Biomed Unit 1- How to Fight Infection

Biomed: Medical Interventions (PLTW) Unit 1- How to Fight Infection 1.1- Mystery Infection Vocabulary Medical Interventions Any measure whose purpose is to improve health or alter the course of disease. Outbreak A sudden rise in the incident of disease. Pathogen A specific causative agent of disease. Bioinformatics The collection, classification, storage, and analysis of biochemical and biological information using computers especially as applied in molecular genetics and genomics. Genome The complement of an organism’s genes; an organism's genetic material. BLAST Basic Local Alignment Search Tool, to compare the nucleotide of the pathogen with the database to determine the matching organism. GenBank Database A publicly available molecular database containing nucleotide and amino acid sequences for hundreds of thousands of organisms. Antibody A protein secreted by plasma cells (differentiated B cells) that bind to a particular antigen and marks it for elimination. Antigen A macromolecule that elicits an immune response by lymphocytes. Booster An additional dose of a vaccine used to “boost” the immune system. They boost the levels of antibodies you have. Concentration The amount of specified substance in a unit amount of another substance. Solvent A substance, usually a liquid, capable of dissolving another substance. Solution A homogeneous mixture of 2 or more substances, which may be solids, liquids, gasses, or a combination. Enzyme- Linked Immunosorbent Assay (ELISA) A quantitative in vitro test for an antibody or antigen present in the body. Enzyme A protein serving as a catalyst, a chemical agent that changes the rate of reaction without being consumed. Qualitative Results Indicate whether a patient is positive or negative for the presence of the antigen or antibody. Quantitative Results Determine how much of the detected substance is present. ● Medical Intervention categories- Interventional procedures ex. Appendectomy, diagnostic ex. X-ray, assistive devices ex. Wheelchair, drugs ex. Albuterol inhaler, and behavioral ex. Exercise routine. ● Containing Infection- Contact webs help scientists determine how the infection or disease may have been spread and help to contain the outbreak of the disease through isolation and sanitation. ● Human genome project- A project, started in 1990, to map the complete genetic layout of a human being, they determined the complete nucleotide sequence of DNA of each human chromosome. This helps us to identify, treat, and contain diseases. ● DNA Sequencing- How scientists determine the precise order of nucleotides within a DNA Molecule. Bacterial Meningitis Physical Effects- poor coordination, dizziness, memory loss, headaches, weakness, hearing loss, vision problems, damage to membranes on brain and spinal cord. Meningitis affects the meninges, the membranes surrounding the brain and spinal cord. Treatment- Intravenous antibiotics, corticosteroids. Treatment must be administered as soon as possible to reduce the risk of permanent damage to the brain and spinal cord. Antibiotics Antigens are molecules that are foreign to the body and can include bacteria, viruses, and fungi. Antibodies are specific proteins that are produced in response to invading antigens, they seek out and attach to invaders, flagging them for destruction by the immune system. → Antibodies are extremely specific to the antigens they attack. The Immune system is the body's system of fighting off invaders. B-lymphocytes, a type of WBC help to fight infection, they are present in the blood and lymph nodes. 1.2- Antibiotic Treatment Vocabulary Antibiotics A substance produced by or derived from a microorganism and able in dilute solution to inhibit or kill another microorganism. Zone of Inhibition The clear area where the bacteria were not able to grow or survive. Antibiotic Resistant Resistance to one or more antibiotics usually due to additional genetic information. Nucleoid The area of a gene that contains DNA. Plasmid A small ring of DNA that carries accessory genes separated from those of the bacterial chromosome. Conjugation The one-way transfer of DNA between bacteria in cellular contact. Transformation The uptake and expression of foreign DNA by a cell. Transduction The transfer of genetic material from one organism to another by a genetic vector. Gram Negative Vs. Gram Positive ● GP has thick cell walls composed of peptidoglycan or murein ● GP stains positive ● GP has cell walls that contain chains of teichoic acid that extend from the plasma membrane through the cell wall ● GN has thin walls of peptidoglycan ● GN stains pink ● GN has an outer membrane of lipopolysaccharide Antibiotic Types ● Penicillin ○ Stop peptidoglycan cross linking to weaken/ breakdown cell walls ○ Best for Gram positive ○ Kills cells ● Fluoroquinolone ○ Stops DNA replication ○ Prevents untwisting of DNA ○ Broad Spectrum ● Sulfonamides ○ Binds to enzymes that metabolize folate into folic acid ○ Inhibit ○ Broad spectrum ● Tetracycline ○ Stop protein synthesis ○ tRNA cant join with mRNA to make amino acid chain ○ Broad spectrum Mechanisms of Antibiotic Resistance ● Genetic Mutation ○ A change in DNA that can cause a change in the gene product that is targeted. ● Destruction/inactivation ○ Some bacteria have genes which produce enzymes that chemically degrade the antibiotic, making them ineffective. ● Efflux ○ Efflux pump is a channel that exports materials out of the cell through an active process. Some bacteria can become antibiotic resistant through the efflux pump pumping out antibiotics and preventing it from collecting in the cell. ● Genetic Transfer- Conjugation ○ Aided by circular DNA (plasmids) which replicates without the chromosome. A pillis forms between two cells allowing the plasmid copy to go from one cell to another, transferring the antibiotic resistance. ● Genetic Transfer- Transformation ○ Genes are transferred as naked DNA from one cell with the antibiotic resistant gene to another normal cell. ● Genetic Transfer- Transduction ○ Bacteria DNA is transferred from one to another via a virus that infects the bacteria cell and serves as a vector for the DNA. 1.3- The Aftermath Vocabulary Cochlear Implant An electrical prosthetic device that helps people with sensorineural hearing loss recognize sounds. It is composed of a microphone and speech processor that converts the sound waves into electrical signals that are transmitted into the implanted electrode(s) in the cochlea. Audiologist A healthcare specialist in treating patients with hearing loss or related disorders. Sound Mechanical energy that is transmitted by longitudinal pressure waves. Crest Highest point of a wave. Trough Lowest point of a wave. Amplitude The measure of how much energy a wave carries. Wavelength The distance from one crest to another. Pitch Determined by frequency, the degree of highness or lowness of a tone. Frequency How rapidly the sound waves vibrate each second. Hertz Vibrations per second. Intensity Loudness, determined by amplitude. Amplitude Amount of energy in a wave. Decibels How sound intensity is measured. Pinna External structure that directs sound to the inner ear. Auditory Canal Transmit sound from pinna to tympanic membrane. Eustachian Tube Ventilates the middle ear space, ensuring that its pressure remains at a normal pressure. Ossicles Transmits sounds from air to cochlea. Tympanic Membrane Thin layer of tissue that receives sound vibrations and transmits them to the ossicle. Cochlea Changes the vibrations of the cochlear liquids and structures into a neural signal. Sensory Hair Cell Amplify sound waves and convert auditory information to the brain stem. Cochlear Nerve Brings auditory information from cochlea to the brain. Oval Window A membrane covered opening that leads from the middle ear. Vestibule Detect changes in gravity and linear acceleration. Vestibular Nerve Transforms vestibular information to an egocentric frame of reference. Audiometer Used to measure a subject's hearing sensitivity. Threshold The softest sound a subject can hear. Audiogram A graphic representation of the relation of vibration frequency and the minimum sound intensity for hearing. Hearing Tests ● Rinne Test ○ Evaluates hearing loss by comparing air conduction to bone conduction. ● Speech-in-Noise Test ○ Assess sensorineural hearing loss usually in active duty soldiers. ● Pure Tone Test ○ Tests air conduction by finding the quietest sound you can hear at different frequencies. 1.4- Vaccination Vocabulary Vaccine A harmless variant of a pathogen that stimulates a host's immune system to mount defenses against the pathogen. Vaccination A procedure that presents the immune system with a harmless variant of a pathogen, thereby stimulating the immune system to mount a long term defense against the pathogen. Recombinant DNA Technology The process of cutting and recombining DNA fragments. Plasmids A small ring of DNA that carries additional genes that are separate from those in the chromosomes. Vectors Carries and moves genetic material. Genes A part of DNA that code for a specific protein to be produced. Restriction Enzyme An enzyme that recognizes and cuts specific sequences of DNA. DNA ligase An enzyme that helps to join the ends of DNA strands. Vaccines and Immune System After the vaccine is administered ● Immune system identifies the antigens ● Immune system develops proteins that circulate the blood to help fight the infection ● Body stockpiles antibodies so they are available to fight off the disease once exposed Immunities ● Innate- Born with, genetic ● Adaptive/ active- exposed to or vaccinated against ● Passive- passed from mother to baby ● Herd- everyone around you is protected Characteristics of an Effective Vaccine ● Low levels of side effects and toxicity ● Protect against exposure to natural or wild forms of the pathogen ● Stimulates antibody and cell mediated response ● Have long term, lasting effects producing immunological memory ● Require minimal boosters ● Easy to administer with long shelf life Vaccine Types ● Killed or inactive ○ Can't multiply and it contains recognizable antigens on skin but requires a larger dose and possible additional boosters. ● Live Attenuated ○ Long lasting and requires fewer boosters however, small chance of disease agent mutating back to pathogen strain. ● Genetically Modified ○ Provokes an immune response however copy and transfer mistakes can happen. ● Naked DNA ○ Small chance of replication as it is just DNA but it may infect the host. Epidemiology Case Control Study ● Retrospective ● Looks at old resources ● People are similar Cohort Study ● Prospective ● Ongoing