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J Schalkwijk IM van Vlijmen JA Alkemade GJ de Jongh 《Canadian Metallurgical Quarterly》1993,100(4):390-393
Recently we have reported the purification and biochemical characterization of a new, inducible elastase inhibitor [skin-derived antileukoproteinase (SKALP)], which could be extracted in high amounts from psoriatic skin but not from normal human skin. Here we demonstrate the immunohistochemical localization of SKALP in psoriatic epidermis. SKALP was found exclusively in the upper layers of the suprabasal compartment and stratum corneum of lesional psoriatic epidermis. Basal keratinocytes were always negative. No immunoreactive SKALP was found in normal epidermis and non-lesional psoriatic epidermis, in accordance with findings in functional assays. Western blots of skin extracts from psoriatic and normal skin confirmed the immunohistochemical findings and revealed two major bands with apparent molecular weights of 10.5 and 11.5 kDa. We would hypothesize that SKALP could act as a modulator of epidermal inflammation by interfering with polymorphonuclear leukocyte trafficking, and that it could protect structural proteins against elastase-mediated damage. 相似文献
135.
Gamma-glutamyltranspeptidase (GGT, EC 2.3.2.2) activity was determined in the plasma and liver of 40 young (50 days old) and 40 mature (300 days old) male Wistar rats, after a protein restriction period of 28 days. Casein protein levels used were: 1%, 3%, 5%, 7% and 28% (control). Weanling rats submitted to protein-free diet and adult rats submitted to that and other low-protein diets (1%, 3% or 5% casein) presented weight reductions (-0.38 +/- 0.07 g/day and -0.98 +/- 0.19 g/day, respectively). Only in young animals did these weight reductions parallel those of food consumption (37 +/- 12% of control), plasma protein (52 +/- 11% of control), plasma albumin (70 +/- 12% of control), hepatic RNA (68 +/- 7% of control) and protein (71 +/- 8% of control). A marked effect of the protein restriction, increasing the GGT activity, was also observed only in young rats. A significant (P < 0.05) rise was promoted by the protein-free diet in the plasma GGT (2.83 +/- 1.39 vs 0.69 +/- 0.50 mU/ml for control) and by both the protein-free and 3% casein diets, in the liver GGT (respectively, 16.00 +/- 6.72 and 7.75 +/- 3.49 vs 0.94 +/- 0.57 U/g protein for control). The different results obtained for young in relation to mature animals could be explained by the reduction of both protein and sulfur-containing amino acid requirements with aging. 相似文献
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BA Rakel MA Bermel LI Abbott SK Baumler MR Burger CJ Dawson JA Heinle IM Ocheltree 《Canadian Metallurgical Quarterly》1998,11(4):174-182
Split-thickness skin grafting (STSG) is a frequently used reconstructive technique but is associated with a large variation in practice. The purposes of this article are to integrate and synthesize the available empirical evidence regarding STSG donor site dressings, identify which dressings are associated with the best outcomes, and provide practice recommendations. This review of 33 studies found transparent film to be the best dressing for the care of STSG donor site wounds. Transparent film was associated with one of the fastest healing rates (9.47 days), a smooth epithelialized surface, a low infection rate (10 out of 394 patients or 3%), the least amount of pain (1.59 on 0 to 10 scale), and minimal cost ($.005 per square inch) when compared with other dressings. 相似文献
138.
The interaction of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 with CD4 CDR3-related peptide derivatives showing anti-HIV-1 activity has been studied. Conformational changes in gp120, which could affect its interaction with CD4 and its shedding from virions, were detected by fluorescence spectrum analysis of tryptophan residues after addition of peptide representative of the CD4 CDR3-related region, but not the CD4 CDR2-related region. Interestingly, the addition of scrambled peptide, S1 (with altered amino acid sequence compared with the native CDR3-related peptide but unaltered overall composition), which we recently showed to have stronger anti-HIV-1 activity than the original CDR3-related peptide, had no effects on the conformational change in gp120 or on its interaction with CD4 and its shedding from HIV-1 virions. However, all of the CDR3-related peptides, including S1, showed blocking effects on the binding of antibodies against gp120 V3 loop and C-terminus regions. Thus, we concluded that there were at least two separable activities of the CDR3-related peptides in anti-HIV-1 activity, i.e. induction of conformational changes in gp120, which could affect its binding to CD4 and to gp41 (as observed in native CDR3-related peptides), and inactivation of V3 loop and C-terminus regions in gp120 (as observed in all of the CDR3-related peptides, including S1). 相似文献
139.
PA Robinson JP Leek IM Carr A Bailey NJ Lench J Morrison WJ Hume AS High AF Markham 《Canadian Metallurgical Quarterly》1996,41(5):445-452
Heparin has been shown to decrease total vascular resistance while protamine stimulates endothelium-dependent vasodilation. This study was undertaken to determine whether heparin and/or protamine could enhance endothelium-derived relaxing factor (EDRF), as determined by nitric oxide (NO) production. Porcine carotid artery endothelial cells (PAECs) were seeded on multiwell plates, grown to confluence, and exposed to heparin (1-20 U/ml) or protamine (50-200 microg/ml) for 24 hours. With the addition of the NO synthase inhibitor, N(G)-monomethyl-L-arginine (NMMA), to heparin and/or protamine, the medium samples were collected in one hour. In a parallel clinical study, plasma samples were collected from patients undergoing cardiopulmonary bypass (CPB). The NO production was measured as reflected by the formation of nitrite (NO2-) and nitrate (NO3-), the stable end-metabolites of NO. NO production by PAECs was significantly increased by heparin > or = 5 U/ml or protamine > or = 50 microg/ml in a concentration-dependent manner. The increase of NO production was prevented by the addition of NMMA. In CPB patients, plasma NO2-/NO3- concentration was significantly increased after heparin administration compared to the preoperative value, at which time the mean plasma heparin level was 4.9+/-0.5 U/ml. Following slow protamine infusion, there was no significant difference in plasma NO2-/NO3- concentration compared to preoperative value. In conclusion NO production increases following exposure of PAECs to heparin and/or protamine. In patients, NO concentration significantly increased after heparin administration by IV bolus, but not with a slow infusion of protamine after CPB. 相似文献
140.
EK Khusnutdinova IM Khidiiatova MI Prosniak KhS Rafikov SA Limborskaia 《Canadian Metallurgical Quarterly》1994,30(12):1621-1625
Hyperpolymorphism of minisatellite DNA, detected using the M13 bacteriophage DNA hybridization probe, was studied in three ethnographic groups of Bashkirs and in the Komi population. Bands from 2 to 20 kb were analyzed in hybridization patterns. A significant population difference was detected both in evaluation of the average number of hybridization fragments per individuals and in the distribution of frequency of some fractions. Thus, it seems possible to describe a set of so-called characteristic fractions for each population. According to the hybridization fragment frequency for the populations investigated, an index of genetic similarity was calculated. The possibility of using this kind of multiple polymorphism of DNA in population genetic investigations at the level of ethnic groups and peoples is discussed, and a conclusion is made about the necessity of searching for the most informative methods of analyzing the data obtained. 相似文献