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目的建立高效液相色谱法,测定多敏灵片中咖啡因、盐酸多塞平的含量。方法采用高效液相色谱法,以Kromasil C18（250 mm×4.6 mm,5μm）为分析柱,流动相为甲醇-水-三乙胺（75∶25∶1）,流速1 mL/min,检测波长295 nm,柱温为室温。结果咖啡因、盐酸多塞平与其他组分分离良好,且不受其他成分的干扰;咖啡因回归方程为：Y=196 604X＋218 976（r=0.999 8,n=5）,咖啡因在0.08~0.24μg的范围内线性关系良好;盐酸多塞平回归方程为：Y=60 158X＋58 230（r=0.999 9,n=5）,盐酸多塞平在0.04~0.12μg的范围内线性关系良好。方法的平均回收率分别为99.06%、96.67%,精密度（RSD）值分别为1.04%、1.13%。结论本方法操作简便、快速、准确、灵敏,适用于多敏灵片的含量测定。

目的 建立健宝胶囊中淫羊藿苷的含量测定方法。方法 采用高效液相色谱法，色谱柱为C18（150mm×4.6mm)，流动相为乙腈－0.075mol·L^-1磷酸溶液（25：75），流速1.0mL·min^-1，检测波长为270nm。结果 淫羊藿苷进样量在0．06－0．30μm范围内，线性关系良好（r=0.9991)，方法回收率为98．50％（n=5,RSD=1.20%)。结论 本方法准确、简便、快速，适合于该药的质量分析检验。

Bi2WO6 was synthesized with a hydrothermal method at different pHs and used for the degradation of tetracycline （TC） in water. The mesoporous BiEWO6 prepared at pH 1 （BWO-1） displayed the highest adsorption and degradation capacity to TC due to its large surface area and more efficient capacity to separate photogenerated electrons and holes. 97% of TC at 20 mg · L-1 was removed by BWO-1 at 0.5 g-L-1 after 120min irradiation under simulated solar light. Only 31% of the total organic carbon （TOC） was removed after 360 min irradiation although the TC removal reached 100%, suggesting that TC was mainly transformed to intermediate products rather than completely mineralized. The inter- mediates were identified by high-performance liquid chromatography-time of flight-mass spectrometry （HPLC-TOF-MS） and possible photodegradation path- ways were proposed.

Background：The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.Methods：A total of 55 feed ingredients,including 14 corn,13 wheat bran,11 soybean meal and 17 dried distillers grains with solubles（DDGS） as well as 76 complete swine feeds including 7 creep feeds,14 starter feeds,14 grower feeds,18 grower-finisher feeds,10 gestating sow feeds,and 13 lactating sow feeds were randomly collected from15 swine farms located in the Beijing region of China from July to August 2011.Immunoaffinity clean-up,using High-Performance Liquid Chromatography（HPLC） in combination with UV or Fluorescence Detection,was used for quantitative analysis of aflatoxin B,（AFB,）,deoxynivalenol（DON）,zearalenone（ZEA） and ochratoxin A（OTA） in the ingredients and complete feeds.Results：DON and ZEA were the most prevalent mycotoxins found.DON was detected at percentages of 93,92,54,100 and 97%with a mean level of 1.01,0.44,0.05,1.36 and 0.65 ppm in the samples of corn,wheat bran,soybean meal,DDGS and complete feeds,respectively.The detected percentages of ZEA were 100,100,54,100 and 100 with mean levels of 109.1,14.9,9.2,882.7 and 58.9 ppb in the same samples.In the wheat bran and soybean meal samples,the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7,57 and 7%for corn,and 7,14 and 3%for the complete feeds for AFB,,DON and OTA respectively.DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6,88 and 41%,for AFB,,DON and ZEA,respectively.Conclusions：This paper is the first to present data on the natural occurrence of AFB,,DON,ZEA and OTA in ingredients and complete feeds obtained from swine farms in China＇s Beijing region.The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB,and ZEA.

Background： Parkinson＇s disease （PD） patients with long-term levodopa （L-DOPA） treatment are suffering from severe circadian dysfunction. However, it is hard to distinguish that the circadian disturbance in patients is due to the disease progression itself, or is affected by L-DOPA replacement therapy. This study was to investigate the role of L-DOPA on the circadian dysfunction in a rat model of PD. Methods： The rat model of PD was constructed by a bilateral striatal injection with 6-hydroxydopamine （6-OHDA）, followed by administration of saline or 25 mg/kg L-DOPA for 21 consecutive days. Rotarod test, footprint test, and open-field test were carried out to evaluate the motor function. Striatum, suprachiasmatic nucleus （SCN）, liver, and plasma were collected at 6：00, 12：00, 18：00, and 24：00. Quantitative real-time polymerase chain reaction was used to examine the expression of clock genes. Enzyme-linked immunosorbent assay was used to determine the secretion level of cortisol and melatonin. High-performance liquid chromatography was used to measure the neurotransmitters. Analysis of variance was used for data analysis. Results： L-DOPA alleviated the motor deficits induced by 6-OHDA lesions in the footprint and open-field test （P 〈 0.01, P 〈 0.001, respectively）. After L-DOPA treatment, Bmall decreased in the SCN compared with 6-OHDA group at 12：00 （P 〈 0.01） and 24：00 （P 〈 0.001 ）. In the striatum, the expression ofBmall, Rorα was lower than that in the 6-OHDA group at 18：00 （P 〈 0.05） and L-DOPA seemed to delay the peak of Per2 to 24：00. In liver, L-DOPA did not affect the rhythmicity and expression of these clock genes （P 〉 0.05）. In addition, the cortisol secretion was increased （P 〉 0.05）, but melatonin was further inhibited after L-DOPA treatment at 6：00 （P 〈 0.01）. Conclusions： In the circadian system of advanced PD rat models, circadian dysfunction is not only contributed by the degeneration of the disease itself but also long-term L-DOPA therapy may further aggravate it.

Saffron, obtained from the flower stigmas of Crocus sativus L., is one of the most expensive food spices. The introduction of saffron in alpine areas could help to broaden and diversify the activities of mountain multifunctional farms, with a positive impact on economy and land management. According to ISO 3632（2010/2011）, saffron can be classified into three categories of quality（I, II, III） depending on the concentration of the three main metabolites responsible for its characteristic colour, flavor and aroma： Crocin, Picrocrocin and Safranal. This study represents the first investigation of the quality of saffron produced in the Italian Alps evaluated with spectrophotometry, HPLC, solid-phase microextraction（SPME）, and gas chromatographic analysis combined with mass spectrometry（GC/MS）. The experiments used Crocus sativus stigmas produced in 2012-2013 in different areas of the Central Italian Alps were located at an altitude between 720 and 1200 m a.s.l.. Results obtained were compared to commercial saffron. The analyses confirmed that all samples can be classified in the first quality category according to the ISO classification. This high quality is also confirmed by HPLC analysis. Moreover, the SPME-GC/MS analysis identified some differences in the aromatic profile of saffron samples, in particular regarding safranal concentration. A preliminary assessment of the economic viability of high quality saffron production for local markets was also performed. Our study provides valid information regarding the quality and economic sustainability of saffron production in the alpine area confirming this crop as a good candidate for a new source of income for multifunctional farms in mountain areas.

Sedimentary pigments are useful proxy indicators of phytoplankton biomass, community structure, primary productivity and human influence in lacustrine and oceanic ecosystems. Pigments are relatively labile due to their complex chemical structures, which makes the extraction and analysis of sedimentary pigments challenging. In addition, it is important to select appropriate methods to study sedimentary pigments in regions which lack previous investigations. In this study, we adopted the L9（34） orthogonal design to develop methods of extraction and HPLC （high performance liquid chromatography） analysis of sedimentary pigments at two lakes on the Tibetan Plateau： meromictic lake-Dagze Co and dimictic lake-Jiang Co. The orthogonal design comprises 9 combinations of various parameters for extraction and HPLC analysis. The results show that the type and volume of solvent are the most important factors for pigment extraction, and the mobile phase and column selection are the most important for HPLC analysis. For the study sites, we found that the best methods to extract sedimentary pigments are as follows： the use of a mixture of acetone：methanol：water （80： 15：5, v：v：v） as the extraction solvent; sol- vent/sample ratio of 10 mL/g; sonication for 30 s and standing extraction for 6 h. The best methods for HPLC analysis are as follows： Zorbax Eclipse plus C8 column with mobile phase A, methanol：acetonitrile：0.25 M aqueous pyridine （50： 25：25, v ： v ： v） and mobile phase B, methanol： acetonitrile： acetone （20： 60： 20, v： v： v）; pH of mobile phase A adjusted to 6 with acetic acid; and HPLC column temperature maintained at 40~C. The study provides an experimental basis for future investigations of past changes in primary productivity and the response of lake ecosystems to climate change and human activities on the Tibetan Plateau.

Aim： To study the metabolic and pharmacokinetic profile of scutellarin, an active component from the medical plant Erigeron breviscapus （Vant） Hand-Mazz, and to investigate the mechanisms underlying the low bioavailability of scutellarin though oral or intravenous administration in rats. Methods： HPLC method was developed for simultaneous detection of scutellarin and scutellarein （the aglycone of scutellarin） in rat plasma, urine and feces. The in vitro metabolic stability study was carried out in rat liver microsomes from different genders. Results： After a single oral dose of scutellarin （400 mg/kg）, the plasma concentrations of scutellarin and scutellarein in female rats were significantly higher than in male ones. Between the female and male rats, significant differences in AUC, tmax2 and Cmax2 for scutel- larin were found. The pharmacokinetic parameters of scutellarin in the urine also showed significant gender differences. After a single oral dose of scutellarin （400 mg/kg）, the total percentage excretion of scutellarein in male and female rats was 16.5% and 8.61%, respectively. The total percentage excretion of scutellarin and scutellarein in the feces was higher with oral administration than with intravenous administration. The in vitro t1/2 and GLint value for scutellarin in male rats was significantly higher than that in female rats. Conclusion： The results suggest that a large amount of ingested scutellarin was metabolized into scutellarein in the gastrointestinal tract and then excreted with the feces, leading to the extremely low oral bioavailability of scutellarin. The gender differences of pharma- cokinetic parameters of scutellarin and scutellarein are due to the higher GLint and lower absorption in male rats.

Aim： Para-aminosalicylic acid （PAS） is effective in the treatment of manganism-induced neurotoxicity （manganism）. In this study we investigated the roles of P-glycoprotein （MDRla） and multidrug resistance protein （MRP） in transporting PAS and its N-acetylated metabolite AcPAS through blood-brain barrier. Methods： MDRla-null or wild-type mice were intravenously injected with PAS （200 mg/kg）. Thirty minutes after the injection, blood samples and brains were collected, and the concentrations of PAS and AcPAS in brain capillaries and parenchyma were measured using HPLC. Both MDCK-MDR1 and MDCK-MRP1 cells that overexpressed P-gp and MRP1, respectively, were used in two-chamber Transwell transport studies in vitro. Results： After injection of PAS, the brain concentration of PAS was substantially higher in MDRla-null mice than in wild-type mice, but the brain concentration of AcPAS had no significant difference between MDRla-null mice and wild-type mice. Concomitant injection of PAS with the MRP-specific inhibitor MK-571 （50 mg/kg） further increased the brain concentration of PAS in MDRla-null mice, and increased the brain concentration of AcPAS in both MDRla-null mice and wild-type mice. Two-chamber Transwell studies with MDCK- MDR1 cells demonstrated that PAS was not only a substrate but also a competitive inhibitor of P-gp, while AcPAS was not a substrate of P-gp. Two-chamber Transwell studies with the MDCK-MRP1 cells showed that MRP1 had the ability to transport both PAS and AcPAS across the BBB. Conclusion： P-gp plays a major role in the efflux of PAS from brain parenchyma into blood in mice, while MRP1 is involved in both PAS and AcPAS transport in the brain.

The activation of adenosine A1 receptors is important for protecting against ischemic brain injury and pretreatment with electroacupuncture has been shown to mitigate ischemic brain insult. The aim of this study was to test whether the adenosine A1 receptor mediates electroacupuncture pretreatment-induced neuroprotection against ischemic brain injury. We first performed 30 minutes of electroacupuncture pretreatment at the Baihui acupoint（GV20）, delivered with a current of 1 mA, a frequency of 2/15 Hz, and a depth of 1 mm. High-performance liquid chromatography found that adenosine triphosphate and adenosine levels peaked in the cerebral cortex at 15 minutes and 120 minutes after electroacupuncture pretreatment, respectively. We further examined the effect of 15 or 120 minutes electroacupuncture treatment on ischemic brain injury in a rat middle cerebral artery-occlusion model. We found that at 24 hours reperfusion,120 minutes after electroacupuncture pretreatment, but not for 15 minutes, significantly reduced behavioral deficits and infarct volumes. Last, we demonstrated that the protective effect gained by 120 minutes after electroacupuncture treatment before ischemic injury was abolished by pretreatment with the A1-receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine（1 mg/kg, intraperitoneally）. Our results suggest that pretreatment with electroacupuncture at the Baihui acupoint elicits protection against transient cerebral ischemia via action at adenosine A1 receptors.