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1.
Ulrich Weser Karl-Heinz Sellinger Edmund Lengfelder Walther Werner Joachim Strähle 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,631(2):232-245
The copper complex of indomethacin (1-(p-chlorobenzoyl)-5-methoxy-2-methyl-indole acetate), a common anti-inflammatory drug, was prepared and characterized. Crystal structure determination revealed the dimeric form of the 1:2 complex, namely Cu2(indomethacin)4 · L2, in the unit cell. Suprisingly, the copper-copper distance (263 pm) was very close to metallic copper (256 pm). The two coordination sites in the copper-copper axis can be readily replaced by superoxide. An intriguing similarity to Cu2(acetate)4 was seen.Due to the lipophilic nature of the indomethacin ligand, this copper complex reacted with superoxide in aprotic solvents. The superoxide dismutating activity was successfully demonstrated in Me2SO/water and acetonitrile/water mixtures using the nitro-blue tetrazolium assay and pulse radiolysis. The second-order rate constant of 6 · 109 M?1 · s?1 in strictly aqueous systems dropped only slightly to 1.1 · 109 M?1 · s?1 when aprotic solvents were used. This is the fastest rate constant ever observed for a copper-dependent dismutation of superoxide. The KO2-induced lipid peroxidation in both erythrocytes and liver microsomes was suppressed by 70% in the presence of 1 · 10?10 mol · ml?1 of Cu2(indomethacin)4. The inhibitory action dropped to 25% when Cu2Zn2superoxide dismutase was employed. The formation of copper · indomethacin in rat serum after administration of indomethacin was shown in vitro and in vivo. 相似文献
2.
Reinhard Lakes Klaus Kalmring Karl-Heinz Engelhard 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1990,166(4):553-563
Deafferentation experiments during postembryonic development show morphological and/or physiological changes of receptor fibers and of identified auditory interneurons in the CNS of the locusts Locusta migratoria and Schistocerca gregaria after unilateral ablation of one tympanic organ either in the larva or the adult animal.
相似文献
1. | In Locusta migratoria, 5 days after deafferentation, intact, contralateral receptor fibers had sprouted collaterals in the frontal acoustic neuropil of the metathoracic ganglion (Figs. 1, 2). Collateral sprouts were only rarely found in Schistocerca gregaria. |
2. | After about 20 days the deafferented auditory interneurons receive new inputs from the contralateral receptors (Figs. 3, 5, 7, 10). This largely restores their thresholds and intensity/response functions. Collaterals from the first order interneurons cross the midline to the contralateral neuropil (BSN1 neuron, Fig. 4), which is never seen in intact animals. By contrast, in the TN1 neuron no consistent morphological change due to the deafferentation could be found (Fig. 6). |
3. | Interneurons of higher order (AN1, TN3 neuron in locusts) regain their response pattern (Fig. 7) without morphological changes (Fig. 9). Bilateral recordings show that the deafferented interneurons respond more weakly to auditory stimuli than the intact neuron, but the response to vibration stimuli remains unchanged (TN3 neuron, Fig. 8). |
3.
Jacques Simard Dominique Bérubé Märten Sandberg Karl-Heinz Grzeschik Richard Gagné Vidar Hansson Tore Jahnsen 《Human genetics》1992,88(6):653-657
Summary A cDNA for the human catalytic subunit (C) of cAMP-dependent protein kinase (PKA) has been cloned from a testis cDNA library. In the present study, we have determined the chromosomal localization of this gene using a cDNA for C as a probe. Southern blot analysis of genomic DNA from human/mouse cell hybrids revealed that the presence or absence of a 20-kbXbaI fragment, which hybridized with the C probe, was concordant with the presence of human chromosome 1.In situ hybridization to metaphase chromosome confirmed the somatic cell hybrid data and regionally mapped the C gene of PKA to the p36 band on chromosome 1. 相似文献
4.
Michael I. Lerman Farida Latif Gladys M. Glenn Lambert N. Daniel Hiltrud Brauch Shigeto Hosoe Krista Hampsch John Delisio Mary Lou Orcutt O. Wesley McBride Karl-Heinz Grzeschik Takashi Takahashi John Minna Patrick Anglard W. Marston Linehan Berton Zbar 《Human genetics》1991,86(6):567-577
Summary A collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies. 相似文献
5.
Summary Five bird species were examined in order to ascertain if any changes in flight muscle catabolism take place between breeding season and migration. Two different patterns were discovered. The first consists of a high oxidative capacity and a low glycolytic and anaerobic capacity during migration. The converse occurs during the breeding season, i.e. low oxidative, high glycolytic and anaerobic capacity. The pattern was found in those species that deposit large amounts of fat prior to migration. The second pattern was similar to the first, but there was no change in fatty acid oxidation capacity between breeding season and migration. The pattern was found in those species that do not deposit much fat towards migration. These changes are believed to reflect differences in migration strategy and differences in locomotory activity during different seasons. Deviations from these patterns are discussed. 相似文献
6.
7.
Methanobacterium thermoaggregans is a new thermophilic autotrophic rod-shaped methane producing bacterium. The organism likes to form aggregates during growth and utilizes only H2 and CO2 as substrates. Growth optimum is at 65°C with a doubling time of 3.5 h. Optimal growth occurs at pH-values between 7 and 7.5. The addition of yeast extract to the mineral salt medium stimulates growth. The DNA base composition is 42 mol% G+C. The organism was isolated from mud taken from a cattle pasture. Because of its optimal growth temperature and its tendency to form aggregates the nameMethanobacterium thermoaggregans is suggested.Abbreviations G+C
Guanine+cytosine 相似文献
8.
Achim Recktenwald Karl-Heinz Kroner Maria-Regina Kula 《Enzyme and microbial technology》1985,7(12):607-612
Flow injection analysis (FIA) has been employed to automate enzyme assays for formate dehydrogenase (FDH) and l-leucine dehydrogenase (l-LeuDH). Coupled to a special sampling device the FIA assays were used to monitor on-line downstream processes, e.g. disintegration of microbial cells and cross-flow filtration of cell homogenates. 相似文献
9.
Karl-Heinz Schmidt 《Journal of Ornithology》1984,125(3):321-331
Zusammenfassung Die jährlichen Schwankungen im Legebeginn bei Kohl-, Blau-, Sumpf- und Tannenmeisen sind mit den Frühjahrstemperaturen (Wärmesummen) korreliert. Für KM, BM und SM sind die Wärmesummen in einem 4-Wochen-Zeitraum — Mitte März bis Mitte April — ausschlaggebend. Für TM sind lediglich die Wärmesummen von 2 Wochen — Anfang bis Mitte April — entscheidend. Die Wirksamkeit von Temperaturen in 4- bzw. 2-Wochen-Zeiträumen vermag auch zu erklären, warum KM, BM und SM alljährlich ähnliche Zeitverschiebungen im Legetermin zeigen, TM hingegen die geringste Übereinstimmung mit den anderen Meisenarten besitzen. KM, BM und SM reagieren erst, wenn Frühjahrstemperaturen die 6°C- oder 8°C-Schwelle überschreiten. TM scheinen auch auf niedrigere Temperaturen anzusprechen. Der Laubaustrieb von Buchen, Fichten und Stieleichen wird durch Frühjahrstemperaturen (Wärmesummen) stark beeinflußt. Fichten und Eichen reagieren besonders stark auf Temperaturen von Anfang bis Mitte April, Rotbuchen am stärksten von Mitte März bis Mitte April. Die höchsten Korrelationen ergaben sich bei der 6°C- und 8°C-Schwelle. Zwischen Legebeginn und Laubausbruch von Buchen und Fichten besteht ein statistisch gesicherter Zusammenhang. Der Laubaustrieb von Eichen ist bei 3 von 4 Meisenarten nicht mit der Eiablage korreliert. Eine Steuerung der Eiablage durch den Anblick frisch ausgetriebener Blätter ist auszuschließen. Der Eiablagebeginn der Meisen scheint am besten mit dem Laubaustrieb der jeweils häufigsten Baumart in einer bestimmten Region synchronisiert zu sein.
Spring temperature and time of laying in tits
Summary The yearly variations in the start of laying by Great Tits(Parus major), Blue Tits(P. caeruleus), Marsh Tits(P. palustris) and Coal Tits(P. ater) are correlated with the spring temperatures (heat sums). The heat sums over a period of 4 weeks from mid March to mid April are of crucial importance for Great Tits, Blue Tits and Marsh Tits, whereas for Coal Tits only the heat sums of the 2 weeks from the beginning to the middle of April are decisive. The influence of temperature during 4 or 2 week periods, also explains why Great Tits, Blue Tits and Marsh Tits show similar variation in laying dates every year, whereas Coal Tits show the lowest correlation with other species of tits. Great Tits, Blue Tits and Marsh Tits only react to spring temperatures exceeding 6°C or 8°C. Coal Tits also seem to be susceptible to low temperatures. Beech(Fagus sylvatica), pine(Picea abies) and oak(Quercus robur) leafing is greatly influenced by spring temperatures (heat sums). Pine and oak react especially strongly to temperatures from the beginning to the middle of April. Temperature influence on beech leafing is most pronounced from mid March to mid April. The highest correlations occurred at the 6°C and 8°C threshold. There is firm statistical evidence of a connection between the 4 tit species' timing of laying and beech and pine leafing. Oak leafing is not correlated with the egg laying of 3 of the 4 tit species. The possibility that the sight of freshly opened leaves triggers egg laying must be ruled out, as tits start laying, with a few exceptions, before leafing starts. The start of laying seems for the tits to be best synchronized with the leafing of the most prevalent type of tree in a particular region.相似文献
10.
Summary Voltage-clamped single nerve fibers of the frogRana esculenta were treated with the carboxyl group activating reagent N-ethoxy-carbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) in the presence of different primary amines and without added amine. Carboxyl groups form stable amide bonds with primary amines in the presence of EEDQ. EEDQ treatment reduced the sodium current considerably and irreversibly, regardless of the presence of a primary amine in the Ringer's solution. The potassium current was also reduced. After modification the reduced sodium currents inactivated slowly and incompletely. The descending branch of the sodium current-voltage relation,I
Na(E), was shifted along the voltage axis in the depolarizing direction. The size of the shift was strongly dependent on the amine present during modification with EEDQ. The voltage-dependence of sodium inactivation,h
x
(E), was shifted to more positive values of membrane potential by EEDQ in the presence of ethylenediamine (11 mV) and glucosamine (3 mV). In contrast, a small shift to more negative potentials occurred in the presence of taurine (–3 mV) or without the addition of an amine (–2 mV). A tenfold increase of the calcium concentration still shifted theI
Na(E) andh
x
(E) curves of the chemically modified fibers. However, these shifts were smaller than those observed on untreated fibers. The currents remaining after the modification were completely blocked by tetrodotoxin; no change of the reversal potential occurred. 相似文献