Mechanochemical Simmons–Smith cyclopropanation via ball-milling-enabled activation of zinc(0)

The bulk solvent-free synthesis of cyclopropanes via a ball-milling-enabled Simmons–Smith reaction is herein described

An Erythematous-squamous Lesion of the Foot: A Quiz

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APPLICAZIONE SPERIMENTALE DI VASI UMANI DECELLULARIZZATI DI PICCOLO CALIBRO

Tissue engineering mean a wide field of science application in searching the substitusion by different process of damaged human tissue. The main intent is to obtain scaffold that can perfectly mimic the structural and functional characteristics of damaged tissues or organs. In the field of vascular graft numerous studies were conducted to obtain suitable tissue that could supplant the use of autologous bypassor even the littlest vessel employed in microsurgery. Over the years, various solutions have been proposed. The use of resorbable or non-resorbable vascular synthetic conduits, associated or not to stem cells and growth factors, small-caliber decellularized vessels and scaffold-free methods have been described in the literature. First, our study has produced experimental animal models in which a section of the rabbit femoral vessels was replaced by small caliber (inner diameter < 6 mm) human decellularized vessel. Materials and methods Two arteries and two human veins of small caliber (< 6 mm) obtained by upper arm lesions not suitable for surgical procedure were withdrawn and subjected to a process of decellularization according to a modified Sheridan’s protocol. The effectiveness of the process was shown in vitro with histological, immunohistochemical, ultrastructural, and qualitative and quantitative analysis of DNA. Mechanical testing and functional ecodoppler in vivo were also performed. Decellularized vessels were implanted in vivo in rabbit femoral vessels. The patency was verified, in vivo, at time 0, 10 and 20 minutes later. After 30 days for vein implants and 10 and 40 days for artery implants, the rabbits were sacrificed. The patency of grafts, the inflammatory process and re-endothelialization was tested with histological and immunophenotypical analysis. At the same time we analyzed also synthetic vessel as control , after two weeks of implantation. Results The various assays of decellularized vessels, in vitro, demonstrated the success of the process. The cellular component was eliminated without altering the composition and three-dimensional structure of extra cellular matrix. It was also confirmed by mechanical testing. The scaffolds were implanted successfully in all models and the patency was maintained until animals’ sacrifice, as also documented by ecocolordoppler evaluation. The histological and immunophenotypical analysis of taken scaffolds showed a minimal inflammatory process, the maintenance of the extracellular matrix structure and the wall and luminal surface re-cellularization. The syntethic vessel demonstrate complete thrombosis. Conclusions The adjustments made to the decellularization protocol proposed by Sheridan helped to keep acceptable length of the process maintaining the same effectiveness. Non-use of endothelial stem cells reduced costs even if, for longer grafts the use of cells to improve biocompatibility seems to be necessary. The histological studies on withdrawn grafts have demonstrated a minimal presence of inflammatory processes, a complete patent in two weeks till eight weeks and the presence of a process of re-cellularization. The excellent biocompatibility of implanted scaffolds suggest the possibility of a subsequent application in clinical microvascular field and, in the future, for the establishment of a tissue bank to find substitutes with suitable caliber and length. Additional animal testing, with long time survival, mechanical and histological analysis are definitely essential to determine the effectiveness of these implants and think of a possible clinical trials

L’‘incapacità’ di riconoscere la responsabilità: Riflessioni a partire da Ritorno in Germania di Hannah Arendt

After her visit to Germany in 1949/50 Hannah Arendt wrote the essay The Aftermath of Nazi-Rule. Report of Germany (1950) in which she collects her reflections on post-war German society. Starting from this analysis, the present article aims to investigate the causes of the inexplicable indifference to Nazi crimes that Arendt observes in the German people. While Arendt emphasizes the inability to think (and feel) provoked by the regime, A. and M. Mitscherlich focus on the failure to process the traumatic ‘loss of the Führer’. In both cases, a mechanism of reality distortion gets triggered, resulting in the repression of the past and the denial of one’s own guilt and responsibility. The studies by Bar-On, Pohl and Welzer (et al.) show how these repression processes are also active in later generations, even today, representing a threat to a successful reworking of the past, to the preservation of collective memory and to the recognition of one’s own responsibility not only for the past, but also for the present and future

Feast of sacrifice and orf, Milan, Italy, 2015&#8211;2018

Orf (ecthyma contagiosum) is an infection of the skin caused by a DNA virus belonging to the genus Parapoxvirus. We recently observed 7 cases of orf in Muslim men living in the metropolitan area of Milan, Italy, who acquired the infection after the Feast of Sacrific

Treatment of a Severe Pediatric Lyell Syndrome with Amniotic Membrane: Case Report and Histological Findings

Background: Lyell Syndrome (TEN, Toxic epidermal necrolysis) represents a medical emergency particularly in pediatric patients in whom the massive skin damage can quickly lead to multi-organ dysfunction and death. Prompt restoration of the physiologic mucosal/cutaneous barrier is mandatory. The use of amniotic membranes has been described in the treatment of ophthalmic Lyell Syndrome, but its use has not yet been adopted for the management of larger cutaneous wounds. Study Hypothesis: Here we report the use of amniotic membranes in a pediatric case of severe Lyell Syndrome with complete skin surface, ocular and mucosal involvement with life threating presentation. Methods: A 7-year old female was admitted to our Burn Centre for severe cutaneous/mucosal exfoliation (100% Total body surface area, TBSA) as a result of an adverse reaction to ibuprofen administration. Supportive fluid administration, cardiac-pulmonary assistance and pain management were complemented by serial grafting of amniotic membranes on all affected areas to provide coverage of the exfoliated skin/mucosa. Biopsies were obtained to monitor histological skin changes. Results: The patient showed an excellent response to amniotic membrane treatment, with rapid restoration of mucosal and cutaneous layers in the grafted areas. This resulted in a decreased need for dressing changes, avoidance of additional surgeries and a reduced dependence on supportive therapy. Lower pain levels than usually expected led to a reduced need for narcotic pain medications and allowed for early physical rehabilitation and a short hospital stay. Histology confirmed evidence of topical immune-modulation in treated areas (reduction of inflammatory infiltrate). Conclusion: As we tested in numerously TEN and burn pediatric injuries Amniotic membranes with their regenerative and immune-modulatory effects may represent an life saving treatment even in the worst cases of pediatric Lyell syndrome