Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hydrated fibrin gels were studied by confocal laser 3D microscopy, liquid permeation and turbidity. The gels from normal fibrinogen were found to be composed of straight rod-like fiber elements which sometimes originated from denser nodes. In gels formed at increasing thrombin or fibrinogen concentrations, the gel networks became tighter and the porosity decreased. The fiber strands also became shorter. Gel porosity of the network decreased dramatically in gels formed at increasing ionic strengths. Shortening of the fibers were observed and fiber swelling occurred at ionic strength above 0.24. Albumin and dextran, when present in the gel forming system, affected the formation of more porous structures with strands of larger mass-length ratio and fiber thickness. This type of gels were also formed in plasma. Albumin and lipoproteins may be among the determinants for the formation of this type of gel structure in plasma. Gels formed when factor XIIIa instead of thrombin was used as catalyst for gelation showed a completely different structure in which lumps of polymeric material were held together by a network of fine fiber strands. Our studies have also shown that the methodologies employed may be useful in studies of gel structures in certain dysfibrinogenemias as well as in other diseases. We give examples of two patients with abnormal fibrinogen and of patients with ischaemic heart disease.
 ...
PMID:Native fibrin gel networks and factors influencing their formation in health and disease. 212 66

Superoxide Dismutase has been reported to offer important pharmacological advantages in modifying oxygen toxicity as a result of its ability to scavenge oxygen free radicals. This has proven most exciting in reducing damage associated with post-reperfusion damage following myocardial ischemia. Unfortunately Superoxide Dismutase has a circulation life time of only a few minutes making the exact time of its administration crucial and somewhat impractical. We report here on the production of SOD-Albumin conjugates which have important advantages over free SOD in terms of stability, extended circulation time and reduced immunogenicity.
 ...
PMID:Superoxide dismutase: improving its pharmacological properties by conjugation with human serum albumin. 281 54

Albumin excretion in urine is positively correlated with the presence of ischemic heart disease and atherosclerotic risk factors. We studied prospectively whether a slight increase of urinary albumin excretion, ie, microalbuminuria, adds to the increased risk of ischemic heart disease among hypertensive subjects. In 1983 and 1984, blood pressure, urinary albumin/creatinine concentration ratio, plasma total and HDL cholesterol levels, body mass index, and smoking status were obtained in a population-based sample of 2085 subjects, aged 30 to 60 years, who were free from ischemic heart disease, diabetes mellitus, and renal or urinary tract disease. Untreated arterial hypertension or borderline hypertension was present in 204 subjects, who were followed until 1993 by the National Hospital and Death Certificate Registers with respect to development of ischemic heart disease. During 1978 person-years, 18 (9%) of the hypertensive subjects developed ischemic heart disease. Microalbuminuria, defined as a urinary albumin/creatinine ratio above the upper decile (1.07 mg/mmol), was the strongest predictor of ischemic heart disease, with an unadjusted relative risk of 4.2 (95% CI 1.5 to 11.9, P=0.006) and a relative risk of 3.5 (95% CI 1.0 to 12.1, P=0.05) when adjusted for all other atherosclerotic risk factors, including age and gender. In conclusion, microalbuminuria confers a 4-fold increased risk of ischemic heart disease among hypertensive or borderline hypertensive subjects. Urinary albumin excretion should be measured regularly in a hypertension clinic, and a rigorous control of blood pressure and of other atherosclerotic risk factors is recommended in hypertensive patients with microalbuminuria.
 ...
PMID:Arterial hypertension, microalbuminuria, and risk of ischemic heart disease. 1077 58

Human albumin has the ability to bind cobalt at the N-terminus. The exposure of circulating albumin to ischemic tissue alters the ability of albumin to bind cobalt, probably through a mechanism involving free-radical production. The Albumin Cobalt Binding (ACB) test measures the alteration in albumin metal binding, and elevation of the ACB test is thought to be an early indicator of myocardial ischemia. In a previous multicenter study of chest pain patients presenting to the emergency department (ED), this test demonstrated high negative predictive value and sensitivity in the sample collected at presentation for predicting cardiac troponin I (cTnI)-negative or cTnI-positive results 6-24 h later. Since the completion of that report, the European Society of Cardiology (ESC) and the American College of Cardiology (ACC) have redefined the criteria for the diagnosis of acute myocardial infarction (AMI). The data from the multicenter ACB study were re-examined using the new diagnostic criteria for AMI to determine if combining the ACB test with troponin improved the sensitivity of either assay used alone for early diagnosis of AMI. Assay values were compared to either the final discharge diagnosis made at each site or to a diagnosis of AMI using the strict application of the ESC/ACC guidelines. Using the criterion of physician's discharge diagnosis and using blood collected at ED presentation, the cTnI test alone had a sensitivity of 23.9%, and the ACB test alone had a sensitivity of 39.1%, but the sensitivity significantly increased to 55.9% (p < 0.001 over cTnI alone) when both tests were used in combination. The sensitivity of the combination of ACB and cTnI tests at the 1- to 6-h time-point was 86.7% and at the >6- to 12-h time-point was 93.5%, but they were not significantly improved over the cTnI test alone. In conclusion, using the new ESC/ACC criteria, the combination also resulted in a statistically significant higher diagnostic sensitivity on blood collected at presentation. These data indicate a possible role of the ACB test in the early triage of patients with chest pain.
 ...
PMID:Analysis of the Albumin Cobalt Binding (ACB) test as an adjunct to cardiac troponin I for the early detection of acute myocardial infarction. 1221 87

Recently a new biological marker, Ischemia Modified Albumin (IMA), measured by the Albumin Cobalt Binding (ACB) test, was introduced for detection of myocardial ischemia. During ischemia, the metal binding capacity of albumin for certain transition metals like cobalt is reduced. The precise mechanism of action for producing IMA is not known but appears to be related to the production of reactive oxygen species that modify the metal binding sites. The ACB test is a quantitative assay that detects IMA by measuring the cobalt binding capacity of albumin in human serum. We evaluated the analytical characteristics of the ACB test, and reagent and specimen stability, using the Cobas MIRA Plus instrument. Coefficients of variation for within-run and between-run assays were <4%. No significant interference was observed for concentrations of triglycerides and hemoglobin up to 7 mmol/l and 3.8 g/l, respectively. No interference was apparent with bilirubin. Measures from paired samples of heparinized plasma and serum were not equivalent. The assay is validated for commercial use with serum, therefore our study reported results for serum specimens only. All assays were completed within 5 hours after blood withdrawal. The one-sided upper 95th percentile, calculated for the ACB test in 150 healthy subjects, was 87.00 U/ml. There was no observed difference between men and women or with age. We conclude that the ACB test adapted on the Cobas MIRA Plus analyzer is satisfactory, but strict attention to sample handling procedures is necessary to maintain stability of the analyte.
 ...
PMID:Analytical performance of the Albumin Cobalt Binding (ACB) test on the Cobas MIRA Plus analyzer. 1514 58

We studied the role of ischemia-modified albumin (IMA) with standard biomarkers (myoglobin, creatine kinase-MB [CK-MB], troponin I [TnI]) in assessment of 200 patients with suspected myocardial ischemia admitted to the emergency department. Every case was reviewed by a cardiologist. A clinical diagnosis of ischemia was assigned and correlated with biomarker test results. Of the patients, 25 (13.0%) had myocardial ischemia. Receiver operating characteristic curves demonstrated IMA as highly sensitive but somewhat poorly specific for the presence of ischemia (area under curve, 0.63; P = .01). With a cut point of 90 U/mL, the Albumin Cobalt Binding Test had 80% sensitivity and 31% specificity for diagnosing ischemia and a negative predictive value of 92%. IMA was positive in 4 of 5 patients with electrocardiographic (ECG) evidence of ischemia and 16 of 20 patients with coronary ischemia but negative ECG. Among the same patients, the myoglobin-CK-MB-TnI triad had a sensitivity of 57%. The combination of IMA-myoglobin-CK-MB-TnI increased the sensitivity for detecting ischemia to 97%, with a negative predictive value of 92%. IMA is highly sensitive and has a high negative predictive value, which might improve the usefulness of standard biomarkers of myocardial ischemia.
 ...
PMID:Ischemia-modified albumin improves the usefulness of standard cardiac biomarkers for the diagnosis of myocardial ischemia in the emergency department setting. 1627 Apr 50

The biochemical marker of myocardial ischemia is detected prior to the development of myocardial necrosis, i.e. a novel biochemical evaluation based on human serum albumin binding to cobalt, a transitional metal. The evaluation is known as Albumin Cobalt Binding (ACB) Test. ACB Test is applied to detect the presence of Ischemia Modified Albumin (IMA), an albumin which has altered binding capacity to bind metal ion such as cobalt (Co), copper (Cu) and nickel (Ni) in N-terminus region. It is produced when the serum albumin convenes with ischemic heart tissues. ACB Test detecting the presence of myocardial ischemia that occurs prior to myocardial necrosis has been studied by some researchers and they found an ACB increase prior to troponin increase. The cut off point of ACB evaluation was 85 U/ml. Provided that the value was greater than 85 U/ml then there was positive myocardial ischemia. But it should be noticed that IMA increase in the plasma may be due to other tissues such as gastrointestinal tissues or skeletal muscles tissues. We should also consider other factors which may affect the evaluation result such as severe hypoalbuminemia that will cause a false-high result. ACB Test may be used as an early marker of myocardial ischemia that occurs prior to myocardial necrosis.
 ...
PMID:Albumin cobalt binding (ACB) test: its role as a novel marker of acute coronary syndrome. 1679 11

The prevalence and significance of microalbuminuria in hypertensive patients with impaired fasting glucose (IFG) has received very little attention. A total of 10,320 hypertensive patients who attended primary care centers were enrolled in this study, and the final analysis was done in 7625 patients: 1459 without IFG (plasma glucose <100 mg/dl), 3010 with IFG (plasma glucose > or =100 mg/dl and <126 mg/dl), and 3156 with type 2 diabetes (plasma glucose >126 mg/dl). Microalbuminuria was determined using the Micro Albustix reactive strip from Bayer (high urinary albumin excretion [UAE]: Albumin/creatinine ratio > or =3.4 mg/mmol). The proportion of patients with high UAE was 39.4, 48.3, and 65.6%, respectively, in the three groups (P < 0.01 for the trend). The differences in UAE between the group with IFG and the group with normal fasting glucose persisted after adjustment for age, gender, systolic BP, fasting plasma glucose, and cardiovascular comorbidity (odds ratio 1.74; 95% confidence interval 1.08 to 2.80). Hypertensive patients with IFG and high UAE showed a higher prevalence of ischemic heart disease, cardiac insufficiency, left ventricular hypertrophy, atrial fibrillation, and renal insufficiency than the group with normal UAE. Global prevalence of cardiovascular conditions was 30.4% in the group with high UAE compared with 21.4% in the group with normal UAE (odds ratio 1.60; 95% confidence interval 1.31 to 1.95). It is concluded that almost half of hypertensive patients with IFG have high UAE and a higher prevalence of associated cardiovascular involvement and renal insufficiency.
 ...
PMID:Prevalence of abnormal urinary albumin excretion rate in hypertensive patients with impaired fasting glucose and its association with cardiovascular disease. 1713 Feb 59

Verification of the diagnosis of coronary artery disease (CAD) is based mostly on instrumental diagnostic techniques. Presently, there are no laboratory tests officially recommended for the diagnostics of myocardial ischemia (MI). Biochemical methods that would be able to verify MI in patients with suspected CAD have been under development since the 1990s. Ischemically modified albumin--IMA (Albumin Cobalt Binding test), glycogen phosphorylase BB, and free fatty acid-binding protein have been proposed as laboratory markers of MI. The article discusses advantages and disadvantages of IMA for diagnostics of MI in patients with acute coronary syndrome.
 ...
PMID:[Albumin cobalt binding ability in assessment of myocardial ischemia in patients with acute coronary syndrome]. 1849 85

Myocardial ischemia is difficult to diagnose effectively with still few well-defined biochemical markers for identification in advance, or in the absence of myocardial necrosis. "Ischemia-modified albumin" (IMA), a form of albumin displaying reduced cobalt-binding affinity, is significantly elevated in ischemic patients, and the albumin cobalt-binding (ACB) assay can measure its level indirectly. Elucidating the molecular mechanism underlying the identity of IMA and the ACB assay hinges on understanding metal-binding properties of albumin. Albumin binds most metal ions and harbours four primary metal binding sites: site A, site B, the N-terminal site (NTS), and the free thiol at Cys34. Previous efforts to clarify the identity of IMA and the causes for its reduced cobalt-binding capacity were focused on the NTS site, but the degree of N-terminal modification could not be correlated to the presence of ischemia. More recent work suggested that Co2+ ions as used in the ACB assay bind preferentially to site B, then to site A, and finally to the NTS. This insight paved the way for a new consistent molecular basis of the ACB assay: albumin is also the main plasma carrier for free fatty acids (FFAs), and binding of a fatty acid to the high-affinity site FA2 results in conformational changes in albumin which prevent metal binding at site A and partially at site B. Thus, this review advances the hypothesis that high IMA levels in myocardial ischemia and many other conditions originate from high plasma FFA levels hampering the binding of Co2+ to sites A and/or B. This is supported by biophysical studies and the co-association of a range of pathological conditions with positive ACB assays and high plasma FFA levels.
 ...
PMID:Ischemia-modified albumin: Crosstalk between fatty acid and cobalt binding. 3010 26


1 2 Next >>