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Maurizia Baldi

Publications and source records attributed to Maurizia Baldi.

11 recordsLinked to original sources
PubMed2006

Neutrophils from patients with TNFRSF1A mutations display resistance to tumor necrosis factor-induced apoptosis: pathogenetic and clinical implications.

OBJECTIVE: To explore tumor necrosis factor (TNF)-induced apoptosis in neutrophils from patients with TNF receptor-associated periodic syndrome (TRAPS) and to correlate the results with the different kinds of TNFRSF1A mutations. METHODS: Two hundred sixty-five patients with clinically suspected inherited autoinflammatory syndrome were screened for mutations of the TNFRSF1A gene. Neutrophils were isolated from heparinized blood by dextran sedimentation and incubated with and without cycloheximide (CHX) and TNFalpha. Cell apoptosis was assessed by human annexin V binding, and caspase 8 activation was assessed by flow cytometry. RESULTS: Twenty-one patients were found to carry a variant of the TNFRSF1A gene: 13 patients had an R92Q substitution, and 8 patients presented other missense substitutions, 1 splicing mutation, and 1 in-frame interstitial deletion. Neutrophil stimulation with TNF and CHX was associated with induction of apoptosis in 12 normal controls and in 10 subjects with the R92Q mutation. Conversely, neutrophils from 8 TRAPS patients with mutations of cysteine or threonine residues or interstitial deletion did not show any induction of apoptosis after stimulation. The incidence of the R92Q mutation among patients with recurrent autoinflammatory syndromes was similar to that observed in the normal population. CONCLUSION: Resistance to TNF-mediated apoptosis is a feature in TRAPS patients who have mutations of cysteine residues or interstitial deletion, and may play a pathogenic role. The R92Q mutation does not appear to be significantly associated with TRAPS.

Adult↗
PubMed2005

Scar detection by contrast-enhanced magnetic resonance imaging in chronic coronary artery disease: a comparison with nuclear imaging and echocardiography.

We compared contrast-enhanced MRI (CeMRI) with the most widely used imaging techniques for myocardial infarct (MI) diagnosis, SPECT and Echo, in unselected patients with chronic coronary artery disease (CAD). Two blinded operators assessed scars on MRI, SPECT and Echo images using a 16-segments LV model. We studied 105 consecutive patients: 50 had Q-wave MI (Q-MI), 19 non Q-wave MI or rest angina (nonQ-MI/RA) and 36 effort angina (EA) history. CeMRI was positive, respectively, in 96%, 37%, and 6%, SPECT in 90%, 53%, and 44%, and Echo in 84%, 32%, and 28% of patients (within Q-MI: CeMRI vs. SPECT p < 0.03, vs. Echo p < 0.001; within EA CeMRI vs. SPECT and ECHO p < 0.001; all trends p < 0.001, pseudo r-square: 0.56-0.75 for CeMRI, 0.18-0.28 for SPECT and 0.23-0.37 for Echo). CeMRI and SPECT agreed in 83 patients (79%); negative SPECT with 1 +/- 0 segments subendocardial delayed enhancement (DE) was found in 4 (4%); negative CeMRI with 4 +/- 3 segments perfusion defects in 18 (17%), 16 of whom were obese or showed LBB or sub-occlusion of related coronary. CeMRI and Echo agreed in 78 patients (75%); negative Echo with 2 +/- 1 segments subendocardial DE was found in 13 (12%) and negative CeMRI with 11 +/- 7 segments kinetic abnormalities in 14 (13%), in 10 confirmed by Cine-MRI. In Q-MI, CeMRI detects DE more frequently than perfusion defects and, especially, kinetic abnormalities are found by SPECT and Echo, respectively. CeMRI identifies small areas of DE also in some patients with nonQ-MI or RA but usually not in patients with EA. This biologically plausible decreasing trend is shown by CeMRI more clearly than by SPECT and Echo. Disagreement between CeMRI and SPECT or Echo may be reduced, but perhaps not fully eluded, performing dobutamine Echo and SPECT after maximal epicardial coronary dilatation.

Aged↗
PubMed2005

Contrast-enhanced magnetic resonance imaging assessment of scar size in patients with chronic myocardial infarction.

BACKGROUND: In the assessment of myocardial infarction (MI) mass, contrast-enhanced magnetic resonance imaging (CE-MRI) is comparable to single-photon emission computed tomography (SPECT). The aim of the present study was to determine whether the MI area, as assessed at CE-MRI and SPECT, is comparable to mass evaluation. We also compared CE-MRI and SPECT estimates of the MI area with functional evaluations made at echocardiography and kinetic MRI (cine-MRI). METHODS: We used a 1.0 Tesla MRI scanner and an inversion-recovery turboFLASH sequence, a tomographic gamma-camera and second-harmonic ultrasound systems. Two blinded operators assessed the extent of scarring, expressed as a percentage of the whole left ventricle (LV), using a 16-segment model. We studied 55 consecutive patients with a clinically stable healed MI (50 Q wave, 5 non-Q wave). RESULTS: The scar mass was 19+/-23% of the LV at CE-MRI and 21+/-25% at SPECT; the scar area was 29+/-23% of the LV at CE-MRI, 41+/-28% at SPECT, 29+/-31% at cine-MRI, and 32+/-29% at echocardiography. The Bland-Altman bias between CE-MRI and SPECT mass estimations was -2% of the LV with a+/-23% limit of agreement (LOA), while the bias between the area assessments was -12% with a+/-42% LOA. Bias between CE-MRI and functional evaluation by cine-MRI and echocardiography was 0% with a+/-39% LOA and -3% with a+/-36% LOA respectively. Comparing SPECT with cine-MRI and echocardiography the bias was 12% with a+/-52% LOA and 9% with a+/-56% LOA respectively. CONCLUSIONS: CE-MRI has proved to be comparable to SPECT in the assessment of the healed MI mass. Conversely, a high systematic error (high bias and LOA) renders CE-MRI and SPECT assessments of the MI area incomparable. Similarly (high bias and/or LOA) CE-MRI and SPECT estimations of the MI area cannot be compared with functional evaluation by echocardiography or cine-MRI.

Aged↗
PubMed2004

Prenatal ultrasound diagnosis of a case of Pfeiffer syndrome without cloverleaf skull and review of the literature.

Pfeiffer syndrome is characterized by bilateral coronal craniosynostosis, midface hypoplasia, beaked nasal tip, broad and medially deviated thumbs and great toes. Originally, it was described in eight persons from three generations in a pedigree consistent with an autosomal dominant transmission. Since then, several reports have documented its high clinical and genetic heterogeneity. The condition is usually detected in the newborn period or later, and very few prenatal ultrasound diagnoses have been reported. We present a case of Pfeiffer syndrome prenatally diagnosed at 20 weeks' gestation, in which the sonographic features of craniosynostosis, hypertelorism associated with an extreme proptosis, and broad thumb led to the diagnosis, confirmed after termination of pregnancy by dysmorphological, pathological and radiological evaluation. DNA analysis of the fibroblast growth factor receptor 2 (FGFR2) showed a missense mutation consisting in a transversion G --> C at nucleotide 870. This led to a Trp290Cys amino acidic substitution. We discuss the relevant findings of our and previously published cases. Our report demonstrates that a careful sonographic examination can lead to an early prenatal diagnosis of Pfeiffer syndrome also in cases without cloverleaf skull.

Abortion, Induced↗
PubMed2004

Non-invasive coronary angiography with multislice computed tomography. Technology, methods, preliminary experience and prospects.

The recent technical developments in multislice computed tomography (MSCT), with ECG retro-gated image reconstruction, have elicited great interest in the possibility of accurate non-invasive imaging of the coronary arteries. The latest generation of MSCT systems with 8-16 rows of detectors permits acquisition of the whole cardiac volume during a single 15-20 s breath-hold with a submillimetric definition of the images and an outstanding signal-to-noise ratio. Thus the race which, between MSCT, electron beam computed tomography and cardiac magnetic resonance imaging, can best provide routine and reliable imaging of the coronary arteries in clinical practice has recommenced. Currently available MSCT systems offer different options for both cardiac image acquisition and reconstruction, including multiplanar and curved multiplanar reconstruction, three-dimensional volume rendering, maximum intensity projection, and virtual angioscopy. In our preliminary experience including 176 patients suffering from known or suspected coronary artery disease, MSCT was feasible in 161 (91.5%) and showed a sensitivity of 80.4% and a specificity of 80.3%, with respect to standard coronary angiography, in detecting critical stenosis in coronary arteries and artery or venous bypass grafts. These results correspond to a positive predictive value of 58.6% and a negative predictive value of 92.2%. The true role that MSCT is likely to play in the future in non-invasive coronary imaging is still to be defined. Nevertheless, the huge amount of data obtainable by MSCT along with the rapid technological advances, shorter acquisition times and reconstruction algorithm developments will make the technique stronger, and possible applications are expected not only for non-invasive coronary angiography, but also for cardiac function and myocardial perfusion evaluation, as an all-in-one examination.

Artificial Intelligence↗
PubMed2003

Hb Trento: an elongated C-terminal beta chain due to a new frameshift mutation [beta144 (-A)].

An elongated C-terminal hemoglobin variant, due to the deletion of nucleotide A in codon 144 (nucleotide 63600 GenBank entry UO1317) was found in a 31-year-old woman from Trento (northeastern Italy). This deletion led to the replacement of lysine at beta144 by a serine residue, the disappearance of the stop codon at position 147, and the presence of 12 additional residues, identical to those observed in Hbs Saveme, Tak and Cranston, which result from a similar mechanism. Hb Trento, amounting to 29% of the total hemoglobin, was unstable and had, as the other variants of this group, an increased oxygen affinity. It led to a mild compensated hemolytic anemia with red cell inclusion bodies. Functional studies of the isolated abnormal hemoglobin were difficult to perform because of autoxidation, precipitation, and formation of hybrids with Hb A.

Adult↗
PubMed2002

[Non-invasive coronary angiography by multislice computed tomography: a new diagnostic method?].

A significant improvement in the noninvasive evaluation of coronary anatomy has been obtained after the introduction of the new high-speed multislice computed tomography systems. Images are reconstructed using retrospective ECG-gated protocol along with contrast analysis and three-dimensional display algorithms. The 8 detectors and the reduced tube rotation time of last-generation scanners allow the coverage of the entire heart during a single breath-hold following an intravenous bolus of 120 ml of nonionic contrast. Faster computer software offers submillimeter resolution reconstructions and increased post-processing capabilities, such as quantitative angiography, virtual angioscopy, and calcium score evaluation. At least in this phase of technical development the visualization of side branches of coronary vessels seems to advantage multislice computed tomography with respect to nuclear magnetic resonance and electron-beam computed tomography in the challenge for clinical noninvasive evaluation of coronary microcirculation.

Aged↗
PubMedDate not supplied

Retrorectal tumours: a case report.

The authors describe a case of retrorectal tumour in a 48-year-old female. Retrorectal tumours are rare, and their diagnosis is notoriously difficult and late. In this case the first-step diagnosis was made on the basis of clinical findings and radiological investigations such as abdominal ultrasonography. The second step included pelvic CT scans and MR imaging which yielded more precise anatomical details and information for the best surgical approach. We opted for a posterior approach with complete, easy removal of the tumour mass which, after pathological examination, turned out to be an epidermoid cyst. The postoperative course was uneventful and, one year after operation, the patient complains only of mild, irregular perineal pain with completely negative radiological investigations (US and CT scan).

Epidermal Cyst↗
PubMedDate not supplied

Imaging characteristics evaluation of a digital radiography system.

PURPOSE: To evaluate the physical imaging characteristics of an indirect digital radiography system used for general radiography. MATERIAL AND METHODS: The performance of the two 41x41 cm2 CsI:Tl/a-Si flat-panel detectors of a GE-Revolution XR/d digital radiography system was evaluated. Signal uniformity, dose linearity, pre-sampling and expectation Modulation Transfer Function (MTF), Noise Power Spectrum (NPS) and Detective Quantum Efficiency (DQE) were measured at 70 kVp, varying the incident dose levels, according to IEC 62220-1. The effects of anti-scatter grid on NPS were also studied. RESULTS: Both detectors have a limiting spatial resolution of 2.5 lp/mm set by the pixel pitch. Raw images demonstrated fairly good uniformity, excellent repeatability and linearity. Without the grid in the anode-cathode direction, for an 8 mGy incident dose, both pre-sampling and EMTF were greater than 0.5 and 0.2 for spatial frequencies of 1 and 2 lp/mm, respectively. At the same dose and frequencies, for one detector, DQE was greater than 0.61 and 0.20; for the other one, DQE was greater than 0.41 and 0.18. DISCUSSION AND CONCLUSIONS: The two detector panels showed different DQE curves. Namely, the table detector DQE was excellent at low dose levels but its performance appeared to degrade with increasing doses, both in mean values and in shape, whereas the wall stand detector DQE appeared to depend less strongly on dose. In any case, the DQE values obtained from this study were higher than those reported in the literature for storage phosphor Computed Radiography systems.

Humans↗