Synaptogenesis in Co-Culture of Neurons of Dorsal Root Ganglia and Spinal Cord

In co-culture of spinal cord and dorsal root ganglion (DRG) neurons, we studied at different terms of culturing postsynaptic currents in DRG neurons evoked by direct electrical stimulation of single spinal neurons using a voltage-clamp technique in the whole-cell configuration. According to the reversal potential and sensitivity to bicuculline, these currents were classified as inhibitory postsynaptic currents (IPSC) carried by Cl^- ions through GABA_A receptors. During neuronal development in dissociated co-culture, the amplitude of evoked IPSC and their time to peak significantly increased. The time to peak of spontaneous IPSC (sIPSC) in DRG neurons remained unchanged, while the frequency of these currents increased with increasing culturing time. It is concluded that under culturing conditions spinal neurons establish inhibitory synaptic contacts with the somata of DRG neurons, and the number of such functional contacts increases in the course of culturing. Our findings show that in dissociated co-culture the process of formation of inhibitory synapses on the axon terminals of primary afferent neurons is akin to that realized in vivo, but with dissimilar topography of distribution of such synapses.     

Histochemical Localization of Caldesmon in the CNS and Ganglia of the Mouse

The author has recently reported the distribution of the cytoskeleton-associated protein caldesmon in spleen and lymph nodes detected with different antibodies against caldesmon (J Histochem Cytochem 58:183–193, 2010). Here the author reports the distribution of caldesmon in the CNS and ganglia of the mouse using the same antibodies. Western blot analysis of mouse brain and spinal cord showed the preponderance of l-caldesmon and suggested at least two l-caldesmon isoforms in the brain. Immunostaining revealed the predominant reactivity of smooth muscle cells and cells resembling pericytes of many large and small blood vessels, ependymocytes, and secretory cells of the pineal gland and pituitary gland. Neuronal perikarya and neuropil in general displayed no or weak immunoreactivity, but there was stronger labeling of neuronal perikarya in dorsal root and trigeminal ganglia. In the brain, staining of the neuropil was stronger in the molecular layers of the dentate gyrus and cerebellum. Results show that caldesmon is expressed in many different cell types in the CNS and ganglia, consistent with the notion that l-caldesmon is ubiquitously expressed, but it appears most concentrated in smooth muscle cells, pericytes, epithelial cells, secretory cells, and neuronal perikarya in dorsal root and trigeminal ganglia.     

眼镜蛇毒对大鼠脊髓和脊神经节一氧化氮合酶表达的影响

目的 观察眼镜蛇毒对脊髓和脊神经节一氧化氮合酶(NOS)表达的影响。方法 将眼镜蛇毒注入大鼠右侧大腿后部,采用还原型尼克酰胺嘌呤二核苷酸脱氢酶(NADPH．d)法显示NOS的表达。结果 在眼镜蛇毒注射组,脊髓和脊神经节内的NOS阳性神经元和深染NOS阳性神经元明显多于注入生理盐水组和正常对照组。结论 注入眼镜蛇毒能上调大鼠脊髓和脊神经节NOS表达。     

Effect of Bicuculline on GABA-Activated Transmembrane Ion Currents in Neurons of the Rat Spinal Ganglia

We obtained quantitative estimates of the effect exerted by a blocker of GABAA receptors, bicuculline, on GABA-activated transmembrane ion currents in isolated neurons from the rat spinal ganglia. The currents were evoked by short (20 msec) local GABA applications. Increases in the bicuculline concentration from 10 nM to 2 M progressively decreased the amplitude of GABA-activated ion currents; 5 M of the blocker completely suppressed these currents, while washing out recovered them. The dependence between the level of bicuculline-induced blockade and concentration of the agent was nonlinear and could be satisfactorily fitted by a reverse logistic function. Within the studied concentration range, bicuculline exerted no influence on the kinetic parameters of the current rising and falling phases.     

生物转化对二甲苯生成对苯二甲酸的初步研究

对苯二甲酸是生产聚酯的主要原料,其生产方法主要是采用化学合成法。随着生物转化与生物催化研究的深入,其高效、环保、节能等优势越来越明显。筛选能够生物转化对二甲苯生成对苯二甲酸的菌株将会为生物催化法生产对苯二甲酸打下基础。通过建立筛选模型,利用唯一碳源法从土壤中分离筛选得到微生物16,经鉴定为嗜麦芽窄食单胞菌和睾丸酮丛毛单胞菌的混合菌株,该微生物可以利用对二甲苯为底物生物转化生成对苯二甲酸。实验中对诱导剂进行了选择,表明甲苯对该反应有明显的诱导作用,最佳诱导剂加入量为200mg／L。发酵液中对苯二甲酸及中间产物采用高效液相色谱法测定。     

Measurement of muramic acid in marine sediments by high performance liquid chromatography

Bacterial biomass in marine sediments may be estimated from the amount of muramic acid present. A method for determining muramic acid by high performance liquid chromatography is described, which is simpler and faster than other methods. Muramic acid is released from sediment by acid hydrolysis, and assayed as an o-phthaldialdehyde derivative.     

高效液相色谱法同时检测棉花根中的多种植物激素

目的：探寻高效液相色谱同时检测棉花根中多种植物激素含量的方法。方法：采用WatersC18反相色谱柱（4.6×250mm,5μm）,在柱温为35℃、流速为1mL.min-1的条件下,以乙腈和三乙胺溶液为流动相梯度洗脱,在每种物质的保留时间附近切换至最大吸收峰（GA3除外）波长作为检测波长,并与254nm同一波长检测多种植物激素含量的方法进行比较,分离和检测棉花根中的玉米素（Z）、玉米素核苷（ZR）、赤霉酸（GA3）、生长素（IAA）和脱落酸（ABA）的含量。结果：切换波长法检测5种植物激素的灵敏度和回收率均较高,检出限均较低。回收率为：Z 96.82%、ZR 94.14%、GA3 92.75%、IAA 93.38%、ABA 95.57%;检出限为：Z 0.1μg.mL-1、ZR 0.1μg.mL-1、GA3 0.5μg.mL-1、IAA 0.3μg.mL-1;ABA 0.05μg.mL-1,能准确检测出棉花根中Z、ZR、GA3、IAA和ABA的含量。结论：采用Waters C18反相色谱柱（4.6×250mm,5μm）,在柱温为35℃、流速为1mL.min-1的条件下,以乙腈和三乙胺溶液为流动相梯度洗脱,结合切换波长法能同时检测出植物组织中多种植物激素含量。     

刺五加叶中金丝桃苷含量的测定

用高效液相色谱法测定了刺五加(Acanthopanax senticosus(Rupr.&Maxin)Harms)叶中金丝桃苷(hyperin)的含量。色谱柱为C18柱,流动相为甲醇和0.025mol L-1磷酸,比例为V甲醇:V0.025mol.L-1磷酸.=55:45(混合后用三乙胺调pH3.0￣3.2),检测波长360nm。样品用甲醇超声提取。结果表明,金丝桃苷峰形良好,与其他组分的色谱峰达到基线分离。加样回收率为104%,相对标准偏差RSD为5.38%。本研究为刺五加叶中金丝桃苷含量的测定建立了一种可靠的方法。     

高效液相色谱法测定红景天根中红景天甙的含量

建立了一种高效液相色谱法测定红景天根中红景天甙的含量。色谱柱为Hypersil—C18（5μm,150mm×4．6mm）,甲醇-水为流动相,梯度洗脱,柱温25℃,在250nm波长处检测。研究结果表明：红景天甙的检测限为50μg/L,线性范围为4—40mg／L,回归方程为Y=5．6348X-4．0931,r=0．9996,加样回收率为98．05％。方法操作简便、快速、准确。     

Preparative Isolation and Purification of Hydroxyanthraquinones from Rheum tanguticum Maxim. on Normal Phase Silica Gel: Using a Flash Master Personal System

Abstract

A flash chromatography method for preparative separation and purification of five hydroxyanthraquinones from the Chinese medicinal herb Rheum tanguticum Maxim. ex Balf. was developed by using Flash Master Personal⁺ systems. The purities of the products, chrysophanol, physcion, emodin, aloe‐emodin, and rhein were all over 90%, determined by high performance liquid chromatography (HPLC). Their structures were ascertained by EI‐MS, ¹H‐ and ¹³C‐NMR data, and by co‐TLC and HPLC with the authentic samples available in our laboratory.     

高效液相色谱法同时测定保健食品中低聚果糖和低聚木糖

目的 建立高效液相色谱法同时测定保健食品中低聚果糖(包括蔗果三糖、蔗果四糖及蔗果五糖)和低聚木糖（包括木二糖、木三糖、木四糖、木五糖、木六糖及木七糖）的含量。方法 采用键合有酰胺官能团杂化填料的色谱柱,以乙腈和水为流动相,利用亲水保留色谱机制（HILIC）实现对低聚果糖和低聚木糖各单体的有效分离,结合示差检测以外标法定量。该方法同时利用木糖对低聚木糖各单体转换系数进行定量。结果 低聚果糖和低聚木糖各单体线性关系良好,相关系数均大于0.998,平均加标回收率为95%以上,具有较高的准确度和良好的重现性。结论 高效液相色谱法由于采用木糖对照品转换定量低聚木糖含量,减少低聚木糖各单体标准品在日常工作中的使用量,进而降低检测成本。该方法经济可靠,测定结果准确,适合于添加有低聚果糖和低聚木糖的功能性产品检测。     

Biochemical and Pharmacological Characteristics of Conjugated Catecholamines in the Rat Brain

Mass-fragmentographic methods are described that enable the simultaneous measurement of total, free, and conjugated catecholamines in brain tissues. These methods were used to assess the distribution, kinetics, and pharmacological characteristics of total, free, and conjugated catecholamines in the hypothalamus, caudate nucleus, hippocampus, and septum. Conjugated norepi-nephrine (NE) represents ?20% of total NE in the hypothalamus, septum, and hippocampus, whereas the percentage is ? 50% in the caudate nucleus. The percentages of conjugated dopamine (DA) in these brain areas are consistently less than those of NE (?13%). Although in the hypothalamus the steady-state concentrations of total, free, and conjugated NE are over four times higher than those of the corresponding total, free, and conjugated DA, the turnover rates of this DA are comparable with those of the corresponding NE. Further, the ratios of conjugated NE or DA turnover rates to those of the total amines are higher than the corresponding ratios of their steady-state concentrations. Treatments with pargyline (75 mg/kg, i.p.; rats killed 30 and 60 min later) failed to change the contents of conjugated catecholamines in the hypothalamus and the caudate nucleus significantly. Pharmacological manipulation with a number of proto-typic drugs revealed that although the assay of conjugated catecholamines might shed additional light on the effects of drugs on central catecholamines, the assessment of total or free amines are on the whole equally informative. In conclusion, a detailed assessment of brain conjugated catecholamines is reported. The information provided, fills a gap in our knowledge that has up to now not been adequately addressed.     

Fluorescence Detection of Carbon-Centered Radicals in Aqueous Solution

A simple, highly sensitive method for the simultaneous determination of arrays of carbon-centered radicals in aqueous systems is described. Radicals are efficiently trapped by an amino-nitroxide to form stable products which are then reacted with fluorescamine to produce highly fluorescent adducts. The adducts are easily separated by reversed-phase high performance liquid chromatography. The detection limit for individual radical adducts (0.5 to 2nM) is two to three orders of magnitude lower than those of current methods employing electron paramagnetic resonance detection. Results on the photolysis of ketones and z-keto acids demonstrate the potential of this technique. This approach should be widely applicable to the study of radical processes in biological and chemical systems.     

Trp7,Leu8]LH-RH in reptilian brain

Luteinizing hormone-releasing hormone (LH-RH) immunoreactive peptides in acetic acid extracts of lizard (Cordylis nigra) brain were studied by high performance liquid chromatography (HPLC) and radioimmunoassay with region-specific antisera. Four different LH-RH immunoreactive peptides were detected. The major form co-eluted with salmon brain LH-RH, [Trp7,Leu8]LH-RH, in a cation exchange and three reverse phase HPLC systems which were specifically designed to separate a range of LH-RH analogues. The interaction of this major LH-RH immunoreactive peptide with a number of antisera directed against different regions of mammalian, chicken and salmon LH-RH was similar to the relative interaction of [Trp7,Leu8]LH-RH with these antisera. These data strongly indicate that the major form of lizard brain LH-RH is identical to salmon brain LH-RH [( Trp7,Leu8]LH-RH). The three additional molecular forms of immunoreactive LH-RH in lizard brain appear to differ from mammalian LH-RH in the middle to C-terminal region of the molecule.     

反相高效液相色谱法测定柳枝皮提取物中水杨苷的含量

建立了一种反相高效液相色谱法测定柳枝皮提取物中水杨苷的含量.色谱柱为Shim-pack CLC-ODS(6.0 mm i.d×150 mm,5 μm),流动相为甲醇-0.01 mol/L磷酸二氢钾水溶液(体积比为20∶80),在213 nm波长处检测.研究结果表明:水杨苷的检测限为25 ng,线性范围为8.00～80.00 mg/L,回归方程为A=0.0642C(241.2501(r=0.999 5),加样平均回收率为94.32%.方法操作简便、快速、准确.     

Extraction, characterization of polysaccharides from Morinda officinalis and its antioxidant activities

Morinda officinalis How (Rubiaceae) is widely used for medicinal purposes in China, Korea and Japan. Polysaccharides have also been determined and recently were shown to have protective effect against bone loss. A large number of polysaccharides present in the M. officinalis were successively extracted with hot water after preliminary treatments. The UV scan was used to analyse quality and purity of the polysaccharides from M. officinalis (MOP). Result indicated that had a better purity and quality and was free of proteins. HPLC showed that MOP mainly consisted of glucose (retention time, 8.691) and fructose (retention time, 9.245) with a molar ratio of 1.29:2.71. On the basis of analysis of chemical components, antioxidant activity of MOP was evaluated. The obtained results showed that MOP supplementation resulted in (a) increased antioxidant enzyme activities, and (b) decreased MDA level in rats.     

液相色谱法定量检测老年人血浆游离脂肪酸

目的：分析老年人群空腹血浆游离脂肪酸水平及构成特点。方法：采用高效液相色谱（highperformanceliquidchromatog．raphy,HPLC）,检测149名60—104岁的健康老年人空腹血浆游离脂肪酸（FreeFattyacids,FFAs）的水平,包括月桂酸（C12：0）、二十碳五烯酸（C20：5）、豆蔻酸（C14：0）、软油酸（C16：1）、花生四烯酸（C20：4）、亚油酸（c18：2）、软脂酸（C16：0）、油酸（C18：1）和硬脂酸（C18：0）。结果：血浆FFA水平呈偏态分布;含量占血浆总FFA10％以上的单个FFA有3种,分别为：C16：0,C18：1和C18：2,共占总FFA的80％。结论：C16：0,C18：1和C18：2为血浆总FFA的主要组分,可体现血浆总FFA水平,并给出了健康老年人群的血浆总FFA及9种亚组分的均值、四分位数及中位数水平。     

Peptides in the hemolymph of Hermetia illucens larvae completely inhibit the growth of Klebsiella pneumonia in vitro and in vivo

Extensive use of antibiotics has caused the microbial resistance to rise drastically within the last few decades, and new approaches are therefore needed to develop effective antibacterial substances. In this study, we identified peptide in the hemolymph of Hermetia illucens larvae using reverse-phase chromatography, HPLC and Nano-LC-ESI-MS/MS system. We investigated the antibacterial effect of HP/F9 peptides against Klebsiella pneumoniae in vitro and in vivo. The peptide effectively inhibited the growth of K. pneumoniae in vitro and completely removed K. pneumoniae from the lungs of mice. Importantly, peptides (22,000 Da, HP/F9) successfully reduced lung inflammation upon K. pneumoniae infection. These results indicate that the HP/F9 peptide from H. illucens larva can effectively protect the mouse from K. pneumoniae infection. HP/F9 could be a new candidate for the development of effective antibacterial substance.     

A rapid high performance liquid chromatographic method for the separation of the alkaloid precursor L-tyrosine and six tetrahydroisoquinoline alkaloids of Papaver somniferum

A high performance liquid chromatographic (HPLC) method was developed for the qualitative and quantitative determination of L-tyrosine and six common tetrahydroisoquinoline alkaloids (papaverine, noscapine, sanguinarine, morphine, codeine and thebaine) of Papaver somniferum. The reversed phase HPLC method yields baseline separation of the alkaloids in 20 min and is achieved using a simple H₂O: MeOH linear gradient. Silanol effects commonly associated with the separation of such strongly basic compounds were minimized by the addition of the amine modifier, triethylamine, to the mobile phase.     

A high performance liquid chromatography assay for the rapid analysis of the subunit content of concanavalin A

A high performance liquid chromatography system is described which provides a rapid and convenient assay for the relative amounts of intact (26 000 dalton) and fragmented (14 000 and 12 000 dalton) subunits present in preparations of concanavalin A. Analyses were performed on an HPLC size exlusions column using either 8 M urea or 6 M guanidine hydrochloride as denaturing eluents. The efficiency and resolving power of this technique were confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. This HPLC assay facilitated the monitoring of the purification of concanavalin A to prepare a homogeneous preparation necessary for its biological evaluation.