micro 201 Flashcards
Give an example of external defenses that are non-specific.
i. Mucus
ii. Cilia lining respiratory tract
iii. Acid in stomach
Give an example of Internal defense in the body.
i. Phagocytosis
ii. Complement system
iii. Interferon system
Innate vs Adaptive
INNATE IMMUNITY
is One non-specific
Two early defenses
Three physical barriers, microbial factors, phagocytic cells
ADAPTIVE IMMUNITY
are B & T cells
Antigen-specific
Later defenses
Results from the activation of one or more classes of
lymphocytes
How do Phagocytosis Work?
Neutrophils recognize surface proteins on the cell walls of bacteria adheres to them then the folds its membrane around the bacteria then releases digestive enzymes to kill and digest bacteria.
How does the complement system work?
The first complement will recognize the bacteria and attach to it, which then will activate the other complement components causing a castigate effect of activation of the complement system until the bacteria is completely coated in complements which will make it easier for macrophages, neutrophils and other pathogens to phagocytosis the bacteria.
How does the Interferon system work?
When a cell is infected, it will release interferon proteins to signal to uninfected cells to stay away and will induce changes in the uninfected cells that help them become temporarily resistant to the infection, the release of the Interferon protein will also activate natural killer cells that will help kill off the virus and the infected cells that are releasing the interferon proteins.
B-cells VS T-cells (4 points each)
B lymphocytes
1. works on foreign antigen before it enters a cell
2. Involve antibodies
3.helps gainst extracellular viruses and bacteria, toxins
4. Binds to antigens in body fluids
T lymphocytes
1. works on foreign antigen after it has entered a cell
2. No antibodies involved
3. hepl against virus-infected cells, tumor cells, transplanted organs
4. Can only bind to antigen epitopes which are presented to them on the surface of cells
How do B cells work
The B cell has two immune responses, primary and secondary. Primary only occurs, If the foreign body has never been detected before, The B-cell will attach to the virus and becomes a memory B cell. The secondary Immune response occurs when the body has previously encountered the foreign antigens and is able to respond rapidly by creating more of the memory B cells from its last encounter with the antigen.
How do T cells work?
There are two main types of T cells, cytotoxic T cells and helper T cells. T-cells have receptors covering their surface which are antigens specific, which means they can only bind to one shape of antigen, when helper T-cells bind to viral antigens and send out signals to the cytotoxic T cell who releases cytokines to help kill the infected cells.
Endogenous Vs Exogenous
Endogenous: Comes from inside the body, e.g., appendicitis.
Exogenous: Come from outside, e.g., C Difficile.
Definition of Streptococcus pyogenes (S.pyeogenes)
An autoimmune
disease affecting
the heart, joints, skin and brain.
name 2 disease streptococcus pyogenes can make.
- Rheumatic heart disease
- Rheumatic fever
name 2 disease Streptococcus pyogenes can
make
- Rheumatic heart disease
- Rheumatic fever
Pathophysiology of Streptococcus pyogenes in Rheumatic fever (3 steps)
- Stars as a untreated recurrent infections of S. pyogenes leading to.
- Repeated attacks of rheumatic fever.
- Then goes to rheumatic heart disease which is long-term damage from rheumatic fever.
Autoimmune mechanism of the body against Streptococcus pyogenes.
Streptococcal A phosgene’s are recognizes by the Immune system by the M protein on the surface of the compound. Because this compound is so similar to host proteins antibodies found on cardaic tissue and may mistakenly identify the host as the foreign pathogen and attack the host as well
Signs & Symptoms of Streptococcus pyogenes
- Fever
- Swollen joints
(pain) - Rash
Diagnostic Test for Rheumatic fever (5)
- Inflamed heart muscle (T-cells directed against heart muscle proteins)
- Erythema marginatum – rash
- Random, involuntary body movements
- Throat swab + bacteria culture.
- if disease happened 3-4
weeks after infection, bacteria may not be present in throa
Management of Streptococcus pyogenes (4)
1.Give aspirin, NSAID
- Oral penicillin for 10 days
- Prevent recurrence
Amoxicillin (PO),
4.Benzathine penicillin
(IM) for years or until they reach about 20yo
Definition of staphyloccocus aureus
An inflammation and or infection of the of tissue
name 2 disease S.aurses
Tonsilitis, and pharyngitis.
Pathophysiology of staphyloccocus aureus in pharyngitis (3)
- The bacteria adhere to the pharyngeal mucosa.
- It then invades the mucosal tissue by producing various proteases and cytolysins
- Causing inflammation manifesting as signs and symptoms of pharyngitis
autoimmune mechanism of the body against staphyloccocus aureus
Toxins from the S. aureus trigger inflammatory responses and activate inflammatory cells, such as keratinocytes, helper T cells, innate lymphoid cells, macrophages, dendritic cells, mast cells and, neutrophils.
Signs & Symptoms (5) staphyloccocus aureus.
- Redness
- Swelling
- Heat
- Pain
- Loss of function in that area
Diagnostic Test for staphyloccocus aureus.
Swap of puss or infection.
Throat swabs.
Management of staphyloccocus aureus.
A cours of antibiotics, Penicillin, or amoxicillin.
Signs & Symptoms Helicobacter pylori (4)
- Excessive diarrhea may be blood stained.
- fever
- An ache or burning pain in your stomach.
- Unintentional weight loss
How to say Helicobacter pylori
(hell-o-co-back-ta-er pie-law-i)
Definition of helicobacter pylori
an infection that occurs within the upper GI tract
that may cause ulcers, and information.
Pathophysiology of helicobacter pylori
H. pylori gastritis typically starts as an acute gastritis in the antrum, causing intense inflammation and, over time, it may extend to involve the entire gastric mucosa, resulting in chronic gastritis.
name 2 disease helicobacter pylori can make.
- Peptic ulcer disease
- Chronic gastritis
immune mechanism of H. Pylori
immune mechanism:
H. Pylori cause a strong systemic immune response,
Creating a chronically inflamed environment with reduced stomach acidity that favors the growth of other bacteria in the GI environment,
maintaining the inflammation and thereby reducing the level of vitamin C in the gastric juice
Signs & Symptoms helicobacter pylori
- Excessive diarrhea may be blood stained.
- fever
- An ache or burning pain in your stomach.
- Unintentional weight loss
What are diagnostic test for helicobacter pylori
- Gram-negative
- A tissue biopsy of stomach lining
- A blood test of antibodies
Management of H. pylori (2)
- H. pylori infections are usually treated with at least two different antibiotics at once to helps prevent the bacteria from developing a resistance.
- Proton pump inhibitors (PPIs) to help heal the gut
How to day escherichia coli
(S -ska-ric-e -a)
Definition of escherichia coli
An bacteria in the gut that can star to harm the host if they feel they can or need to.
how does a appendicitis start
Buildup of bacteria, In the appendix, Due to obstruction or blockage
Give two examples of escherichia coli in the body.
- Appendix
2.UTI
Which age group has the highest rates of pneumonial disease?
over 65 years old
Which bacterial species is the most common cause of pneumonia in people living in New Zealand?
Streptococcus pneumoniae
Which antimicrobial is most likely to kill the bacterial species that is the most common cause of pneumonia in people in New Zealand?
penicillin
Which immune cell is the first to challenge S. pneumoniae upon migration to the alveolus?
macrophage
A positive Ziehl-Neelsen stain indicates
an acid fast bacillus
When educating women about prevention of a UTI, what is one simple way the client can do this?
Wipe from front to back after passing urine
Which immune cell is responsible for clearing HBV infections?
cytotoxic lymphocyte
Which laboratory results indicate that the body fluids of the tested person have a high risk of transmitting hepatitis B virus?
serum is strongly positive for e antigen of hepatitis B virus
When caring for a client with hepatitis B, the nurse should monitor closely for the development of associated with a worsening decrease in hepatic function?
Irritability and drowsiness
While beta-lactam antibiotics remain one of the most commonly prescribed types of antibiotics, they have side effects that can range from mild to life-threatening in nature. What type of side effect is most commonly observed?
allergic reaction
Most strains of Staphylococcus aureus are resistant to penicillin because they are able to
produce an enzyme to destroy the drug
which antibiotic is a semi-synthetic antibiotic?
amoxycillin
Fluoroquinolone antibiotics inhibit the synthesis of
DNA
Which of the following antibiotics belong to the class of beta-lactams
penicillin
If treated, the time between HIV infection and AIDS disease is commonly
longer than 10 years
Where was HIV infection first transmitted from person to person?
Central Africa
The risk of HIV transmission is greatest for
an infected mother giving birth
Vaccination against a viral pathogen, e.g. influenza virus, results in the production of antibodies that help the body control the infection by?
blocking infection of new cells
Which of the following human vaccines should not be given to immunocompromised patients
Live vaccines e.g., Measles vaccine
The HiB (Haemophilus influenzae type B) vaccine is a component antigen vaccine given in New Zealand as:
4 immunisations between 6 weeks and 15 months old
Which microbial component most strongly inhibits phagocytosis and thereby greatly enhances the virulence of the bacterium that most commonly causes pneumonia in people in New Zealand?
capsular polysaccharide
Which of the following test results most strongly suggests that a person is at high risk of transmitting Mycobacterium tuberculosis to their close contacts?
profuse acid fast bacilli seen in sputum
The effective treatment of tuberculosis requires
a long course of multiple anti-mycobacterial antibiotics
what features does not protect against cystitis developing
high glucose load in urine
What is present in the vaccine used to protect against hepatitis B virus infection?
Purified hepatitis B virus surface antigen (HBsAg)
What is present in the vaccine used to protect against hepatitis B virus infection?
Purified hepatitis B virus surface antigen (HBsAg)
What is the usual method of diagnosing that a person has HIV infection?
Detecting antibody to the virus in the person’s blood
Herd immunity occurs when a large percentage of a population has become immune to an infection, thereby providing a measure of protection for individuals who are not, this is an example of
indirect protection
