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31.
Induction of accessory cell function of human alveolar macrophages by inhalation of human natural interleukin-2 总被引:1,自引:0,他引:1
Gernot Zissel Walter E. Aulitzky J. Lorenz Christoph Huber J. Müller-Quernheim 《Cancer immunology, immunotherapy : CII》1996,42(2):122-126
Accessory function allows antigen-presenting cells to produce sufficient secondary signals for optimum T cell proliferation
and interleukin-2 (IL-2) production. Alveolar macrophages are inferior accessory cells compared to monocytes (PBM). We report
here that the accessory index (AI) of alveolar macrophages and PBM of patients with lung metastases of solid tumors treated
with inhalations of human natural IL-2 (hnIL-2) increased following its administration (P<0.005). The accessory index was significantly elevated from baseline values after 2 weeks of inhalation of 300 000 IU hnIL-2/day
(8.2±10.2 compared to 1.1±1; P<0.001). The inhalation of 150 000 IU also induced increases in the index (AI = 2.3±1.9), however, without reaching statistical
significance. In addition at 300 000 IU IL-2/day a significant increase in the accessory index was observed for PBM (4±2.5;
P<0.05). The indices of PBM and alveolar macrophages prior to inhalation showed a significant negative correlation with the
age of the patients (r
s = – 0.5; r
s = – 0.8, respectively; P<0.03 for all comparisons). Our data demonstrate that the inhalational application of hnIL-2 enhances the accessory function
of alveolar macrophages and, to lesser extent, the accessory index of PBM, indicating the occurrence of pharmacological immunostimulation.
Received: 16 August 1995 / Accepted: 4 January 1996 相似文献
32.
33.
Christoph Meier Walter Senn Rudolf Hauser Manfred Zimmermanne 《Journal of mathematical biology》1994,32(6):563-572
The classical Nicholson-Bailey model for a two species host-parasitoid system with discrete generations assumes random distributions of both hosts and parasitoids, randomly searching parasitoids, and random encounters between the individuals of the two species. Although unstable, this model induced many investigations into more complex host-parasitoid systems. Local linearized stability analysis shows that equilibria of host parasitoid systems within the framework of a generalized Nicholson-Bailey model are generally unstable. Stability is only possible if host fertility does not exceede
4=54.5982 and if superparasitism is unsuccessful. This special situation has already been discovered by Hassell et al. (1983) in their study of the effects of variable sex ratios on host parasitoid dynamics. We discuss global behaviour of the Hassell-Waage-May model using KAM-theory and illustrate its sensitivity to small perturbations, which can give rise to radically different patterns of the population dynamics of interacting hosts and parasitoids. 相似文献
34.
Christoph Theurer Hans-Joachim Treumann Thomas Faust Ursula May Wolfgang Kreis 《Plant Cell, Tissue and Organ Culture》1994,38(2-3):327-335
The glycosylation and deglycosylation of cardiac glycosides was investigated using cell suspension cultures and shoot cultures, both established from Digitalis lanata EHRH. plants, as well as isolated enzymes. Shoots were capable of glucosylating digitoxigenin, evatromonoside, digiproside, glucodigitoxigenin and digitoxin. Suspension cultured Digitalis cells glucosylated all the substrates mentioned but digiproside, whereas the UDP-glucosedependent cardinolide glucosyltransferase isolated from that source did not accept digitoxigenin and digiproside as substrates. It is concluded that at least three different glucosyltransferases are involved in cardiac glycoside formation in Digitalis. Similar experiments carried out with glucosylated cardenolides which were administered to cultured cells, shoots and a cardenolide -glucosidase isolated from young leaves revealed that at least two different glucosidases occur in Digitalis lanata, albeit in different tissues or during different phases of development. The biotransformation of glucoevatromonoside was investigated using unlabelled compound and [14C-glucose]-glucoevatromonoside synthesized enzymatically. After 7 d of incubation almost no radioactivity could be recovered from the cardenolide fraction, indicating that the terminal glucose of glucoevatromonoside was now incorporated into volatile, hydrophilic and insoluble compounds. Since, on the other hand, large amounts of cardenolides were found in the experiments with unlabelled glucoevatromonoside it is assumed that steady state or pool size regulation is achieved by the coordinated action of a cardenolide glucosidase and a glucosyltransferase.Abbreviations Acdox
D-acetyldigitoxose
- dgen
digoxigenin
- dox
D-digitoxose
- dten
digitoxigenin
- dtl
D-digitalose
- fuc
D-fucose
- gten
gitoxigenin
- qun
D-quinovose
- CGH
cardenolide 16-O-glucohydrolase
- DFT
UDP-fucose:digitoxigenin 3-O-fucosyltransferase
- DGT
UDP-glucose:Digitoxin 16-O-glucosyltransferase
- DQT
UDP-quinovose:digitoxigenin 3-O-quinovosyltransferase 相似文献
35.
Indole-3-acetic acid (IAA), fusicoccin and weak acids all lower the cytoplasmic pH (pHi) and induce elongation growth of maize (Zea mays L.) coleoptiles. Gibberellic acid (GA3) also induces elongation growth and we have used confocal laser scanning microscopy to study the effects of GA3 on pHi employing the pH-indicator dyes, 2,7-bis(2-carboxyethyl)-5-(and-6) carboxyfluorescein and carboxy-semi-naphthorhodafluor-1. We confirm that GA3 induces growth significantly in light-grown but only slightly or not at all in dark-grown coleoptiles. The growth induced by IAA treatment was similar in light- and dark-grown coleoptiles. The pHi decreased by up to 0.6 units during the first 7 min of GA3 or IAA treatment of both light- and dark-grown coleoptiles. Gibberellic acid inhibited IAA-induced growth of dark-grown coleoptiles. Hence, in dark-grown coleoptiles GA3 may activate either directly or indirectly reactions that interfere with the signalling pathway leading to elongation growth. The possible role of pHi in growth is discussed.Abbreviations ABA
abscisic acid
- AM
acetoxymethyl ester
- BCECF
2,7-bis(2-carboxyethyl)-5-(and-6) carboxyfluorescein
- [Ca2+]i
cytoplasmic free calcium
- GA(n)
gibberellin A(n)
- GA3
gibberellic acid
- IAA
indole-3-acetic acid
- PGR
plant growth regulator
- pHi
cytoplasmic pH
- Pipes
piperazine-N,N-bis[2-ethanesulfonic acid]
- Snarf-1
carboxy-semi-naphthorhodafluor-1
We thank Dr R. King (CSIRO, Canberra) for providing the GA1 and T. Phillips for processing the photographic material. H.R. Irving was supported by an Australian Research Council Research Fellowship and the work was supported by an Australian Research Council grant. 相似文献
36.
Werner Landolt Madeleine Günthardt-Goerg Ilse Pfenninger Christoph Scheidegger 《Trees - Structure and Function》1994,8(4):183-190
Summary Cuttings of hybrid poplar (Populus × euramericana var. Dorskamp) were exposed to ozone (80 g/m3 from 2100 hours to 0700 hours, 180 g/m3 from 0700 hours to 2100 hours) for 3 months. Ozone reduced the starch content in leaves and stem bark, whereas starch granules accumulated in bundle sheath cells along small leaf veins. At the same time, sucrose and inositol content increased in the leaves. Mesophyll cells in the vicinity of the stomata were injured first, and droplet-like material appeared on their walls. In the sieve plates of fumigated trees, the pores showed a higher degree of narrowing than those of the control treatment. Cell collapse in the leaves was accompanied by water loss and an increase in air space. In the stems, the ozone treatment led to a reduced radial width, particularly in the xylem tissue. These results are discussed in relation to reduced or inhibited phloem loading and ozone-induced drought stress. The plants injured by ozone showed quite distinct patterns of metabolite responses as well as enzyme activities (PEP- and RubP-carboxylase) in the leaves from the top to the bottom. There were also remarkable differences in the reaction of sucrose and inositol between leaves and stem bark. Future research should therefore increasingly follow a whole-plant approach for a better understanding of complex plant reactions. 相似文献
37.
Uwe Ludewig Christoph Lorra Olaf Pongs Stefan H. Heinemann 《European biophysics journal : EBJ》1993,22(4):237-247
The members of the RCK family of cloned voltage-dependent K+ channels are quite homologous in primary structure, but they are highly diverse in functional properties. RCK4 channels differ from RCK1 and RCK2 channels in inactivation and permeation properties, the sensitivity to external TEA, and to current modulation by external K+ ions. Here we show several other interesting differences: While RCK1 and RCK2 are blocked in a voltage and concentration dependent manner by internal Mg2+ ions, RCK4 is only weakly blocked at very high potentials. The single-channel current-voltage relations of RCK4 are rather linear while RCK2 exhibits an inwardly rectifying single-channel current in symmetrical K+ solutions. The deactivation of the channels, measured by tail current protocols, is faster in RCK4 by a factor of two compared with RCK2. In a search for the structural motif responsible for these differences, point mutants creating homology between RCK2 and RCK4 in the pore region were tested. The single-point mutant K533Y in the background of RCK4 conferred the properties of Mg2+ block, tail current kinetics, and inward ion permeation of RCK2 to RCK4. This mutant was previously shown to be responsible for the alterations in external TEA sensitivity and channel regulation by external K+ ions. Thus, this residue is expected to be located at the external side of the pore entrance. The data are consistent with the idea that the mutation alters the channel occupancy by K+ and thereby indirectly affects internal Mg2+ block and channel closing.Abbreviations TEA
tetraethylammonium
- EGTA
Ethylene glycol-bis (-aminoethyl ether) N,N,N,N-tetraacetic acid
- 2S3B model
2-site 3-barrier model
Correspondence to: S. H. Heinemann 相似文献
38.
Summary Polyclonal antibodies were produced against the highly purified enzymes L-hydantoinase, hydantoin-racemase and L-N-carbamoylamino acid amidohydrolase of Arthrobacter aurescens DSM 3747. In order to exploit these antibodies for basic research (molecular biology) or bioengineering (process development), the serological properties had to be characterized. Both, the hydantoinase- and carbamoylase-antibodies were observed to be monofunctional, whereas the hydantoin-racemase-antibody was found to be additionally specific against the L-hydantoinase. Monospecificity was realized after affinity chromatography. Investigations on serological crossreactions with several linear- and cyclic amidases (e.g. hydantoinases) as well as hydantoin-racemases are demonstrated in this paper.Deticated to Prof. Dr. Klaus Mosbach on the occation of his 60th birthday. 相似文献
39.
Susanne Popp Anna Jauch Detlev Schindler Michael R. Speicher Christoph Lengauer Helen Donis-Keller Harold C. Riethman Thomas Cremer 《Human genetics》1993,92(6):527-532
The identification of marker chromosomes in clinical and tumor cytogenetics by chromosome banding analysis can create problems. In this study, we present a strategy to define minute chromosomal rearrangements by multicolor fluorescence in situ hybridization (FISH) with whole chromosome painting probes derived from chromosome-specific DNA libraries and Alu-polymerase chain reaction (PCR) products of various region-specific yeast artificial chromosome (YAC) clones. To demonstrate the usefulness of this strategy for the characterization of chromosome rearrangements unidentifiable by banding techniques, an 8p+ marker chromosome with two extra bands present in the karyotype of a child with multiple anomalies, malformations, and severe mental retardation was investigated. A series of seven-color FISH experiments with sets of fluorochrome-labeled DNA library probes from flow-sorted chromosomes demonstrated that the additional segment on 8p+ was derived from chromosome 6. For a more detailed characterization of the marker chromosome, three-color FISH experiments with library probes specific to chromosomes 6 and 8 were performed in combination with newly established telomeric and subtelomeric YAC clones from 6q25, 6p23, and 8p23. These experiments demonstrated a trisomy 6pter6p22 and a monosomy 8pter8p23 in the patient. The present limitations for a broad application of this strategy and its possible improvements are discussed.Dedicated to Professor Dr. U. Wolf on the occasion of his 60th birthday 相似文献
40.
Hubloher Josephine Joy Van der Sande Lisa Schaudinn Christoph Müller Volker Averhoff Beate 《International microbiology》2023,26(3):543-550
International Microbiology - Acinetobacter baumannii is an opportunistic human pathogen that has become a global threat to healthcare institutions. This Gram-negative bacterium is one of the most... 相似文献