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51.
The first biomimetic conversion from the aconitine-type C19-diterpenoid alkaloids to the corresponding alkaloids of lactone-type C19-diterpenoid alkaloid has been achieved. Chasmanine was used as starting material with Baeyer–Villiger oxidation as a key reaction. It was also observed that the oxygenated group at C-16 did not change the relative migration tendencies of C-13 and C-9 during the oxidation. Meantime, a novel D-ring fragmented compound was obtained during the course of the present investigation. The plausible mechanism of the formation of this compound was also proposed. 相似文献
52.
高效液相色谱法测定风湿骨痛丸中双酯型生物碱的限度 总被引:1,自引:0,他引:1
目的建立高效液相色谱法测定风湿骨痛丸中双酯型生物碱的限度。方法供试品采用超声处理法,双酯型生物碱中三种成分通过菲罗门C18被检测,柱温30℃,以乙腈—四氢呋喃—0.1 mol.L-1的乙酸铵溶液(每1 000 mL中加冰醋酸0.5 mL)(12.5∶7.5∶80)为流动相,检测波长230 nm。结果乌头碱、次乌头碱、新乌头碱峰分离度均良好,且无干扰。结论此法准确,重复性好,可用于控制该处方中制川乌、制草乌中双酯型生物碱的限度。 相似文献
53.
《Expert review of clinical pharmacology》2013,6(4):377-381
Acne is a chronic inflammatory disease for which a long-lasting therapy, very often with topical drugs, is necessary. Despite the fact that several topical antiacne drugs (in particular, tretinoin, benzoyl peroxide, clindamycin and erythromycin) are used for many years, often on broad skin surfaces and for long periods of time, their potential for contact sensitization is low. Their potential for phototoxic and photoallergic reactions is also low. Much more frequent is irritant contact dermatitis caused by some of these drugs, in particular, retinoids and benzoyl peroxide, for which the short contact therapy has been recently suggested. 相似文献
54.
Patrícia Pozzatti Gustavo O. dos Reis Danielle F. Pereira Heros Horst Leandro Espindola Melina Heller Gustavo A. Micke Moacir G. Pizzolatti Tânia S. Fröde 《Pharmacological reports : PR》2013,65(5):1263-1271
BackgroundDihydrocorynantheol (DHC) is an alkaloid compound isolated from Esenbeckia leiocarpa Engl. that has demonstrated anti-inflammatory properties in experimental models. The aim of this study was to investigate whether the modification of the chemical structure of DHC could alter its anti-inflammatory effect in a mouse model of pleurisy induced by carrageenan.MethodsDHC was isolated from Esenbeckia leiocarpa Engl. Capillary electrophoresis, physical characteristics, spectral data produced by infrared analysis and nuclearmagnetic resonance (1H and 13C), andmass spectrometry analysiswere used to identify and elucidate DHC structure. The DHC compound was subjected to chemical structural modifications by nucleophilic substitution reactions, yielding five analogous compounds: acetyl (1), p-methylbenzoyl (2), benzoyl (3), p-methoxybenzoyl (4) and p-chlorobenzoyl (5). Swiss mice were used throughout the experiments. Pro-inflammatory parameters leukocyte migration, exudate concentrations and myeloperoxidase (MPO) activity were quantified in the fluid leakage from the mouse pleural cavities at 4 h after pleurisy induction.ResultsDHC and its analogues acetyl, p-methylbenzoyl, benzoyl, p-methoxybenzoyl and p-chlorobenzoyl inhibited total and differential leukocyte migration andMPOactivity (p < 0.05). OnlyDHCsignificantly decreased the exudate concentrations (p < 0.01).ConclusionsDHC was more effective than its analogues as an anti-inflammatory agent in the mouse model of pleurisy induced by carrageenan.We did not determine what physicochemical modifications altered the anti-inflammatory effect of DHC, but this effect may be due to the modifications on the hydroxyl group at carbon 17 of the DHC. 相似文献
55.
目的:建立消炎止痛膏的新质量标准。方法:采用薄层色谱(TLC)法对方中大黄、黄柏、半夏进行定性鉴别以及对制草乌含乌头碱进行限量测定;用高效液相色谱(HPLC)对制马钱子中的马钱子碱和士的宁进行含量测定。结果:TLC斑点清晰,分离度好;马钱子碱和士的宁进样量都在0.20~2.0μg之间与峰面积积分值呈良好的线性关系(r=1.000),马钱子碱的平均回收率为97.8%,RSD为0.86%(n=6);士的宁的平均回收率为96.6%,RSD为1.20%(n=6)。结论:所建立的标准适用于院内制剂消炎止痛膏的质量控制。 相似文献
56.
中药提取物配伍对乳腺癌MDA-MB-231BO细胞侵袭作用的影响及其机制 总被引:1,自引:0,他引:1
目的:探讨中药蛇床子、补骨脂、附子有效成分蛇床子素、补骨脂素、乌头碱对乳腺癌细胞株MDA-MB-231BO的侵袭抑制作用及其机制。方法:采用均匀设计实验方案进行组方设计,逐步回归分析拟合蛇床子素、补骨脂素配伍乌头碱的回归方程;采用人乳腺癌骨高转移细胞(MDA-MB-231BO)体外侵袭实验,实时荧光定量聚合酶链反应检测,观察药物处理MDA-MB-231BO细胞后,细胞侵袭作用特点和相关基因的表达。结果:通过逐步回归方程,获取蛇床子素、补骨脂素和乌头碱3个药物的最佳配伍比例为6.44∶8.89∶9.44;有效成分和阳性药物唑来磷酸注射液在体外作用24h可以显著抑制MDA-MB-231BO细胞的侵袭;药物处理组转化生长因子β1(transforming growth factor-β1,TGF-β1)、Smad2、Smad3、Smad4、Smad7、核因子κB(nuclear factor-κB,NF-κB)、NF-κB受体活化因子(receptor activator of NF-κBligand,RANK)mRNA表达量显著降低,最佳药物配伍组和唑来磷酸药物组与空白对照组,最佳药物配伍组与最差药物配伍相比差异有统计学意义(P〈0.01)。结论:蛇床子素、补骨脂素、乌头碱配伍应用可显著抑制MDA-MB-231BO细胞侵袭,其机制与抑制TGF-β/Smad的信号转导有关,同时可降低NF-κB和RANK的表达。 相似文献
57.
目的:总结乌头碱中毒的临床特征和治疗方法,以提高其抢救成功率.方法:回顾性分析我科2010年1月~2011年12月收治的13例乌头碱中毒患者的临床资料.结果:13例均出现心律失常,其中室性早搏10例,频发多源性室早8例,反复室速、室颤3例,窦性心动过缓、房室传导阻滞2例;治愈12例,死亡1例.结论:尽快清除体内毒物、及早血液灌流、积极有效控制各类心律失常等综合治疗是提高乌头碱中毒抢救成功率的关键. 相似文献
58.
Azhipa O Kimizuka K Nakao A Toyokawa H Okuda T Neto JS Alber SM Kaizu T Thomson AW Demetris AJ Murase N 《Clinical immunology (Orlando, Fla.)》2005,114(2):199-209
We have shown that tacrolimus (TAC)-induced liver allograft acceptance is associated with migration and persistence of donor B cells and dendritic cells (DC). To clarify whether these MHC class II+ leukocytes have favorable roles in inducing tolerance, we analyzed recipient T cell reactions after allogeneic B or DC infusion. LEW rat B cells localized exclusively in BN host B cell follicles without any direct contact with host T cells. While few donor DC migrated to T cell areas and marginal zones, they were captured by host APC, suggesting that allogeneic MHC class II+ cells may induce immune reactions via the indirect pathway. Although DC-infused non-immunosuppressed recipients showed enhanced ex vivo anti-donor responses, persistent in vitro donor-specific hyporeactivity was seen equally with donor DC or B cell infusion under TAC. The results indicate that donor MHC class II+ APC are capable of regulating recipient immune reactions under TAC. Possible involvement of the indirect pathway of allorecognition is discussed. 相似文献
59.
目的:优化大孔吸附树脂回收制川乌炮制有毒废水中6种生物碱类成分的工艺条件,为其他药物炮制废水的处理提供参考。方法:以苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头原碱、新乌头碱、次乌头碱和乌头碱的吸附率和洗脱率为考察指标,利用静态吸附-洗脱试验对15种大孔吸附树脂进行筛选,并通过与动态吸附相结合的方法,优选大孔树脂的回收工艺参数。结果:D101型大孔树脂对制川乌炮制废水中6种生物碱类成分具有较好的吸附和洗脱效果,最佳工艺参数为每克大孔树脂可处理4. 3 g川乌的炮制废水,上样速度≤3. 0 m L·min-1为宜,水洗除杂用量2 BV,加70%乙醇6 BV洗脱。苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头原碱新、新乌头碱、次乌头碱、乌头碱的回收率依次为98. 03%,94. 09%,96. 53%,78. 15%,85. 40%,70. 57%。结论:D101型大孔树脂在进行制川乌炮制废水减毒处理的同时,还可对其所含的6种生物碱类成分进行有效回收,在解决环保问题的同时,创造了一定的经济效益,且优选的工艺条件稳定可行。 相似文献
60.
目的 :测定保心提取液中乌头类生物碱的含量。方法 :采用离子对萃取—分光光度法测定 ,并对标准曲线制备、加样回收率试验、精密度试验、专属性试验、耐用性试验等项目进行了方法学考察。结果 :测定方法线性关系良好 ,平均回收率 99.4 % ,并具有良好的精密度、专属性和耐用性。结论 :该法用于测定保心提取液中乌头类生物碱的含量准确可靠、简便易行、专属性强 相似文献