PLTW - Medical Interventions Final Exam Study Guide

What is a medical intervention?

Any measure whose purpose is to improve health or alter the course of a disease

What are the main categories of interventions that function to maintain human health?

Treatments, Diagnostics and Equipment

How do scientists gather evidence during the potential outbreak of an infectious disease?

1. Record patient's symptoms and find similarities with other patients
2. Isolate the bacteria in a lab
3. Go to affected areas and determine the origin of the disease
4. Identify the disease using DNA sequencing since pathogens alter certain DNA sequences

What is bioinformatics?

The collection, classification, storage, and analysis of biochemical and biological information using computers. (Especially applied in molecular genetics and genomics)

How can DNA sequences be used to identify disease pathogens?

You can observe mutations and abnormalities that disease pathogens have

What is an antibody?

A blood protein in the body produced by B-cells (B-Lymphocytes) that fight against a foreign substance by recognizing a specific part of it.

How do antibodies identify and inactivate antigens?

1. Shape recognition
2. Proteins of the antigens are configured to specific antibodies, so the foreign antigens bind to the specific antibodies that inactivate them

How can the ELISA assay be used to detect disease?

1. Primary antibodies attach to specific antigen
2. Secondary antibody attaches to primary antibody
3. When enzyme substrate is added, color change occurs

Why is it important for doctors to know the concentration of the disease antigen present in a patient's system?

Higher concentration = closer to patient zero

Patient Zero

The first person to be infected with a particular disease

What steps do scientists take to diagnose, treat, and prevent future spread of a disease outbreak?

1. Record the symptoms
2. Locate the origin of the pathogen
3. Run tests to determine antibodies and antigens
4. Take preventative measures (quarantine, wash hands often, etc.)

How were the following used in managing the outbreak on Sue Smith's campus:
PCR, Bioinformatics/BLAST, and ELISA?

These tests determine the concentration of the disease, which lead to the source of the outbreak

Which part of the bacterial cell allows the bacteria to attach to specific surfaces?

Adhesins, or cell-surface components/appendages of the bacteria that facilitate attachment to other cells or surfaces

Which bacterial structure is involved with protein synthesis?

rRNA, tRNA, and mRNA (Ribosomal, Transfer, Messenger)

What is an endotoxin?

A toxin that is inherently present inside a bacterial cell

What is the structural difference between Gram positive and Gram negative bacteria?

Gram positive:
•Purple
•Thick cell wall
Gram negative:
•Pink
•Thin cell wall

How do antibiotics work to fight bacteria?

•Inhibit the cell wall
•Stop bacteria from reproducing/sharing resistant DNA

Penicillin

An antibiotic that penetrates and destroys the cell wall of gram negative bacteria

Tetracycline

An antibiotic that inhibits protein synthesis (reproduction) of mostly gram positive, but some gram negative bacteria

Fluoroquinolones

An antibiotic that inhibits the DNA gyrase of gram negative bacteria

Sulfa Antibiotics

An antibiotic that inhibits folic acid synthesis and growth of gram positive and negative bacteria

Folic Acid

Vitamin that helps the organism produce and maintain healthy cells

Efflux

Transport of a solute molecule from the inside to the outside of a cell

Destruction/Inactivation

Exchange enzymes that chemically degrade the antibiotic (How some bacteria develop resistance to antibiotics)

Mutation

A change in a gene or chromosome.

Explain the difference between limited spectrum and broad spectrum antibiotics.

Limited spectrum: only kills the cells that are infected.
Broad spectrum: kills all cells, even healthy cells.

What methods do bacteria use to share antibiotic resistant genes? Explain the difference between conjugation, transformation, and transduction.

Conjugation - The one-way transfer of DNA between bacteria in cellular contact.

Transformation -The genetic modification of a bacterium by incorporation of free-floating DNA from another ruptured bacterial cell.

Transduction - The transfer of genetic material from one organism (such as bacteria) to another by a genetic vector.

What is the difference between the chromosomal DNA and plasmid DNA when thinking about antibiotic resistance?

Bacteria possess a single chromosome composed of double‐stranded DNA in a loop. The genetic information of the plasmid is usually not essential to survival of the host bacteria. Plasmids can be removed from the host cell and the bacteria can still survive.

What is the best antibiotic to use when treating a Gram-positive bacterial disease?

Flouroquinolones or Tetracyclines

How would you determine which strain of Streptococcus aureus had a plasmid for resistance to streptomycin?

Performing a Disc Diffusion test

What actions are humans taking that are contributing to bacteria becoming resistance to commonly used antibiotics?

1. Preserving the potency of antibiotics
2. Taking the full dosage of antibiotics without missing one

What are the health impacts if you do not take your complete course of antibiotics that have been prescribed for your illness?

The disease will come back, and for an even longer period of time

Why are antibiotics ineffective against viral diseases?

Antibiotics are designed for bacteria, not viruses

How do frequency and amplitude affect how humans interpret sound?

F - pitch/tone
A - loudness/volume

What causes different types of hearing loss?

1. Sensorineural - Hearing loss or impairment resulting from problems with the auditory nerves

2. Conductive - Hearing loss or impairment resulting from interference or blockage of the transmission of sound waves to the cochlea.

How is hearing loss diagnosed?

Performing an Audiogram

Describe the difference between sensorineural hearing loss and conductive hearing loss.

Cochlear vs. auditory nerves

If you listen to very loud music, non-treatable hearing loss may result. The damage involves what structure of the ear?

Cochlea hairs

What part of the ear converts stimuli from the outside environment into nerve impulses for transmission to the brain?

cochlea

What interventions are available for patients with hearing loss?

1. Cochlear Implant
2. Hearing aid

What are the bioethical concerns related to the use of cochlear implant technology?

1. Separating from the deaf community
2. Financial issues
3. Social life
4. Future life

Describe how a cochlear implant works.

Enables individuals with sensorineural hearing loss and to recognize some sounds. Receives and converts sound waves into electrical signals which are transmitted to one or more electrodes implanted in the cochlea

What is vaccination?

An antigen-specific stimulation of the host immune response to prevent infectious disease

How does a vaccine activate the body's immune system?

A slightly disabled sample of the bacteria is inside the vaccine which triggers the body's immune response to fight it back

How has vaccination impacted disease trends in our country?

1. It has eliminated diseases like polio and smallpox
2. Herd immunity

What is herd immunity?

Immunity in most of a population

What methods are used to produce vaccines in the laboratory?

•Live attenuated (weakened)
•Killed or inactivated
•Toxoid
•Genetically engineered

What is recombinant DNA technology?

Allows amplification and isolation of specific genes

What are the molecular tools used to assemble recombinant DNA?

scissors/restriction enzyme, glue/ligase

How can recombinant DNA and bacterial cells be used to produce vaccines?

The bacteria can express the gene that was placed into the plasmid to produce the necessary antigen for the vaccine

How can engineered plasmid be inserted into bacterial cells?

the recombinant plasmid is made and inserted into bacteria via transformation

What is epidemiology?

The study of the prevalence of disease

How can epidemiologists assist with the detection, prevention, and treatment of both chronic and infectious disease?

They can provide the quantitative evidence for justifying needed policies. Also, their input can be helpful in demonstrating the effectiveness of policies once they have been adopted

What is genetic testing?

Techniques used to detect genetic mutations or chromosomal abnormalities

What are the duties of a genetic counselor?

Make recommendations to the patient and their families after diagnosing genetic mutations or chromosomal abnormalities

What is the goal of PCR?

Used to amplify specific sections of DNA

What are the steps of the PCR process?

1. Denaturation - 98 degrees -- separating DNA

2. Annealing - 48 to 72 degrees -- allows primer to base pair complementary DNA template

3. Extension - 68 to 72 degrees -- extends prime to form nascent DNA strand

What is the relationship between phenotype and genotype?

P - Physical and physiological traits on an organism
G - The genetic makeup of an organism (Tt, tt, TT)

What are SNPs?

(Single nucleotide polymorphisms) One base-pair variation in the genome sequence

How can restriction enzymes and electrophoresis be used to identify SNPs and determine genotype?

Restriction enzymes cut the DNA at a specific sequence and gel electrophoresis separates the fragments by size. By looking at the control, you will be able to determine the genotype

What medical interventions and lifestyle modifications can help a pregnant woman have a healthy pregnancy?

1. Take Folic Acid vitamin
2. Avoid alcohol and drugs
3. Decrease stress

What can amniocentesis and chorionic villus sampling tell a couple about their developing fetus?

1. Genetic abnormalities
2. Congenital Defects

Antibody

An antigen-bonding immunoglobulin, produces by B cells, that functions as the effector in an immune response

Antigen

A foreign macromolecule that does not belong to the honest organism and elicits an immune response

Bioinformatics

The collection, classification, storage, and analysis of biochemical and biological information using computers especially as applied in molecular genetics and genomics.

Concentration

A measurement of how much solute exists within a certain volume of solvent

ELISA (enzyme-linked immunosorbent assay)

A quantitative in vitro test for an antibody or antigen in which the test material is absorbed on a surface and exposed either to a complex of an enzyme linked to an antibody specific for the antigen or an enzyme linked to an anti-immunoglobulin specific for the antibody followed by reaction of the enzyme with a substrate to yield a colored product corresponding to the concentration of the test.

What is an enzyme?

A substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction.

Genome

The complement of an organism's genes; an organism's genetic material

Outbreak

A sudden rise in the incidence of a disease

Pathogen

A specific causative agent of disease

What is a primer?

A short segment of DNA that acts as the starting point for a new strand

Serial Dilution

A stepwise dilution of a substance in solution.

Solute

A substance that is dissolved in a solution.

Solution

A homogeneous mixture of two or more substances, which may be solids, liquids, gases, or a combination of these.

Solvent

A liquid substance capable of dissolving other substances

Substrate

The reactant on which an enzyme works.

Antibiotic

A substance produced by or derived from a microorganism and able in dilute solution to inhibit or kill another microorganism.

Antibiotic Resistance

Resistance to one or more antibiotics, usually due to additional genetic information

Conjugation

The one-way transfer of DNA between bacteria in cellular contact.

Nucleoid

The DNA-containing area of a bacterial cell.

Plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome

Transduction

The transfer of genetic material from one organism (such as a bacterium) to another by a genetic vector.

Transformation

The genetic modification of a bacterium by incorporation of free DNA from another ruptured bacterial cell.

Audiogram

A graphic representation of the relation of vibration frequency and the minimum sound intensity for hearing.

Cochlear Implant

An electrical prosthetic device that enables individuals with sensorineural hearing loss to recognize some sounds and that consists of an external microphone and speech processor that receive and convert sound waves into electrical signals which are transmitted to one or now electrodes implanted in the cochlea where they stimulate the auditory nerve.

Conductive Hearing Loss

Hearing loss or impairment resulting from interference with the transmission of sound waves to the cochlea.

Hearing Aid

An electronic device for amplifying sound before it reaches the receptors organs.

Inner Ear

The essential part of the vertebrate organ of hearing and equilibrium that includes the vestibule, the semicircular canals, and the cochlea.

Middle Ear

The intermediate portion of the ear containing a chain of three ossicles that extends from the tympanic membrane to the oval window and transmits vibrations to the inner ear.

Outer Ear

The outer visible portion of the ear that collects and directs sound waves toward the tympanic membrane by way of a canal which extends inward through the temporal bone.

Sensorineural Hearing Loss

Hearing loss or impairment resulting from problems with the auditory nerves

What is sound?

A disturbance that travels through a medium as a longitudinal wave

Case-Control Study

A type of epidemiological study where a group of individuals with the disease, referred to as cases, are compared to individuals without the disease, referred to as controls.

Cohort Study

A type of epidemiological study where a groups of exposed individuals (who have been exposed to the potential risk factor) and a group of non-exposed individuals are followed over time to determine the incidence of disease

DNA ligase

A linking enzyme essentials for DNA replication and recombinant DNA techniques.

Epidemic

Affecting an atypically large number of individuals within a population, community, or region at the same time.

Epidemiology

A branch of medical science that deals with the incidence, distribution, and control of disease in a population.

Inoculation

The introduction of a pathogen or antigen into a living organism to stimulate the production of antibodies.

Plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome.