54 research outputs found
Fibers for hearts: A critical review on electrospinning for cardiac tissue engineering
Cardiac cell therapy holds a real promise for improving heart function and especially of the chronically failing myocardium. Embedding cells into 3D biodegradable scaffolds may better preserve cell survival and enhance cell engraftment after transplantation, consequently improving cardiac cell therapy compared with direct intramyocardial injection of isolated cells. The primary objective of a scaffold used in tissue engineering is the recreation of the natural 3D environment most suitable for an adequate tissue growth. An important aspect of this commitment is to mimic the fibrillar structure of the extracellular matrix, which provides essential guidance for cell organization, survival, and function. Recent advances in nanotechnology have significantly improved our capacities to mimic the extracellular matrix. Among them, electrospinning is well known for being easy to process and cost effective. Consequently, it is becoming increasingly popular for biomedical applications and it is most definitely the cutting edge technique to make scaffolds that mimic the extracellular matrix for industrial applications. Here, the desirable physico-chemical properties of the electrospun scaffolds for cardiac therapy are described, and polymers are categorized to natural and synthetic.Moreover, the methods used for improving functionalities by providing cells with the necessary chemical cues and a more in vivo- like environment are reported
Engineered Biomaterials to Enhance Stem Cell-Based Cardiac Tissue Engineering and Therapy
Cardiovascular disease is a leading cause of death worldwide. Since adult cardiac cells are limited in their proliferation, cardiac tissue with dead or damaged cardiac cells downstream of the occluded vessel does not regenerate after myocardial infarction. The cardiac tissue is then replaced with nonfunctional fibrotic scar tissue rather than new cardiac cells, which leaves the heart weak. The limited proliferation ability of host cardiac cells has motivated investigators to research the potential cardiac regenerative ability of stem cells. Considerable progress has been made in this endeavor. However, the optimum type of stem cells along with the most suitable matrix-material and cellular microenvironmental cues are yet to be identified or agreed upon. This review presents an overview of various types of biofunctional materials and biomaterial matrices, which in combination with stem cells, have shown promises for cardiac tissue replacement and reinforcement. Engineered biomaterials also have applications in cardiac tissue engineering, in which tissue constructs are developed in vitro by combining stem cells and biomaterial scaffolds for drug screening or eventual implantation. This review highlights the benefits of using biomaterials in conjunction with stem cells to repair damaged myocardium and give a brief description of the properties of these biomaterials that make them such valuable tools to the field.Anwarul Hasan acknowledges the startup grant and the University Research Board (URB) grant from American University of Beirut, Lebanon, and the National Council for Scientific Research (CNRS) grant, Lebanon, as well as the Farouk Jabre interdisciplinary research award. Arghya Paul acknowledges the University of Kansas New Faculty General Research Fund for support and assistance with this work. The authors also acknowledge an investigator grant provided by the Institutional Development Award (IDeA) from the National Institute of General Medical Sciences (NIGMS) of the NIH Award Number P20GM103638-04 (to A.P.). R.W. acknowledges the financial support from NIGMS (NIH, T32-GM008359) Biotechnology Predoctoral Research Training Program
Energy-dependent collision-induced dissociation of lithiated polytetrahydrofuran: Effect of the size on the fragmentation properties
Development and characterization of fibrin and hyaluronan coated biodegradable polyurethane films
grantor:
University of TorontoA new family of biodegradable elastomeric polyurethane blends was created. These novel materials were coated with thin layers of fibrin (and hyaluronan (HA)). The effects of varying blend composition on the morphology, mechanical properties and degradation rate were assessed. The polyurethane blends, which degrade on the order of months to years, were found to have mechanical properties similar to those of a commercially available polyurethane wound dressing. Both fibrin and fibrin/HA coatings were achieved on the blends. The surface topology of the polyurethane surfaces appeared to affect coating cohesiveness. This was particularly true for the fibrin coatings, which demonstrated a less uniform appearance than the fibrin/HA coatings. The bi-laminar wound dressings developed in this work could be particularly applicable for skin graft donor site applications, where speed and quality of heating are extremely important factors.M.A.Sc
Diagnosis and treatment of anterior uveitis: optometric management
Jennifer S Harthan,1 Dominick L Opitz,2 Stephanie R Fromstein,1 Christina E Morettin3 1Cornea Center for Clinical Experience, 2Ophthalmology Services and Practice Development, 3Urgent Eye Care Service, Illinois College of Optometry, Chicago, IL, USA Abstract: Anterior uveitis encompasses inflammation of the iris and/or ciliary body and is one of the most common types of ocular inflammation that primary eye care practitioners will encounter. Anterior uveitis may be caused by a variety of etiologies, including infectious, noninfectious, and masquerade diseases. The short-term and long-term treatment of uveitis should include the evaluation of location, duration, pathology, and laterality, in addition to presenting signs and symptoms of the disease. A complete review of systems, thorough examination, and laboratory testing, may assist the practitioner in narrowing the list of possible causes for the uveitis. This is imperative as once a list of diagnoses has been made, a targeted approach to treatment can be pursued. Keywords: anterior uveitis, iritis, inflammatio
Diagnosis and management of meibomian gland dysfunction: optometrists' perspective
Dominick L Opitz,1 Jennifer S Harthan,1 Stephanie R Fromstein,1 Scott G Hauswirth2 1Department of Clinical Education, Illinois College of Optometry, Chicago, IL, 2Minnesota Eye Consultants, Minneapolis, MN, USA Abstract: Meibomian gland dysfunction (MGD) is commonly encountered among eye care professionals. Our understanding of the pathophysiology for the development of MGD has greatly expanded in recent years, which helped increase awareness of the disease. Despite increased awareness, it is essential for eye care professionals to make a conscious effort to properly examine the meibomian glands through gland expression even for asymptomatic patients. At minimum, early management should include patient education and supportive therapy such as warm compresses, lid hygiene, and gland expression. As patients become more symptomatic and as the ocular surface becomes more affected, employing additional therapeutic management is recommended and may include oral omega-3 essential fatty acids, topical azithromycin, oral tetracycline, and topical anti-inflammatories to improve clinical signs and patient comfort. In addition to treatment of MGD, clinicians should be mindful of the comorbid conditions of MGD and simultaneously manage them in conjunction of MGD treatment. Keywords: meibomian gland dysfunction, dry eye, blepharitis, ocular surface diseas
Synthesis and characterization of novel biodegradable epoxy-modified polyurethane elastomers
Biodegradable aliphatic thermoplastic polyurethane based on poly(ɛ-caprolactone) andL-lysine diisocyanate
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