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T Andus

Publications and source records attributed to T Andus.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Crohn disease: prevention and drug therapy].

In view of a high recurrence rate of Crohn's disease after surgical resection prophylaxis is desirable. The value of various medical therapies to maintain remission after surgery has thus far only partially been established in clinical trials. Therefore, no clear guidelines are presently available. In patients with complete resection and a low risk of recurrence prophylactic treatment seems not to be necessary. In patients with a high risk of recurrence prophylactic treatment is recommended. This recommendation is supported by some clinical trials, although major trials are still ongoing. 5-Aminosalicylic acid in a daily dose of ca. 2-3 g is the primary choice for prophylaxis of recurrence. It reduces the risk of recurrence presumably by about 50%. In patients with a complicated course of the disease who have undergone several previous resections immunosuppressive treatment with azathioprine (1-2 mg/kg body weight/day) is recommended to avoid further recurrences. Conventional corticosteroids are not effective for postoperative prophylaxis. Ongoing studies evaluate the non-systemic steroid budesonide as prophylactic treatment. There is no specific nutritional therapy to prevent recurrences; however, patients are advised to avoid nutrients which they do not tolerate. When patients have a clinical relapse systemic or topical corticosteroids are the treatment of choice. In moderately active disease and in patients who refuse to take corticosteroids high dose 5-aminosalicylic acid (at least 4 g/day) may be used alternatively. In patients with chronic complicated disease azathioprine is recommended.

Aminosalicylic Acids↗
PubMed1995

Treatment of active Crohn's ileocolitis with oral pH-modified budesonide. Germany Budesonide Study Group.

Budesonide is a topical steroid which after intestinal absorption is rapidly degraded into inactive metabolites in the liver. Its systemic bioavailability is only 10-15%. In the present open trial the efficiency and safety of oral pH-modified release budesonide were assessed in patients with active Crohn's ileocolitis. This report describes the results of the first 30 of 78 patients. After 6 weeks of treatment with 3 x 3 mg budesonide/day 67% of the patients were in clinical remission. Typical steroid-related side effects were observed in only one patient. Budesonide therefore seems to be suited as an alternative for classical steroids in patients with Crohn's ileocolitis. Its clinical efficacy is comparable with classical steroids but it's rate of steroid-related side effects is lower.

Administration, Oral↗
PubMed1994

Free radicals in inflammatory bowel diseases pathophysiology and therapeutic implications.

Inflammatory bowel diseases are characterized by the accumulation of granulocytes and monocytes/macrophages at the site of inflammation. Activation of these cells leads to the release of degradative enzymes, e.g., proteinases and glycosidases, and the production of reactive oxygen metabolites. This has been shown both in animal models of experimental intestinal injury, and in human inflammatory bowel disease. Scavenging of oxygen radicals protected tissue from damage in experimental inflammation models. Human studies with specific oxygen radical scavengers are rare, preliminary results appear promising. The fact that the aminosalicylates used in the treatment of inflammatory bowel disease are potent antioxidants underscores the important role of reactive oxygen metabolites in this setting.

Aminosalicylic Acids↗
PubMed1993

PMN-elastase in assessment of patients with inflammatory bowel disease.

PMN-elastase is a proteinase released by activated neutrophils. PMN-elastase was determined in two independent populations with inflammatory bowel disease. In an unselected population of 70 consecutive patients with Crohn's disease and 24 patients with ulcerative colitis with different degrees of disease activity plasma PMN-elastase levels were statistically significantly higher in patients with active than in patients with inactive disease [Crohn's disease: 80.5 +/- 33.2 ng/ml vs 60.1 +/- 24.6 ng/ml (mean +/- SD), P = 0.0017; ulcerative colitis: 98.2 +/- 54.9 ng/ml vs 59.2 +/- 16.8 ng/ml, P = 0.026]. PMN-elastase levels in feces were also higher in patients with active Crohn's disease (23.6 +/- 15.3 ng/g vs 13.6 +/- 12.5 ng/g, P = 0.0021) and active ulcerative colitis (46.5 +/- 60.5 ng/g vs 20.2 +/- 25.0 ng/g, P = 0.46), but the difference reached significance only in Crohn's disease. Correlation of disease activity and PMN-elastase in individual patients showed a statistically significant correlation between plasma and fecal elastase concentrations and disease activity in ulcerative colitis (plasma: r = 0.72, P < 0.001; feces: r = 0.57, P = 0.002). In patients with Crohn's disease only plasma levels of PMN-elastase (r = 0.423, P < 0.001) but not fecal elastase concentrations (r = 0.0083, P = 0.485) correlated significantly with disease activity. Plasma PMN-elastase correlated weakly with fecal PMN-elastase levels in Crohn's disease (r = 0.431, P < 0.01) and in ulcerative colitis (r = 0.515, P = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Inhibition of protein N-glycosylation by 2-deoxy-2-fluoro-D-galactose.

The effects of 2-deoxy-2-fluoro-D-galactose (dGalF) on N- and O-glycosylation of proteins was studied in rat hepatocyte primary cultures and in human monocytes. In hepatocytes, dGalF at concentrations of 1 mM or higher completely inhibited N-glycosylation of alpha 1-antitrypsin and alpha 1-acid glycoprotein, whereas 4 mM-2-deoxy-D-galactose (dGal) only slightly impaired N-glycosylation. In monocytes, 1 mM- or 4 mM-dGalF blocked N-glycosylation of alpha 1-antitrypsin and of interleukin-6, while O-glycosylation of interleukin-6 remained unaffected. In monocytes, dGal had no effect on protein N-glycosylation. Addition of uridine effectively prevented the UTP deficiency induced by dGalF, but had no effect on the inhibition of protein N-glycosylation by dGalF. Using 19F-n.m.r. spectroscopy, 2-deoxy-2-fluoro-D-galactose 1-phosphate (dGalF-1-P), UDP-dGalF and UDP-dGlcF could be identified as the major metabolites of dGalF in hepatocytes as well as in monocytes. In conclusion, compared with dGal, dGalF is a more efficient inhibitor of protein N-glycosylation. The effect is not caused by the depletion of UTP induced by dGalF, but rather by metabolites of dGalF. dGalF is metabolized not only in hepatocytes but also in peripheral blood monocytes, which can be used for ex vivo studies of disturbances in D-galactose metabolism.

Animals↗
PubMed1992

High concentrations of soluble tumor necrosis factor receptors in ascites.

Ascites and plasma concentrations of soluble tumor necrosis factor receptors p55 and p75 were measured in a prospective study in 34 patients (35 occasions of ascites) with hepatic (5 infected and 21 uninfected) and malignancy-related (9) ascites. All patients had high concentrations of both soluble tumor necrosis factor receptors in ascites and plasma; these were about 500 times higher than the corresponding tumor necrosis factor-alpha concentrations. Ascites levels of soluble tumor necrosis factor receptors p55 and soluble tumor necrosis factor receptors p75 were significantly elevated in patients with malignancy-related (p55: 26.0 +/- 8.6 ng/ml; p75: 20.5 +/- 17.4 ng/ml; mean +/- S.D.) and infected ascites (p55: 25.1 +/- 10.9 ng/ml, p75: 22.6 +/- 11.0 ng/ml) compared with patients with uncomplicated hepatic ascites (p55: 10.1 +/- 4.4 ng/ml; p75: 6.0 +/- 2.6 ng/ml). Patients with infected or malignancy-related ascites also showed higher soluble tumor necrosis factor receptor concentrations in plasma than did patients with plain hepatic ascites. Successful antibiotic treatment of peritonitis reduced soluble tumor necrosis factor receptor p55 and p75 ascites levels in three patients from 24.2 +/- 15.2 ng/ml to 10.7 +/- 1.9 ng/ml and from 20.2 +/- 14.4 ng/ml to 7.5 +/- 1.8 ng/ml, respectively. Soluble tumor necrosis factor receptors p55 and p75 at cutoff levels of 16.5 ng/ml and 9.5 ng/ml, respectively, differentiated between infected or malignant and plain hepatic ascites with diagnostic accuracies of 94% and 89%, respectively. They did not differentiate between infected and malignant ascites. The concentrations of soluble tumor necrosis factor receptor p55 were usually higher in ascites than in plasma in all subgroups of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Evidence for continuous stimulation of interleukin-6 production in Crohn's disease.

Increased serum concentrations of acute-phase proteins can be found in active inflammatory bowel disease. Because interleukin 6 (IL-6) is one of the main mediators of acute-phase protein synthesis by the liver, the serum concentrations of IL-6 and the acute-phase proteins C-reactive protein, alpha 1-antitrypsin, and alpha 1-acid glycoprotein were determined in 70 patients with Crohn's disease (CD) and 23 patients with ulcerative colitis (UC). Disease activities were determined by established clinical activity indices. Serum IL-6 concentrations were significantly (P less than 0.005) increased in patients with CD (mean +/- SEM, 6.8 +/- 0.9 U/mL) compared with patients with UC (mean, less than 4 U/mL) and healthy controls (mean, less than 4 U/mL). Of patients with CD, 68.5% had serum IL-6 concentrations of greater than or equal to 4 U/mL, compared with 21.7% of patients with UC and 0% of healthy controls. There was a tendency toward higher serum IL-6 concentrations in patients with active CD than in patients with inactive disease. However, these differences were not statistically significant. There was no correlation between IL-6 serum concentrations and clinical activity indices, possibly because of the short circulatory lifetime and rapid hepatic clearance of IL-6 from the portal venous blood. In contrast to serum IL-6, acute-phase proteins, which have a longer circulatory lifetime, were significantly correlated with clinical activity indices. Only the follow-up of individual patients with initially highly active disease showed a further increase in IL-6 levels during acute exacerbations of the inflammatory process. The results show that most patients with even moderately active CD have significantly increased serum concentrations of IL-6, most probably reflecting a continuous stimulation of IL-6-producing cells.

Acute Disease↗
PubMed1992

Evidence for the production of high amounts of interleukin-6 in the peritoneal cavity of patients with ascites.

The ascites and serum concentrations of interleukin-6 (IL-6) and interleukin-1 (IL-1) were determined in 21 patients with hepatic ascites and in 9 patients with malignancy-associated ascites. There was no evidence for bacterial peritonitis in any patients. All ascites samples contained high amounts of immunoreactive IL-6 [hepatic ascites 1730 +/- 2130 pg/ml (mean +/- SD), 1160 pg/ml (median); malignant ascites 4020 +/- 1510 pg/ml (mean), 3820 pg/ml (median)] but no IL-1. The mean ascites to serum ratios of IL-6 were 96 (median 49) in patients with hepatic ascites and 587 (median 480) in patients with malignant ascites. Ascites IL-6 was biologically active as determined by the B9 cell bioassay. The results indicate that even in the absence of infection IL-6 is produced in high amounts in the peritoneal cavity of patients with hepatic or malignant ascites.

Adult↗
PubMed1992

Human recombinant C5a enhances lipopolysaccharide-induced synthesis of interleukin-6 by human monocytes.

The effect of human recombinant C5a (hrC5a) on the synthesis of interleukin-6 (IL-6) was studied in human monocytes. Monocytes incubated in the absence of hrC5a and of bacterial lipopolysaccharide (LPS) produced only low amounts (less than 100 U/2 x 10(6) cells/16 h) of IL-6 activity. LPS in concentrations from 10 pg ml-1 to 10 ng ml-1 greatly stimulated the synthesis of IL-6 to about 50.000 U/10(6) cells/16 h. When hrC5a was added to the monocyte media maximal IL-6 synthesis was reached at lower LPS concentrations, i.e. at 0.1 ng ml-1 LPS in the presence of 100 ng ml-1 hrC5a. Maximal IL-6 production was not significantly enhanced by hrC5a. Metabolic labelling with [35S]-methionine followed by immunoprecipitation of IL-6 showed that the increased IL-6 activity in the medium of hrC5a treated monocytes was due to a stimulation of the de novo synthesis of IL-6. Increased amounts of IL-6 mRNA were found in monocytes treated with LPS and hrC5a compared with monocytes stimulated only with LPS. HrC5a prolonged the elevation of IL-6 mRNA levels after stimulation of monocytes with LPS. HrC5a thus enhanced the LPS-induced synthesis of IL-6 by human monocytes.

Cells, Cultured↗
PubMed1991

Inflammatory mediators in chronic inflammatory bowel diseases.

Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases (IBD) of unknown etiology. They are characterized by an activation of intestinal mononuclear cells. Cytokines play a crucial role in the regulation of the functions of these cells. An increased synthesis of the cytokines interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF alpha), which are primarily synthesized by activated monocytes/macrophages has been described in patients with IBD. The synthesis of interleukin-2 (IL-2) and of interferon gamma (IFN gamma), which are produced by lymphocytes, on the other hand, has been found to be decreased. The published data are, however, not quite consistent. In patients with IBD there is not only a stimulation of the local cytokine production in the gut. The blood levels and the synthesis of the cytokines IL-1, IL-6 and TNF alpha by peripheral blood mononuclear cells are also increased, in particular in patients with Crohn's disease. Drugs, which are commonly used for the treatment of IBD impair the synthesis of these cytokines in monocytes/macrophages.

Colitis, Ulcerative↗
PubMed1991

[Hepatology. New research results in its significance for the understanding of liver diseases].

By two exemplary clinical situations--acute viral hepatitis, acute-phase reaction of the liver--the significance of basic research for the understanding of clinical phenomena and for the development of new diagnostic and therapeutic procedures is demonstrated. The very different phenomena following infection with the hepatitis-B-virus can be explained by the variation in the interactions of virus and liver cell, by the immune reaction of the host, and by mutants of the virus. The reaction of the liver to an extrahepatic infection is mediated by interleukin-6, and characterized by an alteration in protein metabolism. The synthesis of acute-phase proteins is increased. The proteins confine the local injury and establish the homeostasis of the organism.

Acute-Phase Proteins↗
PubMed1991

Activation of monocytes during inflammatory bowel disease.

Inflammatory bowel diseases lead to a systemic acute-phase response. Monocyte activation plays a central role during systemic acute-phase response via secretion of inflammatory cytokines. We determined the activation of peripheral-blood monocytes in patients with inflammatory bowel diseases by measuring their interleukin-6 (IL-6) secretion. Blood was obtained from patients with active Crohn's disease before treatment [mean Crohn's disease activity index (CDAI) = 332 +/- 34] and from patients after treatment with prednisolone (mean CDAI index = 139 +/- 20). The mean serum IL-6 levels measured by a hybridoma growth assay (B9) were 23 +/- 4 U/ml before therapy and fell to 16 +/- 3 U/ml after treatment with prednisolone. Healthy persons and patients with inactive Crohn's disease usually had serum IL-6 levels below the detection limit of 4 U/ml. An ex vivo whole-blood system was used to measure IL-6 secretion by peripheral-blood monocytes with and without stimulation. Spontaneous IL-6 secretion in this system was about 9 U/ml in patients with Crohn's disease and below the detection limit of 4 U/ml in healthy controls. Moderate stimulation of blood cells [100 pg/ml lipopolysaccharide (LPS)] from patients with active Crohn's disease before and after treatment led to mean IL-6 concentrations of 1,160 +/- 514 and 131 +/- 54 U/ml, respectively. Maximal stimulation of peripheral blood before and after therapy by LPS (100 ng/ml) led to mean IL-6 concentrations of 5,570 +/- 1,660 and 6,220 +/- 1,630 U/ml, respectively. Thus, administration of glucocorticoids led to a rapid down-regulation of IL-6 synthesis by peripheral-blood monocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute-Phase Proteins↗
PubMed1991

Effects of cytokines on the liver.

Cytokines are essential for the communication not only between the liver and extrahepatic sites but also within the liver itself. Cytokines regulate the intermediary metabolism of amino acids, proteins, carbohydrates, lipids and minerals. Cytokines partially interact with classical hormones such as glucocorticoids, resulting in a complex network of mutual control. Since many cytokines exert growth factor-like activities in addition to their specific proinflammatory effects, the distinction between cytokines and growth factors is somewhat artificial. The liver is an important site of synthesis and the major clearance organ for several cytokines. In liver disease, cytokines are involved in the onset of intrahepatic immune responses (e.g., during viral hepatitis), in liver regeneration (e.g., after partial hepatectomy) and in the fibrotic and cirrhotic transformation of the liver such as chronic chemical injury or viral infection. Further studies of cytokine actions may lead to a better understanding of liver diseases and to the development of new immunomodulating therapeutic options.

Animals↗
PubMed1990

Hepatocyte specific long lasting inhibition of protein N-glycosylation by D-galactosamine.

The effect of D-galactosamine on protein N-glycosylation was studied in rat hepatocyte primary cultures for alpha 1-antitrypsin (three complex type oligosaccharide chains) and alpha 1-acid glycoprotein (six complex type oligosaccharide chains). D-Galactosamine at a concentration of 4 mM inhibited partially de novo N-glycosylation leading to the formation of alpha 1-antitrypsin lacking one to two and of alpha 1-acid glycoprotein lacking one to five of its carbohydrate side chains. In addition D-galactosamine interfered with oligosaccharide processing, leading to the formation of some carbohydrate side chains remaining in an endoglucosaminidase H sensitive, i.e., not completely processed, form. D-Galactosamine impaired the secretion of alpha 1-antitrypsin and of alpha 1-acid glycoprotein but did not inhibit the secretion of the unglycosylated albumin. The inhibitory effect of D-galactosamine on de novo glycosylation as well as on oligosaccharide processing lasted for at least 24 h after it had been removed from the cells. D-Galactosamine impaired the glycosylation of alpha 1-antitrypsin only in hepatocytes, but not in human monocytes. Furthermore, D-galactosamine did not impair the N- and O-glycosylation of interleukin-6 in human monocytes and in MRC 5 fibroblasts. The results indicate that the effect of D-galactosamine on protein glycosylation is restricted to D-galactosamine metabolizing hepatocytes and is not exerted by the drug itself but by its metabolites.

Acetylglucosaminidase↗
PubMed1990

Fate of interleukin-6 in the rat. Involvement of skin in its catabolism.

Iodinated recombinant human interleukin-6 (125I-rhIL-6) was intravenously injected into rats and its fate was studied during 24 h. Between 10-20 min after a single-dose injection, 125I-rhIL-6 accumulated in liver as previously reported [Castell et al. (1988) Eur. J. Biochem. 177, 357-361]. After 1 h, the radioactivity disappeared from the liver and accumulated in skin, reaching 35% of injected 125I-rhIL-6 5-8 h after injection. No comparable accumulation of radioactivity was found in skin when [125I]iodide or rat serum 125I-albumin was administered. Finally the radioactivity was detected as [125I]iodide in urine. Autoradiographic analysis of skin sections 5 h after 125I-rhIL-6 injection showed radioactivity in the interstitium. When the experiments were carried out with [35S]rhIL-6, essentially the same results were obtained: a decrease in radioactivity in the liver after 20 min, and a substantial increase in skin 7 h after injection. In vitro experiments showed that 125I-rhIL-6 is degraded by rat and human fibroblasts, whereas no degradation was observed with rat hepatoma cells (Fao) or human hepatocytes. These observations suggest the involvement of skin in the catabolism of IL-6.

Animals↗