Clinical Sciences Flashcards
1
Q
Type I hypersensitivity reaction
Anaphylaxis
A
Antigen reacts with IgE to bind to Mast cells
Anaphylaxis, atopy
2
Q
Type II hypersensitivity reaction
Cell bound
A
IgG or IgM binds to antigen on cell surface
e.g. • Autoimmune haemolytic anaemia • ITP • Goodpasture's syndrome • Pernicious anaemia • Acute haemolytic transfusion reactions • Rheumatic fever • Pemphigus vulgaris / bullous pemphigoid
3
Q
Type III Immune Complex
A
Free antigen and antibody
Free antigen and antibody (IgG, IgA) combine • Serum sickness
• Systemic lupus erythematosus
• Post-streptococcal glomerulonephritis
• Extrinsic allergic alveolitis (especially acute phase)
4
Q
Type IV
Delayed hypersensitivity
A
T-cell mediated • Tuberculosis / tuberculin skin reaction
• Graft versus host disease
• Allergic contact dermatitis
• Scabies
• Extrinsic allergic alveolitis (especially chronic phase)
• Multiple sclerosis
• Guillain-Barre syndrome
5
Q
Type V hypersensitivity reaction
A
Antibodies that recognise and bind to the cell surface receptors.
This either stimulating them or blocking ligand binding • Graves’ disease
• Myasthenia gravis
6
Q
Causes of acute tubular necrosis
Ischaemia
A
shock
sepsis
7
Q
Causes of acute tubular necrosis
Nephrotoxins
A
aminoglycosides
myoglobin secondary to rhabdomyolysis
radiocontrast agents
lead
8
Q
Features of acute tubular necrosis
A
features of AKI: raised urea, creatinine, potassium
muddy brown casts in the urine
9
Q
Histology of Acute tubular necrosis
A
tubular epithelium necrosis: loss of nuclei and detachment of tubular cells from the basement membrane
dilatation of the tubules may occur
necrotic cells obstruct the tubule lumen
10
Q
phases of acute tubular necrosis
A
oliguric phase
polyuric phase
recovery phase
11
Q
Posterior half of the skull (cap)
A
C2
12
Q
High turtleneck shirt
A
C3
13
Q
Low-collar shirt
A
C4
14
Q
Ventral axial line of upper limb
A
C5
15
Q
Thumb + index finger
A
C6
16
Q
Middle finger + palm of hand
A
C7
17
Q
Ring + little finger
A
C8
18
Q
Nipples
A
T4
19
Q
Inframammary fold
A
T5
20
Q
Xiphoid process
A
T6
21
Q
Umbilicus
A
T 10
22
Q
Inguinal ligament
A
L1
23
Q
Knee caps
A
L4 ‘down on all 4s’
24
Q
Big toe, dorsum of foot (except lateral aspect)
A
L5
25
Lateral foot, small toe
S1
26
Genitalia
S2, 3
27
Metabolic acidosis
```
vomiting / aspiration (e.g. peptic ulcer leading to pyloric stenos, nasogastric suction)
diuretics
liquorice, carbenoxolone
hypokalaemia
primary hyperaldosteronism
Cushing's syndrome
Bartter's syndrome
```
28
Mechanism of Metabolic acidosis
```
activation of renin-angiotensin II-aldosterone (RAA) system is a key factor
aldosterone causes reabsorption of Na+ in exchange for H+ in the distal convoluted tubule
ECF depletion (vomiting, diuretics) → Na+ and Cl- loss → activation of RAA system → raised aldosterone levels
in hypokalaemia, K+ shift from cells → ECF, alkalosis is caused by shift of H+ into cells to maintain neutrality
```
29
Antibiotics for breast feeding mothers
penicillins, cephalosporins, trimethoprim
30
Safe endocrine drugs for breast feeding mothers
glucocorticoids (avoid high doses), levothyroxine*
31
Safe epilepsy drugs for breast feeding mothers
sodium valproate, carbamazepine
32
Safe asthma drugs for breast feeding mothers
salbutamol, theophyllines
33
Safe psychiatric drugs for breast feeding mothers
tricyclic antidepressants, antipsychotics**
34
Safe antihypertensive drugs for breast feeding mothers
beta-blockers, hydralazine
35
Safe anticoagulants in breast feeding mothers
warfarin, heparin
36
Antibiotics to avoid in breast feeding mothers
ciprofloxacin, tetracycline, chloramphenicol, sulphonamides
37
Psychiatric medications to avoid in breast feeding mothers
avoid in breast feeding mothers
38
Other drugs to avoid in breast feeding mothers
```
aspirin
carbimazole
methotrexate
sulfonylureas
cytotoxic drugs
amiodarone
```
39
Amino glycosides
Antibiotics ending in mycin e.g. Gentamicin, streptomycin, neomycin
40
Cell Cycle
G0
'resting' phase
| quiescent cells such as hepatocytes and more permanently resting cells such as neurons
41
Cell Cycle
G1
Gap 1, cells increase in size
determines length of cell cycle
under influence of p53
Cyclin D / CDK4, Cyclin D / CDK6 and Cyclin E / CDK2: regulates transition from G1 to S phase
42
Cell Cycle
G2
Gap 2, cells continue to increase in size
| Cyclin B / CDK1: regulates transition from G2 to M phase
43
Cell Cycle
S
Synthesis of DNA, RNA and histone
centrosome duplication
Cyclin A / CDK2: active in S phase
44
Cell cycle
M
Mitosis - cell division
| the shortest phase of the cell cycle
45
Clinical features of Down's syndrome
face: upslanting palpebral fissures, epicanthic folds, Brushfield spots in iris, protruding tongue, small low-set ears, round/flat face
flat occiput
single palmar crease, pronounced 'sandal gap' between big and first toe
hypotonia
congenital heart defects (40-50%, see below)
duodenal atresia
Hirschsprung's disease
46
Cardiac features of Down's syndrome
```
multiple cardiac problems may be present
endocardial cushion defect (most common, 40%, also known as atrioventricular septal canal defects)
ventricular septal defect (c. 30%)
secundum atrial septal defect (c. 10%)
tetralogy of Fallot (c. 5%)
isolated patent ductus arteriosus (c. 5%
```
47
Late effects of Down's syndrome
```
subfertility: males are almost always infertile due to impaired spermatogenesis. Females are usually subfertile, and have an increased incidence of problems with pregnancy and labour
learning difficulties
short stature
repeated respiratory infections (+hearing impairment from glue ear)
acute lymphoblastic leukaemia
hypothyroidism
Alzheimer's disease
atlantoaxial instability
```
48
Conditions associated with thiamine deficiency
Wernicke's encephalopathy: nystagmus, ophthalmoplegia and ataxia
Korsakoff's syndrome: amnesia, confabulation
dry beriberi: peripheral neuropathy
wet beriberi: dilated cardiomyopathy
49
Reactions that thiamine pyrophosphate is used in
pyruvate dehydrogenase complex
pyruvate decarboxylase in ethanol fermentation
alpha-ketoglutarate dehydrogenase complex
branched-chain amino acid dehydrogenase complex
2-hydroxyphytanoyl-CoA lyase
transketolase
50
Patau syndrome
Trisomy 13
Microcephalic, small eyes
Cleft lip/palate
Polydactyly
Scalp lesions
51
Edward's syndrome
Trisomy 18
Micrognathia
Low-set ears
Rocker bottom feet
Overlapping of fingers
52
Fragile X
```
Learning difficulties
Macrocephaly
Long face
Large ears
Macro-orchidism
```
53
Noonan's syndrome
Webbed neck
Pectus excavatum
Short stature
Pulmonary stenosis
54
Pierre-Robin syndrome
Micrognathia
Posterior displacement of the tongue (may result in upper airway obstruction)
Cleft palate
55
Prader-Willi syndrome
Hypotonia
Hypogonadism
Obesity
56
William's syndrome
```
Short stature
Learning difficulties
Friendly, extrovert personality
Transient neonatal hypercalcaemia
Supravalvular aortic stenosis
```
57
Cri du chat
| chromosome 5p deletion syndrome
Characteristic cry (hence the name) due to larynx and neurological problems
Feeding difficulties and poor weight gain
Learning difficulties
Microcephaly and micrognathism
Hypertelorism
58
Sensitivity
TP/ TP +FN Proportion of patients with the condition who have a positive test result
59
Specificity
TN/TN +TP Proportion of patients without the condition who have a negative test result
60
Positive predictive value
TP / (TP + FP) The chance that the patient has the condition if the diagnostic test is positive
61
Negative predictive value
TN / (TN + FN) The chance that the patient does not have the condition if the diagnostic test is negative
62
Arachidonic acid products
PGI 2
decreased platelet aggregation
vasodilation
decreased uterine tone
63
Arachidonic acid products
| TXA2
vasoconstriction
| increased platelet aggregation
64
Leukotrienes
LTB4: B4 (before) leukocytes comes LTB4
| the rest A, C, D & E constrict the lungs
65
Endoperoxides
THROMBOxane think THROMBOSIS: platelets aggregated and vasoconstriction. Prostacyclin is the opposite
66
Phospholipid ----->
| Phospholipase A2
Arachidonic acid
67
Arachidonic acid ---->
| Lipoxegenase
HPETEs
68
HPETEs
LTB4 (increase chemotaxis)
Leukotrienes (LA4, LC4, LD4, LE4 ) increase bronchoconstriction
69
Arachidonic acid ----->
| COX-1, COX-2
Endoperoxides - prostacyclin, prostaglandin, thromboxane
70
Prostacyclin
| PGl 2
Vasodilation
Decreased platelet aggregation
Decreased uterine tone
71
Prostaglandin
| PGE 2
Increased: pain, uterine tone, temp, gastric mucus
Decreased: gastric acid
Varying effects for smooth muscles and airways
72
Thromboxane
TXA2
Vasoconstriction
| Increased platelet aggregation
73
Rough endoplasmic reticulum
translation and folding of new proteins
manufacture of lysosomal enzymes
site of N-linked glycosylation
examples of cells with extensive RER include pancreatic cells, goblet cells, plasma cells
74
Smooth endoplasmic reticulum
steroid, lipid synthesis
| examples of cells with extensive SER include those of the adrenal cortex, hepatocytes, testes, ovaries
75
Golgi apparatus
Modifies, sorts, and packages these molecules that are destined for cell secretion
The addition of mannose-6-phosphate to proteins designates transport to lysosome
76
Mitochondrion
Aerobic respiration. Contains mitochondrial genome as circular DNA
77
Nucleus
DNA maintenance
RNA transcription
RNA splicing
the process that removes the intervening, non-coding sequences of genes (introns) from pre-mRNA and joins the protein-coding sequences (exons)
78
Lysosome
Breakdown of large molecules such as proteins and polysaccharides
79
Nucelous
Ribosome production
80
Ribosome
Translation of RNA into proteins
81
Peroxisome
Catabolism of very long chain fatty acids and amino acids
| Results in the formation of hydrogen peroxide
82
Proteasome
Along with the lysosome pathway involved in degradation of protein molecules that have been tagged with ubiquitin
83
Hawthorne effect
the alteration of behaviour by the subjects of a study due to their awareness of being observed.
84
Linear regression
linear regression may be used to predict how much one variable changes when a second variable is changed. A regression equation may be formed, y = a + bx, where
y = the variable being calculated
a = the intercept value, when x = 0
b = the slope of the line or regression coefficient. Simply put, how much y changes for a given change in x
x = the second variable
85
Correlation coefficient
This indicates how closely the points lie to a line drawn through the plotted data. In parametric data this is called Pearson's correlation coefficient and can take any value between -1 to +1.
86
Ligand-gated ion channel receptor
generally mediate fast responses
| e.g. nicotinic acetylcholine, GABA-A & GABA-C, glutamate receptors
87
Tyrosine kinase receptor
generally mediate fast responses
| e.g. nicotinic acetylcholine, GABA-A & GABA-C, glutamate receptors
88
Guanylate cyclase receptors
contain intrinsic enzyme activity
| e.g. atrial natriuretic factor, brain natriuretic peptide
89
G protein coupled receptors
generally mediate slow transmission and affect metabolic processes
activated by a wide variety of extracellular signals e.g. Peptide hormones, biogenic amines (e.g. adrenaline), lipophilic hormones, light
7-helix membrane-spanning domains
consist of 3 main subunits: alpha, beta and gamma
the alpha subunit is linked to GDP.Ligand binding causes conformational changes to receptor, GDP is phosphorylated to GTP,and the alpha subunit is activated
G proteins are named according to the alpha subunit (Gs, Gi, Gq)
90
Mechanism of Gs receptor
Stimulates adenylate cyclase → increases cAMP → activates protein kinase A
91
Examples of Gs protein coupled receptor
* Beta-1 receptors (epinephrine, norepinephrine, dobutamine)
* Beta-2 receptors (epinephrine, salbuterol)
* H2 receptors (histamine)
* D1 receptors (dopamine)
* V2 receptors (vasopressin)
* Receptors for ACTH, LH, FSH, glucagon, PTH, calcitonin, prostaglandins
92
Mechanism of Gi protein coupled receptor
Inhibits adenylate cyclase → decreases cAMP → inhibits protein kinase A
93
Examples of Gi protein coupled receptor
* M2 receptors (acetylcholine)
* Alpha-2 receptors (epinephrine, norephinephrine)
* D2 receptors (dopamine)
* GABA-B receptor
94
Mechanism of Gq protein coupled receptor
Activates phospholipase C → splits PIP2 to IP3 & DAG → activates protein kinase C
95
Examples of Gq protein coupled receptors
* Alpha-1 receptors (epinephrine, norepinephrine)
* H1 receptors (histamine)
* V1 receptors (vasopressin)
* M1, M3 receptors (acetylcholine)
96
Trendelenburg sign positive
injury to superior gluteal nerve
97
Characteristic features of congenital rubella
Sensorineural deafness
Congenital cataracts
Congenital heart disease (e.g. patent ductus arteriosus)
Glaucoma
98
Other features of congenital rubella
```
Growth retardation
Hepatosplenomegaly
Purpuric skin lesions
'Salt and pepper' chorioretinitis
Microphthalmia
Cerebral palsy
```
99
Characteristic features of congenital toxoplasmosis
Cerebral calcification
Chorioretinitis
Hydrocephalus
100
Other features of congenital toxoplasmosis
Anaemia
Hepatosplenomegaly
Cerebral palsy
101
Characteristic features of congenital cytomegalovirus
Growth retardation
| Purpuric skin lesions
102
Other features of congenital cytomegalovirus
```
Sensorineural deafness
Encephalitis/seizures
Pneumonitis
Hepatosplenomegaly
Anaemia
Jaundice
Cerebral palsy
```
103
ELISA
Enzyme-linked immunosorbent assay (ELISA)
a type of biochemical assay used to detect antigens and antibodies
a colour changing enzyme is attached to the antibody if looking for an antigen and to an antigen if looking for an antibody
the sample therefore changes colour if the antigen or antibody is detected
an example includes the initial HIV test
104
Southern blotting
Detects DNA
105
Northern blotting
Detects RNA
106
Western blotting
Detects proteins
Uses gel electrophoresis to separate native proteins by 3-D structure
Examples include the confirmatory HIV test
107
Type 1 error
the null hypothesis is rejected when it is true - i.e. Showing a difference between two groups when it doesn't exist, a false positive. This is determined against a preset significance level (termed alpha). As the significance level is determined in advance the chance of making a type I error is not affected by sample size. It is however increased if the number of end-points are increased. For example if a study has 20 end-points it is likely one of these will be reached, just by chance
108
Type 2 error
the null hypothesis is accepted when it is false - i.e. Failing to spot a difference when one really exists, a false negative. The probability of making a type II error is termed beta. It is determined by both sample size and alph
109
number needed to treat
1/ absolute risk reduction
110
McCune-Albright syndrome
precocious puberty
cafe-au-lait spots
polyostotic fibrous dysplasia
short stature
111
Mann-Whitney U test
compares ordinal, interval, or ratio scales of unpaired data
| non parametric
112
Chi squared test
used to compare proportions or percentages e.g. compares the percentage of patients who improved following two different interventions
non-parametric
113
Wilson's signed rank-test
compares two sets of observations on a single sample, e.g. a 'before' and 'after' test on the same population following an intervention
non-parametric
114
Spearman, Kendall rank
correlation- non parametric
115
Long thoracic nerve injury
winging scapula (serratus anterior)
116
Femoral nerve injury
Motor- Knee extension, thigh flexion
Sensory - Anterior and medial aspect of the thigh and lower leg
Mechanism of action- Hip and pelvic fractures
Stab/gunshot wounds
117
Zona glomerulosa
(on outside): mineralocorticoids, mainly aldosterone
118
Zona fasciulata
(middle): glucocorticoids, mainly cortisol
119
zona reticularis
(on inside): androgens, mainly dehydroepiandrosterone (DHEA)
120
Renin
an enzyme that is released by the renal juxtaglomerular cells in response to reduced renal perfusion
other factors that stimulate renin secretion include hyponatraemia, sympathetic nerve stimulation
hydrolyses angiotensinogen to form angiotensin I
121
Angiotensin II
angiotensin-converting enzyme (ACE) in the lungs converts angiotensin I → angiotensin II
angiotensin II has a wide variety of actions:
causes vasoconstriction of vascular smooth muscle leading to raised blood pressure and vasoconstriction of efferent arteriole of the glomerulus → increased filtration fraction (FF) to preserve GFR. Remember that FF = GFR / renal plasma flow
stimulates thirst (via the hypothalamus)
stimulates aldosterone and ADH release
increases proximal tubule Na+/H+ activity
122
Aldosterone
released by the zona glomerulosa in response to raised angiotensin II, potassium, and ACTH levels
causes retention of Na+ in exchange for K+/H+ in distal tubule
123
C1 inhibitor (C1-INH) protein deficiency
causes hereditary angioedema
C1-INH is a multifunctional serine protease inhibitor
probable mechanism is uncontrolled release of bradykinin resulting in oedema of tissues
124
C1q, C1rs, C2, C4 deficiency (classical pathway components)
predisposes to immune complex disease
| e.g. SLE, Henoch-Schonlein Purpura
125
C3 deficiency
causes recurrent bacterial infections
126
C5 deficiency
predisposes to Leiner disease
| recurrent diarrhoea, wasting and seborrhoeic dermatitis
127
C5-9 deficiency
encodes the membrane attack complex (MAC)
| particularly prone to Neisseria meningitidis infection
128
X-linked dominant condition's
Rett syndrome
Alport syndrome
Vitamin D resistant rickets
129
X-linked recessive conditions
```
Androgen insensitivity syndrome
Becker muscular dystrophy
Colour blindness
Duchenne muscular dystrophy
Fabry's disease
G6PD deficiency
Haemophilia A,B
Hunter's disease
Lesch-Nyhan syndrome
Nephrogenic diabetes insipidus
Ocular albinism
Retinitis pigmentosa
Wiskott-Aldrich syndrome
```
130
Phase 0 of the cardiac cycle
Rapid depolarisation
Rapid sodium influx
These channels automatically deactivate after a few ms
131
Phase 1 of the cardiac cycle
Early repolarisation
| Efflux of potassium
132
Phase 2 of the cardiac cycle
Plateau
| Slow influx of calcium
133
Phase 3 of the cardiac cycle
Final repolarisation
| Efflux of potassium
134
Phase 4 of the cardiac cycle
Restoration of ionic concentrations
Resting potential is restored by Na+/K+ ATPase
There is slow entry of Na+ into the cell decreasing the potential difference until the threshold potential is reached, triggering a new action potential
135
standard error of the mean
standard deviation/ square root (n)
136
Hyponatraemia
Sodium depletion, renal loss (patient often hypovolaemic)
Urinary sodium >20 mmol
diuretics: thiazides, loop diuretics
Addison's disease
diuretic stage of renal failure
137
Hyponatraemia
Patient often euvolaemic
Urinary sodium >20mmol
SIADH (urine osmolality > 500 mmol/kg)
| hypothyroidism
138
Hyponatraemia
Urinary sodium < 20 mmol/l
Sodium depletion, extra-renal loss
diarrhoea, vomiting, sweating
| burns, adenoma of rectum
139
Hyponatraemia
Urinary sodium < 20 mmol/l
Water excess (patient often hypervolaemic and oedematous)
secondary hyperaldosteronism: heart failure, liver cirrhosis
nephrotic syndrome
IV dextrose
psychogenic polydipsia
140
Mechanism of metabolic acidosis
```
activation of renin-angiotensin II-aldosterone (RAA) system is a key factor
aldosterone causes reabsorption of Na+ in exchange for H+ in the distal convoluted tubule
ECF depletion (vomiting, diuretics) → Na+ and Cl- loss → activation of RAA system → raised aldosterone levels
in hypokalaemia, K+ shift from cells → ECF, alkalosis is caused by shift of H+ into cells to maintain neutrality
```
141
what is carbenoxolone
Carbenoxolone (CBX) is a glycyrrhetinic acid derivative with a steroid-like structure, similar to substances found in the root of the licorice plant. Carbenoxolone is used for the treatment of peptic, esophageal and oral ulceration and inflammation.
142
what is bartter's syndrome
Bartter syndrome is a general term for a group of rare genetic disorders in which there are specific defects in kidney function. These defects impair the kidney's ability to reabsorb salt and cause imbalances in various electrolyte and fluid concentrations in the body.
Causes metabolic acidosis
143
Li-Fraumeni syndrome
an inherited familial predisposition to a wide range of certain, often rare, cancers. This is due to a change (mutation) in a tumor suppressor gene known as TP53.
144
Oncogenes
```
c-MYC
ABL
BCL-2
RET
erb-B2 (HER2/neu)
RAS
n-MYC
```
145
Tumour suppressor genes
```
BRCA1
BRCA2
WT1
APC
NF1
Rb
multiple tumor suppressor 1 (MTS-1, p16)
p53
```
146
What is homocystinuria
Homocystinuria is a rare autosomal recessive disease caused by a deficiency of cystathionine beta synthase. This results in severe elevations in plasma and urine homocysteine concentrations.
147
features of homocystinuria
often patients have fine, fair hair
musculoskeletal
Marfanoid body habitus: arachnodactyly etc
osteoporosis
kyphosis
neurological: may have learning difficulties, seizures
ocular
downwards (inferonasal) dislocation of lens
severe myopia
increased risk of arterial and venous thromboembolism
also malar flush, livedo reticularis
148
Investigations of homocystinuria
increased homocysteine levels in serum and urine
cyanide-nitroprusside test: also positive in cystinuria
Treatment is vitamin B6 (pyridoxine) supplements.
149
Acute intermittent porphyria
Autosomal dominant
are metabolic disorder that is characterized by partial deficiency of the enzyme hydroxymethylbilane synthase (also known as porphobilinogen deaminase). This enzyme deficiency can result in the accumulation of porphyrin precursors in the body.
150
Pattern of inheritance
| Retinoblastoma
Autosomal dominant
151
Pattern of inheritance
| Osteogenesis Imperfecta
Autosomal dominant
152
Pattern of Inheritance
| Malignant hyperthermia
Autosomal dominant
153
what is correlation coefficient
a measure of strength of the linear relationship between two variables
154
A boy presents with arm problems after falling from a tree, during which he caught a branch to save himself. On examination he has a claw hand with a hyperextended wrist - lower trunk of the brachial plexus
Which nerve is damaged
Long thoracic nerve (C8, T1)
155
cohort study outcome
The usual outcome measure is the relative risk
156
cross sectional study outcome
Collects data to measure disease prevalence
157
Limitations of randomised control
Practical or ethical problems may limit use
158
outcome of case control
The usual outcome measure is the odds ratio
159
```
zona glomerulosa (on outside)
RAAS
```
mineralocorticoids, mainly aldosterone
160
zona fasciculata (middle):
glucocorticoids, mainly cortisol
161
zona reticularis (on inside)
androgens, mainly dehydroepiandrosterone (DHEA)
162
what is Renin
an enzyme that is released by the renal juxtaglomerular cells in response to reduced renal perfusion
other factors that stimulate renin secretion include hyponatraemia, sympathetic nerve stimulation
hydrolyses angiotensinogen to form angiotensin I
163
What is aldosterone?
angiotensin-converting enzyme (ACE) in the lungs converts angiotensin I → angiotensin II
164
Role of angiotensin II
```
causes vasoconstriction of vascular smooth muscle leading to raised blood pressure and vasoconstriction of efferent arteriole of the glomerulus → increased filtration fraction (FF) to preserve GFR. Remember that FF = GFR / renal plasma flow
stimulates thirst (via the hypothalamus)
stimulates aldosterone and ADH release
increases proximal tubule Na+/H+ activity
```
165
what is aldosterone
released by the zona glomerulosa in response to raised angiotensin II, potassium, and ACTH levels
causes retention of Na+ in exchange for K+/H+ in distal tubule
166
superior gluteal nerve injury
Hip abduction
Causes: Misplaced intramuscular injection, Hip surgery, Pelvic fracture, Posterior hip dislocation
Injury results in a positive Trendelenburg sign
167
Femoral nerve injury
Motor signs: Knee extension, thigh flexion
Sensory signs: Anterior and medial aspect of the thigh and lower leg
Causes: Hip and pelvic fractures
Stab/gunshot wounds
168
Obturator nerve injury
Motor: Thigh adduction
Sensory: Medial thigh
Cause: Anterior hip dislocation
169
Lateral cutaneous nerve of the thigh
Motor: None
Sensory: Lateral and posterior surfaces of the thigh
Cause: Compression of the nerve near the ASIS → meralgia paraesthetica, a condition characterised by pain, tingling and numbness in the distribution of the lateral cutaneous nerve
170
Tibial nerve injury
Motor:Foot plantar flexion and inversion
Sensory: Sole of foot
Causes: Not commonly injured as deep and well protected.
Popliteral lacerations, posterior knee dislocation
171
Common peroneal nerve injury
Motor: Foot dorsiflexion and eversion, Extensor hallucis longus
Sensory: Dorsum of the foot and the lower lateral part of the leg
Cause: Injury often occurs at the neck of the fibula, Tightly applied lower limb plaster cast, Injury causes foot drop
172
Inferior gluteal nerve injury
Motor: Hip extension and lateral rotation
Sensory: None
Cause: Generally injured in association with the sciatic nerve Injury results in difficulty rising from seated position. Can't jump, can't climb stairs
173
odds ratio
Odds are a ratio of the number of people who incur a particular outcome to the number of people who do not incur the outcome. The odds ratio may be defined as the ratio of the odds of a particular outcome with experimental treatment and that of control.
174
Probabilty
In contrast, probability is the fraction of times you'd expect to see an event in many trials.
175
what receptor does prolactin act on?
non- receptor tyrosine kinase
176
PGI2
decreased platelet aggregation
vasodilation
decreased uterine tone
177
PGE2
```
decreased gastric acid secretion
increased pain
increased uterine tone
increased gastric mucus secretion
increased temperature
```
178
Cranial nerve lesions
| CN IX
hypersensitive carotid sinus reflex
179
Cranial nerve lesions CN X
uvula deviated away from the side of lesion
180
Cranial nerve lesions CN VII
loss of corneal reflex
| flaccid paralysis of upper + lower face
181
what is McCune-Albright syndrome
McCune-Albright syndrome is not inherited, it is due to a random, somatic mutation in the GNAS gene.
```
Features
precocious puberty
cafe-au-lait spots
polyostotic fibrous dysplasia
short stature
```
182
stereotypical history of McCune Albright syndrome
a 6-year-old girl is investigated for precocious puberty. On examination she is noted to have cafe-au-lait spots predominately on one side of her body and a skull deformity
183
stereotypical history of Lesch-Nyhan syndrome
a boy with a history of learning difficulties and self-mutilation presents with recurrent episodes of gout
184
HLA-A3
haemochromatosis
185
HLA B51
Behcet's
186
HLA B27
ankylosing spondylitis
reactive arthritis
acute anterior uveitis
187
HLA-DQ2/DQ8
coeliac disease
188
HLA DR2
narcolepsy
| Goodpasture's
189
HLA DR3
dermatitis herpetiformis
Sjogren's syndrome
primary biliary cirrhosis
190
HLA DR4
Type 1 diabetes mellitus* (also DR3)
| rheumatoid arthritis - in particular the DRB1 gene (DRB1*04:01 and DRB1*04:04 hence the association with DR4)
191
positive predictive value
The chance that the patient has the condition if the diagnostic test is positive
192
'How much the odds of the disease increase when a test is positive' is what?
likelihood ratio for a positive test result
193
formula for specificity
TN / (TN + FP)
194
formula for sensitivity
TP / (TP + FN )
195
formula for likelihood ratio for a negative test result
(1 - sensitivity) / specificity
196
X-linked dominant conditions
vitamin D resistant rickets
Alport's syndrome
Rett syndrome
197
Trinucleotide repeat disorders
| CGG
Fragile X
198
Trinucleotide repeat disorders
| CAG
Huntingtons
199
Trinucleotide repeat disorders
| CTG
myotonic dystrophy
200
Trinucleotide repeat disorder
| GAA
Freidreich's ataxia
201
Goal of a Phase I clinical trial
Determines pharmacokinetics and pharmacodynamics and side-effects prior to larger studies
202
Goal of a Phase II clinical trial
Assess efficacy + dosage Involves small number of patients affected by particular disease
May be subdivided into
IIa - assesses optimal dosing
IIb - assesses efficacy
203
Goal of a Phase III clinical trial
Assess effectiveness Typically involves 100-1000's of people, often as part of a randomised controlled trial, comparing new treatment with established treatments
204
Goal of a Phase IV clinical trial
Postmarketing surveillance Monitors for long-term effectiveness and side-effects
205
Where is leptin produced
It is produced by adipose tissue and acts on satiety centres in the hypothalamus and decreases appetite. More adipose tissue (e.g. in obesity) results in high leptin levels. Leptin stimulates the release of melanocyte-stimulating hormone (MSH) and corticotrophin-releasing hormone (CRH). Low levels of leptin stimulates the release of neuropeptide Y (NPY)
206
What is Ghrelin
Where as leptin induces satiety, ghrelin stimulates hunger. It is produced mainly by the P/D1 cells lining the fundus of the stomach and epsilon cells of the pancreas. Ghrelin levels increase before meals and decrease after meals
207
Inheritance pattern for antithrombin III deficiency
Autosomal dominant
208
Types of data: interval
A measurement where the difference between two values is meaningful, such that equal differences between values correspond to real differences between the quantities that the scale measures (for example temperature)
209
Types of data: Ordinal
Observed values can be put into set categories which themselves can be ordered (for example NYHA classification of heart failure symptoms)
210
Types of data: Nominal
Observed values can be put into set categories which have no particular order or hierarchy. You can count but not order or measure nominal data (for example birthplace)
211
Types of Data: Discrete
Observed values are confined to a certain values, usually a finite number of whole numbers (for example the number of asthma exacerbations in a year)
212
Types of data: Continuous
Data can take any value with certain range (for example weight)
213
Types of Data: Binominal
Data may take one of two values (for example gender)
214
Define confidence interval
a range of values for a variable of interest constructed so that this range has a specified probability of including the true value of the variable. The specified probability is called the confidence level, and the end points of the confidence interval are called the confidence limits*
215
Absolute risk reduction =
1/ number needed to treat
| The difference between the event rate in the intervention group and that in the control group
216
Pattern of inheritance: occular albinism
X-linked recessive
217
statistical definition of power
The probability of detecting a statistically significant difference
218
statistical definition of p value
Is the probability of obtaining a result by chance at least as extreme as the one that was actually observed, assuming that the null hypothesis is true
219
Inheritance of hereditary spherocytosis
Autosomal dominant
220
statistical definitions: significance
The probability of getting the results if the null hypothesis is true
221
statistical definition: power
The probability of (correctly) rejecting the null hypothesis when it is false
222
inheritance pattern: Romano-ward syndrome
Autosomal dominant
223
Drugs to avoid in breast feeding
```
antibiotics: ciprofloxacin, tetracycline, chloramphenicol, sulphonamides
psychiatric drugs: lithium, benzodiazepines
aspirin
carbimazole
methotrexate
sulfonylureas
cytotoxic drugs
amiodarone
```
224
Drugs that are considered safe in breast feeding
antibiotics: penicillins, cephalosporins, trimethoprim
endocrine: glucocorticoids (avoid high doses), levothyroxine*
epilepsy: sodium valproate, carbamazepine
asthma: salbutamol, theophyllines
psychiatric drugs: tricyclic antidepressants, antipsychotics**
hypertension: beta-blockers, hydralazine
anticoagulants: warfarin, heparin
digoxin
225
internal auditory meatus
CN VII
| CN VIII
226
Inheritance of myotonic dystrophy
Autosomal Dominant
227
Congenital cytomegalovirus
growth retardation, purpuric skin lesions, sensorineural deafness and seizures
228
function of a proteosome
Degradation of protein molecules that have been tagged with ubiquitin
229
Mutations leading to Neuroblastoma
n-MYC
230
Wilcoxon matched-pairs
Non-parametric test that compares two sets of observations on a single sample
231
Chi-Squared Test
Non-parametric test used to compare proportions or percentages
232
Stereotypical history of Turner's syndrome
a baby is reviewed shortly after birth as a fetal ultrasound showed a cystic hygroma. On examination the baby has swollen hands and feet and echocardiography shows a bicuspid aortic valve
233
Mann-Whitney test
Non-parametric test of unpaired data
234
Pattern of inheritance: homocystinuria
Autosomal recessive
235
likelihood ratio for a positive test result
Sensitivity / (1 - specificity)
236
Underlying aetiology of alkaptonuria
Deficiency of homogentisic dioxygenase
237
Type II error
The null hypothesis is accepted when it is false
238
mode of inheritance of lipid storage disease: Tay-Sach's, Gaucher, Niemann-Pick?
Autosomal recessive
239
mode of inheritance of Peutz-Jeghers syndrome
Autosomal recessive
240
Stereotypical history of WIlliam's syndrome
a boy with learning difficulties is noted to be extremely friendly and extroverted. He has short for his age and has supravalvular aortic stenosis
241
Gaussian distribution
Normal (Gaussian) distributions: mean = median = mode
242
Negatively skewed data
mean < median < mode
243
Positively skewed data
mean > median > mode
244
Wilcoxon signed-rank test
compares two sets of observations on a single sample, e.g. a 'before' and 'after' test on the same population following an intervention
245
Paired T-test
Should only be used on data with a normal distribution
246
McNemar's test
Classically used on paired nominal data. Classically this test can be used to compare the sensitivity and specificity of 2 diagnostic tests on a matched sample.
247
Secondary messanger stimulated by nitric oxide
cGMP
248
Prader-Willisyndrome
Paternal = Prader-will
Maternal = angelMan
caused by: microdeletion of paternal 15q11-13 (70% of cases)
maternal uniparental disomy of chromosome 15
249
Chronic emphysema
leads to increased pulmonary compliance
250
peroxisomes
intracellular organelle responsible for breaking down long chain fatty acids
251
Prometaphase
Nuclear membrane breaks down allowing the microtubules to attach to the chromosomes
252
Metaphase
Chromosomes aligned at middle of cell
253
Prophase
Chromatin in the nucleus condenses
254
Anaphase
The paired chromosomes separate at the kinetochores and move to opposite sides of the cell
255
Telophase
Chromatids arrive at opposite poles of cell
256
Cytokinaesis
Actin-myosin complex in the centre of the cell contacts resulting in it being 'pinched' into two daughter cells
257
Cytokinaesis
Actin-myosin complex in the centre of the cell contacts resulting in it being 'pinched' into two daughter cells
258
Coeliac HLA
HLA DQ2
259
Fabry disease
disorder of lysosomal storage and deficiency of alpha-galactosidase A. Common features of Fabry disease include acute pain episodes in the peripheries, angiokeratomas, hypohidrosis and corneal opacity. Organ involvement is also common and results in cardiovascular disease, myocardial infarction, strokes and progressive kidney disease. Fabry disease is inherited in an X-linked recessive fashion.
