首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 281 毫秒
1.
The expression of the 1 integrins was examined immunohistochemically in synoviocytes from normal synovial membrane and from chronic synovitis of different aetiology and intensity. Normal synoviocytes were 61-positive but lacked 1 through 5. In mild inflammation type A synoviocytes neo-expressed 1, 3, and 5 chains. In severe inflammation both type A and B synoviocytes expressed 3, 4, 5, and 6 chains. The effects of inflammatory cytokines, as single agents or in combination, on the 1 integrin expression in cultured normal synoviocytes was determined by immunocytochemistry and flow cytometry. The 1 chain, while absent in unstimulated synoviocytes, was induced by interleukin-1 (IL-1), tumour necrosis factor- (TNF-), and interferon- (INF-). This effect was enhanced by combining IL-1 and TNF-. Expression of the 3 chain was up-regulated by IL-1 and, more intensely, by IFN-. Transforming growth factor (TGF-) inhibited the up-regulating effect of IL-1 and antagonized the effect of IFN- on 3 chain expression. Expression of the 5 chain was up-regulated significantly by co-stimulation through IL-1 together with TGF- or TNF-. Thus, the 1 integrin profile of cytokine activated synoviocytes in vitro resembled that of synoviocytes in synovitis in situ. These data suggest that IL-1, TNF-, IFN-, and TGF- are likely to be among the effectors regulating 1 integrin expression in synoviocytes in vivo.  相似文献   

2.
TGF- plays a central role in the initiation and progression of pulmonary fibrosis. Glucocorticoids are frequently used to treat fibrotic diseases, but beneficial effects are often modest. Both TGF- and glucocorticoids have been reported to increase fibroblast contraction of native collagen gels, a model of fibrotic tissue remodeling. Therefore, we sought to determine how glucocorticoids interact with TGF- in this system. In this study, human fetal lung fibroblasts (HFL-1) were pretreated with or without TGF- for 72 h before they were cast into type I collagen gels. Various concentrations of glucocorticoids (budesonide or hydrocortisone) were added at the time of casting. Gel size was then monitored at different times after gel release. The surrounding media were collected for the assay of prostaglandin E2 (PGE2) and the cell lysates were analyzed for cyclooxygenase (COX) expression by immunoblot. Glucocorticoids alone significantly enhanced fibroblast-mediated contraction of collagen gels (P < 0.01) and dose-dependently inhibited PGE2 release by HFL-1 fibroblasts. TGF- significantly augmented gel contraction but also induced a 30% increase in PGE2 release and increased the expression of COX-1. Glucocorticoids inhibited TGF-1 induced-PGE2 release, and enhanced TGF- augmented gel contraction without significantly affecting TGF- augmented COX-1 expression. Indomethacin, a COX inhibitor, increased TGF- augmented gel contraction but had no further effect when added together with glucocorticoids. Thus, glucocorticoids can synergize with TGF- in augmenting fibroblast mediated collagen gel contraction through the inhibition of PGE2 production. Such interactions between glucocorticoids and TGF- may account, in part, for the lack of response of fibrotic diseases to glucocorticoids.  相似文献   

3.
Summary For the budding yeast Saccharomyces cerevisiae the mitotic cell cycle is coordinated with cell mass at the regulatory step start. The threshold amount of cell mass (reflected as a critical size) necessary for start is proportional to nutrient quality. This relationship leads to a transient accumulation of cells at start, termed nutrient modulation, upon enrichment of nutrient conditions. Nutrient enrichment abruptly increases the critical size needed for start, causing the smaller cells, produced in the previous cell cycle, to be delayed at start while growing larger. Here we show that, in S. cerevisiae, a second cell-cycle step, at mitosis, also exhibits nutrient modulation, and is, therefore, another point of cell-cycle regulation. At both mitosis and start, nutrient modulation was found through mutation to be regulated by the activity of the cyclin-related WHI1 (CLN3) gene product.  相似文献   

4.
Summary A small population of T cells does not express the conventional T cell receptor characterized by the and polypeptide chains (TCR) but instead, two polypeptides termed and (TCR). This alternative receptor is able to recognize antigen. It appears early in T cell ontogeny, but its role in the thymus prior to the availability of TCR remains unclear. In selected sites such as skin or gut TCR predominates in mice which might suggest a role of T cells in the first line of defense against infection, T cells secrete lymphokines and display cytotoxic activity. However, their activation requirements may differ from what is known for T cells since MHC-nonrestricted and also CD4 and CD8 negative T cells have been described. Preferential activation by mycobacterial antigens possibly indicates a special repertoire of the T cells. In various diseases slightly increased numbers of T cells were found, but these preliminary studies have not yet provided evidence for a major pathogenetic role of T cells.List of abbreviations C constant region (immunoglobulin or TCR gene segment) - CD4 cluster of differentiation 4 (mainly on helper cells) - CD8 cluster of differentiation 8 (mainly on cytotoxic cells) - D diversity region (immunoglobulin or TCR gene segment) - DNA desoxyribonucleic acid - IL2 interleukin 2 - J joining region (immunoglobulin or TCR gene segment) - kD kiloDalton - MHC major histocompatibility complex - NK natural killer (cells) - RA rheumatoid arthritis - TCR T cell receptor - V variable region (immunoglobulin or TCR gene segment)  相似文献   

5.
Summary The histology and immunohistology of twenty-seven malignant non-Hodgkin's lymphomas of the intestinal tract were studied. Nine of these cases were in the small intestine, ten in the ileocaecal region, two in the appendix and four in the large intestine. In one case, several locations in the gastrointestinal tract were involved. The so-called Kiel-Classification was applied. We have found thirteen lymphomas with low grade (lymphocytic, lymphoplasmacytic, centrocytic, centroblastic/centrocytic) and fourteen with high grade of malignancy (centroblastic, lymphoblastic, immunoblastic). For most of the lymphoplasmacytic and immunoblastic lymphomata a monoclonal pattern of intracellular immunoglobulin (IgM/kappa) was identified by the immunoperoxidase method. Tumour cells of lymphocytic, centrocytic, centroblastic/centrocytic, centroblastic and lymphoblastic lymphomas were always Ig-negative. The immunoperoxidase technique helped considerably in distinguishing between (monoclonal) malignant lymphomas and (polyclonal) lympho- or immunoproliferative processes.Six out of twenty-seven malignant lymphomas had developed from immuno-inflammatory diseases of the gut. Four of these were complications of coeliac disease. One had developed from a malabsorptive dermatitis herpetiformis Duhring, and one from a complication of a long-standing ulcerative colitis. In two patients with coeliac sprue and malabsorptive dermatitis herpetiformis Duhring respectively the ulcerating small intestinal lymphomas were initially misinterpreted as benigne ulcerative non-granulomatous jejunitis. The evidence from the literature summarized suggests strongly that the benign non-granulomatous jejunoileitis, lymphomatous ulcer, intestinal pseudolymphoma and malignant lymphoma, when associated with villous atrophy of adjacent mucosa and malabsorption symptoms, are all one condition, namely, malignant lymphoma.This study was supported by a grant from the Deutsche Forschungsgemeinschaft (Ot 53/4-6)  相似文献   

6.
Summary In 15 healthy, not specifically trained volunteers (age: 26.6±2.7 years) single equipotent doses of a selective 1-blocker with intrinsic sympathomimetic activity (ISA) (200 mg Epanolol-Visacor; V) and of a selective 1-blocker without ISA (100 mg Metoprolol; M) were compared with placebo (P) with respect to their influence upon physical performance capacity and metabolism in a random, double blind, cross-over experimental setting. The subjects underwent three step by step incremental treadmill tests and three treadmill endurance tests until volitional exhaustion. Maximum running speed and maximum oxygen uptake were used as measures of maximum performance capacity. Running speed and oxygen uptake related to individual anaerobic threshold, and running time and running distance in the endurance tests were used as measures of endurance capacity. Both maximum and endurance performances were reduced significantly by -blockade. No relevant differences were discerned between V and M. The uniform reduction in exercise heart rate with both -blockers demonstrated the application of equipotent doses. At rest, heart rate was significantly higher under V than under M. Carbohydrate metabolism was unaffected, both blockers showing equal inhibition of lipolysis during exercise. We conclude that intrinsic sympathomimetic activity has no influence upon physical performance and metabolism during selective 1-blockade.  相似文献   

7.
Summary The influence of transforming growth factor- (TGF-) on hematopoiesis has been evaluated by adding blocking antibodies against TGF- to colony forming assays (CFU-c). When optimum concentrations of recombinant growth factors, granulocyte-macrophage colony stimulating factor (GM-CSF), and interleukin-3 (IL-3) were added to stem cells from the peripheral blood of healthy individuals and certain patients with tumors or HIV infection, the anti-TGF- capable of blocking 5 ng/ml of active TGF- had no significant influence on erythroid or myeloid colony formation. However, in certain immunosuppressed individuals, anti-TGF- resulted in a significant decrease of erythroid colony formation and slight suppression of myeloid colony formation. The significant inhibition of hematopoiesis by plasma of HIV patients could be due to the presence of active forms of TGF-. The results of the blocking experiments are consistent with the concept that TGF- in low concentrations is essential for erythropoiesis and myelopoiesis but that higher levels of TGF- primarily inhibit erythropoiesis in vitro. TGF- serves as a coordinating factor when efficient recruitment of granulocytes and monocytes is more essential than erythropoiesis and stem cell growth.Abbreviations BFU-E burst forming unit-erythroid - CFC colony forming cells - CFU-GEMM colony forming unit-granulocyte/erythroid/macrophage/megacaryocyte - CFU-GM colony forming unit-granulocyte/macrophage - EPO erythropoietin - GM-CSF granulocyte/macrophage-colony stimulating factor - HIV human immunodeficiency virus - IL-1 interleukin-1 - IL-3 interleukin-3 - IMDM Iscove's Modified Dulbecco's medium - PBS phosphate buffered saline - TGF- transforming growth factor- - TNF- tumor necrosis factor-  相似文献   

8.
The effect of interferon- (IFN-) on the interaction between tumor cells and mesothelial cell layers was studied from the aspect of changes in mesothelial permeability. Mesothelial permeability was assessed as the percentage diffusion of radiolabeled albumin across the mesothelial cell sheets on Matrigel-coated filter cup assemblies. When lined gastric carcinoma cells (KATO-III) were seeded on the confluent mesothelial cell layers, the fine cobblestone appearance of the cell sheet was disrupted and mesothelial permeability significantly increased. The increase in permeability was suppressed by the addition of as little as 1 U/ml of IFN-. The effect of IFN- was observed when either the conditioned medium of tumor cells alone or the IFN--resistant tumor cells, K-562, was placed onto the mesothelium. The cobblestone appearance of the cell sheet was relatively well preserved in the presence of IFN-. In contrast, IFN- did not suppress tumor-induced mesothelial permeability. These results suggest that IFN- has the potential to protect the human mesothelial cell layers against tumor cells.  相似文献   

9.
Zusammenfassung Bei Nierenkranken, nicht renal Erkrankten, essentiellen Hypertonikern und gesunden Probanden wurde die Enzymaktivität der-Hexosaminidase und zum Vergleich der-Galaktosidase im 24 h-Urin bestimmt. Gegenüber allen anderen Gruppen wiesen Nierenkranke eine signifikant höhere Enzymaktivität der-Hexosaminidase bei jedem Patienten auf, während-Galaktosidase nur im Mittelwert erhöhte Werte zeigte. Die Ursache der Enzymerhöhung wird diskutiert.  相似文献   

10.
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGF- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFLF) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TGF-1, -2, or -3. Post-culture media were collected for ELISA assays of TGF-1, -2, and -3 . TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TFG-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and TGF-2 production and reduced expression of the up-regulated TGF-1 and TGF-2 mRNA induced by exogenous TGF-1, -2, or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   

11.
To determine the relative presence of TCR+ and TCR+ T cells in synovial tissue from patients with various types of inflammatory synovitis and in tissues from patients with a number of chronic T cell-mediated conditions, we stained frozen tissue sections with monoclonal antibodies in indirect immunofluorescence assays. In tissues obtained from patients with chronic T cell-mediated granulomatous conditions (Wegener's granulomatosis, lymphomatoid granulomatosis, granuloma annulare, Langerhan's cells granulomatosis, pigmented villonodular synovitis, Takayasu's arteritis, and talc granulomatosis), the T cells present were predominantly TCR+, without an increased presence of TCR+ cells. In contrast, 6 of 14 (43%) synovia from patients with rheumatoid arthritis (RA) showed increased TCR+ T cells (3–10 cells/hpf). The RA synovia with increased TCR+ cells present had an increased tissue inflammation score compared to RA synovia with few TCR+ cells [18.6±5.8 versus 11.6±4.2 (mean±SE),P<0.05]. In contrast, synovia from patients with osteoarthritis, systemic lupus erythematosus, and trauma did not show an increased presence of TCR+ T cells. Thus, in cellular inflammatory infiltrates the presence of increased TCR cells is not a component of noninfectious granulomatous inflammation but is found in approximately 40% of RA synovia with high levels of inflammation.  相似文献   

12.
In the present study, we compared the nicotin-amide adenine dinucleotide (NAD) reducing potencies of flow anoxia and non flow anoxia in the cat brain cortex. In animals anaesthetized with alpha-D-glucochloralose flow anoxia and non flow anoxia were produced by ventilating for 2 and 25 min, respectively, with nitrogen gas. Following non flow anoxia, the brain cortices of dead animals were superfused with oxygen saturated artificial cerebrospinal fluid (mock CSF), and subsequently with CSF containing various concentrations (10–3–10–1 M) of potassium cyanide. NADH (reduced NAD) fluorescence of the brain cortex was measured through a cranial window with microscope fluororeflectometer. Ventilating the animals for 2 and 25 min with nitrogen gas increased cortical NADH fluorescence (NAD reduction) by 43.5±2.8% and 135.3±6.1%, respectively. Oxygen saturated CSF superfusion of the ischemic brain cortex restored the cortical NAD/NADH redox state to the preanocic level (oxidation of NADH). 10–1 M cyanide, applied after superfusion of the brain cortex with oxygen saturated CSF resulted in comparable NAD reduction to that produced by non flow anoxia. On the basis of these findings it is suggested that non flow anoxia leads to much greater cortical NAD reduction than flow anoxia, because oxygen tension in the cortex may not fall to zero mm Hg during nitrogen anoxia lasting for 2 min. Besides this, a more pronounced substrate mobilization and acidosis may also contribute to the greater NAD reducing potency of non flow anoxia. Finally, since 10–15 min after the death of the animal the cerebral carbohydrate reserves are completely exhausted, and in our experiments non flow anoxia, reoxygenation of the ischemic brain cortex and inhibition of the cortical mitochondrial electron transport by cyanide (10–1 M) resulted in comparable redox state changes (as far as their magnitude is concerned), it is concluded that the recorded changes in NADH fluorescence were of mitochondrial origin.  相似文献   

13.
Cardiac sodium channels (Nav1.5) comprise a pore-forming -subunit and auxiliary -subunits that modulate channel function. In the heart, 1 is expressed throughout the atria and ventricles, whilst 3 is present only in the ventricles and Purkinje fibers. In view of this expression pattern, we determined the effects of 3 and 1 co-expression alone, and in combination, on Nav1.5 stably expressed in Chinese hamster ovary cells. The current/voltage relationship was shifted –5 mV with either 1 or 3 co-expression alone and –10 mV with co-expression of both 1 and 3. In addition, 3 and 1/3 co-expression accelerated macroscopic current decay. There were significant hyperpolarizing shifts in equilibrium gating relationships with co-expression of 1 and 3 alone and in combination. Co-expression of 1/3 together resulted in a greater hyperpolarizing shift in channel availability, and an increase in the slopes of equilibrium gating relationships. Co-expression of 3 and 1/3, but not 1, slowed recovery from inactivation at –90 mV. Development of inactivation at –70 and –50 mV was accelerated by -subunit co-expression alone and in combination. -Subunit co-expression also reduced the late Na current measured at 200 ms. In conclusion, -subunits modulate Nav1.5 gating with important differences between co-expression of 1 and 3 alone and 1/3 together.  相似文献   

14.
Experimental data on distant intercellular electromagnetic interaction between two tissue cultures when one of them is exposed to factors of biological (viruses) or chemical (mercuric chloride) nature are presented; the characteristic response of the intact culture is in the form of a mirror cytopathic effect.Laboratory of Biophysics, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 337–339, March, 1980.  相似文献   

15.
According to the amyloid cascade hypothesis, sporadic Alzheimers disease (AD) is caused by the production and aggregation of -amyloid (A), and the production of A has recently been linked to the metabolism of cholesterol. We have previously published clinical studies where the effect of statin treatment on A production has been investigated. No effect on A was found, which is in disagreement with cell and animal studies. In the present study we investigated the effect of statin treatment on a disease-specific pattern consisting of a C-terminally-truncated quintet of A peptides. Nineteen patients with AD were treated with simvastatin for 12 months and the quintet of A peptides were analysed in cerebrospinal fluid before and after treatment. Also included was a group of 15 untreated patients with AD. We found that the A peptide pattern at baseline was in agreement with earlier findings; however, we did not find any change in the A peptide pattern after statin treatment. We suggest that clinical studies with extended treatment periods are performed where higher dosages of statins are used. We also believe that the pleiotropic effects of statins should be investigated further in order to elucidate the connection between Alzheimers disease and statin treatment.  相似文献   

16.
Zusammenfassung Es wird ein Überblick über die molekularen Aspekte der Katecholaminwirkung und ihre klinischen Konsequenzen gegeben. Sowohl - als auch (in einigen Geweben) -Rezeptoren sind an das membrangebundene Adenylat-Cyclase System gekoppelt.Die adrenergen Rezeptoren sind separate Membranbestandteile. Ihre Anzahl und die Relation zwischen - und -Rezeptoren sind ständigen Änderungen unterworfen. Die Umwandlungsvorgänge auf Rezeptorebene werden gesteuerteinmal durch die Konzentration adrenerger Agonisten im Blut,zum anderen durch diätetische und endokrine Einflüsse.Erste klinische Untersuchungen weisen daraufhin, daß bei Langzeittherapie mit 2-adrenergen Agonisten mit einer Desensibilisierung der Zielorgane auf Rezeptorebene zu rechnen ist.  相似文献   

17.
The cytokines, interferon- (IFN-), tumor necrosis factor- (TNF-rpar;, and interleukin-2 (IL-2) are important endogenous proinflammatory proteins and have been linked to disease activity in multiple sclerosis. In this study, we use flow cytometric methodology to compare the secretion of IFN-, IL-2, and TNF- from peripheral blood-derived T cells of multiple sclerosis patients to the secretion in healthy controls. The percentages of IFN-, IL-2, and TNF- secreting cells are not significantly different between multiple sclerosis patients and controls. However, the TNF- secreting CDS cell percentage is correlated with the IFN- and IL-2 secreting CD3 cell percentages in multiple sclerosis patients. In the controls, only the TNF- secreting CD3 cell percentage is correlated with IFN-. These findings show that correlated secretion of cytokines occurs in multiple sclerosis and suggest that concerted intercytokine interactions may play an important role in the disease.  相似文献   

18.
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   

19.
Blood stroke volume in rats aging 21 and 56 days decreased during -adrenoceptor blockade with propranolol, but increased again by the 15th minute after treatment. Suprathreshold stimulation of the stellate ganglion decreased the stroke volume and increased the heart rate in control animals. Electrical stimulation after -adrenoceptor blockade was followed by a further decrease in stroke volume in young rats. In 100-day-old animals this parameter remained unchanged, while the cardiac output improved.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 10, pp. 393–396, October, 2004  相似文献   

20.
Summary Primary cilia were present in the endothelial cells of human aortic fatty dots and streaks but not in those of normal intima. They had the features of cilia of the 9+0 axonemal configuration observed in many other cells. A lateral foot process and transitional fibers anchored the ciliary basal body in the cytoplasm, but rootlets were not identified in material examined. Ladder-like configurations interconnected the two centrioles (=diplosome) of control endothelium.The primary cilia of endothelium differed from those of the rudimentary type observed in smooth muscle cells in similar lesions of man, but shared many features with cilia of those present in experimental atherosclerosis in rabbit.Cilia were rarely described in vascular endothelium. It is believed that, to date, they were not reported to occur in normal or pathological arteries in man.It is being stressed that whereas the significance of these unusual organelles remains uncertain, their widespread occurrence may indicate that their role is more important than was believed previously, and they should cease being a curiosity only.Presented-in-part at the Workshop of the American Heart Association: Evolution of the Human Atherosclerotic Plaque, Rockville, Maryland, September 20–23, 1986.Dedicated to Professor Dr. Gotthard Schettler, Department of Internal Medicine, University of Heidelberg, FRG, on the occasion of his 60 birthday (April, 1987).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号