Lyme Disease Flashcards
(45 cards)
What is the mode of transmission for Lyme disease?
Bite from an infected tick, introducing Borrelia into the bloodstream.
What type of organism is Borrelia and how does it behave in the body?
A motile bacterium that spreads through tissues, often causing a ring-shaped rash.
Suggest two reasons why is may take many weeks to show symptoms?
- Borrelia is a slow growing bacterium thus bacterium spreads slowly around the body.
- Immune system takes time to recognise pathogens.
Why is Gram staining not reliable for detecting Borrelia?
It does not stain well due to its unique cell wall, making Gram staining ineffective.
Why does Lyme disease cause tiredness?
It may cause mitochondrial dysfunction, reducing ATP production and energy.
How does Lyme disease affect the integumentary system (skin)?
Causes inflammation and redness; rash spreads as Borrelia moves through skin layers.
What is the immune system’s response at the bite site? (Natural barrier to reduce infection)
- Inflammation to localise break in skin
- The skin blood clotting to seal wounds
- Phagocytosis to destroy, phagocytes engulf and destroy pathogens.
Explain the humoral response? (Used to control and resolve infection)
(B cells) - When antigen binds to its specific receptor, the receptor activates and the B cell is stimulated to divide into Plasma and memory cells.
(Plasma cell) - These secrete antibodies -Then an antigen - antibody complex renders the antigen inactive which increases the rate of engulfment by phagocytes.
(Memory cell) - These divide into plasma and remain in circulation ready to divide if they if same antigen is encountered.
Explain the Cell-mediated immune response?
- Detection of the returned antigen causes production of T cell (lymphocytes).
- T cells cause lysis of target cells.
- Helper T cells cooperate and release cytokines.
- Memory T cells remain dormant for possible re-exposure.
4 steps of Innate (Initial) response for tick bite?
- Histamine released, signaling a response
- This causes vasodilation in which capillaries dilate clotting blood.
- Chemical signals attract phagocytes
- Phagocytosis
What are the main purposes of immune system?
Destroy;
- Pathogens
- Abnormal cell multiplication (cancer)
- Toxins
What is an antigen?
A molecule, often protein that is foreign to the body and stimulates an immune response. (Borrelia)
Structures within the skin (8)
- Hair
- Hair follicle
- Sweat gland
- Sweat pore
- Sweat duct
- Erector muscle
- Sebaceous gland
- Capillaries
Functions of key labelled parts of a synovial joint (6)
Synovial membrane – Produces synovial fluid which lubricates the joint and reduces friction.
Synovial fluid – Acts as a lubricant and shock absorber, allowing smooth movement.
Articular cartilage – Covers the ends of bones, reducing friction and absorbing shock.
Joint (articular) capsule – A tough outer layer that encloses and stabilises the joint.
Ligaments – Connect bone to bone and provide joint stability by limiting excessive movement.
Tendons – Attach muscles to bones and help control joint movement.
What are the 4 parts of an antibody that may be asked to label?
- Antigen binding sites
- Disulfide bonds
- Light chain (L)
- Heavy chain (H)
What is bioavailability?
The proportion of a drug that enters the circulation when introduced into the body and able to have effect
Purpose of ELISA test?
Technique using antibodies and colour change to identify a concentration of an antigen in a mixture.
Method of an ELISA test (1-7)
- Add Antigen – Antigens from the sample are attached to a multi-well plate.
- Incubate – Allow time for the antigens to adhere to the plate.
- Block Unbound Sites – Add a blocking solution (e.g. powdered milk) to prevent nonspecific binding.
- Add Specific Antibody – Apply a specific antibody linked to an enzyme, which binds to the antigen.
- Add Substrate – Add a solution containing the enzyme’s substrate.
- Observe Colour Change – The enzyme reacts with the substrate to produce a colour change.
- Measure Results – The intensity of the colour is measured using a spectrometer; a stronger colour indicates a higher antibody concentration.
What is an antibody and its structure?
A protein produced by the immune system to recognize and neutralize foreign substances.
A four polypeptide chain protein mimicking the shape of Y. (Tertiary & Quaternary)
How is the musculoskeletal system affected?
Muscle pain, joint pain, and later joint swelling due to inflammation in synovial joints.
How can Lyme disease impact the nervous system?
It may cause facial palsy, cognitive issues, or inflammation of nerves.
What aspect of nerve physiology is relevant in Lyme disease?
Transmission of nerve impulses along axons by charge distribution (neurophysiology).
Explain myogenic nature of cardiac muscle, transfer of electrical impulses through heart during heartbeat and how its controlled and coordinated. (Sytole x2 & Diastole)
- Cells conduct electrical excitation wave through heart.
- Electrical activity causes contraction of the atria then the ventricles.
- Excitation wave spreads through walls of atria.
- Atria contract.
- Excitation wave reaches atrio-ventricular node (AVN).
- Ventricles contract after brief 90ms delay
- Relaxation of both atria and ventricles follow
How does Lyme disease affect the cardiovascular system?
It can cause heart block (AV block), disrupting electrical conduction in the heart.
