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《Gaceta sanitaria / S.E.S.P.A.S》2021,35(4):399-401
Chile's October 2019 popular revolt has again made human rights violations visible in the context of mass mobilizations. In terms of damage to the population's health, multiple eye injuries produced by kinetic impact projectiles and tear bombs against people were reported, leading to an outbreak of unpublished eye injuries worldwide. There was excessive use of chemical weapons, and the totality of the chemicals used has not been transparent. The impact on mental health, especially of the population who lived during dictatorship in the 1970s, is uncertain and, health care was overwhelmed in the most vulnerable geographic areas. It is urgent to establish a timely and transparent system for monitoring such lesions and transparent all chemical compounds in tear-tearing and the composition of kinetic impact projectiles. 相似文献
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《Saudi Pharmaceutical Journal》2022,30(5):532-543
Folium Artemisiae argyi Carbonisatum (FAAC) is a traditional medicine widely used in clinic. It has the effect of hemostasis by warming meridians. In order to further explore the chemical composition and biological activity of FAAC, the methanol extract of FAAC was isolated and purified by open column and high- performance liquid chromatography. and the complete structure was characterized by nuclear magnetic resonance (NMR) and LREI-MS for the first time, namely rutin, quercetin and octacosanol respectively. Initially the toxic effect of methanol extract of FAAC on zebrafish was evaluated by observing the phenotypic characteristics, spontaneous twitch times, heart rate, hatching rate, the distance of SV-BA and cardiomyocyte apoptosis of zebrafish. The results showed that FAAC has embryonic development toxicity and cardiotoxicity when it was higher than 62.5 μg/mL. Meanwhile, the hemostatic effect of methanol extract of FAAC was compared with FAA (Folium Artemisia argyi) by zebrafish intestinal bleeding model originally. The results showed that the hemostatic effect of the medium and high concentration dose groups (3.0 and 30.0 μg/mL) was enhanced for both FAAC and FAA. This study provided an experimental basis for the clinical application of FAAC. 相似文献
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《中医科学杂志(英文)》2020,7(3):233-244
ObjectiveThe objective of this study was to verify the lipid-lowering effect of Juhe Fang extract (JHFE) and to determine its characteristic chemical profile in vitro and in vivo.MethodsA hyperlipidemia model was established by feeding mice a high-fat diet (HFD). After treatment for 30 days, serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were measured with an automatic biochemistry analyzer. The components from JHFE obtained from in vivo and in vitro experiments were investigated using an UPLC-Q Exactive-Orbitrap MS/MS.ResultsThe TC, TG, and LDL-C in the serum significantly decreased and the HDL-C significantly increased after JHFE treatment. A total of 95 compounds from JHEF including 15 phenolic acids (PA), 4 phenylethanoid glycosides (PG), 24 flavonoids (F), 14 triterpenoids (T), 10 diterpenoid glycosides (D), 18 alkaloids (A) and 10 others (O) were identified. Trigonelline was discovered for the first time in a herbal medicine of Juhe Fang. Furthermore, 68 compounds were identified in vivo including 28 prototype compounds and 40 metabolites. The metabolic characteristics of these components were revealed including identification of new metabolites of 4-hydroxyphenyl ethyl-8-O-[α-L- arabinopyranosyl-(1 → 6)]-β-D-glucopyranoside (PEG) and lirinidine. A total of 43 components from JHFE were absorbed and/or metabolized. The contribution rate of each type of chemical component from JHFE to its lipid-lowering effect from high to low were A, F, PG, PA, D and T.ConclusionThe results of this study showed that JHFE demonstrated a significant lipid-lowering effect in a high-fat diet (HFD)-induced hyperlipidemia mouse model. Specific types of PA, PG, F, D, T and A formed the pharmaceutical architecture of the lipid-lowering effect of JHFE. This study should prove useful for clarifying the components responsible for the lipid-lowering effect of JHFE and provide a basis for precision quality control research. 相似文献
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目的利用UPLC-LTQ-Orbitrap-MS技术对刺果番荔枝叶的化学成分进行定性分析。方法采用Waters Acquity UPLC HSS T 3色谱柱(2.1 mm×100 mm,1.8μm),流动相为0.1%甲酸水(A)和乙腈(B)梯度洗脱,流速为0.3 mL/min,进样量2μL,在电喷雾正负离子模式下采集数据。经Reaxys数据库检索番荔枝属类化合物信息,通过质谱信息比对各化合物的m/z值、保留时间、质谱特征碎片等,并结合文献数据对鉴定的化合物进行验证。结果根据各化合物的特征裂解规律,从刺果番荔枝叶中共鉴定出45个化合物,包括16个生物碱类,14个番荔枝内酯类,7个黄酮类和8个其他类化合物,其中以番荔枝内酯类和生物碱类成分居多,与文献报道番荔枝内酯与生物碱类化合物是发挥抗癌的主要活性成分一致。结论利用UPLC-LTQ-Orbitrap-MS技术对刺果番荔枝叶中的化学成分进行了快速、准确的定性分析,为刺果番荔枝叶的提取分离与药效物质基础的研究提供依据。 相似文献
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Imaging chemical exchange saturation transfer (CEST) effects following tumor‐selective acidification using lonidamine 下载免费PDF全文
Increased lactate production through glycolysis in aerobic conditions is a hallmark of cancer. Some anticancer drugs have been designed to exploit elevated glycolysis in cancer cells. For example, lonidamine (LND) inhibits lactate transport, leading to intracellular acidification in cancer cells. Chemical exchange saturation transfer (CEST) is a novel MRI contrast mechanism that is dependent on intracellular pH. Amine and amide concentration‐independent detection (AACID) and apparent amide proton transfer (APT*) represent two recently developed CEST contrast parameters that are sensitive to pH. The goal of this study was to compare the sensitivity of AACID and APT* for the detection of tumor‐selective acidification after LND injection. Using a 9.4‐T MRI scanner, CEST data were acquired in mice approximately 14 days after the implantation of 105 U87 human glioblastoma multiforme (GBM) cells in the brain, before and after the administration of LND (dose, 50 or 100 mg/kg). Significant dose‐dependent LND‐induced changes in the measured CEST parameters were detected in brain regions spatially correlated with implanted tumors. Importantly, no changes were observed in T1‐ and T2‐weighted images acquired before and after LND treatment. The AACID and APT* contrast measured before and after LND injection exhibited similar pH sensitivity. Interestingly, LND‐induced contrast maps showed increased heterogeneity compared with pre‐injection CEST maps. These results demonstrate that CEST contrast changes after the administration of LND could help to localize brain cancer and monitor tumor response to chemotherapy within 1 h of treatment. The LND CEST experiment uses an anticancer drug to induce a metabolic change detectable by endogenous MRI contrast, and therefore represents a unique cancer detection paradigm which differs from other current molecular imaging techniques that require the injection of an imaging contrast agent or tracer. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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安息香为安息香科白花树Styrax tonkinensis (Pierre) Craib ex Hart.的干燥树脂,主要化学成分为香脂酸类和三萜类物质,及少数木脂素类物质,其中香脂酸类化合物是其主要活性成分。安息香主要药理活性有抗炎解热、抗肿瘤、血脑屏障保护等。本文对安息香药材的化学成分和药理作用进行了综述,并从多角度分析预测了安息香可能的质量标志物,为安息香药材的质量控制、合理开发与利用提供参考。 相似文献