GC-MS联用技术结合化学计量学方法分析厚朴叶挥发油成分

利用水蒸气蒸馏法提取湖南产厚朴叶的挥发油成分,采用GC-MS联用技术结合化学计量学方法(直观推导式演进特征投影法和选择性离子法)进行分析,同时结合程序升温保留指数辅助定性。结果共鉴定出54种化合物,占挥发油总量的84.95%。主要化学成分为α-、β-和γ-桉油醇,含量分别为13.10%、28.21%和14.67%。此外,含量较高的化合物还有α-蒎烯(2.96%)、芳樟醇(1.71%)、丹皮酚(1.88%)、石竹烯(2.04%)、佛术烯(3.60%)、α-瑟林烯(3.84%)和[1AR-(1Aα,4α,4Aβ,7Bα)]-1A,2,3,4,4A,5,6,7B-八氢化-1,1,4,7-四甲基-1H-环丙烯并[E]奥(1.34%)。研究表明,将化学计量学方法用于中药挥发油成分的分析可提高定性分析的准确性。所得结果可为厚朴药植物资源的开发利用提供依据。     

Qualitative and Quantitative Analysis of Alkaloids in Cortex Phellodendri by HPLC-ESI-MS/MS and HPLC-DAD

A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was applied to the qualitative and quantitative analyses of alkaloids in Cortex Phellodendri(CP) samples, and to the differentiation of two species of CP, Cortex Phellodendri Chinensis(CPC) and Cortex Phellodendri Amurensis(CPA). Twenty-two peaks appeared in the HPLC-MS base peak chromatogram of CP detec...     

单扫描示波极谱法连续测定羊乳、黄芪、白鲜皮、蕨菜中铜和锌

研究了在HCl-KSCN底液中用单扫描示波极谱法连续测定羊乳、黄芪、白鲜皮、蕨菜中铜和锌含量的方法。在此底液中,铜和锌分别在-0．42和-1．03 V(vs．SCE)处产生一敏锐的二阶导数波,检出限分别为0．005和0．01 mg·L-1,线性范围分别为0．01～8．00和0．01-10．00 mg·L-1。应用此法测定羊乳、黄芪、白鲜皮、蕨菜中铜和锌含量,回收率在97．0％～101．7％。     

MRI, CT, and plain film appearance of anterior spina bifida

Anterior spina bifida or butterfly vertebral body has a well known and characteristic appearance on plain film and CT. Its appearance on magnetic resonance imaging also appears to be characteristic and should not be mistaken for more serious abnormalities.     

Optimizing the imaging of the monkey auditory cortex: sparse vs. continuous fMRI

The noninvasive imaging of the monkey auditory system with functional magnetic resonance imaging (fMRI) can bridge the gap between electrophysiological studies in monkeys and imaging studies in humans. Some of the recent imaging of monkey auditory cortical and subcortical structures relies on a technique of “sparse imaging,” which was developed in human studies to sidestep the negative influence of scanner noise by adding periods of silence in between volume acquisition. Among the various aspects that have gone into the ongoing optimization of fMRI of the monkey auditory cortex, replacing the more common continuous-imaging paradigm with sparse imaging seemed to us to make the most obvious difference in the amount of activity that we could reliably obtain from awake or anesthetized animals. Here, we directly compare the sparse- and continuous-imaging paradigms in anesthetized animals. We document a strikingly greater auditory response with sparse imaging, both quantitatively and qualitatively, which includes a more expansive and robust tonotopic organization. There were instances where continuous imaging could better reveal organizational properties that sparse imaging missed, such as aspects of the hierarchical organization of auditory cortex. We consider the choice of imaging paradigm as a key component in optimizing the fMRI of the monkey auditory cortex.     

Development and validation of an LC-MS-MS method for determination of methyl kulonate in rat plasma

A sensitive, rapid and specific LC‐MS‐MS method was established and validated for determination of methyl kulonate, a major bioactive constituent isolated from Meliae Cortex, in rat plasma. Plasma samples were treated by precipitating protein with methanol and were chromatographed using a Capcell Pak C₁₈ column (100 × 4.6 mm, 5 µm) with the mobile phase comprising a mixture of methanol, 10 m m ammonium formate and formic acid (95:5:0.1, v/v/v). Detection and quantification were performed by mass spectrometry in the multiple reaction monitoring mode with positive atmospheric ionization at m/z 467 → 311 for methyl kulonate, and m/z 469 → 451 for dubione B (internal standard), respectively. A good linear response was observed over the concentration range 1.00–500 ng/mL with the lower limit of quantification 1.00 ng/mL in rat plasma. The method also afforded satisfactory results base on sensitivity, specificity, precision, accuracy, recovery, freeze–thaw and long‐time stability. The validated method was successfully applied to determine the pharmacokinetic properties of methyl kulonate in rats after oral administration at dose of 100 mg/kg. This pharmacokinetic study of methyl kulonate is reported here for the first time. Copyright © 2011 John Wiley & Sons, Ltd.     

高效液相色谱法测定黄柏中盐酸小檗碱含量的不确定度评估

介绍一种高效液相色谱法测定含量的不确定度计算方法.通过黄柏中盐酸小檗碱含量测定结果,对产生不确定度的各分量进行计算,研究测量不确定度的主要分量,以控制检验环节的质量,保证结果准确度.     

移液枪头式固相微萃取-高效液相色谱法测定细胞培养液中的4种生物碱

建立了移液枪头式固相微萃取(SPME)-高效液相色谱检测细胞培养液中4种生物碱(黄柏碱、药根碱、巴马丁和小檗碱)的分析方法。以甲基丙烯酸为反应单体、乙二醇二甲基丙烯酸酯为交联剂、偶氮二异丁腈为引发剂,在移液枪头内进行原位聚合反应,制备含有弱阳离子交换整体固定相的SPME枪头。样品经SPME净化后,用高效液相色谱-紫外检测法进行分析,流动相为乙腈-磷酸二氢钾溶液(0.05 mol/L,pH 4),紫外检测波长为270 nm,外标法定量。4种生物碱的检出限(S/N=3)为0.16~0.39μg/L;以空白细胞培养液进行加标回收率试验,加标回收率为92.73%~97.91%,相对标准偏差(RSD)为0.14%~3.31%。该方法简单、灵敏、准确,能够用于细胞培养液中微量生物碱的分析研究。     

Migration of the anterior segment following anterior commissure advancement: A case report

A 53-year-old man with severe vocal fold atrophy underwent bilateral type 1 thyroplasty and anterior commissure advancement. Postoperatively, he developed a strained voice with less projection and volume than prior to surgery. This was verified by objective assessment of vocal function. Videoendoscopy revealed bilateral false vocal fold fullness and blunting of the anterior commissure. Magnetic resonance imaging demonstrated cephalic migration of the posterior ends of the implants and retrusion of the anterior commissure segment. Surgical exploration revealed that the type 1 implants had rotated and buckled. The anterior commissure segment was rotated and displaced inferiorly, and its inferior surface was tethered to the cricoid by scar tissue. The implants were removed, the anterior segment was repositioned and rigidly fixed, and bilateral lipoinjection performed. Vocal function was significantly improved, and endoscopy revealed normal tension and length of the vocal folds and restoration of the anterior commissure. This case demonstrates the importance of stable fixation during laryngeal framework surgery