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1.
Simultaneous Determination of Six Compounds in Rat Plasma by Ultra‑Performance Liquid Chromatography with Tandem Mass Spectrometry: Application in the Pharmacokinetic Study of Qing Gan‑Shu Yu‑Fang
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Hai Jiang A‑Jiao Hou Yan‑Yan Zhang Wen‑Jing Man Liu Yang Yong‑Hai Meng Xin‑Yue Guo Song Wang Jia‑Xu Zhang Bing‑You Yang Qiu‑Hong Wang Kelvin Chan Hai‑Xue Kuang 《World Journal of Traditional Chinese Medicine》2019,(4)
A rapid and high selective ultra?performance liquid chromatography (UPLC) with tandem mass spectrometry method for simultaneous
determination of six compounds including albiflorin, paeoniflorin, picroside I, picroside II, saikosaponin A, and saikosaponin D in rat plasma
was developed and validated using butyl p-hydroxybenzoate as an internal standard. One-step direct protein precipitation with acetonitrile was
used to extract the compounds from the rat plasma samples. Chromatographic separation was achieved using an ACQUITY UPLC BEH C18
column (100 mm × 2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min, using gradient mode containing 0.1% formic acid in water and acetonitrile
were used as the Mobile phase A and B. Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify
and quantify active components. Calibration curves showed good linearity (R2 > 0.9908) over a wide concentration range for all compounds.
The intra- and interday precision (relative standard deviation) ranged 2.4%–7.0% and 2.6%–8.0%, respectively. The accuracy (relative error)
was from ?13.0% to 13.2% at all quality control levels. The recovery ranged from 81.1% to 92.5%. The validated method was successfully
applied to pharmacokinetic study in rats after oral administration of Qing Gan?Shu Yu?Fang. The results show that one can draw a conclusion
that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo. 相似文献
2.
Identification of differentially expressed genes in omental adipose tissues of obese patients by suppression subtractive hybridization 总被引:1,自引:0,他引:1
Qiu J. Ni Y. H. Gong H. X. Fei L. Pan X. Q. Guo M. Chen R. H. Guo X. R. 《南京医科大学学报(自然科学版)》2007,27(5):427-427
To identify differentially expressed genes between obese individuals and normal control, we have undertaken suppression subtractive hybridization (SSH). Omental adipose tissues were obtained via abdominal surgery for appendicitis in both 13 obese subjects[BMI (body mass index) 〉 30 kg/m(2)] and 13 normal subjects (BMI 〉 18 and 〈 25 kg/m(2)). 相似文献
3.
Qiu Ming-cai邱明才 Li Song-lingand Bai Cheng-jiang白成江李松岭 Zhang Nai-xin张乃鑫Department of Endocrinology the First AffiliatedHospital Tianjin Medical College Tianjin 《中华医学杂志(英文版)》1987,100(4):330-332
Histomorphometric study was made on a series
of sections of undecalcified epiphyseal femoral
specimens from rats with experimental fluorosis. The
results revealed osteosclerosis in Group A (5 ppm)
being more severe than that in Group B (25 ppm)
With the increase of fluoride dose, the parameters
fell down instead of increased in parallel. There is
seemingly a threshold over which osteosclerosis in
fluorosis becomes less severe. In contrast to Bely's
conclusion the authors proposed that, fluoride toxi-
city, besides decreasing the number of osteoblasts,
may also activate the osteoblasts. The number of
osteoblasts may be increased with relative lower
dose of fluoride also. The net outcome is the in
crement in bone volume. When toxic dose of
fluoride is higher enough (higher than the proposed
threshold), however, the number of osteoblasts and
its activity are inhibited. So are the osteocytes. This
interpretation may be the cytological basis for
osteosclerosis in the experimental fluorosis. 相似文献
4.
乳腺癌和卵巢癌中BRCA基因的突变 总被引:2,自引:0,他引:2
一、BRCA1和BRCA2基因1990年Hall等[1] 发现家族性乳腺癌与 17号染色体长臂上的一个位点有关。随后Narod等[2 ] 也报道了家族性乳腺癌及卵巢癌与 17号染色体有关。 1994年这一基因位点被克隆鉴定 ,命名为BRCA1[3] 。该基因位于染色体 17q2 1,全长10 0kb ,含 2 4个外显子。蛋白产物的相对分子质量为 2 0 00 0 0 ,含 1863个氨基酸。它可能涉及细胞周期的调控以及DNA的修复。在培养细胞中 ,从G1期到S期的细胞中 ,BRCA1的表达增加。研究还显示BRCA1在快速增生的细胞中表达最高。缺乏BRCA1活性将使DN… 相似文献
5.
6.
肝素酶和碱性成纤维细胞生长因子与非小细胞肺癌转移和预后的关系 总被引:6,自引:0,他引:6
目的 探讨肝素酶(heparanase)和碱性成纤维细胞生长因子(bFGF)在人非小细胞肺癌(NSCLC)组织中表达的临床意义及其与肺癌转移和预后的关系。方法 采用免疫组织化学、原位杂交和Western blot方法,检测115例人NSCLC石蜡切片和45例新鲜肺癌及对应癌旁正常组织中肝素酶和bFGF的表达情况。采用χ^2检验、t检验、生存曲线和Cox比例风险回归等方法分析肝素酶和bFGF分别表达及共表达的意义。结果 免疫组织化学染色证实肝素酶(91/115)和bFGF(89/115)主要表达在癌细胞质和(或)细胞膜中,在正常肺泡上皮和支气管上皮中则呈阴性表达。Western blot也证实肝素酶在肺癌中的表达明显增高(P=0.041)。统计分析结果显示:肝素酶和bFGF的表达具有明显的一致性(P:0.0001),二者单独表达和共表达均与肺癌的分期、血管侵袭、淋巴结转移、微血管密度和预后有关,其中,二者共表达时与分期和微血管密度的相关性更显著;另外,bFGF还与肺癌的分化程度有关。多因素分析结果显示,肺癌的分化程度、血管浸润、淋巴结转移和bFGF的表达可以作为判断肺癌预后的危险因素,但肝素酶不是影响预后的独立因素。结论 肝素酶和bFGF均与肺癌的转移、血管生成和预后密切相关。 相似文献
7.
Building a mouse model hallmarking the congenital human cytomegalovirus infection in central nervous system 总被引:6,自引:0,他引:6
Tang JL Wang ML Qiu JJ Wu D Hu W Shi BF Hu Y Li JP Tang J Wang M Qiu J Shi B Li J 《Archives of virology》2002,147(6):1189-1195
To investigate the mechanisms that human cytomegalovirus (HCMV) can vertically transmit from the placenta of mice to infect their offspring in the central nervous system (CNS) and cause congenital anomalies, and in order to provide basic research for preparing HCMV vaccine, we have developed a new type of mouse model of HCMV congenital CNS infection. Pure strain mice were propagated after being infected with HCMV. Then the degree of infection by HCMV to offspring was determined. The experiment shows that in the infection groups the mortality of fetal mice and the fatality of neonatal mice in one week are higher than that of the control groups (P < or = 0.05). At the same time we investigated the CNS of fetus's mice whose mothers were infected by HCMV. Our results showed: 1. The virus was successfully isolated from their cerebral cortex. 2. The signal of HCMV hybridization print was found in their nervous cell through in situ hybridization. 3. Especially human herpes virus-like particles and inclusion bodies in the plasm of nerve cell were found in the tissue of their brain under the electron microscope. This new type of mouse model of HCMV inherent CNS infection will help prepare HCMV vaccine and research HCMV congenital infection in CNS. 相似文献
8.
Yu G Boone T Delaney J Hawkins N Kelley M Ramakrishnan M McCabe S Qiu WR Kornuc M Xia XZ Guo J Stolina M Boyle WJ Sarosi I Hsu H Senaldi G Theill LE 《Nature immunology》2000,1(3):252-256
We report that the tumor neurosis factor homolog APRIL (a proliferation-inducing ligand) stimulates in vitro proliferation of primary B and T cells and increases spleen weight due to accumulation of B cells in vivo. APRIL functions via binding to BCMA (B cell maturation antigen) and TACI (transmembrane activator and CAML-interactor) and competes with TALL-I (also called BLyS or BAFF) for receptor binding. Soluble BCMA and TACI specifically prevent binding of APRIL and block APRIL-stimulated proliferation of primary B cells. BCMA-Fc also inhibits production of antibodies against keyhole limpet hemocyanin and Pneumovax in mice, indicating that APRIL and/or TALL-I signaling via BCMA and/or TACI are required for generation of humoral immunity. Thus, APRIL-TALL-I and BCMA-TACI form a two ligands-two receptors pathway involved in stimulation of B and T cell function. 相似文献
9.
Hormones increase mRNA of cyclic-nucleotide-gated cation channels in airway epithelia 总被引:1,自引:0,他引:1
Qiu W Laheri A Leung S Guggino SE 《Pflügers Archiv : European journal of physiology》2000,441(1):69-77
Previous studies have shown that the mRNA of cyclic-nucleotide-gated nonselective cation (CNG) channels is expressed in rat airway epithelia and that these channels contribute to sodium-mediated short-circuit currents in cultured rat tracheal epithelia. Patch-clamp studies from human A549 cells indicate that these channels contribute to cGMP-stimulated L-cis-diltiazem- and dichlorobenzamil-inhibited whole-cell sodium currents. This study demonstrates that mRNA for primary and secondary subunits of CNG channels, halphaCNG1 and hbetaCNG1 respectively, are expressed in several human airway cell lines, including normal and cystic fibrosis bronchial airway cells, in normal and cystic fibrosis tracheal airway cell lines and nasal polyp tissue from a cystic fibrosis patient. The mRNA of ralphaCNG1 in rat lung increased in response to increased circulating glucocorticoids and decreased in animals with lowered circulating glucocorticoids after aminoglutethimide treatment. Likewise the mRNA of halphaCNG1 increased in the presence of glucocorticoids in cultured alveolar airway cells. The mRNA of alphaCNG1 in rat lung was also increased in response to a low-salt diet and lowered in animals fed a high-salt diet. Likewise the mRNA of alphaCNG1 was increased in response to increased aldosterone and decreased in animals given spironolactone. These results suggest that mRNA for alphaCNG1 increases in response to elevated glucocorticoids or mineralocorticoids. Because alphaCNG1 is a functional sodium entry channel in both rat and human airway epithelial cells, if channel protein is also elevated this channel could mediate an increase in sodium absorption across lung epithelia in response to circulating hormones. 相似文献
10.
We investigated effects of sleep on pain-related somatosensory evoked potentials (SEP) following painful electrical stimulation of the left index finger. The biggest advantage of this method is that signals ascending through both A-beta fibers relating to touch and A-delta fibers relating to pain can be recorded simultaneously. While the subject was awake, non-painful stimulation evoked early- and middle latency components, N20, P30 and N60, at the C4 electrode, and painful stimulation evoked not only early- and middle latency components at the C4 but also later pain-specific components, N130 and P240, at the Cz electrode. During sleep, N20 and P30 did not show a significant change in amplitude, N60 showed a slight but significant amplitude reduction, and N130 and P240 significantly decreased in amplitude or disappeared, as compared with those while awake. Therefore, we speculate on the mechanisms generating each component as follows; (1) N20 and P30 are the primary components generated in SI ascending through A-beta fibers. (2) N60 is the secondary component generated in SI involving cognitive function to some degree. (3) N130-P240 are the pain-specific components ascending through A-delta fibers, and closely related to cognitive function, because they were much affected by consciousness, different from the components ascending through A-beta fibers. 相似文献