Recent Developments in Bioengineering (PDF)

Bioengineering Recent Developments Bioengineering MPS Department | FEU Institute of Technology  Bioengineering Recent Developments in Pacemaker Technology MPS Department | FEU Institute of Technology  OBJECTIVES Discuss the history of pac...

Bioengineering Recent Developments Bioengineering MPS Department | FEU Institute of Technology  Bioengineering Recent Developments in Pacemaker Technology MPS Department | FEU Institute of Technology  OBJECTIVES Discuss the history of pacemaker; Discuss how a pacemaker works; and Discuss the recent innovations in the pacemaker technology.  1 THE HEART ▪ Look for a partner. ▪ Measure each others heart rate by placing your index and middle finger to your partner’s wrist. ▪ Use a timer. Source: heartzones.com Source: texasheart.org  Sinus node Atrioventricular node Purkinje fibers Source: heartzones.com  2 HISTORY OF THE PACEMAKER A small device placed under the skin in the chest to help control the heartbeat. Used to help the heart beats regularly when having an irregular heartbeat (arrhythmia), particularly a small one. Can be implanted temporarily to treat slow heartbeat after a heart attack, surgery or medication overdose. Source: sciencemag.org Danish physicist Nickolve Abildgaard studied the effects of electrical energy when applied to the body. He reanimated a dead hen by placing the electrodes across the chest. Source: google.com Marie Francois Xavier Bichat and Nysten Were able to make hearts of decapitated humans beat again using electric current Source: google.com Rudolph Alber von Kollicker “Action currents” of the heart Electric current was produced with each beat of a frog’s heart Source: livescience.com Duchenne de Boulogne Successfully resuscitated a child who had drowned by attaching electrode to the leg Source: google.com 1926: MARK COWLEY LIDWILL “cardiac muscle could be made to contract through electrical stimulation” “electrical device to resuscitate patients in whom the conducting system failed” Transcutaneous, using an insulated needle 80 – 120 pulse/min, 1.5 – 120 volts Source: sydney.edu.au 1932: ALBERT HYMAN Reviving the “stopped heart” by “intracardial therapy” Designed a device powered by a spring- wound hand-cranked motor called “artificial pacemaker” Revived 14 out of 43 animals Source: sydney.edu.au 30, 60 or 120 pulse/min FIRST MAINS-POWERED PORTABLE PACEMAKER Source: sydney.edu.au Cardiac surgeon Wilfred Bigelow and John Callaghan Used hypothermia (lowering of body temperature) to reduce metabolism and produce bradycardia (slow heart rhythm) and asystole (flatline) to permit cardiac surgery Problem encountered: Re-warming could not restore cardiac contraction Thus, the world would know John Hopps, an electrical engineer. Source: bcmj.org ▪ 30 cm in length ▪ Vacuum tubes to generate pulses ▪ Powered by 60-Hz household current ▪ Used transvenous catheter electrodes Rune Elmqvist (medical graduate who pursued engineering) and Ake Senning (cardiac surgeon) Ni-Cd batteries Electronic circuit Coil recharging antenna Encapsulated in Araldite (epoxy resin) – biocompatible 55 mm (d) x 16 mm (t) Source: implantable-device.com  ARNE LARSSON Hospitalised with complete heart block and Stokes-Adams attacks for 6 months 20 to 30 attacks daily Senning recounts: “On the 8th October 1958, in the evening, when there were no extra people in the theatre, I implanted the first pacemaker.” Source: alchetron.com  ARNE LARSSON ▪ First implant lasted for 3 hours ▪ Second implant lasted for 1 week ▪ Died at the age of 88 in 2001 from unrelated causes ▪ Underwent a total of 26 pacemaker replacement procedures Source: alchetron.com He founded the Canadian Medical and Biological Engineering Society Became part of discoveries of: Devices to treat blindness and muscular disabilities Machines for respiration Cathode-ray displays for cardiac operating rooms Cardioscopes for post-operative monitoring Heart rate monitors for sports medicine In 1984, he had his first pacemaker implanted Source: bcmj.org followed by a replacement 13 years later.  3 THE21STCENTURY PACEMAKER  Pulse Generator Regulates the rate of electrical pulses sent to the heart Leads (electrodes) 1 to 3 flexible wires placed in Source: mddionline.com the chambers and deliver Source: mddionline.com electrical pulses to adjust the heart rate Source: mddionline.com  Li-I, Cd-Ni, nuclear Titanium Materials of Constructions: Silicon Pharnacologically inert semiconductors Nontoxic Sterilizable Functional in environmental conditions in the body Metal alloy with polymer (polyurethane) insulation Source: mddionline.com  Works only when needed Newer pacemakers have sensors detecting body motion or breathing rate Source: texasheart.org SINGLE CHAMBER Carries electrical impulses to the right ventricle DUAL CHAMBER Carries electrical impulses to the right ventricle and right atrium to help control the timing of contractions between the two chambers BIVENTRICULAR Aka cardiac resynchronization therapy Treats heart failure by stimulating the left and right ventricles Source: google.com Source: hopkinsmedicine.org Source: mddionline.com Source: 21stcentech.com  4 NEW DEVELOPMENTS IN THE PACEMAKER TECHNOLOGY ▪ Engineers from University of Texas at San Antonio ▪ Smaller batteries ▪ Designed to reduce the power consumption, thus, extending battery life without limiting device functionality Source: mddionline.com ▪ Researchers from Rice University ▪ Designed to harvest energy wirelessly from radio-frequency radiation by an external battery pack ▪ No leads needed ▪ Adjustable pacing by controlling the power transmitted Source: mddionline.com ▪ Bath University, UK ▪ Prediction of neuron behavior and small neural devices to reverse effects of heart failure ▪ Design pacemakers that can mimic neurons allowing the device to respond accurately Source: mddionline.com ▪ Harvard’s School of Engineering and Applied Sciences ▪ Smallest radio receiver from atomic-scale defects in pink diamonds ▪ Transmission of electrical pulses to receiver using radio waves ▪ Green light emitted from a laser powering the electrons Source: mddionline.com ▪ University of Buffalo ▪ Heart as a natural power source ▪ Covert vibrational energy of heartbeat to electrical energy to power the pacemaker Source: mddionline.com ▪ McEwen Center for Regenerative Medicine ▪ Human pluripotent stem cells to pacemaker cells conducting electrical impulses ▪ Biological pacemaker implant Source: mddionline.com ▪ Eugenio Cingolani, MD and Joshua Gold Haber, MD from Cedars-Sinai Heart Institute ▪ Gene-therapy turning patient’s own heart cells into pacemaker cells ▪ Delivering a gene directly into the heart Source: mddionline.com  Bioengineering Recent Developments in Vaccine Delivery MPS Department | FEU Institute of Technology  OBJECTIVES Discuss the mechanisms of the given research study; and Analyze how bioengineering and engineering principles are applied in the research. Medicines that trains the body’s immune system so that it can fight disease-causing pathogens it has not come into contact with before. Vaccines contain certain molecules from the pathogen called ANTIGENS. Currently, there are available vaccines against 23 diseases. The immune system uses tools to fight infection including the white (immune) blood cells which consist of the following: 1. Macrophages – swallow up and digest germs, dead, drying cells leaving behind parts of the invading germs which is then attacked by the body. 2. B-lymphocytes – defensive WBC that produces antibodies to attack the antigens left by the macrophages. 3. T-lymphocytes – defensive WBC that attack infected cells. TYPE OF DESCRIPTION ADVANTAGE DISADVANTAGE DISEASES VACCINE Cannot be given to people with weakened immune Excellent simulation for Measles, Mumps, Weaker, systems such as those the immune system that Rubella, Varicella Live asymptomatic undergoing chemotherapy or can result to lifelong (chickenpox), Attenuated form of the HIV treatment immunity with just one or Influenza, pathogen two doses Rotavirus Must be refrigerated at all times to preserve life Can be freeze dried and Uses pathogen stored easily Inaccurate simulation of the killed with heat Polio, Hepatitis A, Inactivated live version, thus more doses or chemicals or No risk of pathogen Rabies or booster shots are needed its dead cells mutating back into its disease-causing form TYPE OF DESCRIPTION ADVANTAGE DISADVANTAGE DISEASES VACCINE Hepatitis B, Influenza, Haemophilus Uses essential parts (specific Influenzae Type B Less side Not applicable to all Subunit protein or carbohydrate) of the (Hib), Pertussis, effects pathogens pathogen only Pneumococcal, Human Papillomavirus, Meningococcal For pathogens with antigens disguised by polysaccharide coat Haemophilus Conjugate Conjugate vaccines link these Influenzae Type B (Hib) antigens to pathogens recognizable by the immune system Contains toxoid, weakened Toxoid toxins, released by toxin- Diphtheria, Tetanus producing pathogens VACCINATION the act of introducing a vaccine into the body. Can be done by injection, orally, or nasally IMMUNIZATION the process by which a person or animal becomes protected against a disease. Biomimetic Micromotor Enables Active Delivery of Antigens for Oral Vaccination Wei, X., Gastelum, M.B., Karshalev, E., De Avila, B.E.F., Zhou, J., Ran, D., Angsantikul, P., Fang, R.H., Wang, J. & Zhang, L. (2019) Department of NanoEngineering and Chemical Engineering Program, University of California San Diego, La Jolla, CA 92093, USA Enhance vaccine potency, high loading capacity, retention, and sustained release characteristics  Fabricate a self-propelling motor toxoid for oral particulate antigen delivery In this study, antigens were delivered to the lining of the small intestine. Source: Wei, X., 2019 1. Magnesium (Mg) microparticles are coated with asymmetrical layer of titanium dioxide (TiO2). 2. The Mg-TiO2 particle is coated with toxin-inserted RBC membrane, the antigenic material. 3. The particle is coated with the mucoadhesive chitosan. 4. The whole toxoid is coated with pH-sensitive enteric coating. Source: Wei, X., 2019 1. The MT is ingested orally. 2. The MT travels from the mouth to the stomach. 3. As the MT passed through the stomach to the intestine, the pH starts to increase. 4. The enteric coating dissolves as the pH in the intestine reaches 5.5 (and above) exposing the Mg- TiO2 particle. 5. The Mg reacts with the water in the intestinal fluid and releases H2 gas. 6. As H2 gas is released, the MT moves and self-propel to the intestinal lining. 7. The MT attaches itself to the lining because of the Source: Wei, X., 2019 mucoadhesive chitosan. 8. The antigen payload is delivered.  The formulation has no effect on the cell viability when tested after 3 days of incubation. The MT formulation was highly present in the intestinal lining unlike with static microparticles mainly found in the stomach. The production of anti-toxin titer increased by approximately one order of Source: Wei, X., 2019 magnitude. ✓ Increase payload retention ✓ Enhanced delivery localization ✓ Enhanced generation of mucosal immunity Mucosal immunity - when vaccines prompt response from antibodies in the mucous membrane instead of stimulating antibodies in the blood WEI, X. (2019). Biomimetic Micromotor Enables Active Delivery of Antigens for Oral Vaccination. HHS Public Access, Nano Lett., 19 (3): 1914-1921. doi: 10.1021/acs.nanolett.8b05051 Understanding How Vaccines Work. Adapted from the National Institute of Allergy and Infectious Diseases, Understanding Vaccines https://www.niaid.nih.gov/research/how-vaccines-work PAVLOVIC, M. (2015). Bioengineering A Conceptual Approach. Springer, Switzerland. STRUGIS, K. (2017). 8 New Developments That Could Revolutionize Pacemakers. Retrieved from https://www.mddionline.com/8-new-developments-could- revolutionize-pacemakers Image sources: mddionline.com heartzones.com texasheart.org sciencemag.org livescience.com sydney.edu.au 21stcentech.com implantable-device.com