Fibro-adipose substitution has a double detrimental effect on the myocardium in arrhythmogenic cardiomyopathy (ACM), worsening arrhythmogenesis by creating a non-conductive substrate, and causing ventricular dysfunction leading to heart failure. Notably, to-date no etiological therapy is available. This work introduces, for the first time, the stromal cardiac compartment as a key player in ACM ventricular adipose substitution: we demonstrated that cardiac human mesenchymal stromal cells undergo adipogenic differentiation both in ACM explanted hearts and in culture through a PKP2-dependent mechanism. Cardiac mesenchymal stromal cells constitute a suitable cellular platform for future mechanistic studies and a potential target for future therapies.

Surgical excision with a safety margin is the cornerstone\ud of treatment of malignant sternal tumors. After sternal resection,\ud the primary goals of chest wall reconstruction are to\ud prevent flail chest with ventilatory impairment, protect the\ud underlying mediastinal structures, and avoid chest deformity.\ud Various techniques and several materials have been\ud used over the years for this purpose.1 This report describes\ud the use of sternal allograft to reconstruct the chest wall after\ud sternal resection

The use of amniotic membrane (AM) is a widespread clinical practice for eye surgeries and the treatment of an increasing number of ocular surface pathologies. Here we describe the AM collection methods and donor selection criteria adopted by our tissue bank to distribute 5349 amniotic membrane patches over the last 12 years for the treatment of several ocular pathologies. Specific quality control measures are described and the long term results attained using the reported procedure are presented. A case of AM utilized to treat severe ocular ulceration is also described as an example of AM transplantation. Collective data for the total amniotic membrane patches deployed to treat various ocular diseases are discussed and success rates for AM transplantations are reported. An extensive follow-up is illustrated. The results suggest that the procedures and protocols used by the Treviso Tissue Bank Foundation and Veneto Eye Bank Foundation for collection, preservation, distribution and follow-up are of an optimal standard. Accordingly, the authors conclude that the safety and efficiency of the proposed procedure for the therapeutic use of AM to treat various ocular pathologies are reproducible, with additional evidence favoring the use of AM as an alternative to conventional medical treatment for certain ocular conditions.

The aim of this work was to compare the effects on human amniotic membrane of freeze-drying and c-irradiation at doses of 10, 20 and 30 kGy, with freezing. For this purpose, nine cytokines (interleukin 10, platelet-derived growth factor-AA, plateletderived growth factor-BB, basic fibroblast growth factor, epidermal growth factor, transforming growth factor beta 1, and tissue inhibitors of metalloproteinase-1, -2, and -4) were titrated in 5 different preparations for each of 3 amniotic membranes included in the study. In addition, the extracellular matrix structure of each sample was assessed by transmission electron microscopy. While freeze-drying did not seem to affect the biological structure or cytokine content of the different amniotic membrane samples, c-irradiation led to a significant decrease in the tissue inhibitors of metalloproteinase-4, basic fibroblast growth factor and epidermal growth factor, and induced structural damage to the epithelium, basement membrane and lamina densa. The higher the irradiation dose the more severe the damage to the amniotic membrane structure. In conclusion, the Authors recommend processing amniotic membrane under sterile conditions to guarantee safety at every step rather than final sterilization with c-irradiation, thereby avoiding alteration to the biological characteristics of the amniotic membrane.

Cryopreserved allogeneic conduits are the elective biocompatible choice among currently available substitutes for surgical replacement in end-stage valvulopathy. However, degeneration occurs in 15 years in adults or faster in children, due to recipient's immunological reactions to donor's antigens. Here, human aortic valves were decellularized by TRICOL, based on Triton X-100 and sodium cholate, and submitted to standard cryopreservation (TRICOL-human aortic valves (hAVs)). Tissue samples were analyzed to study the effects of the combined procedure on original valve architecture and donor's cell removal. Residual amounts of nucleic acids, pathological microorganisms, and detergents were also investigated. TRICOL-hAVs proved to be efficaciously decellularized with removal of donor's cell components and preservation of valve scaffolding. Trivial traces of detergents, no cytotoxicity, and abrogated bioburden were documented. TRICOL-hAVs may represent off-the-shelf alternatives for both aortic and pulmonary valve replacements in pediatric and grown-up with congenital heart disease patients.

Arrhythmogenic cardiomyopathy (ACM) is hallmarked by ventricular fibro-adipogenic alterations, contributing to cardiac dysfunctions and arrhythmias. Although genetically determined (e.g., PKP2 mutations), ACM phenotypes are highly variable. More data on phenotype modulators, clinical prognosticators, and etiological therapies are awaited. We hypothesized that oxidized low-density lipoprotein (oxLDL)-dependent activation of PPARc, a recognized effector of ACM adipogenesis, contributes to disease pathogenesis. ACM patients showing high plasma concentration of oxLDL display severe clinical phenotypes in terms of fat infiltration, ventricular dysfunction, and major arrhythmic event risk. In ACM patient-derived cardiac cells, we demonstrated that oxLDLs are major cofactors of adipogenesis. Mechanistically, the increased lipid accumulation is mediated by oxLDL cell internalization through CD36, ultimately resulting in PPARc upregulation. By boosting oxLDL in a Pkp2 heterozygous knock-out mice through high-fat diet feeding, we confirmed in vivo the oxidized lipid dependency of cardiac adipogenesis and right ventricle systolic impairment, which are counteracted by atorvastatin treatment. The modulatory role of oxidized lipids on ACM adipogenesis, demonstrated at cellular, mouse, and patient levels, represents a novel risk stratification tool and a target for ACM pharmacological strategies.

Object The use of allografts from cadaveric donors has attracted renewed interest in recent years, and pretreatment with cryopreservation and immunosuppression methods has been investigated to maximize axonal regrowth and minimize allograft rejection. The authors wanted to assess the outcome of treatments of brachial plexus stretch injuries with cryopreserved allografts from cadaveric donors in nonimmunosuppressed patients. Methods Ten patients with brachial plexus lesions were submitted to electromyography (EMG) testing 1 and 3 months after a traumatic event and 1 week before surgery to localize and identify the type of lesion. Intraoperative EMG recordings were performed for intraoperative monitoring to select the best surgical strategy, and postoperative EMG was used to follow up patients and determine surgical outcomes. If nerve action potentials (NAPs) were present intraoperatively, neurolysis was performed, whereas muscular/nerve neurotization was performed if NAPs were absent. Cryopreserved allografts obtained from selected cadaveric donors and provided by the tissue bank of Treviso were used for nerve reconstruction in patients who were not treated with immunosuppressive drugs. Results The surgical strategy was selected according to the type and site of the nerve lesion and on the basis of IOM results: 14 cryopreserved allografts were used for 7 muscular neurotizations and for 7 nerve neurotizations, and 5 neurolysis procedures were performed. All of the patients had regained motor function at the 1- and 2-year follow-ups. Conclusions Some variables may affect functional recovery after allograft surgery, and the outcome of peripheral nerve reconstruction is more favorable when patients are carefully evaluated and selected for the surgery. The authors demonstrated that using cryopreserved allografts from cadaveric donors is a valid surgical strategy to restore function of the damaged nerve without the need for any immunosuppressive treatments. This approach offers new perspectives on procedures for extensive reconstruction of brachial and lumbosacral plexuses.

BackgroundArrhythmogenic cardiomyopathy (ACM) is a genetic autosomal disease characterized by abnormal cell-cell adhesion, cardiomyocyte death, progressive fibro-adipose replacement of the myocardium, arrhythmias and sudden death. Several different cell types contribute to the pathogenesis of ACM, including, as recently described, cardiac stromal cells (CStCs). In the present study, we aim to identify ACM-specific expression profiles of human CStCs derived from endomyocardial biopsies of ACM patients and healthy individuals employing TaqMan Low Density Arrays for miRNA expression profiling, and high throughput sequencing for gene expression quantification.ResultsWe identified 3 miRNAs and 272 genes as significantly differentially expressed at a 5% false discovery rate. Both the differentially expressed genes as well as the target genes of the ACM-specific miRNAs were found to be enriched in cell adhesion-related biological processes. Functional similarity and protein interaction-based network analyses performed on the identified deregulated genes, miRNA targets and known ACM-causative genes revealed clusters of highly related genes involved in cell adhesion, extracellular matrix organization, lipid transport and ephrin receptor signaling.ConclusionsWe determined for the first time the coding and non-coding transcriptome characteristic of ACM cardiac stromal cells, finding evidence for a potential contribution of miRNAs, specifically miR-29b-3p, to ACM pathogenesis or phenotype maintenance.Electronic supplementary materialThe online version of this article (10.1186/s12864-018-4876-6) contains supplementary material, which is available to authorized users.