Search results for "caffold"
showing 10 items of 470 documents
Engineering in-plane mechanics of electrospun polyurethane scaffolds for cardiovascular tissue applications
2021
Effective cardiovascular tissue surrogates require high control of scaffold structural and mechanical features to match native tissue properties, which are dependent on tissue-specific mechanics, function heterogenicity, and morphology. Bridging scaffold processing variables with native tissue properties is recognized as a priority for advancing biomechanical performance of biomedical materials and, when translated to the clinical practice, their efficacy. Accordingly, this study selected electrospinning on a rotating cylindrical target as an apparatus of broad application and mapped the relationship between key processing variables and scaffold mechanics and structure. This information was…
Polylactide biodegradable scaffolds for tissue engineering applications phase separation-based techniques
2011
One of the most reliable techniques for the preparation of biodegradable scaffoldssuitable for tissue engineering applications (e.g. regeneration of wounded/damagedtissues) is based on liquid/liquid phase separation of ternary solvent/antisolvent/polymersolutions. In particular, two phase separation protocols are examined here: ThermallyInduced Phase Separation (TIPS) and Diffusion Induces Phase Separation (DIPS). According to the former protocol, a thermodynamically stable polymeric ternarysolution is brought below its metastability/instability point (spinodal/binodal curve) byquench in a cooling medium: under opportune conditions, a foam-like structure is formedby nucleation and 3-D growt…
Performance of polyester-based electrospun scaffolds under in vitro hydrolytic conditions: From short-term to long-term applications
2019
The evaluation of the performance of polyesters under in vitro physiologic conditions is essential to design scaffolds with an adequate lifespan for a given application. In this line, the degradation-durability patterns of poly(lactide-co-glycolide) (PLGA), polydioxanone (PDO), polycaprolactone (PCL) and polyhydroxybutyrate (PHB) scaffolds were monitored and compared giving, as a result, a basis for the specific design of scaffolds from short-term to long-term applications. For this purpose, they were immersed in ultra-pure water and phosphate buffer solution (PBS) at 37 °
On the biomechanical function of scaffolds for engineering load-bearing soft tissues
2009
Replacement or regeneration of load-bearing soft tissues has long been the impetus for the development of bioactive materials. While maturing, current efforts continue to be confounded by our lack of understanding of the intricate multi-scale hierarchical arrangements and interactions typically found in native tissues. The current state of the art in biomaterial processing enables a degree of controllable microstructure that can be used for the development of model systems to deduce fundamental biological implications of matrix morphologies on cell function. Furthermore, the development of computational frameworks which allow for the simulation of experimentally derived observations represe…
Micro - Architectural Data Extraction for Electrospun Poly (Ester Urethane) Urea Scaffolds for Biomechanical Modeling.
2009
Problem: Soft tissue engineered applications have raised the need for accurate descriptions of tissue microstructure and their contributions to global mechanical behavior [1]. Accurate material image analysis is crucial to model engineered tissue biomechanics. The present study proposes a novel method to automatically collect micro-architectural data from electron micrographs (SEM) of electrospun poly (ester urethane) urea (PEUU). Methods: Sets of contiguous SEM images for electrospun PEUU scaffolds made using three mandrel collection tangential velocities (1.5, 4.5, 9.0 m/s) were analyzed. A combination of thresholding and morphological procedures enabled overlaps of fibers to be detected.…
O-102 Polymeric scaffold loaded with CD133+ BMDSCs for endometrial regeneration in Asherman’s syndrome
2021
Abstract Study question Can CD133+ bone marrow-derived stem cells (BMDSCs) loaded in polyethylene glycol diacrylate (PEGda) and gelatin divide and decidualize? Summary answer Biocompatible porous PEGda and gelatin scaffold provides a three-dimensional environment for CD133+ cells to attach, divide, and decidualize in vitro. What is known already Intrauterine adhesions (IUA) develop due to acquired damages in the endometrium resulting in partial to complete endometrial dysfunction in the Asherman syndrome. Previous works from our group have demonstrated the engraftment of CD133+ BMDSCs and its paracrine effect on endometrial proliferation, improved endometrial thickness and clinical outcome …
Rat Cardiac progenitor cells and their application in cell therapy
2015
cells and the subsequent heart failure. When the pharmacological approach no longer complies with the disease evolution, organ transplantation appears to be the only treatment able to rescue the patient life. Cell therapy promises to be clinically efficient and would allow circumventing many limitations of organ transplantation, such as organ low availability, major surgical procedures, high costs and longterm immunosuppression [1]. We designed porous Poly-Lactic Acid (PLLA) and Fibroin scaffolds to deliver CPCs in the heart, we isolated and characterized CPCs for the expression of c-Kit, MDR-1 and Sca-1 by flow cytometry, we tested their degree of differentiation in vitro studying the expr…
Human nasoseptal chondrocytes maintain their differentiated phenotype on PLLA scaffolds produced by thermally induced phase separation and supplement…
2018
Damage of hyaline cartilage such as nasoseptal cartilage requires proper reconstruction, which remains challenging due to its low intrinsic repair capacity. Implantation of autologous chondrocytes in combination with a biomimetic biomaterial represents a promising strategy to support cartilage repair. Despite so far mostly tested for bone tissue engineering, bioactive glass (BG) could exert stimulatory effects on chondrogenesis. The aim of this work was to produce and characterize composite porous poly(L-lactide) (PLLA)/1393BG scaffolds via thermally induced phase separation (TIPS) technique and assess their effects on chondrogenesis of nasoseptal chondrocytes. The PLLA scaffolds without or…
Ohjaava opetuskeskustelu suomalaisella viittomakielellä : tapaustutkimus kuuron oppilaan matematiikan opetuksesta
2014
Suomalaisen viittomakielen pro gradu –työssäni tarkastelen kuuron oppilaan viittomakielistä opetusta vuorovaikutuksen näkökulmasta. Tutkimusaineisto koostuu kahdesta matematiikan yksilöopetustunnista. Tutkimuksen tavoitteena on ollut selvittää, millaisia muotoja ohjaava opetuskeskustelu saa kuuron oppilaan suomalaisella viittomakielellä toteutetussa opetuksessa. Tapaustutkimuksen kautta yksilöidään ja luokitellaan myös viittomakielisen ohjaavan opetuskeskustelun osatekijöitä. Tutkimusaineiston analyysi perustuu Vygotskyn (1978) sosiokulttuuriseen teoriaan ja siihen liittyviin käsitteisiin oppimisen oikea-aikainen tukeminen ja lähikehityksen vyöhyke. Videotaltiointien analy…
Novel scaffold of natural compound eliciting sweet taste revealed by machine learning
2020
Abstract Sugar replacement is still an active issue in the food industry. The use of structure-taste relationships remains one of the most rational strategy to expand the chemical space associated to sweet taste. A new machine learning model has been setup based on an update of the SweetenersDB and on open-source molecular features. It has been implemented on a freely accessible webserver. Cellular functional assays show that the sweet taste receptor is activated in vitro by a new scaffold of natural compounds identified by the in silico protocol. The newly identified sweetener belongs to the lignan chemical family and opens a new chemical space to explore.