OBJECTIVETo identify and characterize the polypeptides specifically binding to human B type natriuretic peptide (BNP) screened from 12TM phage display peptide library.

METHODSThe BNP-binding peptides were screened from 12TM phage display peptide library and identified by ELISA.

RESULTSAfter 4 rounds of screening, 10 of the 16 phage clones were identified as the positive clones which could bind to BNP. Five amino acid sequences were obtained in the 10 positive clones. Dose-dependent ELISA results demonstrated that the screened polypeptides could specifically bind to BNP.

CONCLUSIONThese screened polypeptides can bind specifically to BNP, which provides a basis for further research on expression and purification of anti-BNP polypeptides and the development of the detection kit of BNP.

Humans ; Natriuretic Peptide, Brain ; metabolism ; Peptide Library ; Peptides ; analysis ; isolation & purification ; metabolism ; Protein Binding

China ; Female ; Heart Failure ; diagnosis ; drug therapy ; metabolism ; Humans ; Male ; Natriuretic Peptide, Brain ; analysis ; Peptide Fragments ; analysis

BACKGROUNDN-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) are excellent biomarkers for detecting heart failure and subclinical myocardial injury. However, it remains unclear whether subclinical myocardial injury is associated with NT-proBNP elevation in a community based population.

METHODSIn a community based study, levels of hs-cTnT and of NT-proBNP were determined in 1 497 participants older than 45 years. The lower detection limit of the hs-cTnT assay used in the present study was 0.003 ng/ml. The association of hs-cTnT levels and NT-proBNP levels was analyzed.

RESULTSWhen the subjects with undetectable (<0.003 ng/ml), intermediate (0.003-0.014 ng/ml), and elevated (≥0.014 ng/ml) levels of hs-cTnT were compared (r = 0.175, P < 0.001), a strong association between the hs-cTnT levels and NT-proBNP levels was observed (β = -0.206, P < 0.001; β = -0.118, P < 0.001, respectively). In multivariable analyses, older age and hs-cTnT were positively and independently associated with NT-proBNP levels (β = 0.341, P < 0.001; β = 0.143, P < 0.001, respectively), and male gender and the levels of eGFR were inversely and independently associated with NT-proBNP levels. When the subjects with normal or elevated NT-proBNP were analyzed separately, the hs-cTnT level was not an independent predictor for the NT-proBNP level in the normal NT-proBNP group, whereas the hs-cTnT level was the only independent predictor for NT-proBNP level in the elevated NT-proBNP group (β = 0.399, P < 0.01).

CONCLUSIONSIn this community based population, NT-proBNP elevation was common. In addition to female gender and older age, subclinical myocardial injury indicated by the hs-cTnT level was another important factor in NT-proBNP elevation.

Biomarkers ; analysis ; Female ; Humans ; Male ; Middle Aged ; Natriuretic Peptide, Brain ; blood ; Peptide Fragments ; blood ; Troponin T ; blood

Animals ; Brain Injuries ; blood ; cerebrospinal fluid ; chemically induced ; Endotoxins ; toxicity ; Female ; Male ; Natriuretic Peptide, C-Type ; analysis ; Neurotensin ; analysis ; Rabbits

BACKGROUND/AIMS: No studies have conclusively determined whether the B-type natriuretic peptide (BNP) level measured before electrical cardioversion for atrial fibrillation (AF) is associated with the maintenance of sinus rhythm after the procedure. Therefore, we investigated whether the plasma BNP can predict AF recurrence in the short-term. METHODS: We prospectively recruited 20 consecutive patients with persistent AF, without symptomatic congestive heart failure. The plasma BNP was measured before and after electrical cardioversion. RESULTS: In all patients, AF was converted to normal sinus rhythm (NSR) after the procedure. NSR was maintained in 70.0% of the patients at 1 week and in 52.6% of the patients at 4 weeks. Of the patients with NSR at 1 week, five patients had relapsed by 4 weeks (4-week relapse group, 4WRG). The log BNP levels after cardioversion decreased significantly in all patients, except for the failed group at 1 week and the 4WRG. Multivariate analysis revealed that the maintenance of sinus rhythm was associated with body mass index at 1 week, and left atrial diameter (LAD) and left ventricular mass index (LVMI) at 4 weeks. 4WRG had a significantly higher baseline BNP. The baseline BNP was associated with the LVMI (R2=0.241, p=0.028) and tissue Doppler imaging (TDI) E' (R2=0.432, p=0.002). CONCLUSION: A higher plasma BNP at baseline in AF patients may help to predict the failure to maintain sinus rhythm 4 weeks after electrical cardioversion, but not the early recurrence at 1 week.
Atrial Fibrillation ; Body Mass Index ; Electric Countershock ; Heart Failure ; Humans ; Multivariate Analysis ; Natriuretic Peptide, Brain ; Plasma ; Prospective Studies ; Recurrence

BACKGROUND: Cardiovascular complications are major causes of morbidity and mortality following non-cardiac thoracic operations. Recent studies have demonstrated that elevation of N-Terminal Pro-B-type natriuretic peptide (NT-proBNP) levels can predict cardiac complications following non-cardiac major surgery as well as cardiac surgery. However, there is little information on the correlation between lung resection surgery and NT-proBNP levels. We evaluated the role of NT-proBNP as a potential marker for the risk stratification of cardiac complications following lung resection surgery. MATERIAL AND METHODS: Prospectively collected data of 98 patients, who underwent elective lung resection from August 2007 to February 2008, were analyzed. Postoperative adverse cardiac events were categorized as myocardial injury, ECG evidence of ischemia or arrhythmia, heart failure, or cardiac death. RESULTS: Postoperative cardiac complications were documented in 9 patients (9/98, 9.2%): Atrial fibrillation in 3, ECG-evidenced ischemia in 2 and heart failure in 4. Preoperative median NT-proBNP levels was significantly higher in patients who developed postoperative cardiac complications than in the rest (200.2 ng/L versus 45.0 ng/L, p=0.009). NT-proBNP levels predicted adverse cardiac events with an area under the receiver operating characteristic curve of 0.76 [95% confidence interval (CI) 0.545~0.988, p=0.01]. A preoperative NT-proBNP value of 160 ng/L was found to be the best cut-off value for detecting postoperative cardiac complication with a positive predictive value of 0.857 and a negative predictive value of 0.978. Other factors related to cardiac complications by univariate analysis were a higher American Society of Anesthesiologists grade, a higher NYHA functional class and a history of hypertension. In multivariate analysis, however, high preoperative NT-proBNP level (>160 ng/L) only remained significant. CONCLUSION: An elevated preoperative NT-proBNP level is identified as an independent predictor of cardiac complications following lung resection surgery.
Arrhythmias, Cardiac ; Atrial Fibrillation ; Electrocardiography ; Heart Failure ; Humans ; Hypertension ; Ischemia ; Lung ; Multivariate Analysis ; Natriuretic Peptide, Brain ; Peptide Fragments ; Prognosis ; Prospective Studies ; ROC Curve ; Thoracic Surgery

BACKGROUND AND OBJECTIVES: Acute heart failure (AHF) is associated with a poor prognosis and it requires repeated hospitalizations. However, there are few studies on the characteristics, treatment and prognostic factors of AHF. The aims of this study were to describe the clinical characteristics, management and outcomes of the patients hospitalized for AHF in Korea. SUBJECTS AND METHODS: We analyzed the clinical data of 3,200 hospitalization episodes that were recorded between June 2004 and April 2009 from the Korean Heart Failure (KorHF) Registry database. The mean age was 67.6+/-14.3 years and 50% of the patients were female. RESULTS: Twenty-nine point six percent (29.6%) of the patients had a history of previous HF and 52.3% of the patients had ischemic heart disease. Left ventricular ejection fraction (LVEF) was reported for 89% of the patients. The mean LVEF was 38.5+/-15.7% and 26.1% of the patients had preserved systolic function (LVEF > or =50%), which was more prevalent in the females (34.0% vs. 18.4%, respectively, p<0.001). At discharge, 58.6% of the patients received beta-blockers (BB), 53.7% received either angiotensin converting enzyme-inhibitors or angiotensin receptor blockers (ACEi/ARB), and 58.4% received both BB and ACEi/ARB. The 1-, 2-, 3- and 4-year mortality rates were 15%, 21%, 26% and 30%, respectively. Multivariate analysis revealed that advanced age {hazard ratio: 1.023 (95% confidence interval: 1.004-1.042); p=0.020}, a previous history of heart failure {1.735 (1.150-2.618); p=0.009}, anemia {1.973 (1.271-3.063); p=0.002}, hyponatremia {1.861 (1.184-2.926); p=0.007}, a high level of serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) {3.152 (1.450-6.849); p=0.004} and the use of BB at discharge {0.599 (0.360-0.997); p=0.490} were significantly associated with total death. CONCLUSION: We present here the characteristics and prognosis of an unselected population of AHF patients in Korea. The long-term mortality rate was comparable to that reported in other countries. The independent clinical risk factors included age, a previous history of heart failure, anemia, hyponatremia, a high NT-proBNP level and taking BB at discharge.
Anemia ; Angiotensin Receptor Antagonists ; Angiotensins ; Female ; Heart ; Heart Failure ; Hospitalization ; Humans ; Hyponatremia ; Korea ; Multivariate Analysis ; Myocardial Ischemia ; Natriuretic Peptide, Brain ; Peptide Fragments ; Prognosis ; Registries ; Risk Factors ; Stroke Volume

OBJECTIVE: Post-contrast T1 values are closely related to the degree of myocardial extracellular space expansion. We determined the relationship between post-contrast T1 values and left ventricular (LV) diastolic function, LV remodeling, and neurohormonal activation in patients with dilated cardiomyopathy (DCM). MATERIALS AND METHODS: Fifty-nine patients with DCM (mean age, 55 +/- 15 years; 41 males and 18 females) who underwent both 1.5T magnetic resonance imaging and echocardiography were enrolled. The post-contrast 10-minute T1 value was generated from inversion time scout images obtained using the Look-Locker inversion recovery sequence and a curve-fitting algorithm. The T1 sample volume was obtained from three interventricular septal points, and the mean T1 value was used for analysis. The N-Terminal pro-B-type natriuretic peptide (NT-proBNP) level was measured in 40 patients. RESULTS: The mean LV ejection fraction was 24 +/- 9% and the post-T1 value was 254.5 +/- 46.4 ms. The post-contrast T1 value was significantly correlated with systolic longitudinal septal velocity (s'), peak late diastolic velocity of the mitral annulus (a'), the diastolic elastance index (Ed, [E/e']/stroke volume), LV mass/volume ratio, LV end-diastolic wall stress, and LV end-systolic wall stress. In a multivariate analysis without NT-proBNP, T1 values were independently correlated with Ed (beta = -0.351, p = 0.016) and the LV mass/volume ratio (beta = 0.495, p = 0.001). When NT-proBNP was used in the analysis, NT-proBNP was independently correlated with the T1 values (beta = -0.339, p = 0.017). CONCLUSION: Post-contrast T1 is closely related to LV remodeling, diastolic function, and neurohormonal activation in patients with DCM.
Adult ; Aged ; Algorithms ; Blood Pressure ; Cardiomyopathy, Dilated/*diagnosis/radiography ; Echocardiography ; Extracellular Space/physiology/*radiography ; Female ; Heart Ventricles/physiopathology/radiography ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Multivariate Analysis ; Natriuretic Peptide, Brain/analysis ; Peptide Fragments/analysis ; *Ventricular Remodeling

BACKGROUND: The aim of this study was to evaluate the value of preoperative plasma B-type natriuretic peptide (BNP) level in predicting postoperative in-hospital major adverse cardiac events (MACE, defined as atrial fibrillation, congestive heart failure, nonfatal myocardial infarction and cardiac death) in elderly patients undergoing orthopedic surgery. METHODS: Between March 2010 and September 2011, data from 156 patients (aged 65 years or older) who underwent scheduled or emergent orthopedic surgery, were investigated. Screening for postoperative in-hospital MACE was performed using clinical criteria. RESULTS: MACE occurred in 12 patients (7.7%). The BNP level was significantly higher in patients with MACE than in those without (median, 152.0; interquartile range [36.3 to 352.8] pg/mL vs. median, 36.8; interquartile range [15.5 to 98.1] pg/mL, p=0.005). The BNP level was positively correlated with the revised cardiac risk index score (r=0.300, p=0.001). In a receiver operating characteristic (ROC) analysis for MACE, the ROC for BNP was 0.746 (95% confidence interval, 0.602 to 0.891). At the optimal cut-off point (BNP=110 pg/mL), the sensitivity, specificity and positive and negative predictive values were 66.7, 81.2, 22.0% and 96.6%, respectively. On multivariate analysis, preoperative BNP was an independent predictor for MACE (odds ratio, 5.091; p=0.018) after adjusting for baseline confounding factors such as diabetes mellitus and history of cerebrovascular accident. CONCLUSION: The preoperative BNP level may be a useful tool in stratifying the risk for MACE in elderly patients undergoing orthopedic surgery.
Aged ; Atrial Fibrillation ; Diabetes Mellitus ; Heart Failure ; Humans ; Mass Screening ; Multivariate Analysis ; Myocardial Infarction ; Natriuretic Peptide, Brain ; Orthopedics ; Plasma ; ROC Curve ; Sensitivity and Specificity

BACKGROUNDRadiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) has developed rapidly, and is a commonly performed ablation in many major hospitals throughout the world, due to its satisfactory results. The aim of this study was to detect the effect of RFCA on C-reactive protein (CRP), brain natriuretic peptide (BNP), and echocardiograph in patients with persistent and permanent AF.

METHODSA total of 120 patients (71 males, mean age (50.8 ± 12.0) years) with persistent and permanent AF undergoing RFCA under guidance of the Carto merge technique were studied. Left atrial diameter (LAD), right atrial diameter (RAD), left ventricular ejection fraction (LVEF), CRP, and BNP were observed 3, 6 and 12 months after RFCA and compared with results before RFCA. The recurrence of atrial arrhythmias was observed 3 and 12 months after the procedure.

RESULTSCompared with that before RFCA, LAD and RAD decreased and LVEF increased significantly after RFCA. Meanwhile, the levels of CRP and BNP were reduced significantly at 3, 6, and 12 months after RFCA (P < 0.05). In the non-recurrent patients, LVEF was increased significantly compared with the recurrent patients at 3, 6, and 12 months after RFCA (P < 0.05). CRP and BNP levels were decreased significantly in the non-recurrent patients compared with the recurrent patients at 3, 6, and 12 months after RFCA (P < 0.05). After one or two applications of RFCA, during a follow-up of 12 months, 12 patients (10.0%) had AF, 10 patients (8.3%) had atrial flutter, and 5 patients had atrial tachycardia (4.2%).

CONCLUSIONSConversion of AF to sinus rhythm by RFCA, has been shown to reduce LA size and improve LVEF. It can also significantly decrease the levels of CRP and BNP in patients with persistent and permanent AF and reduce the risk of inflammation and developing heart failure.

Atrial Fibrillation ; blood ; diagnostic imaging ; surgery ; C-Reactive Protein ; analysis ; Catheter Ablation ; Echocardiography ; Female ; Humans ; Male ; Middle Aged ; Natriuretic Peptide, Brain ; blood