Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 57
Filter
1.
Inorg Chem ; 61(46): 18400-18411, 2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36331210

ABSTRACT

The challenging issue of spent nuclear fuel (SNF) management is being tackled by developing advanced technologies that point to reduce environmental footprint, long-term radiotoxicity, volumes and residual heat of the final waste, and to increase the proliferation resistance. The advanced recycling strategy provides several promising processes for a safer reprocessing of SNF. Advanced hydrometallurgical processes can extract minor actinides directly from Plutonium and Uranium Reduction Extraction raffinate by using selective hydrophilic and lipophilic ligands. This research is focused on a recently developed N-heterocyclic selective lipophilic ligand for actinides separation to be exploited in advanced Selective ActiNide EXtraction (SANEX)-like processes: 2,6-bis(1-(2-ethylhexyl)-1H-1,2,3-triazol-4-yl)pyridine (PyTri-Ethyl-Hexyl-PTEH). The formation and stability of metal-ligand complexes have been investigated by different techniques. Preliminary studies carried out by electrospray ionization mass spectrometry (ESI-MS) analysis enabled to qualitatively explore the PTEH complexes with La(III) and Eu(III) ions as representatives of lanthanides. Time-resolved laser fluorescence spectroscopy (TRLFS) experiments have been carried out to determine the ligand stability constants with Cm(III) and Eu(III) and to better investigate the ligand complexes involved in the extraction process. The contribution of a 1:3 M/L complex, barely identified by ESI-MS analyses, was confirmed as the dominant species by TRLFS experiments. To shed light on ligand selectivity toward actinides over lanthanides, NMR investigations have been performed on PTEH complexes with Lu(III) and Am(III) ions, thereby showing significant differences in chemical shifts of the coordinating nitrogen atoms providing proof of a different bond nature between actinides and lanthanides. These scientific achievements encourage consideration of this PyTri ligand for a potential large-scale implementation.

2.
Ind Eng Chem Res ; 61(12): 4436-4444, 2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35370355

ABSTRACT

Within a spent nuclear fuel recycling strategy, in the past few years, the pyridine-bis-triazole unit was found to be rather effective and selective in minor actinide (MA) separation from synthetic high active raffinate (HAR). In this research work, the main features of the recently studied PTEH ligand were investigated in order to evaluate its potentialities in SANEX-like processes. Its applicability in advanced separation processes was demonstrated, even at process temperatures. It manifested satisfactory extraction properties for a successful selective An separation from Ln, easy cation release, and adequate extraction kinetics as well as outstanding hydrolytical and radiolytical stability. All the results collected in this work allowed the scientists on the committee of the H2020 GENIORS project to promote PTEH as a concrete alternative to the reference CyMe4-BTBP ligand.

3.
ACS Omega ; 6(5): 3602-3611, 2021 Feb 09.
Article in English | MEDLINE | ID: mdl-33644525

ABSTRACT

In this communication, we report on the use of deep eutectic solvents (DESs) for processing nuclear waste, with a view to selectively recovering minor actinides (MA) from highly active raffinate solutions. DESs are an interesting new class of green and eco-sustainable solvents. Herein, a representative family of DES was tested as a co-solvent for MA/lanthanides partitioning based on Selective ActiNide EXtraction (SANEX)-like hydrometallurgical processes. The reference system exploits the CyMe4-BTBP lipophilic extractant for selective MA recovery, but the slow kinetics is the main limitation toward the industrial implementation. A selection of hydrophilic DESs has been proposed as a phase transfer catalyst and tested to improve the process performances. In this work, the radiochemical stability and the extraction behavior of these DESs have been ascertained. Moreover, a preliminary optimization of system composition has been achieved. This study underlines a catalytic effect of DES that can be proficiently exploited to enhance CyMe4-BTBP extraction and selectivity.

4.
RSC Adv ; 10(33): 19629-19635, 2020 May 20.
Article in English | MEDLINE | ID: mdl-35515445

ABSTRACT

The conformational isomerism of the chelating agent 2,6-bis(1-(3-hydroxypropyl)-1,2,3-triazol-4-yl)pyridine (PTD), exploited in fuel reprocessing in spent nuclear waste, has been studied by single crystal X-ray diffraction analysis in combination with an extensive DFT conformational investigation. In the solid-state, the elucidated crystal structure (i.e., not yet published) shows that by thermal treatment (DSC) no other phases are observed upon crystallization from the melt, indicating that the conformation observed by X-ray data is rather stable. Mapping of intermolecular and intramolecular noncovalent interactions has been used to elucidate the unusual arrangement of the asymmetric unit. Considerations relating to the stability of different conformational isomers in aqueous and non-aqueous solutions are also presented. The accurate structural description reported here might open various research topics such as the potential of PTD to act as an outer sphere ligand in the formation of second sphere coordination complexes and their interconversion by mechanochemical means.

5.
Inorg Chem ; 58(21): 14642-14651, 2019 Nov 04.
Article in English | MEDLINE | ID: mdl-31609595

ABSTRACT

The "CHON" compatible water-soluble ligand 3,3'-(pyridine-2,6-diylbis(1H-1,2,3-triazole-4,1-diyl))bis(propan-1-ol) (PTD) has shown promise for selectively stripping actinide ions from an organic phase containing both actinide and lanthanide ions, by preferential complexation of the former. Aiming at improving its complexation properties, PTD-OMe was synthesized, bearing a methoxy group on the central pyridine ring, thus increasing its basicity and hence complexation strength. Unfortunately, solvent extraction experiments in the range of 0.1-1 mol/L nitric acid proved PTD-OMe to be less efficient than PTD. This behavior is explained by its greater pKa value (pKa = 2.54) compared to PTD (pKa = 2.1). This counteracts its improved complexation properties for Cm(III) (log ß3(PTD-OMe) = 10.8 ± 0.4 versus log ß3(PTD) = 9.9 ± 0.5).

6.
Inorg Chem ; 56(4): 2135-2144, 2017 Feb 20.
Article in English | MEDLINE | ID: mdl-28151663

ABSTRACT

The complexation of Cm(III) and Eu(III) with the novel i-SANEX complexing agent 2,6-bis[1-(propan-1-ol)-1,2,3-triazol-4-yl]pyridine (PTD) was studied by time-resolved laser fluorescence spectroscopy (TRLFS). The formation of 1:3, 1:2, and 1:1 metal/ligand complexes was identified upon increasing PTD concentration in 10-3 mol/L HClO4 and in 0.44 mol/L HNO3 solutions. For all these complexes, stability constants were determined at different acid concentrations. Though under the extraction conditions proposed for an An/Ln separation process, that is, for 0.08 mol/L PTD in 0.44 mol/L HNO3, 1:3 complexes represent the major species, a significant fraction of 1:2 complexes was found. This is caused by ligand protonation, and results in lower Eu(III)/Am(III) separation factors compared to SO3-Ph-BTP, until now considered the i-SANEX reference ligand. Focused extraction studies performed at lower proton concentration, where the 1:3 complex is formed exclusively, confirm this assumption.

7.
J Am Chem Soc ; 138(23): 7232-5, 2016 06 15.
Article in English | MEDLINE | ID: mdl-27203357

ABSTRACT

There is still an evident need for selective and stable ligands able to separate actinide(III) from lanthanide(III) metal ions in view of the treatment of the accumulated radioactive waste and of the recycling of minor actinides. We have herein demonstrated that hydrophilic 2,6-bis-triazolyl-pyridines are able to strip all actinides in all the different oxidation states from a diglycolamide-containing kerosene solution into an acidic aqueous phase. The ascertained high actinide selectivity, efficiency, extraction kinetics, and chemical/radiolytic stability spotlight this hydrophilic class of ligands as exceptional candidates for advanced separation processes fundamental for closing the nuclear fuel cycle and solving the environmental issues related to the management of existing nuclear waste.


Subject(s)
Actinoid Series Elements/chemistry , Lanthanoid Series Elements/chemistry , Nuclear Energy , Pyridines/chemistry , Radioactive Waste/prevention & control , Hydrophobic and Hydrophilic Interactions , Kinetics , Ligands , Models, Chemical , Oxidation-Reduction , Radiochemistry
8.
Meat Sci ; 103: 83-9, 2015 May.
Article in English | MEDLINE | ID: mdl-25637742

ABSTRACT

This work describes a metabolic profiling study of non-irradiated and irradiated beef (at 2.5, 4.5 and 8 kGy) using (1)H NMR and chemometrics. The assignment of all major NMR signals of the aqueous/methanolic extracts was performed. A comprehensive multivariate data analysis proved the ability to distinguish between the irradiated and non-irradiated beef. Classification trees revealed that three metabolites (glycerol, lactic acid esters and tyramine or a p-substituted phenolic compound) are important biomarkers for classification of the irradiated and non-irradiated beef samples. Overall, the achieved metabolomic results show that the changes in the metabolic profile of meat provide a valuable insight to be used in detecting irradiated beef. The use of the NMR-based approach simplifies sample preparation and decrease the time required for analysis, compared to available official analytical procedures.


Subject(s)
Food Analysis/methods , Food Irradiation , Gamma Rays , Metabolome , Metabolomics/methods , Red Meat/analysis , Animals , Cattle , Esters/analysis , Food Irradiation/classification , Glycerol/analysis , Humans , Lactic Acid/analysis , Magnetic Resonance Spectroscopy/methods , Multivariate Analysis , Phenols/analysis , Tyramine/analysis
9.
Dalton Trans ; 42(48): 16930-8, 2013 Dec 28.
Article in English | MEDLINE | ID: mdl-24091998

ABSTRACT

Four lipophilic 1,10-phenanthroline di(thio)amide, diester or diketone derivatives were studied as ligands for Am(III)/Eu(III) separation from acidic media. The synthesis of these compounds is reported together with the extraction tests in different solvents (kerosene, octanol and o-nitrophenyl hexyl ether), HNO3 concentrations and ratios between the ligand and the synergistic agent (Br-Cosan). The promising results obtained from the large number of solvent extraction tests carried out show that it might be possible to apply this class of ligands to advanced reprocessing of spent nuclear fuel. The experimental data indicate that, under the conditions that simulate the real radioactive waste, the extraction efficiency and Am/Eu separation factors are particularly high, thus suggesting that the combination of soft heterocyclic N-donor atoms and hard carbonyl groups of ester and amides affords a tetradentate donor set of atoms (ONNO) that gives rise to remarkable selectivities. ESI-MS studies and DFT calculations shed light on the possible structure of the Eu(3+) complexes indicating that the 1 : 1 : 2 (cation : ligand : anion) complex is slightly more stable than the 1 : 2 : 1 species.

10.
Meat Sci ; 93(2): 171-7, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23022578

ABSTRACT

The combination of (1)H NMR lipid profiling with multivariate analysis was applied to differentiate irradiated and non-irradiated beef. Two pattern recognition chemometric procedures, stepwise linear discriminant analysis (sLDA) and artificial neural networks (ANNs), provided a successful discrimination between the groups investigated. sLDA allowed the classification of 100% of the samples into irradiated or non-irradiated beef groups; the same result was obtained by ANNs using the 1 kGy irradiation dose as discriminant value suggested by the network. Furthermore, sLDA allowed the classification of 81.9% of the beef samples according to the irradiation dose (0, 2.5, 4.5 and 8 kGy). (1)H NMR lipid profiling, coupled with multivariate analysis may be considered a suitable and promising screening tool for the rapid detection of irradiated meat in official control of food.


Subject(s)
Food Irradiation , Lipids/analysis , Meat/analysis , Meat/radiation effects , Animals , Cattle , Cyclobutanes/analysis , Discriminant Analysis , Magnetic Resonance Spectroscopy , Multivariate Analysis , Neural Networks, Computer
11.
Biometals ; 25(3): 569-76, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22438029

ABSTRACT

Multiple sclerosis (MS) is a chronic progressive disease of the central nervous system (CNS) provoking disability and neurological symptoms. The exact causes of SM are unknown, even if it is characterized by focal inflammatory lesions in CNS accompanied by autoimmune reaction against myelin. Indeed, many drugs able to modulate the immune response of patients have been used to treat MS. More recently, toxic metals have been proposed as possible causes of neurodegenerative diseases. The objective of this study is to investigate in vivo the impact of heavy metal intoxication in MS progression. We studied the case of a patient affected by MS, who has been unsuccessfully treated for some years with current therapies. We examined his levels of toxic heavy metals in the urine, following intravenous "challenge" with the chelating agent calcium disodium ethylene diamine tetraacetic acid (EDTA).The patient displayed elevated levels of aluminium, lead and mercury in the urine. Indeed, he was subjected to treatment with EDTA twice a month. Under treatment, the patient revealed in time improved symptoms suggestive of MS remission. The clinical data correlated with the reduction of heavy metal levels in the urine to normal range values. Our case report suggests that levels of toxic metals can be tested in patients affected by neurodegenerative diseases as MS.


Subject(s)
Chelating Agents/therapeutic use , Metals, Heavy/metabolism , Multiple Sclerosis/drug therapy , Multiple Sclerosis/metabolism , Adult , Edetic Acid , Humans , Male , Young Adult
12.
Dalton Trans ; 39(10): 2546-53, 2010 Mar 14.
Article in English | MEDLINE | ID: mdl-20179847

ABSTRACT

The effect of a systematic variation of the basicity of the pyridine nitrogen atom in calix[6]arene-based picolinamide ligands on the actinide(III)/lanthanide(III) separation by solvent extraction has been investigated. The distribution coefficients for trivalent metal ions (D(M)) decrease by increasing the nitric acid concentration, but for ligands (2 and 4) possessing a much less basic aromatic nitrogen atom, D(M) values are considerably higher than those of ligands (1 and 5) having more basic pyridine nuclei. Also in terms of selectivity ligands 2 and 4 behave better than ligand 1 especially at nitric acid concentrations very close to those of the nuclear waste. At [H(+)] = 1 mol L(-1), SF(Am/Eu) are still 3.23 and 1.92 for 2 and 4, respectively. A simple quantitative relationship between the efficiency of these extractants and the gas-phase basicity of suitably chosen model compounds is proposed, in order to explain the experimental extraction data, on one hand, and to orient future syntheses of ligands for An/Ln separation, on the other hand.

13.
Eur Heart J ; 29(23): 2886-93, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18948356

ABSTRACT

AIMS: The aim of the present study was to describe a 10 years single-centre experience in pacing and defibrillating leads removal using an effective and safe modified mechanical dilatation technique. METHODS AND RESULTS: We developed a single mechanical dilating sheath extraction technique with multiple venous entry site approaches. We performed a venous entry site approach (VEA) in cases of exposed leads and an alternative transvenous femoral approach (TFA) combined with an internal transjugular approach (ITA) in the presence of very tight binding sites causing failure of VEA extraction or in cases of free-floating leads. We attempted to remove 2062 leads [1825 pacing and 237 implantable cardiac defibrillating (ICD) leads; 1989 exposed at the venous entry site and 73 free-floating] in 1193 consecutive patients. The VEA was effective in 1799 leads, the TFA in 28, and the ITA in 205; in the overall population, we completely removed 2032 leads (98.4%), partially removed 18 (0.9%), and failed to remove 12 leads (0.6%). Major complications were observed in eight patients (0.7%), causing three deaths (0.3%). CONCLUSION: Mechanical single sheath extraction technique with multiple venous entry site approaches is effective, safe, and with a good cost effective profile for pacing and ICD leads removal.


Subject(s)
Defibrillators, Implantable , Device Removal/methods , Dilatation/methods , Pacemaker, Artificial , Adolescent , Adult , Aged , Aged, 80 and over , Cardiac Catheterization/methods , Child , Dilatation/instrumentation , Female , Humans , Male , Middle Aged , Monitoring, Physiologic/methods , Treatment Outcome , Young Adult
14.
Cardiology ; 109(4): 241-8, 2008.
Article in English | MEDLINE | ID: mdl-17873488

ABSTRACT

OBJECTIVE: Aim of this study was to investigate the effect of weight loss on structural and functional myocardial alterations in severely obese subjects treated with bariatric surgery. PATIENTS AND METHODS: Thirteen severely obese patients (2 males and 11 females) were enrolled in the study. All subjects underwent conventional 2D color Doppler echocardiography. The new ultrasonic techniques used were: (a) integrated backscatter for the analysis of myocardial reflectivity, referred to pericardial interface as expression of myocardial structure (increase in collagen content) and of cyclic variation index as expression of intrinsic myocardial contractility and (b) color Doppler myocardial imaging (CDMI) for the analysis of strain and strain rate (myocardial deformability). All subjects underwent bariatric surgery and were resubmitted to echocardiographic and biochemical examination 6-24 months after surgery. RESULTS: The main finding of the present study was a quite complete normalization of myocardial functional and structural alterations after weight loss. In particular, the cyclic variation index at septum level improved from 14.6 +/- 7.0 before to 25.7 +/- 11.2 (means +/- SD) after surgery (controls: 36.2 +/- 9.1). Mean reflectivity at septum level significantly decreased from 55.8 +/- 9.5 to 46.5 +/- 8.8 (controls: 43.0 +/- 8.0). Also, the strain at septum level significantly improved after surgery (from -11.9 +/- 3.2 to -20.4 +/- 5.3; controls: -23.4 +/- 9). CONCLUSION: This study establishes: (a) the utility of new ultrasonic techniques to detect very early structural and functional myocardial alterations in severely obese patients, and (b) the regression of these subclinical abnormalities after weight loss achieved by bariatric surgery.


Subject(s)
Bariatric Surgery , Heart/physiopathology , Myocardium/pathology , Obesity/surgery , Adult , Echocardiography, Doppler, Color , Female , Humans , Male , Severity of Illness Index , Treatment Outcome , Weight Loss
15.
Atherosclerosis ; 197(1): 346-54, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17631295

ABSTRACT

BACKGROUND: Hypercholesterolemia contributes to coronary heart disease but little is known about its direct effect on myocardial function. We evaluated left ventricular function using echocardiography and the effect of treatment with rosuvastatin in a group of patients with primary hypercholesterolemia. METHODS AND RESULTS: Thirty-three patients with primary hypercholesterolemia (HC) and without evidence of coronary heart disease and 25 aged matched healthy volunteers (C) were submitted to conventional echocardiography, pulsed wave tissue Doppler imaging (PWTDI), color Doppler myocardial imaging (CDMI) and integrated backscatter (IBS). Echocardiographic evaluation was repeated after 6 months of treatment with rosuvastatin (10mg/day) in 17 patients. Compared with C, patients with HC showed lower E/A ratio (p<0.0001) and higher Tei index mit (p<0.0001), as well as lower PW TDI E/A both at septum (p<0.0001) and at lateral level (p<0.0001) and higher modified Tei index both at septal annulus (p<0.0001) and lateral annulus (p<0.0001). Integrated backscatter parameters were significantly reduced in patients with HC (CVIsept p<0.0001 and CVI post wall p<0.05). CDMI derived indices in the two groups were not different. After 6 months of Rosuvastatin treatment a significant reduction of LDL cholesterol levels (51%, p<0.0001) was registered in HC patients together with a significant improvement of longitudinal global systolic and diastolic function (Tei index) and myocardial intrinsic contractility (CVI). CONCLUSIONS: These data suggest that in patients with hypercholesterolemia exists an early cardiomyopathy characterized by systolic and diastolic dysfunction. That could produce a substratum for an "impaired preconditioning". Rosuvastatin seems able to revert systolic abnormalities.


Subject(s)
Fluorobenzenes/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hypercholesterolemia/complications , Hypercholesterolemia/drug therapy , Pyrimidines/administration & dosage , Sulfonamides/administration & dosage , Ventricular Dysfunction, Left/drug therapy , Ventricular Dysfunction, Left/etiology , Adult , Blood Flow Velocity , Densitometry , Diastole , Echocardiography, Doppler, Color , Follow-Up Studies , Humans , Middle Aged , Pilot Projects , Rosuvastatin Calcium , Systole , Ventricular Dysfunction, Left/diagnostic imaging
16.
Am J Cardiol ; 99(1): 84-90, 2007 Jan 01.
Article in English | MEDLINE | ID: mdl-17196468

ABSTRACT

The aim of this study was to determine whether early myocardial structural and functional systolic and diastolic alterations in asymptomatic and uncomplicated patients with type 1 diabetes mellitus (DM) could be detected using the new highly sensitive echocardiographic techniques of integrated backscatter and color Doppler myocardial imaging. Forty asymptomatic and uncomplicated patients with type 1 DM and 40 gender- and age-matched normal controls were studied. All patients were analyzed by conventional and new echocardiographic techniques (integrated backscatter and color Doppler myocardial imaging). Patients with DM showed reduced systolic function compared with controls, evidenced by significantly lower peak strain, strain rates, and cyclic variation indexes at the septum (p <0.0001, <0.01, and <0.001, respectively) and at the posterior wall level (p <0.0001, <0.0001, and <0.001, respectively). On receiver-operating characteristic curve analysis, systolic strain and the cyclic variation index showed the highest discriminating power for separating patients with DM and control subjects. Neither structural or ultrastructural nor diastolic functional abnormalities were detected. On univariate regression analysis, a significant inverse correlation was found for DM duration with conventional (E/A ratio) and unconventional (tissue Doppler imaging E/A ratio) indexes of diastolic function, in the absence of any correlation for systolic function. In conclusion, highly sensitive ultrasonic techniques demonstrate evidence of left ventricular systolic dysfunction in the early stage of type 1 DM, in the absence of ultrastructural and left ventricular diastolic functional abnormalities.


Subject(s)
Diabetes Mellitus, Type 1 , Ventricular Dysfunction, Left/physiopathology , Adult , Blood Pressure , Case-Control Studies , Echocardiography, Doppler, Color , Female , Humans , Male , ROC Curve , Ventricular Dysfunction, Left/diagnostic imaging
17.
Coron Artery Dis ; 17(8): 693-8, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17119378

ABSTRACT

OBJECTIVE: To evaluate the prognostic value of a single and early determination of high sensitivity C-reactive protein levels at admittance in patients with acute myocardial infarction with persistent ST elevation. PATIENTS AND METHODS: We evaluated high-sensitivity C-reactive protein levels in 247 consecutive acute myocardial infarction with persistent ST elevation patients at admittance. Patients were monitored for the occurrence of major adverse cardiovascular events. RESULTS: Mean follow-up was 26 months. High C-reactive protein levels were principally associated with age > or = 65 years (P=0.01), diabetes (P=0.03) and reduced left ventricle ejection fraction (P=0.048). We observed a significant C-reactive protein level difference between the major adverse cardiovascular event-free group and the major adverse cardiovascular event group (28.2+/-21.9 vs. 47.7+/-31.9 mg/l, P=0.03), between deceased patients group (vs. 81.5+/-51.8 mg/l, P<0.001) and early deaths (vs. 129.5+/-71.9 mg/l, P<0.001). Kaplan-Meier plots for survival and major adverse cardiovascular event occurrence showed a significant separation (P=0.01 and 0.002 by log-rank test, respectively) between high and low C-reactive protein level groups. C-reactive protein levels were independent risk predictors of major adverse cardiovascular events (odds ratio 2.931, 95% confidence interval 1.512-5.893; P=0.046) and death (odds ratio 5.068, 95% confidence interval 2.056-20.195; P=0.04). Patients with high C-reactive protein levels and age > or = 65 years were at highest risk for major adverse cardiovascular event occurrence (odds ratio 5.658, 95% confidence interval 2.898-6.249; P=0.022) and death (odds ratio 8.120, 95% confidence interval 5.656-22.729; P=0.03). CONCLUSIONS: High C-reactive protein levels identify patients with a worse prognosis after acute myocardial infarction with persistent ST elevation. The evaluation of C-reactive protein and age may provide a tool to select high-risk patients.


Subject(s)
C-Reactive Protein/metabolism , Electrocardiography , Myocardial Infarction , Patient Admission , Aged , Biomarkers/blood , Female , Follow-Up Studies , Humans , Italy/epidemiology , Male , Middle Aged , Myocardial Infarction/blood , Myocardial Infarction/mortality , Myocardial Infarction/physiopathology , Nephelometry and Turbidimetry , Prognosis , Retrospective Studies , Risk Factors , Survival Rate/trends
18.
J Cardiovasc Med (Hagerstown) ; 7(11): 835-7, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17060812

ABSTRACT

Cardiac toxicity is an uncommon side-effect of 5-fluorouracil (5-FU) treatment, consisting mainly of chest pain episodes with or without electrocardiographic changes and dysrhythmias. Here, we describe the case of a 56-year-old male patient with a diagnosis of advanced colorectal cancer who developed an acute myocardial infarction during 5-FU infusion. The patient was not affected by prior heart disease and did not show any classic risk factors for coronary heart disease. Coronary angiography examination revealed no evidence of coronary stenosis, supporting the hypothesis of a coronary artery spasm related to 5-FU infusion. Given the great number of cancer patients receiving 5-FU containing chemotherapeutic regimens, this rare but severe cardiac side-effect may be observed in both cardiologic and oncologic clinical practice. We suggest a tight clinical monitoring of all patients receiving 5-FU infusions, even in those without a prior history of heart disease.


Subject(s)
Antimetabolites, Antineoplastic/adverse effects , Colorectal Neoplasms/drug therapy , Fluorouracil/adverse effects , Myocardial Infarction/chemically induced , Antimetabolites, Antineoplastic/administration & dosage , Coronary Angiography , Creatine Kinase, MB Form/blood , Electrocardiography , Fluorouracil/administration & dosage , Humans , Infusions, Intravenous , Male , Middle Aged , Myocardial Infarction/blood , Myocardial Infarction/physiopathology , Time Factors , Troponin I/blood
19.
J Am Soc Echocardiogr ; 19(8): 1063-71, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16880104

ABSTRACT

Obesity is a well-established risk factor for congestive heart failure. Evidence has been provided indicating that insulin resistance could be the mediator between obesity and congestive heart failure, but the pathogenic mechanisms leading to myocardial alterations remain unclear. The aim of this study was to investigate, by ultrasonic integrated backscatter (IBS) analysis, subclinical alterations of left ventricular (LV) structure and function in severe obesity. Sixty consecutive, severely obese people, who were otherwise healthy (15 men, 45 women; mean age +/- SD = 31.8 +/- 7 years), were enrolled. A total of 48 sex- and age-matched nonobese healthy participants were recruited as control subjects. All participants underwent conventional 2-dimensional color Doppler echocardiography, pulsed wave Doppler tissue imaging at mitral annulus level, and IBS. The homeostasis model assessment insulin resistance index was used to assess insulin resistance; the index values in the obese group were significantly higher (mean +/- SD = 4.9 +/- 1.4) than in the control group (0.92 +/- 0.5, P < .0001). Obese patients had a greater LV mass index by height (58.5 +/- 14 g/m(2.7)) than did control subjects (37 +/- 8 g/m(2.7), P < .0001) because of compensation response to volume overload caused by a greater cardiac output (P < .02). Preload reserve was increased in obese patients, as demonstrated by the significant increase in left atrial dimension (P < .0001). This volumetric increase activated the Frank-Starling mechanism, and determined a significantly higher LV ejection fraction (P < .03) in obese patients as compared with control subjects. A slightly reduced LV diastolic function was demonstrated in obese patients (transmitral early to late peak diastolic transmitral flow velocities ratio = 1.1 +/- 0.7) as compared with control subjects (1.5 +/- 0.5, P < .02). Pulsed wave Doppler tissue imaging showed an impairment of diastolic LV longitudinal function and increased LV diastolic filling pressure. The IBS values at septum level, indexed by pericardium interface, were significantly higher for septum in the obese group (57.8 +/- 8%) than in the control group (42.3 +/- 9%, P < .0001). Additional IBS alterations were observed in the obese group, with a significantly lower cyclic variation index both at septum (P < .0001) and at posterior wall (P < .001) levels. A significant association was found between insulin resistance index and both the IBS index of myocardial reflectivity at septum level (expression of increased myocardial collagen content) or LV mass. In conclusion, this study demonstrates that obese patients exhibit myocardial structural and functional alterations related to insulin resistance and to LV volume overload, which could be considered the very early stage of incipient obesity cardiomyopathy.


Subject(s)
Cardiomyopathies/diagnostic imaging , Cardiomyopathies/epidemiology , Echocardiography, Doppler, Color/statistics & numerical data , Obesity/diagnostic imaging , Obesity/epidemiology , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/epidemiology , Adult , Comorbidity , Evidence-Based Medicine , Female , Humans , Incidence , Italy/epidemiology , Male , Prognosis , Risk Assessment/methods , Risk Factors
20.
Eur J Endocrinol ; 155(1): 3-9, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16793943

ABSTRACT

The aim of the present study was to evaluate cardiac function and texture in patients with subclinical hypothyroidism (sHT) both by conventional and new ultrasonic intramyocardial tissue techniques. sHT was characterized by normal serum free tetraiodotironine and free triiodotironine levels and slightly increased serum TSH level. Twenty-four patients affected by sHT and 24 sex- and age-matched healthy volunteers were studied. All subjects were submitted to conventional two-dimensional (2D)-color Doppler echocardiography, pulsed wave tissue Doppler imaging (PWTDI) for the analysis of the diastolic function, color Doppler myocardial imaging (CDMI) for the analysis of regional strain and strain-rate and integrated backscatter (IBS) for the evaluation of intrinsic contractility and tissue characterization. The results of the present study were: (a) the detection in sHT subjects of a lower cyclic variation index (CVI) indicating an altered myocardial intrinsic contractility; (b) a higher ultrasonic myocardial reflectivity indicating an altered myocardial texture; (c) the detection of lower systolic strain and strain-rate indicating an alteration of myocardial regional deformability; (d) an initial impairment of left ventricular diastolic function indicated by a decrease of peak E mitral flow velocity and an increase of peak A mitral flow velocity. All parameters studied with conventional 2D-echo in sHT patients were comparable with controls, except for a mild alteration in diastolic function. A significant correlation among systo-diastolic modifications detected by CDMI and IBS and serum TSH levels were found. The CVI at septum, the PWDTI S-peak wave and the systolic strain at septum were inversely related to the serum TSH levels. In conclusion, the new intramyocardial ultrasonic techniques confirm and extend the previous knowledge on the effect of the sHT on the heart, allowing the detection of early ultrastructural and regional functional systolic and diastolic abnormalities.


Subject(s)
Hypothyroidism/pathology , Myocardium/pathology , Ventricular Dysfunction, Left/etiology , Adult , Aortic Valve Stenosis/etiology , Aortic Valve Stenosis/physiopathology , Densitometry , Echocardiography , Female , Fibrosis/pathology , Heart Rate/physiology , Heart Ventricles/pathology , Heart Ventricles/physiopathology , Humans , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/physiopathology , Hypothyroidism/diagnostic imaging , Hypothyroidism/physiopathology , Male , Myocardial Contraction/physiology , Thyroid Hormones/blood , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/physiopathology
SELECTION OF CITATIONS
SEARCH DETAIL
...