水飞蓟宾抑制人肺癌细胞浸润的作用机制研究

目的通过观察水飞蓟宾对有高转移能力的人肺癌细胞A549相关酶的作用来研究水飞蓟宾对浸润和运动性的影响。方法应用细胞活性测定、细胞浸润和运动性分析、细胞-基质黏附实验、逆转录聚合酶链反应等技术完成实验。结果A549细胞用高达100μM的不同浓度的水飞蓟宾处理一定时间后,行明胶酶谱、酪蛋白酶谱以及蛋白印迹分析来确定水飞蓟宾对金属蛋白酶-2（MMP-2）的影响。结论水飞蓟宾治疗可以浓度以及时间依存性方式减少MMP-2表达。半定量RT—PCR分析进一步表明,水飞蓟宾可在转录水平调节MMP-2表达。     

水飞蓟宾及其类似物的化学修饰研究进展

以天然黄酮类化合物为活性先导物,研究其化学结构与生物活性的关系,进而进行化学修饰研究,是目前创新药物的一条重要思路。药用植物水飞蓟用来治疗肝胆疾病已有2000多年的历史,水飞蓟宾作为水飞蓟素的主要活性成分具有保肝、抗炎和抗癌等活性而备受人们关注,但由于水飞蓟宾极低的溶解性极大地限制了其生物利用度。为此,国内外学者通过化学和物理等方法对其进行修饰和改造,并取得了一定的成果。本文就近10年来水飞蓟宾及其类似物的化学修饰研究进行综述。     

水飞蓟宾乳糖苷的合成、表征及抗氧化活性研究

实验设计旨在提高水飞蓟宾的水溶性、生物活性,以水飞蓟宾和乳糖苷为原料合成水飞蓟宾乙酰乳糖苷和水飞蓟宾乳糖苷.采用IR、1H NMR、13C NMR及HPLC-MS等手段对产物进行结构表征,并测定了水飞蓟宾乳糖修饰物的还原能力,清除DPPH自由基,清除ABTS+自由基能力及抑制脂质过氧化能力.结果表明水飞蓟宾乳糖苷的抗氧化活性显著优于水飞蓟宾.     

水飞蓟宾诱导肺腺癌Anip973 细胞凋亡的分子机制研究

目的:探讨水飞蓟宾诱导肺腺癌Anip973细胞系细胞凋亡的分子机制。方法:采用MTT法、倒置显微镜和电子显微镜等形态学检测以及流式细胞仪(FCM)技术检测、DNALadder分析、凋亡分子PARP的表达检测细胞凋亡,同时进行凋亡相关蛋白Bax、Bcl-2、caspase-3和caspase-9表达活性分析。结果:(1)水飞蓟宾对人肺腺癌Anip973细胞系细胞的增殖有显著抑制作用;(2)水飞蓟宾作用Anip973细胞48h后,随着浓度的增加,倒置显微镜下可见细胞数目减少,胞体变小、变圆,到高浓度时出现较多的死亡细胞;(3)扫描电镜观察发现,随着水飞蓟宾作用浓度的增加,Anip973细胞中出现增多的凋亡细胞,凋亡细胞表现出典型的超微结构特征;(4)流式细胞仪检测的结果发现,随着药物作用时间的延长,Anip973细胞的G1期细胞比例增多,S期细胞明显减少,G2期细胞略有减少,并出现明显的凋亡峰。(5)水飞蓟宾作用后的Anip973细胞出现明显的DNALadder和PARP降解增加等凋亡特征;(6)水飞蓟宾作用后,Anip973细胞中的凋亡相关蛋白Bax表达增加、caspase-3和caspase-9酶活性增加,而Bcl-2表达降低。结论:水飞蓟宾在体外有抑制人肺腺癌细胞Anip973的增殖作用,并通过激活线粒体依赖的caspase凋亡通路,诱导其凋亡。     

水飞蓟宾诱导肺腺癌Anip973细胞凋亡的分子机制研究

目的：探讨水飞蓟宾诱导肺腺癌Anip973细胞系细胞凋亡的分子机制。方法：采用MTT法、倒置显微镜和电子显微镜等形态学检测以及流式细胞仪（FCM）技术检测、DNALadder分析、凋亡分子PARP的表达检测细胞凋亡,同时进行凋亡相关蛋白Bax、Bcl-2、caspase-3和caspase-9表达活性分析。结果：（1）水飞蓟宾对人肺腺癌Anip973细胞系细胞的增殖有显著抑制作用;（2）水飞蓟宾作用Anip973细胞48h后,随着浓度的增加,倒置显微镜下可见细胞数目减少,胞体变小、变圆,到高浓度时出现较多的死亡细胞;（3）扫描电镜观察发现,随着水飞蓟宾作用浓度的增加,Anip973细胞中出现增多的凋亡细胞,凋亡细胞表现出典型的超微结构特征;（4）流式细胞仪检测的结果发现,随着药物作用时间的延长,Anip973细胞的G1期细胞比例增多,S期细胞明显减少,G2期细胞略有减少,并出现明显的凋亡峰。（5）水飞蓟宾作用后的Anip973细胞出现明显的DNALadder和PARP降解增加等凋亡特征;（6）水飞蓟宾作用后,Anip973细胞中的凋亡相关蛋白Bax表达增加、caspase-3和caspase-9酶活性增加,而Bcl-2表达降低。结论：水飞蓟宾在体外有抑制人肺腺癌细胞Anip973的增殖作用,并通过激活线粒体依赖的caspase凋亡通路,诱导其凋亡。     

水飞蓟素提取工艺的改进和探讨

对水飞蓟种皮中的水飞蓟素提取方法进行初步研究。实验采用乙酸乙酯超声波辅助浸提,水飞蓟素提取率可达到7．0％以上,且缩短提取时间（〈10h）,在甲醉体系下3次重结晶,水飞蓟宾纯度可达到97．0％。原料收率为7．07mg／g。研究认为,水飞蓟种子皮壳分离对提高产品质量和资源利用价值有显著意义。     

水飞蓟宾诱导卵巢癌HO-8910细胞凋亡增殖及其机制探讨

目的:探讨水飞蓟宾对人卵巢癌HO-8910细胞增殖的抑制作用及其作用机制。方法:HO-8910细胞分为四组:(1)对照组;(2)水飞蓟宾低浓度组;(3)水飞蓟宾中浓度组;(4)水飞蓟宾高浓度组。通过MTT法测定细胞增值率,流式细胞技术检测细胞凋亡情况,Hoechst染色观查细胞核凋亡,Western-blot检测bax及bcl-2表达。结果:细胞增殖检测结果显示,水飞蓟宾低、中、高浓度组的抑制率(83.00±5.51%、65.33±3.48%、56.67±4.37%)与对照组(97.33±4.25%)比较差异具有统计学意义(P0.05)。流式细胞技术结果显示,水飞蓟宾低、中、高浓度组凋亡细胞比例分别为16.93±2.34%、26.20±2.21%和37.93±1.98%,与对照组(1.43±0.72%)相比差异均有统计学意义(P0.05)。Hoechst染色结果显示,水飞蓟宾低、中、高浓度组凋亡细胞比例分别为12.56±2.55%、25.73±2.05%和39.14±3.69%,与对照组(0.54±0.67%)相比差异均有统计学意义(P0.05)。此外,水飞蓟宾可以升高bax基因表达水平,降低bcl-2基因表达平。结论:水飞蓟宾能明显抑制HO-8910细胞增殖,促进细胞凋亡,通过改变凋亡因子表达诱导卵巢癌HO-8910细胞凋亡。     

不同产地水飞蓟药材HPLC指纹图谱研究

目的建立水飞蓟药材的HPLC指纹图谱分析方法,并对不同产地水飞蓟药材进行指纹图谱比较研究。方法采用反相高效液相色谱法,Shimadzu C18(150 mm×4.6 mm)为色谱柱,流动相为甲醇-水-冰醋酸(48:52:1),流速:1.0 mL/min,检测波长为287 nm,柱温40℃,进样量10μl。对水飞蓟药材的指标成分水飞蓟宾进行了定性定量,并以相似度鉴别药材质量。结果建立了水飞蓟药材的HPLC指纹图谱,标定了12个共有峰,方法学考察结果符合指纹图谱技术要求,经相似度计算11个不同产地药材之间的相似性均高于0.944。结论本法简便准确、结论可靠,可用于不同产地水飞蓟药材的指纹图谱测定和质量评价,为有效控制水飞蓟药材的内在质量提供了实验依据。     

氨茶碱,环磷酸泉苷葡甲胺（MCA）对兔膈肌功能的影响

目的：观察氨茶碱、环磷酸腺苷葡甲胺对兔跨膈压及膈肌电活动的影响,以中肌疲劳的治疗效果提供实难依据。方法：刺激双侧膈神经４０ｍｉｎ复制膈肌疲劳（ＤｉＦ）动物模型,动物随机分三组（ｎ＝６）：氨茶碱组（１０ｍｇ／ｋｇ）、ＭＣＡ组（１０ｍｇ／ｋｇ）,合用组（氨茶碱１０ｍｇ／ｋｇ＋葡甲胺ｃＡＭＰ（１０ｍｇ／ｋｇ）。于ＤｉＦ前、ＤｉＦ及给药后３０、６０ｍｉｎ记录中压（Ｐｄｉ）;记录膈肌肌电图（ＥＭＧｄｉ）并输     

水飞蓟宾通过抑制Notch1信号通路发挥抗食管癌EC109细胞的作用

目的:探讨水飞蓟宾(silybin,SIL)对人食管癌EC109细胞系的作用,并探求Notch1以及凋亡通路在其中的角色。方法:实验分为对照组和SIL处理组(75、150、300μM),各组细胞分别处理12、24、36小时。Cell Counting Kit-8(CCK-8)测细胞活力;粘附实验测细胞粘附能力;Caspase-Glo誖3/7定量试剂盒测细胞Caspase3/7的表达;Western-blot测Notch1、Bcl2和Bax蛋白表达。结果:CCK-8检测结果示SIL可有效抑制EC109细胞的活力(P0.01),并呈浓度时间依赖性;粘附实验结果示SIL可以降低EC109细胞粘附能力(P0.01);Caspase3/7检测结果示SIL可以使EC109细胞Caspase3/7活性升高(P0.01);Western-blot检测结果显示SIL可以使EC109细胞Notch1和Bcl2表达下降,Bax表达上升(P0.01)。结论:SIL可有效抑制食管癌EC109细胞活力,其作用机制可能与抑制Notch1通路,激活凋亡通路相关,SIL可能是食管癌药物治疗领域具有开发前景的药物。     

Imidacloprid and Related Compounds: Structure and Water Solubility of N-Alkyl Derivatives of Imidacloprid

An intramolecular hydrogen bond between NH???O₂N in insecticide, imidacloprid (1), and its nitromethylene analog 15 was proved by NMR and IR spectra. That electron delocalization over their planar moieties was disrupted by alkylation at the imidazolidine nitrogen atom is demonstrated by the hypsochromic shifts in UV and deshielding effect in NMR spectra. Interestingly, the N-alkyl derivatives (C1-5) had greater water solubility than 1, although increasing alkyl chain length decreased the solubility. The hydrophilicity of the alkyl derivatives would result from remote charge heads being formed as a result of the conjugation disruption by alkylation, while the hydrophobicity of 1 could be ascribed to the charge distribution over the conjugated system coupled with the intramolecular H-bonding. The greater water solubility of 15 than 1 and contrastively small solubility of the cyanoimine analogue are discussed based on the difference in their steric crowding.     

Structure and properties of rat thymus deoxyribonucleoprotein. Solubility properties and effects of precipitation

1. Deoxyribonucleoprotein was prepared from rat thymus and was studied chiefly by the method of electric birefringence. The birefringence depends on the electrical and optical properties of the molecules and on their volume; the decay time of birefringence (after the removal of the electric field) depends on molecular length. 2. A comparison was made of the properties of deoxyribonucleoprotein redissolved after precipitation in 0.15m-sodium chloride with those of the original material, the main object being to find if structural changes have occurred in the former. As a preliminary, the dependence of the solubility of the deoxyribonucleoprotein on the concentration of added salt was investigated, and the birefringence properties were also studied after the addition of sodium chloride at low concentrations, after the alteration of pH and after dialysis. 3. It was found that precipitation of deoxyribonucleoprotein occurs in two fractions, beginning at about 0.4mm-sodium chloride. The solubility is minimal at about 0.15m-sodium chloride. 4. The electric birefringence and decay time of the deoxyribonucleoprotein decrease with increasing concentration of added sodium chloride, and the birefringence also decreases after dialysis. Prolonged dialysis leads to precipitation. 5. The properties of deoxyribonucleoprotein redissolved after precipitation with 0.15m-sodium chloride differ considerably from those of the original deoxyribonucleoprotein. This is attributed to some type of disorganization process occurring during precipitation. It is concluded that the organization of the original structure is very specific.     

Biochar in Co-Contaminated Soil Manipulates Arsenic Solubility and Microbiological Community Structure,and Promotes Organochlorine Degradation

We examined the effect of biochar on the water-soluble arsenic (As) concentration and the extent of organochlorine degradation in a co-contaminated historic sheep-dip soil during a 180-d glasshouse incubation experiment. Soil microbial activity, bacterial community and structure diversity were also investigated. Biochar made from willow feedstock (Salix sp) was pyrolysed at 350 or 550°C and added to soil at rates of 10 g kg^-1 and 20 g kg^-1 (representing 30 t ha^-1 and 60 t ha^-1). The isomers of hexachlorocyclohexane (HCH) alpha-HCH and gamma-HCH (lindane), underwent 10-fold and 4-fold reductions in concentration as a function of biochar treatment. Biochar also resulted in a significant reduction in soil DDT levels (P < 0.01), and increased the DDE:DDT ratio. Soil microbial activity was significantly increased (P < 0.01) under all biochar treatments after 60 days of treatment compared to the control. 16S amplicon sequencing revealed that biochar-amended soil contained more members of the Chryseobacterium, Flavobacterium, Dyadobacter and Pseudomonadaceae which are known bioremediators of hydrocarbons. We hypothesise that a recorded short-term reduction in the soluble As concentration due to biochar amendment allowed native soil microbial communities to overcome As-related stress. We propose that increased microbiological activity (dehydrogenase activity) due to biochar amendment was responsible for enhanced degradation of organochlorines in the soil. Biochar therefore partially overcame the co-contaminant effect of As, allowing for enhanced natural attenuation of organochlorines in soil.     

Solubility of proteins

A theory is presented on the solubility of proteins, in the hydrated as well as in the dry state, and in water as well as in organic solvents. To this effect, colloidal stability is assimilated with the solubility of the proteins, considered as hydrated entities. By means of a surface thermodynamic approach it can be shown that an increase in size of a hydrated protein must lead to insolubility, even in the absence of any change in a protein's surface properties. This can be substantiated experimentally by comparing the surface properties of immune complexes with those of their constituent immunoglobulins, as well as by comparing some of the properties of intact tobacco mosaic virus with those of its monomeric capsid subunits. Insolubilization of proteins by means of charge interactions as well as by dehydration is studied; an explanation is given of why precipitation caused by charge interactions is more likely to lead to partial irreversible denaturation than precipitation caused by protein-protein interactions brought about by partial dehydration (e.g., by salting-out). A link is established between the smallness (or even the negative value) of the interfacial tension between given proteins and various solvents and their solubility in these solvents. The energy of hydration of proteins can also be measured, and the differences between the free energies of interaction of dried and hydrated proteins with water point toward the additional processes underlying the solubilization, i.e., toward the conformational change of a protein in the process of becoming hydrated. The parameter of conformational change of a protein, while becoming hydrated, appears to be more closely linked to its degree of hydration than to its hydration energy.     

Solubility of proteins

A theory is presented on the solubility of proteins, in the hydrated as well as in the dry state, and in water as well as in organic solvents. To this effect, colloidal stability is assimilated with the solubility of the proteins, considered as hydrated entities. By means of a surface thermodynamic approach it can be shown that an increase in size of a hydrated protein must lead to insolubility, even in the absence of any change in a protein's surface properties. This can be substantiated experimentally by comparing the surface properties of immune complexes with those of their constituent immunoglobulins, as well as by comparing some of the properties of intact tobacco mosaic virus with those of its monomeric capsid subunits. Insolubilization of proteins by means of charge interactions as well as by dehydration is studied; an explanation is given of why precipitation caused by charge interactions is more likely to lead to partial irreversible denaturation than precipitation caused by protein-protein interactions brought about by partial dehydration (e.g., by “salting-out”). A link is established between the smallness (or even the negative value) of the interfacial tension between given proteins and various solvents and their solubility in these solvents. The energy of hydration of proteins can also be measured, and the differences between the free energies of interaction of dried and hydrated proteins with water point toward the additional processes underlying the solubilization, i.e., toward the conformational change of a protein in the process of becoming hydrated. The parameter of conformational change of a protein, while becoming hydrated, appears to be more closely linked to its degree of hydration than to its hydration energy.     

Solubility and dissolution of iron oxides

In most soils, FeIII oxides (group name) are the common source of Fe for plant nutrition. Since this Fe has to be supplied via solution, the solubility and the dissolution rate of the Fe oxides are essential for the Fe supply. Hydrolysis constants and solubility products (K_sp) describing the effect of pH on FeIII ion concentration in solution are available for the well-known Fe oxides occurring in soils such as goethite, hematite, ferrihydrite. K_sp values are usually extremely low ((Fe³⁺)·(OH)³=10^–37–10^–44). However, for each mineral type, K_sp may increase by several orders of magnitude with decreasing crystal size and it decreases with increasing Al substitution assuming ideal solid solution between the pure end-members. Based on such calculations a poorly crystalline goethite with a crystal size of 5 nm may well reach the solubility of ferrihydrite. The variations in K_sp are of relevance for soils because crystal size and Al substitution of soil Fe oxides vary considerably and can now be determined relatively easily.The concentration of Fe²⁺ in soil solutions is often much higher than that of Fe(III) ions. Therefore, redox potential strongly influences the activity of FeII. At a given pH and E_h, the activity of FeII is higher the higher K_sp of the FeIII oxide and thus also varies with the type of Fe oxide present.Besides the solubility, it is the dissolution rate which governs the supply of soluble Fe to the plant roots. Dissolution of Fe oxides takes place either by protonation, complexation or, most important, by reduction. Numerous dissolution rate studies with various FeIII oxides were conducted in strong mineral acids (protonation) and they have shown that besides the Fe oxide species, crystal size and/or crystal order and substitution are important determinative factors. For example, in soils, small amounts of a more highly soluble meta- or instable Fe oxide such as ferrihydrite with a large specific surface (several hundred m²g^–1) may be essential for the Fe supply to the plant root. Its higher dissolution rate can also be used to quantify its amount in soils. Ferrihydrite can be an important component in soils with high amounts of organic matter and/or active redox dynamics, whereas highly aerated and strongly weathered soils are usually very low in ferrihydrite. On the other hand, dissolution rates of goethites decrease as their Al substitution increases.Much less information exists on the rate of reductive and chelative dissolution of Fe oxides which generally simulate soil conditions better than dissolution by protonation. Here again, type of oxide, crystal size and substitution are important factors. Organic anions such as oxalate, which are adsorbed at the surface, may weaken the Fe³⁺-O bonds and thereby increase reductive dissolution. As often observed in weathering, the dissolution features of the crystals appear to follow zones of weakness in the crystal.     

Effect of Cyclodextrin Complexation on the Aqueous Solubility and Solubility/Dose Ratio of Praziquantel

Praziquantel (PZQ), the primary drug of choice in the treatment of schistosomiasis, is a highly lipophilic drug that possesses high permeability and low aqueous solubility and is, therefore, classified as a Class II drug according to the Biopharmaceutics Classification System (BCS). In this work, β-cyclodextrin (β-CD) and hydroxypropyl-β-cyclodextrin (HP-β-CD) were used in order to determine whether increasing the aqueous solubility of a drug by complexation with CDs, a BCS-Class II compound like PZQ could behave as BCS-Class I (highly soluble/highly permeable) drug. Phase solubility and the kneading and lyophilization techniques were used for inclusion complex preparation; solubility was determined by UV spectroscopy. The ability of the water soluble polymer polyvinylpyrolidone (PVP) to increase the complexation and solubilization efficiency of β-CD and HP-β-CD for PZQ was examined. Results showed significant improvement of PZQ solubility in the presence of both cyclodextrins but no additional effect in the presence of PVP. The solubility/dose ratios values of PZQ-cyclodextrin complexes calculated considering the low (150 mg) and the high dose (600 mg) of PZQ, used in practice, indicate that PZQ complexation with CDs may result in drug dosage forms that would behave as a BCS-Class I depending on the administered dose.     

Solubility of plant invertases

Solubilization of acid invertase associated with cell wall preparations from aged slices of Jerusalem artichoke tuber tissue was achieved at high ionic