/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/
/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/
来源:Hazardous Substances Data Bank (HSDB)
毒理性
解毒与急救
/SRP:/ 高级治疗:对于无意识、严重肺水肿或严重呼吸困难的病人,考虑进行口咽或鼻咽气管插管以控制气道。使用气囊面罩装置的正压通气技术可能有益。考虑使用药物治疗肺水肿……。对于严重的支气管痉挛,考虑给予β激动剂,如沙丁胺醇……。监测心率和必要时治疗心律失常……。开始静脉输注D5W /SRP: "保持开放",最低流量/。如果出现低血容量的迹象,使用0.9%生理盐水(NS)或乳酸林格氏液。对于伴有低血容量迹象的低血压,谨慎给予液体。注意液体过载的迹象……。使用地西泮或劳拉西泮治疗癫痫……。使用丙美卡因氢氯化物协助眼部冲洗……。 /Poisons A and B/
/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/
/ALTERNATIVE and IN VITRO TESTS/ Pseudolaric acid B (PAB), the naturally occurring diterpenoid isolated from the root bark of Pseudolarix kaempferi Gordon tree (Pinaceae), possesses potent antifungal and pregnancy-terminating effects that may be tightly associated with angiogenesis. This study was to examine its angiogenic inhibition, impact on vascular endothelial growth factor (VEGF) secretion from tumor cells and the possible mechanism of action. Angiogenesis inhibition was assessed by the human umbilical vascular endothelial cell proliferation, migration, and tube-formation assays, as well as the chorioallantoic membrane assay. ELISA, reverse transcription-PCR, and Western blotting analyses were performed to examine VEGF protein secretion, mRNA expression, and the possible mechanism in hypoxic MDA-MB-468 cells. PAB displayed potent in vitro antiangiogenic activity shown by inhibiting VEGF-stimulated proliferation and migration and fetal bovine serum-stimulated tube formation of human umbilical vascular endothelial cells in a concentration-dependent manner. Moreover, PAB (10 nmol per egg) significantly suppressed in vivo angiogenesis in the chorioallantoic membrane assay. On the other hand, PAB abrogated hypoxia-induced VEGF secretion from MDA-MB-468 cells via reducing HIF-1alpha protein. Additional analyses using LY294002 and U0126 indicated that the increase in hypoxia-inducible factor 1 (HIF-1)alpha protein level was highly dependent on phosphatidylinositol 3'-kinase and p42/p44 mitogen-activated protein kinase activities in hypoxic MDA-MB-468 cells. However, PAB treatment did not affect the active (phosphorylated) forms of Akt and Erk. Interestingly, the selective proteasome inhibitor MG-132 completely reversed the reduction of HIF-1alpha protein in the PAB-treated MDA-MB-468 cells. PAB displays the dual antiangiogenic activities of directly inhibiting endothelial cells and abrogating paracrine stimulation of VEGF from tumor cells due to reducing HIF-1alpha protein by promoting its proteasome-mediated degradation in MDA-MB-468 cells, which has potential clinical relevance.
来源:Hazardous Substances Data Bank (HSDB)
毒理性
人类毒性摘录
本研究旨在探讨伪麻黄酸B(PAB)对人乳腺癌MCF-7细胞的抑制作用。采用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐分析、形态学变化、橘黄橙染色和琼脂糖凝胶电泳来检测凋亡。通过乳酸脱氢酶活性基础的细胞毒性分析计算凋亡和坏死细胞的百分比;检测衰老相关(SA)-β-半乳糖苷酶活性以评估衰老;进行碘化丙啶染色的流式细胞术分析以调查细胞周期的分布,并通过 Western 印迹分析检查蛋白质表达。在凋亡过程中,半最大抑制浓度IC50在PAB处理36小时和48小时后分别为3.4和1.35微摩尔/升。暴露于PAB的MCF-7细胞显示出凋亡的典型特征,包括形态变化和DNA片段化。用4微摩尔/升PAB处理36小时的MCF-7细胞经历了凋亡,但没有坏死。PAB诱导的凋亡与死亡受体途径无关。衰老细胞变得更大且更扁平,SA-β-半乳糖苷酶染色呈阳性。PAB诱导明显的有丝分裂停滞,它先于凋亡和衰老。随着PAB处理,p21和p53的表达上调,cyclin B1上调并从细胞质转运到细胞核,并保持稳定水平。PAB诱导MCF-7细胞的有丝分裂停滞,并通过凋亡和衰老抑制增殖。凋亡与死亡受体途径无关。
/ALTERNATIVE and IN VITRO TESTS/ The aim of the present study was to investigate the inhibitory effect of pseudolaric acid B (PAB) on human breast cancer MCF-7 cells. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis, morphological changes, acridine orange staining, and agarose gel electrophoresis were applied to detect apoptosis. The percentage of apoptotic and necrotic cells was calculated by the lactate dehydrogenase activity-based cytotoxicity assay; senescence associated (SA)-beta-galactosidase activity was detected to evaluate senescence; flow cytometric analysis of propidium iodide staining was carried out to investigate the distribution of cell cycle, and the protein expression was examined by Western blot analysis. During apoptosis, the half maximal inhibitory concentration IC(50)was 3.4 and 1.35 umol/L at 36 and 48 hr after PAB treatment, respectively. The MCF-7 cells exposed to PAB showed typical characteristics of apoptosis, including the morphological changes and DNA fragmentation. The MCF-7 cells treated with 4 umol/L PAB for 36 hr underwent apoptosis, but not necrosis. The apoptosis induced by PAB was independent of the death receptor pathway. The senescent cells became larger and flatter, and the SA-beta-galactosidase staining was positive. PAB induced obvious mitotic arrest and it preceded apoptosis and senescence. The expressions of p21 and p53 was upregulated with PAB treatment, and cyclin B1 was upregulated and transported from the cytoplasm to nuclei, and sustained stable levels. PAB induced mitotic arrest in the MCF-7 cells and inhibited proliferation through apoptosis and senescence. The apoptosis was independent of the death receptor pathway.
A novel Pseudolaric acid B derivative, Hexahydropseudolaric acid B, exterts an immunomodulatory effect in vitro/in vivo evaluation
摘要:
Identification of immunosuppressants from natural sources has a proven track record in immune mediated disorders. Pseudolaric acid B is a diterpenoid isolated from the roots of Pseudolarix amabilis, possessing potent immunomodulatory effect. However, the cytotoxicity limits its future clinical application. The purpose of this study was to investigate the immunosuppressive activity of Hexahydropseudolaric acid B. a Pseudolaric acid B derivative, on T cell mediated immune response both in vitro and in vivo, and investigated its immunomodulatory effect to develop a more ascendant immunosuppressive agent. The results showed that Hexahydropseudolaric acid B could exert more preferable immunosuppressive activity and lower cytotoxicity than Pseudolaric acid B. Hexahydropseudolaric acid B significantly inhibited T cell proliferation activated by mitogen and alloantigen without obvious cytotoxicity in vitro. Furthermore, Hexahydropseudolaric acid B could ameliorate ear swelling in a mouse model of 2,4-dinitrofluorobenzene-induced delayed-type hypersensitivity in vivo. Mechanistic study revealed that Hexahydropseudolaric acid B could enhance regulatory T cells via promoting Foxp3 expression and TGF-beta level, accompanied by attenuating Akt activation, blocking p38MAPK/MK2-HSP27 signal cascades, and up-regulating PPAR-gamma expression. Taken together, these results suggest that Hexahydropseudolaric acid B exerts more preferable immunosuppressive activity than its precursor Pseudolaric acid B by affecting multiple targets, which support the need for continued efforts to characterize the efficacy of HPAB as a promising and safe candidate to treat immune-related diseases. (C) 2014 Elsevier B.V. All rights reserved.
Toward the total synthesis of pseudolaric acid B. Preparation of a key intermediate by degradation and its use in the reassembly of the natural product
作者:Baogen Wu、Jean M. Karle、E.Blake Watkins、Mitchell A. Avery
DOI:10.1016/s0040-4039(02)00596-8
日期:2002.5
Synthetic studies of pseudolaricacid B, 2, provided a relay synthesis of pseudolaricacid B (PLAB) via aldehyde 5. The aldehyde 5 can serve: to complete the totalsynthesis of PLAB; as a precursor for the synthesis of PLAB analogs; or as a substrate for the generation of radiolabeled PLAB for mechanistic studies.