Second Year X Flashcards
1
Q
What is an agonist ?
A
2
Q
What is an antagonist?
A
3
Q
What is the difference between competitive and non competitive antagonists
A
4
Q
Give an example of a drug that is an antagonist
A
5
Q
What is non adherence
A
it is when a patient doesn’t take their medications / treatment for many reasons.
6
Q
What are the two main types of non adherence
A
intentional and non intentional
7
Q
Give reasons / examples for each type of non adherence
A
8
Q
How can a medical professional improve adherence to
A
9
Q
Name various ways of administering different medications
A
Oral
Sublingual
Rectal
Parental
Topical
10
Q
What are the two types of adherence
A
Intentional and non intentional
11
Q
What are the factors doctors need to consider when their choosing an administration route
A
If a healthcare professional would have to administer it .
If it would be broken down by the digestive system .
Any side effects due to the method .
How predictable the dosing /absorption is .
How fast the drug can take effect once administered.
How easy it is to do .
Patient preference .
Where the drug is needed
12
Q
How do doctors decide which is the best medication to prescribe .
A
Diagnosed correctly ?
Patient choice
Cost effectiveness
Other health concerns
Side effects
Benefits >risks
Patient history
Current medications
13
Q
How are drugs work on enzymes?
A
The drugs resemble the natural substrates, bind enzymes and cause change in their activity this can either take place by the activation or inhibition of enzymes.
14
Q
How do drugs affect transport across membranes ?
A
As cell membranes are selectively permeable and membrane permeability is key to drug absorption,distribution and elimination effectiveness .
15
Q
How can drugs affect hormones ?
A
Medicines are effected by the endocrine system by either : inhibiting , stimulating or interacting with hormone receptors and a big example is with fertility.
16
Q
How can drugs affect transmitter substances?
A
Drugs can affect the communication between synapses in the brain by disrupting neurotransmission either by acting by or reducing or enhancing synaptic transmission
17
Q
What is Polypharmacy?
A
It describes when a patient is taking more than one medication at the same time , and the effect they can have on each other .
18
Q
What are the three ways that polypharmacy can affect drug action ?
A
patient factors, disease‐related factors, and healthcare factors.
19
Q
What is synergistic polypharmacy ?
A
When two drugs work on the same body system - can be helpful or harmful .
20
Q
What is antagonistic polypharmacy?
A
When drugs work against each other or counteract each other .
21
Q
What are some common foods that interact with medicine ?
A
Grapefruit
Black liquorice
Alcohol
Milk
Yogurt
22
Q
Example of synergistic polypharmacy?
A
Ramipril with amlodipine . Ramipril is an ACE inhibitor and amlodipine is a vasodilator.
23
Q
Example of antagonistic polypharmacy?
A
Propranolol with salbutamol . Propranolol antagonises the receptor that salbutamol normally binds to .
24
Q
What does drug tolerance mean ?
A
It means when the body has become used to a specific drug and there is less receptors being produced to bind to the medication.
25
What are the two mechanisms for developing drug tolerance ?
1. Decreased binding affinity between a drug and receptor .
2. Decrease in the number of receptors
26
What are the two mechanisms for developing drug tolerance ?
1. Decreased binding affinity between a drug and receptor .
2. Decrease in the number of receptors
27
What is a drug holiday ?
This is when a patient takes some time off of taking a specific medication and it almost resets the body and lowers their tolerance to the drug .
28
4 main components of the respiratory system
1. Lungs
2. Diaphragm
3. Ribs
4. Nasal / oral cavity
29
What is the function of the cardiovascular system?
To pump blood around the body.
30
Name 3 conditions that can affect the cardiovascular system and how each affects the normal functioning of the system.
Hypertension - thicker blood vessel walls.
Angina - reduced blood flow to the heart
Arrhythmias - an abnormal heart rhythm.
31
How do beta blockers work
They are known as beta adrenergic blocking agents are medications that reduce your blood pressure
32
What are the adverse effects of beta blockers
Anaphylaxis
Skin rash
Blurred vision
33
What is the main function of the respiratory system?
To allow us to breathe and our body to absorb oxygen .
34
Name 1 condition that can affect the respiratory system and how it affects the normal functioning of the system
Asthma and it typically affects the bronchi and creates inflammation and excess mucus within the walls causing less air to pass through .
35
How does salbutamol treat asthma
It is a small molecule drug that acts as an agonist to beta -2 adrenaline receptors present in airway smooth muscle cells
36
What are the adverse effects of salbutamol
Anaphylaxis
Rash
Blurred vision
Arrhythmias
37
What is the function of the gi system
To allow the body to break down and digest food then later to excrete the waste matter left that isn’t needed or couldn’t be absorbed
38
Name three disorders of the GI system
Constipation
Diarrhoea
Heartburn/ indigestion
39
Which type of medication can treat constipation
Bulk forming
Osmotic
Stimulant
40
Which type of medication can treat diarrhoea
Anti diarrhoeal tablets
41
Which type of medication could be used to treat heart burn
Antacid or alginate or both combined
42
How do H2 antagonists work to treat an ulcer
They stop the blood clot from rupturing so it allows the body to heal it basically just allows the body to do its own healing
43
What are the adverse effects of cimetedine
Anaphylaxis
Rash
Hypotension
Gynaecomastasia
44
What is the function of the endocrine system ?
It is responsible for organs and glands releasing hormones to allow the body to regulate.
45
What is hypothyroidism
An under active thyroid is when your thyroid gland doesn’t produce enough of the thyroxine hormone.
46
What is Hyperthyroidism
Is an overactive thyroid which when your thyroid gland produces too much thyroxine
47
How does methimazole treat hyperthyroidism
Methimazole is a small molecule drug that works by competively inhibiting the enzyme peroxidase
48
What are the adverse effects of methimazole
49
How does the kidney perform osmoregulation
Blood water levels are sensed by the brain in the hypothalamus
When water levels are too low the hypothalamus gets the pituitary gland to release adh into the bloodstream
Cells in the collecting duct of the nephrons of the kidney have receptors for ash
50
What are three types of diuretic
Thiazide
Loop
Potassium sparing
51
How does indapamine work
It’s a small molecule drug that is an antagonist for the Na +/Cl- co-transporter in the wall of the proximal convoluted tubule
52
What are the adverse effects
It can affect the osmotic balance in your body
Anaphylaxis
Rash
Arrhythmias
Cardiac arrest
53
How does producing more urine help relieve high blood pressure
It reduces the amount of fluid in the blood vessels
54
What are the four mechanisms by which antibiotics can target bacteria
Disrupt membranes
Anametabolites
Inhibition of nucleic acid synthesis
55
What is the difference between gram positive and gram negative bacteria ?
First gram scaling
Gram positive- appear purple due to the peptidoglycan layer .
Gram negative - appear pink due to the extra layer of membrane and there isn’t enough peptidoglycan.
56
3 symptoms for a person suffering from schizophrenia
Hallucinations
Voices in their head
Losing interest in everyday things
57
Is dicloxacillalin bacteriocidal or bacteriostatic
Bacteriocidal
58
What is the mechanism of action of dicloxacillin
It works by affecting gram positive bacteria and works by destroying the structure of the cell wall
59
What are the adverse effects of dicloxacillin
Anaphylaxis
Diarrhoea
Precursors for white blood cells destroyed- neutropenia
60
What does dopamine normally do in the brain ?
Dopamine is the ‘pleasure neurotransmitter’ and the release of planing typically makes a person feel pleasure and happiness
61
What does dopamine normally do in the brain ?
Dopamine is the ‘pleasure neurotransmitter’ and the release of planing typically makes a person feel pleasure and happiness
62
What is the mechanism of action for risperidone
It is a small molecule drug that is an antagonist for D2 (dopamine) and 5-HT2A (serotonin)
receptors in the brain
If you block the detection of dopamine you help someone with schizophrenia with
any 'positive' symptoms where they see or hear things
If you block the release of serotonin it helps with their 'negative' symptoms
63
What are the adverse effects of risperidone
Allergy - immunological response
Hyperprolactenimia
Neutropenia
64
What condition does risperidone treat ?
Schizophrenia
65
Describe the process of DNA replication
1. DNA helicase unzips the dna
2. DNA nucleotides bind to their complementary bases on both strands
3. DNA polymerase then catalyses the formation of phosodiester bonds between adjacent nucleotides.
66
Define mitosis
The duplication of dna and reproduction of new cells via division
67
Describe the stages of mitosis
Prophase - replication of chromosomes
Metaphase - lines up in the middle of the cell
Anaphase - the chromatides pulled apart by spindle fibres
Telophase - two nuclear membranes form around chromosomes
68
Define malignant and benign
Malignant tumours are typically fast growing and harmful to the body and usually cancerous
Benign Tumors typically aren’t too concerning and don’t grow as fast
69
What is the cell cycle
The life cycle of the cell and how it divides
70
What are the stages in the cell cycle
G1
Synthesis
G2
Mitosis
71
What are the function of the checkpoints
To stop abnormal cells from dividing and producing new uncontrollable cells
72
What are the hallmarks of a cancer cell
They ignore stop signs and create their own go signs and divide uncontrollably
73
What is a mutation?
A dna sequence changes
74
What do oncogenes do ?
Oncogenes are genes that, under normal circumstances, tell cells to multiply and divide. In adults this doesn't happen very often.
We can think of oncogenes as being a bit like the accelerator pedal in a car. When they become active they speed up a cell's growth rate. When one becomes damaged, it is like the accelerator pedal becoming stuck down. That cell, and all the cells that grow from it, are permanently instructed to divide. So a cancer develops.
75
What do tumour suppressor do ?
It is usual for cells to repair faults in their genes. When the damage is very bad, tumour suppressor genes may stop the cell growing and dividing.
Mutations in tumour suppressor genes mean that a cell no longer understands the instruction to stop growing. The cell can then start to multiply out of control. This can lead to cancer.
The best known tumour suppressor gene is p53. Researchers know that the p53 gene is damaged or missing in most cancers.
76
What is a melanoma?
It’s typically a type of skin cancer and appears as a mole after sun exposure
77
What is a carcinoma
Carcinoma is cancer that forms in epithelial tissue. Epithelial tissue lines most of your organs, the internal passageways in your body (like your esophagus), and your skin. Most cancers affecting your skin, breasts, kidney, liver, lungs, pancreas, prostate gland, head and neck are carcinomas.
78
What is a sarcoma
A sarcoma is a rare type of malignant (cancerous) tumor that develops in bone and connective tissue, such as fat, muscle, blood vessels, nerves and the tissue that surrounds bones and joints. Symptoms depend on the tumor’s size and location. Treatments include surgery, radiation, chemotherapy, targeted therapy and immunotherapy
79
What is leukaemia
Leukemia starts when the DNA of a single cell in your bone marrow changes (mutates) and can’t develop and function normally. Leukemia cells often behave like abnormal white blood cells. Treatments for leukemia depend on the type of leukemia you have, your age and overall health, and if the leukemia has spread to other organs or tissues.
80
What does the word quantative mean ?
81
How is the calibration curve created ?
82
What are the limitations of quantitative Benedict’s test
83
What type of data can a quantitative test give us ?
84
What is colorimetry used to measure
85
What is the Benedict’s test used to detect ?
The Benedict’s test can be used to test
for the presence of sugars
86
What is the buiret test used to detect ?
The biuret test for proteins
is a qualitative test
87
What is colorimetry used to detect ?
• Measures the wavelength and frequency of the visible light absorbed. If this is
unique to substance, this can be used to identify that substance.
• Can also determine the concentration of a sample.
88
What is spectrophotmetry used to detect ?
A method to measure how much a chemical
substance absorbs light by measuring the
intensity of light as a beam of light passes through
sample solution. The basic principle is that each
compound absorbs or transmits light over a
certain range of wavelength
89
What is turbidmetry used to detect ?
Turbidimetry is commonly used to measure the number
of cells in a solution.
90
What is nephelometry used to detect ?
Nephelometry is a technique used in immunology to determine the
levels of several blood plasma proteins.
91
Benedict’s test method
Add 1cm3 of the sample then add 2cm3 of Benedict reagent and heat it up until an insoluble precipitate is formed.
92
Buiret test method
place the test solution in a test
tube and add an equal volume of
biuret solution
Biuret solution is a mixture of
sodium hydroxide and copper(II)
sulphate
93
Colorimetry method
Colorimetry is a method of analysis involving
the quantitative measurement of colour.
2) A colorimeter is a device that measures
the strength of a coloured solution by seeing
how much light passes through it.
94
Spectrophotometry method
When you have a sample that is a liquid with
cells floating in it, it is called a suspension.
1- some of the light will be absorbed by the particles
2- some will be transmitted through the suspension.
3- some will be scattered in various directions.
If we shine a light (or laser) through it 3 things
can happen
95
Turbidmetry method
Turbidimetry is the process of measuring the loss of intensity of
transmitted light due to the scattering effect of particles suspended in
it. Light is passed through a filter creating a light of known wavelength
which is then passed through a cuvette containing a solution.
96
Nephelometry method
It is based on the principle that a dilute suspension of small particles
will scatter light (usually a laser) passed through it (rather than
absorbing it). The amount of scatter is determined by collecting the
light at an angle (usually 30 or 90 degrees).
97
Benedict’s test limitations
This is only semi-quantitative – it cannot tell us the actual amount of sugar.
It is not very specific as it tests for all reducing sugars not just glucose specifically.
It is very sensitive and can determine the presence of reducing sugars with 97% accuracy.
98
Buiret test limitations
This is only qualitative – it cannot tell us the amount of protein.
It is not very specific as it tests for all dipeptides or polypeptides not a named protein
specifically.
It is very sensitive and can determine.
99
Colorimetry limitations
Cannot be used colourless compound.
If the wrong wavelength of light is used you
won’t get an accurate result
Can only be used in the visible light
spectrum
100
Spectrophotometry limitations
Limitations of spectrophotometry include a relatively low sensitivity and selectivity. It may thus be difficult to detect very low concentrations of an analyte or distinguish the analyte from other substances that absorb light on the same wavelength.
101
Turbidmetry limitations
Because turbidity measurement is carried out by measuring scattered light at 90o to the incident light, at low levels of turbidity, the detector is picking up a very small signal. Any bubbles present, especially micro bubbles, lead to a large amount of noise and the operator's accusation of “variable results.
102
Nephelometry limitations
Nephelometric methods may also be subject to interferences caused by particles or pigments in serum (e.g., lipemic or icteric samples) that increase background light scatter and make interpretation difficult or impossible.
103
Define sensitivity
Sensitivity refers to a test's ability to
designate an individual with disease
as positive.
A highly sensitive test means that
there are few false negative results,
and thus fewer cases of disease are
missed.
104
Define specificity
The specificity of a test is its ability to
designate an individual who does not have
a disease as negative. A highly specific test
means that there are few false positive
results.
105
Describe false positive and negative results
True negative = tests says negative and you don’t have it
False negative = test says negative and you do have it
True positive = test says positive and you do have it
False positive = test says positive and you don’t have it
106
Explain what expected range means and how doctors use them in diagnosis
Expected range is a piece of data that shows what the normal ranges are for that test and for the person of that age , size and sex and it helps doctors see what the patient is making ie not enough red blood cells etc
107
Describe the positive result for the three flame tests
Sodium = yellow
Potassium = lilac
Calcium = orange / red / bricky colour
108
Describe the limits of the flame tests
The wood burning could become an issue when testing for calcium and other substances that present as a orange flame when under heat.
The person may see the colour differently to others etc
109
Name the different types of leukocyte
Lymphocyte
Monocytes
Neutrophil
Eosinophil
Basophil
110
Draw a diagram of each type of leukocyte
111
Describe how a platelet count is carried out
By drawing blood and smearing it onto a glass slide then placing it under a microscope and then counting how many platelets are in that 1 um of blood
112
What does a full blood count include ?
counts the total number of red cells, white cells and platelets in the sample.
113
What does reference/expected range mean?
A set of values that a doctor uses to interpret a patient’s test results
114
Give some examples of conditions that may be diagnosed by a full
blood count, and the results that would indicate someone has them
Leukaemia- very low wbc
Polycythemia - haemoglobin levels are higher than expected
115
What is a haemocrit a measure of ?
Haematocrit is a measure of how many red blood cells a
patient has, in comparison to all of the other
components in blood
116
What is Haemoglobin and what does it do ?
Haemoglobin is the chemical within the erythrocytes
that actually binds to the oxygen.
117
How is a haematocrit carried out in a chemical lab ?
Blood is taken from a patient, loaded in to a very thin capillary
tube then spun in a centrifuge to separate the components
based on their mass. The PCV is calculated as a % of the total
blood volume
118
What does RIA measure ?
Radioimmunoassay (RIA) is a very sensitive technique that can be used to
measure low levels of antigens by use of antibodies.
119
What are the steps to carry out an RIA ?
In a
RIA a known quantity of an antigen is made radioactive, and mixed with a
known quantity of antibody and the two specifically bind together. A sample
from a patient containing an unknown quantity of the same antigen is
added. This causes the unlabelled antigen from the patient sample to
compete with the labelled antigen for antibody binding sites. A higher
concentration of unlabelled, patient antigen, displaces more labelled antigen
from the antigen - antibody complex. Bound antigens are separated from
unbound antigens and the radioactivity of the bound antigen remaining is .
120
What can ELISA measure ?
• ELISA is used to detect antigens or antibodies.
121
What are the steps in carrying out an ELISA ?
Direct ELISA - Patient sample is added to a multi-well plate and given
time/treated to make any antigen adhere to the surface, The plate is washed with a non-reactive protein like bovine (cow) serum
proteins to block any open space in the plate.
Indirect - A Antigens we want to test for in a patient sample are attached to a
surface (usually a multi-well plate),. A solution containing enzyme labelled antibodies is added to the
plate, a substance containing the enzyme’s substrate is added. The subsequent reaction produces a detectable signal, most
commonly a colour change. The higher the concentration of antigen, the stronger the colour
change, which can then be detected by a spectrometer
122
What are enzyme assays used to measure ?
Enzyme assays are performed to serve two different
purposes: (i) to identify a special enzyme, to prove its
presence or absence in a distinct specimen, like an organism
or a tissue and (ii) to determine the amount of the enzyme in
the sample”
123
What is the difference between an end point and a kinetic assay ?
• They measure either the consumption of substrate or formation of
product over time.
• These assays may be continuous, where the assay gives a continuous
reading of activity, (KINETIC)
• or discontinuous, where samples are taken, the reaction stopped and
then the concentration of substrates or products are
determined.(END POINT)
124
What are the limitations of enzyme assays ?
Sensitivity - Very sensitive
Specificity - Not very specific
Human error
Not following standard procedure
Misleading results
Interfering agents
Instability of enzymes during storage
125
What is the main staining technique and how does it work ?
All slides are routinely
stained with
haematoxylin and eosin
(H&E) and then
coverslipped to make a
permanent record of the
sample. Wh hat structures are stained purple?
DNA (heterochromatin and the nucleolus) in the nucleus, and RNA in ribosomes and in the rough endoplasmic
reticulum.
Some extracellular materials (i.e. carbohydrates in cartilage)
What structures are stained pink?
Most proteins in the cytoplasm. This includes cytoplasmic filaments in muscle cells, intracellular membranes,
and extracellular fibres.
126
What is immunochemistry and what does it look like ?
This technique stains slides using labelled antibodies
against certain tumour markers (like ELISA)
127
What is immunofluroescene and what does it look like ?
Immunofluorescence is the same, but
using fluorescent antibodies
This does not make permanent samples
128
Why would a lab do a frozen section ? And how are they different?
Some situations require an adapted approach to histology
When time is critical a frozen section can be made from a
piece of tissue – freeze at -70°C then section, hand stain with
H&E
This could be necessary if a surgeon needs
to confirm which tissue has been removed
before an operation can finish eg when
removing the parathyroid gland which is
really hard to locate.
129
What does crystallography look like?
Crystallography looks for crystal deposits in fluids (usually joint
fluid) using polarised light
Joint fluid under normal light
Joint fluid under polarised light showing
uric acid deposits – diagnosis of gout.
130
What are the basic principles of chromatography and what can it be used for in a clinical lab ?
All the types of chromatography are used to seperate different substances and measure them to work out unknown substances such as different types of drugs and to see if someone has taken them .
131
What is TLC and what is the mobile phase and what is the stationary phase ?
This is carried out using a
medium of silica powder spread
over a glass slide.
• An organic solvent carries the
pigments up the plate.
Mobile phase - solvent
Stationary phase - silica powder on the glass slide
132
What is HPLC what is the mobile and stationary phase ?
There is a column packed
with small beads of the
stationary phase.
The mobile phase is
pumped through the
stationary phase.
The sample is detected.
It can detect the
chemical and the amount
that is present.
133
What is GC and what is the mobile and stationary phase ?
• Used to separate complex mixtures
• Very sensitive so can detect small values
• Not only detects which chemicals but how much of each.
• Stationary phase = thin film of liquid inside the oven
• Mobile phase = gas ie helium (carrier gas)
• As compounds come out, they are detected and identified
using standards.
134
What is the purpose of aseptic technique ?
When an organism is being grown it is important to exclude others
that may harm it.
• Because microorganisms are widespread, equipment needs to be
sterilised in order to prevent contamination
• Working in this way is known as using aseptic technique
135
What are the main principles of aseptic techniques ?
When an organism is being grown it is important to exclude others
that may harm it.
• Because microorganisms are widespread, equipment needs to be
sterilised in order to prevent contamination
• Working in this way is known as using aseptic technique
136
What is a disinfectant ?
A substance capable of destroying
or inhibiting microorganisms
137
What does the gram stain tell us about bacteria ?
Whether the bacteria is gram positive or gram negative .
138
What are the steps in carrying out a gram stain ?
1. Wipe slide with ethanol
2. Place Bunsen burner on roaring flame and scrape bacteria off of the Petri dish with a sterile loop.
3. Place bacteria on slide and mix it about with a drop of water.
4. Wait for it to dry place under flame three times.
5. Turn flame off and place slide in the tub on frame and wash it with crystal violet then wash with iodine then wash with water and place the saffron in on top then wash with water and allow to dry and then place under microscope and analyse.
139
What other biomedical tests can we use to identify bacteria ?
Carbohydrate fermentation
Oxidase test
Catalase test
140
What does PCR stand for ?
Polymerase Chain Reaction (PCR)
141
What are the stages of PCR ?
142
What temperature is required for each stage ?
94,72 and 55
143
What is the end product of PCR ?
More DNA replicated
144
