土壤干旱胁迫对毛鸡骨草幼苗生长及某些生理特性的影响

以毛鸡骨草幼苗为试验材料,测定毛鸡骨草在不同水分条件下的生长状况和相关的生理生化指标,结果表明:随着干旱胁迫的增加,毛鸡骨草幼苗的株高、茎粗、复叶长等呈递减趋势,根直径、须根数呈递增趋势;根、叶片脯氨酸含量和叶片可溶性糖的含量均呈先降低再上升的趋势,水势随干旱胁迫的加剧呈先上升后降低的趋势,根系活力随干旱胁迫的加剧呈递减趋势。但是,在严重干旱胁迫下,各生长指标的增长均受到明显的抑制。     

基于绿色低共熔溶剂法高效提取鸡骨草中的黄酮和皂苷

为了研究鸡骨草中总黄酮和总皂苷的最佳提取工艺,通过单因素试验和星点设计-响应面法,对低共熔溶剂的性质(如种类、组分摩尔比、含水量)、提取温度、提取时间、液料比等多个因素进行考察。结果显示,总黄酮的最佳提取条件为:摩尔比1∶2、含水量30%的氯化胆碱/乙二醇作溶剂,提取温度80℃,提取时间40min,液料比15∶1(mL/g);总皂苷的最佳提取条件为∶摩尔比1∶4、含水量25%的氯化胆碱/乳酸作溶剂,提取温度80℃,提取时间64min,液料比56∶1(mL/g)。在最佳条件下,总黄酮和总皂苷的提取率较传统提取溶剂分别提高了33.3%和96.4%。本研究为鸡骨草中黄酮和皂苷的高效、安全提取提供了一条新思路。     

大孔吸附树脂提取分离翅果油树叶总黄酮的研究

通过吸附容量和洗脱效果的选择,从5种大孔吸附树脂中确定出LSA—10树脂最适于翅果油树叶中总黄酮的吸附和分离。研究了该树脂吸附翅果油树叶中总黄酮的最佳工艺条件,其结果为：(1)洗脱剂为50％～70％乙醇溶液;(2)上柱液pH=4时,此树脂对翅果油树叶中总黄酮的吸附容量最大;(3)吸附容量随着吸附时间的增加而升高,最佳吸附时间为8～10h;(4)随着上柱液浓度的增加,吸附容量也相应增加,而且浓度越大,这种差别越明显,但浓度不宜过高,以澄清为好。     

Hepatoprotective effect of total flavonoids from Laggera alata against carbon tetrachloride-induced injury in primary cultured neonatal rat hepatocytes and in rats with hepatic damage

Summary The hepatoprotective activities of total flavonoids of Laggera alata (TFLA) were evaluated by carbon tetrachloride (CCl₄)-induced injury in primary cultured neonatal rat hepatocytes and in rats with hepatic damage. In vitro, TFLA at a concentration range of 1–100 g/ml improved cell viability and inhibited cellular leakage of two enzymes, hepatocyte aspartate aminotransferase (AST) and alanine aminotransferase (ALT), caused by CCl₄. In vivo, oral treatment with TFLA at doses of 50, 100, and 200 mg/kg significantly reduced the levels of AST, ALT, total protein, and albumin in serum and the hydroxyproline and sialic acid levels in liver. Histopathological examinations revealed that liver damage were improved when treated with TFLA. Meanwhile, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide radicals scavenging activities of TFLA were also determinated. To understand the exact components of TFLA responsible for the hepatoprotective effect, nine flavonoid compounds were isolated and identified from TFLA. In conclusion, the present investigation was the first to verify the hepatoprotective effect of L. alata in vitro and in vivo. The hepatoprotective action of TFLA is likely related to its potent antioxidative and anti-inflammatory activity. Neutralizing reactive oxygen species by nonenzymatic mechanisms and enhancing the activity of original natural hepatic-antioxidant enzymes may be the main mechanisms of TFLA against CCl₄-induced injury.     

Characterization of an Acidic Polysaccharides from Carrot and Its Hepatoprotective Effect on Alcoholic Liver Injury in Mice

The characteristics of acidic polysaccharides extracted from Daucus carota L. var. sativa Hoffm were investigated and its hepatoprotective effects on alcoholic liver injury were determined in the mice model. A carrot polysaccharide (CPS-I: Carrot polysaccharide-I) with the molecular weight of 3.40×10⁴ kDa was isolated from Daucus carota L. and purified by diethylaminoethyl-52 and Sephadex G-150 column chromatography. The components were analyzed by HPLC, which revealed that CPS-I consisted of galacturonic acid, rhamnose, xylose, arabinose, fructose, and galactose at a relative ratio of 1 : 3.16 : 1.13 : 5.53 : 3.45 : 7.76. Structural characterization analysis suggested that CPS-I was mainly composed of →6)-β-D-Galp-(1→ and →5)-α-L-Araf-(1→. The hepatoprotective effect of CPS-I was evaluated by alcoholic liver injury mice model. The results showed that the administration of CPS-I (300 mg/kg/day) alleviated the alcoholic liver injury in mice by increasing the levels of ADH and ALDH and reducing oxidative stress. CPS-I ameliorated the pathological changes of liver characterized by lipid accumulation, and reduced the number of lipid droplets.     

三种车前草的黄酮提取、纯化及其抗氧化活性分析

本研究采用响应面设计优化超声辅助提取车前总黄酮的最佳条件,然后用此条件提取大车前和平车前总黄酮,并探究大孔树脂纯化对三种车前草总黄酮抗氧化活性的影响。结果表明,在超声温度60℃、乙醇浓度70%的条件下,车前总黄酮最佳提取工艺参数为液料比20:1 m L/g、超声时间80 min、超声功率210 W,车前、大车前和平车前的总黄酮得率分别为5.04%、2.86%和1.22%。无论是纯化前还是纯化后,大车前总黄酮的还原力和对羟基自由基的清除作用最强,平车前最弱;车前总黄酮对DPPH自由基的清除作用最大,平车前最弱。纯化前后的还原力和对DPPH自由基、羟基自由基的清除作用都接近Vc的水平。     

四种药用植物花总黄酮类物质提取及抗氧化性研究

目的:采用微波辅助法提取4种药用植物花中总黄酮类化合物,并研究其抗氧化性。方法:利用邻二氮菲-Fe2+-H2O2体系,研究其提取物清除羟基自由基(.OH)的能力,用普鲁士蓝法对其还原能力进行研究。结果:大蓟刺儿菜花总黄酮含量最高,夏至草花总黄酮含量最低,4种药用植物花提取物均有不同抗氧化能力。结论:药用植物花抗氧化能力与黄酮含量、结构有关。     

Baseline Sensitivity of Populations of Phytophthora capsici from China to Three Carboxylic Acid Amide (CAA) Fungicides and Sequence Analysis of Cholinephosphotranferases from a CAA‐sensitive Isolate and CAA‐resistant Laboratory Mutants

During 2006–2008, 572 isolates of Phytophthora capsici were collected from seven provinces in China, and their sensitivities to three carboxylic acid amides (CAA), dimethomorph, flumorph and pyrimorph were determined. Of these isolates, 90 isolates without a history of exposure to CAA fungicides (CAAs) were used to set up the baseline sensitivity. Baseline EC₅₀ values ranged from 0.122 to 0.203 (mean ± SD, 0.154 ± 0.022) μg ml^?1 for dimethomorph, from 0.301 to 0.487 (mean ± SD, 0.373 ± 0.043) μg ml^?1 for flumorph and from 0.557 to 0.944 (mean ± SD, 0.712 ± 0.082) μg ml^?1 for pyrimorph, respectively. The other 482 isolates were tested with a single discriminatory dose and were completely inhibited at 0.5 μg ml^?1 of dimethomorph. Four CAA‐resistant mutants were generated by repeated exposure to dimethomorph in vitro. As compared to the parental wild‐type isolate, the four CAA‐resistant mutants showed similar fitness in hyphal growth, sporulation in vitro and pathogenicity in vivo. Mutants resistant to CAAs in the in vitro assay caused visible lesions on pepper stems or roots treated with the recommended dose of dimethomorph. Previous studies upon the mode of action of CAAs suggested that these fungicides maybe inhibit phospholipid biosynthesis and that the primary target could be the cholinephosphotranferase (CPT), which is referred to aminoalcoholphosphotransferases (AAPTs). We sequenced and analyzed two CPT (AAPT1 and AAPT2) genes in P. capsici. Based on the cDNA sequence, we found that the AAPT1 and AAPT2 gene span 1538 and 1459 bp and were interrupted by five and three introns, respectively. There was no difference between the parental wild‐type isolate and the four CAA‐resistant mutants in the amino acid sequences of AAPT1 and AAPT2 gene. So, it was assumed that the resistance to dimethomorph was not due to mutations in the amino acid sequence of these two possible target genes.     

匹多莫德对反复呼吸道感染患儿外周血T淋巴细胞亚群变化的影响及其临床疗效

目的:研究匹多莫德治疗反复呼吸道感染患儿的临床疗效,并探讨其对患儿外周血T淋巴细胞亚群变化的影响。方法:选择我院收治的160例反复呼吸道感染患儿,根据临床治疗方法将其分成研究组(80例)与对照组(80例),对照组采用抗生素或抗病毒、退热、止咳、平喘与化痰等对症治疗,研究组则在对照组的基础上再加用匹多莫德口服。比较两组患儿外周血T淋巴细胞亚群变化并分析其临床疗效。结果:研究组治疗总有效率显著优于对照组(P0.05)。研究组治疗后CD3+、CD4+、CD4+/CD8+水平,与治疗前比较明显升高(P0.05),与对照组同期比较具有明显的差异(P0.05)。研究组患儿治疗后白细胞计数及中性粒细胞水平,与治疗前比较无明显差异(P0.05),与对照组同期比较无明显差异(P0.05);对照组治疗前后白细胞计数及中性粒细胞水平无明显差异(P0.05)。研究组患儿咳嗽、发热、喘息、肺部啰音消失时间以及抗生素使用时间均明显少于对照组(P0.01)。研究组与对照组患儿治疗过程中均未发生明显的药物不良反应。结论:匹多莫德治疗反复呼吸道感染患儿疗效确切,能有效改善T淋巴细胞的免疫功能,值得临床推广与应用。     

Heliotropiumides A and B,new phenolamides with N-carbamoyl putrescine moiety from Heliotropium foertherianum collected in Hawaii and their biological activities

Two new compounds heliotropiumides A (1) and B (2), phenolamides each with an uncommon carbamoyl putrescine moiety, were isolated from the seeds of a naturalized Hawaiian higher plant, Heliotropium foertherianum Diane & Hilger in the borage family, which is widely used for the treatment of ciguatera fish poisoning. The structures of compounds 1 and 2 were characterized based on MS spectroscopic and NMR analysis, and DP4+ calculations. The absolute configuration (AC) of compound 1 was determined by comparison of its optical rotation with those reported in literature. Compound 2 showed inhibition against NF-κB with an IC₅₀ value of 36 μM.     

Anti-Diabetic Effects and Molecular Mechanisms of Amide Alkaloids from Piper longum Based on Network Pharmacology Integrated with Cellular Assays

Piper longum is a well-known spice and traditional medicine. It was revealed to possess anti-diabetic activity, but few information about its active component and underlying mechanism could be available. In this study, retrofractamides A ( 1 ) and C ( 2 ) isolated from P. longum showed potent inhibitory activity against PTP1B. Therefore, the potential mechanism was predicted by network pharmacology and molecular docking. PI3K/AKT was obtained as the most remarkable pathway against type 2 diabetes mellitus (T2DM), and AKT1 and GSK3β were yielded as the top two core targets of retrofractamides A ( 1 ) and C ( 2 ). Molecular docking of compounds with AKT1 and GSK3β showed strong binding affinity between them. Additionally, cellular experiments with a L6 cell model was conducted to further verify the above predictions. Results indicated that retrofractamides A ( 1 ) and C ( 2 ) exerted anti-diabetic effect via activating PI3K/AKT pathway, and they promoted glucose consumption, glucose uptake, glycogen synthesis and glycolysis.     

基于PI3K/AKT/mTOR信号通路探讨半枝莲总黄酮对脑缺血再灌注损伤大鼠神经功能和氧化应激损伤的影响

摘要 目的：基于磷脂酰肌醇3激酶（PI3K）/丝氨酸苏氨酸蛋白激酶（Akt）/哺乳动物的雷帕霉素（mTOR）信号通路探究半枝莲总黄酮对脑缺血再灌注损伤（CIRI）大鼠神经功能和氧化应激损伤的影响。方法：选取70只SPF级雄性SD大鼠,采用线栓法制备大脑中动脉闭塞（MCAO）模型,将造模成功的60只大鼠随机分为模型组、半枝莲总黄酮低剂量组（半枝莲L组）、半枝莲总黄酮中剂量组（半枝莲M组）、半枝莲总黄酮高剂量组（半枝莲H组）、control组、LY294002组,每组10只,剩余10只大鼠作为sham组。半枝莲L、M、H组分别给予半枝莲总黄酮0.1、0.2、0.4 g/kg溶于2 mL生理盐水灌胃,control组给予尼莫地平0.3 g/kg溶于2 mL生理盐水灌胃,LY294002组给予半枝莲总黄酮0.4 g/kg溶于2 mL生理盐水灌胃,同时侧脑室注射PI3K抑制剂LY294002 20 μmol/L,模型组和sham组给予等量的生理盐水灌胃。分别比较各组大鼠神经功能评分、脑组织积水量、脑梗死体积、脑组织病理学变化、脑组织氧化应激水平、脑组织中p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR蛋白表达。结果：各组大鼠神经功能评分、脑组织含水量、脑梗死体积、丙二醛（MDA）水平比较,模型组明显高于sham组,半枝莲L、M、H组、control组均低于模型组,且半枝莲H组优于半枝莲L、M组,但LY294002组高于半枝莲H组（P<0.05）;各组大鼠超氧化物岐化酶（SOD）水平和p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR蛋白表达比较,模型组明显低于sham组,半枝莲L、M、H组、control组均高于模型组,且半枝莲H组优于半枝莲L、M组,但LY294002组低于半枝莲H组（P<0.05）。结论：半枝莲总黄酮可能通过激活PI3K/Akt/mTOR信号通路发挥对CIRI大鼠神经功能和氧化应激损伤的改善作用,且高剂量半枝莲总黄酮的改善作用最显著。     

Town and Gender Effects on Hair Lead Levels in Children from Three Sardinian Towns (Italy) with Different Environmental Backgrounds

This study reports hair lead (PbH) levels measured in 2002 in 193 children from three Sardinian towns: Carbonia, Gonnesa, and Sinnai. Carbonia and Gonnesa are in a polluted area of Sardinia due to their vicinity to the industrial zone of Portovesme. As a consequence of its economy and location, Sinnai is not exposed to lead pollution. PbH concentrations were determined by inductively coupled plasma atomic absorption spectrometry. The aim of this study was to evaluate if hair is a reliable biomarker to determine different degrees of exposure of populations to lead pollution and if there is a tendency to higher accumulation by males or females. The girls of Carbonia had the highest mean PbH value (2.21 microg/g), followed by the Gonnesa girls (2.03 microg/g), Carbonia boys (1.86 microg/g), Gonnesa boys (0.91 microg/g), and finally the Sinnai boys (0.68 microg/g) and girls (0.50 microg/g). Two-way analysis of covariance, with age as covariate, revealed a significant effect of town and sex on log PbH. Spearman's rank correlation coefficient indicated a significant positive concordance between PbH levels and gender (score for males=1, females=2). The results suggest that hair is a reliable biomarker to determine different levels of exposure of populations to lead pollution, and they indicate that females tend to accumulate lead in the hair more than males of the same age.     

Crystal structure of the polyextremophilic alpha-amylase AmyB from Halothermothrix orenii: details of a productive enzyme-substrate complex and an N domain with a role in binding raw starch

The gene for a membrane-bound, halophilic, and thermostable α-amylase, AmyB, from Halothermothrix orenii was cloned and sequenced. The crystal structure shows that, in addition to the typical domain organization of family 13 glycoside hydrolases, AmyB carries an additional N-terminal domain (N domain) that forms a large groove—the N-C groove—some 30 Å away from the active site. The structure of AmyB with the inhibitor acarbose at 1.35 Å resolution shows that a nonasaccharide has been synthesized through successive transglycosylation reactions of acarbose. Unexpectedly, in a complex of wild-type AmyB with α-cyclodextrin and maltoheptaose at 2.2 Å resolution, a maltotetraose molecule is bound in subsites − 1 to + 3, spanning the cleavage point at − 1/+ 1, with the − 1 glucosyl residue present as a ²S_o skew boat. This wild-type AmyB complex was obtained in the presence of a large excess of substrate, a condition under which it is possible to capture Michaelis complexes, which may explain the observed binding across − 1/+ 1 and ring distortion. We observe three methionine side chains that serve as “binding platforms” for glucosyl rings in AmyB, a seemingly rare occurrence in carbohydrate-binding proteins. The structures and results from the biochemical characterization of AmyB and AmyB lacking the N domain show that the N domain increases binding of the enzyme to raw starch. Furthermore, theoretical modeling suggests that the N-C groove can accommodate, spatially and chemically, large substrates such as A-starch.