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441.
Nam Jin Kim Sei-Ryang Oh Hyung Kyu Lee Hye Suk Lee 《Journal of pharmaceutical and biomedical analysis》2009
A purified extract isolated from the dried flower buds of Magnolia fargesii (NDC-052) is currently being evaluated for phase III clinical trials as a new anti-asthma drug. A rapid, sensitive and selective liquid chromatography–tandem mass spectrometric (LC/MS/MS) method for the simultaneous determination of magnolin and epimagnolin A, the major bioactive components of NDC-052, in rat plasma was developed. After liquid–liquid extraction with tolterodine as an internal standard, magnolin and epimagnolin A were separated on a Luna phenyl-hexyl column with the mobile phase of 70% methanol in 10 mM ammonium formate. The analytes were detected by an electrospray ionization tandem mass spectrometry in the multiple-reaction-monitoring mode. The standard curves were linear over the concentration range of 50–2500 ng/mL for magnolin and epimagnolin A in rat plasma. The intra- and inter-day coefficients of variation and relative errors for magnolin and epimagnolin A at four QC concentrations were 1.5–11.4% and 5.9–12.5%, respectively. The lower limits of quantification for magnolin and epimagnolin A were 50.0 ng/mL using 50 μL of plasma. This method was successfully applied to the pharmacokinetic study of magnolin and epimagnolin A after an oral administration of NDC-052 in male Sprague–Dawley rats. 相似文献
442.
D.M. Jiménez-AguilarA.E. Ortega-Regules J.D. Lozada-Ramírez M.C.I. Pérez-PérezE.J. Vernon-Carter J. Welti-Chanes 《Journal of food composition and analysis》2011,24(6):889-894
Blueberry is an important source of anthocyanins, which are highly colored substances recognized for their antioxidant activity. One of the drawbacks of using anthocyanins as food colorant is their low stability. The objective of this study was to evaluate the variations found in color and concentration of the compounds (which produce the color) on spray-dried powders, obtained from blueberry extracts with added mesquite gum. Ethanolic blueberry extracts were concentrated until reaching 35% of soluble solids. They were then spray-dried using mesquite gum as an encapsulating agent at 140 and 160 °C of air inlet temperature and 8.5, 9.1 and 9.6 mL/min of feeding rates. The lowest losses in the content of total phenolics, total anthocyanins, and color of the samples were found in samples dried at 140 °C and 9.1 mL/min. The microencapsulates that were stored for 4 weeks at 4 °C in the absence of light presented low degradation of phenolics (10%), anthocyanins (7%) and antioxidant activity (15%). Final color values were L = 39.87, C = 47.83 and H° = 28.59, with a total color difference ΔE = 5. 相似文献
443.
目的考察附子干姜不同比例配伍前后对急性心衰大鼠神经激素释放的影响。方法建立戊巴比妥钠致大鼠急性心衰动物模型,用ELISA法测定急性心衰大鼠血浆氨基末端脑钠肽原(NT-pro BNP)、心钠素(ANP)、肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)、醛固酮(ALD)含量。结果附子干姜配伍后均可降低急性心衰大鼠血浆NT-pro BNP、心钠素(ANP)、肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)、醛固酮(ALD)的含量,其中附子干姜配伍后作用明显优于附子组,尤以附子干姜1∶1组作用最强。结论附子干姜配伍能够调控急性心衰大鼠部分神经激素的释放,从而延缓急性心衰的发展。 相似文献
444.
445.
Joakim
verb Asma Aziz K. Zaman Cathinka Halle Julin Firdausi Qadri Kathrine Stene-Johansen Rajib Biswas Shaumik Islam Taufiqur Rahman Bhuiyan Warda Haque Synne Sandbu Jennifer L Dembinski Susanne Dudman 《Viruses》2022,14(11)
Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide. In many low-income countries it causes large outbreaks and disproportionally affects pregnant women and their offspring. Surveillance studies to find effective preventive interventions are needed but are hampered by the lack of funding and infrastructure. Dried blood spots (DBS) offer an easier and more robust way to collect, transport, and store blood samples compared to plasma/serum samples, and could ease some of the barriers for such studies. In this study we optimize an HEV IgG ELISA for DBS samples and validate it on 300 paired DBS and plasma samples collected in rural areas of Bangladesh from participants in a HEV vaccine study. We demonstrate that HEV IgG in blood stored as DBS is stable for two months at up to 40 °C, and for five freeze-thaw cycles. The specificity was 97% and the overall sensitivity of the DBS assay was 81%. The sensitivity was higher in samples from vaccinated participants (100%) compared to previously infected participants (59%), reflecting a positive correlation between IgG titer and sensitivity. We found a strong correlation between DBS and plasma samples with an r2 of 0.90, but with a higher degree of difference between individual paired samples. Our study shows that DBS offers a stable alternative to plasma/serum for HEV IgG measurements and can facilitate serological studies, particularly in resource limited areas. 相似文献
446.
目的 对广西壮、瑶医常用药物豆科植物水罗伞Fordia cauliflora根的活性成分进行研究。方法 采用反复硅胶柱色谱及薄层色谱进行分离纯化,通过理化方法及光谱分析鉴定其结构。结果 又分离出3个结晶性成分,经鉴定分别为2-[3-甲氧基苯基]-4H-呋喃[2,3-h]-1-苯并吡喃-4-酮(Ⅲ)、3-甲氧基-2-[3-羟基苯基]-4H-呋喃[2,3-h]-1-苯并吡喃-4-酮(Ⅳ)和水黄皮亭(水黄皮根素,pinnatin,V)。结论 化合物Ⅲ~Ⅳ均为首次从该植物中分离得到,其中Ⅲ,Ⅳ为新化合物,分别命名为水罗伞甲(cauliflorinA)和水罗伞乙素(cauliforin B)。 相似文献
447.
448.
掌叶大黄规范化种植技术及其主要病虫害防治 总被引:1,自引:0,他引:1
目的:规范掌叶大黄种植技术、提高掌叶大黄质量。方法:在多年研究和田间试验的基础上,总结规范了掌叶大黄种植技术和主要病虫害防治方法。结果:制订了掌叶大黄规范化种植的操作技术规程,初步确定了掌叶大黄主要病虫害防治的方法。结论:规范掌叶大黄种植技术和主要病虫害防治方法,对提高掌叶大黄质量与产量具有重要作用。 相似文献
449.
Francesco Loria Estelle Maret Céline Schobinger Tiia Kuuranne Silke Grabherr Nicolas Leuenberger 《Drug testing and analysis》2023,15(4):444-448
Iron supplementation is not considered as a doping method; however, it can affect the levels of several biomarkers of the hematologic module of the athlete biological passport (ABP), such as the reticulocyte percentage (%RET) and hemoglobin (HGB) level. Thus, iron injection could be a confounding factor in antidoping analyses. Previous studies have suggested that the HGB level and the expression levels of reticulocyte-related-mRNAs, such as 5′-aminolevulinate synthase 2 (ALAS2) and carbonic anhydrase 1 (CA1), could be promising biomarkers for the ABP and detectable in dried blood spots (DBSs). Therefore, in this study, we examined the impact of iron injection on the levels of these potential biomarkers in DBSs. Reticulocyte-related-mRNAs analyses were performed by RT-qPCR. Ferritin level in DBS was measured with enzyme-linked immunosorbent assay (ELISA) method. Notably, there were no significant effects of iron supplementation on the levels of ALAS2 and CA1 mRNAs but by contrast, the %RET and immature reticulocyte fraction (IRF) measured in whole blood increased significantly following iron injection. As expected, iron supplementation increased the ferritin level significantly in both serum and DBS samples. In conclusion, these findings reinforce the specificity of reticulocyte-related mRNAs in DBSs as biomarkers of blood doping to target in antidoping analyses. 相似文献
450.
Also in 2021/2022, considerable efforts were invested into advancing human sports drug testing programs, recognizing and taking into account existing as well as emerging challenges in anti-doping, especially with regard to substances and methods of doping specified in the World Anti-Doping Agency's 2022 Prohibited List. In this edition of the annual banned-substance review, literature on recent developments published between October 2021 and September 2022 is summarized and discussed. Focus is put particularly on enhanced analytical approaches and complementary testing options in human doping controls, appreciating the exigence and mission in anti-doping and, equally, the contemporary “new normal” considering, for example, the athlete's exposome versus analytical sensitivity and applicable anti-doping regulations for result interpretation and management. 相似文献