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121.
Choi YS Cho ES Je YH Roh JY Chang JH Li MS Seo SJ Sohn HD Jin BR 《Current microbiology》2004,48(1):47-50
Bacillus thuringiensis 656-3, isolated from a soil sample collected at mushroom houses, showed high toxicity to mushroom flies, Lycoriella mali and Coboldia fuscipes. B. thuringiensis 656-3 produced bipyramidal inclusions and reacted with the H antiserum of B. thuringiensis subsp. morrisoni (H8a8b). The plasmid and protein profiles of B. thuringiensis 656-3 were similar to those of its reference strain, subsp. morrisoni PG-14. However, PCR analysis using cry gene primers showed that B. thuringiensis 656-3, unlike its reference strain, had cry4A, cry4B, cry10A, cry11A, and cry1Ac genes, suggesting that B. thuringiensis 656-3 was a unique strain with respect to gene type. In addition, B. thuringiensis 656-3 showed a high level of toxicity against mushroom flies, L. mali and C. fuscipes. 相似文献
122.
The present study investigated the effect of 1-methylated beta-carbolines (harmaline, harmalol and harmine) on change in the mitochondrial membrane permeability and cell death due to reactive nitrogen species in differentiated PC12 cells. beta-Carbolines, caspase inhibitors (z-LEHD.fmk and z-DQMD.fmk) and antioxidants (N-acetylcysteine, dithiothreitol, melatonin, carboxy-PTIO and uric acid) depressed cell viability loss due to 3-morpholinosydnonimine (SIN-1) in PC12 cells. beta-Carbolines inhibited the nuclear damage, the decrease in mitochondrial transmembrane potential, the cytochrome c release, the formation of reactive oxygen species and the depletion of GSH caused by SIN-1 in PC12 cells. beta-Carbolines decreased the SIN-1-induced formations of 3-nitrotyrosine, malondialdehyde and carbonyls in PC12 cells. The results show that 1-methylated beta-carbolines attenuate SIN-1-induced mitochondrial damage. This results in the inhibition of caspase-9 and -3 and apoptotic cell death in PC12 cells by suppressing the toxic actions of reactive oxygen and nitrogen species, including the GSH depletion. 相似文献
123.
It has been suggested that infectious entry of rubella virus (RV) is conducted by receptor mediated endocytosis. To explore the cellular entry mechanism of RV, inhibitory effects of drugs affecting various endocytic pathways on RV entry into VeroE6 cells were analyzed. Results showed that RV infectious entry into VeroE6 cells is mediated by clathrin-dependent endocytosis and not by caveolae-mediated endocytosis. Moreover, chemical inhibition of macropinocytosis such as treatments of amiloride, actin and microtubule-disrupting drug significantly reduced RV infection. Considering that macropinocytosis is inducible endocytosis by cellular stimulations, clathrin-mediated endocytosis is likely to be a major route of RV infectious entry. 相似文献
124.
Jeong YK Yang WS Kim KH Chung KT Joo WH Kim JH Kim DE Park JU 《Biotechnology letters》2004,26(5):393-397
A fibrinolytic enzyme, myulchikinase, from a Korean seasoning ingredient, myul-chi-jeot-gal, has been purified to electrophoretic homogeneity. The molecular mass of the myulchikinase was estimated to about 28 kDa by SDS-PAGE and gel filtration. Amino acid sequence of the NH2-terminal of myulchikinase showed significant homology with other fibrinolytic enzymes including trypsin from starfish, katsuwokinase, and rat pancreatic elastase II. The purified myulchikinase hydrolyzed various synthetic substrates with different substrate specificity and cytotoxic to the tumor cell lines. 相似文献
125.
Dombroski MA Letavic MA McClure KF Barberia JT Carty TJ Cortina SR Csiki C Dipesa AJ Elliott NC Gabel CA Jordan CK Labasi JM Martin WH Peese KM Stock IA Svensson L Sweeney FJ Yu CH 《Bioorganic & medicinal chemistry letters》2004,14(4):919-923
The synthesis and in vitro p38 alpha activity of a novel series of benzimidazolone inhibitors is described. The p38 alpha SAR is consistent with a mode of binding wherein the benzimidazolone carbonyl serves as the H-bond acceptor to Met109 of p38 alpha in a manner analogous to the pyridine nitrogen of prototypical pyridylimidazole p38 inhibitors. Potent p38 alpha activity comparable to that of several previously reported p38 inhibitors is observed for this novel chemotype. 相似文献
126.
127.
Sun-A?Kim Seong-Ki?Kim Peter?B.?Kaufman June?Seung?LeeEmail author Soo?Chul?ChangEmail author 《Journal of Plant Biology》2004,47(4):307-313
We investigated chilling-induced changes in ethylene levels in Arabidopsis to find plants with distinct patterns of ethylene
production in the cold-related biosynthetic pathway. The sensitive mutants identified here includedchs1-2,chs4-2, andchs6-2. Among these, plants of thechs4-2 mutant produced more ethylene than did the wild type after both were transferred from 4°C or 10°C to 22°C. This mutant also
showed less freezing tolerance and more electrolyte leakage than the wild-type plants. Our results suggest a relationship
between ethylene biosynthesis and chilling sensitivity in the mutant To determine which of the enzymes involved in ethylene
biosynthesis were induced by chilling, we tested the activities of ACC synthase and ACC oxidase in both mutant and wild-type
plants, and found greater activity by ACC synthase as well as a higher ACC content in the mutants after all the plants were
transferred from 10°C to 22°C. However, ACC oxidase activity did not differ between mutant and wild-type plants in response
to chilling treatment Therefore, we conclude thatchs4-2 mutants produce more ethylene than do other mutants or the wild type during their recovery from chilling conditions. Furthermore,
we believe that ACC synthase is the key enzyme involved in this response. 相似文献
128.
Sei?Kwang?HahnEmail author Allan?S.?Hoffman 《Biotechnology and Bioprocess Engineering》2004,9(3):179-183
A biocompatible polyelectrolyte complex multilayer (PECML) film consisting of poly-L-lysine (PLL) as a polycation and hyaluronic
acid (HA) as a polyanion was developed to test its use for surface modification to prevent cell attachment and protein drug
delivery. The formation of PECML through the electrostatic interaction of HA and PLL was confirmed by contact angle measurement,
ESCA analysis, and HA content analysis. HA content increased rapidly up to 8 cycles for HA/PLL deposition and then slightly
increased with an increasing number of deposition cycle.In vitro release of PLL in the PECML continued up to 4 days andca. 25% of HA remained on the chitosan-coated cover glass afterin vitro release test for 7 days. From the results, PECML of HA and PLL appeared to be stable for about 4 days. The surface modification
of the chitosan-coated cover glass with PECML resulted in drastically reduced peripheral blood mononuclear cell (PBMC) attachment.
Concerned with its use for protein drug delivery, we confirmed that bovine serum albumin (BSA) as a model protein could be
incorporated into the PECML and its release might be triggered by the degradation of HA with hyaluronidase. 相似文献
129.
Charlene?B.?Hubbard David?J.?GarbaryEmail author Kwang?Young?Kim David?M.?Chiasson 《Helgoland Marine Research》2004,58(1):18-25
Kelp gametophytes were previously observed in nature living endophytically in red algal cell walls. Here we examine the interactions of two kelp species and six red algae in culture. Gametophytes of Nereocystis luetkeana (Mertens) Postels et Ruprecht became endophytic in the cell walls of Griffithsia pacifica Kylin and Antithamnion defectum Kylin, and grew epiphytically in high abundance on G. japonica Okamura and Aglaothamnion oosumiense Itono. Alaria esculenta (Linnaeus) Greville from the Atlantic coast of Nova Scotia became endophytic in Aglaothamnion oosumiense, Antithamnion defectum, Callithamnion sp., G. japonica, G. pacifica, and Pleonosporium abysicola Gardner, all from the Pacific Ocean. Some cultures were treated with phloroglucinol before infection to thicken the cell walls. The endophytic gametophytes were smaller and grew more slowly than gametophytes epiphytic on the same host. N. luetkeana failed to become endophytic in some of the potential hosts, and this may reflect host specificity, or culture artifacts. This work improves our understanding of the process of infection of red algae by kelp gametophytes, and broadens our knowledge of host specificity in endophytic symbioses.Communicated by K. Lüning 相似文献
130.
RIPK 2 is adapter molecule in the signal pathway involved in Toll-like receptors. However, there has been no reported association between receptor-interacting serine/threonine kinase 2 (RIPK 2) expression and the infectious diseases involving mycobacterial infection. This study found that its expression was down-regulated in the footpads and skin but was up-regulated in the liver of Mycobacterium leprae-infected nu/nu mice compared with those of the M. leprae non-infected nu/nu mice. It was observed that the interlukin-12p40 and interferon-gamma genes involved in the susceptibility of M. leprae were down-regulated in the skin but were up-regulated in the liver. Overall, this suggests that regulation of RIPK 2 expression is tissue-specifically associated with M. leprae infection. 相似文献