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61.
Inhibitory effects of clonidine on the allergen-induced wheal-and-flare reactions in patients with extrinsic asthma 总被引:2,自引:0,他引:2
Bjrn R. Lindgren M.D. Astrid Brundin M.D. Rolf G. G. Andersson Ph.D. 《The Journal of allergy and clinical immunology》1987,79(6):941-946
We investigated the possibility that clonidine, an alpha 2-adrenoceptor agonist, can reduce the wheal-and-flare reactions induced by intradermal injections of allergen in patients with extrinsic asthma. Ten adult subjects with asthma with positive skin tests to one or several pollens were selected. They received, in random order and double-blind manner, clonidine (two doses, each 75 micrograms) or placebo for 3 days, and then, after a 1-week washout period, they crossed over to the other treatment for 3 days. Treatment with clonidine reduced the area of wheal-and-flare reaction induced by allergen without significantly changing the blood pressure or the plasma cortisol level. There was a drop in the histamine content of leukocytes and in the number of eosinophils in peripheral blood after allergen challenge during the placebo treatment, whereas clonidine prevented these changes. The results suggest that treatment with clonidine can reduce the inflammatory reactions induced by allergens in subjects with extrinsic asthma. 相似文献
62.
Ralf Thomann Chun Wang Jrg Kressler Rolf Mülhaupt 《Macromolecular chemistry and physics.》1996,197(3):1085-1091
The formation of holes during the late stage of the isothermal crystallization in thin films of isotactic poly(propylene) between two cover glasses was observed by light microscopy and atomic force microscopy. This behavior can be described consistently by the well-known negative pressure effect. Light microscopy reveals the simultaneous and sudden occurrence of a large number of small holes at the liquid-solid interface after the liquid in front of the spherulites is completely confined by other spherulites for a certain time interval. In exceptional cases only a few holes appear and finally large cavities are formed. Atomic force microscopy measurements carried out in the height mode are able to prove the hole formation in front of the spherulites. Furthermore, a substantial thinning of the two-dimensional spherulites in thin films can be observed prior to the hole formation. 相似文献
63.
The effects of fish sera on the growth and fine structure of infective larvae of the eel-pathogenic acanthocephalanParatenuisentis ambiguus (Eoacanthocephala: Tenuisentidae) were studied under in vitro conditions using sera from the final hostAnguilla anguilla and from two accidental fish hosts as well as fetal calf serum. As controls larvae were also kept in medium in the absence of serum and in experimentally infected eels. Sera from the accidental fish hosts carp and rainbow trout exerted toxic effects on the acanthocephalans. Worms maintained in medium containing sera from these two fish were contracted and displayed inverted probosces. Moreover, the tegument exhibited vacuolization and the formation of necrotic areas, including lysis of the mitochondria. Due to these effects, the parasites died at 21 (rainbow trout) or 21–50 days (carp) postincubation. Eel sera had no toxic effect on the infective larvae. The growth of the larvae in medium depended on the composition of the latter, but was reduced as compared with that in the natural final host. Based on these results, we conclude that components of the hosts' blood sera play a role in the determination of the host specificity ofP. ambiguus. 相似文献
64.
Sander I Kespohl S Merget R Goldscheid N Degens PO Bruning T Raulf-Heimsoth M 《International archives of allergy and immunology》2005,136(1):39-44
BACKGROUND: Detection of allergen-specific IgE antibodies in patients' sera plays a key role for the diagnosis of IgE-mediated allergy. If no validated test system is available, diagnostic tools must be developed, usually by coupling or binding the allergens to a solid phase. Streptavidin ImmunoCAP is a new solid phase for binding of allergens which can be used in the Pharmacia CAP system. OBJECTIVE: It was the aim of this study to assess the diagnostic validity of Streptavidin ImmunoCAP. METHODS: Biotinylation and allergen concentration for binding to Streptavidin ImmunoCAP were optimized and IgE obtained with natural rubber latex, obeche wood, wheat and rye flour Streptavidin ImmunoCAP were compared with the results of ImmunoCAP and Enzyme Allergo-Sorbent Test (EAST) using sera from patients complaining of workplace-related respiratory symptoms. RESULTS: While the relation of biotin-label and protein was critical (best results were obtained with a 5- fold molar excess), labelled protein for coupling to streptavidin ImmunoCAP was applicable in a wide concentration range. On average, IgE values with streptavidin ImmunoCAP were as high as with ImmunoCAP but considerably higher than values obtained by EAST. CONCLUSION: Streptavidin ImmunoCAP is a valuable tool for sensitive and specific measurement of IgE binding to new allergens superior to cellulose disk-based methods. 相似文献
65.
Poly(propylene)s with narrow molecular weight distributions were prepared with various methylaluminoxane-activated metallocene-based Ziegler-Natta catalysts to study the influence of randomly incorporated regio- and stereoirregularities on the crystallization behavior. As a function of the metallocene type and the polymerization temperature, the molecular weights varied between 11500 < M n < 63 000, melting temperatures of annealed samples between 125 to 158°C, and the corresponding degrees of crystallinity, as measured by wide-angle X-ray scattering, between 49 and 67%. While the virgin poly(propylene)s exhibited exclusively the α-modification, annealing and melt crystallization favored the development of the γ-modification. The microstructure analysis by 13C NMR spectroscopy revealed a linear correlation between the content of the γ-modification and the average length of the isotactic segments. 相似文献
66.
Differences in assembly or stability of complex I and other mitochondrial OXPHOS complexes in inherited complex I deficiency 总被引:9,自引:0,他引:9
Ugalde C Janssen RJ van den Heuvel LP Smeitink JA Nijtmans LG 《Human molecular genetics》2004,13(6):659-667
NADH-ubiquinone oxidoreductase (complex I) deficiency is amongst the most encountered defects of the mitochondrial oxidative phosphorylation (OXPHOS) system and is associated with a wide variety of clinical signs and symptoms. Mutations in complex I nuclear structural genes are the most common cause of isolated complex I enzyme deficiencies. The cell biological consequences of such mutations are poorly understood. In this paper we have used blue native electrophoresis in order to study how different nuclear mutations affect the integrity of mitochondrial OXPHOS complexes in fibroblasts from 15 complex I-deficient patients. Our results show an important decrease in the levels of intact complex I in patients harboring mutations in nuclear-encoded complex I subunits, indicating that complex I assembly and/or stability is compromised. Different patterns of low molecular weight subcomplexes are present in these patients, suggesting that the formation of the peripheral arm is affected at an early assembly stage. Mutations in complex I genes can also affect the stability of other mitochondrial complexes, with a specific decrease of fully-assembled complex III in patients with mutations in NDUFS2 and NDUFS4. We have extended this analysis to patients with an isolated complex I deficiency in which no mutations in structural subunits have been found. In this group, we can discriminate between complex I assembly and catalytic defects attending to the fact whether there is a correlation between assembly/activity levels or not. This will help us to point more selectively to candidate genes for pathogenic mutations that could lead to an isolated complex I defect. 相似文献
67.
Thomas C. Baghai Peter Zwanzger Cornelius Schüle Christo Minov Stefanie Behrens Rainer Rupprecht Hans‐Jürgen Möller Rolf Engel Brigitta Bondy 《American journal of medical genetics. Part A》2002,114(5):530-532
Growing evidence suggests that G‐proteins may be involved in pathogenesis and treatment of affective disorders. Several studies have reported altered levels and/or activities of stimulatory G‐proteins in depression. The aim of this study was to investigate whether a polymorphism in the stimulatory α subunit of G‐proteins (T/C point mutation in exon 5; ATT → ATC at codon 131) is associated with major depression or response to antidepressant treatment. Therefore, we performed a case‐control association study with 212 depressive patients and 137 healthy, unrelated controls. There was no evidence for an association between the investigated polymorphism in the Gαs gene and major depression, as well as to treatment response. The results of our study are in concordance with recently published findings which do not support the hypothesis that the gene for the stimulatory α subunit of G‐proteins is a major susceptibility factor in the pathophysiology of major depression. © 2002 Wiley‐Liss, Inc. 相似文献
68.
Philipp Müller Christof Wrner Rolf Mülhaupt 《Macromolecular chemistry and physics.》1995,196(6):1917-1928
A novel family of functional ethene copolymers with various side chains were prepared by melt grafting of poly(ethene-co-methacrylic acid), containing 3,00 and 4,25 mol-% of methacrylic acid, with 2-substituted 1,3-oxazolines such as 2-phenyl-1,3-oxazoline, 2-undecyl-1,3-oxazoline, 2-heptadecyl-1,3-oxazoline, and 4-(1,3-oxazolin-2-yl)phenyl 4-methoxybenzoate. 1H NMR and FTIR studies of the polymer microstructures revealed that carboxylic acid groups reacted with 1,3-oxazolines within few minutes to form esteramide-coupled side chains in very high yields. Torque of the reaction mixture, mechanical and thermal properties of the graft copolymers were measured. In the case of 2-heptadecyl-esteramide-substituted polyethenes, the side-chain cocrystallization accounted for higher crystallinity of the resulting graft copolymers. 相似文献
69.
Philipp Müller Christof Wrner Rolf Mülhaupt 《Macromolecular chemistry and physics.》1995,196(6):1929-1936
2-Phenyl-1,3-oxazoline was injected into poly(ethene-co-methacrylic acid), containing 4,25 mol-% methacrylic acid units, at 225°C. In the first stage, 2-phenyl-1,3-oxazoline reacted with carboxylic acid groups to form esteramide side chains via grafting reaction. In the second stage, 2-phenyl-1,3-oxazoline containing methyl 4-nitrobenzensulfonate initiator was added to initiate in-situ cationic polymerization, yielding poly(N-benzoylethylenimine) as dispersed phase with 0,2–3,5 μm average diameter. Morphological, mechanical and thermal properties of poly-(ethene-co-methacrylic acid) blends, prepared by grafting combined with in-situ polymerization of 2-phenyl-1,3-oxazoline, were investigated. 相似文献
70.
Yi Thomann Friedrich G. Sernetz Ralf Thomann Jrg Kressler Rolf Mülhaupt 《Macromolecular chemistry and physics.》1997,198(3):739-748
A random ethene/styrene copolymer containing 13.8 mol-% styrene was prepared with the Ziegler-Natta catalyst system Me2Si(Me4Cp)(N-t-butyl)TiCl2/methylaluminoxane and characterized by means of preparative temperature rising elution fractionation (TREF) combined with size exclusion chromatography, NMR, differential scanning calorimetry and wide-angle X-ray scattering analyses of the copolymer fractions. Efforts are made to describe the distribution of the styrene content of the copolymers using the Stockmayer-Tacx distribution function. Both, comonomer distribution and molar mass distribution strongly support the presence of a single type of catalytically active center. 相似文献