灰树花多糖体外抑菌及抗氧化活性研究

目的 研究灰树花多糖的抑菌及抗氧化活性。方法 采用紫外分光光度法,以D-无水葡萄糖为对照品,测定灰树花提取物中多糖含量;采用纸片扩散法,以头孢哌酮为阳性对照,测量不同浓度灰树花多糖提取物金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌的抑菌圈直径;采用DPPH法和T-AOC试剂盒法,以清除率为指标,研究灰树花多糖的抗氧化活性。结果 灰树花提取物中多糖含量为53.49%;灰树花提取物对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌均有一定的抑菌作用,抑菌圈直径分别为13,11,10 mm;灰树花多糖浓度为0.05~10 mg·mL^-1时,对DPPH自由基具有一定的清除能力,当浓度高于0.5 mg·mL^-1时,开始显示出总抗氧化能力。结论 灰树花多糖具有一定的抑菌和抗氧化能力。     

白及花与块茎石油醚部位成分分析及其生物活性的比较研究

目的 分析白及花和块茎石油醚部位成分及生物活性。方法 以石油醚（60~90℃）为提取溶剂,采用索氏提取法提取白及花和块茎脂溶性成分,采用GC-MS分析其化学成分,通过滤纸片扩散法、CCK8法和分光光度法分别对其进行抑菌、抗肿瘤和α-淀粉酶抑制作用研究,通过检测DPPH自由基、ABTS自由基和羟自由基的清除率考察其体外抗氧化活性。结果 白及花和块茎中共鉴定出20种石油醚部位成分,其中花11种,块茎19种,共有成分10种,α-乙酰基-γ-丁内酯（15.20%,21.84%）和苄醇（12.07%,24.10%）为主要成分。白及花中石油醚部位成分的抑菌活性高于块茎,对枯草芽孢杆菌效果最好,最小抑菌浓度和最小杀菌浓度分别为0.41,0.51 g·L^-1和0.53,0.66 g·L^-1。当质量浓度为5.0 mg·mL^-1时,白及块茎石油醚部位成分对A₅₄₉细胞的抑制率为29.451%,高于花中石油醚部位成分27.621%的抑制率,前者对α-淀粉酶的IC₅₀为1.819 mg·mL^-1,后者的IC₅₀为2.028 mg·mL^-1。两者对DPPH自由基、ABTS自由基和羟自由基的清除率均随质量浓度的增大而增大,当浓度达到1.0 mg·mL^-1时,前者对ABTS自由基和羟自由基的清除率分别为99.67%和92.22%,高于后者90.07%和38.11%的清除率,后者对DPPH自由基的清除率为31.23%,高于前者18.94%的清除率,两者均低于Vc的清除率。结论 白及花和块茎中石油醚部位成分主要为酯类和醇类,2种石油醚部位成分均具有一定的生物活性,具有潜在的药用价值,并可为白及花的资源开发提供参考。     

木贼麻黄多糖的提取及体外抗氧化活性研究

目的 优化木贼麻黄多糖的提取工艺,初步研究木贼麻黄多糖的体外抗氧化活性。方法 采用热水浸提法提取木贼麻黄多糖,利用单因素试验结合响应面法对提取条件进行优化,并研究木贼麻黄多糖的体外抗氧化活性。结果 木贼麻黄多糖的最佳提取条件为：提取时间2.5 h,提取温度73℃,液料比25∶1,在此条件下多糖提取率为（5.57±0.072）%。木贼麻黄多糖对DPPH自由基和羟基自由基具有较强的清除能力,IC₅₀分别为703.9 μg·mL^-1和2 135.1 μg·mL^-1;对超氧阴离子自由基具有一定的清除能力,对Fe³⁺有一定的还原能力。结论 该提取工艺能较好地提取木贼麻黄多糖,所得木贼麻黄多糖具有一定的体外抗氧化能力,但活性低于同浓度的维生素C。     

HPLC测定人血浆中吡非尼酮浓度的不确定度评定

目的 建立HPLC测定人血浆中吡非尼酮浓度的不确定度分析方法。方法 分析HPLC测定吡非尼酮浓度的全过程,分析测量不确定度的来源和大小,量化各个测量不确定度分量,合成标准测量不确定度并报告扩展测量不确定度。结果 人血浆中低浓度（0.511 0 mg·mL^-1）、中浓度（2.038 mg·mL^-1）和高浓度（19.95 mg·mL^-1）的扩展不确定度分别为0.105 1,0.137 6,1.069 mg·mL^-1（P=95%）。结论 本方法不确定度来自标准曲线的拟合,其适用于HPLC测定人血浆吡非尼酮的不确定度评定。     

金莲花多糖提取工艺优化及其抗氧化活性评价

目的 优化金莲花多糖提取工艺,并分析测试金莲花多糖抗氧化活性。方法 采用回流提取法提取金莲花多糖,通过单因素考察料液比、提取温度、提取时间3个因素对金莲花多糖提取率的影响,并在此基础上通过正交实验设计对提取工艺进行优化。以DPPH自由基、ABTS+自由基、羟基自由基、超氧阴离子清除能力和总还原力为指标评价金莲花多糖的抗氧化活性。结果 金莲花多糖的最佳提取工艺为料液比1∶25、提取温度80 ℃、提取时间2 h,在此条件下金莲花多糖的提取率为1.350%±0.125%。体外抗氧化实验结果表明,金莲花多糖其DPPH自由基、ABTS+自由基、羟基自由基和超氧阴离子自由基清除率IC_{50分别为0.161、0.079、0.006、4.216 mg•mL^-1,且当浓度为4.0 mg•mL^-1时,总还原力为2.78。结论 优化的金莲花多糖提取工艺提取率较高且获得的金莲花多糖具有较好的抗氧化活性,对金莲花多糖的进一步开发利用提供了参考依据。}     

粉防已碱对大鼠心肌微粒体ATPases的作用

体外在常规反应条件下,粉防已碱(Tet)对大鼠心肌微粒体Na⁺,K⁺-ATPase活性无明显影响,但浓度依赖性抑制Mg²⁺-ATPase(IC₅₀=179μmol/L).Tet 10和100μmol/L使哇巴因(Oua)抑制Na⁺,K⁺-ATPase的量效曲线平行右移.Tet 100μmol/L可显著提高低K⁺或高Ca²⁺浓度时的Na⁺,K⁺-ATPase活性,但未能明显增加低Na⁺浓度时该酶的活性.动力学分析提示Tet 100μmol/L增加Na⁺,K⁺-ATPase对ATP的亲和力,但不改变其最大反应速度。     

酶法-超声提取黄精总黄酮及其抗氧化活性研究

目的 研究酶法-超声提取黄精中总黄酮（total flavonoids from Polygonatum sibirici,TFPS）的最佳工艺及总黄酮的体外抗氧化活性。方法 以总黄酮含量为指标,采用单因素和正交试验对纤维素酶用量、乙醇浓度、液料比和超声时间进行考察,优化工艺条件并考察总黄酮对DPPH自由基、ABTS⁺自由基的清除能力和亚铁离子螯合活性。结果 最佳提取条件：纤维素酶用量为0.75%,乙醇浓度为40%,液料比为20 mL·g^-1,超声时间30 min,总黄酮含量为1.595%。体外抗氧化试验表明,黄精总黄酮对DPPH自由基、ABTS⁺自由基有很强的清除能力,IC₅₀分别为27.55,11.47 μg·mL^-1,对亚铁离子的螯合活性较强,IC₅₀为32.26 μg·mL^-1。结论 酶法-超声提取工艺具有提取效率高、稳定性及重复性好等优点,可用于黄精中总黄酮的提取,在该工艺下提取的总黄酮具有较强的抗氧化活性。     

番薯藤提取物抗痤疮丙酸杆菌有效部位筛选研究

目的 研究番薯藤提取物对痤疮丙酸杆菌的体外抑菌作用,并对其有效部位进行筛选。方法 采用固体平板法、试管2倍比稀释法测定番薯藤水、醇提物对痤疮丙酸杆菌的抑菌圈大小和最低抑菌浓度（minimum inhibitory concentration,MIC）,采用系统溶剂法对番薯藤醇提物进行梯度提取,分别得到石油醚层、二氯甲烷层、乙酸乙酯层、正丁醇层和水层5个不同极性部位,并确定其有效部位及相应的MIC、最低杀菌浓度（minimum bactericidal concentration,MBC）。结果 番薯藤醇提物对痤疮丙酸杆菌有较强抑制作用,其MIC为50 mg·mL^-1。其中石油醚部位的抑菌作用最强,MIC为12.5 mg·mL^-1,MBC为25 mg·mL^-1;其次为正丁醇部位,MIC为25 mg·mL^-1,MBC为100 mg·mL^-1。结论 番薯藤醇提物对痤疮丙酸杆菌存在体外抑制作用,其有效成分主要集中于石油醚和正丁醇部位。     

响应面法优化地参多糖提取工艺及其抗氧化活性分析

目的 优化纤维素酶协同超声辅助提取地参多糖的工艺参数，并分析其抗氧化性。方法 在单因素试验基础上，以液料比（A）、纤维素酶用量（B）、超声功率（C）、超声温度（D）为自变量，以地参多糖提取量（Y）为响应值，采用4因素4水平的响应面分析法优化地参多糖提取工艺，同时测定地参多糖对DPPH自由基的清除能力。结果 纤维素酶协同超声辅助提取多糖的最佳工艺条件为：液料比60 mL·g^-1、纤维素酶用量3.6%、超声功率300 W、超声温度30℃、超声时间40 min，在此条件下，地参多糖提取量为（378.56±1.346）mg·g^-1，与预测值（381.68 mg·g^-1）接近。地参多糖对DPPH自由基有较强的清除能力，且随多糖质量浓度的增加而逐渐增强；地参多糖质量浓度为0.420 mg·mL^-1时，清除率为91.36%。结论 采用响应曲法优化的多糖提取工艺参数准确可靠，可用于地参多糖提取；地参多糖具有较强的体外抗氧化能力。     

四肽FMRFa对大鼠心室肌Na+/Ca2+交换的抑制

目的　研究四肽FMRFa对大鼠单个心室肌细胞Na⁺/Ca²⁺交换的作用。方法　用膜片钳全细胞记录法测定成年大鼠心室肌细胞Na⁺/Ca²⁺交换电流(I_Na⁺/Ca²⁺)和其他离子通道电流。结果　FMRFa对大鼠心室肌细胞I_Na⁺/Ca²⁺呈浓度依赖性抑制,100μmol·L^-1浓度时抑制内向和外向I_Na⁺/Ca²⁺密度分别达60.1%和56.5%,对内向电流及外向电流的IC₅₀分别为20μmol·L^-1和34μmol·L^-1。FMRFa5μmol·L^-1抑制I_Na⁺/Ca²⁺内向和外向电流密度分别为38.7%和34.9%,但FMRFa5μmol·L^-1及20μmol·L^-1对L型钙电流、钠电流、瞬时外向电流和内向整流钾电流均无显著抑制作用。结论　FMRFa对大鼠心室肌细胞是一个特异性Na⁺/Ca²⁺交换抑制剂。     

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,5μm)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...     

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.     

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.     

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。