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71.
The Cry2Aa3 gene was introduced into asporogenic Bacillus thuringiensis, and the synthesized protoxin killed Bombyx mori and Lymantria dispar larvae. Chymotrypsin hydrolyzed the linkages between 49Tyr/Val50 and 145Lys/Ser146 in the protoxin, and 50- and 58-kDa fragments were generated, respectively. Both peptides killed the larvae of both insects.  相似文献   
72.
A series of cis-1,2-diaminocyclohexane derivatives possessing a 6–6 fused ring for the S1 moiety were synthesized as novel factor Xa (fXa) inhibitors. The synthesis, structure–activity relationship (SAR), and physicochemical properties are reported herein, together with the discovery of compound 45c, which has potent anti-fXa activity, good physicochemical properties and pharmacokinetic (PK) profiles, including a reduced negative food effect.  相似文献   
73.
The antigen stimulation of RBL-2H3 cells induced interleukin 13 (IL-13) production, which was inhibited by the steroidal anti-inflammatory drug dexamethasone and by the c-Jun N-terminal kinase (JNK) inhibitor SP600125. Dexamethasone did not inhibit the antigen-induced phosphorylation of JNK but inhibited that of c-Jun. In a cell-free system, the phosphorylation of glutathione S-transferase-fused c-Jun by recombinant JNK was not inhibited by dexamethasone but was inhibited by the addition of recombinant glucocorticoid receptor (GR). These findings suggest that the inhibition of antigen-induced IL-13 production by dexamethasone is due to the GR-mediated inhibition of c-Jun phosphorylation induced by JNK.  相似文献   
74.
Two new phenylethanoid glycosides integrifoliosides A (2) and B (3), along with a known phenylethanoid glycoside alyssonoside (1) and a flavone glucoside chrysoeriol-7-O-beta-D-glucopyranoside (4) were isolated from the aerial parts of Phlomis integrifolia. The structures of the new compounds were identified as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1 --> 4)-alpha-L-rhamnopyranosyl-(1 --> 3)-4-O-feruloyl-beta-D-glucopyranoside (2) and 3-hydroxy-4-methoxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1 --> 4)-alpha-L-rhamnopyranosyl-(1 --> 3)-4-O-feruloyl-beta-D-glucopyranoside (3), on the basis of spectroscopic (UV, IR, 1D- and 2D-NMR, and HR-FABMS) methods.  相似文献   
75.
In order to investigate the effect of the fixation of the orientations of the two long chains, three types of novel derivatives of scavenger receptor inhibitor 1 were synthesized, and their biological activities were evaluated. Among the novel derivatives, 2,4-bis(octadecanoylamino)benzenesulfonic acid sodium salt (4d) showed the most potent inhibitory activity against the incorporation of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-labeled acetyl-LDL (DiI-acetyl-LDL) into macrophages. 2,5-Bis(octadecanoylamino)benzenesulfonic acid sodium salt (4c), a regioisomer of 4d, did not exhibit as potent an inhibitory activity as 4d, meaning that the substitution pattern of two long chains on the benzene ring must be important. Compound 4d exhibited 10 times more potent inhibitory activity against the binding of 125I-labeled acetyl-LDL to the surface of macrophages than compound 1.  相似文献   
76.
77.
Ohtsuka I  Hada N  Sugita M  Takeda T 《Carbohydrate research》2002,337(21-23):2037-2047
Glycosphingolipids isolated from larvae of the green-bottle fly, Lucilia caesar, have quite unique structures containing GlcNAcbeta-(1 --> 3)-Man and GalNAcbeta-(1 --> 4)-GlcNAcbeta-(1 --> 3)-Man. We have synthesized two glycosphingolipids, beta-D-GlcNAcp-(1 --> 3)-beta-D-Manp-(1 --> 4)-beta-D-Glcp-(1 --> 1)-Cer and beta-D-GalNAcp-(1 --> 4)-beta-D-GlcNAcp-(1 --> 3)-beta-D-Manp-(1 --> 4)-beta-D-Glcp-(1 --> 1)-Cer. A key reaction in the synthetic sequence is the application of the intramolecular aglycon delivery (IAD) approach for the synthesis of the beta-mannopyranosidic linkages.  相似文献   
78.
In the mouse macrophage-like cell line RAW 264, vacuolar-type (H(+))-ATPase (V-ATPase) inhibitors, bafilomycin A(1) and concanamycin A, increased the level of cyclooxygenase (COX)-2 protein and its mRNA. The V-ATPase inhibitor-induced expression of COX-2 was suppressed by inhibitors of c-jun N-terminal kinase (JNK) and nuclear factor-kappaB, and by inhibitors of Na(+)/H(+) exchangers (NHEs). The bafilomycin A(1)-induced activation of JNK but not degradation of IkappaB-alpha was suppressed by NHE inhibitors and by an inhibitor of Na(+)/Ca(2+) exchanger SN-6. These results suggested that V-ATPase inhibitors induce the expression of COX-2 via NHE-dependent and -independent pathways.  相似文献   
79.
A novel glycosphingolipid, beta-D-GalNAcp(1-->4)[alpha-D- Fucp(1-->3)]-beta-D-GlcNAcp(1-->)Cer (1), isolated from the marine sponge Aplysinella rhax, has a unique structure, with D-fucose and N-acetyl-D-galactosamine attached to a reducing-end N-acetyl-D-glucosamine through an alpha1-->3 and beta1-->4 linkage, respectively. We synthesized glycolipid analogues carrying a 2-branched fatty alkyl residue or a 2-trimethylsilyl ethyl residue in place of ceramide (2 and 3), non-natural type trisaccharide analogue containing an L-fucose residue (4), and other analogues (5 and 6). Among these prepared compounds, 2 showed the most potent nitric oxide (NO) production inhibitory activity against LPS-activated J774.1 cells. In addition, their structure-activity relationships were established.  相似文献   
80.
Sato  Takashi  Onoma  Noriyasu  Fujikake  Hiroyuki  Ohtake  Norikuni  Sueyoshi  Kuni  Ohyama  Takuji 《Plant and Soil》2001,237(1):129-135
Soybean nodules contain four major leghemoglobin (Lb) components, Lba, Lbc1, Lbc2 and Lbc3. A sensitive and selective method for quantitative analysis of the four Lb components was devised with capillary isoelectric focusing (CIEF). The changes in the concentrations of four Lb components in nodules during the initial stages of development were compared between hypernodulating soybean mutant NOD1–3 and its parent cv. Williams. The hydroponically cultivated soybean plants were periodically sampled. All the visible nodules were collected from the roots, and then the four Lb components in the largest nodules were analyzed with the CIEF method. In NOD1–3 Lbs were initially detected at 19 days after sowing (DAS), a few days earlier than in Williams at 22 DAS. The Lbcs (Lbc1, Lbc2 and Lbc3) were the main component at the earliest nodule growth stage, and the relative proportion of Lba increased with nodule growth in both NOD1–3 and Williams. This result is in agreement with previous observation, and the CIEF method is considered to be useful for Lb components analysis to define their function and gene expression.  相似文献   
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