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1.
Neugebauer  E.  Beckurts  T.  Lorenz  W.  Maroske  D.  Merte  H.  Horeyseck  G.  Dietz  W. 《Inflammation research》1986,18(1-2):23-29
The hypothesis of a causal relationship between a progressive and unrestrained increase of tissue histamine formation by activation of an inducible histidine decarboxylase (HDC) and lethality in endotoxic shock (Schayer's induced histamine concept) was tested in a standardized rat endotoxic shock model.Initial enzyme identification studies in the rat shock liver (8 hrs after endotoxin challenge) clearly demonstrate that the induced histidine decarboxylase is an acid (specific) HDC. The succeeding randomized, controlled study with appropriate inhibitors of the enzyme, -methyl-histidine (competitive inhibitor) and -fluoromethyl-histidine (irreversible inhibitor) using doses of 2, 20 or 100 mg/kg showedno significant effect on the survival rate of rats in endotoxin shock. The survival rate of the non-treated endotoxin control group (NaCl) was 25%; all methylprednisolone treated rats (50 mg/kg) survived.Thus, the induced histamine isnot a predominant factor (necessary or sufficient determinant) for the lethal outcome in rat endotoxic shock. The protective effect of MP isnot predominantly due to the inhibition of the induced histidine decarboxylase. The use of HDC-inhibitors as the appropriate instruments for evaluation of the significance of this mechanism is discussed.Clinic of General Surgery, City Hospital Sieburg.  相似文献   

2.
Pathogenic mechanisms that underlie feline leukaemia virus subgroup-C (FeLV-C) induced erythroid aplasia are unknown. FeLV-C infection is associated with higher serum levels of interferon- (IFN-) and tumour necrosis factor- (TNF-), which may act synergistically to cause haemopoietic suppression. In the present studies, the synergistic effects of TNF- and IFN- on feline bone marrow progenitors in vitro were evaluated. Bone marrow mononuclear cells from specific-pathogen-free cats were exposed to TNF- (100 and 200 pg/ml) and IFN- (100 or 200 units/ml), alone or in combination, for 2 h before plating for clonal assays of colony forming units. Our results show that TNF- and IFN- in combination caused marked suppression of feline colony forming units-erythroid (CFU-E), burst forming units-erythroid (BFU-E), and colony forming units-fibroblasts (CFU-F), whereas colony forming units-granulocyte/macrophage (CFU-GM) were minimally affected. The same concentrations of TNF- and IFN- alone had minimal effects on CFU-E, BFU-E and CFU-F. These results suggest that TNF- and IFN- may play a significant role in regulating haemopoiesis in cats and may be involved in the pathogenesis of erythroid aplasia in cats infected with feline leukaemia virus.  相似文献   

3.
Summary To find out whether 3-morpholino-sydnonimine (SIN 1), the active metabolite of molsidomine, exerts its antiaggregatory effects not only in vitro but also in vivo, we tested ex vivo aggregation before and after intravenous application of molsidomine in healthy volunteers. We also measured plasma levels of guanosine 35-cyclic monophosphate (cyclic GMP) as SIN 1, the bioactive metabolite of molsidomine, becomes effective via activation of soluble guanylate cyclase. In eight out of ten subjects molsidomine had an inhibitory effect on platelet aggregation and a higher threshold concentration of platelet-activating factor was required after molsidomine application to induce irreversible aggregation. Despite the effect on platelets, plasma cyclic GMP levels did not increase. These results suggest that the nitric oxide-containing SIN 1 inhibits platelet aggregation not only in vitro but also in vivo and that this property can be a beneficial effect in antianginal therapy.Abbreviations Cyclic GMP guanosine 35-cyclic monophosphate - NO nitric oxide - PAF platelet-activating factor - PRP platelet-rich plasma - SIN 1 3-morpholino-sydnonimine  相似文献   

4.
Gangliosides, sialic acid-containing glycosphingolipids, enhance tumor formation in experimental animals and are associated with tumor progression and metastasis in humans. The mechanism(s) for this activity is (are) unknown. One possibility is enhanced platelet activation, since the interaction of platelets with tumor cells contributes to tumor cell arrest in the vascular compartment. We have previously shown that neuroblastoma tumor gangliosides (NBTG) enhance platelet adenosine triphosphate (ATP) secretion, aggregation, and adhesion. We determined that these NBTG effects are specific for collagen and are mediated through an (( integrin-dependent mechanism. This report describes the effects of NBTG on a physiologically relevant model of collagen-( interaction. Platelet adhesion to immobilized native collagen fibers similar to those found in the extracellular matrix of blood vessels was determined. Platelet adhesion is enhanced by NBTG in a concentration-dependent manner. Incubation with concentrations of 1 and 10 m NBTG increased platelet adhesion by 9% and 52%, respectively, compared to less than 1% in controls not incubated with gangliosides (P = 0.001 and P < 0.0001, respectively). In addition to increasing the number of adherent platelets, NBTG promoted more rapid attachment. In NBTG-incubated platelets, platelet adhesion began after a 5-min lag phase and was maximal at 30 min compared to a 20-min lag phase and maximal adhesion at 60 min for control platelets. At 30 min this difference was significant (P = 0.017); however, by 120 min there was no difference between NBTG and controls (P = 0.259). NBTG also induces platelet adhesion at collagen concentrations (0.1 g) that failed to support adhesion of control platelets. These effects of NBTG require Mg or Mn ions but are not supported by Zn or Ca ions. Furthermore, preincubation of platelets with a blocking antibody (6F1) to the integrin collagen receptor ( abrogates all of the effects of NBTG. These results indicate that tumor gangliosides enhance platelet adhesion to extracellular matrix collagen and promote rapid stabilization of the collagen-(( interaction, the initial steps in platelet activation.  相似文献   

5.
The chemokines are members of a bipartite superfamily of soluble proteins that have been implicated in a wide range of acute and chronic inflammatory processes, as well as other immunoregulatory functions. Macrophage inflammatory protein-1 alpha (MIP-1) belongs to the C-C subfamily of these chemokines and is primarily a potent chemoattractant and activator of monocytes. MIP-1 is also thought to play a role in host defence. We examined the expression of MIP-1 in normal lung, inflammatory lung tissue and lung cancer cells by the immunoperoxidase method using a MIP-1 monoclonal antibody. MIP-1 protein was found to be expressed not only by alveolar macrophages, but also by bronchial ciliated cells, hyperplastic alveolar type II cells and activated fibroblasts surrounding malignant tissue. Of 33 cases of lung cancer, 23 (70%) expressed MIP-1. These observations suggest that lung cancer cells, non-neoplastic alveolar type II cells and fibroblasts can participate in inflammatory cell recruitment via the production of MIP-1. Tumour derived MIP- may also affect the interaction between lung cancer and host inflammatory cells.  相似文献   

6.
We have identified a recessive -mating-type-specific gene agl causing agglutinability defect without significant effects on other sexual activities. a cells carrying agl showed sexual agglutination with cells but cells carrying agl showed sexual agglutination with neither cells nor a cells. cells carrying agl produced pheromone and responded to a pheromone just like wild cells. cells carrying agl showed a little decreased but significant mating ability when tested on solid media or membrane filter. The agl mutant is different from any -specific ste mutants found so far in many sexual activities. The agl gene is recessive, and unlinked to the mating type locus. Biological significance of the mating type agglutinability is discussed based on the results obtained with the mutant.  相似文献   

7.
The structural relation of YOP-1 of european and american Yersinia enterocolitica serotypes O3, O9, O5, 27, and O8 and O20, respectively, and Y. pseudotuberculosis serotypes I, II, and III was compared by sodium dodecyl sulfate polyacrylamide gel electrophoresis and peptide mapping using Staphylococcus aureus protease V8. Apparent molecular weights of YOP-1 ranged from 206,000 (O3) to approx. 180,000 (O8). According to their respective peptide maps YOP-1 of the european and american Y. enterocolitica serotypes and Y. pseudotuberculosis serotypes could be assigned to three different groups. Evaluation of several isolates of Y. enterocolitica serotypes O3, O9, and O8 by peptide mapping indicated that YOP-1 is conserved within a serotype. However, one serotype O8 isolate differed from the consensus peptide pattern of the other serotype O8 and O20 isolates. The similarity of the peptide patterns of Yersinia serotypes which predominate in certain geographical locations, i. e., european and american Y. enterocolitica serotypes, suggest common evolution of YOP-1 of these serotypes independent of the evolution of the other serotypes.  相似文献   

8.
Endothelial cells play an important role in adhesive interactions between circulating cells and extracellular matrix proteins. In vitro studies have shown that many of these processes are mediated by a superfamily of heterodimeric transmembrane glycoproteins called integrins. The distribution patterns of 1, 3 and 4 integrin subunits in endothelial cells (EC) in situ were examined immunohistochemically on serial forzen sections of a wide range of non-neoplastic tissues and of vascular tumours, both benign and malignant. Expression of the 1 subunit was a constitutive feature of EC. Among the 1-associated subunits, 5 and 6 were broadly distributed in EC, irrespective of vessel size and microenvironment. The 3 subunit displayed intermediate levels of expression with a slight preference for small vessel EC. Presence of 1 was confined to EC of capillaries and venules/small veins. Expression of 2 in EC was inconsistent. With rare exceptions, the 4 chain was absent in EC. The 3 and v subunits were expressed in most EC, though not always concomitantly. In contrast to the 1 chain, however, these integrin subunits were absent in EC of glomerular capillaries and were expressed variably in sinusoidal EC. The 4 chain was evenly present in the great majority of EC, except for those of large vessels. In vascular tumours, the patterns of 1 and 1 to 6 subunit expression generally corresponded to those found in their non-neoplastic counterparts. Expression of 3, v and 4 chains, however, decreased in neoplasia, especially in angiosarcomas. These data show that EC dispose of broad and at the same time differential repertoires of integrin subunits that presumably reflect vessel-type associated functional differences among these cells. In vascular tumours, the orthologous distribution patterns of 1 and 1 to 6 chains are conserved in most instances while the amounts of 3, v and 4 subunits expressed in EC tend to decrease in the course of malignant transformation.Dedicated to Prof. Dr. med. Dres. h.c. Wilhelm Doerr on the occasion of his 80th birthday  相似文献   

9.
Rho proteins participate in the regulation of inflammatory gene expression in endothelial cells. We made use of Clostridium difficile toxin B-10643 (TcdB-10463) which inhibites RhoA/Rac1/Cdc42 to analyze their role in expression and regulation of cyclooxygenase-2 (COX-2) in endothelial cells (EC). Pretreatment of EC with TcdB-10643 prevented lipopolysaccharide (LPS)- or tumor necrosis factor- (TNF )-related COX-2 expression but had no effect on COX-1 protein levels. TcdB-10463 preincubation suppressed LPS-dependent nuclear factor-B activation (NF- B). Rho inhibition did not affect COX-1 activity. Inactivation of Rho proteins before LPS stimulation blocked arachidonic acid (AA)-, thrombin-, and Escherichia coli hemolysin (HlyA)-dependent release of COX-2-related 6-ketoprostaglandin F1 (6k-PGF1). In contrast, Rho inhibition did not affect COX-2-dependent 6k-PGF1 liberation when TcdB-10643 was added 10 h after LPS or TNF stimulation of EC. Therefore, RhoA/Rac1/Cdc42 contribute to NF- B-dependent LPS- and TNF-induced expression of PGHS-2 in EC but had no effect on the activity of expressed COX-1 and COX-2.  相似文献   

10.
Chemokines are important inflammatory mediators that function by activating and recruiting leukocytes to an inflamed tissue. We have recently cDNA cloned the rat chemokine macrophage inflammatory protein–1 (MIP-1) (1). In the present study, we characterize the biological function of recombinant MIP-1 protein and describe expression of its mRNA both in vitro and in a rat model of lung inflammation. In vitro rat rMIP-1 protein was chemotactic for both polymorphonuclear leukocytes (PMNs) and macrophages with maximal activity at 50 nM for both cell types. In in vivo studies, we found that intratracheal instillation of 1 and 5 g of rMIP-1 resulted in a significant (P < 0.05) influx of cells, primarily monocytes/macrophages, into the airspace of the lungs after 6 h. Mean numbers of lavagable PMNs were not elevated significantly (P < 0.05) for either dose of MIP-1. As a model of inflammation, rats were intratracheally instilled with 0.1 mg/kg bacterial lipopolysaccharide (LPS). Bronchoalveolar lavage (BAL) was performed 3 h later. Instillation of LPS resulted in an acute neutrophilia, but no significant change in lavagable macrophages. BAL cells from control animals (saline instilled) displayed no basal mRNA expression of either MIP-1 or MIP-2 (positive control). In contrast, both MIP-1 and MIP-2 mRNA levels increased markedly in BAL cells from rats instilled with LPS. The rat alveolar macrophage cell line (NR8383) also showed increased MIP-1 mRNA levels in response to LPS (10 g/ml) with a maximal increase after 6–8 h. The induction of MIP-1 mRNA expression by LPS in NR8383 cells was attenuated by cotreatment with the antioxidants N-acetylcysteine and dimethylsulfoxide, suggesting that the induction of MIP-1 mRNA by LPS is mediated via the generation of reactive oxygen species. We conclude that MIP-1 is a potent chemoattractant for macrophages in vivo, and its mRNA expression in macrophages and BAL cells in response to inflammatory stimuli suggests a fundamental role in acute pulmonary inflammation.  相似文献   

11.
Immune-aggregate and thrombin-mediated [3H]serotonin release from human platelets are shown to be enhanced when platelets are preincubated with the antibacterial chymotrypsin-like cationic protein isolated from human granulocytes. The enhancement is dose dependent and inhibited by heating of the cationic protein. Release with chymotrypsin-like cationic protein alone was not observed, although the protein was shown to micro-aggregate platelets irreversibly by an ADP-dependent reaction. Platelet macro-aggregation induced by immune-aggregate was also enhanced by chymotrypsin-like cationic protein whereas platelet macro-aggregation induced by thrombin was inhibited competitively. Platelet micro-aggregation induced by chymotrypsin-like cationic protein was inhibited when preincubated for more than 5 min with a 2-fold molar excess of-1-antitrypsin. Chymotrypsin-like cationic protein interaction with several platelet reactions suggests a close relationship between neutrophils and platelets in the inflammatory process.  相似文献   

12.
    
Summary In an electron-microscopical study the occurrence and ultrastructural features of electron-dense dark variants of pinealocytes were evaluated in the gerbil pineal gland. A few dark pinealocytes, which tended to form small clusters of contiguous cells, could consistently be detected in pineals fixed and embedded by various procedures. Apart from the different degree of electron density, the only conspicuous difference between dark and electron-lucent light pinealocytes concerned their compartment of synaptic-like microvesicles. Thus, both variants of pinealocytes contained abundant clear microvesicles of variable size which accumulated in dilated process terminals. However, the vesicles within the process endings of dark pinealocytes showed an unusually dense arrangement throughout the cytoplasm. As was demonstrated by immunogold staining, the accumulations of vesicles in the dark terminals contained synaptophysin, a major synaptic vesicle-associated protein. This protein is present in small clear vesicles with putative secretory functions in a wide variety of neuroendocrine cells and has previously been shown to be a common constituent of microvesicles in mammalian pinealocytes. Since gerbil pinealocytes displayed distinct gradations of electron density, their ultrastructural heterogeneity may be the expression of different states of secretory activity of one pinealocyte cell type. On the other hand, differences in the content of synaptic-like microvesicles in the process terminals of light and dark cells could also indicate a principal functional heterogeneity of the microvesicular compartment among pinealocytes, pointing to the existence of different types of pinealocytes.  相似文献   

13.
Summary Earlier studies concerning 1 gene regulation by the 4 protein, the major regulatory protein of herpes simplex virus 1 (HSV-1), in stably transformed cell lines, reported conflicting results, i.e., 4 protein positively regulated the 1 gB gene in 4/gB cells, while it negatively regulated the 1 gD gene in 4/BJ cells. Both cell lines were derived from a common parental cell line 4/c 113 that contains 1 copy of the 4 gene, and the only apparent difference between them was the relative copy number of the gB and gD sequences (1 and 30–50, respectively) resident in the cell genome. We investigated this disparity by constructing a cell line (BA 4) that contains one copy each of the 4 and 1 gD sequences, by fusion of 4/c 113 and BJt cells, containing and expressing respectively 1 copy of the 4 and gD genes. BA 4 cells constitutively expressed both the 4, gD genes inherited from the parental cell lines ( 4/c 113 and BJt). In BA 4 cells the 4 protein positively regulates the gD gene as evidenced from (i) higher levels of gD expression than the parental BJt cells lacking the 4 gene, and (ii) significant decrease in gD expression under conditions that render the 4 protein produced in BA 4 cells non-functional. In addition the 2gG gene contained within the DNA fragment encoding the gD gene, is also expressed in BA 4 cells. On the basis of these data, we propose that gene regulation by the 4 protein is affected by the relative copy number of these genes, resident in the cell genome.  相似文献   

14.
Summary Fully differentiated kinetes, average length 17.6m, appeared in the haemolymph of engorged nymphs usually 17 to 20 days after repletion. Kinetes were observed at first in the salivary glands on day 18 after repletion. The kinetes then transformed into fission bodies of about 10m in diameter, mainly in type III alveoli and less frequently in type II alveoli. The fission bodies grew up to a size of about 20m after several divisions of their nucleus. At this time the ticks moulted and no further development occurred until activation. Shortly before infestation the salivary glands began to proliferate, and rapid growth of the fission bodies was observed, especially in young ticks where development of infective particles (sporozoites) was concluded within two days. Development in feeding adult ticks apparently occurred in four major steps: (1) Division of primary fission bodies (sporonts) into numerous secondary fission bodies (primary sporoblasts), (2) division of secondary fission bodies into tertiary fission bodies (secondary sporoblasts), (3) production of particles (sporozoites) by tertiary fission bodies and release of particles into the saliva, and (4) degeneration of fission bodies and their host cell but further release of particles.The host cell was stimulated to giant growth, thus its diameter increased, on average, from 15 to 110 m. Heavy infections resulting from parasitaemias of >40% caused disease and mortality in the tick population. Development was much retarded by aging. In ticks starved for six months sporozoites did not develop before day five to seven of infestation. Sporozoites may not develop at all in six to nine month old female ticks during the infestation period. The significance of the described developmental stages ofT. annulata was discussed and a sexual generation postulated. The hypothetic development ofT. annulata in its tick vector was illustrated.

Gefördert von der Deutschen Forschungsgemeinschaft (DFG)  相似文献   

15.
Bacterial meningitis is accompanied by an acute inflammatory response which may be exacerbated by antibiotic treatment and subsequent killing of bacteria. Bacterial cell products induce the release of cytokines including TNF, which contribute to the inflammatory process. Alpha-1-acid glycoprotein (AAG), an acute phase reactant, is elevated during inflammation. To test whether AAG has anti-inflammatory activity we examined its effect on lipopolysaccharide-stimulated human peripheral blood mononuclear cells. Treatment of the cells with AAG in vitro resulted in reduced TNF production. To test the effects of the molecule in vivo, AAG was administered intrathecally to rabbits with Haemophilus influenzae B lysate induced meningitis. Human AAG reduced TNF production and leukocytosis in the cerebrospinal fluid. Histopathology of the leptomeninges showed markedly attenuated inflammation. These results indicate that AAG can reduce inflammation in rabbits with experimental meningitis and that the effect may be directly on TNF production by stimulated mononuclear leukocytes.  相似文献   

16.
We have investigated the ability of rat and rabbit leucocytes to generate coagulant activity (PCA) in response to endotoxinin vitro andin vivo. On prolonged incubation with endotoxin (10 g/ml f.c.) isolated rabbit leucocytes developed strong PCA as measured by clotting and amidolytic assay. In constrast, rat leucocytes failed to produce any PCA even in the presence of huge amounts of endotoxin (200 g/ml f.c.). When rabbits were given two spaced endotoxin injections (25 g/kg b.w., 24 h apart) blood leucocytes harvested 30–60 min after the second injection consistently showed marked PCA. Again, unlike the rabbit, rat leucocytes obtained after two endotoxin injections (up 2 mg/kg b.w.) were completely devoid of PCA. These findings support the view that leucocytes are involved in endotoxin-induced disseminated intravascular coagulation in rabbits. On the other hand the poor response of rat leucocytes to endotoxin might help explain the resistance of rats to DIC and Sanarelli-Shwartzman reaction.  相似文献   

17.
Zusammenfassung Nach einer Literaturübersicht wird das Vorkommen der seltenen Rh-Genotypen rr und rr in 2 Generationen einer deutschen Familie beschrieben.  相似文献   

18.
Extracellular phospholipase A2 activity has been detected in caseinate-induced peritoneal fluid in rats. We studied the source of this extracellular phospholipase A2 in platelet-poor rats which had been pretreated with an intravenous injection of rabbit anti-rat platelet serum. In these rats, the increase in the peritoneal fluid extracellular phospholipase A2 level at the inflamed sites was almost identical to that observed in control rats, although platelet numbers in peripheral blood were decreased markedly. This observation suggests that extracellular phospholipase A2 in the peritoneal cavity is not derived mainly from platelets.This work was supported in part by Grants-in-Aid for Scientific Research (Nos. 62870093 and 63480490) from the Ministry of Education, Science and Culture of Japan.  相似文献   

19.
Summary Mechanisms of resistance to beet necrotic yellow vein virus (BNYVV) were studied by comparing the multiplication and distribution of BNYVV in root tissue of some beet accessions. Seedlings were infected either by soil containing resting spores ofPolymyxa betae with BNYVV, or by a viruliferous zoospore suspension. With both inoculation methods high virus concentrations were obtained in rootlets of the susceptible cultivar Regina. Using infested soil, low virus concentrations were found in the partially resistant cultivar Rima and in the resistant accessions Holly and WB42. When a zoospore suspension was used, similar virus concentrations occurred in Rima and Holly as in Regina, while a low virus concentration was found in WB42. By in situ localisation studies, using immunogold-silver labelling, virus was detected in Regina after infection by soil or a zoospore suspension, but it could only be detected in the resistant accessions after infection by a zoospore suspension. In rootlets of Regina, Rima and Holly, virus was found in the epidermis, cortex parenchyma, endodermis, and interstitial parenchyma, but in general not inside the vascular tissue. In WB42 the virus, occurring in small aggregates, seemed to be restricted to the epidermis and some cortex parenchyma cells. Comparing both the multiplication and distribution of BNYVV in rootlets of the accessions studied, it is concluded that the virus resistance mechanism in Rima and Holly is different from that in WB42.  相似文献   

20.
Summary The investigation of in vitro platelet functions from patients with SLE and rheumatoid arthritis (RA) revealed a distinctly reduced aggregation mass after both collagen und ADP induction. The platelet serotonin contents were significantly decreased in both groups. An aspirin-like platelet defect could be excluded by finding a normal malonyldialdehyde release of patients' platelets upon thrombin stimulation. Significantly increased platelet associated IgG was also detected, whereas platelet associated IgM remained within normal limits. These results are interpreted as indicating an ongoing platelet release reaction induced by IgG platelet antibodies, which induce the observed impairment of platelet functions and may also lead to the release of proinflammatory platelet mediators.

Abkürzungsverzeichnis ACD ACD-Lösung nach USP-Formel A (Dextrose 2,45 ng; Natriumcitrat 2,2 g; Zitronensäure 0,8 g; Aqua bidest ad 100,0) - ADP Adenosindiphosphat - ATP Adenosintriphosphat - -TG -Thromboglobulin - cP chronische Polyarthritis (rheumatoid arthritis) - ELISA enzyme-linked immunosorbent assay - MDA Malonyldialdehyd - PRP platelet rich plasma (thrombozytenreiches Plasma) - PPP platelet poor plasma (thrombozytenarmes Plasma) - SLE systemischer Lupus erythematodes - TAIgA Thrombozyten-assoziiertes IgA - TAIgE Thrombozyten-assoziiertes IgE - TAIgG Thrombozyten-assoziiertes IgG - TAIgM Thrombozyten-assoziiertes IgM - Thr Thrombozyten Mit Unterstützung der Deutschen Forschungsgemeinschaft, SFB 54-G3  相似文献   

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