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31.
The different physiological roles of interleukin-1alpha (IL-1alpha) and interleukin-1beta (IL-1beta) are not well understood, especially when considering the apparent overlap and redundancy of the two IL-1 molecules. Characterization of IL-1alpha and IL-1beta expression was performed in this study in organs from young and old mice, using immunohistochemistry and ELISA (enzyme-linked immunosorbent assay). The results indicate that organ IL-1alpha and IL-1beta display different patterns of expression: IL-1alpha is manifested more prominently in lymphoreticular organs (lungs, small intestine, spleen, liver), while IL-1beta is more evident in highly specialized and more vulnerable organs, which do not play a leading role in defense against infections and intoxication (heart, brain, skeletal muscle, kidney). This differential expression is more accentuated in old mice, possibly pointing to the special relevance of these cytokines to organ homeostasis in old age. These findings may shed new light on the physiological functions of IL-1alpha and IL-1beta, and may also lead to the development of improved therapeutic approaches, based on the specific manipulation of these cytokines. 相似文献
32.
Benezra M Ishai-Michaeli R Ben-Sasson SA Vlodavsky I 《Journal of cellular physiology》2002,192(3):276-285
A series of nine synthetic polyaromatic compounds were synthesized by polymerization of aromatic ring monomers with formaldehyde, which yield substantially ordered backbones with different functional anionic groups (hydroxyl and carboxyl) on the phenol ring. These compounds were tested for their heparin-mimicking activity: (1) inhibition of heparanase activity; (2) inhibition of SMC proliferation; and (3) release of bFGF from the ECM. We demonstrate that compounds that have two hydroxyl groups para and ortho to the carboxylic group and a carboxylic group at a distance of two carbons from the phenol ring inhibit heparanase activity and SMC proliferation, as well as induced an almost complete release of bFGF from ECM. Addition of a methyl group next to the carboxylic group led to a preferential inhibition of heparanase activity. Similar results were obtained with a compound that contains one hydroxyl group para to the carboxylic group and an ether group near the carboxylic group on the phenol ring. Preferential inhibition of SMC proliferation was best achieved when the position of the hydroxyl group is para and ortho to the carboxylic group and the carboxylic group is at a distance of one carbon from the phenol ring. On the other hand, for maximal release of bFGF from ECM, the position of the carboxylic group should be three carbons away from the phenol ring. These new heparin-mimicking compounds may have a potential use in inhibition of tumor metastasis, arteriosclerosis, and inflammation. 相似文献
33.
Soybean vegetative storage proteins (S-VSPs) accumulate to high levels in vacuoles of both wild types and heterologous plants. Here it is shown that directing S-VSPalpha to two different organelles-chloroplasts and vacuoles-in a single transgenic plant significantly increased its accumulation. Accumulation of S-VSPalpha in heterologous plants correlated with total soluble lysine. Using this approach with essential amino-acid-rich transgene proteins may lead to a breakthrough in improving plant nutritional quality. 相似文献
34.
Ben-Abraham R Gazit V Vofsi O Ben-Shlomo I Reznick AZ Katz Y 《Journal of cellular biochemistry》2003,90(5):957-963
Previous investigation demonstrated the potential of beta-phenylpyruvate at high concentration to cause hypoglycemia in mice totally deprived of insulin. For further elucidation of the glucose-lowering mechanism, glucose uptake, and quantity of glucose transporters (GLUT1 and GLUT4) in mouse soleus muscle and C2C12 muscle cell lines were investigated following incubation with beta-phenylpyruvate in various concentrations. A marked enhancement of glucose uptake was demonstrated that peaked at 0.5 and 1.0 mM beta-phenylpyruvate in soleus muscle (P<0.01) and C2C12 cells (P<0.001), respectively. Kinetic analysis in C2C12 cells showed a twofold increase in Vmax compared with controls (P<0.001). In addition, both GLUT1 and GLUT4 levels were increased following exposure to beta-phenylpyruvate. Our findings point to a peripheral hypoglycemic effect of beta-phenylpyruvate. 相似文献
35.
36.
Volberg T Bershadsky AD Elbaum M Gazit A Levitzki A Geiger B 《Cell motility and the cytoskeleton》2000,45(3):223-234
Tyrphostin AG-1714 and several related molecules with the general structure of nitro-benzene malononitrile (BMN) disrupt microtubules in a large variety of cultured cells. This process can be inhibited by the stabilization of microtubules with taxol or by pretreatment of the cells with pervanadate, which inhibits tyrosine phosphatases and increases the overall levels of phosphotyrosine in cells. Unlike other microtubule-disrupting drugs such as nocodazole or colchicine, tyrphostin AG-1714 does not interfere with microtubule polymerization or stability in vitro, suggesting that the effect of this tyrphostin on microtubules is indirect. These results imply an involvement of protein tyrosine phosphorylation in the regulation of overall microtubule dynamics. Tyrphostins of AG-1714 type could thus be powerful tools for the identification of such microtubule regulatory pathways. 相似文献
37.
Glycoprotein IIb/IIIa antagonists have been shown to be effective in reducing thrombotic complications prior to high-risk coronary interventions. Some studies have reported improved coronary flow after abciximab in slow or no-reflow phenomenon. We report a case in which abciximab did not clear the thrombotic occlusion or restore artery flow. Further studies are needed into the refractory no-flow phenomenon. 相似文献
38.
Galili S Guenoune D Wininger S Hana B Schupper A Ben-Dor B Kapulnik Y 《Transgenic research》2000,9(2):137-144
Threonine, lysine, methionine, and tryptophan are essential amino acids for humans and monogastric animals. Many of the commonly used diet formulations, particularly for pigs and poultry, contain limiting amounts of these amino acids. One approach for raising the level of essential amino acids is based on altering the regulation of their biosynthetic pathways in transgenic plants. Here we describe the first production of a transgenic forage plant, alfalfa (Medicago sativa L.) with modified regulation of the aspartate-family amino acid biosynthetic pathway. This was achieved by over-expressing the Escherichia coli feedback-insensitive aspartate kinase (AK) in transgenic plants. These plants showed enhanced levels of both free and protein-bound threonine. In many transgenic plants the rise in free threonine was accompanied by a significant reduction both in aspartate and in glutamate. Our data suggest that in alfalfa, AK might not be the only limiting factor for threonine biosynthesis, and that the free threonine pool in this plant limits its incorporation into plant proteins. 相似文献
39.
Shai Rahimipour Lev Weiner Prativa Bade Shrestha-Dawadi Shmuel Bittner Yitzhak Koch Mati Fridkin 《Letters in Peptide Science》1998,5(5-6):421-427
In an attempt to produce efficient cytotoxic derivatives of luteinizing hormone-releasing hormone (LH-RH), two novel 1,4-naphthoquinone derivatives of [D-Lys6]-LH-RH were synthesized primarily by solid-phase peptide synthesis, in good yield and high purity. The ability of each analog to produce reactive oxygen species using enzymatic reduction, i.e. NADPH-cytochrome P-450 reductase, was evaluated employing electron spin resonance (ESR) spectroscopy and spin-trapping techniques. The ESR results suggest that the novel cytotoxic analogs are extremely effective in generating oxygen radicals. 相似文献
40.
Shela Gorinstein Marina Zemser Moshe Weisz Shmuel Halevy Olga Martin-Belloso Simon Trakhtenberg 《The Journal of nutritional biochemistry》1998,9(12):682-686
It is an established fact that moderate consumption of alcoholic beverages leads to some positive biochemical changes in blood that are widely regarded as indicators of improved prevention of atherosclerosis. However, at present, there are different opinions regarding the biologically active compounds of alcoholic beverages that bring about these changes. This experiment was conducted on 60 male Wistar rats, which were divided into five groups, each of which contained 12 rats: four experimental groups (EG1, EG2, EG3, EG4) and one control group (CG). During 4 weeks, all groups of rats were fed basal diet (BD) supplemented with dry red wine (EG1), beer (EG2), lyophilized dry red wine (EG3), or lyophilized beer (EG4). The rats of the CG were fed BD only. The rats of EG1 and EG2 were fed BD supplemented daily with 2.0 mL of wine and 6.0 mL of beer, respectively. The rats of EG3 and EG4 were fed BD supplemented daily with lyophilized wine and lyophilized beer at a concentration corresponding to an intake of 2.0 mL of original wine and 6.0 mL of original beer, respectively. Before and after completion of the trial, a wide range of laboratory tests including lipids and lipid peroxides were performed. The results of this investigation reveal that both original and lyophilized wine and beer exercise statistically significant beneficial lipidemic and antioxidant effects by reducing total cholesterol (TC), low density lipoprotein cholesterol, triglycerides, and lipid peroxides (P < 0.05 for all) and by elevating the high density lipoprotein cholesterol:TC ratio. There were no statistically significant differences in the results between groups fed BD supplemented with original wine and beer versus groups fed BD supplemented with lyophilized wine and beer. Therefore, it can be concluded that the biologically active compound of these beverages is their dry matter containing inter alia polyphenols in relatively high concentrations. 相似文献