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11.
Lorenzo GD Mansueto P Melluso M Morici G Norrito F Cigna D Candore G Caruso C 《Mediators of inflammation》1995,4(4):270-272
The aim of the present study was to compare serum levels of soluble forms of interleukin-2 receptor, CD4 and CD8, released by lymphocytes during activation of the immune system, in patients with allergic bronchial asthma, with those in healthy subjects. Significantly higher levels of soluble IL-2R and soluble CD4 were found in patients with asthma compared with the control group. In contrast, lower levels of soluble CD8 values were found in patients with asthma compared to the control group. Significant correlations were found for both sIL-2R and sCD4 and these two molecules, with lung function measured as bronchial responsiveness to inhaled methacholine. These results strengthen previous suggestions that in allergic bronchial asthma, activation of T cells plays a significant role in the disease pathogenesis. 相似文献
12.
Peptides corresponding to the N-terminal, central and central plus C-terminal domains of high mobility group protein HMG-1 from calf thymus have been isolated after digestion in solution with protease V8 under structuring conditions (0.35 M NaCl, pH 7.1). The effect of the interaction of these peptides with DNA on the topological properties of the nucleic acid has been studied and compared with the change in superhelicity produced by the whole protein. It appears that the region responsible for this effect is the central domain of HMG-1. The isolated N-terminal and central domains of this protein maintain their secondary and tertiary structure as observed by spectroscopic techniques. However, when the central domain is covalently linked only to the acidic C-terminal part of the molecule, its secondary and tertiary structures are lost as well as its property to alter DNA superhelicity. The results are discussed in relation to the interactions occurring between the different domains and the possible functional interactions of this protein. 相似文献
13.
R. Evangelisti M. Bodo A. Caruso E. Becchetti Prof. P. Carinci 《Cell and tissue research》1984,238(2):241-245
Summary Administration of Concanavalin A (Con A) to cultured skin fibroblasts derived from chick embryos at two developmental stages produce variations in the relative concentration of individual glycosaminoglycan (GAG) secreted by the cells. This effect is different: at 7 days (increase of hyaluronic acid and dermatan sulphate and decrease of chondroitin sulphate) and at 14 days (dermatan sulphate is not detectable).All the cells bind the Con A specifically, but a different pattern of agglutination is present in fibroblasts of the two embryonic ages. Since Con A is well known to bind carbohydrate-containing surface proteins, the result suggests that the release of GAG by chick embryonic fibroblasts can be modulated by cell surface receptors. 相似文献
14.
The temperature peak (15 °C) of acid and alkaline phosphatase in this study coincides with a peak in alpha-amylase as seen in an earlier study of roots of Verbascum thapsus. It is speculated that one of the results of higher phosphatase activities may be increased amount of orthophosphate which can be utilized in phosphorylation of soluble carbohydrates which in turn are in greater supply due to the higher activities of the starch-degrading enzymes.A second peak in activities of acid and alkaline phosphatase was seen in plants which were returned to the greenhouse following cold treatment. This increase in enzymatic activities is also similar to increases in activities of three starch degrading enzymes studied earlier. Alkaline phosphatase showed greater activities than did acid phosphatase at lower temperatures (10 and 4 °C) and under greenhouse conditions following cold treatment. 相似文献
15.
In this paper we describe properties of old (Takahashi, 1978) and new tabCts and tabCcs bacterial mutants. We find that under non-permissive conditions they differently inhibit the synthesis of specific T4 prereplicative gene products. Among such products, that we have been able to identify, are P43 and PrIIA. In contrast, P32 and PrIIB are not affected.Inhibition of P43 (T4 DNA polymerase) synthesis is sufficient to account for depressed DNA synthesis in tabC (Takahashi, 1978).In heterodiploids: (1) all tabC mutants are recessive; (2) all tabC mutants do not complement with each other; (3) at least one, tabCts-5521, becomes dominant at 42.6 °C if rho mutant ts15 (Tab+) (Das et al., 1976) is situated in trans; (4) tabCts-5521 also becomes dominant at 42.6 °C if tabCcs-110 and tabCcs-18 are situated in trans (42.6 °C is non-permissive for T4 development on tabCcs-5521 and permissive for T4 development on tabCcs mutants).We discuss the possibility that in tabC mutants rho protein is altered and insensitive to T4-specific anti-termination functions. We also discuss a model that accounts for the differential effect of tabC mutants on the synthesis of T4 prereplicative proteins. 相似文献
16.
S B Scholnick P A Caruso J Klemencic G S Mastick C Mauro M Rotenberg 《Developmental biology》1991,146(2):423-437
17.
U. Caruso B. Fowler M. Erceg C. Romano 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,562(1-2)
The concentration of very-long-chain fatty acids (VLCFA) (straight chain, more than 22 carbon atoms) in plasma or in cultured fibroblasts is one of the most important diagnostic criteria for the diagnosis of the peroxisomal disorders. A sensitive method for VLCFA assay in plasma, using small sample volume and a simplified procedure, is described. After adequate extraction and derivatization, methyl esters of VLCFA are separated, identificated and quantified by gas chromatography—mass spectrometry (GC—MS). The method is sensitive, reproducible, accurate and relatively simple. GC—MS equipment used for routine organic acid analysis can be used. 相似文献
18.
T Tancredi P A Temussi D Picone P Amodeo R Tomatis S Salvadori M Marastoni V Santagada G Balboni 《Biopolymers》1991,31(6):751-760
The message domain of dermorphin (Tyr-D-Ala-Phe), a natural mu-opioid heptapeptide, has long been considered the main cause of the high mu selectivity of this peptide and of its analogues. The recent discovery, in the skin of Phyllomedusa sauvagei (i.e., the same natural source of dermorphin) and of Phyllomedusa bicolor of deltorphins, challenges this belief. Deltorphins, in fact, are three heptapeptides characterized by a message domain typical of mu-selective peptides, but endowed of an extremely high delta selectivity, the highest of all natural opioid peptides. A conformational analysis of dermorphin and deltorphins, based on nmr studies in DMSO and cryoprotective mixtures and internal energy calculations, showed that the enormous differences in receptor selectivity can be interpreted on the basis of receptor models for mu and delta opioids that recognize the same beta-turn in the N-terminal part, but discriminate for the conformation and polarity of the C-terminal part. Here we present the synthesis, biological activity, and conformational analysis in solution of three deltorphin analogues with very similar constitution, but with different net charge, different location of negative residues, or even without negative residues, which confirm these hypotheses and show that His4 can play a specific structural role. 相似文献
19.
Conformational preferences of [Leu5]enkephalin in biomimetic media. Investigation by 1H NMR 总被引:2,自引:0,他引:2
D Picone A D'Ursi A Motta T Tancredi P A Temussi 《European journal of biochemistry》1990,192(2):433-439
The conformation of [Leu5]enkephalin has been studied by 1H-NMR spectroscopy in media more like the actual environment in which the agonist-receptor interaction takes place than water, i.e. in three cryoprotective mixtures (dimethylformamide/water, methanol/water and ethylene glycol/water), in aqueous SDS and in two neat solvents, dimethylformamide and acetonitrile, whose dielectric constants (36.7 and 37.5) are intermediate between that of water and that of the lipid phase. In all cases examined, contrary to the studies in water or dimethylsulfoxide, we were able to detect numerous nuclear Overhauser effects, indicating that the media employed favour well-defined structures and/or reduce the internal motions of the peptide. Data from both organic solvents and cryoprotective mixtures suggest a 4----1 beta turn as the most probable structure of [Leu5]enkephalin in solution, whereas in SDS/H2O micelles the structural picture appears completely different, suggesting the presence of a 5----2 beta turn. The existence of two different preferred conformations of enkephalins may possibly be related to their ability to be effective towards both mu and delta opioid receptors. 相似文献
20.
Thomas P. Caruso Dennis L. Larson Philip S. Portoghese A.E. Takemori 《Life sciences》1980,27(22):2063-2069
The nonequilibrium narcotic antagonist, chlornaltrexamine (CNA) was used to bind selectively and covalently pioid specific sites on brain membrane preparations. Selective binding of [3H]CNA occured with a saturation maximum of 185 fmol/mg protein. Bound [3H]CNA was extracted with Triton X-100, dialyzed against Brij 36T, precipitated with trichloroacetic acid and chromatographed on an ultrogel AcA 22 column. The elution profile suggests that this extract contains a minimum of four selective [3H]CNA complexes. At least two of these complexes migrate in a single large peak. Column calibration showed that this peak eluted at 590,000 daltons. One of these specific [3H]CNA complexes elutes at the elution volume of the column and is dialyzable. Finally, putative aggregate of these complexes elutes with the void volume. 相似文献