Using SERS-based microfluidic paper-based device (µPAD) for calibration-free quantitative measurement of AMI cardiac biomarkers.

Recently, surface enhanced Raman scattering (SERS) has attracted much attention in medical diagnosis applications owing to better detection sensitivity and lower limit of detection (LOD) than colorimetric detection. In this paper, a novel calibration-free SERS-based µPAD with multi-reaction zones for simultaneous quantitative detection of multiple cardiac biomarkers - GPBB, CK-MB and cTnT for early diagnosis and prognosis of acute myocardial infarction (AMI) are presented. Three distinct Raman probes were synthesised, subsequently conjugated with respective detecting antibodies and used as SERS nanotags for cardiac biomarker detection. Using a conventional calibration curve, quantitative simultaneous measurement of multiple cardiac biomarkers on SERS-based µPAD was performed based on the characteristic Raman spectral features of each reporter used in different nanotags. However, a calibration free point-of-care testing device is required for fast screening to rule-in and rule-out AMI patients. Partial least squares predictive models were developed and incorporated into the immunosensing system, to accurately quantify the three unknown cardiac biomarkers levels in serum based on the previously obtained Raman spectral data. This method allows absolute quantitative measurement when conventional calibration curve fails to provide accurate estimation of cardiac biomarkers, especially at low and high concentration ranges. Under an optimised condition, the LOD of our SERS-based µPAD was identified at 8, 10, and 1 pg mL-1, for GPBB, CK-MB and cTnT, respectively, which is well below the clinical cutoff values. Therefore, this proof-of-concept technique shows significant potential for highly sensitive quantitative detection of multiplex cardiac biomarkers in human serum to expedite medical decisions for enhanced patient care.

Markers of maternal cardiac dysfunction in pre-eclampsia and superimposed pre-eclampsia.

AUTHORS: Frances Conti-Ramsden MBBS Academic Clinical Fellow1, Carolyn Gill PhD BRC Research Assistant1, Paul T Seed MSc CStat Senior Lecturer in Medical Statistics1, Kate Bramham PhD Clinical Senior Lecturer in Nephrology2, Lucy C Chappell PhD NIHR Research Professor in Obstetrics1, Fergus P McCarthy PhD Clinical Senior Lecturer in Obstetrics and Gynaecology1,3. OBJECTIVES: To determine whether glycogen phosphorylase isoenzyme B (GPBB) and/or brain natriuretic peptide (BNP) concentrations are elevated in pre-eclampsia and superimposed pre-eclampsia (SPE), demonstrating cardiac ischaemia and strain. STUDY DESIGN: A nested case-control study was performed using samples and clinical data available from a prospective pregnancy cohort. Four groups were selected: healthy pregnant controls (n = 21), pre-eclampsia (n = 19), pre-existing chronic hypertension (CHT) and/or chronic kidney disease (CKD) without (n = 20) or with superimposed pre-eclampsia (SPE) (n = 19). Plasma samples were taken at time of disease or the third trimester in controls. MAIN OUTCOME MEASURES: Plasma concentrations of GPBB and BNP. RESULTS: There was no significant difference in GPBB plasma concentrations between controls and pre-eclampsia (geometric mean (GM) [95% CI]: 4.74 [2.54-8.84]ng/mL vs 5.01 [2.58-9.74]ng/mL, p = 0.90)), or between CHT and/or CKD and SPE (GM [95% CI]: 9.49 [4.93-18.25]ng/mL vs 10.24 [5.27-19.92]ng/mL, p = 0.87). BNP plasma concentrations were significantly raised in women with pre-eclampsia compared to controls (GM [95% CI]: 31.83 [20.18-50.22]pg/mL vs 11.33 [7.34-17.51]pg/mL, p = 0.001). Women with CKD, but not CHT, who developed SPE had elevated BNP concentrations. There were no significant differences in BNP concentration between women with comorbidity (CHT and/or CKD) and controls. CONCLUSIONS: GPBB has a limited role as a biomarker in hypertensive disorders of pregnancy. BNP concentrations were elevated in pre-eclampsia compared to controls. This suggests cardiac strain at the time of pre-eclampsia. Further studies are needed to examine whether BNP can identify women at increased risk of cardiovascular disease.

New biomarker for acute ischaemic stroke: plasma glycogen phosphorylase isoenzyme BB.

BACKGROUND: Glycogen phosphorylase is the key enzyme that breaks down glycogen to yield glucose-1-phosphate in order to restore depleted energy stores during cerebral ischaemia. We sought to determine whether plasma levels of glycogen phosphorylase BB (GPBB) isoform increased in patients with acute ischaemic stroke (AIS). METHODS: We studied plasma GPBB levels within 12 hours and again at 48±24 hours of symptom onset in 172 patients with imaging-confirmed AIS and 133 stroke-free individuals. We determined the ability of plasma GPBB to discriminate between cases and controls and examined the predictive value of plasma GPBB for 90-day functional outcome, 90-day survival and acute lesion volumes on neuroimaging. RESULTS: The mean (SD) GPBB levels were higher in cases (46.3±38.6 ng/mL at first measurement and 38.6±36.5 ng/mL at second measurement) than in controls (4.1±7.6 ng/mL, p<0.01 for both). The area under the receiver operating characteristic (ROC) curve for case-control discrimination based on first GPBB measurement was 0.96 (95% CI 0.93 to 0.98). The sensitivity and specificity based on optimal operating point on the ROC curve (7.0 ng/mL) were both 93%. GPBB levels increased in 90% of patients with punctate infarcts (<1.5 mL) and in all patients admitted within the first 4.5 hours of onset. There was no correlation between GPBB concentration and either clinical outcome or acute infarct volume. CONCLUSION: GPBB demonstrates robust response to acute ischaemia and high sensitivity for small infarcts. If confirmed in more diverse populations that also include stroke mimics, GPBB could find utility as a stand-alone marker for acute brain ischaemia.

Troponins, heat shock proteins and glycogen phosphorylase BB in umbilical cord blood of complicated pregnancies.

PURPOSE OF THE STUDY: Heat shock proteins (Hsp) are evolutionary conserved molecules with a chaperone role in cell survival. We hypothesized that cord blood concentrations of molecules reflecting fetal cardiac muscle insult, including Hsp, troponins cTnI and cTnT, and glycol-phosphorylase BB (GP-BB) would be elevated in pregnancies complicated by gestational diabetes (GDM) or preeclampsia (PIH) compared to healthy controls. MATERIALS AND METHODS: Pregnant women admitted for delivery at >28 weeks were divided into four groups: healthy patients delivered vaginally (VAG), healthy patients delivered by c-section (CS), patients with PIH, and patients with GDM. Demographics, clinical characteristics, and cord blood concentrations of Hsp, troponins cTnI and cTnT, and GP-BB were compared between groups. Statistical analyses included t-test, Chi square, and Wilcoxon rank sum as appropriate. RESULTS: cTnI concentrations were significantly higher in the PIH group compared to the GDM and VAG groups and they were higher in the CS group compared to the VAG group. Concentrations of Hsp70 were higher in the GDM group compared to the VAG and CS groups. Concentration of GP-BB was higher in the PIH group compared to the VAG group. CONCLUSIONS: GP-BB and cTNI are the most sensitive markers for PIH-related fetal myocyte injury as is Hsp70 in pregnancies complicated by GDM.

Altered Maternal Plasma Glycogen Phosphorylase Isoenzyme BB as a Biomarker for Preeclampsia and Small for Gestational Age.

OBJECTIVES: To investigate whether maternal plasma glycogen phosphorylase BB (GPBB) levels were altered in early pregnancy and/or at the time of diagnosis of disease in preeclampsia (term and preterm <37 weeks' gestation) or small for gestational age (SGA). METHODS: We conducted 6 nested case-control studies within the Screening of Pregnancy Endpoint (SCOPE) Ireland cohort. Blood samples from women with preeclampsia or SGA were analyzed both from the time of disease presentation and at 15 and 20 weeks' gestation. These were compared with control samples obtained from SCOPE women with healthy uncomplicated pregnancies matched for age, ethnicity, parity, body mass index, and gestational age. Glycogen phosphorylase BB levels were measured using the Diacordon GPBB enzyme-linked immunosorbent assay (Diagenics, Germany). RESULTS: Glycogen phosphorylase BB levels were higher in women with preeclampsia compared with controls at the time of disease (term preeclampsia median [interquartile range (IQR)]: 22.2 [15.1-39.8] ng/mL vs 16.9 [10.4-19.1] ng/mL; P = .04; N = 14 and preterm preeclampsia median [IQR]: 23.1 [11.2-30.9] ng/mL vs 17.2 [9.8-19.1] ng/mL; P = .04; N = 11) and at 20 weeks' gestation (median [IQR]: 23.0 [15.6-31.4] ng/mL vs 17.0 [13.4-23.6] ng/mL; N = 39; P = .04). Glycogen phosphorylase BB levels were also significantly higher in women with SGA compared with normal controls at the time of disease detection (median [IQR]: 22.7 [12.6-25.5] ng/mL vs 17.0 [9.8-18.0] ng/mL; N = 23; P = .03) but significantly less than controls at 15 weeks' gestation prior to disease detection (median [IQR]: 16.0 [12.1-23.2] ng/mL vs 22.2 [17.0-28.9] ng/mL; N = 25; P = .02). CONCLUSION: Glycogen phosphorylase BB alone has modest predictive abilities for the development of preeclampsia or SGA. Further research may examine its use in combination with other markers.

Glycogen phosphorylase BB levels are associated with haemodynamic parameters in cirrhotic patients undergoing transjugular intrahepatic portosystemic shunt insertion.

BACKGROUND: Transjugular intrahepatic portosystemic shunts (TIPS) have become a widely accepted tool in the treatment of patients with symptomatic portal hypertension. The aim of our study was to assess glycogen phosphorylase BB (GPBB) concentration in relation to echocardiographic and haemodynamic parameters in patients before and after TIPS insertion. METHODS: The study population consisted of 55 patients (38 men and 17 women, age 55.6±8.9 years, range 37-74 years) with liver cirrhosis treated with transjugular portosystemic shunting. GPBB, echocardiographic, and haemodynamic parameters were measured before TIPS insertion and 24 h after the procedure. GPBB concentrations were assessed using the Cardiac Array for Evidence Investigator protein biochip. Correlation between parameters was assessed using the Spearman's coefficient. RESULTS: Serum post-procedural GPBB concentrations were increased in comparison with baseline (5.58 vs. 2.67 µg/L, P<0.001). GPBB concentration after TIPS significantly correlated with baseline systemic vascular resistence (r=0.330; P=0.017) and cardiac index (r=0.313; P=0.025). CONCLUSION: GPBB concentration measurement may be a useful tool for monitoring myocardial ischemia during a TIPS procedure.

Glycogen phosphorylase isoenzyme BB, creatine kinase isoenzyme MB and troponin I for monitoring patients with percutaneous coronary intervention - a pilot study.

AIM: The glycogen phosphorylase isoenzyme BB (GPBB), as an ischemic marker, has not yet been investigated after elective percutaneous coronary intervention (PCI). ose aim of the study was to monitor GPBB, creatine kinase myocardial isoform (CK-MB) mass) and troponin I (TnI) value after PCI in correlation with ischemic incidents. METHODS: Forty-two consecutive patients undergoing elective PCI were included in the study. Baseline blood samples and two more after the PCI (3 and 24 hours) were taken. The significance of cardiac markers in twenty-ththe stable patients with baseline values of CK-MB mass and TnI below the upper reference limit (URL) was evaluated based on ischemic incidents after PCI. RESULTS: TnI value was the only biomarker that was statistically significant at 3 and 24 hours after PCI in group of 23 stable patients. An overall comparisonthe biomarkers of 18 patients without and five patients with ischemic incidents displayed significant differences only for the baseline GPBB (p=0.019) and CK-MB mass 24 hours after PCI (p=0.034). Ischemic incidents were independently predictable only based on overall CK-MB mass measurements (OR=1.680, p=0.041) and particularly GPBB at baseline (OR=1.899, p=0.008) and CK-MB mass 24 hours after PCI (OR=2.111, p=0.022). CONCLUSIONS: Only significant increases in TnI were observed after elective PCI with ischemic incidents predicted using GPBB and CK-MB mass measurements.

Glycogen phosphorylase BB as a potential marker of cardiac toxicity in patients treated with anthracyclines for acute leukemia.

OBJECTIVES: The aim of the presented study was to assess plasma glycogen phosphorylase BB (GPBB) concentrations in acute leukemia patients treated with anthracycline containing chemotherapy. BACKGROUND: Anthracyclines represent the highest risk for development of cardiotoxicity. GPBB belongs to proposed biomarkers of cardiac injury with a very limited experience in this context. METHODS: Totally, 24 adult patients with acute leukemia were enrolled. Plasma GPBB concentrations were measured by ELISA at diagnosis (before chemotherapy), after first chemotherapy with anthracyclines and 6 months after the completion of treatment. The cut-off value for GPBB positivity was 10.00 µg/L as recommended by the manufacturer. RESULTS: Before chemotherapy, the mean plasma GPBB concentration was 5.25±3.81 µg/L, increased above the cut-off in 1 patient (4.2 %). After the first chemotherapy, the mean GPBB was 6.61±5.54 µg/L, positive in 7 (29.2 %) patients. Six months after treatment, the mean GPBB was 10.06±11.41 µg/L, positive in 8 (33.3 %) patients. Six months after treatment, we found a significant correlation between elevation in GPBB and diastolic left ventricular dysfunction on echocardiography (r=0.621; p<0.0001). The differences in plasma GPBB between healthy blood donors and patients treated for acute leukemia were statistically significant (p<0.01 in all cases). CONCLUSION: Our results suggested that GPBB could become a potential biomarker for detection of acute and chronic cardiotoxicity associated with anthracycline containing chemotherapy. The predictive value for development of treatment-related cardiomyopathy in future is not clear and will be evaluated during the follow-up. Further studies are needed to define the potential role of GPBB and other biomarkers in the assessment of chemotherapy-induced cardiotoxicity (Ref. 21). Text in PDF www.elis.sk.

Glycogen phosphorylase isoenzyme BB plasma kinetics is not related to myocardial ischemia induced by exercise stress echo test.

BACKGROUND: Glycogen phosphorylase BB (GPBB) is released from cardiac cells during myocyte damage. Previous studies have shown contradictory results regarding the relation of enzyme release and reversible myocardial ischemia. The aim of this study was to determine the plasma kinetics of GPBB as a response to the exercise stress echocardiographic test (ESET), and to define the relationship between myocardial ischemia and enzyme plasma concentrations. METHODS: We studied 46 consecutive patients undergoing ESET, with recent coronary angiography. In all patients, a submaximal stress echo test according to Bruce protocol was performed. Concentration of GPBB was measured in peripheral blood that was sampled 5 min before and 10, 30 and 60 min after ESET. RESULTS: There was significant increase of GPBB concentration after the test (p=0.021). Significant increase was detected 30 min (34.9% increase, p=0.021) and 60 min (34.5% increase, p=0.016) after ESET. There was no significant effect of myocardial ischemia on GPBB concentrations (p=0.126), and no significant interaction between sampling intervals and myocardial ischemia, suggesting a similar release profile of GPBB in ischemic and non-ischemic conditions (p=0.558). Patients in whom ESET was terminated later (stages 4 or 5 of standard Bruce protocol; n=13) had higher GPBB concentrations than patients who terminated ESET earlier (stages 1, 2 or 3; n=33) (p=0.049). Baseline GPBB concentration was not correlated to any of the patients' demographic, clinical and hemodynamic characteristics. CONCLUSIONS: GPBB plasma concentration increases after ESET, and it is not related to inducible myocardial ischemia. However, it seems that GPBB release during ESET might be related to exercise load/duration.

Glycogen phosphorylase isoenzyme BB plasma concentration is elevated in pregnancy and preterm preeclampsia.

Glycogen phosphorylase is a key enzyme in glycogenolysis. Released with myocardial ischemia, blood concentration of glycogen phosphorylase isoenzyme BB (GPBB) is a marker of acute coronary syndromes. Pregnancy imposes metabolic stress, and preeclampsia is associated with cardiac complications. However, plasma GPBB concentration during pregnancy is unknown. This study was conducted to determine maternal plasma GPBB concentration in normal pregnancy and in preeclampsia. Plasma samples from 6 groups (n=396) were studied: nonpregnant and pregnant women with normal term delivery, term and preterm preeclampsia, and term and preterm small-for-gestational-age neonates. GPBB concentration was measured with a specific immunoassay. Placental tissues (n=45) obtained from pregnant women with preterm and term preeclampsia, spontaneous preterm delivery, and normal term delivery were analyzed for potential GPBB expression by immunoblotting. Median plasma GPBB concentration was higher in pregnant women than in nonpregnant women (38.7 versus 9.2 ng/mL; P<0.001), which remained significant after adjusting for age, race, and parity. Maternal plasma GPBB concentrations did not change throughout gestation. Cases of preterm (but not term) preeclampsia had higher median plasma GPBB concentrations than gestational age-matched normal pregnancy cases (72.6 versus 26.0 ng/mL; P=0.001). Small-for-gestational-age neonates did not affect plasma GPBB concentration. GPBB was detected in the placenta and was less abundant in preterm preeclampsia than in preterm delivery cases (P<0.01). There is physiological elevation of plasma GPBB concentration during pregnancy; an increase in maternal plasma GPBB is a novel phenotype of preterm preeclampsia. It is strongly suggested that these changes are attributed to GPBB of placental origin.

The diagnostic and prognostic value of first hour glycogen phosphorylase isoenzyme BB level in acute coronary syndrome.

BACKGROUND: Evaluating patients with symptoms suggestive of acute coronary syndrome (ACS) is a time consuming, expensive and problematic process in the emergency department. This study aimed to evaluate the diagnostic and prognostic value of glycogen phosphorylase isoenzyme-BB (GP-BB) in ACS. METHODS: A total of 72 patients (mean age 61.8 ± 11.6 years) with ACS were enrolled. The ELISA method for determining GP-BB level was performed and considered positive at 〉 10 ng/mL. Duration of angina, type of ACS, demographic features, myoglobin, creatinine kinase and troponin T (cTnT) were also assessed. The cTnT levels eight hours after pain onset was considered the gold standard test for the diagnosis of myocardial infarction. RESULTS: The most sensitive biomarker at first hour of admission was GP-BB (95.8%). However, the specificity of GP-BB was low (43.7%). Receiver operating characteristics curve analysis of the GP-BB level for predicting myocardial infarction revealed the area under the curve value as 0.82 (SE 0.04; 95% CI 0.78-0.85). Positive treadmill exercise test (60% vs 17%, p = 0.047), coronary artery disease (CAD; 59% vs 19%, p = 0.007), percutaneous coronary intervention (44% vs 27%, p = 0.031) and 30-day mortality and/or readmission (33% vs 5%, p = 0.028) were found to be higher in unstable angina (UA) patients having GP-BB (+). CONCLUSIONS: GP-BB is considerably cardiosensitive at the first hour of admission in patients with ACS, but the specificity of GP-BB is lower and it is elevated in nearly half of the patients with UA. However, in this group, GP-BB predicts significant CAD and the combined end-point of mortality and re-hospitalization.

Performance of glycogen phosphorylase isoenzyme BB is weak in the detection of patients with non-ST-elevation acute coronary syndrome.

OBJECTIVE: To examine the diagnostic performance of glycogen-phosphorylase-isoenzyme-BB (GPBB) combined with cardiac troponin I (cTnI) in acute coronary syndrome (ACS). DESIGN AND METHODS: Sixty patients with chest pain were investigated; GPBB and cTnI were measured. RESULTS: ACS was confirmed in 31 patients; cTnI was >0.07 µg/L in 15 patients and GPBB was >10 µg/L in 6 patients. Areas under ROC curves were similar: 0.854 (cTnI+GPBB) vs. 0.843 (cTnI), p=0.728. CONCLUSION: Combination of GPBB with cTnI does not improve the detection of ACS.

A unique case series of novel biomarkers of cardiac damage in cyclists completing the 4800 km Race Across America (RAAM).

Prolonged strenuous exercise is associated with the appearance of biomarkers of cardiac cell damage and a decline in cardiac function during recovery. Few studies have assessed repeated bouts of prolonged exercise and whether this results in further biomarker accumulation and greater dysfunction. Further, it may be useful to describe the changes in a range of biomarkers that may provide additional insight into the clinical significance of cardiac biomarker release. Four highly trained cyclists completed the 4800 km Race Across America (RAAM) in 7 days. Venous blood samples and echocardiograms were taken prior to, every 24 hours during and immediately after the RAAM. Venous blood was analysed for cardiac troponin I (cTnI), creatine kinase MB (CK-MB), fatty acid binding protein (HFABP), glycogen phosphorylase BB (GPBB) and N-Terminal Brain Natriuretic Peptide (NTproBNP). Echocardiograms allowed analysis of septal, left ventricular free wall and right ventricular free wall tissue velocities during systole and diastole. Before the RAAM cTnI levels were below the assay detection level (0.02 ng.ml⁻¹). In three riders cTnI peaked on day one (0.03 ng.ml⁻¹) and returned below detection levels post race. In the 4th rider cTnI peaked on day 5 (0.08 ng.ml⁻¹) and was still elevated post-race. Both CK-MB and H-FABP were increased during the RAAM in all 4 cyclists. In three riders H-FABP peaked on day one (3.49 to 5.09 ng.ml⁻¹) and declined over the rest of the RAAM. In the final rider H-FABP peaked on day two (5.90 ng.ml⁻¹) and then dropped back to baseline by the post-RAAM assessment. Interestingly, changes in H-FABP mirrored, temporally, changes in CK-MB in places and this may reflect an association with skeletal muscle damage. Data for GPBB value to (2.9 - 149.6 ng.ml⁻¹) and NTproBNP value to (27.3 - 310.0 ng.L⁻¹) were variable but again was elevated in all riders during the course of the RAAM. Changes in ventricular wall tissue velocities were minor and not cumulative. Peak atrial diastolic tissue velocity in the left ventricular free wall increased (P < 0.05) from 11 to 18 cm.s⁻¹ over the last two race days but this did not significantly impact the ratio of early to late diastolic wall motion. Cardiac biomarkers were elevated during the completion of the RAAM in all 4 cyclist but changes were not cumulative which suggest that the hearts of the cyclists coped well with the extreme cardiac work demanded by this ultra-endurance exercise challenge.

Direct comparison of the diagnostic value of point-of-care tests detecting heart-type fatty acid binding protein or glycogen phosphorylase isoenzyme BB in patients with acute coronary syndromes with persistent ST-segment elevation.

BACKGROUND: Myocardial infarction (MI) with its complications is one of the most serious challenges in contemporary cardiology. Among biochemical markers of myocardial necrosis, heart-type specific fatty acid binding protein (h-FABP) showed excellent sensitivity and specificity for the early diagnosis of an acute MI. The h-FABP is released rapidly (after 30 min) from the cardiomiocyte to the circulation in response to myocardial injury and may be useful for rapid confirmation or exclusion of MI. In recent years, glycogen phosphorylase BB (GP-BB) also emerged as a promising early specific marker of myocardial necrosis. Rapid, qualitative "point of care" tests (POCT) detecting h-FABP (Cardio Detect med) and GP-BB (Diacordon) have recently become available. AIM: To evaluate and compare qualitative POCTs detecting h-FABP and GP-BB in patients with an acute coronary syndrome (ACS). METHODS: We studied 52 patients with a strong suspicion of ACS with persistent ST-segment elevation and chest pain lasting less than 6 hours. The ultimate diagnosis of ST-segment elevation MI (STEMI) was confirmed in case of a second (6 h after admission) positive quantitative result of a cardiac troponin T (cTnT) test. On admission, POCTs to detect both h-FABP and GP-BB were performed. The study population was divided into two groups, with chest pain lasting 〈 3 h (n = 20) or 4-6 h (n = 32). All patients underwent coronary angiography and angioplasty if indicated. The sensitivity of the analysed biomarkers of myocardial necrosis was calculated. RESULTS: The sensitivity of h-FABP (84%) was superior in comparison to the other biomarkers, GP-BB and cTnT, which had sensitivity of 64% and 50%, respectively. Comparison of typical parameters of the diagnostic value of a test (sensitivity, predictive values and accuracy) in both time periods demonstrated that h-FABP was superior to GP-BB. In particular, sensitivity and accuracy of h-FABP was excellent in the group of patients with chest pain lasting 〈 3 h, with sensitivity of 79% for h-FABP and only 47% for GP-BB. Sensitivity and accuracy of cTnT were significantly lower (32% and 35%, respectively). CONCLUSIONS: The h-FABP seems to be an excellent early biomarker of cardiac necrosis in the group of patients with chest pain lasting 〈 3 h. The GP-BB can be also used as a biomarker of myocardic necrosis, but its sensitivity in the early phase of MI is limited.

Arginine rich coconut kernel protein modulates diabetes in alloxan treated rats.

Diabetes mellitus is a syndrome characterized by the loss of glucose homeostasis due to several reasons. In spite of the presence of known anti-diabetic medicines in the pharmaceutical market, remedies from natural resources are used with success to treat this disease. The present study was undertaken to investigate the effect of coconut kernel protein (CKP) on alloxan induced diabetes in Sprague-Dawley rats. Diabetes was induced by injecting a single dose of alloxan (150mg/kg body weight) intraperitoneally. After inducing diabetes, purified CKP isolated from dried coconut kernel was administered to rats along with a semi synthetic diet for 45 days. After the experimental period, serum glucose, insulin, activities of different key enzymes involved in glucose metabolism, liver glycogen levels and the histopathology of the pancreas were evaluated. The amount of individual amino acids of CKP was also determined using HPLC. Results showed that CKP has significant amount of arginine. CKP feeding attenuated the increase in the glucose and insulin levels in diabetic rats. Glycogen levels in the liver and the activities of carbohydrate metabolizing enzymes in the serum of treated diabetic rats were reverted back to the normal levels compared to that of control. Histopathology revealed that CKP feeding reduced the diabetes related pancreatic damage in treated rats compared to the control. These results clearly demonstrated the potent anti-diabetic activity of CKP which may be probably due to its effect on pancreatic ß cell regeneration through arginine.

The use of cardiac biomarkers in detection of cardiotoxicity associated with conventional and high-dose chemotherapy for acute leukemia.

AIM: Monitoring of cardiotoxicity of conventional and high-dose chemotherapy (HD-CT) with multiple biomarkers of cardiac injury - glycogen phosphorylase BB (GPBB), heart-type fatty acid binding protein (H-FABP), cardiac troponins (cTnT, cTnI), creatine kinase MB (CK-MB mass), myoglobin. METHODS: A total of 47 adult acute leukemia patients were studied - 24 patients treated with conventional CT containing anthracyclines (ANT) and 23 patients treated with HD-CT (myeloablative preparative regimen) followed by hematopoietic cell transplantation (HCT). Cardiac biomarkers were assessed prior to treatment (before CT/HD-CT), after first CT with ANT, after last CT with ANT in the first group, after HD-CT and after HCT in the second group. Values above the reference range were considered elevated. RESULTS: Before CT/HD-CT, all biomarkers of cardiac injury were below the cut-offs in all patients. GPBB increased above the cut-off (7.30 microg/L) in 4 (16.7%) patients after first CT and in 5 (20.8%) patients after last CT with ANT. GPBB increased above the cut-off in 5 (21.7%) patients after HD-CT and remained elevated in 5 (21.7%) patients after HCT. CTnI became elevated (above 0.40 microg/L) in 2 (8.3%) patients after first and last CT with ANT. Both patients with cTnI positivity had elevated GPBB. Other tested biomarkers remained below the cut-offs during the study. CONCLUSION: Our results suggest that GPBB could become a sensitive biomarker for detection of acute cardiotoxicity associated with conventional CT containing ANT and HD-CT followed by HCT. The predictive value for development of cardiomyopathy in the future is not known and should be evaluated during a prospective follow-up. Based on our data, a larger prospective and multicenter study would be most desirable to define the potential role of new circulating biomarkers in the assessment of cardiotoxicity in oncology.

A timely diagnosis of myocardial infarction.

The diagnosis of acute myocardial infarction currently rests on the measurement of troponin, a biomarker of myocardial necrosis. Unfortunately, the current generation troponin assays detect troponin only 6-9 h after symptom onset. This can lead to a delay in diagnosis and also excessive resource utilization when triaging patients who, ultimately, have noncardiac causes of acute chest pain. For these reasons, there has been extensive research interest in biomarkers that can detect and rule out myocardial infarction early after symptom onset. These include markers of myocardial injury, such as myoglobin, heart-type fatty acid binding protein, glycogen phosphorylase BB; hemostatic markers, such as D-dimer; and finally, inflammatory markers, such as matrix metalloproteinase 9. Recently, highly sensitive troponin assays have reported an early sensitivity for myocardial infarction of greater than 95%, although at a cost of reduced specificity. The optimal strategy with which to use these novel biomarkers and highly sensitive troponins has yet to be determined, and interpretation of their results in light of thorough clinical assessment remains essential.