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1.
J Microsc ; 294(2): 84-89, 2024 May.
Article in English | MEDLINE | ID: mdl-37905779

ABSTRACT

Within this article the importance of the optical light microscopy for the investigation of cement clinker is illustrated by three examples: (a) Ono's method plays an important role in the case of the production of oil well clinker where the reactivity of alite and additionally the melting phase influences strongly the properties of the later cement; (b) the use of secondary fuels can lead to unexpected phenomena in the clinker matrix accompanied by strange changes in colour; (c) for the interpretation of CSA clinkers, the combination of light and scanning electron microscopy can give important information about the formation of clinker phases depending on the burning conditions which can hardly be detected by other methods. However, in case of CSA clinker, there is still little knowledge about the relationship between production and hydraulic properties of the clinker and therefore no systematic documentation is available.

2.
Trials ; 21(1): 192, 2020 Feb 17.
Article in English | MEDLINE | ID: mdl-32066489

ABSTRACT

BACKGROUND: Ticagrelor is a reversibly binding, direct-acting, oral, P2Y12 antagonist used for the prevention of atherothrombotic events in patients with coronary artery disease (CAD). Ticagrelor blocks adenosine reuptake through the inhibition of equilibrative nucleoside transporter 1 (ENT-1) on erythrocytes and platelets, thereby facilitating adenosine-induced physiological responses such as an increase in coronary blood flow velocity. Meanwhile, adenosine plays an important role in triggering ischemic preconditioning through the activation of the A1 receptor. Therefore, an increase in ticagrelor-enhanced adenosine bioavailability may confer beneficial effects through mechanisms related to preconditioning activation and improvement of coronary microvascular dysfunction. METHODS: To determine whether ticagrelor can trigger ischemic preconditioning and influence microvascular function, we designed this prospective, open-label, pilot study that enrolled patients with stable multivessel CAD requiring staged, fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI). Participants will be randomized in 1:1 ratios either to ticagrelor (loading dose (LD) 180 mg, maintenance dose (MD) 90 mg bid) or to clopidogrel (LD 600 mg, MD 75 mg) from 3 to 1 days before the scheduled PCI. The PCI operators will be blinded to the randomization arm. The primary endpoint is the delta (difference) between ST segment elevations (in millimeters, mm) as assessed by intracoronary electrocardiogram (ECG) during the two-step sequential coronary balloon inflation in the culprit vessel. Secondary endpoints are 1) changes in coronary flow reserve (CFR), index of microvascular resistance (IMR), and FFR measured in the culprit vessel and reference vessel at the end of PCI, and 2) angina score during inflations. This study started in 2018 with the aim of enrolling 100 patients. Based on the rate of negative FFR up to 30% and a drop-out rate up to 10%, we expect to detect an absolute difference of 4 mm among the study arms in the mean change of ST elevation following repeated balloon inflations. All study procedures were reviewed and approved by the Ethical Committee of the Catholic University of Sacred Heart. DISCUSSION: Ticagrelor might improve ischemia tolerance and microvascular function compared to clopidogrel, and these effects might translate to better long-term clinical outcomes. TRIAL REGISTRATION: EudraCT No. 2016-004746-28. No. NCT02701140.  TRIAL STATUS: Information provided in this manuscript refers to the definitive version (n. 3.0) of the study protocol, dated 31 October 2017, and includes all protocol amendments. Recruitment started on 18 September 2018 and is currently ongoing. The enrollment is expected to be completed by the end of 2019. TRIAL SPONSOR: Fondazione Policlinico Universitario A. Gemelli - Roma, Polo di Scienze Cardiovascolari e Toraciche, Largo Agostino Gemelli 8, 00168 Rome, Italy.


Subject(s)
Coronary Artery Disease/surgery , Ischemic Preconditioning, Myocardial/methods , Myocardial Reperfusion Injury/prevention & control , Percutaneous Coronary Intervention/adverse effects , Ticagrelor/administration & dosage , Adolescent , Adult , Aged , Clinical Trials, Phase II as Topic , Clinical Trials, Phase III as Topic , Clopidogrel/administration & dosage , Coronary Vessels/drug effects , Female , Fractional Flow Reserve, Myocardial/drug effects , Humans , Male , Microvessels/drug effects , Middle Aged , Myocardial Reperfusion Injury/etiology , Pilot Projects , Preoperative Care/methods , Purinergic P2Y Receptor Antagonists/administration & dosage , Randomized Controlled Trials as Topic , Treatment Outcome , Vascular Resistance/drug effects , Young Adult
3.
Childs Nerv Syst ; 36(9): 2093-2097, 2020 09.
Article in English | MEDLINE | ID: mdl-31965290

ABSTRACT

INTRODUCTION: Mucopolysaccharidosis (MPS) IIIB is a lysosomal disorder in which a deficiency in α-N-acetylglucosaminidase impairs the degradation of heparan sulphate, which accumulates in tissues causing multiple organs dysfunction. This disease is associated with significant central nervous system (CNS) abnormalities, but a presentation with a tumour-like lesion has never been reported so far. CLINICAL PRESENTATION: The present report describes the case of a 5-year-old girl suffering from MPS IIIB who developed a cerebellar lesion with evident mass effect. She underwent surgery with a subsequent notable improvement of her clinical picture. Surprisingly, the pathological analysis revealed the lesion to have the typical MPS features. CONCLUSION: This case would describe a neglected possible presentation of MPS IIIB with a lesion mimicking a neoplasm, which could even be successfully treated with surgery.


Subject(s)
Cerebellar Neoplasms , Mucopolysaccharidoses , Mucopolysaccharidosis III , Cerebellar Neoplasms/diagnostic imaging , Cerebellar Neoplasms/surgery , Child, Preschool , Female , Glycosaminoglycans , Humans , Lysosomes , Mucopolysaccharidosis III/diagnostic imaging
4.
Neuropediatrics ; 45(2): 123-8, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24258525

ABSTRACT

Argininemia is a rare inherited disorder of the urea cycle because of a deficiency of the enzyme arginase I causing an increase of arginine and guanidino compounds in the blood, urine, and cerebrospinal fluid. The clinical picture is characterized by a mild cognitive dysfunction, progressive asymmetrical paraparesis, and seizures. Here, we describe two cases of argininemia where either epilepsia partialis continua (EPC) or nonconvulsive status epilepticus (NCSE) were the presenting manifestations of epilepsy. This is the first report of EPC in an urea cycle disorder. In both the cases, status epilepticus resolved with anticonvulsive drugs. EPC was successfully treated with levetiracetam, and NCSE with valproic acid. No side effects were observed. Because hyperammonemia and NCSE may have the same features of stupor, a neurophysiological approach might prove useful in differentiating these two conditions. Overall, our results strongly indicate that a correct NCSE diagnosis is mandatory to prevent further deterioration in these patients.


Subject(s)
Epilepsia Partialis Continua/diagnosis , Epilepsy, Generalized/diagnosis , Hyperargininemia/diagnosis , Child , Child, Preschool , Epilepsia Partialis Continua/complications , Epilepsy, Generalized/complications , Humans , Hyperargininemia/complications , Male
5.
J Ultrasound ; 14(1): 14-7, 2011 Mar.
Article in English | MEDLINE | ID: mdl-23396826

ABSTRACT

Lipoblastomas are rare, benign tumors of mesenchymal origin that contain adipose tissue. They usually develop in the soft tissues of an extremity in infants, children, and young adolescents. We report the case of a 22-month old girl referred to our staff for swelling in the supraclavicular fossa, which was observed when the child cried. The ulstrasonographic examination revealed a mass in the anterosuperior portion of the mediastinum that extended into the right supraclacular fossa. The lesion was weakly hyperechoic with clear-cut margins and did not appear to invade surrounding tissues. On CT, it appeared inhomogeneously hypodense with denitometric characteristics of adipose tissue. On MRI, it was hyperintense on both T1- and T2-weighted sequences and reduced signal intensity in FAT SAT sequences. In light of the imaging features and predominant adipose tissue component, the mass was diagnosed as a mediastinal lipoblastoma, and this diagnosis was confirmed by surgical histology.


SommarioIl lipoblastoma è una rara neoplasia mesenchimale, benigna, contenente tessuto adiposo, che colpisce l'infanzia e la prima adolescenza e che si localizza preferenzialmente nelle parti molli delle estremità. Nel nostro caso una bambina di 22 mesi è giunta alla nostra osservazione per una tumefazione della fossetta sovraclaveare che si rendeva manifesta durante il pianto. L'esame ecografico ha evidenziato una neoformazione del mediastino antero-superiore a parziale sviluppo nella fossetta sovraclaveare destra, che appariva tenuemente iperecogena a margini netti. Tale neoformazione non presentava caratteristiche infiltrative nei confronti delle strutture limitrofe. La massa appariva alla TC disomogeneamente ipodensa, a densitometria adiposa, mentre alla RM risultava iperintensa nelle immagini T1 e T2-pesate, con abbattimento del segnale nelle sequenze FAT SAT. Le caratteristiche d'imaging ed in particolare la prevalenza di tessuto adiposo ci hanno suggerito l'ipotesi diagnostica di un lipoblastoma mediastinico, che è stata confermata dall'esame istologico eseguito sul pezzo operatorio.

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