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11.
Generation of complement C3 and expression of cell membrane complement inhibitory proteins by human bronchial epithelium cell line 下载免费PDF全文
BACKGROUND: The interrelationship between human airway epithelium and complement proteins may affect airway defence, airway function, and airway epithelial integrity. A study was undertaken to determine (1) whether unstimulated human bronchial epithelium generates complement proteins and expresses cell membrane complement inhibitory proteins (CIP) and (2) whether stimulation by proinflammatory cytokines affects the generation of complement and expression of cell membrane CIP by these cells. METHODS: Human bronchial epithelium cell line BEAS-2B was cultured in a serum-free medium. Cells were incubated with and without proinflammatory cytokines to assess unstimulated and stimulated generation of complement C3, C1q and C5 (by ELISA), and to examine the expression of cell membrane CIP decay accelerating factor (DAF; CD55), membrane cofactor protein (MCP; CD46), and CD59 (protectin) by flow cytometry analysis. RESULTS: Unstimulated human bronchial epithelial cell line BEAS-2B in serum-free medium generates complement C3 (mean 32 ng/10(6) cells/72 h, range 18-52) but not C1q and C5, and expresses cell membrane DAF, MCP, and CD59. Interleukin (IL)-1alpha (100 U/ml/72 h) and tumour necrosis factor (TNF-alpha; 1000 U/ml/72 h) increased generation of C3 up to a mean of 78% and 138%, respectively, above C3 generation by unstimulated cells. DAF was the only cell membrane CIP affected by cytokine stimulation. Interferon (IFN)-gamma (10 U/ml/72 h) and TNF-alpha (1000 U/ml/72 h) increased DAF expression up to a mean of 116% and 45%, respectively, above that in unstimulated cells. MCP and CD59 expression was not consistently affected by IL-1alpha, TNF-alpha, or IFN-gamma. CONCLUSIONS: Local generation of complement C3 and expression of cell membrane CIP by human bronchial epithelium and its modulation by proinflammatory cytokines might be an additional regulatory mechanism of local airway defence and may affect airway function and epithelial integrity in health and disease. 相似文献
12.
nNOS inhibitors attenuate methamphetamine-induced dopaminergic neurotoxicity but not hyperthermia in mice 总被引:5,自引:0,他引:5
Methamphetamine (METH)-induced dopaminergic neurotoxicity is associated with hyperthermia. We investigated the effect of several neuronal nitric oxide synthase (nNOS) inhibitors on METH-induced hyperthermia and striatal dopaminergic neurotoxicity. Administration of METH (5 mg/kg; q. 3 h x 3) to Swiss Webster mice produced marked hyperthermia and 50-60% depletion of striatal dopaminergic markers 72 h after METH administration. Pretreatment with the nNOS inhibitors S-methylthiocitrulline (SMTC; 10 mg/kg) or 3-bromo-7-nitroindazole (3-Br-7-NI; 20 mg/kg) before each METH injection did not affect the persistent hyperthermia produced by METH, but afforded protection against the depletion of dopaminergic markers. A low dose (25 mg/kg) of the nNOS inhibitor 7-nitroindazole (7-NI) did not affect METH-induced hyperthermia, but a high dose (50 mg/kg) produced significant hypothermia. These findings indicate that low dose of selective nNOS inhibitors protect against METH-induced neurotoxicity with no effect on body temperature and support the hypothesis that nitric oxide (NO) and peroxynitrite have a major role in METH-induced dopaminergic neurotoxicity. 相似文献
13.
Brook I 《American journal of perinatology》2008,25(2):111-118
Necrotizing enterocolitis (NEC) is a clinical syndrome of ischemic necrosis of the bowel of multiple etiological factors that include the presence of intestinal ischemia, abnormal bacterial flora, and intestinal mucosal immaturity. Numerous reports have implied that the fecal microflora may contribute to the pathogenesis of NEC. A broad range of organisms generally found in the distal gastrointestinal tract have been recovered from the peritoneal cavity and blood of infants with NEC. The predominant organisms include Enterobacteriaceae (i.e., Escherichia coli, Klebsiella pneumoniae) , Clostridium spp., enteric pathogens (salmonellae, Coxsackie B2 virus, coronavirus, rotavirus), and potential pathogens (Bacteroides fragilis). The goals of the initial management is preventing ongoing damage, restoring hemostasis, and minimizing complications. Medical management includes withholding oral feeding, placement of nasogastric tube, abdominal decompression, paracentesis, vigorous intravenous hydration containing electrolytes and calories, support of the circulation, administration of antibiotics, and surveillance for deterioration or complications that require surgical intervention. Indications for surgery include clinical deterioration, perforation, peritonitis, obstruction, and abdominal mass. Prevention remains crucial to decrease the incidence of NEC. Preventive methods include cautious feeding regimens, the use of maternal breast milk, and the use of probiotics. 相似文献
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15.
Acetyl phosphate is a central metabolite involved in a broad range of versatile cellular functions. Recently it was observed that in Escherichia coli the acetyl phosphate pathway is required for efficient ATP-dependent proteolysis. Deletion of the operon coding for acetyl phosphate metabolism (ΔackApta) results in a very low cytoplasmic level of acetyl phosphate and impaired proteolysis. Here we show that the ΔackApta mutation affects additional components of the protein quality control system. Thus, this deletion is accompanied by a decrease in protein refolding and rescue from aggregates. These results indicate the involvement of the acetyl phosphate pathway in chaperone capabilities, in addition to their effect on proteolysis. 相似文献
16.
Rozenbaum M Naschitz JE Yudashkin M Sabo E Shaviv N Gaitini L Zuckerman E Yeshurun D Rosner I 《Rheumatology international》2004,24(3):147-152
Objective The aim of this study was to assess the presence of dysautonomia, as manifested in abnormal cardiovascular reactivity, in patients with familial Mediterranean fever (FMF).Methods Fifty-five consecutive patients with FMF and 23 age- and sex-matched healthy controls were evaluated. Cardiovascular reactivity was studied: (1) using recordings of blood pressure (BP) and heart rate (HR) during 10 min of recumbence and 30 min of head-up tilt test to identify clinical endpoints and (2) during tilt-test, identifying parameters acting as independent predictors of FMF reactivity and enabling computation of a cardiovascular reactivity score (CVRS).Results Clinically, vasovagal reaction, postural tachycardia syndrome, and/or orthostatic hypotension were observed in ten patients (18.1%). Utilizing a derived equation, the group average CVRS in FMF was 5.83±1.78 (healthy group –7.60±5.41) (P=<0.0001). A CVRS of >3.25 was associated with FMF, with 98% sensitivity and 100% specificity.Conclusion A very high percentage of FMF patients exhibit abnormal cardiovascular reactivity which is clinically occult but can be detected on autonomic challenge and application of the CVRS. 相似文献
17.
Clinical evidence for utilization of the A3 adenosine receptor as a target to treat rheumatoid arthritis: data from a phase II clinical trial 总被引:1,自引:0,他引:1
Silverman MH Strand V Markovits D Nahir M Reitblat T Molad Y Rosner I Rozenbaum M Mader R Adawi M Caspi D Tishler M Langevitz P Rubinow A Friedman J Green L Tanay A Ochaion A Cohen S Kerns WD Cohn I Fishman-Furman S Farbstein M Yehuda SB Fishman P 《The Journal of rheumatology》2008,35(1):41-48
OBJECTIVE: Adenosine exerts antiinflammatory effects via activation of the A3 adenosine receptor (A3AR), a Gi protein-associated cell-surface receptor, overexpressed in synovial tissue and peripheral blood mononuclear cells (PBMC) in patients with active rheumatoid arthritis (RA). CF101 is a highly specific orally bioavailable A3AR agonist. METHODS: This was a multicenter study, blinded to dose, designed to assess the clinical activity and safety of CF101 in active RA. Seventy-four patients were randomized to receive 0.1, 1.0, or 4.0 mg CF101 bid for 12 weeks. The primary efficacy endpoint was American College of Rheumatology 20% response (ACR20) at Week 12. A3AR expression levels were analyzed in PBMC from 18 patients. RESULTS:. Maximal responses were observed with 1.0 mg bid, lower at 0.1 and 4.0 mg bid. At 12 weeks, 55.6%, 33.3%, and 11.5% of the patients receiving 1.0 mg CF101 achieved ACR20%, 50%, and 70% responses, respectively. CF101 was generally well tolerated, with mild headache (4.1%), nausea (2.7%), and rash (2.7%) being the most common treatment-related adverse events. Statistically significant correlations between A3AR overexpression at baseline and ACR50 and ACR70 responses were observed. CONCLUSION: CF101 administered bid for 12 weeks resulted in improvement in signs and symptoms of RA that did not achieve statistical significance, and was safe and well tolerated. The expression level of A3AR was directly correlated with patient responses to CF101, suggesting its utilization as a biomarker for the pharmacodynamic and therapeutic effects of this novel agent. These findings require confirmation in a double-blind randomized placebo-controlled trial, currently under way. 相似文献
18.
19.
Biological warfare is intended to incapacitate a large number of individuals at a single exposure, creating epidemictype disease,
death, and social chaos. The organisms with potential for immediate use as bacteriologic weapons are Bacillus anthracis, Brucella melitensis, Yersinia pestis, and Vibrio cholera, all necessitating antibiotic therapy for a cure. It is reasonable, therefore, to assume that a biological attack, or even
a hoax, would requiure thousands of individuals over a large area to begin antibiotic therapy. Issues such as antibiotic availability,
logistical problems in antibiotic distribution, development of drug resistance, side effects influencing the individual, and
adverse effects on the community due to the impact of mass therapy on the ecology, make biological warfare the most apocalyptic
scenario for the creation of a "postantibiotic era." 相似文献
20.
Opinion statement |
相似文献
– | To date, there are no evidence-based data to support specific drug therapy for a patient with atheroembolism. It makes sense to use HMG CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase inhibitors (statins) in any patient with atherosclerosis, as these drugs have been shown to reduce the risk of myocardial infarction and stroke, and have a theoretical benefit on plaque stabilization. Surgical treatment should be considered for patients with abdominal aortic or popliteal artery aneurysms and downstream atheroembolism. There are case reports of atheroemboli in patients worsening after given warfarin or heparin. For this reason, some institutions are reluctant to prescribe these drugs for patients with atheroemboli or thromboemboli from aortic plaque. However, the incidence of this complication is quite low. Anticoagulation probably should be stopped if a patient develops atheroembolism. |
– | Similarly, the current state of knowledge does not allow for selecting specific pharmacologic intervention in patients with thromboemboli from aortic plaque. Statin therapy does make sense, as these drugs theoretically stabilize plaques and prevent plaque hemorrhage, thrombosis, and subsequent embolization. Unstable aortic plaques may develop superimposed thrombi (red thrombi on pathologic examination), easily seen as mobile elements on transesophageal echocardio-graphy. Therefore, it is possible that anticoagulation with warfarin might prevent embolic events in these patients. For this reason, we are often in the position of recommending warfarin therapy for patients with emboli and severe atheromas seen on transesophageal echocardiography, especially when superimposed mobile thrombi are seen. There are small series in the literature that indicate the potential benefit of warfarin. However, until a large multicenter randomized clinical trial is done, the use of warfarin can not be definitively recommended. Antiplatelet agents, although safer than warfarin (less risk of hemorrhage), have not been proven beneficial in patients with thromboembolism from the aorta. Surgery (endarterectomy) of the aortic arch is a very risky procedure that should not be performed routinely, but may be used in highly selected patients. |