Organocatalysts and metal-based catalysts: a journey toward the development of new catalytic materials

Organocatalysis and metal-based catalysis represent two of the main pillars of catalytic reactions and have witnessed a huge interest in the last decade. Immobilization, recovery and reuse of these catalysts is of primary importance because of the large amount used especially in the case of organocatalysts. On the other hand, metal-based catalysts must be recovered even if used in low amount, in order to avoid contamination of the product. In this context, we started several years ago investigations on the use of supported ionic liquid phases for the asymmetric organocatalysis mediated by proline.1 This approach is an example of a “release and catch” catalytic system.2 Starting from this example, we describe the development of new catalytic materials based on the use of i) supported ionic liquid phase (Scheme 1a) ii) covalently linked catalysts (scheme 1b) iii) ionic liquid-modified fullerenes (Scheme 1c), with the goal to obtain recyclable catalytic materials for C-C coupling reactions and alcohols oxidation.3 These studies have paved the way for the development of new hybrid materials such as silica-fullerenes or CNT-IL or POSS-IL

Impact of Future Remnant Liver Volume on Post-Hepatectomy Regeneration in Non-Cirrhotic Livers

Objective: The purpose of the study is to detect if some parameters can be considered as predictors of liver regeneration in two different patient populations composed of in living donors for adult to adult living donor liver transplant and patients with hepatic malignancies within a single institution.Summary Background Data: Preoperative multi-detector computed tomography volumetry is an essential tool to assess the volume of the remnant liver. Methods: a retrospective analysis from an ongoing clinical study on 100 liver resections, between 2004 and 2010. 70 patients were right lobe living donors for liver transplantation and 30 patients were resected for treatment of tumors. Pre-surgical factors such as age, weight, height, body mass index (BMI), original liver volume, future remnant liver volume (FRLV), spleen volume, liver function tests, creatinine, platelet count, steatosis, portal vein embolization (PVE) and number of resected segments were analyzed to evidence potential markers for liver regeneration. Results: Follow-up period did not influence the amount of liver regenerated: the linear regression evidenced that there is no correlation between percentage of liver regeneration and time of follow-up (p=0.88). The pre-surgical variables that resulted markers of liver regeneration include higher preoperative values of BMI (p=0.01), bilirubin(p=0.04), glucose (p=0.05) and GGT (p=0.014); the most important association was revealed regarding the lower FRLV (pConclusions: Liver regeneration follows similar pathway in living donor and in patients resected for cancer. Small FRLV tends to regenerate more and faster, confirming that a larger resections may lead to a greater promotion of liver regeneration in patients with optimal conditions in terms of body habitus, preoperative liver function tests and glucose level

Organocatalizzatori e liquidi ionici supportati: nuovi materiali in sintesi organica

Nell’ultimo decennio l’organocatalisi e i liquidi ionici hanno rappresentato due campi di grande interesse scientifico. Gli organocatalizzatori hanno trovato particolare impiego in sintesi enantioselettive conducendo a prodotti finali con alte rese e selettività. I liquidi ionici sono stati estensivamente utilizzati come solventi alternativi e, opportunamente modificati, come catalizzatori o loro supporti. Uno sviluppo attuale che accomuna questi due campi di ricerca consiste nella possibilità di immobilizzazione di organocatalizzatori e liquidi ionici per trasformarli in materiali riciclabili con ampie capacità di utilizzo in chimica organica. Negli ultimi anni, il nostro gruppo di ricerca si è occupato di organocatalizzatori e liquidi ionici supportati. E’ stata sviluppata una metodologia sintetica per l’ancoraggio di organocatalizzatori su resine polistireniche attraverso una reazione tiolo-ene, permettendo di ottenere un largo numero di materiali catalitici che sono stati impiegati in reazioni aldoliche, di -selenenilazione e di Michael (Figura 1).1-2 Nel campo dei liquidi ionici supportati (SILP) ci siamo occupati del loro uso nel campo delle reazioni catalizzate da metalli che in organocatalisi. Inoltre, i SILP sono stati efficacemente impiegati in reazioni di apertura di epossidi in CO2 supercritica per fornire carbonati ciclici.3-4 In questo campo abbiamo sviluppato due tipi di materiali, monostrato e multistrato (Figura 2)

Processing and characterization of dual phase steel foam

Porous materials featuring cellular structures are known to have many interesting combinations of physical and mechanical properties. Some of them have been extensively used in the transportation field (i.e. balsa wood). Steel foams presented promising theoretical properties for both functional and structural applications in transportation, but processing of such a kind of foams is complex due to their high melting point. Recently a technique for processing Cu-based alloys open-cell foams through the molten metal infiltration of a leachable bed of amorphous SiO2 particles was proposed. A variation of the proposed technique that uses SiC particles as space holder is now presented and was recently successfully applied for dual phase steel foam processing. Results from a processing of dual phase DP500 steel foams, including some morphological, micro-structural and mechanical characterization, are here presented

The role of basiliximab in the evolving renal transplantation immunosuppression protocol

Basiliximab is a chimeric mouse-human monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor on activated T lymphocytes. It was shown in phase III trials to reduce the number and severity of acute rejection episodes in the first year following renal transplantation in adults and children, with a reasonable cost-benefit ratio. The drug does not increase the incidence of opportunistic infections or malignancies above baseline in patients treated with conventional calcineurin inhibitor-based immunosuppression. In the field of renal transplantation, basiliximab does not increase kidney or patient survival, despite the reduction in the number of rejection episodes. Basiliximab may reduce the incidence of delayed graft function. In comparison with lymphocyte-depleting antibodies basiliximab appears to have equal efficacy in standard immunological risk patients. Recently, IL-2 receptor monoclonal antibodies have been used with the objective of reducing or eliminating the more toxic elements of the standard immunosuppression protocol. Several trials have incorporated basiliximab in protocols designed to avoid or withdraw rapidly corticosteroids, as well as protocols which substitute target-of-rapamycin (TOR) inhibitors for calcineurin inhibitors