Zhonghua Yi Xue Za Zhi
August 2007
Objectives: To explore the possibility and clinical application value of fecal lactoferrin as a marker of the activity of ulcerative colitis (UC).
Methods: Specimens of feces were collected from 66 UC patients and 20 healthy persons or irritable bowel syndrome patients. ELISA was used to measure the concentration of lactoferrin in feces, and CRP and ESR were also measured.
Whispering-gallery modes (WGMs) in a zeolite cylinder have been effectively coupled with a low-loss fiber taper. The fiber transmission spectrum directly shows the WGM distribution, which agrees well with the theoretical prediction based on geometric optics. Due to other scattering and absorbing mechanisms, the measured quality factors of the WGMs are limited to approximately 800.
View Article and Find Full Text PDFMicroporous carbon (MC) with a high surface area has been prepared from cornstalks through carbonization and KOH activation. The surface area of the obtained product varies to some extent but the pore size of the material remains within the micropore region as the concentration of KOH activating agent is increased. The MC we prepared exhibits H2 adsorption capacities up to 4.
View Article and Find Full Text PDFSize-dependent 3D superlattices have been fabricated from ZnO nanocrystals capped with ionic liquid components; on the basis of X-ray diffraction, two packing modes, that is, hexagonal and face-centered cubic close packings, have been discovered for the superlattices consisting of the ZnO nanocrystals as building blocks.
View Article and Find Full Text PDFHighly monodisperse submicrometer CdS colloidal spheres (CSCS) with a controllable and tunable size (between 80 and 500 nm) have been synthesized through a facile solvothermal technique. Owing to the controllability of the reaction process, the growth mechanism of the colloidal spheres has been elucidated in detail. The whole growth process can be summarized as homogenous and slow nucleation of nanocrystals, formation of "cores" through 3D-oriented attachment of nanocrystals, and further surface-induced growth to monodisperse colloidal spheres through in situ formation and random attachment of additional nanocrystals.
View Article and Find Full Text PDFA series of Pb(II) coordination polymers [Pb(ndc)(dpp)] (1), [Pb(ndc)(ptcp)].0.5 H2O (2), [Pb(ndc)(dppz)] (3), [Pb(ndc)(tcpn)(2)] (4), [Pb2(ndc)2(tcpp)] (5), [Pb(Hndc)2].
View Article and Find Full Text PDFGeneral anesthetics, including etomidate, act by binding to and enhancing the function of GABA type A receptors (GABA(A)Rs), which mediate inhibitory neurotransmission in the brain. Here, we used a radiolabeled, photoreactive etomidate analog ([(3)H]azietomidate), which retains anesthetic potency in vivo and enhances GABA(A)R function in vitro, to identify directly, for the first time, amino acids that contribute to a GABA(A)R anesthetic binding site. For GABA(A)Rs purified by affinity chromatography from detergent extracts of bovine cortex, [(3)H]azietomidate photoincorporation was increased by GABA and inhibited by etomidate in a concentration-dependent manner (IC(50) = 30 microm).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2006
Cecropin A1 (CA), first found in the diapause pupa of Hyalophora cecropia, is an alpha-helix antimicrobial peptide. It has suppressive effect on several strains of bacteria but its effect is moderate. Therefore it is imperative to find new peptides of high lethality to pathogenic bacteria.
View Article and Find Full Text PDFTo locate the binding sites of general anesthetics on ligand-gated ion channels, two derivatives of the intravenous general anesthetic etomidate (2-ethyl 1-(phenylethyl)-1H-imidazole-5-carboxylate), in which the 2-ethyl group has been replaced by photoactivable groups based on either aryl diazirine or benzophenone chemistry, have been synthesized and characterized pharmacologically. TDBzl-etomidate (4-[3-(trifluoromethyl)-3H-diazirin-3-yl]benzyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylate) and BzBzl-etomidate (4-benzoylbenzyl-1-(1-phenylethyl)-1H-imidazole-5-carboxylate are both potent general anesthetics with half-effective anesthetic concentrations of 700 and 220 nM, respectively. Both agents resembled etomidate in enhancing currents elicited by low concentrations of GABA on heterologously expressed GABAA receptors and in shifting the GABA concentration-response curve to lower concentrations.
View Article and Find Full Text PDFLayered double hydroxide Cd(1)(-)(x)()Al(x)()(OH)(2)(DS)(x)().3.0H(2)O (CdAlDS) and a related hydroxide salt compound Cd(2)(OH)(3)(DS).
View Article and Find Full Text PDFFour homochiral porous lanthanide phosphonates, [Ln(H2L)3].2H2O, (H3L = (S)-HO3PCH2-NHC4H7-CO2H, Ln = Tb (1), Dy (2), Eu (3), Gd (4)), have been synthesized under hydrothermal conditions. These compounds are isostructural, and they possess a 3D supramolecular framework built up from 1D triple-strand helical chains.
View Article and Find Full Text PDFFour new rare-earth compounds, [Eu(NDC)1.5(DMF)2] (1), [Nd2(NDC)3(DMF)4].H2O (2), [La2(NDC)3(DMF)4].
View Article and Find Full Text PDFZhonghua Zhong Liu Za Zhi
June 2005
Three new 3d-4f heterometallic coordination polymers, [Ln(2)(H(2)O)(4)M(2)(H(2)O)(2)(QA)(5)].nH(2)O (H(2)QA = quinolinic acid; Ln = Gd, M = Ni, n = 7 (1); Ln = Gd, M = Co, n = 6.5 (2); Ln = Dy, M = Co, n = 6.
View Article and Find Full Text PDFBeijing Da Xue Xue Bao Yi Xue Ban
June 2005
Objective: To investigate the effect of tumor specific antigen of HCA520 on the proliferation of HEK293 cells and to obtain some functional implications for HCA520.
Methods: MTT assay was performed with HEK293 stable cell lines transfected with pcDNA3-HCA520-flag construct. Cytokines probably involved in HCA520 enhanced proliferation were screened by RT-PCR, and effect of these cytokines on the HEK293 cell proliferation was further confirmed by MTT assay.
A mathematical model is proposed for predicting the copolymer composition of the microbially synthesized polyhydroxyalkanoate (PHA) copolymers. Based on the biochemical reactions involved in the precursor formation and polymerization pathways, the model correlates the copolymer composition with the cultivation conditions, the enzyme levels and selectivity, and the metabolic pathways. It suggests the following points: (1) in the case of a sole carbon source, the copolymer composition depends mainly on the topology of the metabolic pathways and the selectivity of both the enzymes involved in the precursor formation and the polymerization route; (2) the copolymer composition can be varied in a wide range via alteration of the flux ratio of different types of monomers channeled from two or more independent and simultaneous pathways; (3) the enzymes which should be over-expressed or inhibited to obtain the desired copolymer composition can be predicted.
View Article and Find Full Text PDFSyncollin was first demonstrated to be a protein capable of affecting granule fusion in a cell-free system, but later studies revealed its luminal localization in zymogen granules. To determine its possible role in exocytosis in the intact cell, syncollin and a truncated form of the protein (lacking the N-terminal hydrophobic domain) were stably transfected in insulin-secreting INS-1 cells since these well-studied exocytotic cells appear not to express the protein per se. Studies by subcellular fractionation analysis, double immunofluorescence staining, and electron microscopy examination revealed that transfection of syncollin produced strong signals in the insulin secretory granules, whereas the product from transfecting the truncated syncollin was predominantly associated with the Golgi apparatus and to a lesser degree with the endoplasmic reticulum.
View Article and Find Full Text PDFFor the development of specific immunological assays, the binding of a specific antibody (Ab) to the target antigen (Ag) has to be relatively strong. In this study, we have utilized affinity capillary electrophoresis (ACE), a form of capillary zone electrophoresis (CZE) to determine the binding constant (Kb) of specific Abs against bovine serum albumin (BSA) and the healthy prion protein (PrPc), in buffer solutions at fixed pHs, approximating in vivo conditions. We have also utilized capillary isoelectric focusing (cIEF) to determine the complexity and recognition of the various isoforms of PrPc Abs towards their Ag, PrPc.
View Article and Find Full Text PDFTowards a goal of detecting scaled-up DNA adducts as altered deoxynucleotides by mass spectrometry, we have set up a practical and general method for isolating DNA-derived deoxyribonucleoside-5'-monophosphates devoid of ribonucleotides starting with a 1 g sample of mammalian tissue. The method is practical because costs have been minimized, and it is general because it can be applied to a more difficult sample such as mouse skin or non-fresh calf liver. The procedure, consisting of a series of steps that were largely gleaned and tuned from prior literature, proceeds as follows: (1) homogenize the tissue in sodium dodecyl sulfate; (2) digest with ribonuclease A, ribonuclease TI, alpha-amylase and proteinase K; (3) partition between water and phenol; (4) precipitate the DNA with ethanol followed by redissolving and dialysis; and (5) digest with nuclease P1 and phosphodiesterase I followed by ultrafiltration and boric acid gel chromatography.
View Article and Find Full Text PDFLin Chuang Er Bi Yan Hou Ke Za Zhi
November 2002
Objective: To chronologically evaluate the changes in both sides of thyroarytenoid (TA) muscles. when one side of recurrent laryngeal nerve (RLN) was cut off.
Method: In 7 adult mongrel dogs, 2 dogs for control and the other 5 dogs for the following experiment: a 2 cm segment of right RLN was excised under intraperitoneal sedation.
GABA(A) receptors have structural and functional homology with a super-family of cys-loop ligand-gated ion channel receptors including the nicotinic acetylcholine receptors. Amino acid residues involved in ligand-binding pockets are homologous among super-family members, leading to the multiple-loop model of binding sites situated at subunit interfaces, validated by structural studies on the nicotinic acetylcholine receptor and water-soluble snail acetylcholine binding protein. This article will briefly review the literature on the agonist binding sites on the receptor super-family, and then describe the current situation for attempts to identify sites for allosteric modulators on the GABA(A) receptors.
View Article and Find Full Text PDFA uranium-nickel-organic hybrid compound with micropores has been assembled from a hydrothermal system, and this compound exhibits photocatalytic activities for the degradation of methyl blue as a model pollutant.
View Article and Find Full Text PDFPlatelet-endothelial cell adhesion molecule-1 (PECAM-1) is an integral component of endothelial cells and has been implicated in the transendothelial migration (TEM) of circulating leukocytes mediated by its 1st and 2nd extracellular immunoglobulin (Ig)-like domains and regulation of intracellular Ca(2+) homeostasis with its 6th domain. Up-to-date, little is known about the role of the 5th extracellular (Ig)-like domain. We have discovered a novel human PECAM-1 transcript missing the entire 7th exon, which encodes the 5th extracellular (Ig)-like domain of PECAM-1.
View Article and Find Full Text PDFPeripheral tissue injury-induced central sensitization may result from the altered biochemical properties of spinal dorsal horn. However, peripheral nerve injury-induced modification of genes in the dorsal horn remains largely unknown. Here we identified strong changes of 14 channels, 25 receptors and 42 signal transduction related molecules in Sprague-Dawley rat dorsal spinal cord 14 days after peripheral axotomy by cDNA microarray.
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