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101.
Kim DU Roh TY Lee J Noh JY Jang YJ Hoe KL Yoo HS Choi MU 《Biochimica et biophysica acta》1999,1437(3):409-414
We cloned and expressed a full-length cDNA encoding a phospholipase D of type alpha (PLDalpha) from cabbage. Analysis of the cDNA predicted an 812-amino-acid protein of 92.0 kDa. The deduced amino acid sequence of cabbage PLD has 83% and 80% identity with Arabidopsis PLDalpha and castor bean PLD, respectively. Expression of this cDNA clone in E. coli shows a functional PLD activity similar to that of the natural PLD. 相似文献
102.
Rectangular flap for horizontal upper vermilion tightness in secondary cleft lip deformity 总被引:1,自引:0,他引:1
Radical paring of the cleft edge during a primary cleft operation or repeated secondary surgeries can result in tightness of the upper lip. The degree of the resulting side-to-side tension can vary, from mild cases for which improvement is sought through realignment of the misplaced oral sphincter muscle in secondary revision, to severe cases for which the possibility of a lip switch flap must be considered. When the lip tightness accompanies more than three-quarters loss of the Cupid's bow, an Abbé flap is an alternative. However, the lip switch flap is far from ideal, in both artistic and functional perspectives, and should be avoided if at all possible in mild to moderate degrees of lip tightness. This study presents a method of correcting horizontal cleft upper lip tightness, especially of the vermilion. The method involves local transfer of an inferiorly based rectangular flap from the relatively redundant upper two-thirds to the lower one-third of the upper lip and vermilion. Primary indications for the technique include vermilion tightness with half to three-quarters loss of Cupid's bow. The method has the advantage of supplementing the horizontal lip dimension on the cleft side and restoring a natural Cupid's bow, thereby repositioning the shifted philtral column and adding fullness to the lower one-third of the upper lip. Incorporation of the upper lip scar in the rectangular flap removes ugly scars and spares the lower lip from surgical violation. The orbicularis sphincter function, as seen in facial animation, was well regained. Twenty unilateral and three bilateral cases with a maximal follow-up period of 4.5 years are presented. 相似文献
103.
The mortality and morbidity associated with neonatal gram-negative meningitis have remained significant despite advances in antimicrobial chemotherapy. Escherichia coli K1 is the most common gram-negative organism causing neonatal meningitis. Our incomplete knowledge of the pathogenesis of this disease is one of the main reasons for this high mortality and morbidity. We have previously established both in vitro and in vivo models of the blood-brain barrier (BBB) using human brain microvascular endothelial cells (HBMEC) and hematogenous meningitis in neonatal rats, respectively. With these in vitro and in vivo models, we have shown that successful crossing of the BBB by circulating E. coli requires a high-degree of bacteremia, E. coli binding to and invasion of HBMEC, and E. coli traversal of the BBB as live bacteria. Our previous studies using TnphoA, signature-tagged mutagenesis and differential fluorescence induction identified several E. coli K1 determinants such as OmpA, Ibe proteins, AslA, TraJ and CNF1 contributing to invasion of HBMEC in vitro and traversal of the blood-brain barrier in vivo. We have shown that some of these determinants interact with specific receptors on HBMEC, suggesting E. coli translocation of the BBB is the result of specific pathogen-host cell interactions. Recent studies using functional genomics techniques have identified additional E. coli K1 factors that contribute to the high degree of bacteremia and HBMEC binding/invasion/transcytosis. In this review, we summarize the current knowledge on the mechanisms underlying the successful E. coli translocation of the BBB. 相似文献
104.
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
105.
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
106.
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
107.
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
108.
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
109.
110.
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