银杏二萜内酯葡胺注射液中银杏内酯A、B、K与人血浆蛋白结合率的测定

目的：研究银杏二萜内酯葡胺注射液与人血浆蛋白的结合情况。方法：采用平衡透析法测定银杏二萜内酯葡胺注射液中银杏内酯A（GA）、银杏内酯B（GB）和银杏内酯K（GK）与人血浆蛋白的结合 率,以LC-MS/MS法测定透析内外液中各待测物的浓度,计算其血浆蛋白结合率。结果：血浆中其他成分对测定无干扰,各待测物在选择浓度范围内线性关系均良好,精密度及稳定性结果均符合方法学要求;样品孵育8 h后,GA、GB和GK与人血浆蛋白结合基本达到平衡,此时GA（0.34、1.70 和8.51 μg·mL^-1）与人血浆蛋白结合率为84.03%-88.11%,GB（0.62、3.09 和15.5 μg·mL^-1）与人血浆蛋白结合率为41.21%-53.56%,GK（0.04、0.20 和1.01 μg·mL^-1）与人血浆蛋白结合率为45.24%-59.59%。结论：该方法操作简便、快速,灵敏度高,能满足生物样品的分析要求。GA与血浆蛋白结合较强,GB和GK具有中等强度的蛋白结合率。     

银杏内酯类化合物在大鼠体内的绝对生物利用度研究

研究银杏内酯A(GA)、银杏内酯B(GB)和白果内酯(BB)在大鼠体内的药动学特征及其绝对生物利用度。该实验建立了检测大鼠血浆中GA,GB,BB的LC-MS/MS分析方法,考察大鼠经口服(ig)和静脉注射(iv)给药后血浆中3种银杏内酯类化合物的血药浓度,采用DAS 2.0药动学处理软件,计算GA,GB,BB的药动学参数及其绝对生物利用度。结果显示,GA,GB,BB经大鼠注射给药后的C_max分别为(513.9±116.9),(701.3±76.0),(5 255.6±476.8) μg·L^-1,AUC_0-t分别为 (960.9±268.5),(779.5±140.6),(7 409.3±1 181.1) μg·h·L^-1;灌胃给药后的C_max分别为(522.9±39.9),(146.8±31.6), (2 711 .9±588.9) μg·L^-1,AUC_0-t分别为(1 760.4±300.7),(636.6±180.3),(16 651.4±1 306.5) μg·h·L^-1。GA,GB,BB在大鼠体内的的绝对生物利用度分别为(61.1±10.4)%,(27.2±7.7)%,(56.2±4.4)%。该实验所建立的方法专属性好,灵敏度高,可用于GA,GB,BB在大鼠体内的药代动力学和生物利用度研究。     

LC-MS/MS法同时测定消毒产品中6种抗生素残留

目的建立同时测定消毒产品中甲硝唑、盐酸金霉素、土霉素二水合物、盐酸米诺环素、红霉素及盐酸四环素的高效液相色谱-串联质谱(LC-MS/MS)检测方法。方法样品经甲醇超声提取,0.45μm聚四氟乙烯膜过滤后,选择WatersSymmetryC18(2.1mm×150mm,3.5μm)为分析柱,5mmol/L乙酸铵缓冲溶液、甲醇和乙腈为流动相,用LC-MS/MS正离子扫描多反应监测模式检测。结果上述6种抗生素在0～2000ng/ml范围内线性关系良好,相关系数均大于0.998,回收率为74.7%～114%,相对标准偏差为1.6%～20.2%。该法成功用于115件皮肤、黏膜使用的膏霜剂型抗(抑)菌制剂消毒产品中抗生素残留量的检测。结论该法操作简单,灵敏度高,选择性强,可用于膏霜剂型消毒产品中抗生素残留量的测定。     

Immunocompetent truncated E2 glycoprotein of bovine viral diarrhea virus (BVDV) expressed in Nicotiana tabacum plants: a candidate antigen for new generation of veterinary vaccines

The bovine viral diarrhea virus (BVDV) is the etiological agent responsible for a wide spectrum of clinical diseases in cattle. The glycoprotein E2 is the major envelope protein of this virus and the strongest inductor of the immune response. There are several available commercial vaccines against bovine viral diarrhea (BVD), which show irregular performances. Here, we report the use of tobacco plants as an alternative productive platform for the expression of the truncated version of E2 glycoprotein (tE2) from the BVDV. The tE2 sequence, lacking the transmembrane domain, was cloned into the pK7WG2 Agrobacterium binary vector. The construct also carried the 2S2 Arabidopsis thaliana signal for directing the protein into the plant secretory pathway, the Kozak sequence, an hexa-histidine tag to facilitate protein purification and the KDEL endoplasmic reticulum retention signal. The resulting plasmid (pK-2S2-tE2-His-KDEL) was introduced into Agrobacterium tumefaciens strain EHA101 by electroporation. The transformed A. tumefaciens was then used to express tE2 in leaves of Nicotiana tabacum plants. Western blot and ELISA using specific monoclonal antibodies confirmed the presence of the recombinant tE2 protein in plant extracts. An estimated amount of 20 μg of tE2 per gram of fresh leaves was regularly obtained with this plant system. Injection of guinea pigs with plant extracts containing 20 μg of rtE2 induced the production of BVDV specific antibodies at equal or higher levels than those induced by whole virus vaccines. This is the first report of the production of an immunocompetent tE2 in N. tabacum plants, having the advantage to be free of any eventual animal contaminant.     

液相色谱-串联质谱法测定奶粉和液态奶中三聚氰酸

目的:建立奶粉和液态奶中三聚氰酸的液相色谱-串联质谱检测方法(LC-MS/MS)。方法:样品加水混匀后加乙腈超声波提取,经固相萃取柱净化,采用亲水作用色谱柱分离,在电喷雾负电离多反应监测模式下进行定性和内标法定量。结果:本法线性范围为0μg/kg～500μg/kg,定量限为200μg/kg,3个添加水平的平均回收率在92.1%～104.3%,精密度(RSD%)为3.22%～7.61%。结论:该法简便、快速、准确,适于奶粉和液态奶中三聚氰酸的检测。     

ICP-MS测定橡胶产品浸泡水中锌的探讨

目的:建立电感耦合等离子体质谱法(ICP-MS)测定橡胶产品浸泡液中锌含量的方法。方法:橡胶产品浸泡液直接用ICP-MS进行测定,用内标法消除基体干扰。结果:本方法与分光光度法相比较,其结果差异无显著性(P>0.05);回收率在93.0%～99.5%之间,相对标准偏差2.59%。结论:可用ICP-MS测定橡胶产品浸泡液中的锌,方法准确﹑简便并且快速。     

Canalopatias cardíacas: o papel das mutações nos canais de sódio

Introduction and objectives

The importance of sodium channels for the normal electrical activity of the heart is emphasized by the fact that mutations (inherited or de novo) in genes that encode for these channels or their associated proteins cause arrhythmogenic syndromes such as the Brugada syndrome and the long QT syndrome (LQTS). The aim of this study is to conduct a review of the literature on the mutations in the sodium channel complex responsible for heart disease and the implications of a close relationship between genetics and the clinical aspects of the main cardiac channelopathies, namely at the level of diagnosis, risk stratification, prognosis, screening of family members and treatment.

Association between habitual coffee consumption and metabolic syndrome in type 1 diabetes

Background and aimsIn the general population, habitual coffee consumption is inversely associated with the metabolic syndrome, a syndrome that is rather common also in patients with type 1 diabetes. However, whether coffee intake is beneficially related to the metabolic syndrome also in type 1 diabetes, is not known. We, therefore, studied the potential association between coffee consumption and the metabolic syndrome in a large population of individuals with type 1 diabetes. Furthermore, we investigated whether coffee consumption is associated with insulin resistance (estimated glucose disposal rate, eGDR), kidney function (estimated glomerular filtration rate, eGFR), and low-grade chronic inflammation (high-sensitivity C-reactive protein, hsCRP).Methods and resultsData from 1040 participants in the Finnish Diabetic Nephropathy Study were included in these cross-sectional analyses. Metabolic syndrome was assumed if at least 3 of the following cardiovascular risk factors were present: central obesity, high blood pressure, low HDL-cholesterol concentration, high triglyceride concentration, and hyperglycaemia. Subjects were categorized based on self-reported daily coffee intake: non-consumers (<1 cup/d), low (≥1 cups/d < 3), moderate (≥3 cups/d < 5), and high coffee consumption (≥5 cups/d). In multivariable logistic regression analysis, moderate and high coffee consumption was associated with increased odds of the metabolic syndrome. Moreover, any level of coffee consumption was associated with increased risk of the blood pressure-component. An increasing trend was observed in the eGFR with increasing coffee consumption.ConclusionsIn type 1 diabetes, high coffee intake is associated with the metabolic syndrome, and especially its blood pressure-component.