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1.
Recovery from hemorrhagic shock (HS) is frequently accompanied by bowel stasis. The aim of this study was to examine whether or not HS initiates an inflammatory response that includes production of cytokines, specifically G-CSF and interleukin-6 (IL-6), and recruitment of leukocytes within the intestinal muscularis which contribute to impaired muscle contractility. Sprague-Dawley rats were subjected to HS (MAP 40 mm Hg for 156 min) followed by resuscitation, and then they were killed at 4 hr. Shock animals demonstrated accumulation of PMNs in the jejunal muscularis and decreased spontaneous and bethanechol-stimulated muscle contractility. Semiquantitative RT-PCR demonstrated elevated levels of IL-6 and G-CSF mRNA in shock animals in full-thickness jejunum and in mucosa and muscularis layers compared to sham controls. Immunostaining demonstrated increased IL-6 protein production within the muscularis externa and submucosa. In situ hybridization studies localized G-CSF mRNA production to the submucosa. Gel shift assays revealed increased NF-B and Stat3 activity in full-thickness jejunum and jejunal layers of shock animals. Activation of Stat3 also was demonstrated in normal muscularis tissue exposed to IL-6 and G-CSF in vitro. IL-6 and G-CSF are produced in the muscularis and mucosa layers of the gut in HS where they may contribute to PMN recruitment and smooth muscle dysfunction.  相似文献   

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Phorbol esters induce inflammation in rodents by activating protein kinase C. We determined whether nuclear factor-B (NF-B) and tumor necrosis factor- (TNF-) play role in the formation of gastric ulcer induced by phorbol-12-myristate-13-acetate (PMA) in rats. Subserosally injected PMA dose-dependently induced gastric mucosal ulcer. Activation of NF-B in the gastric mucosa corresponding to the PMA injection sites was observed before the ulcers became obvious as assessed by an in situ fluorescence DNA binding assay and electrophoretic mobility shift assay. The NF-B activation and subsequent ulcer formation were significantly inhibited by injection of pyrrolidine dithiocarbamate, proteasome inhibitor (MG132), or NF-B decoy. Antibody against TNF- significantly inhibited ulcer formation without attenuating NF-B activation. These results suggest that both NF-B activation followed by TNF- release contribute to tissue damage in PMA-induced gastric ulcer formation.  相似文献   

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Adhesions of leukocytes to hepatocytes andsinusoidal endothelial cells mediates the induction andprogression of hepatic injury. However, in contrast toendothelial cells, information regarding the regulation of interactions between leukocytes andhepatocytes is limited. In the present study, weinvestigated the effect of inflammatory mediatorsincluding lipopolysaccharide (LPS), staphylococcalenterotoxin B (SEB), interferon- (IFN-), tumornecrosis factor- (TNF-), andinterleukin-1 (IL-1) on the adhesion ofpolymorphonuclear leukocytes or lymphocytes to primarycultured rat hepatocytes, and on the expression of intercellular adhesionmolecule-1 (ICAM-1) gene in hepatocytes. Bothpolymorphonuclear leukocyte and lymphocyte adhesion tohepatocytes were enhanced after exposure of hepatocytes to IFN- and TNF-, but not afterexposure to LPS, SEB or IL-1. The adhesion inducedby either IFN- or TNF- was inhibited bymonoclonal antibodies against ICAM-1 or lymphocytefunction-associated antigen-1 (LFA-1). Nonstimulated hepatocytesexpressed faintly ICAM-1 mRNA, which increased slightlyduring the culture period. ICAM-1 mRNA expression wasup-regulated to a greater extent by incubating hepatocytes with IFN- or TNF-,and peaked after 12 hr of incubation with TNF-and after 24 hr with IFN-. These results indicatethat IFN- and TNF- induce the expressionof ICAM-1 on parenchymal hepatocytes and that theLFA-1-ICAM-1 pathway plays an important role in theinteraction between hepatocytes and neutrophils orlymphocytes.  相似文献   

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Purpose To investigate the association between Helicobacter pylori infection and its inflammatory reaction in gastritis, gastric ulcer, and gastric cancer, a new tumor necrosis factor- (TNF-)-inducing protein of H. pylori was studied.Methods The HP0596 gene of H. pylori was identified as the TNF--inducing protein (Tip) gene from genome sequence of H. pylori strain 26695. Using recombinant Tip (rTip) and deleted Tip (rdel-Tip) proteins, the latter of which lacks six amino acids containing two cysteines in the N-terminal domain, we examined their activities in TNF- gene expression and NF-B activation in both Bhas 42 (v-H-ras transfected BALB/3T3) cells and mouse gastric epithelial cell line MGT-40, and in vitro transformation of Bhas 42 cells.Results Tip protein as a homodimer form (38 kDa) was found in both extracts and culture medium of various H. pylori strains. rTip significantly induced TNF- gene expression and NF-B activation in both Bhas 42 cells and MGT-40, and induced in vitro transformation of Bhas 42 cells. However, rdel-Tip did not. Treatment with MG-132, a proteasome inhibitor, inhibited translocation of NF-B p65, and abrogated TNF- induction induced by Tip protein.Conclusion Tip is a new carcinogenic factor released from H. pylori mediated through NF-B activation.  相似文献   

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Summary This study was designed to investigate acute effects of various doses of the cytokines IFN-alpha, IFN-gamma Interleukin 2 and tumor necrosis factor alpha on white blood cell differential counts. Before initiation of phase II trials, a dose-determination phase was performed, where three different dose levels of each cytokine were applied as a single dose. White blood cell differential counts were assessed immediately before and 2, 12, 24, 48 and 168 h after injection. Patients enrolled suffered from metastatic cancer or chronic active hepatitis. In addition, IFN-alpha was administered to five healthy volunteers. Results indicate that cytokines cause rapid and transient changes in the numbers of leukocyte subsets. Hematologic changes were cell-type- and cytokine-specific: transient lymphopenia was observed after administration of all four cytokines, reaching a nadir 12 to 24 h after subcutaneous injection. Administration of TNF-alpha and IFN-gamma also caused transient monocytopenia. Neutrophilia developed after administration of Interleukin 2, IFN-alpha and TNF-alpha. We conclude that cytokines play a key role in the regulation of peripheral blood cell traffic by their capacity to influence homing patterns of peripheral blood leukocytes.  相似文献   

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We recently reported that hyperthermia induces pancreatic expression of heat shock proteins (HSPs), particularly HSP70 isoforms, and protects against cerulein pancreatitis. We have now studied whether a double hyperthermia amplifies these effects and whether hyperthermia also protects against dibutyltin dichloride (DBTC)-induced pancreatitis. A further aim was to examine whether hyperthermia induces changes in transforming growth factor-1 (TGF-1). Following pretreatment without or with a single or double hyperthermia, pancreatitis was induced by application of cerulein or DBTC. Pancreatic HSP and TGF-1 expression were studied by immunoblotting. Pancreas injury was assessed by light microscopy and serum pancreatic enzyme activity. Hyperthermia as well as DBTC induced HSP72, whereas cerulein did not. A double hyperthermia led to a further increase in HSP72 compared to a single heat stress. In both models, hyperthermia significantly reduced pancreatic injury. Although a double hyperthermia slightly decreased the severity of cerulein pancreatitis compared to a single heat treatment, an improved pancreas protection against DBTC cytotoxicity was not achieved. We also found that hyperthermia induces the expression of TGF-1. In conclusion, hyperthermia preconditioning exerts protective effects against two pathophysiologically different types of pancreatitis by a mechanism that involves the up-regulation of HSP70 isoforms as well as TGF-1.  相似文献   

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Background. Recently, therapeutics employing knowledge on various signaling pathways are being developed, with NF-B being one of the most promising targets. NF-B has been suggested to play a role not only in the induction of inflammatory mediators, but also in the protection from cell death. Objectives. This study pursued the role of the NF-B pathway in the regulation of chondrocyte death induced by tumor necrosis factor alpha (TNF-) and of the pertinent target molecules involved. Methods. The human chondrocyte cell line C28/I2 was used for the experiment. Chondrocytes were transduced with adenovirus-encoding IkappaB (IB) superrepressor which inhibits NF-B activation, and treated with TNF-. The proportion of cell death was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazdium bromide (MTT) assay. Activation of p38 mitogen activated protein (MAP) kinase and phosphatidylinositol 3-kinase (PI3K) by TNF- was inhibited with SB202190 and Ly 294002 respectively. The expression of apoptosis related protein was analyzed with western blot assay, and the activation of c-Jun N-terminal kinase (JNK) by solid-phase kinase assay. Results. Treatment with TNF- led to cell death in 23% and 50% of ad-IB-SR infected chondrocytes after 24 and 72 h respectively. The expression of Bcl-XL, Bcl-2, and XIAP significantly decreased, and activation of JNK was prolonged for up to 6 h in infected cells treated with TNF-. Preincubation with p38 inhibitor or PI3K inhibitor before TNF- led to a significant increase in cell death in ad-IB-SR transduced chondrocytes, resulting in 53% and 30% cell death after 24 h for p38 inhibitor and PI3K inhibitor respectively. Conclusion. In our experimental system, specific inhibition of NF-B activation rendered chondrocytes susceptible to cell death induced by TNF-. The cell death was enhanced by inhibition of another signaling pathway such as p38 MAP kinase or PI3K. The expression of Bcl-XL, Bcl-2 and XIAP and activation of JNK were affected by ad-IB-SR transduction, implying a role in the NF-B regulated cell survival signaling in human chondrocytes.  相似文献   

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The exact immunological mechanisms underlyingalcoholic chronic pancreatitis are unclear. Toinvestigate the role of the tumor necrosis factor (TNF)receptor pathway the serum levels of TNF-,soluble TNF receptors-p55/-p75, and CRP were determinedby ELISA in 34 patients with late-stage alcoholicchronic pancreatitis and 28 controls. The diseaseactivity (Balthazar scoring system) of acutepancreatitis on the background of late-stage chronicpancreatitis correlated with an increase of functionallyactive TNF receptor-p55/-p75 serum levels. Unstimulatedperipheral blood mononuclear cells are one source of soluble TNF receptors and demonstrated asystemic leukocyte activation. The marked enhancement ofsoluble TNF receptors suggests that alcoholic chronicpancreatitis may be characterized by transient peaks of in situ TNF- productionpreceding a long-lasting release of soluble TNFreceptors. The data demonstrate immunological changescharacteristic of acute pancreatitis in late-stagealcoholic chronic pancreatitis.  相似文献   

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Summary The fate of the weak base N-nitrosonornicotine (2-14C-labeled) has been studied in mice. Whole-body autoradiography showed that the radioactivity was rapidly distributed throughout the body, which probably reflects an ability of the non-protonated compound to freely pass biological membranes and distribute evenly in the intra- and extracellular tissue water. Metabolites which were firmly bound to tissue macromolecules — retained throughout the observational period (24 h) — were present in the tracheobronchial and nasal mucosa, the liver, the submaxillary and sublingual salivary glands and the esophagus. Radioactivity in the lacrimal gland, the gastrointestinal contents, the urinary bladder, and the gallbladder seems to be related to excretion of the substance and/or its metabolites. A binding to the melanin in the eye and hair was observed in vivo and in vitro. Experiments with mice pretreated with diethyldithiocarbamate and nialamide showed that these substances partially inhibited the metabolism of N-/14C/nitrosonornicotine. CO2 was not recovered in the breath during the 4 h following the administration of N-/14C/nitrosonornicotine.Sponsored by the Swedish Tobacco Company (Grant No. 7820)  相似文献   

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In addition to regulating blood pressure and body fluid homeostasis, the renin-angiotensin system (RAS) is also involved in hepatic fibrogenesis. We aimed to investigate the effect of losartan, an angiotensin II (Ang II) antagonist, on CCl4-induced hepatic fibrosis in rats. Hepatic fibrosis was induced by a subcutaneous injection with 50% CCl4 in Sprague-Dawley rats. The amount of CCl4 administered was 1 mg/kg. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in plasma and hydroxyproline (Hyp) contents in liver tissue were assayed by spectrophotometry. Hyaluronic acid (HA) and procollagen III (PC III) were assessed by radioimmunoassay. Tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) levels in culture supernatants of Kupffer cells (KCs) stimulated with Ang II was determined by ELISA. Liver samples collected after 12 weeks of CCl4 treatment were stained with hematoxylin and eosin, then scored. Losartan (2.5, 5, and 10 mg x kg(-1), ig) and captopril (100 mg x kg(-1), ig) significantly decreased liver and spleen indexes, serum transaminase (AST, ALT) activities, HA and PC III levels, and Hyp contents in liver tissue in rats of hepatic fibrosis. Histopathological scores showed that losartan had an inhibitory effect on the progression of hepatic fibrosis. In in vitro experiments, losartan (1 x 10(-9) - 1 x 10(-5) M) significantly reduced TNF-alpha and TGF-beta1 levels in culture supernatants of KCs, but captopril (1 x 10(-5) M) did not. The results showed that losartan significantly inhibited the progression of hepatic fibrosis induced by CCl4, and the inhibitory effect of losartan on hepatic fibrosis might be associated with its ability to inhibit the production of TNF-alpha and TGF-beta1 by activated KCs.  相似文献   

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Summary One of the mediators responsible for the induction of the production of acute phase proteins by hepatocytes is interleukin-6 (IL-6), formally known as hybridoma growth factor (HGF). In a prospective study the biological significance of IL-6, but also the relationship with the acute phase response (C-reactive protein [CRP], 1-antitrypsin and 1-acid glycoprotein) during flare-ups in 12 systemic lupus erythematosus (SLE) patients was investigated. Only 2 SLE patients showed sustained elevated IL-6 levels, and in one of these patients a clear correlation was found between the increases in IL-6 and the acute phase response. In the other SLE patients hardly any response or change in the levels of IL-6, CRP, and/or 1-antitrypsin was found. In contrast to the profiles of 1-acid glycoprotein, in seven of the SLE patients a significant increase in the serum levels took place in the period preceding the exacerbation. This difference between the three acute phase proteins suggests that the regulatory mechanisms are different. Our results are in agreement with the findings that IL-6 might be responsible for the CRP response.  相似文献   

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The aim of the study was to investigate the effect of the immunosuppressant FK 506 (tacrolimus hydrate) on acute liver injury induced by Propionibacterium acnes and lipopolysaccharide (LPS). Acute liver injury was induced in male Wistar rats by injecting the animals with P. acnes (10 mg/rat), and administering LPS (10 g/rat) seven days later. One group was given FK 506 (1 mg/kg) 24 and 2 hr before administration of LPS, and the other group was given the same dose of saline. The 24-hr survival rate, serum alanine aminotransferase (ALT) concentration, and tumor necrosis factor (TNF) - mRNA and protein concentrations in the liver and spleen were then compared. Hepatic macrophages were also isolated from rats seven days after P. acnes injection, LPS, and FK 506 or saline were added to the culture supernatant, and TNF- production was studied. The 24-hr survival rate was 100% in the FK 506-treated group, in contrast with 16.6% in the saline group. Four hours after LPS injection, the serum ALT concentration was 755 ± 401 in the saline group versus 119 ± 42 units/ml (P < 0.01) in the FK 506-treated group. The serum TNF- concentration was lower in the FK 506-treated group (1419 ± 957 pg/ml) than in the saline group (9205 ± 2215) (P < 0.01). The mRNA and protein concentrations in the liver and spleen in the two groups did not differ significantly 1 hr after LPS injection but were significantly lower in the FK 506-treated group after 4 hr. FK 506 did not directly inhibit TNF- production by isolated cultured hepatic macrophages. FK 506 is unable to inhibit initial TNF- production by hepatic macrophages (or probably that by splenic macrophages either) stimulated by injection of LPS in P. acnes + LPS-induced acute liver injury. However, the immunosuppressant does limit hepatic damage by inhibiting subsequent aggravation of inflammation by the cytokine network.  相似文献   

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The T-lymphoproliferative syndrome is characterized by a proliferation of large granular lymphocytes (LGL). It is often associated with neutropenia, and in 30% of cases with rheumatoid arthritis (RA). Phenotypic analysis has demonstrated that in most cases of RA with T-proliferative disease, the LGL represent T cells with a clonal rearrangement of the / T cell receptor (TCR2). Here, three patients with / TCR1+ LGL proliferation suffering from long-standing arthritis and neutropenia are described. The first patient with RA showed an expansion of a heterogeneous CD2+ CD16+ CD56- LGL population, of which 30% coexpressed TCR1 with V1 rearrangement. The second patient with ankylosing spondylitis and RA was suffering from proliferation of TCR1+ (V9-, V1-), CD2+ CD16- CD56- LGL with low coexpression of CD8. The third patient with RA was suffering from a proliferation of TCR1+ (V1+, V9-) CD4- CE8- CD16- CD56- lymphocytes. On the basis of these unusual findings, the pathogenetic role of TCR1+ T cells in RA is discussed.  相似文献   

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Aims/hypothesis The coactivator of nuclear receptors, peroxisome proliferator-activated receptor- coactivator-1 (PGC-1) has been implicated in a series of events that contribute to the control of glucose metabolism. We have recently reported the use of a PGC-1 antisense oligonucleotide (PGC-1AS) that inhibits up to 60% of PGC-1 expression in pancreatic islets, leading to increased insulin secretion. This oligonucleotide was used in this study to try to ameliorate diet-induced type 2 diabetes in a genetically predisposed mouse strain (Swiss mice).Materials and methods Glucose and insulin tolerance tests, euglycaemic–hyperinsulinaemic clamp, immunoprecipitation assays, immunoblotting assays and immunohistochemistry were used in this investigation.Results Swiss mice became obese and overtly diabetic after 8 weeks of feeding with chow containing 24% saturated fat. One daily dose (1.0 nmol) of PGC-1AS significantly reduced glucose and increased insulin blood levels without affecting food intake and body weight. These effects were accompanied by a reduced area under the glucose curve during an intraperitoneal glucose tolerance test, an increased constant of glucose decay (Kitt) during an insulin tolerance test, and an increased glucose consumption rate during a euglycaemic–hyperinsulinaemic clamp. Moreover, mice treated with PGC-1AS presented an outstanding reduction of macroscopic and microscopic features of hepatic steatosis. These effects were accompanied by reduced expression or function of a series of proteins involved in lipogenesis.Conclusions/interpretation PGC-1 is an attractive target for pharmacological therapeutics in type 2 diabetes mellitus and diet-induced hepatic steatosis.  相似文献   

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Summary Leukemic cells of a 20 year old patient, suffering from acute lymphoblastic leukemia, were characterized by surface marker and functional analysis. A significant cell population within this type of leukemia expresses concomitantly the CD4 and CD8 antigen on the same cell and might represent a new differentiation stage of T-cells with the / receptor. The leukemic cells show a distinct pattern of growth response to mitogens and lymphokines, which might correlate to their differentiation stage. Moreover, a natural killer-like activity can be induced in these cells by IL-2.Abbreviations FITC fluorescein isothiocyanate - PE phycoerythrin - IL-2 interleukin 2; - / TCR gamma/delta T cell receptor - NK natural killer - PBL peripheral blood lymphocytes - T-ALL acute T lymphoblastic leukemia - ConA concanavalin A - PMA phorbol myristate acetate - BM bone marrow - IL-2R IL-2 receptor - TdT terminal deoxynucleotidyl transferase Supported by the Deutsche Forschungsgemeinschaft (DFG Wi-728/3-1)  相似文献   

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Nathens  Avery B. 《Sepsis》1999,3(1):57-64
Both acute pancreatitis and severe trauma induce a systemic sterile inflammatory process which leads to a high incidence of remote organ dysfunction and death. Several attributes of these two entities make them ideal for evaluation of the effects of mediator-directed therapy. The rationale and evidence for mediator-directed therapy in pancreatitis and trauma are reviewed. In pancreatitis, organ dysfunction and death are best prevented using strategies designed to limit the inflammatory response, particularly IL-1a and IL-10. By contrast, the sequelae of a post-traumatic systemic inflammatory response are best mitigated using strategies designed to limit neutrophil adhesion.  相似文献   

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