Le teorie delle aree valutarie ottimali: profili storici e interpretativi

Fin dai suoi albori il processo d’integrazione europea, nel periodo post-bellico, si caratterizza per un carattere di forte unicità ed innovazione. La possibilità – o l’onere – oggi più che mai, di un’organizzazione sovra-statale capace di unire esigenze economiche, fiscali, politiche, ma soprattutto ideologiche profondamente differenti, rappresentava un forte azzardo e, contemporaneamente, un coraggioso tentativo di garantire pace e stabilità economica. La creazione di una comunità unica, con tutti i suoi risvolti geo-politici, ma anche economici, si è sostanzialmente configurata per molti anni come un vero e proprio successo. Per quanto riguarda un’analisi esclusivamente economica, emblematico risulta essere non tanto l’abbattimento delle barriere commerciali, doganali e degli ostacoli al libero scambio di merci e persone (fenomeno questo che proprio in questi mesi sta dividendo l’opinione pubblica europea), quanto soprattutto, l’adozione di una moneta unica. Scopo del presente lavoro è quello di analizzare i principali costi e benefici nell’adozione di una valuta comune, partendo proprio dall’interrogativo che lo stesso padre fondatore della teoria delle aree valutarie ottimali, Robert Mundell – già nei primi anni Sessanta del XX° secolo – si poneva. Egli si domandò quali condizioni dovessero essere soddisfatte affinché per un paese non fosse eccessivamente costoso rinunciare all’indipendenza monetaria, e quali possano essere i mezzi con i quali stimolare variabili fondamentali come produzione e domanda aggregata. Al fine di definire l’area geografica coincidente con quella valutaria ottimale è, dunque, necessario verificare la presenza di una serie di connotati economici ben precisi. L’obiettivo che mi sono posto è quello di individuare in primo luogo, i pensieri fondamentali dei principali autori in materia di aree valutarie e, sulla base di tali teorie, rispondere alla domanda se l’Eurozona è un’area valutaria “ottimale, oppure ci possono essere delle misure correttive che la possono rendere tale. In secondo luogo, come tali teorie vennero confutate e criticate dalla letteratura economica degli anni Ottanta e Novanta che prese il passo alla corrente tradizionale: la teoria della credibilità. Tale filone di pensiero sembrava rappresentare la ‘nuova’ teoria delle aree valutarie ottimali, ma rinunciare alla discrezionalità monetaria per stabilire delle regole fisse, come l’adesione ad un’Unione monetaria, è una strada che condurrà, sempre e comunque, a dei benefici superiori ai costi? È sempre così anche di fronte ad uno shock asimmetrico dell’economia? Sono questi gli interrogativi da cui siamo partiti per sviluppare questo ‘nuovo’ filone teorico. C’è da precisare come, nella letteratura economica, sia presente ambiguità e confusione nel definire i concetti di “unione monetaria” ed “unione valutaria”. Un paese che fissa il tasso di cambio della propria valuta e permette la libera circolazione dei capitali rinuncia al controllo sulla politica monetaria nazionale. Questo sacrificio è un esempio dell’impossibilità per un paese di conseguire più di due tra i seguenti obiettivi: a) Stabilità del tasso di cambio; b) Politica monetaria orientata agli obiettivi interni; c) Libertà dei movimenti internazionali di capitali. La necessità di scegliere solo due caratteristiche su tre è un trilemma per i policy maker. È un “trilemma” anziché un dilemma perché le opzioni disponibili sono 3: a) e b), a) e c) o b) e c). Ciò che uno dei padri fondatori dell’euro, Tommaso Padoa-Schioppa, ha voluto sottolineare, è che un mercato in cui vi sia contemporaneamente la libera circolazione di materie prime (input) e di prodotti finiti (output) non è un mercato ‘sostenibile’. Potrebbe rappresentare un ostacolo all’unione valutaria se le politiche macroeconomiche non fossero sostenute da qualche istituto sovranazionale. Ecco che, le osservazioni da fare diventano due. In primo luogo, il trasferimento della sovranità delle politiche economiche dalle autorità nazionali alle autorità sovranazionali (come il Sistema Europeo di Banche Centrali). In secondo luogo, la libera circolazione di materie prime e di prodotti finiti in contemporanea, potrebbe giocare un ruolo chiave sull’unione valutaria a seconda del contesto istituzionale di riferimento. Guardando all’evoluzione dell’Eurozona, negli ultimi anni sembra che le osservazioni di Padoa-Schioppa non siano state totalmente rispettate. Affrontare la tematica delle aree valutarie ottimali in un’ottica storica, significa soffermarsi su uno dei temi più dibattuti in Europa, e proprio per tale importanza, il margine di errore deve essere bassissimo. D’altro lato, c’è da sottolineare che il processo di armonizzazione europeo non ha trovato certo una strada ‘percorribile’. La presenza di forti dislivelli tra Paesi all’interno dell’Unione Europea in termini di effetti della crisi economica, tanto sulla sfera finanziaria quanto su quella più reale, rappresentano una delle maggiori fonti d’incertezza riguardanti il destino dell’unione monetaria europea. È proprio in questo contesto che il presente lavoro vuole essere inserito. Dopo un’attenta analisi dei costi, dei benefici e un oculato confronto tra essi, il focus è rivolto sulle unioni monetarie “incomplete”. Considereremo due tipologie di scenari in cui è presente il problema dell’incompletezza, e ci porremo l’interrogativo – a cui risponderemo puntualmente – su come renderle complete. Termineremo il lavoro approfondendo i principali risultati che, grazie alla teoria delle aree valutarie ottimali, sono visibili con l’adozione di una valuta comune. E, oltre ai risultati ottenuti, delineeremo i principali scenari in ottica prospettica

Total Parathyroidectomy with Subcutaneous Parathyroid Forearm Autotransplantation in the Treatment of Secondary Hyperparathyroidism: A Single-Center Experience.

Abstract Introduction Secondary hyperparathyroidism is common in chronic kidney disease. Parathyroidectomy is indicated in refractory hyperparathyroidism when medical treatments and so the parathyroid hormone levels cannot be lowered to acceptable values without causing significant hyperphosphatemia or hypercalcemia. The aim of this study is to compare the efficacy and safety of total parathyroidectomy with subcutaneous forearm autotransplantation with total parathyroidectomy with intramuscular forearm autotransplantation. Materials and Methods A single-center retrospective cohort study of total parathyroidectomy with forearm autotransplantation from January 2002 to February 2013 was performed. According to the surgical technique, patients were divided into an intramuscular group (Group 1) and a subcutaneous group (Group 2). 38 patients with secondary hyperparathyroidism were enrolled; 23 patients were subjected to total parathyroidectomy with parathyroid tissue replanting in the subcutaneous forearm of the upper nondominant limb, while 15 patients were subjected to replanting in the intramuscular seat. Results A total of 38 patients (56 ± 13 years) were enrolled. In both groups, the preoperative iPTH value was markedly high, 1750 ± 619 pg/ml in the intramuscular autotransplantation group and 1527 ± 451 pg/ml in the subcutaneous autotransplantation group (p = 0.079). Transient hypoparathyroidism was shown in 7 patients, and 1 patient showed persistent hypoparathyroidism (p = 0.387). 2 patients showed persistent hyperparathyroidism (p = 0.816), and in 2 others was found recurrent hyperparathyroidism (p = 0.816); 3 of them underwent autograftectomy. The anterior compartment of the forearm nondominant limb was sacrificed in 1 case of intramuscular autotransplantation with functional arm deficit. Conclusions The efficacy and safety of parathyroid tissue autotransplantation in the subcutaneous forearm of the upper nondominant limb is confirmed with a good rate of tissue engraftment and with a comparable number of postsurgical transient and persistent hypoparathyroidism and hyperparathyroidism incidence in both techniques. Furthermore, this technique preserves arm functionality in the case of autograftectomy. Consequently, it is our opinion that total parathyroidectomy with subcutaneous forearm autotransplantation is currently the best choice

Role of Cinchona Alkaloids in the Enantio- and Diastereoselective Synthesis of Axially Chiral Compounds

Asymmetric synthesis using organic catalysts has evolved since it was first realized and defined. Nowadays, it can be considered a valid alternative to transition metal catalysis for synthesizing chiral molecules. According to the literature, the number of asymmetric organocatalytic processes associated with atropisomer synthesis has rapidly increased over the past 10 years because organocatalysis addresses the challenges posed by the most widespread strategies used for preparing axially chiral molecules with satisfactory results. These strategies, useful to prepare a wide range of C–C, C–heteroatom, and N–N atropisomers, vary from kinetic resolution to direct arylation, desymmetrization, and central-to-axial chirality conversion. In this field, our contribution focuses on determining novel methods for synthesizing atropisomers, during which, in most cases, the construction of one or more stereogenic centers other than the stereogenic axis occurred. To efficiently address this challenge, we exploited the ability of catalysts based on a cinchona alkaloid scaffold to realize enantioselective organic transformations. Desymmetrization of N-(2-tert-butylphenyl) maleimides was one of the first strategies that we pursued for preparing C–N atropisomers. The main principle is based on the presence of a rotationally hindered C–N single bond owing to the presence of a large tert-butyl group. Following the peculiar reactivity of this type of substrate as a powerful electrophile and dienophile, we realized several transformations. First, we investigated the vinylogous Michael addition of 3-substituted cyclohexenones, where a stereogenic axis and two contiguous stereocenters were concomitantly and remotely formed and stereocontrolled using a primary amine catalyst. Subsequently, we realized desymmetrization via an organocatalytic Diels–Alder reaction of activated unsaturated ketones that enabled highly atropselective transformation with efficient diastereoselectivity, thereby simultaneously controlling four stereogenic elements. Employing chiral organic bases allowed us to realize efficient desymmetrizations using carbon nucleophiles, such as 1,3-dicarbonyl compounds, cyanoacetates, and oxindoles. These reactions, performed with different types of catalysts, highlighted the versatility of organocatalysis as a powerful strategy for atropselective desymmetrization of pro-axially chiral maleimides. Hereafter, we studied the Friedel–Crafts alkylation of naphthols with indenones, a powerful method for enantioselective synthesis of conformationally restricted diastereoisomeric indanones. We realized the first axially chiral selective Knoevenagel condensation using cinchona alkaloid primary amine as the catalyst. This reaction provided a powerful method to access enantioenriched olefins containing the oxindole core. Subsequently, we initiated an intense program for the computational investigation of the reaction mechanism of our atropselective processes. An understanding of the catalytic activity for vinylogous atropselective desymmetrization as well as of the role played by the acidic cocatalyst used for the experimental work was achieved. Recently, we have garnered interest in the novel frontiers of atropselective synthesis. As observed in recent publications, there is considerable interest in the development of methods for preparing N–N atropisomers, an emerging topic in the field of atropselective synthesis. We focused on the synthesis of hydrazide atropisomers by developing a one-pot sequential catalysis protocol based on two sequential organocatalytic reactions that provided high stereocontrol of two contiguous stereogenic elements

Multiple primary malignancies of the liver and the colon: a complex diagnostic and decisional process with a final unanswered question

We herein present the case of a 78-year-old man with an incidental finding of a solid hepatic mass without symptoms and only a laparotomic cholecystectomy for acute cholecystitis in the past surgical history. A colonoscopy, a magnetic resonance imaging scan, a positron emission tomography scan, and a computed tomography scan completed the preoperative workup: a neoplastic lesion 4.3 × 3 cm in size was diagnosed at segments IV and V, associated with a neoplastic involvement of the splenic flexure without signs of colonic occlusion. After colonic resection, a frozen section on a granulomatous-like tissue at gastric border suggested a diagnosis of an adenocarcinoma of bilio-pancreatic type, changing the surgical strategy to include gastric resection and hepatic pedicle node dissection. The discussion turns around the idea that a final diagnosis of colon cancer with regional nodal involvement (pT3N1) and metastatic gallbladder cancer with multiple peritoneal seedings cannot be excluded

Platinum(II)-Acyclovir Complexes: Synthesis, Antiviral and Antitumour Activity

A platinum(II) complex with the antiviral drug acyclovir was synthesized and its antiviral and anticancer properties were investigated in comparison to those of acyclovir and cisplatin. The platinum-acyclovir complex maintained the antiviral activity of the parent drug acyclovir, though showing a minor efficacy on a molar basis (ID50  =   7.85 and 1.02 μΜ for platinum-acyclovir and cisplatin, respectively). As anticancer agent, the platinum-acyclovir complex was markedly less potent than cisplatin on a mole-equivalent basis, but it was as effective as cisplatin when equitoxic dosages were administered in vivo to P388 leukaemia-bearing mice (%T/C = 209 and 211 for platinum-acyclovir and cisplatin, respectively). The platinum-acyclovir complex was also active against a cisplatin-resistant subline of the P388 leukaemia (%T/C = 140), thus suggesting a different mechanism of action. The DNA interaction properties (sequence specificity and interstrand cross-linking ability) of platinum-acyclovir were also investigated in comparison to those of cisplatin and [Pt(dien)Cl]+, an antitumour-inactive platinum-triamine compound. The results of this study point to a potential new drug endowed, at the same time, with antiviral and anticancer activity and characterized by DNA interaction properties different from those of cisplatin

Dysplasia in perforated intestinal pneumatosis complicating a previous jejuno-ileal bypass: a cautionary note.

We present the case of an elderly woman who devel- oped a bowel perforation related to pneumatosis intes- tinalis, 33 years after a jejuno-ileal bypass for severe obesity. Final histological examination revealed the presence of dysplasia in the resected specimen. On the basis of our case and a review of the literature, we discuss the etiopathogenesis, the clinical aspects and the treatment of this rare condition

Clinical and biological significance of miR-23b and miR-193a in human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common cancer of the liver with a very poor prognosis. The dysregulation of microRNAs (miRs) is indeed implicated in HCC onset and progression. In this study, we have evaluated the expression of miR-23b and miR-193a in a large cohort of 59 and 67 HCC patients, respectively. miR-23b and miR-193a resulted significantly down-regulated in primary HCCs compared to their matched peritumoral counterparts. Furthermore, patients with higher miR-193a expression exhibited longer OS and DFS, suggesting that miR-193a may be a molecular prognostic factor for HCC patients. Since the regulation of miRs by DNA methylation may occur in human cancers, we verified whether the down-modulation of miR-23b and miR-193a in HCC tissues could be related to DNA methylation. An inverse trend between miR-23b expression and DNA methylation was observed, indicating that miR-23b can be epigenetically regulated. By contrast, the down-regulation of miR-193a was not mediated by DNA methylation. To verify the potential role of miR-23b and miR-193a as responsive molecular targets in vitro, we used the inhibitor of DNA methylation 5-aza-dC to restore miR-23b expression level in combination with miR-193a transfection. The combined treatment led to a significant inhibition of cellular proliferation and migration. Taken together, our findings provide evidence that miR-23b and miR-193a may be molecular diagnostic and prognostic factors for HCC; furthermore, miR-23b and miR-193a are responsive molecular targets for limiting HCC cell aggressiveness in combination with the epigenetic drug 5-aza-dC. Moreover, our results provide new advances in the epigenetic regulation of these miRs in HCC