Intro to Biomedical Engineering Quiz 5 Review EXAM WITH CORRECT ANSWERS 2024.

What is the difference between tissue engineering and regenerative medicine? Be able to distinguish between the two. - answer-TE aims to reproduce tissue in vitro, while regenerative medicine aims to repair tissue in vivo. How is an artificial organ different from a tissue engineered one? - answer-Artificial organs: made of polymers and metals (and sometimes ceramics). Tissue engineering: might use a polymer or ceramic as a scaffold, but designed such that in the long-term the scaffold will degrade, leaving neo tissue. Regenerative medicine: typically done inside the body, with or without a scaffold What are some examples of artificial organs? - answer-Total artificial heart, Ventricular assist device, Prosthetics (artificial limbs), Contact lenses, Bionics (eyes and ears, others), Colostomy bag, Artificial hips and knees What are some tissues/organs/structures in the human body that can regenerate themselves? - answer-Skin has limited ability to regenerate, the liver can regenerate if only 25% of it remains. The human lens can also regenerate. What is the motivation for tissue engineering (i.e., why so much interest?)? - answer-Many organs do not repair/regenerate themselves. Transplant demand is much higher than transplant supply When was the first official tissue engineering approach carried out? - answer-1970s by W.T. Green, placed cartilage cells (chondrocytes) on bone spicules (small chunks) to try to regrow cartilage. What is a nude mouse? - answer-a laboratory mouse from a strain with a genetic mutation that causes a deteriorated or absent thymus, resulting in an inhibited immune system due to a greatly reduced number of T cells. What was the "auriculosaurus"? - answer-A lab mouse with an ear on its back. What is a tissue engineering scaffold and why is it needed? - answer-Act as templates for tissue regeneration, to guide the growth of new tissue. What are three materials for scaffolds that have been used to try to regenerate tissue? - answer-PLGA (suture material), Alginates (isolated from seaweed, used in wound dressings), Fibrin ("fibrin glue"), Chitosan Collagen/glycosaminoglycans(naturally occurring), Hydrogels based on polyethylene glycol (PEG) What are three different techniques used to create tissue engineering scaffolds? - answer-Gas foaming, emulsification, freeze-drying, 3D bioprinting. Why are stem cells important for regenerative medicine/tissue engineering? - answer-Because they are grown easily in the laboratory and appear to be capable of becoming any type of cell. What is a stem cell? Where are they isolated from? What are the differences between embryonic and adult stem cells? Where can adult stem cells be found? - answer-An unspecialized cell that can renew itself indefinitely and develop into more mature, specialized cell. Adult stem cells can be found in hematopoietic stem cells, neuronal stem cells mesenchymalstem cells (also found in bone marrow), epithelial stem cells, skin stem cells. What are the differences between totipotent, pluripotent, and multipotent? - answer-totipotent, meaning that its potential is total. pluripotent— they can give rise to many types of cells but not all types of cells necessary for fetal development. From where are embryonic stem cells isolated? - answer-stem cells that come from embryos that are three to five days old. Which stem cells give rise to: red blood cells? Cartilage cells? Nerve cells? Epidermal cells? - answer-Hematopoietic Stem Cells = red blood cells. Mesenchymalstem cells = cartilage cells. Neural Stem Cells = nerve cells. Skin Stem Cells = epidermal cells. What are the two main types of cells found in skin? - answer-Epidermal cells and follicular cells What is cell expansion? - answer-In order for stem cells, or even fully differentiated cell populations to be truly beneficial or useful, either therapeutically, as drug screening tools, or for core research purposes, expansion of cells is prerequisite. What are two tissue engineering products that the FDA has approved to date? - answer-Apligraf and carticel What was the first FDA approved tissue engineering scaffold/product and when approved? - answer-Integra -artificial skin composed of silicone and collagen/glycosaminoglycans, FDA approved in 1996. What is Apligraf composed of? - answer-collagen matrix with fibroblasts and keratinocytes and 40 bioactive factors. When was MACI FDA approved? - answer-FDA approved in December of 2016. What is the difference between ACI (aka Carticel) and MACI (aka Vericel)? - answer-matrix-induced autologous cartilage implant Why did Vericel close its EU manufacturing site? - answer-Wasn't economical/profitable (poor sales), mainly because of Europe's cash-strapped health care system (reimbursement issues). What is the single biggest challenge to tissue engineering? - answer-vascularization When did the U.S. essentially begin to start regulating drugs? - answer-1906 When did the U.S. start regulating medical devices? - answer-1976 What are the main differences between Class I, Class II, and Class III devices. - answer-Class 1 devices pose the least amount of risk to consumers. These low-risk devices, such as oxygen masks or surgical tools, are subject to "general controls." Class 2 devices pose more risk to consumers than do Class 1 devices. Therefore, Class 2 devices are subject to special controls in addition to general controls. Class 3 devices support or sustain life, are implanted in the body, or have the potential for unreasonable risk of illness or injury. Examples include pacemakers, breast implants, and HIV diagnostic tests. As a result, Class 3 devices require premarket approval. What does it mean by the "510(k)" pathway? - answer-Requires proof that the devices is substantially equivalent (SE) to a legally marketed device that is not subject to Premarket Approval (PMA). Does the FDA "approve" Class II devices? - answer-Yes, if it is not proven that the device is substantially equivalent to another device already on the market. Does the FDA "approve" Class III devices? - answer-Yes, all class III devices must go through premarket approval. What does PMA mean and which class of devices is it used to describe? - answer-PMA refers to the scientific and regulatory review necessary to evaluate: the safety and effectiveness of Class III devices or devices that were found not substantially equivalent to a Class I or II predicate through the 510(k) process.