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21.
Natriuretic peptides in unstable coronary artery disease. 总被引:1,自引:0,他引:1
Tomas Jernberg Stefan James Bertil Lindahl Nina Johnston Mats Stridsberg Per Venge Lars Wallentin 《European heart journal》2004,25(17):1486-1493
Patients with unstable coronary artery disease (CAD), i.e., unstable angina or non-ST-elevation myocardial infarction, vary widely in clinical presentation, prognosis and response to treatment. To select appropriate therapy, early risk stratification has become increasingly important. This review focuses on the emerging role of natriuretic peptides in the early assessment of patients with unstable CAD. We conclude that levels of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are strongly associated to mortality and the risk of future congestive heart failure, and carry important prognostic information independent from previously known risk factors in unstable CAD. There are some data indicating that these markers can also be helpful in the selection of appropriate therapy in these patients but further studies are needed. Before a routine use of BNP or NT-proBNP in unstable CAD can be recommended, the cost-effectiveness of adding these new markers to the currently routine markers and their impact on selection of treatment needs further evaluation. 相似文献
22.
Background
Despite improved laboratory assays for cardiac markers and a revised standard for definition of myocardial infarction (AMI), early detection of coronary ischemia in unselected patients with chest pain remains a difficult challenge.Methods
Rapid measurements of troponin I (TnI), creatine kinase MB (CK-MB), and myoglobin were performed in 197 consecutive patients with chest pain and a nondiagnostic electrocardiogram for AMI. The early diagnostic performances of these markers and different multimarker strategies were evaluated and compared. Diagnosis of AMI was based on European Society of Cardiology/American College of Cardiology criteria.Results
At a given specificity of 95%, TnI yielded the highest sensitivity of all markers at all time points. A TnI cutoff corresponding to the 10% coefficient of variation (0.1 μg/L) demonstrated a cumulative sensitivity of 93% with a corresponding specificity of 81% at 2 hours. The sensitivity was considerably higher compared to CK-MB and myoglobin, even considering patients with a short delay until admission. Using the 99th percentile of TnI results as a cutoff (0.07 μg/L) produced a cumulative sensitivity of 98% at 2 hours, but its usefulness was limited due to low specificities. Multimarker strategies including TnI and/or myoglobin did not provide a superior overall diagnostic performance compared to TnI using the 0.1 μg/L cutoff.Conclusion
A TnI cutoff corresponding to the 10% coefficient of variation was most appropriate for early diagnosis of AMI. A lower TnI cutoff may be useful for very early exclusion of AMI. CK-MB and in particular myoglobin did not offer additional diagnostic value. 相似文献23.
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25.
Taskinen M Westerholm-Ormio M Karikoski R Lindahl H Veres G Savilahti E Saarinen-Pihkala UM 《Bone marrow transplantation》2004,34(3):221-228
Intestinal immunopathology was studied after allogeneic stem cell transplantation (SCT) in a common clinical setup in 20 children with malignant (n=17) or nonmalignant diseases (n=3) receiving grafts from siblings (7) and unrelated donors (13). In all, 19 had total body irradiation. Duodenal biopsies at 6 and 12 weeks post transplant were evaluated by histology, immunohistochemistry, and ISEL for the detection of T-lymphocytes, inflammatory cytokines, proliferation, and apoptosis. The controls were 12 healthy children and three patients with proven intestinal graft-versus-host disease. An increased rate of apoptosis and proliferation with upregulated expression of HLA-DR antigen was detected up to 3 months post transplant in the SCT patients, even in those with a histologically normal small intestine. A low level of IFNgamma and TNFalpha was observed in the lamina propria. The initial low density of gammadelta-positive T cells had recovered to normal by the time of the second endoscopy at 12 weeks post transplant. We conclude that inflammatory activity and T cell infiltration detected by immunohistochemistry may not belong to the 'normal' recovery of the small intestine after SCT. Increased cell turnover in the intestinal crypts continues until 3 months after SCT, suggesting either an unexpectedly long-lasting effect of transplant-related toxicity or, preferably, an ongoing subclinical alloreactive process, also present in the patients without intestinal symptoms. 相似文献
26.
Pancreas Transplantation With Enteroanastomosis to Native Duodenum Poses Technical Challenges—But Offers Improved Endoscopic Access for Scheduled Biopsies and Therapeutic Interventions 下载免费PDF全文
R. Horneland V. Paulsen J. P. Lindahl K. Grzyb T. J. Eide K. Lundin L. Aabakken T. Jenssen E. M. Aandahl A. Foss O. Øyen 《American journal of transplantation》2015,15(1):242-250
To facilitate endoscopic access for rejection surveillance and stenting of the pancreas, we have abandoned the duodenojejunostomy (DJ) in favor of duodenoduodenostomy (DD) in pancreas transplantation (PTx). From September 2012 to September 2013 we performed 40 PTx with DD; 20 solitary‐PTx (S‐PTx) and 20 simultaneous pancreas and kidney transplantation (SPK). We compared the outcomes with results from 40 PTx‐DJ (10 S‐PTx and 30 SPK) from the preceding era. The DD‐enteroanastomoses were performed successfully. Endoscopic pancreas biopsies (endoscopic ultrasound examination [EUS]) yielded representative material in half of the cases. One exocrine fistula was treated by endoscopic stenting. PTxs‐DD were associated with a higher rate of thrombosis compared to PTx‐DJ (23% vs. 5%) and reoperations (48% vs. 30%), as well as inferior graft survival (80% vs. 88%). Time on waiting list, HLA A + B mismatches and reoperations were associated with graft loss. Only recipient age remained an independent predictor of patient death in multivariate analysis. PTx‐DD showed a higher rate of thrombosis and inferior results, but facilitated a protocol biopsy program by EUS that was feasible and safe. Given that technical difficulties can be solved, the improved endoscopic access might confer long‐term benefits, yet this remains to be proven. 相似文献
27.
Mechanisms behind the prognostic value of troponin T in unstable coronary artery disease: a FRISC II substudy 总被引:4,自引:0,他引:4
Lindahl B Diderholm E Lagerqvist B Venge P Wallentin L;FRISC II 《Journal of the American College of Cardiology》2001,38(4):979-986
OBJECTIVES: This study was designed to elucidate possible mechanisms for the prognostic value of troponin T (tnT). BACKGROUND: The reasons for the adverse prognosis associated with elevation of troponins in unstable coronary artery disease are poorly understood. METHODS: Patients enrolled in the Fast Revascularization during InStability in CAD (FRISC-II) trial were included. Clinical characteristics, findings at echocardiography and coronary angiography, and prognosis were evaluated in relation to different tnT levels. RESULTS: Absence of significant coronary stenosis was more frequent and three-vessel disease or left main stem stenosis was less frequent in patients without, compared with, detectable tnT. The occurrence of visible thrombus increased with rising levels of tnT. In the group with the highest levels of tnT, occlusion of the left circumflex artery was more common than in the three other tnT groups, as was a left ventricular ejection fraction below 0.45. The one-year risk of death in the noninvasive arm of the study increased by increasing levels of tnT (1.6% to 4.6%), whereas the risk of myocardial infarction showed an inverted U-shaped curve and was lower in the lowest (5.5%) and highest (8.4%) tnT groups than in the two intermediate groups (17.5% and 16.2%). CONCLUSIONS: Any detectable elevation of tnT raises the probability of significant coronary stenosis and thrombus formation and is associated with an increased risk of reinfarction and death. However, at a more pronounced elevation of troponin, a higher proportion of patients has a persistent occlusion of the culprit vessel and reduced left ventricular function, associated with a high mortality but a modest risk of reinfarction. 相似文献
28.
A Naggi G Torri B Casu P Oreste G Zoppetti J P Li U Lindahl 《Seminars in thrombosis and hemostasis》2001,27(5):437-443
A process to generate glycosaminoglycans with heparin- and heparan sulfate-like sequences from the Escherichia coli K5 capsular polysaccharide is described. This polymer has the same structure as N-acetylheparosan, the precursor in heparin/ heparan sulfate biosynthesis. The process involves chemical N-deacetylation and N-sulfation, enzymatic conversion of up to 60% of the D-glucuronic acid to L-iduronic acid residues, and chemical O-sulfation. Because direct sulfation afforded unwanted 3-O-sulfated (instead of 2-O-sulfated) iduronic acid residues, a strategy involving graded solvolytic desulfation of chemically oversulfated C5-epimerized sulfaminoheparosans was assessed using persulfated heparin and heparan sulfate as model compounds. The O-desulfation process was shown to increase the anti-factor Xa activity of oversulfated heparin. 相似文献
29.
30.
Karin G. Stenkula Maria Lindahl Jitka Petrlova Jonathan Dalla-Riva Olga Göransson Samuel W. Cushman Ewa Krupinska Helena A. Jones Jens O. Lagerstedt 《Diabetologia》2014,57(4):797-800