Arcadi T.,SDN IRCCS |
Maffei E.,Cardiovascular Imaging Unit |
Mantini C.,University of Chieti Pescara |
Guaricci A.I.,University of Foggia |
And 3 more authors.
Acta Biomedica | Year: 2015
Objectives: To compare image quality of iterative reconstruction algorithm(IRIS) vs. standard filtered back projection(FBP) reconstruction in CT Coronary Angiography (CTCA). Materials and methods: Thirty-four consecutive patients underwent CTCA for suspected or known CAD with Dual-Source CT (DSCT-Flash, Siemens). All datasets were reconstructed with 0.75/0.4 and 0.6/0.4 mm slice thickness/increment, using three standard FBP kernels (B26-B30-B46) and three comparable IRIS algorithms (I26-I30- I46). Vascular attenuation and noise were measured. CT vascular attenuation values [HU] were measured in: ascending aorta (Ao), right (RCA) and left (LCA) coronary artery, respectively. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratio were calculated. A p-value<0.05 was considered significant. Results: There was no significant difference between the vascular attenuation values measured with FBP (Ao:458HU, RCA:448HU, LAD:444HU) and IRIS (Ao:456HU, RCA:446HU, LAD:442HU). Difference in noise was significant between FBP (24±SD) and IRIS (19±SD) (r=0.34;p<0.05). Lowest noise was found for IRIS using 0.6 mm (17HU). IRIS provided a SNR and CNR significantly higher with increasing kernel sharpness. SNR was 33.3±25.1, 77.3±51.7, 37.2±36.6, 64.4±59.2, while CNR was 25.32±19.8, 58.0±36.0, 28.6±23.5, 47.6±47.3 for 0.75B, 0.75I, 0.6B and 0.6I, respectively. IRIS showed an improvement in SNR of 57% and 56% for 0.75 mm and 0.6 mm, respectively, and an improvement in CNR of 42% and 40% for 0.75 mm and 0.6 mm. Conclusions: In CTCA, iterative reconstructions provide a significant higher image quality compared with the conventional FBP reconstructions. © Mattioli 1885. Source
Maffei E.,Vascular Imaging |
Arcadi T.,Vascular Imaging |
Zuccarelli A.,Ospedale Di Carrara |
Clemente A.,Vascular Imaging |
And 6 more authors.
Journal of Cardiovascular Medicine | Year: 2013
Aim The aim of this study is to assess the image quality and diagnostic accuracy of computed tomography (CT) coronary angiography (CTCA) in different hospital settings with the same trained team. Materials and methods Four hundred patients were consecutively enrolled for CTCA in a large academic hospital (Group 1; Sensation 64 Cardiac, Siemens - Iomeprol 400, Bracco; 200 patients) and in a small local hospital (Group 2; VCT, GE Healthcare - Iodixanol 320, GE Healthcare; 200 patients). All patients were enrolled for suspected coronary artery disease (CAD) and patients with stents or who had previously undergone coronary bypass were excluded. Scan protocols (retrospectively ECG-gated; no dose reduction modulation applied) were performed in accordance with standards reported in the international literature with the best solution available on site. Image quality was assessed in each coronary segment with a 4-point Likert scale: 0, not assessable; 1, low; 2, average; 3, good. Diagnostic accuracy was calculated against conventional coronary angiography with a threshold of at least 50% for significant stenosis. Results There was no significant difference between demographics, BMI, prevalence of obstructive CAD, calcium score and heart rate between the two populations. The average image quality was 2.83W0.37 for Group 1 and 2.86W0.31 for Group 2 (P>0.05). Per-segment sensitivity, specificity, positive and negative predictive values were 92.6% (87-95), 97.9% (97-98), 75.9% (69-81) and 99.5% (99-99), respectively, for Group 1, and 90.4% (85-93), 98.6% (98-99), 84.2% (78-88) and 99.2% (98-99), respectively, for Group 2 (P>0.05). Conclusion There is no significant difference in image quality and diagnostic accuracy of CTCA when the investigation is performed by the same properly trained team. CTCA is a robust imaging modality for the detection of coronary artery stenosis. Source
Anzilotti S.,SDN IRCCS |
Tornincasa M.,University of Naples Federico II |
Gerlini R.,University of Naples Federico II |
Conte A.,University of Naples Federico II |
And 8 more authors.
Cell Death and Disease | Year: 2015
Homeodomain-interacting protein kinase 2 (HIPK2) is a multitalented coregulator of an increasing number of transcription factors and cofactors involved in cell death and proliferation in several organs and systems. As Hipk2 - mice show behavioral abnormalities consistent with cerebellar dysfunction, we investigated whether Hipk2 is involved in these neurological symptoms. To this aim, we characterized the postnatal developmental expression profile of Hipk2 in the brain cortex, hippocampus, striatum, and cerebellum of mice by real-time PCR, western blot analysis, and immunohistochemistry. Notably, we found that whereas in the brain cortex, hippocampus, and striatum, HIPK2 expression progressively decreased with age, that is, from postnatal day 1 to adulthood, it increased in the cerebellum. Interestingly, mice lacking Hipk2 displayed atrophic lobules and a visibly smaller cerebellum than did wild-type mice. More important, the cerebellum of Hipk2 - mice showed a strong reduction in cerebellar Purkinje neurons during adulthood. Such reduction is due to the activation of an apoptotic process associated with a compromised proteasomal function followed by an unpredicted accumulation of ubiquitinated proteins. In particular, Purkinje cell dysfunction was characterized by a strong accumulation of ubiquitinated β-catenin. Moreover, our behavioral tests showed that Hipk2 - mice displayed muscle and balance impairment, indicative of Hipk2 involvement in cerebellar function. Taken together, these results indicate that Hipk2 exerts a relevant role in the survival of cerebellar Purkinje cells and that Hipk2 genetic ablation generates cerebellar dysfunction compatible with an ataxic-like phenotype. © 2015 Macmillan Publishers Limited All rights reserved. Source
Catalano O.A.,Parthenope University of Naples |
Nicolai E.,SDN IRCCS |
Rosen B.R.,Massachusetts General Hospital |
Luongo A.,University of Naples Federico II |
And 7 more authors.
British Journal of Cancer | Year: 2015
Background:Despite improvements in treatments, metastatic breast cancer remains difficult to cure. Bones constitute the most common site of first-time recurrence, occurring in 40-75% of cases. Therefore, evaluation for possible osseous metastases is crucial. Technetium 99 (99 Tc) bone scintigraphy and fluorodexossyglucose (FDG) positron emission tomography (PET)-computed tomography (PET-CT) are the most commonly used techniques to assess osseous metastasis. PET magnetic resonance (PET-MR) imaging is an innovative technique still under investigation. We compared the capability of PET-MR to that of same-day PET-CT to assess osseous metastases in patients with breast cancer.Methods:One hundred and nine patients with breast cancer, who underwent same-day contrast enhanced (CE)-PET-CT and CE-PET-MR, were evaluated. CE-PET-CT and CE-PET-MR studies were interpreted by consensus by a radiologist and a nuclear medicine physician. Correlations with prior imaging and follow-up studies were used as the reference standard. Binomial confidence intervals and a χ 2 test were used for categorical data, and paired t-test was used for the SUVmax data; a non-informative prior Bayesian approach was used to estimate and compare the specificities.Results:Osseous metastases affected 25 out 109 patients. Metastases were demonstrated by CE-PET-CT in 22 out of 25 patients (88%±7%), and by CE-PET-MR in 25 out of 25 patients (100%). CE-PET-CT revealed 90 osseous metastases and CE-PET-MR revealed 141 osseous metastases (P<0.001). The estimated sensitivity of CE-PET-CT and CE-PET-MR were 0.8519 and 0.9630, respectively. The estimated specificity for CE-FDG-PET-MR was 0.9884. The specificity of CE-PET-CT cannot be determined from patient-level data, because CE-PET-CT yielded a false-positive lesion in a patient who also had other, true metastases.Conclusions:CE-PET-MR detected a higher number of osseous metastases than did same-day CE-PET-CT, and was positive for 12% of the patients deemed osseous metastasis-negative on the basis of CE-PET-CT. © 2015 Cancer Research UK. Source
Cuomo O.,University of Naples Federico II |
Pignataro G.,University of Naples Federico II |
Sirabella R.,SDN IRCCS |
Molinaro P.,University of Naples Federico II |
And 5 more authors.
Stroke | Year: 2016
Background and Purpose-The small ubiquitin-like modifier (SUMO), a ubiquitin-like protein involved in posttranslational protein modifications, is activated by several conditions, such as heat stress, hypoxia, and hibernation and confers neuroprotection. Sumoylation enzymes and substrates are expressed also at the plasma membrane level. Among the numerous plasma membrane proteins controlling ionic homeostasis during cerebral ischemia, 1 of the 3 brain sodium/calcium exchangers (NCX3), exerts a protective role during ischemic preconditioning. In this study, we evaluated whether NCX3 is a target for sumoylation and whether this posttranslational modification participates in ischemic preconditioning-induced neuroprotection. To test these hypotheses, we analyzed (1) SUMO1 conjugation pattern after ischemic preconditioning; (2) the effect of SUMO1 knockdown on the ischemic damage after transient middle cerebral artery occlusion and ischemic preconditioning, (3) the possible interaction between SUMO1 and NCX3 and (4) the molecular determinants of NCX3 sequence responsible for sumoylation. Methods-Focal brain ischemia and ischemic preconditioning were induced in rats by middle cerebral artery occlusion. SUMOylation was evaluated by western blot and immunohistochemistry. SUMO1 and NCX3 interaction was analyzed by site-directed mutagenesis and immunoprecipitation assay. Results-We found that (1) SUMO1 knockdown worsened ischemic damage and reduced the protective effect of preconditioning; (2) SUMO1 bound to NCX3 at lysine residue 590, and its silencing increased NCX3 degradation; and (3) NCX3 sumoylation participates in SUMO1 protective role during ischemic preconditioning. Thus, our results demonstrate that NCX3 sumoylation confers additional neuroprotection in ischemic preconditioning. Conclusions-Finally, this study suggests that NCX3 sumoylation might be a new target to enhance ischemic preconditioninginduced neuroprotection. © 2016 American Heart Association, Inc. Source