Biol131 Flashcards
1
Q
When making a diagnosis , what is checked in the blood?
A
Biochemical markers, cell abnormality
2
Q
When making a diagnosis, what is checked in urine/faeces?
A
Clinical chemistry, cytology
3
Q
When making a diagnosis, what is used for biopsy tissue?
A
Direct histological examination
4
Q
An ultrasound/ sonogram uses….. to produce an image?
A
High frequency sound waves, at a low resolution
5
Q
What does a CT scan use? Fast or slow? Is it detailed?
A
X-rays to quickly produce an image with less detail
6
Q
What does an MRI scan use to produce images? Faster or slower than CT? More or less detailed?
A
Radio waves and strong magnetic fields, slower than CT, more detailed than CT
7
Q
What is histology?
A
The study of the structure of animal and plant tissues as visualised
8
Q
What is cytology?
A
The microscopic appearance of cells under the microscope
9
Q
What is a neoplasm?
A
New growth of cells
10
Q
Which cells do not respond to regulatory signals?
A
Cancer cells
11
Q
Briefly describe neoplastic transformation? Are tumour cell growths that are well differentiated or less differentiated more aggressive?
A
Cells becoming less differentiated, more like precursor cells. Less differentiated = more aggressive as they are less like normal cells
12
Q
What are features of the atypical cytology of neoplastic cells?
A
1) pleomorphism (change in shape or size) of cells and nuclei
2) increase in hyperchromatism (increased nuclear staining)
3) increase in size of nucleus
13
Q
What is metastasis?
A
Invasion of the tissue away from the original tumour growth via the lymph/ blood
14
Q
Above 2mm = ……….. environment, so the tumour produces its own blood supply
A
Hypoxic
15
Q
Dysplasia
A
Abnormal growth or development
16
Q
What are the techniques for obtaining a tissue sample?
A
Needle biopsy, endoscopic biopsy, incisional biopsy, excisional biopsy, resection
17
Q
What is a needle biopsy? what is it used for?
A
Uses cutting needle to take a 1-2 mm wide 2cm long bit of tissue from anywhere even brain lesions
18
Q
What is an endoscopic biopsy?
A
Uses small forceps to take a 2-3 mm sample from the GI , respiratory, urinary and genital tracts
19
Q
What does an incisional biopsy use?
A
A scalpel
20
Q
What is removed in an excisional biopsy?
A
The whole lesion
21
Q
What is a resection?
A
A large tissue sample
22
Q
What are the techniques to obtain cell samples?
A
Shed naturally into bodily fluids, aspiration with a needle, exfoliation using a brush
23
Q
How is a smear test done?
A
1) scrape cells from ectocervix and lower cervical canal with a spatula/brush
2) fix onto a slide and stain
3) looking for CIN ( cervical intraepithelial neoplasia)
24
Q
What has helped to decrease the risk of cervical cancer?
A
HPV vaccination
25
Adenoma
A tumour of epithelial origin, that is not cancer.
26
Anaplasia
Reversion of cell to primitive/undifferentiated state
27
Angiogenesis
New blood vessel growth.
28
Apoptosis
A type of cell death in which a series of molecular steps in a cell lead to its death.
29
Benign
Neoplastic growth (tumour) that is not cancer.
30
Carcinogen
- a substance, organism or agent capable of causing cancer.
31
Carcinoma
Cancer that originates in epithelial (lining) cells.
32
Dysplasia
Abnormal growth or development
33
Hyperchromatism
increased staining, usually due to more dense structure.
34
Hyperplasia
increase in number of tissue cells due to increased cell division
35
Hyperproliferation
increased rate of cell proliferation
36
Hypertrophy
increase in size of existing cells, matched by increase in functional capacity
37
Malignant neoplasm
Tumour that invades surrounding tissue/Tendency to metastasize
38
Neoplasia
Uncontrolled abnormal growth ( benign or cancerous)
39
What causes squamous metaplasia in the transformation zone of the cervix?
The columnar epithelium is exposed to a hostile environment causing more growth of stratified squamous epithelium
40
What is needed on the slide when using a magnification of more than x40
Oil immersion
41
What is the magnification and resolution of a light microscope?
X1000 magnification, 200nm
42
What is the magnification and resolution of an electron microscope?
X1x106
0.2nm
43
What is a disadvantage of staining specimen?
Requires fixing , cells usually have to be dead
44
How does Phase-contrast and Nomarski microscopy allow for examination of living , unpigmented cells?
Amplifies variations in density within specimens
45
What is fluorescence used for in light microscopy? Do teh fluorescent molecules usually exist naturally?
Shows the locations of specific molecules in the cell. The fluorescent substances absorb short wavelength radiation, UV, and wemit longer wavelength radiation ( visible light). They are usually added by tagging.
46
What is the most common stain used in hospital pathology labs?
H and E ( Haemotoxylin and Eosin
47
What are the problems with processing and histology ?
1) processing alters structures and can introduce artefacts
2) only gives a snapshot of dead cells
3) 2D image of 3D structure
48
Describe histology start to finish?
1) Specimen dissected
2) Fixation
3) Dehydration
4) Embedding
5) Sectioning
6) Staining
49
What is a common fixative ? What does it do?
Formaldehyde
Arrests biological activity, prevents tissue degradation (autolytic degradation, bacteria)
50
What process is required prior to embedding?
How do we embed?
Dehydration to prevent issue damage
Support the tissue by embedding in a hard medium such as paraffin wax, freezing or a plastic resin
51
What are the 3 methods for tissue sectioning ?
Cryostat, microtome, vibratome
52
With a cryostat method of sectioning , how are tissues preserved? What is the thickness?
Frozen
10-40 micrometers
53
With a microtome, what are tissues embedded into? What thickness?
Wax
5-40 micrometers
54
With a vibratome how are samples attached? What thickness?
They are glued to the holder, 40-400 micrometers
55
Haematoxylin stain , stains acidic structures what colour?
Purplish blue
56
with Eosin staining what colour are basic structures shown?
Red/pink
57
Massons trichome stains …….. tissue ?
Nuclei stains ….
Connective tissue stains ….
Cytoplasm stains …..
Connective tissue
Nuclei goes purple/pink
Connective stains blue
Pink/red
58
Periodic acid-Schiff rxn stains complex carbs what colour ?
E.g Mucin in the …….cells in the intestine
Purple /magenta
Mucin in the goblet cells
59
What describes the use of antibodies to label a specific protein or cell?
Immunohistochemistry
60
What is the function of simple columnar epithelium?
Absorptive / secretory surfaces
61
What is the function of stratified epithelia?
Protective function
62
What is the purpose of elongated cells in smooth muscle tissue?
To maximise contractile properties
63
Which type of cells migrate up the crypt in the colon?
Stem cells
64
What are some of the features of dysplasic colon?
Villiform change of epithelium
Crypt budding, branching, and crowding
Irregularity of crypt contour
Increased angiogenesis
65
In a normal prostate, what proportion of the cells are luminal cells and what proportion are basal cells?
60% luminal , 40% basal
66
What are some of the features of prostate cancer, regarding the histology?
Luminal hyperproliferation, loss of the basal layer, breakdown of the basal membrane , immune cell infiltration and stromal reactivity
67
Give a type of cell that does not regenerate?
Cardiomyocytes
68
What changes can cause cellular stresses?
Osmotic stress( water and electrolyte concentrations) , temperature stress, oxygen deprivation, infection, pH changes
69
What are some examples of adaptive responses during cellular stress?
Metabolism :
During fasting fatty acids are mobilised from adipose tissue
Calcium can be sourced from bone matrix
Liver enzymes can metabolise drugs
Metaplasia
Genes:
Housekeeping gene expression decreases
Cell stress gene expression increases e.g heat-shock proteins
70
What is the function of heat-shock proteins?
“ chaperones” for protection, assist in refolding, and preventing protein aggregation ( clumping)
71
What is Ubiquitin useful in?
Targeting proteins for destruction
72
During cellular stress: increased functional demand may result in………
Give an example for each
Hyperplasia , hypertrophy
Endometrial lining during menstrual cycle
Skeletal muscle fibres of athletes
73
How can transient epithelial hyperplasia be a benefit when infected with a pathogen?
It can help to expel intestinal pathogens
74
Is BPH (benign prostatic hyperplasia) a risk factor for prostatic carcinoma?
No
75
In which method of cell death is membrane integrity NOT maintained?
Necrosis
76
What are the phases of Apoptosis?
1) Induction/signalling + cell shrinkage/ chromatin condensation
2) Effector- mitochondrial permeability - no return point
3) Degradation - membrane blebbing , organelles disintegrating due to proteases - forms apoptotic bodies
4) Phagocytosis- cell fragments are engulfed and removed
77
Give 2 examples of beneficial apoptosis
Removal of autoreactive immune cells
Intestinal cell turnover
78
What are the triggers of necrosis ?
Metabolic stress, hypoxia ( lack of oxygen) , absence of nutrients, trauma
79
What molecular mechanisms can result in necrosis ?
- reduction in ATP , internal membranes can swell, dec biosynthesis
- cytosolic calcium increases activating protein kinases and phospholipases
- reduction in ability to scavenge reactive oxygen species ( ROS)
- plasma membrane integrity and cytoskeleton compromised
- cell swelling , lysis or bursting as this can cause inflammation
80
What chemical agents are examples of chemicals that can cause necrosis?
CCl4 , paracetamol
81
Describe how ischemia ( restriction in blood supply ) leads to necrosis. Where does this become irreversible?
- Anaerobic metabolism
- Failure of ionic pumps leading to cellular swelling
- accumulation of metabolic intermediates leading to cell damage . Till now is reversible
- Necrosis
82
Reintroduction of oxygen ( reperfusion) can cause further damage , how?
-Inflammatory response
-Oxidative stress
- Further ionised calcium influx
- more cell damage
83
Which cell death process requires ATP and which is passive? Which involves cytoplasm shrinkage and which involves swelling?
Apoptosis is active , necrosis is passive. Apoptosis- shrinkage. Necrosis- swelling
84
After gel electrophoresis what is the difference between teh DNA after apoptosis and necrosis?
Apoptosis- non-random degradation ———ladder
Necrosis - random DNA digestion ———— smear
85
What are the 2 outcomes after cell death following tissue damage ?
Restitution- if cells can regenerate
Fibrous repair and scar tissue formation
86
Which type of inflammation is a normal healthy temporary process designed to eliminate damaging stimuli and heal damage?
Acute
87
When does chronic inflammation occur?
When the stimulus cannot be removed and in inflammatory process persists becoming damaging to the host tissues
88
What are the 4 cardinal effects of acute inflammation
Rubor( redness), Calor( heat), Dolor(pain), Tumor (swelling)
89
What do chemical mediators stimulate the production of ?
Acute inflammatory exudate
90
What happens to the damaged tissue after the exudate has reached the damaged area?
The damaged tissue is broken down, partly liquefied and the debris is removed from the site of damage
91
What are the components of acute inflammatory exudate ?
-salt containing fluids and proteins
-fibrin (insoluble protein)
-neutrophils (phagocytic cells)
-macrophages ( produce cytokines)
-dendritic cells (present antigen to T cells)
- Lymphocytes ( T cells)
92
Why does the blood flow become slower and the blood vessels dilate?
To increase blood at injury site
93
What word describes how water, salts and proteins leave vessels?
Exudation
94
What word describes the way in which Neutrophils ( then monocytes) squeeze between the endothelial cells?
Transmigration
95
What are the stages of transmigration of leukocytes during inflammation?
1) tethering and rolling
2) Activation
3)Firm Adhesion
4)Transmigration
96
What are leukocytes attracted by during transmigration ?
What is a synonym for transmigration ?
Chemokines and cytokines released by tissue macrophages
Diapedesis
97
What do leukocytes do to help themselves to move between the endothelial cells of veins and migrate into the tissue?
Form pseudopodia and produce proteases to help move between endothelial cells of veins and migrate into the tissue
98
Monocytes become ……. In tissue
Macrophages
99
Neutrophils are the main effector cells of which response?
The acute response
100
What part of the cellular response is conducted within minutes?
Monocytes and macrophages secrete cytokines
101
What do cytokines do ( immune response)?
Trigger the adaptive immune response , they activate B and T cells
102
How does acute exudate leave the tissue?
- lymphatic system , stimulate adaptive immune response in lymph nodes
103
Which type of white blood cell does not recirculate?
Neutrophils , stay at site as pus build up
104
What are the histological features of chronic inflammation?
- necrotic cell debris
- acute inflammatory exudate
- vascular and fibrous granulation tissue
- lymphoid cells and macrophages
- collagenous scar
105
What is the main effector cell of chronic inflammation?
Macrophages
106
What is the name for the discrete clusters formed from macrophages?
Granulomas
107
How does TB evade the acute immune response?
It invades, and replicates within macrophages
108
What are the given examples of receptors that trigger the innate immune response?
PAMPs (Pathogen-associated molecular patterns)
DAMPs (Damage-associated molecular patterns)
109
Is immunodeficiency inherited or acquired?
Can be either or can be from damaging stimuli e.g radiation and chemotherapy
110
What can sustained irregularities in white blood cell counts indicate?
Inc- leukaemia
Dec- immunodeficiency
111
What is immunophenotyping used for ? What are the 2 ways that expression can be detected?
To study protein expression on cells
Microscopy , flow cytometry
112
Which method ( microscopy or flow cytometry ) allows you to examine multiple cell types at the same time? Which allows tissue to be preserved during processing?
Flow cytometry
Microscopy
113
What are the 3 levels of fungal ( mycoses) infection ?
Superficial ( skin, hair) , cutaneous and subcutaneous (nails and deeper skin) or deep mycoses (internal organs)
114
Where are protist diseases most prevalent?
How are they transmitted?
Parasites can be ……….. or …………..
What is the usual type of reproduction ?
-Tropical and subtropical regions
-Bites of blood sucking insects or accidental ingestion of infective stages
- Intracellular or extra cellular
- Asexual reproduction
115
How do we classify viruses?
- type of nucleic acid
- mode of replication
- symmetry of virus particle - icosahedral , helical or complex
- presence or absence of an external envelope
- identification using antibodies to certain features (epitopes) , serologic reactivity or PCR amplification of viral DnA
116
Why are histological fixatives not used for medical microbiology?
It kills the microbes
117
Give some example of body sites which are usually sterile?
Blood and bone marrow , cerebrospinal fluid, serous fluids, tissues, lower respiratory tract , bladder
118
Which body sites have a normal commensal flora?
- mouth and nose
-upper respiratory tract
- skin
- gastrointestinal tract
- female genital area
- urethra
119
What are some examples of acute lower respiratory tract infections?
Bronchitis , pneumonia and influenza
120
What are some examples of chronic lower respiratory tract infections?
Tuberculosis, aspergillosis , lung abscesses , infections in cystic fibrosis
121
How does pneumonia infection occur?
- inhalation of aerosols
- aspiration of normal flora
- via the blood
122
Tubercles may heal spontaneously , become …….. or calcified and persist (dormant) in otherwise healthy people
In the immunocompromised the mycobacteria invade the bloodstream leading to often fatal “……….” TB
Fibrotic
Military
123
What is epidemiology ?
- the study of factors ,implicated in disease progression , that determine its frequency , distribution and severity in cohorts of individuals
124
What is the epidemiological triangle of causal factors?
- external agent
- a susceptible host
- an environment that brings the host and agent together
125
Epidemiological triangle
Give 3 examples of agents ?
Bacteria , viruses , pesticides
126
Define endemic , given an example
Define epidemic
Diseases that occur at a constant rate within a given population like chicken pox
Incidence of disease above the endemic rate e.g measles outbreak
127
What is the biggest risk factor for cancer? What % of cancer related deaths can be avoided? In terms of no. deaths what is the deadliest event in history ?
-Age
- 30%
- AIDS
128
What is the difference between antigenic drift and shift?
Antigenic shift is where 2 viruses enter and both genes and antigens from both viral types are incorporated into new proteins so the change is more severe, the new virus is very different .
Antigenic drift is where mutations occur so the new virus is slightly different
129
Causal pies are a good way of studying non-communicable diseases like cancer, when does disease occur in this model?
- Once all the pieces of the pie are present
130
Sickle cell anaemia is more common in people of what origin? What about Tay-Sachs disease?
- African or Mediterranean
- Ashkenazi ( eastern and Central European) Jewish or French Canadian ancestry
131
Sickle cell anaemia is more common in people of what origin? What about Tay-Sachs disease?
- African or Mediterranean
- Ashkenazi ( eastern and Central European) Jewish or French Canadian ancestry
132
Sickle cell anaemia is more common in people of what origin? What about Tay-Sachs disease?
- African or Mediterranean
- Ashkenazi ( eastern and Central European) Jewish or French Canadian ancestry
133
Why does migration have an effect on cancer rate?
- carcinogens of dietary or environmental origin play the most significant role in cancer causation rather than genetic background ( Japan / Hawaii migration study)
134
Why are tests needed ( clinical biochem)? To see if a tumour has been successfully removed what can we check for?
- diagnosis
-monitoring of treatment
-disease screening
- prognosis
- tumour markers in blood
135
What are the most common sample types in clinical biochem?
when no anti-coagulant is added and the sample is centrifuged , what is the top layer? What if it is added?
- serum from venous blood or urine
- serum
-plasma
136
What is the red blood sample tube ?
Yellow?
Purple?
Green?
Heparinized Syringe
- no anticoagulant, clot, general
- SST gel to separate serum, general
- EDTA anticoagulent, whole blood analysis , red cell analysis , lipids and lipoproteins
-lithium heparin anticoagulent
- fluoride oxalate, glucose and lactate testing
- arterial blood sampling
137
What other specimens can be used in clinical biochem other than venous blood and urine?
- arterial blood
- faeces
- CSF ( cerebrospinal fluid)
- sweat ( used in cystic fibrosis diagnosis )
- saliva (can test cortisol)
138
What is Pheochromocytoma?
Excessive adrenaline production
139
What are the stages in the biochemistry process?
- request form with clinical data
- patient sampled
-transit to lab
- reception and ID
-analysis
-quality control
- collation
- interpretation
-reporting
-answer
140
What is sensitivity?
- how little of the analyte can be detected by the assay
141
What is specificity?
-how good is the assay at discriminating between the requested analyte and other interfering substances?
142
What does infarction mean?
Death of tissue following lack of blood supply
143
What does morbidity mean?
The condition of suffering from a disease or medical condition
144
Coronary circulation:
In the left coronary artery what are the 2 branches and where do they deliver blood to?
In the right coronary artery what are the 2 branches?
-Circumflex branch - left ventricle and left atrium
- anterior interventricular branch - both ventricles
- posterior interventricular branch - both ventricles
- marginal branch- right ventricle
145
What are the 3 levels of structure in an artery?
Tunica Intima
Tunica media
Tunica externa
146
What causes a myocardial infarction ?
Supply of blood to coronary muscle reduced by a critical value usually due to atheromatous plaque rupture with overlying thrombosis
147
What is perfusion ?
Passage of fluid through circulatory or lymphatic system to organs
148
What are the risk factors for atheroma development ?
- toxins
- viruses
- hypertension
-smoking
- immune reactions
149
Describe the development of atheroma in coronary arteries
- initial damage to endothelium
- LDLs ( low density lipoproteins) enter the intima and taken up by macrophages
- fatty streak forms due to macrophages under endothelial cells
- macrophages release lipids into the Intima
- collagen released
- lipid plaque forms
-fibrolipid cap forms
-endothelium is fragile and ulcerates
-platelet aggregation which leads to thrombus formation
150
What are the consequences of atheroma ?
- artery narrowing
- thrombus formation
- bleeding into the plaque
- aneurysm
151
What is arteriosclerosis? Atherosclerosis?
- thickening and hardening of artery wall
- thickening and hardening of high pressure artery wall due to atheroma
152
How can an ECG show a diagnosis of MI? What is issue?
- an elevated ST region
- can take up to 24 hours to develop
153
What are some examples of enzyme cardiac biomarkers?
Creatine kinase (CKMB) - muscle damage, specificity issue
Lactate dehydrogenase -not used since 2000
Aspartate amino transferase (AST) - not since 2000
154
What are some muscle protein cardiac biomarkers for detecting MI?
- myoglobin ( issue as also in skeletal muscle)
- Troponin I (cTnI) -cardiac specific.
- Troponin T (CTnT) -cardiac specific
155
What are the 3 forms of Troponin ?
Troponin C - binds calcium and regulates the action of the filaments during contraction
Troponin I - Prevents contraction in absence of calcium and Troponin T - binds the complex to tropomyosin
156
What 2 types of cardiac Troponin when measured can indicate infarction?
CTnT and CTnI
157
What are the treatments of Myocardial Infarctions ?
- thrombolytic agents such as Streptokinase and Tissue plasminogen activase
-coronary angioplasty to remove obstruction and enable blood flow
-anticoagulants such as heparin
158
Give some core biochemical tests ?
-Us and Es (urea and creatinine and electrolytes )
-LFTs - liver function test (e.g bilirubin , albumin)
-Thyroxine and thyroid stimulating hormone
-H+, pCO2, pO2 ( blood gases)
-glucose
159
What components are checked as a U an Es test?
-sodium, potassium, urea, creatinine, chloride ,bicarbonate
160
When do serum urea and creatinine increase?
When the glomerular filtration rate is reduced
161
What is vasopressin another term for? What does it do?
What does aldosterone?
- ADH
- Causes reabsorption of water in collecting ducts
-Causes reabsorption of sodium in nephron and hence water
162
What is the normal sodium range? Where is the major site of sodium loss in non-renal associated disease?
-135-145 mmol/l
-GI tract
163
What is hypernatraemia? Causes? Clinical signs? How to treat?
-Na > 145mmol/l
-water depletion
-excessive sodium intake
-renal failure
-blood pressure decreased (or inc salt)
-dry mucous membranes
-oral water
IV 5% dextrose
164
What is hyponatraemia ? Causes for oedematous hyponatraemia? Treatment ?
-Na < 135mmol/l
-Heart failure
-dec in effective blood volume
-aldosterone and adh secreted
-salt and water retained
-diuretic and restrict fluid + treat condition
165
What are the causes of non-oedematous hyponatraemia? Treatment
-ADH released all the time (infection and malignancy )
-Syndrome of inappropriate antidiuresis (SIAD)
-Too much water absorbed by kidney
- Restrict fluid
166
What are the causes of hyponatraemia via sodium loss?
What are the clinical signs?
Treatment?
- vomiting , diarrhoea
-lack of Na intake
-lack of aldosterone
-Tachycardia
-Hypotension
-oral correction of sodium loss
167
What is the normal level of potassium in the blood?
What is the function of K+?
What can rapid changes in K+ cause?
-3.4-4.9 mmol/l
-Excitable cells (nerves and muscles) behave differently if K conc alters
-dangerous cardiac arrhythmias that can result in death
168
What are the example causes of hyperkalaemia ( >4.9mmol/l) ?
What are some example treatments ?
-Renal failure, adrenal failure, K+ released from damaged cells
-calcium gluconate
Insulin + glucose
Dialysis
169
Acute renal failure :
-What is Anuric and what is oliguric?
What are the biochemical findings?
What are some of the causes?
-Anuric ( no urine ) or oliguric (<400ml/day )
-Conc urine, serum urea and creatinine inc
-hyperkalaemia
-pre-renal - blood supply to kidney failure
-renal- damage to kidney tissue
-post-renal- obstruction blocks urinary disease
170
What are the biochemical findings of chronic renal failure?
What management is used?
-Hyperkalaemia - nephron can’t excrete K
-Serum urea and creatinine high
-sodium restriction
-diuretics
-dietary restriction of protein
-oral ion exchange resin (K removal)
-potentially dialysis or transplant
171
What mnemonic can help to remember symptoms of hypernatremia?
FRIED
F-fever, flushed skin
R-restless
I-Increeased fluid retention and BP
E-Edema
D-decreased urinary output , dry mouth
172
What mnemonic can help you remember symptoms of hyperkalaemia ?
MURDER
M-muscle weakness
U-Urine, oliguric, anuria
R-respiratory distress
D-Decreased cardiac contractability
E-ECG changes
R-reflexes , hyperreflexia or areflexia
173
What mnemonic can be used for causes of hyperkalemia?
MACHINE
M-medications, ACE inhibitors
A-Acidosis
C-Cellular destruction - Burns , traumatic injury,
H-hypoaldosteronism /hemolysis
I-Intake excessive
N-Nephrons , renal failure
E- Excretion - Impaired
174
What is the tunica Intima composed of in arteries?
Endothelium
Basement membrane
Internal elastic laminate
175
What is the tunica media composed of?
Smooth muscle
External elastic lamina
176
What is the tunica external composed of?
Elastic and collagen
177
What type of filament are cardiac biomarkers Troponin I and T present in?
Thin filament (actin)
178
What is coronary artery bypass grafting?
Grafing an artery or vein to the coronary artery to bypass any obstruction
179
What does a coronary angioplasty involve ?
A procedure used to widen blocked or narrowed coronary arteries by inserting a stent
180
What is the normal value for blood glucose ?
4.0 - 6.0 mmol/l
181
1 out of ……. People have Diabetes mellitus
11
182
What is MODY with respect to the young ?
Maturity onset diabetes of the young
183
What percentage :
Adults with type 1 DM
Adults with type 2
Children with DM
Children with type 1
Children with type 2
Children with mody
10
90
95
2
3
184
What can cause hypoglycaemia?
Hyperinsulinism
Glycogen storage diseases
185
What happens when blood sugar levels are low?
Too high?
-glucagon released from alpha cells
-Hepatocytes release glucose
-insulin released from beta cells
-glucose enters cells
186
How does the beta cell know when to release insulin? (Stimulus-secretion coupling)
-Glucose enters the beta cell
-Phosphorylation of the glucose
-Glycolysis
-Pyruvate formed
-ATP is produced
-The K channel closes
-K+ rises in cell
-membrane depolarisation
Calcium channels open, calcium rises in cell
-insulin granule exocytosis
187
What happens when insulin binds to its receptors
-Insulin binds to receptor ( tyrosine kinase) which is embedded into the membrane. It has 2a and 2b subunits
-Binding of insulin to the a subunits causes phosphorylation of the b-subunits thus activating the kinase activity.
-Results in glucose utilisation and further glucose uptake via a range of signal transduction pathways that increase the number of glucose transporters
188
What are the causes and onset age for type 1 and 2 diabetes mellitus?
Type 1:
-autoimmune mediated destruction of pancreatic beta cells which result in absolute insulin deficiency
-weak family trait (except 40% in identical twins)
- at 9-13 usually
Type 2:
- insulin resistance
-overeating, obsesity and lack of exercise
-strong family trait
-over 40 years old
189
What are the treatments for type 1 and 2 diabetes mellitus?
Type 1:
-insulin injection subcutaneously ( just under skin in fatty tissue)
-Pancreas transplant
Type 2:
-reduce calories
-sulphonylureas - beta cells secrete more insulin
-Bariatric surgery ( weight loss)
190
How can diabetes mellitus be diagnosed?
-urine glucose test ——> 10mmol/I glucose, overspill ( glycosuria)
-HbA1c
-Blood glucose
1) fasting blood glucose
2) random blood glucose (RBG)
3) oral glucose tolerance test (OGTT)
191
In the oral glucose tolerance test what happens?
Baseline fasting blood glucose levels are taken
A glucose drink is consumed
Measure the glucose in plasma every 30 mins for 2h
192
What does HAI stand for?
What does exogenous mean?
What does endogenous mean?
-Healthcare associated infection
-From another person or the environment
-From another site in the patient
193
What HAI used to come from physicians hands?
What are the most common HAIs in England?
Puerperal fever - uterine tissue infection
Pneumonia
UTI
Surgical site infection
Clinical sepsis
Gastrointestinal infections
Bacteraemia (bacteria in blood)
194
What HAI used to come from physicians hands?
What are the most common HAIs in England?
Puerperal fever - uterine tissue infection
Pneumonia
UTI
Surgical site infection
Clinical sepsis
Gastrointestinal infections
Bacteraemia (bacteria in blood)
195
What are the most important causes of HAI in England?
-E.coli (gram - )
-S.aureus (gram + )
196
What are the most important causes of HAI in England?
-E.coli (gram - )
-S.aureus (gram + )
197
Why is making sure antibiotic conc is high enough important /
-a low conc can stimulate bacterial mutation
198
What does MRSA stand for?
Methicillin-resistant Staphylococcus aureus
199
If c.difficile is a bacterium in normal gut flora why can taking antibiotics cause it to infect and have a high morbidity and mortality ?
-antibiotics kill other bacteria , so C.difficile inc, produces toxins, diarrhoea and pseudomembranous colitis
200
What does VRE stand for in terms of Hospital acquired infection?
-Vancomycin-resistant Enterococci
-it is in normal gut flora
201
What are the principles of the of the health care act 2006?
-patients must be cared for in a clean environment
-keep HAI risk as low as possible
202
How can we eliminate the source of infection to reduce HIAs?
-cleanliness
-sterile equipment
Dressings
IV fluid
Blood product screening
Bacterailly-effective handwashing
Immunisation
‘Bare below elbows’ policy
203
What are the environmental sources of infection for HAIs?
Food
Air
Dust
IV fluid catheters
Wash bowls and bed pans
Endoscopes
Ventilators and respiratory equipment
Water and disinfectants
204
What is the difference between sterilisation and disinfection ?
-Disinfection removes most but not all viable organisms but sterilisation removes all viable microorganisms including viruses and spores
205
What is the difference between sterilisation and disinfection ?
-Disinfection removes most but not all viable organisms but sterilisation removes all viable microorganisms including viruses and spores
206
How can we sterilise? Vs disinfectant
-heat 160-180 glassware
Autoclaves equipment and dressings
Irradiation - gamma for needles, gloves and vaccines
Filtration - fluids
Chemicals e.g glutaraldehyde for endoscopes
Chemical, boiling, low pressure steam
207
How can we interrupt transmission of infection (HAIs)?
Airborne :
Check air conditioning for legionella
Hospital operating theatre ultra clean air
Isolation nursing
Contact:
Aseptic behaviour
Handwashing +
Alcohol based Hand gels
208
Which people are at high-risk /susceptibility to infection ?
Very young and elderly
Lack of vaccination or previous exposure e.g chickenpox in adult
Immune defects such as diabetes or HIV
Immunosuppressive drugs
Lung, skin or urinary system disease (portals of entry for microbes)
Trauma e.g burns , surgery , IV access, urinary catheters
209
What measures can be taken to reduce risk factors for HAIs?
-prophylactic antibiotics ( preventative )
-care of invasive devices
-short pre-operative time
-minimum duration for operations
210
How is a surgical wound characterised?
Inflammation, pus, discharge
211
How can catheter infection be prevented ?
Cover insertion site , wash hands , wear gloves, single use disinfection wipes
212
How can HAIs be surveilled?
-microbiology reports
-ward rounds
-staff health records
-patient surveys after discharge
213
What is a complication of diabetes mellitus due to defective blood supply to neurons in feet ?
Diabetic tropic ulcers due to ischaemia in feet, poor healing
214
What is hyaline arteriosclerosis ?
What happens due to this glomerular damage ( diabetes) ?
-Thickening of glomerular capillary basement membrane due to a glycation of proteins
-Inc in permeability
-proteinuria - renal failure
215
What effects can diabetes have on the eyes?
Hyaline arteriosclerosis ; basement membrane thickening in retinal blood vessels
Retinal haemorrhage
Cataracts - glucose attaches to lens proteins causing cloudiness
216
What is arrhythmias ?
Abnormal / irregular heart beat
217
What is another name for ADH?
Vasopressin
218
Where is ADH released from ? And what does it do?
Pituitary gland
Causes reabsorption of water in collecting ducts
219
Where is aldosterone released rom? And what does it do?
Adrenal glands
Reabsorption of sodium in nephron and hence water
220
What is SIAD?
Syndrome of inappropriate antidiuresis
221
What is tachycardia?
Heart rate above 100 beats per minute
222
In non-renal associated diasease where is a common place for sodium loss?
GI tract
223
When you centrifuge a blood sample what 3 layers form?
Plasma 55%
RBC 45%
Buffs coat (wbc and platelets)
224
What are the components of blood plasma ?
Water
Electrolytes
Plasma proteins
225
What does blood transport?
Gases
Nutrients
Metabolic waste
Hormones
Antibodies
226
What term means development of blood cells?
Haemopoiesis
227
Where is red Bone marrow found?
Pelvis
Vertebrae
Sternum
Proximal ends of humerus and femur
228
What are 3 examples of granular leukocytes?
Eosinophil
Basophil
Neutrophil
229
What are the agranular lymphocytes?
Monocytes
T cells
B cells
230
What does a high neutrophil count mean? Low?
-potential bacterial infection
-drug toxicity
231
What does a high count of lymphocytes mean ? Low?
CLL (chronic lymphocytic leukaemia )
HIV
232
What does a high and low count of monocytes indicate ?
Viral/fungal
Bone marrow suppression
233
What does a high count of eosinophils mean? Low?
Allergic reaction , parasitic infections
Drug toxicity , stress
234
What does a high count of basophils?
Allergic reaction, leukaemia
Stress
235
What are haemoglobinopathies?
Abnormal Hb production
236
Why are sickle cells sickle shaped ?
GAG to GTG
Mutation from adenine to thymine causes a change in tertiary structure. R group goes to hydrophobic (valine) from negatively charged (glutamic acid has an extra COOH group )
237
What are the types of thalassemia?
There is a reduced synthesis of what ?
How do the erthrocytes stain?
Alpha / beta
Alpha or beta globin chains
Weakly with eosin (hypohromic)
238
What are the complications of wrong blood transfusion ?
-chest pain , vomiting
Iron overload
Infection
239
Type A blood has …..
Antigens
Antibodies in plasma can receive
A antigens
B antibodies
Receive type A or type O
240
Type B blood has …….. antigens
……antibodies
Can receive
B
anti-A
Receive B or O
241
What antigens does type O blood have ?
Anti-….. antigens ?
Can receive
none
Anti-A and Anti-B antigens
Recieve O blood
242
What does AB blood have ?
Receive ?
A and B antigens
No antibodies
AB, O, A, B
243
What is rhabdomyolysis
a condition that causes your muscles to break down (disintegrate), which leads to muscle death
244
Hypovolemic shock
severe blood or other fluid loss makes the heart unable to pump enough blood to the body
245
Hypovolemic shock
severe blood or other fluid loss makes the heart unable to pump enough blood to the body
246
What % of deaths worldwide can be accredited to cancer?
13%
247
What % of deaths worldwide can be accredited to cancer?
13%
248
What causes retinal haemorrhage in Diabetic patients ?
Hyaline arteriosclerosis
Thickening of basement membrane in retinal blood vessels
