芯片式流通池顺序注射可更新表面反射光谱法用于酶反应检测

将芯片式流通池顺序注射可更新表面反射光谱法用于酶反应检测。HRP催化H2O2氧化BPR底物的反应用于对H2O2的检测。此反应体系与葡萄糖氧化酶联用，用于对血清中葡萄糖的检测。     

淫羊藿根与叶活性成分的分析和比较

采用细胞膜色谱法（ＣＭＣ）筛选，并结合离体药理实验确定主要活性成分，利用高效液相色谱法分析比较了淫羊藿根与叶中的活性成分及其差异性．色谱条件为Ｋｒｏｍａｓｉｌ ＯＤＳ 柱（１５０ ｍｍ× ４．６ ｍｍ．Ｉ．Ｄ ）流动相甲醇－水（７０：３０，Ｖ：Ｖ）；检测波长２７０ｎｍ。筛选发现淫羊藿根中的两个有效成分ＹＹＨ－２１４和ＹＹＨ－２１６对血管有较强的舒张作用，表明活性成分在ＣＭＣ模型体系中的保留特性与药理作用之间存在良好的相关性。在此色谱条件下淫羊藿叶未检测到这两种活性成分．     

Expression and Characterization of Catalytic Domain of T Cell Protein Tyrosine Phosphatase（△TC-PTP） —— Immunohistochemical Study of △TC-PTP Expression in Non-small Cell Lung Carcinomas

This study objective was to express and characterize the catalytic domain of the human T cell protein tyrosine phosphatase（△TC-PTP） and to study immunohistochemically the expression of △TC-PTP in human non-small cell lung cancers. △TC-PTP gene was PCR amplified with the cDNA of human TC-PTP as template, and cloned into the pT7 expression vector. The recombinant pT7-△TC-PTP was expressed in E. coli Rosetta （ DE3 ） host cells and puri- fied. The enzymatic characteristics of △TC-PTP including enzyme activity and kinetics assay were measured. The antiserum was prepared by immunizing rabbit with the purified recombinant △TC-PTP. Rabbit polyclonal antibody against △TC-PTP was purified by PVDF immobilized antigen affinity chromatography. Immunohistochemical staining of lung cancer tissues was performed with antibody against △TC-PTP protein. △TC-PTP gene was correctly cloned, expressed, and purified. The recombinant △TC-PTP had a highly catalytic activity of PTPase. Squamous cell lung carcinoma showed a significantly higher expression rate of △TC-PTP （76. 92%, 10/13 ） than adenocarcinoma （57.14%, 4/7） and normal lung tissue（20%, 1/5 ）. This study represents the first demonstration that △TC-PTP is highly expressed in human squamous cell lung carcinomas. In addition, this study provides an important basis for further studying the biological function of TC-PTP and its relationship with lung carcinomas and other diseases.     

Mass transport in gas channels of electrochemical cells with a solid-oxide electrolyte: Allowing for the electrode reaction rates in numerical calculations

The concentration fields, Nusselt number distributions along the electrode, and ratios of concentrations of electrochemically active components at the entrance into and exit out of an electrochemical cell are determined by numerical integration of the convective-diffusion equation for a broad range of rate constants of electrode reactions, Peclet numbers, and geometrical parameters of channels. Three regions of parameter values are revealed. At low reaction rates (K _l < 0.5), mass transfer is completely determined by electrode kinetics; at high rates (K _l > 20), it is completely determined by the diffusion in the gas phase; and in the intermediate region of values of K _l it is necessary to allow for both the diffusion processes and the electrode reactions.Translated from Elektrokhimiya, Vol. 41, No. 3, 2005, pp. 317–324.Original Russian Text Copyright © 2005 by Ezin, Somov.     

Study on Extraction Process of Root of Henry Wood Betony Polysaccharides and Their Antitumor Activity against S180

We optimized the hot water extraction of polysaccharides from the root of Henry wood betony (RHWPs) using a uniform test and explored their anti-tumor activities in vitro and in vivo. The optimal extraction conditions were as follows: 40 min extraction time, liquid/solid ratio 30 mL/g, 100 min soaking time, two extraction cycles, 100% ethanol concentration, and extraction temperature of 80 °C. The molecular weight distribution of RHWPs with MWs was 228,600 g/mol and 5001 g/mol. The IR spectrum further indicated that RHWPs are acidic polysaccharides containing pyranose and furan rings. The main monosaccharides found in RHWPs were mannose, ribose, l-rhamnose monohydrate, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose, and fucose. RHWPs inhibited the proliferation of S180 tumor cells and induced apoptosis in vitro. Oral administration of RHWPs to tumor-bearing mice significantly inhibited the growth of the S180 xenografts, accelerated apoptosis in tumor cells, and expanded the necrotic regions. Furthermore, RHWPs also markedly increased the levels of TNF-α, IFN-γ, and IL-2 in the sera of tumor-bearing mice, and activated immune cells such as lymphocytes, NK cells, and macrophages, thereby inducing tumor cell apoptosis. Taken together, RHWPs are a promising anti-tumor agent that ought to be explored further.     

Cellulose-precursor synthesis of nanocrystalline Ce<Subscript>0.8</Subscript>Gd<Subscript>0.2</Subscript>O<Subscript>2−δ</Subscript> for SOFC anodes

Developments of intermediate-temperature solid oxide fuel cells (IT SOFCs) require novel anode materials with a high electrochemical activity at 800–1070 K. The polarization of cermet anodes, made of nickel, ceria and yttria-stabilized zirconia (YSZ) and applied onto a YSZ solid electrolyte, can be significantly reduced by catalytically active ceria additions, the relative role of which increases with decreasing temperature. Further improvement is observed when using Ce_0.8Gd_0.2O_2– (CGO) having a high oxygen ionic conductivity instead of undoped ceria, owing to enlargement of the electrochemical reaction zone. Nanocrystalline CGO powders with grain sizes of 8–35 nm were thus synthesized via the cellulose-precursor technique and introduced into Ni–CGO–YSZ cermets, and tested in contact with a (La_0.9Sr_0.1)_0.98Ga_0.8Mg_0.2O_3– (LSGM) electrolyte at 873–1073 K. The results showed that the anode performance can be enhanced by additional surface activation, in particular by impregnation with a Ce-containing solution, and also by incorporation of YSZ, which probably acts as a cermet-stabilizing component. The overpotential of the surface-modified Ni–CGO (25 wt%–75 wt%) anode in a 10% H₂/90% N₂ atmosphere was approximately 110 mV at 1073 K with a current density of 200 mA/cm².Presented at the OSSEP Workshop Ionic and Mixed Conductors: Methods and Processes, Aveiro, Portugal, 10–12 April 2003     

Effects of coupling agents on mechanical and morphological behavior of the PP/HDPE blend with two different CaCO3

The main purpose of incorporating fillers, such as calcium carbonate, into blends of polyolefins is to decrease costs and change tensile and impact properties. Structural differences between both components give rise to the formation of large filler agglomerates in the polymer matrix, which influence the mechanical response of the material. Therefore, the coupling agents of the Lica 12 type at various concentrations was used to facilitate the link between filler and matrix (the latter consisting of PP/HDPE 80/20 wt). Filler was added to the PP/HDPE blend at a 30 wt.% concentration. Two types of calcium carbonate (CaCO₃) were used. These have different average sizes (3.0 and 1.8 μm) which were determined by means of laser diffraction techniques. In addition other coupling agents of the titanate type, such as Lica 09, Lica 01, zirconates ZN 12, and a 1:1 mixture of Lica 12 and Lica 01, were used. This study clearly demonstrated that the addition of the coupling agent to CaCO₃ modifies the mechanical properties of the PP/HDPE/CaCO₃ composites. Values of the mechanical properties indicate that due to its characteristics, each coupling agent gives rise to increases in a particular mechanical property. In the case of Lica 01 an increase was verified in Young’s modulus at 0.7 wt.% and in elongation at break at both concentrations (0.3 and 0.7 wt.%), whereas ZN 12 brought about an increase in elongation at break. The 1:1 mixture of Lica 12 and Lica 01 caused impact resistance of the blend of PP/HDPE with CaCO₃ to increase considerably.     

Forward-scattering degenerate four-wave mixing as a potential laser-based absorption detection method in liquid separation systems: Coupling to conventional-size liquid chromatography

An explorative study on the compatibility of liquid separation systems, such as (micro) liquid chromatography (LC) and capillary electrophoresis (CE), and forward-scattering degenerate four-wave mixing (F-D4WM) as a detection method is presented. F-D4WM is a laser-based technique showing some analogy with holographic spectroscopy: a signal on a theoretical dark background is observed as a result of light absorption by an analyte. Parameters considered are solvent composition focussing on acetonitrile, methanol and water; mobile phases in LC and CE), detector cell construction, and influences of laser beam powers. A specially designed detector cell has been developed to meet the Brewster condition, both at the air-quartz and the quartz-liquid boundaries. For practical reasons, the tested cell has an optical pathlength of 1 mm; reduction to 100 μm is required to apply the cell in microseparations. The F-D4WM technique has been involved for detection in a conventional-size, reversed-phase LC separation of 1- and 2-aminoanthraquinones. The detection limit obtained (for the 1 mm cell) is 2 × 10⁻⁵ absorbance units. The experiments indicate that further reduction of background deserves explicit attention.     

Mammalian cell growth studiedin situ by fourier transform infrared spectroscopy

Fourier transform infrared techniques were used to monitor mammalian cell growth plated on attenuated total reflection (ATR) crystals. Consistently, the growth kinetics plots generated from the obtained spectra demonstrated a sigmoidal curve representing a sequence of slow, rapid, then tapering cell growth which correlated well with non-spectral cell growth determinations. Significant advantages over traditional methods of measuring cell growth kinetics are demonstrated. The technique has promising potential to be used to study events in areas such as toxicology and cell biology.     

A novel class of amide-derived air-stable P,O-ligands for Suzuki cross-coupling at low catalyst loading

The benzamide-derived P,O-ligands efficiently promoted the Pd-catalyzed Suzuki cross-coupling reactions of aryl bromides with phenylboronic acid at 0.01 mol % of Pd loading at 60-80 °C to form biaryls in excellent yields. A sterically hindered arylboronic acid gave a quantitative yield of the coupling product at 110 °C with 1 mol % Pd.