc1（5.318 mmol·L^-1）、gc2（1.708 mmol·L^-1）、gc3（2.925 mmol·L^-1）、gc4（3.152,1.576,0.394 mmol·L^-1）对ADP诱导的血小板最大聚集率显著降低（P<0.05或P<0.01）。与空白组相比,gc1（0.083,0.166 mmol·L^-1）、gc2（0.106,0.214 mmol·L^-1）、gc3（0.023 mmol·L^-1）、gc4（0.049,0.099,0.197,0.394 mmol·L^-1）对AA诱导的血小板最大聚集率显著降低（P<0.05或P<0.01）。结论 鼓槌石斛多种成分具有抗血小板聚集作用,在血栓性疾病中具有一定的积极作用。     

基于网络药理学和分子对接的鼓槌石斛素治疗宫颈癌作用机制探讨及实验验证

目的 采用网络药理学和分子对接方法,探究鼓槌石斛素治疗宫颈癌的作用机制并进行体外实验验证。方法 通过中药系统药理学数据库与分析平台(TCMSP)、PharmMaper和SwissTarget Prediction平台获得鼓槌石斛素的预测靶点;在GeneCards、TTD、OMIM、Disgenet、Drugbank疾病数据库筛选宫颈癌的潜在靶点;使用R软件Venn包获取鼓槌石斛素与宫颈癌的交集靶点基因,利用STRING网站与Cytoscape软件获取蛋白质-蛋白质相互作用(PPI)网络,筛得核心靶点,进行基因本体(GO)和京都基因与基因组百科全书(KEGG)富集分析;运用Autodock Vina 1.1.2软件和Pymol软件进行鼓槌石斛素和核心靶点之间的分子对接和可视化分析。体外培养宫颈癌SiHa细胞,用0、50、100 μmol·L^-1鼓槌石斛素处理细胞,采用MTT法、Transwell实验分别检测鼓槌石斛素对细胞增殖、迁移和侵袭的影响,Western blotting检测鼓槌石斛素对PI3K/Akt/mTOR信号通路中p-PI3K、PI3K、p-Akt、Akt、mTOR关键蛋白的调控作用。结果 共得到79个鼓槌石斛素调控宫颈癌的潜在交集靶点,按照网络拓扑分析中的度(degree)值筛选出HSP90AA1、ESR1、PIK3CA、mTOR、MAPK1、ABL1、PARP1等多个核心靶点;KEGG富集筛选出PI3K/Akt、Focal adhesion、细胞衰老、催乳素等30条信号通路;分子对接结果显示,其中靶蛋白HSP90AA1、ESR1、PIK3CA、mTOR、MAPK1与鼓槌石斛素结合能绝对值较高,说明可能是鼓槌石斛素治疗宫颈癌的作用位点。细胞实验验证表明,鼓槌石斛素处理SiHa细胞后,SiHa细胞增殖明显减少(P<0.01),且与鼓槌石斛素的浓度呈现负相关,同时SiHa细胞的迁移和侵袭能力下降。鼓槌石斛素处理SiHa细胞后,细胞中p-PI3K、Akt、p-Akt表达及p-PI3K/PI3K和p-Akt/Akt下调(P<0.05)。结论 鼓槌石斛素可通过多靶点、多通路发挥治疗宫颈癌的作用,鼓槌石斛素可能通过抑制PI3K/Akt/mTOR信号通路的表达来影响宫颈癌细胞的增殖、迁移和侵袭。     

鼓槌石斛中一新芴酮类化合物

自兰科植物鼓槌石斛Dendrobium chrysotoxum茎中分得一新的芴酮类化合物及三个已知化合物。该新化合物命名为鼓槌酮，结构为2，5，8－三羟基－1，4－二甲氧基－9－芴酮。     

4种药用石斛对增强小鼠免疫功能效果的比较研究

目的 比较铁皮石斛、金钗石斛、鼓槌石斛和流苏石斛4种药用石斛对增强小鼠免疫功能的效果。方法 4种石斛以0.25,0.50 g·kg^-1连续给予正常小鼠30 d后,测定小鼠的T淋巴细胞增殖能力、巨噬细胞吞噬率和吞噬指数;4种石斛以0.25,0.50 g·kg^-1连续给予受环磷酰胺免疫抑制的小鼠30 d后,显微镜下用细胞计数法计数免疫抑制小鼠血液中的白细胞数、淋巴细胞数和中性粒细胞数。结果 4种石斛0.25,0.50 g·kg^-1剂量均能显著增强T淋巴细胞增殖能力,并显著增加血液中的淋巴细胞数和巨噬细胞吞噬指数;铁皮石斛0.25,0.50 g·kg^-1剂量均能显著提高小鼠巨噬细胞吞噬率、血液中的白细胞数、中性粒细胞数;鼓槌石斛和流苏石斛0.50 g·kg^-1剂量能显著提高小鼠巨噬细胞吞噬率和血液中的白细胞数;金钗石斛0.50 g·kg^-1剂量能显著升高血液中的白细胞数。结论 4种石斛均能增强小鼠免疫功能,但铁皮石斛在增强巨噬细胞吞噬能力及提高免疫抑制小鼠血液中的中性粒细胞数方面效果优于另外3种石斛。     

HPLC测定毛兰素乳液型注射液中毛兰素及有关物质含量

目的 建立一种测定一类新药毛兰素乳液型注射液中毛兰素及有关物质鼓槌联苄含量的方法。方法 采用Agilent XDB C18柱(4.6 mm×250 mm,5 μm),流动相为甲醇-乙腈-水(30∶30∶40),检测波长：232 nm;流速：1.0 mL·min^-1。结果 毛兰素及有关物质鼓槌联苄达到完全分离;毛兰素在5.562 5~89.0 μg·mL-1内线性关系良好(Y=13 504X+2 146.6,r=0.999 9),平均回收率100.8%;有关物质鼓槌联苄在9.292~46.462 μg·mL^-1内亦有良好线性关系(Y=14.033 1X+2.388 6,r=0.999 9),平均回收率达99.8%。结论 本法灵敏,准确,专属性强,可用于测定注射液中毛兰素的含量和有关物质的检查。     

迭鞘石斛的化学成分研究

自兰科石斛属（Dendrobium）植物迭鞘石斛Dendrobium chryseum Rolfe中分得5个化合物，根据UV、IR、^1H NMR及^13C NMR确定其为β－谷甾醇，2，6－二甲氧基苯醌，鼓槌联苄，毛兰菲及鼓槌石斛素。这五种化合物均首次从该植物中分得。     

分蘖葱头中新黄酮苷的结构鉴定

目的　研究百合科植物分蘖葱头（Allium cepa L. var agrogatum Don）鳞茎的黄酮类化学成分。方法　利用Sephadex LH-20柱色谱进行分离纯化。从分蘖葱头中分离得到4个化合物,用IR,UV,MS,¹HNMR,¹³CNMR,¹H-¹H COSY,¹H-¹³C COSY和HMBC等光谱鉴定化合物。结果　经光谱鉴定化合物结构为：槲皮素3′-甲氧基-4′-O-β-D-葡吡喃糖苷(I)、山奈酚(II)、槲皮素4′-O-β-D-葡吡喃糖苷(III)和槲皮素3,4′-二-O-β-D-葡吡喃糖苷(IV)。结论　化合物I为新的黄酮苷类化合物,命名为分蘖葱头苷甲（Alliumoside A）; II,III和IV为首次从该植物中分得。     

高效液相色谱法测定复方联苯苄唑搽剂中联苯苄唑和氢化可的松的含量

目的 高效液相色谱法测定复方联苯苄唑搽剂中联苯苄唑和氢化可的松的含量。方法 用C₁₈色谱柱,流动相为乙腈-甲醇-0.5%醋酸铵(40∶40∶20),检测波长为253 nm,流量为1.0 ml·min^-1,柱温为35℃。结果 联苯苄唑和氢化可的松分别在19.912～99.56 mg·L^-1和19.776～98.88 mg·L^-1浓度范围内,与峰面积呈良好的相关性(r=0.999 9和r=0.999 8),平均回收率分别为99.4%(RSD为1.50%)和100.7%(RSD为1.42%)。结论 本法简便、快捷,结果准确,适用于该制剂的质量分析。     

2,4-二氨基5-氟-6-取代苄氨基喹唑啉的合成及生物活性

本文报道2,4-二氨基-5-氟-6-取代苄氨基喹唑啉类化合物的合成及抗疟、抗肿瘤和抗菌活性,这类化合物的合成是由5-氟-2,4,6-三氨基喹唑啉(6a)与取代苯甲醛缩合成Schiff碱,然后经还原、甲酰化、亚硝化或甲基化制得。5-氟-2,4,6-三氨基喹唑啉(6a)尚未见文献报道,由5-氟-2,4-二氨基喹唑啉(4)经硝化生成异构体5a和5b分离得5a后再经还原制得。经对伯氏鼠疟原虫Plasmodium berghei抑制性治疗筛选,有6个化合物I_2,4.5,6和II_5,6以每日1mg·kg^-1,给药4天,抑制率为100%;体外抗肿瘤活性以I4最强,对L1210白血病细胞的IC₅₀为9.86×10^-4μg·mL^-1,优于氨甲蝶呤(MTX);经对18种常见菌进行体外筛选,发现对肺炎双球菌Diplococcus pneumoniae活性较好。     

Synthesis and evaluation of 2,6-piperidinedione derivatives as potentially novel compounds with analgesic and other CNS activities

New 2,6-piperidinediones 2_a–g and 4_a–d were prepared by initial condensation of aromatic aldehydes or cycloalkanones with cyanoacetamide to give α-cyanocinnamides l_a–g or cycloalkylidenes 3_a,b which underwent Michae1 addition with ethyl cyanoacetate or diethylmalonate. Compounds 4_a–d were alkylated by various alkyl halides to produce the N-alkylated 2,6-piperidinedione derivatives 5_a–m. Some new selected compounds 2_a–c,f, 4_a–d & 5_e,h,j were pharmacologically evaluated for potential anticonvulsant, sedative and analgesic activities. These compounds exhibited significant anticonvulsant and analgesic effects after a single I.P. administration 100 mg/kg b.wt. . On the other hand all the investigated compounds induced hypnotic activity and prolonged the phenobarbital sodium- induced sleep as compared with the control group and the most potent compound was found to be 2_f.     

鼻渊净胶囊的HPLC指纹图谱研究

目的 建立鼻渊净胶囊的高效液相色谱（HPLC）指纹图谱。方法 采用Agilent SB-C₁₈（4.6 mm×250 mm,5 μm）色谱柱,乙腈-水为流动相、以1.0 ml/min流速行梯度洗脱,检测波长210 nm,柱温30 ℃,洗脱时间为80 min。采用中药色谱指纹图谱相似度评价系统（2004A版）对检测出色谱进行指纹图谱相似度评价。结果 建立了鼻渊净胶囊的HPLC指纹图谱,确定了20个共有峰,15个峰归属到各药材,其中5个峰确认了化学成分;10批样品的指纹图谱的整体相似度与对照图谱比较,均在90%以上。结论 所建立的鼻渊净胶囊指纹图谱有助于从整体上控制该制剂的质量。     

NEURAMIDE STIMULATES ADRENOCORTICOTROPIN BUT NOT PROLACTIN RELEASE FROM RAT PITUITARY

Neuramide (NMD), a substance found in crude preparations of porcine stomach extract, is a viral inhibitor that also has putative immunostimulatory effects. The effects of NMD on stress-hormone (ACTH and prolactin—PRL) release were assessed inin vivoandin vitrostudies. In the former, blood levels of corticosterone and PRL were measured in NMD-treated male rats.In vitroexperiments were performed to evaluate the effects of NMD and three of its fractions (obtained with high performance liquid chromatography) on ACTH and PRL release from perfused rat pituitary slices. NMD increased plasma corticosterone levelsin vivoand produced dose-dependent increases inin vitropituitary release of ACTH. No effects on PRL secretion were observedin vivoorin vitro. The stimulatory effects on ACTH release were caused by the NMD fraction with a molecular weight of >5000<10000Da.     

EFFECT OF POLICOSANOL SUCCESSIVE DOSE INCREASES ON PLATELET AGGREGATION IN HEALTHY VOLUNTEERS

Policosanol is a cholesterol-lowering drug with hypocholesterolemic effects demonstrated in experimental models, healthy volunteers and type II hypercholesterolemic patients. In addition, antiplatelet effects of policosanol have been shown in experimental models and healthy volunteers. The effect of successively increasing doses of policosanol on platelet aggregation was investigated in a randomized, placebo-controlled, double-blind study conducted in 37 healthy volunteers. The volunteers were on a placebo-baseline period (two tablets per day) for 7 days and thereafter they received randomly, under double-blind conditions, placebo or policosanol (10mgday⁻¹) for 7 days. After this period dosage was doubled to 20mgday⁻¹for the next 7 days and then again doubled to 40mgday⁻¹, while the control group received placebo tablets all the time. Platelet aggregation as well as coagulation time was measured at baseline and after each dosing step. Results showed that antiplatelet effects of policosanol were successfully enhanced throughout the study, thus suggesting a dose-dependent relationship. No significant effect was reached during the first dosing period, but significant reductions of epinephrine and ADP-induced platelet aggregation were observed after the second one. Finally, a significant inhibition of platelet aggregation induced by all the agonists was observed at the last dosing step. Coagulation time remained unchanged during the trial.     

Investigation of the prevalence of tetQ, tetX and tetX1 genes in Bacteroides strains with elevated tigecycline minimum inhibitory concentrations

In this study, the antibiotic susceptibilities to tigecycline and tetracycline of 35 selected Bacteroides fragilis group strains were determined by Etest, and the presence of tetQ, tetX, tetX1 and ermF genes was investigated by polymerase chain reaction (PCR). tetQ was detected in all 12 B. fragilis group isolates (100%) exhibiting elevated tigecycline minimum inhibitory concentrations (MICs) (≥8 μg/mL) as well as the 8 strains (100%) with a tigecycline MIC of 4 μg/mL, whilst tetX and tetX1 were present in 15% and 75% of these strains, respectively. All of these strains were fully resistant to tetracycline (MIC ≥ 16 μg/mL). On the other hand, amongst the group of strains with tigecycline MICs < 4 μg/mL (15 isolates), tetQ, tetX and tetX1 were found less frequently (73.3%, 13.3% and 46.7%, respectively). All but two strains harbouring the tetQ gene in this group were non-susceptible to tetracycline, with a MIC > 4 μg/mL. These data suggest that in most cases tigecycline overcomes the tetracycline resistance mechanisms frequently observed in Bacteroides strains. However, the presence of tetX and tetX1 genes in some of the strains exhibiting elevated MICs for tigecycline draws attention to the possible development and spread of resistance to this antibiotic agent amongst Bacteroides strains. The common occurrence of ermF, tetX, tetX1 and tetQ genes together predicted the presence of the CTnDOT-like Bacteroides conjugative transposon in this collection of Bacteroides strains.     

INDIRECT PARASYMPATHOMIMETIC ACTIVITY OF THE CLASS III ANTIARRHYTHMIC SUBSTANCE / -SOTALOLIN VITRO: REVERSIBLE INHIBITION OF CHOLINESTERASE ISOENZYMES FROM BLOOD AND THE HUMAN CENTRAL NERVOUS SYSTEM

Inhibitory effects of the class III antiarrhythmic compound / -sotalol on acetylcholinesterase (AChE; EC 3.1.1.7) isoenzymes of both erythrocytes and the human caudate nucleus and on serum cholinesterase (ChE; EC 3.1.1.8) were studiedin vitrousing a spectrophotometric kinetic assay with acetylthiocholine (ASCh) as substrate. Sotalol concentrations in the assays varied from 0.32 to 3.2m . All isoenzymes studied were inhibited by / -sotalol in a reversible and concentration-dependent manner. Double reciprocal plots of the reaction velocity against varying ASCh concentrations revealed that / -sotalol reduced substrate affinity (apparent Michaelis constant, KM, increased) of serum ChE, but did not change the enzyme's maximal rate of ASCh hydrolysis (V_max). Thus, / -sotalol inhibition of serum ChE was of the competitive type (rate constant for reversible competitive inhibition: K_i=0.51m ). In contrast, / sotalol reduced the maximal reaction velocity of the AChE isoenzyme from the central nervous system (caudate nucleus), but had no influence on substrate affinity of the enzyme (K_Mwith ASCh unchanged) indicating purely non-competitive inhibition kinetics (rate constant of reversible non-competitive inhibition: K_i′=0.44m ). / -sotalol inhibition of erythrocyte AChE was of mixed competitive/non-competitive type (K_i=0.31m , K_i′=0.49m ). Non-competitive / -sotalol inhibition of caudate nucleus AChE and the non-competitive component of erythrocyte AChE inhibition cannot be overcome by increased concentrations of the cholinergic transmitter acetylcholine (ACh). Peak / -sotalol plasma levels as described in the literature for both humans (15μ ) and experimental animals (dogs: 18μ ; rats: 260μ ) as well as maximal myocardial concentrations of the substance (dogs: 46μ ; rats: 478μ ) are in the range of about 2% to 100% of the sotalol inhibition rate constants determined in the present paper for cholinesterase isoenzymesin vitro. Thus, / -sotalol inhibition of ACh hydrolysisin vivomay contribute to both the well known antiarrhythmic potential and proarrhythmic side effects of the compound.     

AMELIORIATION OF CHEMICALLY-INDUCED HEPATOCYTE INJURY BY CYCLOSPORINE A

Cyclosporine A, beside its current applications, possesses potential hepatoprotective effects. This study was directed to investigate the effect of Cyclosporine A pretreatment on hepatic injury due to carbon tetrachloride (CCl₄) and -galactosamine. Rats were injected by two successive doses of Cyclosporine A (5mgkg⁻¹day⁻¹). Six hours after the second dose, 1mlkg⁻¹of CCl₄was administered i.p. Effects associated with Cyclosporine A pretreatment were examined by using isolated hepatocytes and hepatocytes that were immobilized and continuously perfused. -Galactosamine (5m ) was added directly to the perfusion medium. After isolation, hepatocytes were examined histologically by light and electron microscopy, immobilized and perfused for further metabolic functional activity evaluation. Cyclosporine A pretreatmentin vivoproduced hepatoameliorative effects of various degrees which were statistically significant as manifested by: (1) an increased trypan blue exclusion after CCl₄; (2) an improved ureagenesis after CCl₄; (3) a reduction in the lipid droplets accumulation in the cytoplasm produced by CCl₄administration; (4) well preserved cytoplasmic organelles as mitochondria, endoplasmic reticulum ER, nuclear chromatin structures that were altered by CCl₄; and (5) an increased hepatocytes survival in the agarose gel matrix, reduction of LD leakage and improvement of ureagenesis after -galactosamine addition to the perfusion medium. The beneficial effect of Cyclosporine A pretreatment in modifying hepatotoxicity of chemical insults merits further studies.     

栝楼不同药用部位质量控制的研究进展

瓜蒌子、瓜蒌皮、瓜蒌、天花粉来源于栝楼的不同药用部位,4味药材均为常用的大宗药材,现行版《中国药典》对其制定的质量标准过于简单,无法科学合理地控制其质量。本文对瓜蒌子、瓜蒌皮、瓜蒌、天花粉安全性和有效组分的研究进行综述,明确了相关研究存在的问题并针对问题提出建议,为科学全面的药材及饮片标准的制定提供参考依据。     

喙果黑面神化学成分研究

目的研究大戟科植物喙果黑面神(Breynia rostrata Merr.)的化学成分。方法利用硅胶、凝胶等色谱技术分离纯化化学成分,根据化合物的理化性质和光谱数据进行结构鉴定。结果从喙果黑面神的正丁醇萃取部分分离得到4个化合物,分别鉴定为6-O-甲基丙酰基-α-D-吡喃葡糖(6-O-methylpropanoyl-α-D-glucopyranose,1);4″-苯酚基-6-O-甲基丙酰基-β-D-吡喃葡糖苷(4″-phenolic-6-O-methylpropanoyl-β-D-glucopyranoside,2);1-O-没食子酰基-β-D-吡喃葡糖苷(1-O-galloyl-β-D-glucopyranoside,3);熊果苷(arbutin,4)。结论化合物1和2为新化合物,3和4均为首次从该种植物分离得到。     

EFFECTS OF 2-GUANIDINE-4-METHYLQUINAZOLINE ON GASTRIC ACID SECRETION IN RATS

In this study 2-guanidine-4-methylquinazoline (2-GMQ) appeared to decrease basal and stimulated gastric acid secretion, while structurally related compounds as dimethyl- biguanide, cyanoguanidine and 2-cyanoamino-4-methylpyrymidine did not. Thus, there is an antisecretory effect when the biguanide group is associated with a lipophilic structure. The antisecretive effects exerted by 2-GMQ are associated with anti H₂-histamine activity.The anti H₂-histamine nature of the effects of 2-GMQ was confirmed by the capacity of this compound of depressing the chronotropic activity of the isolated guinea pig auricle increased by histamine, as well as relaxant activity in rat uterus contracted by histamine, since both preparations are rich in H₂-histamine receptors.