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81.
Fourteen mono- and dichloro-8-quinolinols were tested against five fungi (Aspergillus niger, A. oryzae, Myrothecium verrucaria, Trichoderma viride, and Mucor circinelloides) and compared with the fungitoxicity of 8-quinolinol in Yeast Nitrogen Base containing 1% D-glucose and 0.088% L-asparagine. All of the compounds were more fungitoxic than 8-quinolinol except for the surprising activity of 8-quinolinol against A. oryzae. Mixtures of the MICs of monochloro- and dichloro-8-quinolinols in which the halogens were in different positions of the quinoline ring showed synergism. Comparable mixtures in which one position of each compound was occupied by the same halogen showed additive activity. In a different study we showed that 3,5,6-, 3,5,7-, 4,5,7-, and 5,6,7-trichloro-8-quinolinols were not toxic to M. circinelloides, whereas the combinations of the correspondingly substituted mono- and dichloro-8-quinolinols as well as 3,6-dichloro- and 5,7-dichloro-8-quinolinols were inhibitory. This indicated that a steric factor can be involved in affecting fungitoxicity. 相似文献
82.
Frénal K Xu CQ Wolff N Wecker K Gurrola GB Zhu SY Chi CW Possani LD Tytgat J Delepierre M 《Proteins》2004,56(2):367-375
The gamma-KTx-type scorpion toxins specific for K+ channels were found to interact with ERG channels on the turret region, while alpha-KTx3.2 Agitoxin-2 binds to the pore region of the Shaker K+ channel, and alpha-KTx5.3 BmP05 binds to the intermediate region of the small-conductance calcium-activated K-channel (SK(Ca)). In order to explore the critical residues for gamma-KTx binding, we determined the NMR structure of native gamma-KTx1.1 (CnErg1), a 42 amino acid residues scorpion toxin isolated from the venom of the Mexican scorpion Centruro?des noxius Hoffmann, and we used computational evolutionary trace (ET) analysis to predict possible structural and functional features of interacting surfaces. The 1H-NMR three-dimensional solution structure of native ergtoxin (CnErg1) was solved using a total of 452 distance constraints, 13 3J(NH-Halpha) and 10 hydrogen bonds. The structure is characterized by 2 segments of alpha-helices and a triple-stranded antiparallel beta-sheet stabilized by 4 disulfide bridges. The ET and structural analysis provided indication of the presence of two important amino acid residue clusters, one hydrophobic and the other hydrophilic, that should be involved in the surface contact between the toxin and the channel. Some features of the proposed interacting surface are discussed. 相似文献
83.
Comparison of long-term survival of pigmented epidermal reconstructs cultured in vitro vs. xenografted on nude mice 总被引:2,自引:0,他引:2
Casoli V Cario-André M Costet P Pain C Taïeb A 《Pigment cell research / sponsored by the European Society for Pigment Cell Research and the International Pigment Cell Society》2004,17(1):87-92
Epidermal reconstructs incorporating pigment cells have been used in vitro over the last decade to study the physiology of the epidermal melanin unit. However, the major limitation of this technology is the duration of the assays, which need to be completed within 2-3 weeks to obviate the problem of epidermal senescence and excessive terminal differentiation. This becomes a major problem for studying long-term biological phenomena in photoprotection and epidermal skin cancers. We report here a simplified surgical technique in immunotolerant mice allowing long-term studies. The creation of a vascularized mouse skin flap is the key point of the surgical procedure. Long-term pigmentation of the xenografts seemed macroscopically successful, but surprisingly microscopy at 11 and 16 weeks postgrafting showed mostly dermal pigment aggregates and rare Melan-A positive dermal and epidermal pigment cells. In the same reconstructs maintained in vitro, dermal pigment and dermal pigment cells were never noted. It could be speculated that in our model, the colonization of the xenografted dead human dermis by murine cells influences melanocyte survival. 相似文献
84.
Extracellular acidification elicits a chloride current that shares characteristics with ICl(swell) 总被引:1,自引:0,他引:1
Nobles M Higgins CF Sardini A 《American journal of physiology. Cell physiology》2004,287(5):C1426-C1435
A Cl current activated by extracellular acidification, ICl(pHac), has been characterized in various mammalian cell types. Many of the properties of ICl(pHac) are similar to those of the cell swelling-activated Cl current ICl(swell): ion selectivity (I > Br > Cl > F), pharmacology [ICl(pHac) is inhibited by 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), 1,9-dideoxyforskolin (DDFSK), diphenylamine-2-carboxylic acid (DPC), and niflumic acid], lack of dependence on intra- or extracellular Ca2+, and presence in all cell types tested. ICl(pHac) differs from ICl(swell) in three aspects: 1) its rate of activation and inactivation is very much more rapid, currents reaching a maximum in seconds rather than minutes; 2) it exhibits a slow voltage-dependent activation in contrast to the fast voltage-dependent activation and time- and voltage-dependent inactivation observed for ICl(swell); and 3) it shows a more pronounced outward rectification. Despite these differences, study of the transition between the two currents strongly suggests that ICl(swell) and ICl(pHac) are related and that extracellular acidification reflects a novel stimulus for activating ICl(swell) that, additionally, alters the biophysical properties of the channel. cell swelling-activated chloride current; patch clamp; pH 相似文献
85.
Arnusch CJ André S Valentini P Lensch M Russwurm R Siebert HC Fischer MJ Gabius HJ Pieters RJ 《Bioorganic & medicinal chemistry letters》2004,14(6):1437-1440
A library of pentapeptides containing the sequence -Y-X-Y- based on rational design was screened with six different lectins. Sequences were identified that modulate galectin binding to its natural carbohydrate ligand. SPR showed inhibition values 2-3 times stronger than galactose and NMR studies suggested real carbohydrate mimicry. 相似文献
86.
Juriloff DM Harris MJ Dewell SL 《Birth defects research. Part A, Clinical and molecular teratology》2004,70(8):509-518
BACKGROUND: Nonsyndromic cleft lip with or without cleft palate, CL(P), is a common human birth defect with a complex unknown genetic cause. The mouse model is the "A/-" strains. Our previous studies mapped two loci: clf1 on Chr11 and clf2 on Chr13--with a strong genetic maternal effect on the level of risk. Here we test the hypothesis that CL(P) is digenic and identify candidate genes for clf1 and clf2. METHODS: We observed E14 CL(P) frequencies in backcross (BC1) embryos from a new cross of A/WySn to AXB-4/Pgn and from test crosses of three new "congenic RI" lines. Using new polymorphic markers from genes and our mapping panels of segregants and RI strains, we identified the candidate genes for clf1 and clf2. We sequenced the coding region of Ptch in A/WySn cDNA. RESULTS: Seventy new BC1 CL(P) segregants (4%) were obtained, as predicted. All three new congenic RI lines homozygous for both clf1 and clf2 had A/WySn-level CL(P) frequencies (10-30%) in test crosses. The clf1 region contains 10 known genes (Arf2, Cdc27, Crhr1, Gosr2, Itgb3, Mapt, Myl4, Nsf, Wnt3, and Wnt9b). The clf2 region contains 17 known genes with human orthologs. Both regions contain additional potential genes. No causal mutation in Ptch coding sequence was found. CONCLUSIONS: In A-strain mice, nonsyndromic CL(P) is digenic, suggesting that nonsyndromic human CL(P) may also be digenic. The orthologous human genes are on 17q (clf1) and 9q, 8q and 5p (clf2), and good candidate genes are WNT3 or WNT9B (17q), and PTCH (9q) or MTRR (5p). 相似文献
87.
88.
Sriraman R Bardor M Sack M Vaquero C Faye L Fischer R Finnern R Lerouge P 《Plant biotechnology journal》2004,2(4):279-287
Plant-based expression systems are attractive for the large-scale production of pharmaceutical proteins. However, glycoproteins require particular attention as inherent differences in the N-glycosylation pathways of plants and mammals result in the production of glycoproteins bearing core-xylose and core-alpha(1,3)-fucose glyco-epitopes. For treatments requiring large quantities of repeatedly administered glycoproteins, the immunological properties of these non-mammalian glycans are a concern. Recombinant glycoproteins could be retained within the endoplasmic reticulum (ER) to prevent such glycan modifications occurring in the late Golgi compartment. Therefore, we analysed cPIPP, a mouse/human chimeric IgG1 antibody binding to the beta-subunit of human chorionic gonadotropin (hCG), fused to a C-terminal KDEL sequence, to investigate the efficiency of ER retrieval and the consequences in terms of N-glycosylation. The KDEL-tagged cPIPP antibody was expressed in transgenic tobacco plants or Agrobacterium-infiltrated tobacco and winter cherry leaves. N-Glycan analysis showed that the resulting plantibodies contained only high-mannose (Man)-type Man-6 to Man-9 oligosaccharides. In contrast, the cPIPP antibody lacking the KDEL sequence was found to carry complex N-glycans containing core-xylose and core-alpha(1,3)-fucose, thereby demonstrating the secretion competence of the antibody. Furthermore, fusion of KDEL to the diabody derivative of PIPP, which contains an N-glycosylation site within the heavy chain variable domain, also resulted in a molecule lacking complex glycans. The complete absence of xylose and fucose residues clearly shows that the KDEL-mediated ER retrieval of cPIPP or its diabody derivative is efficient in preventing the formation of non-mammalian complex oligosaccharides. 相似文献
89.
Silva MD Savinainen A Kapadia R Ruan J Siebert E Avitahl N Mosher R Anderson K Jaffee B Schopf L Chandra S 《Molecular imaging》2004,3(4):312-318
Micro-computed tomographic (micro-CT) imaging provides a unique opportunity to capture 3-D architectural information in bone samples. In this study of pathological joint changes in a rat model of adjuvant-induced arthritis (AA), quantitative analysis of bone volume and roughness were performed by micro-CT imaging and compared with histopathology methods and paw swelling measurement. Micro-CT imaging of excised rat hind paws (n = 10) stored in formalin consisted of approximately 600 30-mum slices acquired on a 512 x 512 image matrix with isotropic resolution. Following imaging, the joints were scored from H&E stained sections for cartilage/bone erosion, pannus development, inflammation, and synovial hyperplasia. From micro-CT images, quantitative analysis of absolute bone volumes and bone roughness was performed. Bone erosion in the rat AA model is substantial, leading to a significant decline in tarsal volume (27%). The result of the custom bone roughness measurement indicated a 55% increase in surface roughness. Histological and paw volume analyses also demonstrated severe arthritic disease as compared to controls. Statistical analyses indicate correlations among bone volume, roughness, histology, and paw volume. These data demonstrate that the destructive progression of disease in a rat AA model can be quantified using 3-D micro-CT image analysis, which allows assessment of arthritic disease status and efficacy of experimental therapeutic agents. 相似文献
90.
Denizot Y Truffinet V Bouvier S Gainant A Cubertafond P Mathonnet M 《Mediators of inflammation》2004,13(1):53-54
This clinical study reports that blood levels of the pro-inflammatory mediator platelet-activating factor (PAF) did not change in colorectal cancer patients. In contrast, plasma levels of two enzymatic activities, one implicated in PAF production (i.e. phospholipase A2) and one in PAF degradation (i.e. PAF acetylhydrolase activity) were significantly elevated. 相似文献