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Martina Zaninotto

Publications and source records attributed to Martina Zaninotto.

At least 19 recordsLinked to original sources
PubMed2007

Evidence for decreased circulating apelin beyond heart involvement in uremic cardiomyopathy.

BACKGROUND: Plasma apelin concentration in heart failure has been described in small studies reporting conflicting results. In hemodialysis (HD) patients, apelin decreased more in those with more severe heart involvement. It is unclear if uremia is connected to this reduction irrespective of heart failure. We compared apelin in two cardiomyopathies with different renal function. METHODS: Observational study conducted in 30 adult Caucasian outpatients in class I NYHA not affected by diabetes or ischemic heart, 15 with idiopathic dilated cardiomyopathy (DCM) and 15 with uremic dilated cardiomyopathy undergoing HD. Plasma apelin, creatinine, high-sensitivity C-reactive protein, endothelin, NT proB-type natriuretic peptide (NT-proBNP), and Doppler echocardiogram were evaluated. RESULTS: Heart involvement was more severe in the DCM patients (lower ejection fraction, greater diastolic volume index, and worse index of myocardial performance). Median value of apelin in HD patients (19.1 pg/ml) was one third of that in DCM patients (58.2 pg/ml) whereas creatinine, NT-proBNP, and C-reactive protein were 11, 80, and 9 times higher respectively in HD than in DCM patients. Median values of endothelin were comparable in both groups. Apelin was not significantly correlated with any variable. CONCLUSION: Uremic status was the determinant for decreased plasma apelin in HD patients regardless of the severity of heart involvement.

Adult↗
PubMed2006

External Quality Assessment: an effective tool for Clinical Governance in laboratory medicine.

The implementation of Clinical Governance will require a redefinition of duties and accountability as a prerequisite to develop and achieve an overall improvement in clinical care through a culture of assessment and monitoring of quality. External Quality Assessment Schemes (EQAS) are the main tool enabling laboratories to measure the quality of their results; they must carefully assess and monitor all elements contributing to the formulation of laboratory information (results, reference ranges/decisional levels, interpretative comments and diagnostic algorithms). There are different ways to design and manage a Scheme and EQAS coordinators are mainly responsible for its effectiveness. The present paper reports, as an example, some experiences of the Centre of Biomedical Research (CRB), which manages EQAS according to high quality specifications and laboratories' needs, that can reflect the Clinical Governance philosophy. Our findings show that EQAS are able to control all the above aspects and, if organisers are committed to fulfilling the responsibility and accountability principles, they will be of great value in quality assessment and in developing an External Quality Assurance Program (EQAP). This is an inter-laboratory comparison designed and conducted to assure the following: evaluation of participants' performance (by evaluating not only analytical performance, but also test interpretation, and advice for clinicians on laboratory requests and diagnosis); evaluation of method performance; and continuous education, training and help. The main aim of the activities of an EQAP in Laboratory Medicine is to sustain improvements in the quality of services provided by participating laboratories for the benefit of patients.

Clinical Laboratory Techniques↗
PubMed2006

Innotrac Aio!: a point-of-care or a routine analyzer? Analytical performance and plasma/whole blood comparison.

BACKGROUND AND METHODS: The aim of the present study was to evaluate the analytical performance of the Innotrac Aio! analyzer in measuring the cardiac markers troponin I (TnI), myoglobin (Myo) and creatine kinase-MB (CK-MB), both in lithium heparin plasma and in whole blood. RESULTS: TnI analytical sensitivity was 0.012 microg/L and the concentration corresponding to CV=10% was 0.036 microg/L. In healthy subjects, the 99th percentile TnI values were 0.023 and 0.016 microg/L in whole blood and in plasma, respectively. One hundred samples were tested both in whole blood and in plasma: TnI-whole-blood=1.16-plasma+0.011, bias=+0.18 (95% CI from -0.22 to +0.59); Myo-whole-blood=1.04-plasma-1.93, bias=+1.08 (95% CI from -6.17 to +8.32); CK-MB-whole-blood=1.11-plasma-0.09, bias=+0.96 (95% CI from -0.53 to +2.45). The method comparison with the RxL Dimension analyzer for TnI and Myo gave the following results: TnI Aio!=0.30 TnI RxL+0.00; bias=-5.80 (95% CI from -7.81 to -3.78), Myo Aio!=1.33 Myo RxL+0.42, bias=+53.09 (95% CI from +38.44 to +67.74). CONCLUSIONS: The analytical performance of the Innotrac Aio! analyzer was satisfactory for all three cardiac markers evaluated and, in particular, the TnI method provided sensitive and accurate results. The most important finding in this study is the possibility to perform the tests as either routine or point-of-care analysis, thus overcoming the variability of results obtained employing different methods.

Biomarkers↗
PubMed2006

Analytical and clinical evaluation of a new heart-type fatty acid-binding protein automated assay.

BACKGROUND: The accurate and rapid recognition of myocardial injury in patients presenting in the emergency department (ED) with chest pain continues to be a clinical challenge. Heart-type fatty acid-binding protein (H-FABP) appears to be one of the best candidates among the new early cardiac markers studied. METHODS: We evaluated the analytical characteristics of a new quantitative and fully automated H-FABP assay (Randox Laboratories Ltd., Crumlin, UK) and compared its clinical performance with respect to the myoglobin (Myo) assay (Dade Behring, Milan, Italy). A precision study was carried out by testing three levels of quality control (QC) material and two in-house pool (P) samples. To test the accuracy of H-FABP determinations in plasma (lithium-heparin) samples, H-FABP concentrations measured in a set of matched sera and plasma samples were compared. A total of 77 non-consecutive patients (51 males and 26 females; 62+/-16 years) who presented to the ED with chest pain suggesting myocardial ischemia were enrolled. The patients were classified into two groups (acute myocardial infarction, n=22; non-acute myocardial infarction, n=55) on the basis of the discharge diagnosis. RESULTS: The between-day imprecision for three levels of control material and serum pool samples was 6.26%-8.04% (range 2.32-44.03 microg/L) and 9.03%-12.63% (range 11.85-65.13 microg/L), respectively. In the serum vs. plasma study, bias was +0.178 (95% CI -0.033 to +0.389). The best cut-off and the associated diagnostic efficacy were 95 microg/L and 89.47% for Myo and 5.09 microg/L and 98.70% for H-FABP, respectively. CONCLUSIONS: H-FABP determination in patients with ischemic symptoms may be a more reliable early indication of cardiac damage than myoglobin.

Aged↗
PubMed2005

Evaluation of a new capillary zone electrophoresis system for the identification and typing of Bence Jones Protein.

OBJECTIVES: Capillary electrophoresis has recently emerged as a new sensitive technique for the separation of urinary proteins. We evaluated a new method for Bence Jones Protein (BJP) detection and characterization on native urine samples by the Paragon CZE 2000 system. To avoid interference in electrophoretic separation, urine samples were preliminarily treated for the selective removal of interfering salt particles. DESIGN AND METHODS: The evaluation was done on a total of 350 fresh 24-h urine samples. The salt particle removal consisted of a manual chromatographic separation, optimized in the course of our evaluation. Capillary zone urinary protein electrophoresis (CZ-UPE) was compared with conventional high-resolution electrophoresis on an agarose gel, while capillary immunosubtraction (CZU-IFE) was compared with agarose gel immunofixation. RESULTS: After finding a consistent protein loss in eluates, the preanalytical treatment was optimized by changing sample dilution and eluate collection. The within- and between-run imprecision values for monoclonal peaks corresponding to BJP ranged from 0.4-12.2% to 3.3-6.3%, respectively. The detection limit for BJP, defined as the lowest measurable monoclonal peak on CZ-UPE, was 0.0012 g/L for kappa BJP and 0.0007 g/L for lambda BJP. CZ-UPE and CZU-IFE sensitivities were significantly lower in urine samples with a total protein level < or = 100 mg/L (67% and 78%, respectively) compared to those with total protein >100 mg/L (92% and 94%, respectively). Comparison between BJP measurements obtained from densitometric scanning with those from absorbance tracing showed a correlation coefficient of 0.994 and a bias of 29.8 mg/L. CONCLUSIONS: Paragon CZE 2000 can be introduced in routine for screening and typing of BJP; in urine samples with a total protein level >100 mg/L, the performance is consistent with results from published validation studies on CZE applied to serum samples.

Bence Jones Protein↗
PubMed2005

Cardiac troponin I in asphyxiated neonates.

BACKGROUND: Cardiac troponins T (cTnT) and I (cTnI) are well-established markers in detecting myocardial ischemic damage in adults. Perinatal asphyxia is associated with cardiac dysfunction. OBJECTIVES: To evaluate serum concentrations of cTnI in asphyxiated neonates and to investigate whether cTnI is correlated with the traditional markers of asphyxia. METHODS: Blood samples were collected from 13 asphyxiated neonates (umbilical artery pH<7.18 and either a 1-min Apgar score<4 or a 5-min Apgar score<7) and 39 controls. Data on gestation, birth weight, sex, Apgar scores, mode of delivery, umbilical pH, creatinine, serum activity of aspartate and alanine aminotransferase, and QTc interval were investigated. RESULTS: Median (range) cTnI concentrations were significantly higher in asphyxiated neonates with respect to healthy infants: 0.36 microg/l (0.05-11) versus 0.04 microg/l (0.04-0.06); p<0.01. In asphyxiated babies, no statistically significant correlations were found between concentrations of cTnI and the other markers of asphyxia. CONCLUSIONS: In asphyxiated neonates, cTnI concentrations are higher with respect to healthy infants, suggesting the presence of myocardial damage in this group of high-risk patients. cTnI does not correlate with the traditional markers of asphyxia.

Asphyxia Neonatorum↗
PubMed2005

Relationship between plasma phospholipid polyunsaturated fatty acid composition and bone disease in renal transplantation.

To investigate the relationship between polyunsaturated fatty acid (PUFA) and bone metabolism in renal transplant patients, plasma phospholipid (PP) PUFA levels, biochemical markers of bone turnover and bone mineral density (BMD) were determined in 22 recipients of a first renal allograft at baseline and after a mean 24.4 month follow-up. A significant increase in PP n-3 PUFA content, in the [n-3 PUFA/ arachidonic acid] ratio and in BMD values was observed, as well as a close correlation between the increase in PP n-3 PUFA content and femoral neck BMD. Multivariate regression analysis showed that BMD improvement was positively related to PP n-3 PUFA variation and baseline PP eicosapentaenoic acid levels, and negatively to PP arachidonic acid modification. Tacrolimus- versus cyclosporine-treated patients demonstrated a significant increase in femoral neck BMD and PP n-3 PUFA content. This is the first longitudinal study showing a link between PP-PUFA composition and bone disease in renal transplantation.

Adult↗
PubMed2005

NT-proBNP in the differential diagnosis of acute dyspnea in the emergency department.

OBJECTIVES: The purpose of this study was to verify the usefulness of NT-proBNP in the differential diagnosis of dyspnea in a population of patients presenting in the ER with breathlessness. DESIGN AND METHODS: In samples from 122 patients presenting in the ER with acute-severe dyspnea and from 25 subjects enrolled as a "comparison group" (NORM), NT-proBNP levels were measured. Patients have been classified on the basis of discharge diagnosis: pulmonary disease (PD, n = 23), pulmonary concomitant to cardiac disease (MIXED, n = 17), pulmonary embolism (EMB, n = 8), cardiac disease (CARD, n = 56), acute myocardial infarction (AMI, n = 11) and other disease (OTHER, n = 7). RESULTS: A significant difference in NT-proBNP values (P <or= 0.05) was found in CARD vs. PD as well as vs. NORM and OTHER groups. 1760 ng/L was the best cut-off value calculated from ROC analysis (AUC +/- SE 0.815 +/- 0.041). Comparing NT-proBNP values and ER diagnosis, a disagreement in 24 patients was observed. Using the discharge diagnosis as the "gold standard," four cases (17%) were found to be FP and 11 cases (46%) were FN according to ER diagnosis, while 2 patients showed false positive and 7 false negative NT-proBNP values. CONCLUSIONS: NT-proBNP measurement represents a useful biochemical tool helping the ER physician in the rapid and reliable recognition of cardiac involvement in patients presenting in the ER with acute-severe dyspnea.

Adult↗
PubMed2005

Secondary hyperparathyroidism is associated with vitamin D receptor polymorphism and bone density after renal transplantation.

Immunosuppresive treatment and secondary hyperparathyroidism (SHPT) are considered among the most important pathogenetic factors for post-renal transplant bone disease. The aim of this study was to investigate the relationships among vitamin D receptor (VDR) gene polymorphism, parathyroid hormone (PTH) levels and bone density in renal transplant recipients. We enrolled 75 patients (50 male and 25 female, mean age 47+/-11 years) who had undergone kidney transplantation 53+/-4 months before. All patients underwent an evaluation of the main biochemical parameters of bone metabolism as well bone densitometry. VDR alleles were typed by a PCR assay based on a polymorphic BsmI restriction site. When patients were categorized according to the VDR genotype (BB, Bb, bb), serum creatinine and the cumulative doses of immunosuppressive drugs were similar across the groups. PTH levels higher than 80 pg/ml were found in 53.6% of the patients, with the highest values being detected in the bb VDR genotype (P<0.05). PTH was significantly correlated to urinary NTx values. Bone density was low in the whole population; however, spinal bone density was lower in the bb subgroup (P<0.02). In the whole population, only PTH (P<0.05) and body mass index (P<0.01) were independent predictors of spinal bone density. Grouping patients by the VDR gene polymorphism, only PTH continued to be an independent predictor of spinal bone density in the bb allele subgroup (R(2) Adj.=0.17). We can conclude that the VDR genotype polymorphism affects bone density of renal transplant recipients via its effects on the severity of SHPT.

Adult↗
PubMed2005

Correlations between clinical presentation, brain natriuretic peptide, big endothelin-1, tumor necrosis factor-alpha and cardiac troponins in heart failure patients.

BACKGROUND: The term "biochemical marker" of heart failure is used to define a biochemical substance whose plasma levels correlate with the clinical and hemodynamic status and predict the prognosis of patients with heart failure. The aim of this study was to prospectively evaluate, in a single population of patients with heart failure, the correlations between the plasma levels of brain natriuretic peptide (BNP), big endothelin-1 (BET-1), tumor necrosis factor-alpha (TNF-alpha), cardiac troponin I (cTnI) and T (cTnT), the clinical presentation, and the left ventricular function. METHODS: The study population included a series of 120 patients (97 males, 81%, mean age 56+/-12 years) in NYHA functional class I (49%), II (20%), III (26%), IV (5%) who were admitted to our institution or followed up as outpatients. All patients underwent cardiologic evaluation, standard electrocardiography, two-dimensional echocardiography, and venous blood sampling on the same day. RESULTS: At univariate analysis the following correlations were found to be significant: all the laboratory parameters correlated with the NYHA class (BNP r = 0.63, BET-1 r = 0.56, cTnI r = 0.25, cTnT r = 0.24, TNF-alpha r = 0.23); BNP (r = -0.39) and BET-1 (r = -0.27) with left ventricular ejection fraction; BNP (r = 0.37) and BET-1 (r = 0.21) with the degree of mitral insufficiency; BNP (r = -0.39), BET-1 (r = 0.25) and TNF-alpha (r = -0.19) with systolic blood pressure; cTnT (r = 0.34), cTnI (r = 0.33), BNP (r = 0.22) and BET-1 (r = 0.19) with heart rate; BNP with age (r = 0.33) and body mass index (r = -0.28). The plasma levels of BNP, BET-1, cTnT and cTnI were significantly higher in case of systemic or pulmonary congestion. At multiple regression analysis the following correlations were still present: BNP with the NYHA functional class (p < 0.005) and with pulmonary venous congestion (p < 0.05); BET-1 with the presence of pulmonary venous congestion (p < 0.005); TNF-alpha with the NYHA class (p < 0.05) and systolic blood pressure (p < 0.001); cardiac troponins with heart rate (p < 0.05). CONCLUSIONS: The plasma concentrations of BNP and BET-1 showed the best and comparable correlations with parameters describing the clinical status of patients with heart failure, in particular with the presence of pulmonary venous congestion. The value of the plasma concentration of TNF-alpha and those of cardiac troponins were found to be limited in patients with relatively stable heart failure.

Biomarkers↗
PubMed2004

Anti-heparan sulphate antibodies and homocysteine in dementia: markers of vascular pathology?

Increasing evidence supports a pathogenic role of heparan sulphate (HS) in the development of dementia. Since HS proteoglycans are present in the endothelial cells and perivascular basement membrane, we wanted to assess blood titres of HS antibodies (Abs) in patients with vascular dementia (VD) and in patients with Alzheimer's disease (AD) with cerebrovascular disease (CVD) [mixed dementia (MixD)]. Moreover, plasma levels of homocysteine, an independent risk factor for the development of dementia as well as for CVD, were also determined. High HS Abs titres were present in one patient with VD and in two patients with mixed dementia, as well as in two neurological control patients (stroke and epilepsy). Increased homocysteine levels were found in 62.5% of patients with mixed dementia, in 22.2% of the VD subjects, in 54.2% of patients with CVD, and in 41.2% of patients with other neurological diseases. The present findings suggest that neither elevated HS Abs titres nor increased homocysteinemia may represent a useful biochemical marker for the diagnosis of VD.

Adolescent↗
PubMed2004

Requirements for improving quality in the measurement of bone markers.

BACKGROUND: A number of biochemical assays readily detect molecules released from the bone matrix and collagen degradation in both serum and urine specimens. The variability of bone biochemical markers is still an issue of practical concern limiting their wider clinical use, and compromising the management of the individual patient. The aim of the present study was to define quality specifications of bone markers measurement in the total testing process. METHODS: The different sources of biological variability of biochemical bone marker were assessed according to the current knowledge and categorized as pre-analytical, intra-analytical and post-analytical. RESULTS: The identification of factors influencing bone marker measurements allowed recommendations to be made for decreasing pre- and intra-analytical variation in order to improve laboratory performance. The assessment of post-analytical sources of variation, moreover, involves the practical use of bone markers in identifying individual women at risk of fractures and the identification of non-responders, providing adequate limit value, least significant change value or optimal threshold of bone marker change. CONCLUSIONS: Laboratory services may improve the potential clinical applications of biochemical markers of bone remodeling by improving method standardization, defining and reducing pre-analytical and analytical variables and providing reports that specify analytical and biological variation or cut-off values, thus facilitating data interpretation or reports.

Analysis of Variance↗
PubMed2004

Cord blood cardiac troponin T and troponin I levels in multiple-gestation neonates.

The increased mortality and morbidity rates in multiple-gestation neonates are not completely understood. Troponin measurements have a role in situations where the evaluation of the cardiac damage is difficult, such as in cases of unexplained intrauterine fetal growth restriction or death. These conditions, along with perinatal hypoxic risk and in utero ischemic damage, are frequently found in multiple gestations. In this context, a myocardial damage could be expected more frequently in multiple than in singleton births. We hypothesized that cord blood cardiac troponin T and troponin I, markers of myocardial damage, could be different between singleton and multiple pregnancies and, among twins, between the first- and the second-born twin. Troponins T and I and creatine kinase MB concentrations were not increased in twins at birth and were not different between the first- and the second-born twin. These data suggest that myocardial damage, evaluated by cardiac troponin T, troponin I, and creatine kinase MB measurements, does not seem to be a relevant problem in multiple-gestation neonates.

Birth Order↗
PubMed2004

External quality assessment for biochemical markers of myocardial damage: an Italian experience.

In 1999 the Centre of Biomedical Research (CRB) in co-operation with the Italian interdisciplinary and intersociety Working Group on Markers of Myocardial Damage proposed a national external quality assurance scheme that was granted in accordance with the UK Clinical Pathology Accreditation Standards in 2001. The scheme, which stresses the importance of educational aspects in quality assurance, was scientifically designed to ensure that it would provide an objective assessment of participants' performance and promote quality improvements to meet the needs of participants. The present paper reports on the data collected in EQA cycles conducted to evaluate improvements in the performance of participants and in related methods. The findings obtained demonstrate that during the 4-year experience the scheme provided opportunities to improve the performance of laboratories and promoted an efficient, more satisfactory approach to analytical aspects. The number of unacceptable performances decreased from 11.6% to 5.6% for troponin I, from 19.5% to 9.0% for myoglobin and from 13.2% to 4.3% for creatine kinase myocardial isoenzyme (CK-MB). During cycles in 2001 and 2002, inter-variability (coefficient of variation, CV%) data for all markers appeared satisfactory and showed a significant improvement (lower than 10%), in particular for procedures automated on Dade Behring Dimension and Beckman Access systems. However, reference values/decisional limits declared by laboratories and those suggested by the manufacturers are not comparable, even within the same diagnostic system. The findings demonstrate that participation in EQA schemes provided an opportunity for participating laboratories to continuously improve the quality of their services.

Biomarkers↗
PubMed2004

Plasma levels of tumor necrosis factor-alpha correlate with the six-minute walk test results in patients with mild to moderate heart failure.

BACKGROUND: The plasma levels of brain natriuretic peptide, tumor necrosis factor-alpha, big endothelin-1 and cardiac troponins have been reported to correlate with the severity of heart failure. METHODS: In a single population of 80 outpatients with mild to moderate chronic heart failure the correlation between the patient's functional capacity, as evaluated at a 6-min walk test, the clinical parameters and plasma levels of brain natriuretic peptide, tumor necrosis factor-alpha, big endothelin-1 and cardiac troponins was evaluated. RESULTS: A significant inverse correlation was found with the patient's age (p < 0.0001), NYHA functional class (p < 0.0001), left ventricular dysfunction etiology (ischemic vs dilated cardiomyopathy, p < 0.0005), heart rate (p < 0.05), plasma levels of brain natriuretic peptide (p < 0.05) and of tumor necrosis factor-alpha (p < 0.0005). At multiple regression analysis a correlation was found between the 6-min walk test results and the patient's age (p < 0.05), NYHA functional class (p < 0.01), left ventricular dysfunction etiology (ischemic vs dilated cardiomyopathy, p < 0.05) and tumor necrosis factor-alpha plasma levels (p < 0.05). CONCLUSIONS: In our patients with mild to moderate heart failure, a significant correlation was found between the results of the 6-min walk test and only the plasma concentrations of tumor necrosis factor-alpha among the laboratory parameters analyzed in this study.

Adult↗