Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042384 (vasculitis)
 20,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Wegener's granulomatosis is an organ- and/or life-threatening autoimmune disease of as yet unknown etiology. The classic clinical triad consists of necrotizing granulomatous inflammation of the upper and/or lower respiratory tract, necrotizing glomerulonephritis, and an autoimmune necrotizing systemic vasculitis affecting predominantly small vessels. The detection of antineutrophil cytoplasmic antibodies directed against proteinase 3 (PR3-ANCA) is highly specific for Wegener's granulomatosis. ANCA positivity is found only in about 50% of the patients with localized Wegener's granulomatosis (which is restricted to the respiratory tract and affects < or = 5% of the patients), whereas PR3-ANCA positivity is seen in 95% of the patients with generalized Wegener's granulomatosis. Studies showing an expansion of circulating tumor necrosis factor-(TNF-)alpha-producing Th1-type CD4(+)CD28(-) T-cell effector memory T-cells and their presence as Th1-type cytokine profile- driving cell population within granulomatous lesions provide the rationale for using TNF-alpha-blocking agents in Wegener's granulomatosis refractory to standard induction therapy with cyclophosphamide and corticosteroids ("Fauci's scheme"). Vasculitis is an independent risk factor for diffuse endothelial dysfunction and may be a consequence of TNF-alpha action on endothelial cells. Recently, another study has shown intima-media thickening of the wall of the common carotid artery and bulb, as well as a significantly increased incidence of stroke, myocardial infarction and occlusive artery disease in Wegener's granulomatosis. This study suggests that systemic inflammation and vasculitis contribute to accelerated arteriosclerosis in Wegener's granulomatosis.
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PMID:Wegener's granulomatosis. 1496 41

Antineutrophil cytoplasm antibodies (ANCA) activate TNF-alpha-primed neutrophils to undergo a respiratory burst. The intracellular signals that mediate activation have not been studied extensively but could increase the understanding of the pathogenesis small vessel vasculitis. It was demonstrated that ANCA-IgG induced phosphorylation of the tyrosine kinase Syk in TNF-alpha-primed neutrophils from healthy donors. Syk was not phosphorylated in response to ANCA F(ab')(2). Furthermore, Syk phosphorylation was attenuated by blockade of both low-affinity Fcgamma receptors and CD18. Similarly, low-affinity Fcgamma receptor blockade reduced ANCA-induced superoxide production. In patient-derived neutrophils, the high-affinity Fcgamma receptor FcgammaRI was also demonstrated to be involved in ANCA-induced superoxide production. However, Syk phosphorylation was not attenuated by blockade of the FcgammaRI, present on neutrophils from vasculitis patients. The tyrosine kinase inhibitor 4-Amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine inhibited the ANCA-induced respiratory burst and Syk phosphorylation, suggesting that Src kinases lie upstream of Syk activation but downstream of ANCA engagement of Fcgamma receptors. Piceatannol, another tyrosine kinase inhibitor, also inhibited ANCA-induced Syk phosphorylation and the ANCA-stimulated respiratory burst, supporting the proposed functional role for Syk in ANCA signaling. ANCA-induced phosphorylation of Cbl and intracellular calcium transients, potential downstream mediators of Syk activation, were also blocked by tyrosine kinase inhibitors. While it has previously been shown that pertussis toxin diminishes the ANCA-induced respiratory burst, indicating heterotrimeric G protein involvement, Syk phosphorylation and calcium transients were unaffected by pertussis toxin. Collectively, these data show that Syk phosphorylation is induced during ANCA-triggered neutrophil activation.
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PMID:Activation of Syk in neutrophils by antineutrophil cytoplasm antibodies occurs via Fcgamma receptors and CD18. 1497 83

The gold standard for inducing remission in systemic necrotizing vasculitis (SNV) and severe lupus nephritis is (and remains) the combination of cyclophosphamide and glucocorticoids. Long-term treatment with cyclophosphamide is limited because of toxicity. Recent prospective studies in antineutrophil cytoplasmic antibody (ANCA)-associated SNV revealed that after achievement of clinical remission (usually within 3-4 months after starting cyclophosphamide) cyclophosphamide can be replaced by azathioprine with no increase in relapse rates if treatment is continued for at least 1 year. Methotrexate is inferior to cyclophosphamide because of increased relapse rates-particularly in those with renal involvement-during follow-up. An ongoing study comparing mycophenolate mofetil (MMF) with azathioprine will clarify whether MMF is as successful as azathioprine or even better. The concomitant use of tumor necrosis factor (TNF)-alpha blockers increases the efficacy of immunosuppression. TNF-alpha blockers may be added if SNV is refractory to standard immunosuppressive therapy. However, with this addition to therapy, systemic infections are more frequent. In patients with severe lupus nephritis (WHO IV) the efficacy of combined i.v. therapy with cyclophosphamide and glucocorticoids was shown by NIH trials. This NIH regimen competes with the EURO-Lupus nephritis schedule with a lower dose of i.v. cyclophosphamide followed by maintenance therapy with azathioprine. Long-term follow-up is, however, still lacking in the EURO-Lupus trial. Ongoing prospective studies will reveal whether cyclophosphamide may be substituted by MMF from the very beginning or whether MMF is superior to azathioprine during maintenance therapy of lupus nephritis.
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PMID:Cyclophosphamide treatment in systemic necrotizing vasculitis and lupus nephritis. How long? How much? 1525 54

Plasma concentration of TNF-alpha and its type I receptor (p55TNF-R) was examined in 126 patients with drug-induced skin reactions using immunoenzymatic ELISA method. Patients were subdivided into 6 groups: maculopapular eruptions (ME), erythema multiforme (EM), erythema multiforme coexisting with erythema nodosum (EMN), hyperergic vasculitis (HV), Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN). In the acute clinical stage highly significant (p<0.001) or significant (p<0.01) elevation of mean plasma concentrations of the cytokine and its receptor was found in all examined groups in comparison with the control. Clearing of clinical symptoms was connected with considerable decrease (p<0.001, p<0.01) of mean plasma levels of the both proteins in comparison with the before treatment values. TNF-alpha concentrations still remained significantly more elevated than those observed in the control. The results indicate that plasma activity of TNF-alpha and its p55 receptor change with the clinical course of the examined drug-induced skin reactions, which suggests the partake of both proteins in the pathogenesis of these diseases.
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PMID:Activity of Tumor Necrosis Factor-alpha (TNF-alpha) and its soluble type I receptor (p55TNF-R) in some drug-induced cutaneous reactions. 1532 66

Anesthetized rams envenomed s.c. with 40 microg/kg Tityus discrepans scorpion venom developed fasciculation, hypothermia, polyuria, pulmonary wet rales, tachypnea, respiratory distress and arrhythmia. Rams developed a cascade of inflammation reactions, characterized by activation of macrophages, fibroblasts and neutrophils, neutrophil infiltration and aggregation, vasculitis, arteritis and abundant fibrin deposition. At the inoculation site, venom was detected by immunohistochemistry in the extra cellular matrix, lymphatic vessels' and venules' lumen, inside macrophages and surrounding nerves. Extra cellular matrix was degraded at the inoculation site perhaps by activated neutrophils. Envenoming produced hepatocytes with Mallory body-like vacuoles which may be due to the increased plasmatic levels of TNF-alpha and IL6. Venom produced degranulation and vacuolization of acinary cells as well as interstitial swelling and necrosis. Necrosis of the Langerhan's islets occurred occasionally. Lungs showed the most deleterious effects developing wall collapse and necrosis, diffuse injury of the alveolar capillary barrier, interstitial and alveolar fibrin deposits with strong neutrophil infiltration. Massive infiltration of lymphocytes and macrophage occurred in the intestinal submucose, to the point that it modified villi and intestinal folding morphology. Envenomation developed a marked leukocyte aggregation surrounding nerves at the inoculation site. This study reveals that beyond its neurotoxicity, Tityus venom produces a severe and widespread inflammatory syndrome, expressed as histopathological changes at the site of inoculation, as well as in remote organs such as pancreas, lungs, intestine and liver. Our results suggest that not all remote targets are directly affected by the venom but that, as proposed earlier, are modified by inflammation by products produced elsewhere.
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PMID:Histopathological changes and inflammatory response induced by Tityus discrepans scorpion venom in rams. 1553 Sep 67

The present study has examined relationship between cutaneous microvessel injury and adhesion molecule expression on the endothelium by cytokines in NZBxNZWF1 (B/WF1) mice, a model for human systemic lupus erythematosus. In advanced ages associated with overt clinical manifestation, but not in early ages, neutrophils with a minor proportion of monocytes and lymphocytes mainly adhered to the endothelium of capillary and the venule with fragmentation (leukocytoclasis), leading to the vascular injury (leukocytoclastic vasculitis). This was confirmed by the leak of monstral blue from the blood vessel. At this stage LFA-1+ leukocytes adhered to intensely expressed ICAM-1 on the endothelium, and this was paralleled with a significant rise in IL-1 alpha and TNF-alpha in the circulation. The present study suggests that IL-1 alpha and TNF-alpha may, at least in part, be responsible for the increased ICAM-1 expression on endothelium in cutaneous microvessels, resulting in the vascular injury characterized by neutrophilic leukocytoclasis in B/WF1 mice.
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PMID:ICAM-1 expression on endothelium and systemic cytokine production in cutaneous neutrophilic leukocytoclastic vasculitis in NZBxNZWF1 mice. 1557 21

One of the most important questions in vasculitis research is not why inflammation of blood vessels occurs but why it persists, often in a site-specific manner. In this review we illustrate how stromal cells, such as fibroblasts and pericytes, might play an important role in regulating the site at which vasculitis occurs. Smooth muscle cells and fibroblasts directly influence the behaviour of overlying vascular cells, amplifying the response of the endothelium to proinflammatory agents such as TNF-alpha and allowing enhanced and inappropriate leucocyte recruitment. An abnormal local vascular stromal environment can therefore influence local endothelial function and drive the persistence of local vascular inflammation. However, such local vascular inflammation can have distant effects on the systemic vascular system, leading to widespread endothelial cell dysfunction. Vascular endothelial dysfunction is common in a range of immune-mediated inflammatory diseases, is seen in multiple vascular beds, and is reversible following the induction of disease remission. The mechanisms that drive such systemic vascular endothelial dysfunction are unclear but factors such as TNF-alpha and CRP may play a role. Persistence of such widespread endothelial dysfunction in systemic vasculitis appears to have long-term consequences, leading to the acceleration of atherosclerosis and premature ischaemic heart disease. It may also underlie the accelerated atherosclerosis seen in other immune-mediated rheumatic diseases, such as rheumatoid arthritis.
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PMID:Endothelial cells, fibroblasts and vasculitis. 1564 88

We report on successful induction of remission in a patient with necrotizing crescentic glomerulonephritis associated with myeloperoxidase-antineutrophil-cytoplasm antibodies by primary use of the anti-tumor necrosis factor (TNF)-alpha chimeric monoclonal antibody infliximab in combination with corticosteroids only. The standard treatment containing cyclophosphamide has reduced the former high mortality from systemic vasculitides. However, the toxicity of this alkylating agent limits its long-term use. As TNF-alpha has been shown to play a central pathogenic role in vasculitis as well as in crescentic glomerulonephritis, anti-TNF-alpha treatment in combination with cyclophosphamide has been found to be effective in therapy-resistant vasculitis. Previous reports on TNF-alpha-blocking therapies without additional cyclophosphamide did not include patients with active and severe crescentic glomerulonephritis. As our patient refused cyclophosphamide, he was given four infusions of infliximab (4 mg/kg on weeks 0, 2, 6 and 10) and methylprednisolone pulses (1 g on days 1-3), followed by daily oral prednisolone (starting with 2 mg/kg and tapering down to 5 mg daily within 3 months). After 12 weeks, control biopsy demonstrated lack of active glomerular inflammation while initially reduced renal function (creatinine 271 versus 172 mol/l, clearance 26 versus 62 ml/min) and proteinuria (2.4 versus 1.0 g/d) improved. Under remission maintenance therapy with azathioprine and prednisolone, the patient showed no relapses during a 1-year follow-up. Finally we demonstrate that there might be patients with crescentic glomerulonephritis who do not require therapy with alkylating substances and that less toxic agents such as the TNF-alpha-blocking monoclonal antibody infliximab could play a role in future primary treatment of crescentic glomerulonephritis.
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PMID:Crescentic glomerulonephritis associated with myeloperoxidase-antineutrophil-cytoplasmic antibodies: first report on the efficacy of primary anti-TNF-alpha treatment. 1564 40

High-dose corticosteroids in combination with cytotoxic drugs are universally accepted as the initial treatment in ANCA-associated vasculitis. Cyclophosphamide is the most effective cytotoxic drug and is used in more severe cases. Because of short- and long-term side-effects, novel therapies have been tested. New prospects for the treatment of vasculitis include sequential chemotherapy (e.g. cyclophosphamide followed by azathioprine or cyclophosphamide followed by methotrexate) and/or novel immunosuppressive agents (e.g. mycophenolate mofetil, anti-TNF-alpha).
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PMID:[New therapeutic strategies in ANCA-associated systemic vasculitis]. 1577 92

Intranasal infection of BALB/c mice with respiratory syncytial virus (RSV)-A2 (0.5 x 10(8) - 2.0 x 10(8) plaque-forming units, PFU) produced disease characterized by weight loss (2-3 g) and mortality (60%-100%) with the mean day of death ranging from 6-7 d after infection. The extent of RSV disease was inoculum titer-dependent and required a replication competent virus. Lung titers of virus peaked at 0.5-1 x 10(6) PFU/g wet weight. Bronchoalveolar lavage fluid (BALF) levels of IL-1beta, TNF-alpha, INF-gamma IL-12, IL-6, MIP-1alpha, RANTES, and protein were elevated, whereas IL-2, IL-4, IL-5, IL-13, and IL-10 were unchanged. Histological assessment of lungs revealed marked inflammatory pathology characterized by bronchiolitis, vasculitis, and interstitial pneumonia. Whole-body plethysmography revealed significant disease-associated deficits of respiratory function. Therapy with ribavirin administered either by the intranasal, subcutaneous, or oral route significantly reduced disease in a dose-dependent manner. Delaying the initiation of therapy resulted in a loss of activity for ribavirin. Synagis administered either intramuscularly as a single dose in prophylaxis or intranasally in prophylaxis, followed by therapy, also significantly reduced disease in a dose-dependent manner. Infection of mice with a high titer inoculum of RSV-A2 resulted in severe and fatal pulmonary disease that was responsive to treatment. This model may be useful to characterize the in vivo activity of experimental therapies for RSV infection.
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PMID:Primary infection of mice with high titer inoculum respiratory syncytial virus: characterization and response to antiviral therapy. 1579 Dec 94


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