流动注射双安培法测定橙皮甙

基于橙皮甙的不可逆氧化和氧化铂的不可逆还原体系构成了双安培法直接检测橙皮甙的新方法。在外加电压为0.2 V时,通过偶合橙皮甙在一支电极上的氧化和氧化铂在另一支电极上的还原两个不可逆电极过程,构成流动注射双安培检测体系。在pH 8.95的B-R缓冲溶液中,测得橙皮甙的氧化电流与其浓度在6.0×10-6~8.0×10-4mol/L范围内呈良好的线性关系(r=0.9997,n=11),检出限为1.0×10-6mol/L。连续30次测定6.0×10-4mol/L橙皮甙,其峰电流相对标准偏差(RSD)为3.2%,常用药物赋形剂和无机离子均不干扰橙皮甙的测定。方法已用于江中健胃消食片中橙皮甙含量的测定。     

碳糊电极阴极吸附伏安法测定橙皮甙

在0.4mol/L的NH4Cl-NH3(pH9.0)缓冲液中,使用JP-303极谱分析仪,橙皮甙在碳糊电极(CPE)上有一灵敏的吸附伏安还原峰,峰电位为-1.2V(vs.SCE).该还原峰的二阶导数峰电流与橙皮甙的浓度在2.0×10-8～1.0×10-6mol/L(富集90s)范围内成良好的线性关系,相关系数为0.9963,检出限为1.0×10-8mol/L(S/N=3,富集110s).探讨了橙皮甙在碳糊电极上的伏安性质和电极反应机理,并且成功应用于中草药桔皮中橙皮甙含量的测定.     

荧光光谱法研究橙皮甙与牛血清白蛋白的相互作用

在pH7.40的Tris-HCl 缓冲体系中,采用荧光光谱技术研究了橙皮甙与牛血清白蛋白(BSA)的相互作用.随着温度升高,橙皮甙与BSA 的猝灭常数逐渐增加.实验表明:橙皮甙对BSA的荧光猝灭为动态猝灭过程.由热力学参数焓变(△H=70.71 kJ/mol)大于零和熵变[△S=316.29J/(mol·K)]大于零,...     

中草药有效成分橙皮甙的固体表面延迟荧光法研究

本文以层析聚配角安膜为基质，用乙酸锂作增强剂，建立了测定痕量中草药有效成分橙皮甙的固体表面延荧光法。该法取样量少，线性范围宽，灵敏度高，操作简便快速。     

反相高效液相色谱法同时测定柚皮中柚皮甙和橙皮甙的含量

采用反相高效液相色谱法同时测定柚皮中柚皮甙和橙皮甙的含量。色谱条件:μ-BondapakC18柱(250mm×4.6mm,5μm),流动相为甲醇-0.5%乙酸溶液(V/V=38/62);流速为0.8mL·min-1;检测波长为283nm,柱温为25℃。柚皮甙和橙皮甙的线性范围分别为20-60mg·L-1和10-30mg·L-1。柚皮甙和橙皮甙的平均回收率分别为99.3%和97.8%。该方法具有快速,结果准确等优点。     

反相高效液相法测定枳实、枳壳中橙皮甙和柚皮甙的含量

 采用高效液相法测定了枳实和枳壳中的橙皮甙和柚皮甙含量。柱为HypersilODS1柱(250mm×4 6mmi d ),流动相为乙腈 0 5%乙酸溶液(体积比为22∶78),流速为1 0mL/min,检测波长为283nm。柚皮甙和橙皮甙的线性范围分别为0 060g/L～0 604g/L和0 0125g/L～0 125g/L,柚皮甙和橙皮甙的平均回收率分别为97 1%和95 3%。该方法具有操作简便、分析快速、准确等优点。     

蜜炼川贝枇杷膏中橙皮甙含量的固相萃取-高效液相色谱法测定

建立了蜜炼川贝枇杷膏中橙皮甙含量测定方法，样品用流动相溶解定溶后，注入Sep-Pak C18固相萃取微柱，取其达到吸附平衡后的流出液作为反相高效液相色谱法测定用的供试液，克服了高糖含量基质条件下液－液萃取法存在的提取不完全的现象；在3．265－32．65mg/L范围内，橙皮甙进样量与峰面积响应值呈良好的线性关系，r＝0．9999；回收率为98％－102％，RSD为1．6％（n=5）；结果表明，该法简便快速，分析结果准确可靠，重复性好，可用作蜜炼川贝枇杷膏的质量控制方法。     

橙皮甙、柚皮甙、橙皮素和柚皮甙元4种物质的毛细管电泳分离及测定

通过优化缓冲溶液pH和浓度、分离电压和进样时间等条件,建立了橙皮甙、柚皮甙、橙皮素和柚皮甙元4种物质的毛细管电泳分离分析方法.在优化的条件下10 min内实现了4种物质的毛细管电泳分离.橙皮甙、柚皮甙、橙皮素和柚皮甙元4种物质分别在0.03～0.80、0.03～0.85,0.02～0.60和0.02～0.65mg/mL浓度范围内和峰电流成线性关系,检出限分别为0.007、0.006、0.004和0.005 mg/mL.方法用于分析模拟样品得到满意的结果,有望用于实际样品分析.     

N-氧化吡啶-2-甲醛缩二胍合铜配合物的合成、表征及磁性

合成了N-氧化吡啶-2-甲醛缩二胍合铜的新型配合物,通过元素分析、红外光谱、电导、热重测定,对配合物进行了表征,并测定了配合物的变温磁化率,表明双核配合物中铜离子间存在反铁磁性交换作用.     

铜（Ⅱ）－α－氨基酸配合物的离解动力学研究

铜（Ⅱ）－α－氨基酸配合物的离解动力学研究吴宝璋（厦门大学化学系厦门８６１００５）关键词铜配合物，金属－氨基酸相互作用，生物配体，配合物离解动力学铜是生命体系中最重要的微量元素之一，由于生理上的原因，动物体内铜离子的补给宜用它的配合物，而不是简单的盐...     

Curcumin Inhibits Lysophosphatidic Acid Mediated MCP-1 Expression via Blocking ROCK Signalling

Curcumin is a natural compound that has been widely used as a food additive and medicine in Asian countries. Over several decades, diverse biological effects of curcumin have been elucidated, such as anti-inflammatory and anti-oxidative activities. Monocyte chemoattractant protein-1 (MCP-1) is a key inflammatory marker during the development of atherosclerosis, and curcumin blocks MCP-1 expression stimulated by various ligands. Hence, we studied the action of curcumin on lysophosphatidic acid (LPA) mediated MCP-1 expression and explored the specific underlying mechanisms. In human vascular smooth muscle cells, LPA induces Rho-associated protein kinase (ROCK) dependent transforming growth factor receptor (TGFBR1) transactivation, leading to glycosaminoglycan chain elongation. We found that LPA also signals via the TGFBR1 transactivation pathway to regulate MCP-1 expression. Curcumin blocks LPA mediated TGFBR1 transactivation and subsequent MCP-1 expression by blocking the ROCK signalling. In the vasculature, ROCK signalling regulates smooth muscle cell contraction, inflammatory cell recruitment, endothelial dysfunction and vascular remodelling. Therefore, curcumin as a ROCK signalling inhibitor has the potential to prevent atherogenesis via multiple ways.     

Pharmacological activities of the prenylcoumarins, developed from folk usage as a medicine of Peucedanum japonicum THUNB

In connection with the chemical structure of coumarin 1 (a mixture of acetylangeloylkhellactone and acetyltigloylkhellactone), a compound isolated from Peucedanum japonicum THUNB., we synthesized eight coumarin compounds (3-10) and performed pharmacological studies on these nine compounds, as well as on another coumarin, praeruptorin A (= Pd-Ia) (2), a compound isolated from Peucedanum praeruptorum DUNN. We studied the effects of compounds 1-5 on isolated smooth muscle and of compounds 1-10 on the cardiovascular system. These compounds showed dose-related antagonistic effects on histamine- and Ca(2+)-induced contractions in smooth muscle and the potencies were in the order 2 greater than 1 greater than seselin (3) greater than xanthyletin (4) = 2.2.10-trimethyl-2H,8H-benzo[1,2-b: 3,4-b']dipyran-8-one (5). All the compounds except 7-geranyloxy-4-methylcoumarin (10) produced a dose-related increase in vertebral, carotid and femoral blood flow. Compounds 1, 5, and 4-methyl-7-(3-methyl-2-butenyloxy)coumarin (8) caused an increase in blood pressure, but 3 and 4 caused a slight decrease. Compounds 2, 3, 4, 5, and 8 increased heart rate. Jatamansinone (6) and jatamansinol (7) caused only slight changes in blood pressure. All the compounds except 10 increased heart rate. Compound 1 also increased blood flow in the cerebral cortex. Thus, compound 1 was confirmed to have an inhibitory effect on contraction in isolated smooth muscle and an action increasing arterial blood flow. Among the compounds tested in this study, 3, as well as 6 and 7 synthesized on the basis of 3, showed actions similar to those of Ca2+ blockers and some compounds had papaverine-like activities.(ABSTRACT TRUNCATED AT 250 WORDS)     

Identification of metabolites of 4,4'-methylenedianiline in vascular smooth muscle cells by liquid chromatography-electrospray tandem mass spectrometry

A capillary liquid chromatography-electrospray tandem mass spectrometry (LC-ES-MS/MS) method was developed for the identification of metabolites of 4,4'-methylenedianiline (diaminodiphenyl methane, (DAPM)) derived from exposure of vascular smooth muscle cells (VSMC) to this compound. The use of precolumn concentration and column switching techniques prior to reversed-phase liquid chromatography coupled online to ES-MS enabled the separation and detection of low-level DAPM and its metabolites in the exposed cell samples. The employed LC-ES-MS method, and further LC-ES-MS/MS analysis enabled the structural assignments for two DAPM metabolites from vascular smooth muscle cells: N-acetyl methylenedianiline (N-acetyl-DAPM) and N,N'-diacetyl methylenedianiline (N,N'-diacetyl-DAPM).     

Chemical constituents from rauvolfia verticillata and bioactivities research

A new acridone alkaloid, named 9-hydroxynoracronycine (1), together with four known compounds, including coumarins, lignan, and indole alkaloid, was isolated and identified from the roots and rhizomes of Rauvolfia verticillata. The structure of the new compound was determined by spectroscopic means (UV, IR, MS, and NMR). The acridone alkaloid and coumarins were identified as new constituents of Rauvolfia genus. The cytotoxic activities of the new compound were tested against human breast cancer cell line MCF-7 and human promyelocytic leukemia HL-60. Results showed that compound 1 decreased MCF-7 cell proliferation in a statistically IC₅₀ significant manner at 102.8 μmol/L. In addition, compound 1 exhibited moderate small intestine smooth muscle relaxation.     

Potential role of HMG CoA reductase inhibitor on oxidative stress induced by advanced glycation endproducts in vascular smooth muscle cells of diabetic vasculopathy

Advanced glycation endproducts (AGEs)-induced vascular smooth muscle cell (VSMCs) proliferation and formation of reactive oxygen species (ROS) are emerging as one of the important mechanisms of diabetic vasculopathy but little is known about the antioxidative action of HMG CoA reductase inhibitor (statin) on AGEs. We hypothesized that statin might reduce AGEs-induced intracellular ROS of VSMCs and analyzed the possible mechanism of action of statin in AGEs-induced cellular signaling. Aortic smooth muscle cell of Sprague-Dawley rat (RASMC) culture was done using the different levels of AGEs stimulation in the presence or absence of statin. The proliferation of RASMC, ROS formation and cellular signaling was evaluated and neointimal formation after balloon injury in diabetic rats was analyzed. Increasing concentration of AGEs stimulation was associated with increased RASMC proliferation and increased ROS formation and they were decreased with statin in a dose-dependent manner. Increased NF-κB p65, phosphorylated ERK, phosphorylated p38 MAPK, cyclooxygenase-2, and c-jun by AGEs stimulation were noted and their expression was inhibited by statin. Neointimal formation after balloon injury was much thicker in diabetic rats than the sham-treated group but less neointimal growth was observed in those treated with statin after balloon injury. Increased ROS formation, subsequent activation of MAPK system and increased VSMC proliferation may be possible mechanisms of diabetic vasculopathy induced by AGEs and statin may play a key role in the treatment of AGEs-induced diabetic atherosclerosis.     

Relaxin: new functions for an old peptide

The peptide relaxin (RLX) was one of the first hormones to be described with a specific function in parturition. In the past ten years, there has been a revaluation of RLX physiology and the concept that sex hormones play roles that are limited to reproductive functions is rapidly changing. In this view, growing evidence indicates that the peptide hormone RLX, structurally related to insulin and insulin-like growth factor and primarily secreted by the corpus luteum during pregnancy, besides well demonstrated actions on reproductive tissues, is involved in a variety of functions. Among them, RLX influences the brain and regulates pituitary hormone secretion, causes renal vasodilatation, increases coronary flow, exerts chronotropic action on the heart and affects gastrointestinal motor responses. Recent studies suggest that in several smooth muscles the hormone appears to act by promoting the biosynthesis of nitric oxide (NO), whose altered production may be involved in smooth muscle dysmotilities. The recent cloning of the RLX receptors and studies on their possible signal transduction mechanisms are stimulating researchers to further investigate the effects of this hormone and its mechanism of action. This may lead to the discovery of agonists and antagonists for RLX and the development of new therapeutic approaches in some human diseases. The aim of this mini-review is to summarize the most recent findings on the multiple actions of RLX hoping to bring a contribution for the future perspectives in this field.     

Intermediate complex of ATP hydrolysis and synthesis by muscle proteins.

Myosin catalyzed exchange between 32Pi and ATP in reaction medium during its enzymatic hydrolysis of ATP only by a very small amount. Addition of actin increased to a great extent the rate of incorporation of 32Pi in the presence of Mg. Glycerinated smooth muscle fibers also exhibited the ability to exchange 32Pi and ATP upon the application of external force (repeated stretching and releasing). A schematic mechanism of the action of actin and external force on acceleration of 32Pi incorporation is proposed and the importance of the M-ADP complex for force generation is suggested.     

Synthesis and contractile activity of substituted 1,2,3,4-tetrahydroisoquinolines

A series of different 1-monosubstituted and 1,1-disubstituted 1,2,3,4-tetrahydro-isoquinolines was synthesized in high yields from different ketoamides. We have developed a convenient method for the synthesis of disubstituted derivatives by interaction of ketoamides with organomagnesium compounds, followed by cyclization in the presence of catalytic amounts of p-toluenesulfonic acid (PTSA). A number of substituents at the C-1 in the isoquinoline skeleton were introduced varying either carboxylic acid or organomagnesium compound. Some of the obtained 1,1-dialkyl-1,2,3,4-tetrahydro-isoquinolines possess contractile activity against guinea pig's gastric smooth muscle preparations.     

复方黄芩滴鼻液的制备与临床应用

复方黄芩滴鼻液对过敏性鼻炎有确切疗效，通过对２７例过敏性鼻炎患者观察，２０例有效，５例好转，且无毒副作用，药效高，安全可靠，又因含有人体必需的微量元素及维生素等，而增加了机体的免疫力，使治愈效果增加。