CA1 TYS Learning Points Flashcards
Metagenomic analysis of oral flora involves:
Next generation high throughput sequencing of DNA
Large droplets travel within the distance of
1m
How is chicken pox spread?
- airborne (respiratory droplets)
- direct contact w lesions, saliva, blisters, mucus
- appears in 10-21 days of infection (aka length that u need to monitor aft exposure)
Gram +ve bacteria appear gram -ve after awhile if..
Too much ethanol is applied (eventually, decolourisation of thick peptidoglycan layer, cuz usually they retain the purple stain aka. Gram complex)
Which hepatitis virus is an RNA virus, not common in general pop, but common in needle users and haemodialysis patients & causes liver disease.
Hep C
- transmitted by infected blood & sex
- usually found in developing countries
- asymptomatic
- no vaccine
- persistent & chronic
What is the most associated lesion in early HIV
Cervical lymphadenopathy (Abnormal enlargement of lymph nodes in head and neck)
(Acute HIV infection = fever, rash)
- HIV blood count highest at the start (acute infection)
Nurse gets contact w px w chicken pox, no VZV vaccine, must monitor for how long?
10-21 days (thats how long it takes to see first signs of chicken pox
Blood spill, what agent to clean up? (Fast acting on virus)
Hypochlorite (Bleach)
What are the most contagious antigens of hep B?
- HepB surface antigens (HBsAg)
- HepB E antigens (HBeAg)
- i think the HBV DNA & HBcAg is also highly infective and contagious
First colonisers after tooth eruption are?
Streptococci
After baby is born, which organism dominates first?
Streptococci
Selective IgA deficiency leads to..
Sinusitis (inflammation of sinus lining
Bronchiolitis in infants is likely to be caused by
RSV (respiratory syncytial virus)
How long does it take for acute infection of fever and rash to show aft HIV infection?
1-6 weeks
You are most likely to get HIV
- blood contact!!
- bitten w blood in saliva > needle stick injury
Most likely to get hepatitis when..
U r an injecting drug user> sex or needle stick injury
Bee sting resulting in swollen face, severe hypotension. Mediated by which antigen?
IgE. (Hypersensitivity)
Mouth palatal vesicle lesions w that specific picture.. (pic shows red dots on palate)
Coxsackie (HFMD)
Analysis of microbial flora in oral cavity, what is the best to analyse?
16s ribosomal RNA
We have live attenuated vaccines for..
- Measles (paramyxovirus)
- Influenza (change in HA & N to match seasonal change)
- VZV (chicken pox)
A boy gets fever, rash, diagnosed w chicken pox. Which antibody association?
IgM (cuz primary infection)
New generations of vaccines must include what in order for an effective influenza vaccine?
Envelope glycoproteins.
Two glycoproteins on the surface of influenza virus, hemagglutinin and neuraminidase, play a prominent role in the process of influenza virus infection and release.
- HA & N
- is the thing that changes with the strain!
Fever, increased gram -ve bacteremia and increased eosinophilila, test for what?
Gut parasite
Parasitic infection involves:
- mast cells, basophils, eosinophils
Intra epithelial lymphocyte is primarily
CD8 T cell (cytotoxic)
Intra-epithelial lymphocytes: lymphocytes found in the epithelial layer of mucosa
Womans nose is blocked, cannot breathe, unexplained breathing. Doctor does a biopsy bcuz he suspects which virus?
EBV (prolly cuz nasopharyngeal carcinoma)
Pathogen causing opportunistic infections come most commonly from which reservoir
Patient’s own commensal flora
What part of bacteria prevents attachment to surface by immune cells, and is a major virulence factor?
Polysaccharide capsule
- protects bacteria from phagocytosis
- prevent Ab entry
- prevent immune cell attachment
Virus injected into B cells causes immortality. What virus is this?
EBV
What can be spread ard by aerosols?
Chicken pox
(Not influenza! I think chickenpox spreads better than influenza airborne thats why.. influenza is through large droplets)
A child had dengue 3 days ago, which immunoglobulin will be high?
IgM
Which cell type is cytotoxic and is a part of innate immunity/wo need for adaptive immunity response?
NK cells
- induces apoptosis of virus-infected & tumour cells
What size shd the membrane pores of the filter be to remove bacteria without removing virus?
0.4 microns
Successful HIV treatment due to improvements in HAART leads to increase in incidence of what syndrome?
Oral warts
HAART (highly active anti-retroviral therapy) (suppresses HIV viral replication)
- increases incidence of oral papilloma (warts)
- decreases incidence of hairy leukoplakia & kaposi sarcoma
Experimental vaccine against which bacteria can prevent caries?
S. Mutans/Streptococcus Mutans
Relatively clean surface, kills viruses fast:
Iodine povidone
Creutz Jakob disease causes neurological degeneration. What is this pathogen made up of?
Prions (proteins)
Bowie dick tape test, what does it test for?
Sufficient steam gravity
- ensure air properly removed => ensure steam penetration
- is the zebra patterned tape
MALDI-TOF detects what?
Protein and peptides (purpose is to identify bacteria)
- issa mass spectrometry method to test for molecular markers
Bacterial resistance genes can be transferred to another bacteria via conjugation. This is a property of what?
Plasmids
Tongue papillae has low redox potential, what organism’s growth is supported in this environment?
Anaerobes
Low redox potential: more anaerobic and reduced conditions
Relatively clean surface can use what type of disinfectant to clean, and can achieve fast antiviral action?
Povidone iodine
Intravenous fluid contaminated by which substance found in bacterial cells can result in signs and symptoms of septic shock, even if no viable bacteria are found?
Lipopolysaccharide
- endotoxin that is present only in gram -ve cell walls
Removal of which organ causes increased risk of infection by encapsulated bacteria like Strep pneumoniae?
Spleen
Vaccinate against what virus can reduce risk of cancer?
HPV
Virus that causes jaundice, and is transmitted mainly by contaminated food and water and unhygienic environment.
Hep A
One of the COVID extrapulmonary symptoms is..
Loss of smell
Extrapulmonary means outside of lungs
Healthy patient gets severe pneumonia, what virus likely caused it?
Adenovirus
Patient with fever and cough for 3 days being tested for covid-19. Which lab test would be the best and most accurate?
Nasopharyngeal swab with PCR
N95 is needed to protect healthcare professionals against contagious respiratory illness spread by aerosol. Why is it called N95?
Prevents 95% of particles of 0.3 microns
Hep B vaccine causes the body to have pre-formed antibodies. What do these antibodies do when the person gets the virus later in life, which helps to prevent the disease?
Prevents virus from binding to receptor
HIV gp120 glycoprotein binds to which receptor on host?
CD4 receptor (helper T cells)
Which virus is of a different structure in terms of genetic material and structure?
A. Hep B
B. Enterovirus
C. Hep A
D. Polio
E. Coxsackie A
A. Hep B (is DNA)
B. Enterovirus
C. Hep A
D. Polio
E. Coxsackie A
- the rest are ssRNA
Influenza virus requires yearly vaccination bcuz of..
Antigenic drift
- seasonal change of antigenicity
- accumulation of a series of minor RNA genetic mutations (change in HA & N) (is the same virus)
HIV: how long can a patient last until opportunistic infections first start to appear, assuming no treatment was undertaken?
1-10yrs
Which structure does gram -ve bacteria have more than gram +ve bacteria?
LPS (lipopolysaccharide)
What virus most commonly causes post-transplant organ rejection and fatal pneumonia
CMV
Virus that causes HFMD?
Enterovirus, coxsackie
Cytotoxic T cells release what to kill?
Perforin & granzyme
Which of the following presents antigens to immune cells of the body?
Dendritic cells
Which bacteria in the oral cavity is responsible for the most cariogenic exopolysaccharide layer?
Strep mutans
What viruses are truly airborne?
- chicken pox
- measles, mumps
- mycobacteria TB
(All spread thru respiratory droplet nuclei, influenza only spread via large droplets)
When a person sneezes, most of the large respiratory droplets settle how far away?
1m
A child suffers a fever and has vesicles at the back of the throat. Which virus is the most likely?
Enterovirus
What are the steps in a gram -ve staining?
- Crystal violet
- Lugol iodine
- Decolourise
- Safranin counterstain
Packaged goods can be sterilised by..
Steam penetration
- test using bowie dick tape test
Gram-negative sepsis leading to end-organ failure occurs due to:
Increased vascular permeability (& excessive blood vessel dilation)
- cuz of LPS, which can still cause septic shock even when bacteria is dead
- end-organ failure, death
How do we test/sample whether polio is still ard in the environment?
Test sewage.
Which of the antibodies is formed as pentamer?
IgM
