23 research outputs found
Endogenous Constitutions
No full textWe present a theory of the choice of alternative democratic constitutions, a majoritarian or a consensual one, in an unequal society. We show that a consensual system turns out to be preferred by society when "ex ante" income inequality is relatively low, while a majoritarian system is chosen when income inequality is relatively high. We also find that consensual democracies should be expected to be ruled more often by centre-left coalitions while the right should have an advantage in majoritarian constitutions. The implications for the relationship between inequality and redistribution are discussed. Historical evidence and a cross-sectional analysis support our results. Copyright � The Author(s). Journal compilation � Royal Economic Society 2009.
Development of biologic scaffolds for reconstructive surgery from decellularized human skeletal muscle
No full textPreparation of a 3d complex scaffold from homologous omentum for recellularization with autologous cells
No full textA COMPLEX ECM 3D SCAFFOLD WITH VASCULAR CHANNELS BY DECELLULARIZATION OF HUMAN AND RAT OMENTUM
No full textINTRODUCTION: lack of vascular network affects the long term survival in grafts of considerable size, while flaps have limited availability and imply co-morbidity. A bioengineered graft with organized vascular channels may overcome this limit: decellularized omentum was investigated as potential source of ECM 3D scaffold with preformed vascular network.
MATERIALS AND METHODS: Rat and human omentum samples were de-cellularized with a modified protocol for adipose tissue. At each step samples were collected for histological and immunohistochemical assessment of the effectiveness of the protocol.
RESULTS: Histological and IHC samples showed effective cell removal with preservation of ECM structure and composition. Blood vessel walls in particular appeared intact, maintaining their general architecture.
CONCLUSION: Omentum decellularization appears as a feasible strategy to obtain a scaffold with complex ECM and a preserved flap-like vascular channel network, which may support and stimulate guided cell growth in vitro or in vivo. It could represent an innovative option for more effective closure of soft tissue defects
Preparation of a 3D scaffold derived from xenologous omentum for autologous recellularization.
No full textDecellularization of rat and human omentum to develop novel scaffolds to be recellularized with adipose derived stem cells. In: LXV Congresso della Società Italiana di Anatomia e Istologia, Padova, 2011.
No full textDecellularization of rat and human omentum to develop novel scaffolds for regenerative medicine. In: 34° Congresso Nazionale della Sopcietà Italiana di Istochimica. San Benedetto del Tronto, 7-9 giugno 2011.
No full textDecellularized omentum as novel biologic scaffold for reconstructive surgery and regenerative medicine
No full textHomologous tissues, such as adipose tissue, may be an interesting source of acellular scaffolds, maintaining a complex physiological three-dimensional (3D) structure, to be recellularized with autologous cells. The aim of the present work is to evaluate the possibility of obtaining homologous acellular scaffolds from decellularization of the omentum, which is known to have a complex vascular network. Adult rat and human omenta were treated with an adapted decellularization protocol involving mechanical rupture (freeze-thaw cycles), enzymatic digestion (trypsin, lipase, deoxyribonuclease, ribonuclease) and lipid extraction (2-propanol). Histological staining confirmed the effectiveness of decellularization, resulting in cell-free scaffolds with no residual cells in the matrix. The complex 3D networks of collagen (azan-Mallory), elastic fibers (Van Gieson), reticular fibers and glycosaminoglycans (PAS) were maintained, whereas Oil Red and Sudan stains showed the loss of lipids in the decellularized tissue. The vascular structures in the tissue were still visible, with preservation of collagen and elastic wall components and loss of endothelial (anti-CD31 and -CD34 immunohistochemistry) and smooth muscle (anti-alpha smooth muscle actin) cells. Fat-rich and well vascularized omental tissue may be decellularized to obtain complex 3D scaffolds preserving tissue architecture potentially suitable for recellularization. Further analyses are necessary to verify the possibility of recolonization of the scaffold by adipose-derived stem cells in vitro and then in vivo after re-implantation, as already known for homologus implants in regenerative processes
Decellularization of rat and human omentum to develop novel scaffolds to be recellularized with adipose derived stem cells
No full textHigh-risk and low-risk gastric cancer areas in Italy and its association with microsatellite instability
No full textPurpose: The different pathological characteristics and prognoses between gastric cancer patients coming from high-risk (group A) and low-risk (group B) areas of Italy were analyzed. We investigated a suspected difference in microsatellite instability (MSI) between these two groups. Methods: MSI analyses of 452 gastric cancer patients were performed using five quasimonomorphic mononucleotide repeats NR-21, NR-24, NR-27, BAT-25, and BAT-26. MSI analysis was done by PCR usage. An allelic profile of these five mononucleotides was detected on an automated DNA sequencer ABI PRISM 3100 Genetic Analyser. Data were analyzed according to high-risk and low-risk gastric cancer areas. Results: MSI was observed in 23.9 % of all gastric cancer patients studied. Patients from group A showed a higher rate of MSI (28.4 %) than from group B (13.5 %) (p < 0.001). We analyzed this association together with tumor location and Lauren classification: A nonsignificant differences were seen when analyzing cardia and non-cardia tumors (p = 0.854) but significant for Lauren histotype (p = 0.028). There was no statistical difference in survival between high-risk and low-risk areas (p = 0.437), with a nonsignificant trend for better survival in the high-risk group, especially when measured over a longer period of time. Analyzing MSI or MSS in these groups, the survival curves were almost the same. Conclusions: A higher frequency of MSI in patients coming from high-risk areas may help explain geographical differences in gastric cancer. The trend of better survival in high-risk areas may be due to a higher rate of MSI gastric cancer patients
