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951.
Carbon monoxide suppresses arteriosclerotic lesions associated with chronic graft rejection and with balloon injury 总被引:27,自引:0,他引:27
Otterbein LE Zuckerbraun BS Haga M Liu F Song R Usheva A Stachulak C Bodyak N Smith RN Csizmadia E Tyagi S Akamatsu Y Flavell RJ Billiar TR Tzeng E Bach FH Choi AM Soares MP 《Nature medicine》2003,9(2):183-190
Carbon monoxide (CO), one of the products of heme oxygenase action on heme, prevents arteriosclerotic lesions that occur following aorta transplantation; pre-exposure to 250 parts per million of CO for 1 hour before injury suppresses stenosis after carotid balloon injury in rats as well as in mice. The protective effect of CO is associated with a profound inhibition of graft leukocyte infiltration/activation as well as with inhibition of smooth muscle cell proliferation. The anti-proliferative effect of CO in vitro requires the activation of guanylate cyclase, the generation of cGMP, the activation of p38 mitogen-activated protein kinases and the expression of the cell cycle inhibitor p21Cip1. These findings demonstrate a protective role for CO in vascular injury and support its use as a therapeutic agent. 相似文献
952.
Cloning and sequence analysis of endoglucanase genes from an industrial fungus, Aspergillus kawachii
Three endoglucanase genes (cel5A, cel5B, and cel61A) were cloned from an industrial fungus, Aspergillus kawachii. Yeasts transformed with these cDNAs showed endoglucanase activity in medium. Cel5A and Cel61A contained a type 1 cellulose-binding domain (CBD1) at the C-terminus of the enzyme. The putative catalytic regions of Cel5A and Cel5B showed homology with various endoglucanases belonging glycosyl hydrolase family 5 (GH5). Cel5B showed high homology with Cel5A in catalytic region, but it lacked CBD1 and linker. The cel5A contained four introns, whereas cel5B contained five introns. The putative catalytic region of Cel61A showed homology with enzymes belonging to GH61. The cel61A contained no introns. 相似文献
953.
Yamanoue M Ueda S Ohashi A Yoshimura Y Norioka S 《Bioscience, biotechnology, and biochemistry》2003,67(3):563-569
In order to clarify the position where paratropomyosin binds to connectin in the A-I junction region of a sarcomere, chicken beta-connectin was digested by Staphylococcus aureus V8 protease under denaturing conditions and the digested peptides were electrophoretically separated. Five peptides, 150-kDa, 100-kDa, 70-kDa, and 43-kDa fragments, were simultaneously detected by biotinylated paratropomyosin and an anti-connectin monoclonal antibody. The N-terminal sequence of the 43-kDa fragment was found to be YQFRVYAVNK, similar to the sequence of 7556-7565 amino acids in the I51 fibronectin type 3 domain that was located at the A-I junction region of human cardiac titin/connectin. Therefore, we propose that paratropomyosin binds to the 43-kDa fragment from beta-connectin at the A-I junction region in both living muscle and in muscle immediately postmortem, and the N-terminus of the 43-kDa fragment is localized in the I51 domain. 相似文献
954.
Stereocontrolled total syntheses of the (2S,3R)- and (2R,3S)-isomers of the non-chlorinated analog of cyanobacterin, a potent photosynthesis inhibitor, were achieved. Since both the (2R,3R)- and (2S,3S)-isomers of this compound had been previously synthesized from the same starting material, a systematic strategy for the synthesis of all stereoisomers could be established. 相似文献
955.
Tohno Y Tohno S Satoh H Minami T Moriwake Y Azuma C Ohnishi Y 《Biological trace element research》2002,88(3):203-213
To elucidate compositional changes of the mitral valve with aging, the authors investigated the relationships among element
contents in the mitral valves. The subjects consisted of 10 men and 15 women, ranging in age from 65 to 102 yr. After the
ordinary dissection, mitral valves, lower parts of the interventricular septa, and terminal crests containing the sinoatrial
nodes were resected and the element contents were determined by inductively coupled plasma-atomic emission spectrometry. The
interventricular septa and sinoatrial nodes were used to compare with the mitral valves. With regard to the mitral valve,
it was found that extremely significant correlations were found among the contents of Ca, P, Mg, and Na, but no significant
correlations were found between the contents of S and elements such as Ca, P, or Mg. Regarding the interventricular septum,
it was found that an extremely significant correlation was found between P and S contents; very significant correlations were
found between Ca and Mg contents and between Mg and S contents; and a significant correlation was found between P and Mg contents.
However, no significant correlation was found between Ca and P contents in the interventricular septa. In the terminal crest
containing the sinoatrial node, significant correlations were found among the contents of Ca, P, Mg, and S. The present study
revealed that with regard to the relationships among element contents, the compositional change of the mitral valve was intermediate
between those of the thoracic aorta and the interventricular septum. 相似文献
956.
Usuda K Kono K Dote T Shimizu H Tominaga M Koizumi C Nakase E Toshina Y Iwai J Kawasaki T Akashi M 《Biological trace element research》2002,86(1):45-54
In previous article, we showed a log-normal distribution of boron and lithium in human urine. This type of distribution is
common in both biological and nonbiological applications. It can be observed when the effects of many independent variables
are combined, each of which having any underlying distribution.
Although elemental excretion depends on many variables, the one-compartment open model following a first-order process can
be used to explain the elimination of elements. The rate of excretion is proportional to the amount present of any given element;
that is, the same percentage of an existing element is eliminated per unit time, and the element concentration is represented
by a deterministic negative power function of time in the elimination time-course.
Sampling is of a stochastic nature, so the dataset of time variables in the elimination phase when the sample was obtained
is expected to show Normal distribution. The time variable appears as an exponent of the power function, so a concentration
histogram is that of an exponential transformation of Normally distributed time. This is the reason why the element concentration
shows a log-normal distribution.
The distribution is determined not by the element concentration itself, but by the time variable that defines the pharmacokinetic
equation. 相似文献
957.
Molecular mechanisms underlying differential contribution of CD28 versus non-CD28 costimulatory molecules to IL-2 promoter activation 总被引:5,自引:0,他引:5
958.
A lectin was isolated from an ascomycete mushroom, Ciborinia camelliae which was specific to N-acetyl-D-galactosamine. On SDS-polyacrylamide gel electrophoresis; this lectin gave a single band of approximately 17-kDa in the presence of 2-mercaptoethanol, but formed dimers, trimers and tetramers in its absence. Amino acid analysis revealed the lectin contained two cysteines and no methionine. The N-terminal sequence was determined up to residue 21, and no homologous proteins including other ascomycete lectins were found. 相似文献
959.
Numerous troponin T (TnT) isoforms are produced by alternative splicing from three genes characteristic of cardiac, fast skeletal, and slow skeletal muscles. Apart from the developmental transition of fast skeletal muscle TnT isoforms, switching of TnT expression during muscle development is poorly understood. In this study, we investigated precisely and comprehensively developmental changes in chicken cardiac and slow skeletal muscle TnT isoforms by two-dimensional gel electrophoresis and immunoblotting with specific antisera. Four major isoforms composed of two each of higher and lower molecular weights were found in cardiac TnT (cTnT). Expression of cTnT changed from high- to low-molecular-weight isoforms during cardiac muscle development. On the other hand, such a transition was not found and only high-molecular-weight isoforms were expressed in the early stages of chicken skeletal muscle development. Two major and three minor isoforms of slow skeletal muscle TnT (sTnT), three of which were newly found in this study, were expressed in chicken skeletal muscles. The major sTnT isoforms were commonly detected throughout development in slow and mixed skeletal muscles, and at developmental stages until hatching-out in fast skeletal muscles. The expression of minor sTnT isoforms varied from muscle to muscle and during development. 相似文献
960.
Yamamoto YY Tsuhara Y Gohda K Suzuki K Matsui M 《The Plant journal : for cell and molecular biology》2003,35(2):273-283
Experiments with gene-trap vectors containing the firefly luciferase (LUC) reporter genes were carried out with the aim of analyzing functions of the Arabidopsis genome. Studies with protein fusion-type trap vectors as well as an internal ribosome entry site (IRES)-assisted non-fusion-type vector revealed that both types of vectors were suitable for gene trapping in Arabidopsis, although there were some differences in trapping efficiencies. The established trap lines were subjected to analyses for light responses, demonstrating the powerful and unique applications of a LUC-trapping system. A systematic survey of the insertion sites of the T-DNAs in LUC-expressing lines revealed 12-41% gene-trapping efficiencies depending on the vector. We demonstrate that the LUC-trapping system provides a unique system with which to monitor temporal expression of plant genes. 相似文献