Antonio Arcidiacono

Polyamine involvement in functional activation of human macrophages

Polyamines naturally occur in all living beings and play an important role in the regulation of cell proliferation, differentiation, and functional stimulation of terminally differentiated cells. Our studies, using specific inhibitors of polyamine biosynthesis such as α‐difluoro‐ methylornithine and methylglyoxal‐bis[guanylhydrazone] to prevent polyamine accumulation, have indicated that polyamines are associated with functional activation of human macrophages. Both inhibitors diminished the respiratory burst activity of macrophages induced by lipopolysaccharide and interferon gamma. The methyl‐ glyoxal‐bis[guanylhydrazone] inhibitory effect was concentration‐dependent and could be reversed by spermine, which is the final product of polyamine biosynthesis.

Accumulation of ornithine decarboxylase mRNA accompanies activation of human and mouse monocytes/macrophages

Accumulation of ornithine decarboxylase (ODC) mRNA was investigated in human monocytes and mouse peritoneal macrophages. Treatment of both populations of mononuclear phagocytes with bacterial lipopolysaccharide induced a marked and rapid increase in the accumulation of the ODC gene transcript. A similar phenomenon, albeit less pronounced, was also observed following treatment of human monocytes with human recombinant interferon‐γ. These results suggest a role for ODC, and therefore polyamines, in the regulation of mononuclear phagocyte functions.

Genomics and transcription analysis of human TFIID.

TFIID, a multisubunit protein comprised of TBP (TATA box-binding protein) and TAFIIs (TBP-associated factors), has a central role in transcription initiation at class II promoters. TAFIIs role as mediators of regulatory transcription factors, such as pRb and p53, and their involvement in signal transduction pathways suggest that some may participate in the control of cell proliferation and differentiation: therefore, they could be considered potential protooncogenes or antioncogenes. With the aim of starting to analyse these potential roles, we have determined the genomic position of nine human TAFII genes (TAFII250, TAFII135, TAFII100, TAFII80, TAFII55, TAFII43, TAFII31, TAFII28, TAFII20/15) and of two previously unknown sequences related to TAFII250 and TAFII31, respectively. Except for those encoding TAFII250 and TAFII31, these genes are present in a single copy and, with the exclusion of those for TAFII43 and TAFII28 (both at 6p21), are localized in different segments of the genome. Indeed, six of them map to a chromosomal region commonly altered in specific neoplasias, which defines them as candidates for involvement in oncogenesis. Our experiments also demonstrate that TAFII transcripts are synthesized ubiquitously, mostly at low levels similar to those of TBP. Interestingly, the amount of the major mRNA species detected by TAFII20/15 cDNA is higher, which suggests that the polypeptide it encodes may also perform functions independently of TFIID. TAFII isoforms, indicated by additional bands on Northern blots, may play a role in modulation of TFIID function. These data will be useful for analysing variations of TAFII mRNA phenotype during cell proliferation, differentiation and development, both normal and pathological.

Transcription factor activation and functional stimulation of human monocytes

Activation of expression of genes encoding transcription factors: c-fos and c-jun and formation of AP1 transcriptional complex in human monocytes was investigated. It was found that lipopolysaccharide induced strongly both c-fos and c-jun expression as well as AP1 formation. Interferon gamma activated strongly c-fos and weakly c-jun and AP1. Tumor necrosis factor induced slightly c-fos and had almost no effect on c-jun and AP1. The data suggest that differences in functional responses elicited in monocytes by all three factors may be dependent on different routes on nuclear signalling employed by the factors.

Early results of MitraClip system implantation by real-time three-dimensional speckle-tracking left ventricle analysis.

Aims To appraise the early effect of percutaneous mitral valve repair with the MitraClip system on myocardial function using real-time three-dimensional speckle-tracking echocardiography (3D-STE). Methods Consecutive patients with moderate-to-severe or severe mitral regurgitation, undergoing mitral valve repair with the MitraClip system, were prospectively evaluated during the peri-procedural workout and follow-up. Left ventricular deformation was evaluated by a two-dimensional and 3D speckle-tracking analysis. 3D-STE acquisitions were elaborated obtaining real-time 3D global longitudinal strain evaluation, and by appraising both volumetric and hemodynamic parameters (i.e. left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction, cardiac output, and stroke volume). Results In all, 30 patients were included. At 1-month follow-up, 3D-STE analysis revealed no changes in left ventricular end-diastolic volume (162.6 ± 73.7 ml at baseline vs. 159.8 ± 64.5 ml at 1-month follow-up; P = 0.63) and a downward trend in left ventricular end-systolic volume (104.7 ± 52.0 vs. 100.1 ± 50.4 ml, respectively; P = 0.06). Left ventricular ejection fraction did not significantly increase (38.1 ± 11.3% at baseline vs. 39.4 ± 11.0% at 1-month follow-up; P = 0.20). No significant changes were reported in cardiac output (4.3 ± 2.0 l/min at baseline vs. 4.0 ± 1.5 l/min at follow-up; P = 0.377) and in stroke volume (59.5 ± 25.5 ml at baseline vs. 59.9 ± 20.7 ml at follow-up; P = 0.867). On the contrary, left ventricular deformation capability significantly improved, with the real-time 3D global longitudinal strain value changing from −9.8 ± 4.1% at baseline to −11.0 ± 4.4% at follow-up (P = 0.018). Conclusions Accurately assessing myocardial function by the use of 3D-STE, this study reported irrelevant early changes in left ventricular size, but a positive effect on left ventricular deformation capability following mitral valve repair with the MitraClip system. These preliminary results need to be confirmed in larger series and extended to long-term follow-up.

Multimodality imaging of a left main coronary artery-to-pulmonary artery fistula

We report a case of a 17-year-old young man with a coronary fistula incidentally diagnosed. On transthoracic echocardiography, an abnormal flow draining into the pulmonary trunk was evidenced. Coronary computed tomography confirmed the presence of a small coronary fistula connecting the proximal part of the left anterior descending artery to the pulmonary trunk. As the patient was completely asymptomatic, in order to guide the clinical management and exclude any underlying ischemic phenomena, the patient underwent stress myocardial perfusion scintigraphy which was negative for ischemia.

Three-dimensional echocardiographic and surgical findings in mitral mechanical valve dysfunction.

Periodic echocardiographic evaluation of valve function is recommended in all patients with prosthetic valves. Usually trans-thoracic echocardiography (TTE) is satisfactory to assess prosthetic function. Nevertheless when the TTE is suboptimal or in case of strong clinical doubt of prosthetic valve dysfunction, trans-esophageal echocardiography (TEE) remains the gold standard of imaging. Recent advancements in echocardiography, with the three-dimensional (3D) reconstruction, provide an incremental diagnostic value as compared to two-dimensional TEE. In addition, 3D-TEE gives unique views that add extra morphological and anatomical information, providing a very accurate presurgical evaluation.

Sténoses laryngées: Traitement endoscopique au laser CO2

RésuméLes sténoses du larynx posent des problèmes complexes. Aucune technique ne s’est révélée totalement satisfaisante dans le traitement des différentes variétés de sténoses. Ľemploi du laser CO2 dans le traitement endoscopique des sténoses du larynx a conduit dans le Département O.R.L. de ľUniversité de Catania, à traiter avec succès des sténoses congénitales et acquises.Trois échecs ont été enregistrés au niveau de sténoses sévères de longue date, ďétiologie inflammatoire et associées a un important remaniement cartilagineux, justifiant le recours à une intervention chirurgicale par voie externe.Comparée aux méthodes traditionnelles, la technique endoscopique présente plusieurs avantages : éxérèse non hémorragique, nette diminution des processus inflammatoires secondaires, réépithélialisation précoce et morbidité faible, tous consécutifs à la technique même de la chirurgie endoscopique sous laser CO2.SummaryStenosis of the larynx presents perplexing problems. No technique has proved totally satisfactory in the management of all varieties of stenosis. The use of CO2 laser in the endoscopic management of stenoses of the larynx has allowed in the E.N.T. Department of Catania University, to treat successfully congenital or acquired stenoses.Three failures have been recorded from severe longdated stenoses with inflammatory etiology and large cartilaginous involvement for which an external surgical procedure is required.Compared with the traditional systems the advantage are due to the bloodless exeresis, to the great reduction of secondary inflammatory processes, to the early reepithelisation, to the low morbility which are the elements connected with endoscopic surgery with CO2 laser.

Traitement endoscopique au laser CO2 du cancer des cordes vocales

Résumé23 patients atteints de carcinome des cordes vocales, sans atteinte de leur mobilité (T1N0) ont été traites par cordectomie endoscopique au laser CO2 dans le Département O.R.L. de ľUniversite de Catania.En comparaison avec les méthodes chirurgicales traditionnelles, les cordectomies endoscopiques au laser CO2 presentent des avantages ďun point de vue technique : large acces visuel a la lesion et remarquable précision grâce à la micro-chirurgie ; du point de vue biologique : réduction des risques de diffusion néoplasique possible ; du point de vue clinique : traumatisme minime, absence de complications infectieuses, absence ďcedeme et de processus inflammatoires secondaires.Afin ďatteindre ces bons résultats du traitement, il faut avoir la possibilité ďune exposition adéquate du larynx et il importe de respecter correctement les indications chirurgicales.Summary23 patients with vocal cord carcinoma, presenting no changes in the cord motility (T1N0) have been treated in E.N.T. Department of Catania University with an endoscopic surgical cordectomy with CO2 laser.Compared with the traditional surgical systems, endoscopic cordectomies with CO2 laser have advantages in the technical field : the wide vision of the lesion and the remarkable precision by using a surgical microscope ; in the biological field : reduction of risks coming from a possible neoplastic spreading ; in the clinical field : little traumatism, absence of œdema and secondary inflammatory processes.To get good results from this surgical treatment it is necessary to have the possibility of an adequate exposure of larynx and to respect surgical indications.