20 results on '"Maresi E."'
Search Results
2. Iperplasia midollare surrenale nei tossicodipendenti
- Author
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Perrone G, Bilotta C, Guajana A, Baldino G, Randisi F, Mondello C, Ventura Spagnolo E, Zerbo S, Argo A, Maresi e, Perrone G, Bilotta C, Guajana A, Baldino G, Randisi F, Mondello C, Ventura Spagnolo E, Zerbo S, Argo A, and Maresi e
- Subjects
Tossicodipendenti - Published
- 2019
3. PS1295 IRON IN THE HUMAN HEARTS: DISTRIBUTION AND ASSOCIATION WITH R2∗ VALUES BY CMR
- Author
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Meloni, A., primary, Maggio, A., additional, Positano, V., additional, Angelini, A., additional, Putti, M.C., additional, Maresi, E., additional, Pucci, A., additional, Basso, C., additional, Leto, F., additional, Perazzolo, M., additional, Pistoia, L., additional, and Pepe, A., additional
- Published
- 2019
- Full Text
- View/download PDF
4. Fatal complication of sickle cell anemia in an immigrant patient rescued from the mediterranean sea.
- Author
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Alongi, A., Spagnolo, E. Ventura, Zerbo, S., Aronica, G. L., Korte, F., Maresi, E., and Argo, A.
- Subjects
SICKLE cell anemia ,IMMIGRANTS ,BRONCHOPNEUMONIA ,PULMONARY embolism - Abstract
The aim of this case report is to share with the forensic science community the experience of a rare complication of sickle cell anemia: acute chest syndrome. In October 2016, at the port of the city of Trapani (Sicily, Italy), the landing of an ONG "Médecins Sans Frontières" ship took place with 548 non-EU citizens and a corpse on board. The man, in the hours before his death, complained of severe chest pain and respiratory difficulties, and, despite of the therapeutic aids and resuscitation maneuvers, lastly died. The Public Prosecutor ordered that autopsy be executed on the corpse of the young Ghanaian, and it was to be supplemented by histological, toxicological, genetic investigations, and the dating of the biological age. The autoptic examination findings were indicative of bilateral bronchopneumonia, and were also confirmed by the histological findings, which identified a condition of massive adipose pulmonary embolism, due to the presence of extramedullary hematopoietic tissue, site of endovascular thrombosis secondary to hemolysis of sickle cells. The spleen appeared of small volume, with fibrotic phenomena. The predisposition to infections, thrombosis, extramedullary hematopoiesis are all complications of sickle cell anemia. The severe pulmonary condition characterized by vaso-occlusive findings and pulmonary inflammation with infiltrate, symptoms like fever, chest pain and severe systemic hypoxia allowed to ascribe the plausible cause of death as acute chest syndrome, a rare complication of sickle cell anemia. The peculiarity of this clinical case is also related to the methods of medical intervention (boat with non-governmental medical support for assistance to migrants). [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
5. Case Report: Unusual Clinical Presentation of a Rare Cardiac Inflammatory Myofibroblastic Tumor in Children: The Differential Diagnosis With Pediatric Emergencies
- Author
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Stefania Zerbo, Antonina Argo, Ettore Piro, Giovanni De Lisi, Pietro Di Pasquale, Emiliano Maresi, Giulio Perrone, Clio Bilotta, Bilotta C., Perrone G., Maresi E., De Lisi G., Di Pasquale P., Piro E., Argo A., and Zerbo S.
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Astrocytoma ,Case Report ,Magnetic resonance imaging ,Neurological examination ,heart ,Cardiac Inflammatory Myofibroblastic Tumor ,Rhabdomyoma ,Children, Heart, Immunohistochemical investigations, Inflammatory myofibroblastic tumor, Rare tumor ,medicine.disease ,Pediatrics ,RJ1-570 ,children ,Pediatrics, Perinatology and Child Health ,rare tumor ,medicine ,inflammatory myofibroblastic tumor ,immunohistochemical investigations ,Sarcoma ,Radiology ,Fibroma ,Differential diagnosis ,business - Abstract
Introduction: There are still no guidelines about pediatric cardiac cancers. The purpose of this work is to provide new scientific data facilitating the differential diagnosis of a rare cardiac tumor with an unusual presentation, such as the cardiac inflammatory myofibroblastic tumor (IMT).Case Presentation: A 3-year-old male child presented with several symptoms including unconsciousness, vomiting, and drowsiness. A clinical and neurological examination revealed a unilateral (right) motor delay and positive unilateral Babinski sign. Electrocardiogram (ECG) was normal.Diagnostic Assessment: The total body computed tomography (CT) scans showed hypodensity in the left temporal–parietal lobe, a large hypodense area in the right frontal lobe, and a second area in the left frontal lobe were found with head CT. A magnetic resonance (MR) also noted cerebral areas of hypointensity. The echocardiographic images revealed an ovoid mass, adherent to the anterolateral papillary muscle. The histological exams, performed with hematoxylin–eosin, Masson's trichrome, Alcian blue PAS, Weigert and Van-Gieson stain, allowed observing the microscopic structure of the neoplastic mass. The immunohistochemical analysis was performed through subsequent antibodies: anti-vimentin, anti-actina, anti-ALK, anti-CD8, anti-CD3, anti-CD20, anti-kappa and lambda chains, and anti CD68 antibodies. The healthcare professionals diagnosed a cardiac IMT with brain embolism.Differential Diagnosis: The ventricular localization, observed through radiological exams, required a differential diagnosis with fibroma and rhabdomyoma, the presence of brain embolism with sarcoma, and its morphology with fibroma. Neurological symptoms might be attributed to encephalitis, primitive cerebral cancer, such as astrocytoma or neuroblastoma, cerebral metastases due to any malignancy, or embolic stroke.Conclusion: New studies are encouraged to better define IMT behavior and draw up guidelines confirming the crucial role of multidisciplinary approach and treatment protocol selected on the basis of the characteristics of the tumors, in the case of this rare type of cancer.
- Published
- 2021
- Full Text
- View/download PDF
6. Fatal complication of sickle cell anemia in an immigrant patient rescued from the mediterranean sea
- Author
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A, Alongi, E, Ventura Spagnolo, S, Zerbo, G L, Aronica, F, Korte, E, Maresi, A, Argo, Alongi A., Ventura Spagnolo E., Zerbo S., Aronica G.L., Korte F., Maresi E., and Argo A.
- Subjects
Male ,Chest Pain ,Fever ,Migrant ,Emigrants and Immigrants ,Anemia, Sickle Cell ,Ghana ,Death ,Dyspnea ,Rescue ,Acute chest syndrome ,Sickle cell anemia ,Mediterranean Sea ,Humans ,Sicily - Abstract
The aim of this case report is to share with the forensic science community the experience of a rare complication of sickle cell anemia: acute chest syndrome. In October 2016, at the port of the city of Trapani (Sicily, Italy), the landing of an ONG "Médecins Sans Frontières" ship took place with 548 non-EU citizens and a corpse on board. The man, in the hours before his death, complained of severe chest pain and respiratory difficulties, and, despite of the therapeutic aids and resuscitation maneuvers, lastly died. The Public Prosecutor ordered that autopsy be executed on the corpse of the young Ghanaian, and it was to be supplemented by histological, toxicological, genetic investigations, and the dating of the biological age. The autoptic examination findings were indicative of bilateral bronchopneumonia, and were also confirmed by the histological findings, which identified a condition of massive adipose pulmonary embolism, due to the presence of extramedullary hematopoietic tissue, site of endovascular thrombosis secondary to hemolysis of sickle cells. The spleen appeared of small volume, with fibrotic phenomena. The predisposition to infections, thrombosis, extramedullary hematopoiesis are all complications of sickle cell anemia. The severe pulmonary condition characterized by vaso-occlusive findings and pulmonary inflammation with infiltrate, symptoms like fever, chest pain and severe systemic hypoxia allowed to ascribe the plausible cause of death as acute chest syndrome, a rare complication of sickle cell anemia. The peculiarity of this clinical case is also related to the methods of medical intervention (boat with non-governmental medical support for assistance to migrants).
- Published
- 2020
7. Post-mortem Foetal Imaging
- Author
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Roberto Lagalla, Sergio Salerno, Giuseppe Lo Re, Emiliano Maresi, Filippo Alberghina, Maria Chiara Terranova, Salerno S., Alberghina F., Terranova M.C., Lo Re G., Maresi E., and Lagalla R.
- Subjects
medicine.medical_specialty ,business.industry ,Radiological weapon ,Autopsy examination ,Foetal death ,Medicine ,Autopsy ,Gold standard (test) ,Radiology ,business ,CT ,MRI ,Post-mortem foetal imaging - Abstract
The gold standard for the diagnosis of foetal death is known to be the autopsy examination, which is sometimes supplemented by chromosomal and/or genetic studies. Nevertheless, autopsy rates are continuously declining, due to multifactorial and complex reasons, even anatomical, social and psychological ones, thus impacting the rate of radiological post-mortem foetal examinations.
- Published
- 2019
- Full Text
- View/download PDF
8. Utility of post mortem MRI in definition of thrombus in aneurismatic coronary arteries due to incomplete Kawasaki Disease in infants
- Author
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Massimo Midiri, Emiliano Maresi, C Sortino, Emanuele Grassedonio, Antonina Argo, A Rizzo, Stefania Zerbo, Argo, A., Zerbo, S., Maresi, E., Rizzo, A., Sortino, C., Grassedonio, E., and Midiri, M.
- Subjects
medicine.medical_specialty ,Radiology, Nuclear Medicine and Imaging ,Aneurismatic coronary arterie ,Autopsy ,030204 cardiovascular system & hematology ,030218 nuclear medicine & medical imaging ,Pathology and Forensic Medicine ,Forensic pathology ,03 medical and health sciences ,0302 clinical medicine ,Aneurysm ,Incomplete Kawasaki disease ,Internal medicine ,medicine ,Post-mortem MRI ,Thrombus ,business.industry ,medicine.disease ,Thrombosis ,Coronary arteries ,Stenosis ,medicine.anatomical_structure ,Sudden infant death ,Thrombosi ,Cardiology ,Kawasaki disease ,business ,Vasculitis - Abstract
Kawasaki disease (KD) is an acute, self-limited vasculitis of unknown etiology that primarily affects the coronary artery (CA) and presents in childhood. The characteristic coronary arterial lesion is an aneurysm, which may lead to thrombosis, dilatation, stenosis, and occlusion. Such an aneurysm is typically calcified and generally develops five or more years after the onset of acute KD. It becomes more noticeable after ten years. KD is sometimes difficult to diagnose because of the limited clinical features, especially in infants younger than 6 months old, where the clinical presentations often do not fulfill the diagnostic criteria for KD. We report a case of Incomplete Kawasaki Disease (IKD) causing unexpected death in infants. A seven-month-old male baby, apparently well nourished and without fever or exanthema that was unexpectedly found agonal in his bed by his parents. He died in an emergency room a few hours later in spite of aggressive resuscitation efforts. Postmortem Magnetic Resonance Images were obtained during the autopsy, with evidence of an occlusive thrombus in left and right coronary artery aneurysms. Laboratory findings were consistent with IKD. The crucial role of postmortem imaging is discussed here in order to improve diagnosis tools for preventable events.
- Published
- 2016
9. Asthmatic bronchial lesions in drug addicted
- Author
-
MARESI, Emiliano, LANZARONE, Antonietta, ZERBO, Stefania, VENTURA SPAGNOLO, Elvira, SORTINO, Cettina, GIANNONE, Antonino Giulio, ARGO, Antonina, Maresi, E., Lanzarone, A., Zerbo, S., Ventura Spagnolo, E., Sortino, C., Giannone, A., and Argo, A.
- Subjects
drug abuse, bronchial asthma, goblet cell metaplasia - Published
- 2016
10. Delayed Traumatic Rupture of the Spleen in a Patient with Mantle Cell Non-Hodgkin Lymphoma after an In-Hospital Fall: A Fatal Case.
- Author
-
Albano GD, Zerbo S, Spanò M, Grassi N, Maresi E, Florena AM, and Argo A
- Abstract
Splenic rupture and hematoma are significant complications that can occur in patients with non-Hodgkin lymphoma (NHL). Understanding these associated complications is essential for optimal patient management and enhanced patient outcomes. Histopathological and immunohistochemical analyses are crucial in diagnosing NHL and assessing splenic involvement. In this study, a judicial autopsy had been requested by the Prosecutor's Office for a malpractice claim due to a fall in the hospital. In the Emergency Department, a 72-year-old man fell from a gurney and reported sustaining a wound to his forehead. No other symptoms were reported. A face and brain CT scan showed no abnormalities. Nine days after discharge, the patient presented with abdominal pain. An abdominal CT revealed splenic rupture and hemoperitoneum. The patient underwent open splenectomy but showed signs of hemodynamic shock and subsequently died. The evidence from the autopsy allowed us to diagnose mantle cell non-Hodgkin lymphoma with spleen involvement, previously unknown. Histopathological and immunohistochemical analyses were performed to assess the diagnosis of splenic rupture and estimate its timing. The findings strongly suggest that the splenic rupture was associated with the patient's fall and the pre-existing malignancy. This case highlights the importance of considering an underlying hematological malignancy when investigating delayed splenic rupture. An immunohistochemical study of spleen samples allowed the timing of splenic hematoma and rupture to be assessed, leading to the establishment of a causal relationship with trauma.
- Published
- 2024
- Full Text
- View/download PDF
11. Useless and limits of Postmortem CT (PMCT) in a complex case of preterm infant murder.
- Author
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Viola I, Terranova MC, Lo Re G, De Lisi G, Serra G, Maresi E, and Salerno S
- Subjects
- Infant, Female, Humans, Infant, Newborn, Autopsy methods, Forensic Pathology methods, Homicide, Infant, Premature, Tomography, X-Ray Computed methods
- Abstract
The present case-report empathizes the usefulness of post-mortem computed tomography (PMCT) in the detection of live birth signs in a baby found dead, comparing the results with standard autoptic, histologic and immunohistochemical examinations. The report describes the case of a new-born who was thrown out on the footpath from a window of the fifth floor according to the investigative police, whilst the mother has hidden herself immediately after childbirth. PMCT showed diffusely aerated lung parenchyma with signs of severe lung distress, air in the airways with no fluid inside, and air in the upper gastro-intestinal tract, in absence any resuscitation manoeuvres performed on the baby at delivery. PMCT underlined multiple fractures of the skull with degeneration of cerebral parenchyma. All these findings were confirmed by conventional autopsy and histological and immunohistochemical examinations, clinching the usefulness of PMCT in differentiating live births from stillbirths., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
12. Juvenile sudden cardiac death due to congenital coronary ostial valve-like ridges: A case report and literature review.
- Author
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Albano GD, Scalzo G, Malta G, De Lisi G, Argo A, Maresi E, and Zerbo S
- Abstract
Coronary artery anomalies are a heterogeneous group of congenital disorders affecting the coronary pattern with a characteristic (origin, number, number of hosts, course, etc.). They are rarely found in the population. We report the case of a 21-year-old male who died from sudden cardiac death caused by an isolated coronary ostial obstruction, secondary to a rare anomaly, the presence of a valve-like ridge consisting of a small fold in the Valsalva aortic sinus. The study provides a brief literature review on the pathophysiology, diagnosis, and clinical and medico-legal issues in coronary artery anomaly cases that may be helpful in forensic practice when dealing with sudden cardiac death in young people and highlights key points for further research and public health measures.
- Published
- 2023
- Full Text
- View/download PDF
13. Challenges in gene-oriented approaches for pangenome content discovery.
- Author
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Bonnici V, Maresi E, and Giugno R
- Subjects
- Bacteria classification, Bacteria genetics, Biological Evolution, Mycoplasma classification, Mycoplasma genetics, Phylogeny, Software, Algorithms, Computational Biology methods, Genome genetics, Genome, Bacterial genetics, Genomics methods
- Abstract
Given a group of genomes, represented as the sets of genes that belong to them, the discovery of the pangenomic content is based on the search of genetic homology among the genes for clustering them into families. Thus, pangenomic analyses investigate the membership of the families to the given genomes. This approach is referred to as the gene-oriented approach in contrast to other definitions of the problem that takes into account different genomic features. In the past years, several tools have been developed to discover and analyse pangenomic contents. Because of the hardness of the problem, each tool applies a different strategy for discovering the pangenomic content. This results in a differentiation of the performance of each tool that depends on the composition of the input genomes. This review reports the main analysis instruments provided by the current state of the art tools for the discovery of pangenomic contents. Moreover, unlike previous works, the presented study compares pangenomic tools from a methodological perspective, analysing the causes that lead a given methodology to outperform other tools. The analysis is performed by taking into account different bacterial populations, which are synthetically generated by changing evolutionary parameters. The benchmarks used to compare the pangenomic tools, in addition to the computational pipeline developed for this purpose, are available at https://github.com/InfOmics/pangenes-review. Contact: V. Bonnici, R. Giugno Supplementary information: Supplementary data are available at Briefings in Bioinformatics online., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
- Full Text
- View/download PDF
14. Cardiovascular Implantable Electronic Device Infection and New Insights About Correlation Between Pro-inflammatory Markers and Heart Failure: A Systematic Literature Review and Meta-Analysis.
- Author
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Zerbo S, Perrone G, Bilotta C, Adelfio V, Malta G, Di Pasquale P, Maresi E, and Argo A
- Abstract
Introduction: Surgical approaches to treat patients with abnormal pro-inflammatory parameters remain controversial, and the debate on the correlation between hematological parameter alteration in cardiac implantable electronic device (CIED) infection and the increase in mortality continues. Methods: We performed a systematic review using the PubMed, Scopus, and Cochrane Library databases. Twenty-two articles from May 2007 to April 2020 were selected and divided according to the following topics: prevalence of microbes in patients with CIED infection; characteristics of patients with CIED infection; comparison between patients who underwent and did not undergo replantation after device extraction; and correlation between alteration of hematological parameters and poor prognosis analysis. Results: Epidemiological analysis confirmed high prevalence of male sex, staphylococcal infection, and coagulase-negative staphylococci (CoNS). The most common comorbidity was heart failure. Complete removal of CIED and antimicrobial therapy combination are the gold standard. CIED replacement was associated with higher survival. High preoperative white blood cell count and C-reactive protein levels increased the risk of right ventricular failure (RVF) development. Increased red blood cell distribution width (RDW) value or decreased platelet count was correlated with poor prognosis. No correlation was noted between preoperative leukocytosis and CIED infection. Discussion: A relevant correlation between leukocytosis and RVF was observed. Heart failure may be related to high RDW values and decreased platelet count. Data on the correlation between hematological parameter alteration and poor prognosis are missing in many studies because of delayed implantation in patients showing signs of infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zerbo, Perrone, Bilotta, Adelfio, Malta, Di Pasquale, Maresi and Argo.)
- Published
- 2021
- Full Text
- View/download PDF
15. Fatal complication of sickle cell anemia in an immigrant patient rescued from the mediterranean sea.
- Author
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Alongi A, Ventura Spagnolo E, Zerbo S, Aronica GL, Korte F, Maresi E, and Argo A
- Subjects
- Anemia, Sickle Cell complications, Anemia, Sickle Cell diagnosis, Chest Pain etiology, Dyspnea etiology, Fever etiology, Ghana ethnology, Humans, Male, Mediterranean Sea, Sicily, Anemia, Sickle Cell mortality, Emigrants and Immigrants
- Abstract
The aim of this case report is to share with the forensic science community the experience of a rare complication of sickle cell anemia: acute chest syndrome. In October 2016, at the port of the city of Trapani (Sicily, Italy), the landing of an ONG "Médecins Sans Frontières" ship took place with 548 non-EU citizens and a corpse on board. The man, in the hours before his death, complained of severe chest pain and respiratory difficulties, and, despite of the therapeutic aids and resuscitation maneuvers, lastly died. The Public Prosecutor ordered that autopsy be executed on the corpse of the young Ghanaian, and it was to be supplemented by histological, toxicological, genetic investigations, and the dating of the biological age. The autoptic examination findings were indicative of bilateral bronchopneumonia, and were also confirmed by the histological findings, which identified a condition of massive adipose pulmonary embolism, due to the presence of extramedullary hematopoietic tissue, site of endovascular thrombosis secondary to hemolysis of sickle cells. The spleen appeared of small volume, with fibrotic phenomena. The predisposition to infections, thrombosis, extramedullary hematopoiesis are all complications of sickle cell anemia. The severe pulmonary condition characterized by vaso-occlusive findings and pulmonary inflammation with infiltrate, symptoms like fever, chest pain and severe systemic hypoxia allowed to ascribe the plausible cause of death as acute chest syndrome, a rare complication of sickle cell anemia. The peculiarity of this clinical case is also related to the methods of medical intervention (boat with non-governmental medical support for assistance to migrants).
- Published
- 2020
- Full Text
- View/download PDF
16. CMR for myocardial iron overload quantification: calibration curve from the MIOT Network.
- Author
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Meloni A, Maggio A, Positano V, Leto F, Angelini A, Putti MC, Maresi E, Pucci A, Basso C, Marra MP, Pistoia L, De Marchi D, and Pepe A
- Subjects
- Calibration, Humans, Iron Overload etiology, beta-Thalassemia complications, Iron analysis, Iron Overload diagnosis, Magnetic Resonance Spectroscopy methods, Myocardium chemistry
- Abstract
Objectives: R2* cardiac magnetic resonance (CMR) allows the non-invasive measurement of myocardial iron. We calibrated cardiac R2* values against myocardial tissue-measured iron concentration by using a segmental approach and we assessed the iron distribution., Methods: Five hearts of thalassemia patients were donated after death/transplantation to the CoreLab of the Myocardial Iron Overload in Thalassemia Network. A multislice multiecho R2* approach was adopted. After CMR, used as guidance, the heart was cut in three short-axis slices and each slice was cut into different equiangular segments according to AHA segmentation and differentiated into endocardial and epicardial layers. Tissue iron concentration was measured by atomic absorption spectrometer technique., Results: Fifty-five samples were used since only for two hearts all the 16 samples were analyzed. Mean iron concentration was 4.71 ± 4.67 mg/g dw. Segmental iron levels ranged from 0.24 to 13.78 mg/g dw. The coefficient of variability of iron for myocardial segments ranged from 8.08 to 24.54% (mean 13.49 ± 6.93%). Iron concentration was significantly higher in the epicardial than in the endocardial layer (5.99 ± 6.01 vs 4.84 ± 4.87 mg/g dw; p = 0.042). Four different circumferential regions (anterior, septal, inferior, and lateral) were defined. A circumferential heterogeneity was noted, with more iron in the anterior region, followed by the inferior region. The direct nonlinear fitting of R2* and [Fe] data led to the calibration curve: [Fe] = 0.0022 ∙ (R2*-ROI)
1.462 (R-square = 0.956)., Conclusions: Our data further validate R2* CMR using a segmental approach as a sensitive and early technique for quantifying iron distribution in the current clinical practice., Key Points: • Calibration in humans for cardiovascular magnetic resonance R2* against myocardial iron concentration was provided. • A circumferential heterogeneity in cardiac iron distribution was detected: more iron was observed in the anterior region, followed by the inferior region. This finding corroborates the use of a segmental T2* CMR approach in the clinical practice to detect a heterogeneous iron distribution. • The comparison between the cardiac T2* values obtained with the region-based and the pixel-wise approaches showed a significant correlation and no significant difference but, in presence of significant iron load, the region-based approach resulted in significantly higher T2* values.- Published
- 2020
- Full Text
- View/download PDF
17. Functional Characterization and Structure-Guided Mutational Analysis of the Transsulfuration Enzyme Cystathionine γ-Lyase from Toxoplasma gondii .
- Author
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Maresi E, Janson G, Fruncillo S, Paiardini A, Vallone R, Dominici P, and Astegno A
- Subjects
- Cystathionine, Phosphoric Monoester Hydrolases genetics, Phosphoric Monoester Hydrolases metabolism, Toxoplasma genetics, Toxoplasma metabolism, Cystathionine gamma-Lyase genetics, Cystathionine gamma-Lyase metabolism, DNA Mutational Analysis methods, Mutation genetics, Toxoplasma enzymology
- Abstract
Sulfur-containing amino acids play essential roles in many organisms. The protozoan parasite Toxoplasma gondii includes the genes for cystathionine β-synthase and cystathionine γ-lyase (TgCGL), as well as for cysteine synthase, which are crucial enzymes of the transsulfuration and de novo pathways for cysteine biosynthesis, respectively. These enzymes are specifically expressed in the oocyst stage of T. gondii . However, their functionality has not been investigated. Herein, we expressed and characterized the putative CGL from T. gondii . Recombinant TgCGL almost exclusively catalyses the α,γ-hydrolysis of l-cystathionine to form l-cysteine and displays marginal reactivity toward l-cysteine. Structure-guided homology modelling revealed two striking amino acid differences between the human and parasite CGL active-sites (Glu59 and Ser340 in human to Ser77 and Asn360 in toxoplasma). Mutation of Asn360 to Ser demonstrated the importance of this residue in modulating the specificity for the catalysis of α,β- versus α,γ-elimination of l-cystathionine. Replacement of Ser77 by Glu completely abolished activity towards l-cystathionine. Our results suggest that CGL is an important functional enzyme in T. gondii , likely implying that the reverse transsulfuration pathway is operative in the parasite; we also probed the roles of active-site architecture and substrate binding conformations as determinants of reaction specificity in transsulfuration enzymes.
- Published
- 2018
- Full Text
- View/download PDF
18. Early structural degeneration of Mitroflow aortic valve: another issue in addition to the mismatch?
- Author
-
Ruvolo G, Pisano C, Balistreri CR, Maresi E, Triolo OF, Argano V, Bassano C, Vacirca SR, Nardi P, and Orlandi A
- Abstract
We reported two cases of early structural valve degeneration (SVD) with Mitroflow prosthesis in aortic position in patients above the age of 65 years. Microscopic aspects have been analysed to investigate the intrinsic mechanism of SVD. New techniques to improve the structure and the preservation of this prosthesis are needed in order to reduce potential dangerous early complications., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.
- Published
- 2018
- Full Text
- View/download PDF
19. When a death apparently associated to sexual assault is instead a natural death due to idiopathic hypereosinophilic syndrome: The importance of gamma-hydroxybutyric acid analysis in vitreous humor.
- Author
-
Busardò FP, Portelli F, Montana A, Rotolo MC, Pichini S, and Maresi E
- Subjects
- Female, Forensic Medicine, Humans, Italy, Vitreous Body, Young Adult, Autopsy, Hydroxybutyrates isolation & purification, Hypereosinophilic Syndrome, Rape
- Abstract
We here report a case involving a 21-year-old female, found dead in a central square of a city in the south of Italy. Initial evidences and circumstances were suggestive of a death associated with a sexual assault. Two peripheral blood and two vitreous humor samples were collected for the purpose of gamma-hydroxybutyric acid (GHB) testing from the dead body at two different post-mortem intervals (PMIs): approximately 2 (t
0 ) and 36 (t1 ) hours. The obtained results showed that, between t0 and t1, there was an increase of GHB concentrations in peripheral blood and vitreous humor of 66.3% and 8.1%, respectively. This case was the first evidence of GHB post mortem production in a dead body and not in vitro, showing that vitreous humor is less affected than peripheral blood in GHB post-mortem production. The value detected at t1 in peripheral blood (53.4µg/mL) exceeded the proposed cut-off and if interpreted alone would have led to erroneous conclusions. This was not the case of vitreous humor GHB, whose post-mortem increase was minimal and it allowed to exclude a GHB exposure. Only after a broad forensic investigation including a complete autopsy, serological, histological, toxicological and haematology analyses, a diagnosis of idiopathic hypereosinophilic syndrome, a myeloproliferative disorder characterized by persistent eosinophilia associated with damage to multiple organs, was made and the cause of death was due to a pulmonary eosinophilic vasculitis responsible for an acute respiratory failure., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2017
- Full Text
- View/download PDF
20. Unique substrate specificity of ornithine aminotransferase from Toxoplasma gondii .
- Author
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Astegno A, Maresi E, Bertoldi M, La Verde V, Paiardini A, and Dominici P
- Subjects
- Amino Acid Sequence, Catalytic Domain, Cloning, Molecular, Escherichia coli genetics, Escherichia coli metabolism, Gene Expression, Humans, Kinetics, Models, Molecular, Ornithine metabolism, Ornithine-Oxo-Acid Transaminase genetics, Ornithine-Oxo-Acid Transaminase metabolism, Protein Binding, Protein Domains, Protein Structure, Secondary, Protozoan Proteins genetics, Protozoan Proteins metabolism, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, Sequence Alignment, Sequence Homology, Amino Acid, Species Specificity, Substrate Specificity, Toxoplasma chemistry, gamma-Aminobutyric Acid metabolism, Ornithine analogs & derivatives, Ornithine chemistry, Ornithine-Oxo-Acid Transaminase chemistry, Protozoan Proteins chemistry, Toxoplasma enzymology, gamma-Aminobutyric Acid chemistry
- Abstract
Toxoplasma gondii is a protozoan parasite of medical and veterinary relevance responsible for toxoplasmosis in humans. As an efficacious vaccine remains a challenge, chemotherapy is still the most effective way to combat the disease. In search of novel druggable targets, we performed a thorough characterization of the putative pyridoxal 5'-phosphate (PLP)-dependent enzyme ornithine aminotransferase from T. gondii ME49 (TgOAT). We overexpressed the protein in Escherichia coli and analysed its molecular and kinetic properties by UV-visible absorbance, fluorescence and CD spectroscopy, in addition to kinetic studies of both the steady state and pre-steady state. TgOAT is largely similar to OATs from other species regarding its general transamination mechanism and spectral properties of PLP; however, it does not show a specific ornithine aminotransferase activity like its human homologue, but exhibits both N-acetylornithine and γ-aminobutyric acid (GABA) transaminase activity in vitro , suggesting a role in both arginine and GABA metabolism in vivo The presence of Val79 in the active site of TgOAT in place of Tyr, as in its human counterpart, provides the necessary room to accommodate N-acetylornithine and GABA, resembling the active site arrangement of GABA transaminases. Moreover, mutation of Val79 to Tyr results in a change of substrate preference between GABA, N-acetylornithine and L-ornithine, suggesting a key role of Val79 in defining substrate specificity. The findings that TgOAT possesses parasite-specific structural features as well as differing substrate specificity from its human homologue make it an attractive target for anti-toxoplasmosis inhibitor design that can be exploited for chemotherapeutic intervention., (© 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.)
- Published
- 2017
- Full Text
- View/download PDF
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