Medical Interventions Unit 1 Slides PDF

Medical Interventions Unit 1 slides Overview 1.1 The mystery Infection 1.2 Antibiotic Treatment 1.3 Aftermath: hearing loss 1.4 Vaccination Unit 1 takes place on a college campus where we are trying to identify and contain an unknown pathogen that has broke out on campus. We will contract trace, u...

Medical Interventions Unit 1 slides Overview 1.1 The mystery Infection 1.2 Antibiotic Treatment 1.3 Aftermath: hearing loss 1.4 Vaccination Unit 1 takes place on a college campus where we are trying to identify and contain an unknown pathogen that has broke out on campus. We will contract trace, use tools to ID the pathogen, and looks out potential treatments and guidelines for the campus. Unit 1 exam after completion of 1.4 1.1.3 PCR vs Cycle Sequencing (Sanger) Polymerase Chain Reaction Technique used to make millions-billions of a specific DNA sequence or sample All products of PCR will be the exact same length and sequence Many labs in genetics require PCR to be done first Cycle Sequencing Technique used with electrophoresis to determine specific DNA sequence Products of cycle sequencing will vary in length based on original sample. Uses DDNTPs and fluorescent dye to mark the presence of specific base  Meningitis Meningitis is a broad term that means inflammation within the protective membranes across the brain/spinal cord (meninges). Usually caused by infection- Viral, bacterial, fungal, etc.. Symptoms include: ○ Fatigue ○ Headache/confusion ○ Stiff neck ○ Vomitting ○ Fever Can be fatal if not treated quickly. What was the specific casue of our outbreak on campus? 1.1.4-1.1.6 ELISA & the immune system Immunoglobulin Created via B cells Used to identify and neutralize pathogens and harmful components Comprised of constant region (heavy chain) and variable region (light chain) ○ Constant is the region that denotes the antibody as self ○ Variable region is specific to an antigen Humans have 5 classes of antibodies ○ IgA-Mucus membranes, saliva, and tears ○ IgD-Activates other immune cells such as basophiles ○ IgE-allergic reactions ○ IgG-binds to antigen to flag for destruction, neonatal protection, most common Ig ○ IgM-first to fight 1.1.4-1.1.6 ELISA & the immune system ELISA- Enzyme Linked Immunosorbent assay Uses antibodies to detect the presence of a target and produce a color change. Can be designed to test for antigen, antibody, or hormone/protein Typical pregnancy test- test for HcG Amount of color change can give us qualitative measurements of concentration Steps ○ Patient sample/target ○ Primary Ig ○ Secondary Ig with enzyme ○ Substrate- positive test will produce color change 1.2 Bacteria & Antibiotics Bacterium Basics Common shapes: Cocci- Spherical structures Bacillus- Rod like in structure Spirilla- Spiral structure Vibrio- Comma shaped structure Many others Gram staining 1884 Differentiates bacteria into Positive (+) or Negative (-) based on specific properties and structure of their cell wall. Gram Staining is almost ALWAYS the first step when needing to ID a specific bacteria Mixed gram stain ( + and -) of some unknown bacillus strains. Gram positive bacteria One cell membrane Thick layer of Peptidoglycan ○ Very porous so molecules can pass through Capsule (not noted in diagram) Typically easier to treat with antibiotics Common examples: Staphylococcus aureus, Streptococcus pneumoniae, Mycobacterium tuberculosis Gram Negative Bacteria Inner membrane Thin layer of peptidoglycan outer layer membrane ○ Contains LPS (Lipopolysaccharide) ○ O antigen—>potential septic shock Capsule (not noted) Second outer membrane can make it more difficult to treat Examples: E. Coli, Chlamydia trachomatis Lipopolysaccharides (LPS) Often dubbed ‘endotoxin’ 3 main components ○ O antigen ○ Core ○ Lipid A (toxic) Endotoxin v. Exotoxin ○ Endo- Held within or on the bacterium & typically only released upon cell death ○ Exo- released by the bacteria into environment or another cell Deeper research had found the LPS can be released without cell death. A deeper dive can be found here on lipopolysaccharides.  Positive vs. Negative Gram Positive (+) Gram Negative (-) Single membrane 2 membranes ( inner & outer) Thick layer peptidoglycan (cell wall) Outer membrane contains LPS Capsule Relatively thin layer of peptidoglycan Will stain Violet/ purple (cell wall) Lack of second membrane makes + Capsule more susceptible to antibiotics Will stain pink/redish Outer membrane makes them more difficult to target with basic antibiotics What stain do you believe meningitidis to be? Antibiotics Antibiotic - “opposing life” in ancient greek A type of antimicrobial substance that targets bacteria Ineffective against Virus bodies 4 types we will cover in class ○ Beta lactams ○ Tetracyclines ○ Fluoroquinolones ○ Sulfa drugs (Sulfonamids) ß-Lactams Signature Beta-lactam ring Most commonly prescribed antibiotic class Inhibits cell wall synthesis ○ Beta-lactam ring inhibits transpeptidase ○ Low cell well integrity ○ Lysing of cell Common examples: Penicillin & derivatives, cephalosporins, cephamycins Tetracyclines “Cyclines” Disrupts growth and proliferation of bacteria ○ Inhibits 30S subunit thus block tRNA ○ No proteins= No life Effective against both Gram positive and negative bacteria that are aerobic ○ Limited effect on anaerobic bacteria Examples: Doxycycline, minocycline Fluoroquinolones Fluorine atom present at 6’ position Acts be disrupting DNA replication ○ Inhibits DNA gyrase (Topoisomerase II) or Topoisomerase IV ○ Replication stalls and no new bacterium can be created Note; this class does not typically kill existing bacteria, but prevent the growth and spread of bacterial populations Examples: Ciprofloxacin, very common  Sulfonamids Acts on both gram negative and positive Does not kill but rather inhibits multiplication and proliferation Inhibits folate synthesis ○ Folic acid is a precursor to nucleotides (A,T,G,C) ○ Most drugs inhibit an enzyme called DHPS or PABA Examples: Sulfadiazine & Sulfamethizole Some history for ya.. Alexander Fleming Discovered penicillin via mold within the lab Mary Hunt Discovered different species of fungi that produced 200x more penicillin Antibiotic resistance When an bacterium becomes unresponsive to a specific antibiotic. Three main types: ○ Mutation- a change in DNA sequence= change in target Remember- bacteria can go through many generations within the same day ○ Inactivation- Codes a protein that will inactivate the incoming antibiotic. Destruction/inactivation of antibiotic via protein Gene is found on plasmid ○ Efflux- Channel that exports antibiotics out of cell Active transport Pump- creates concentration gradient to allow antibiotic to flow out of cell. Modes of genetic transmission Bacteria can share their plasmids in multiple ways that allow the spread of antibiotic resistant genes among new populations. This spread of resistance is a major focus in modern medicine. ○ Conjugation- Physical touch via pilus ○ Transduction- Bacteriophage is transmitting resistant genes among different populations of bacteria. ○ Transformation - Plasmid is emitted into the environment by bacteria and then can be endocytosed by different strains of bacteria. 1.3 Hearing loss  1.3.1 & 1.3.2 You must know the anatomy of the ear. You will be tested over this on the unit 1 exam and EOC You must know the propagation of sound through the ear (what order the structures work) Conductive hearing loss- Think of this as a mechanical failure. Something in the middle or outer ear is not passing vibrations properly. ○ Usually middle ear Sensorineural hearing loss- As the name suggests, this is an issue within the innear. ○ Could be auditory nerve ○ Could be cochlear stimulation ○ 99% the issue is within the inner ear or auditory nerve/other nervous issue  No hearing loss Audiograms A graphical representation of how well you hear specific pitches and tones Measures both ears individually, usually denoted by red/blue lines) Moderate hearing loss in both ears Can detect both sensorineural and conductive hearing loss I've seen these on the EOC the last two years so you will need to be able to read and diagnose a pateint.  Conductive hearing loss Audiograms continued The lines are representative of your air conduction (sensorineural) and the brackets are representative of bone conduction (conductive) Good hearing When the brackets or bone conduction is 10+ decibels higher than air conduction, the patient has conductive hearing loss. Audiologist would analyze the lines within the graph (slope) to determine what pitches and volumes the patient struggles to hear. Summary.. Simplifying it.. You are looking to see how far down the lines go on the Y axis and then compare that to what frequency it corresponds to on the X axis. Take the top right audiogram for example. Both the left and right ear show Moderate (41-55) hearing loss at all frequencies. Thus, we would diagnose the patient with Moderate sensorineural hearing loss in both ears. 1.4 Vaccinations  Vaccine Chart type Description example Live-attenuated vaccines use disease-causing viruses that Vaccines for MMR, Varicella, have been grown in a series of Rotavirus, Shingles, and Yellow cell cultures or embryos This Fever causes the virus to be unable to replicate in humans effectively. Inactivated or Killed vaccines created by inactivating the Vaccines for Polio, Hepatitis A, pathogen, usually using heat or and the yearly influenza vaccine chemicals. This destroys the pathogen’s ability to replicate, but keeps the pathogen intact. Toxoid vaccines created by inactivating the toxin Vaccines for Tetanus, Diphtheria, that a bacteria releases using and Rabies heat or chemicals. The inactivated toxoid is then placed in the human body to elicit an Chart continued type Description Example Subunit vaccines Subunit vaccines use only Vaccines for Hepatitis B, pieces of the pathogen. Pertussis, Meningococcus, One example of a subunit Pneumococcus, Influenza, vaccine is a specific and Haemophilus protein from the pathogen influenza type b (Hib) that can elicit a human immune response. Conjugate vaccines Conjugate vaccines use Vaccine for HPV pieces from the coats of bacteria along with a carrier protein. The two combined elicit an immune response from the human body when  Bacterial plasmids DNA found typically in circular structures and are separated from genome. These plasmids do not contain genes necessary for life but rather quality of life updates They replicate independently of the chromosomal DNA Plasmids can be transmitted in a few different ways allowing bacteria to spread helpful genes to one another (antibiotic resistance) ○ Conjugation- contact ○ Transformation-naked DNA in environment ○ Transduction - bacteriophage  Exam 1 details October 16th and 17th (wednesday and thursday) (questions/structure) Summative 100 point exam You have the entire class period to complete the exam ○ Time 1.5 will stay to finish the exam and sent w/ a note See reassessment policy posted on canvas if you wish to retake If you are absent-send me and email-come see me- YOU need communicate with me to schedule a make up exam.