QF 11 Flashcards
Parkinson’s arises specifically from degredation of which part of the brain? [1]
substantia nigra pars compacta (SNc)
What is a Rinne positive and negative test result? [1]
If the bone conduction through the mastoid process is heard louder than through the air, the patient is Rinne negative
Positive state indicates healthy state
[] Hz tuning fork is the most commonly clinically used tool to test for vibratory sensation
128 Hz tuning fork is the most commonly clinically used tool to test for vibratory sensation
In bone marrow aspiration, a needle is used to withdraw a sample of the fluid portion. In bone marrow biopsy, a needle is used to withdraw a sample of the solid portion.
Bone marrow aspirate or biopsy?
Aspirate
Bone marrow aspirate or biopsy?
Biopsy
Average lifespan of platelet? [1]
Platelet lifespan
8 to 14 days
Primary haemostasis (platelet number and function) is tested in lab using bleeding time. What is the range for normal bleeding time?
Normal bleeding time: 1-3 minutes
Where is VWF synthesised [2] and stored? [3]
Synthesised by
* Endothelial cells
* Megakaryocytes
Stored in
* Subendothelial matrix (immobilized state)
* Present in the soluble state in the plasma
* Alpha granules of the platelets
State two granule contents released from platelets and their roles during primary haemostasis [4]
ADP: Aggregation of platelets
Synthesis & release of thromboxane A2: Vasoconstriction
Fibrinogen binds to [] on adjacent platelets
Fibrinogen binds to GPIIb/IIIa on adjacent platelets
thrombin works by postive feedback due to continued activation from which factor? [1]
Va
Factor X works by postive feedback due to continued activation from which factor? [1]
Factor VIIIa
Which Factor does thrombin activate in the common pathway, which helps fibrin become crosslinked? [1]
Factor XIII
Describe a downregulator of coagulation cascade [1]
Thrombomodulin is a cofactor for thrombin that converts Thrombin from a procoagulant to an anticoagulant by stimulating activation of the anticoagulant serine protease protein C.
What are the 3 main anticoagulants of the body? [3]
antithrombin
protein c
protein s
What are the borders of the triangle of safety? [4]
Triangle of safety: Pec major, lat, 5th intercostal space, axilla
What volumes of blood are lost of classes I-IV of shock? [4]
Describe the characterstics of haemophilia [1]
People with Haemophilia (PWH) do not bleed faster but
bleed for a longer period of time.
This person has ?
haemophilia
What is inheritence of hameophilia? [1]
Hemophilia A and hemophilia B are inherited in an X-linked recessive pattern
What is inheritence pattern for VDW types? [3]
Type 1 and 2: Autosomal Dom
Type 3: Autosomal Rec
Describe how we differentiate between iron deficiency anaemia (IDA) from anaemia of
inflammation? [2]
How do you tell if a person has inflammation AND IDA the iron deficiency?
The most useful blood test is serum ferritin – it will be low in pure IDA and high in
anaemia of inflammation.
Serum transferrin receptor levels will be elevated in IDA and normal in anaemia
inflammation
The key caveat is that in a person with inflammation AND IDA the iron deficiency may be “masked” because ferritin is an acute phase reactant – in that case ferritin will be normal but in the low normal range.
Describe pathophysiology and characteristics of Hirschsprungs disease
Nerve cells are absent in myenteric plexus of rectum and distal bowel
Parasympathetic cells do not travel all the way to colon; can’t relax and move: obstruction of the bowel
Which population is Hirschprungs disease often found in? [1]
Down Syndrome
vomiting green fluid (bile), failing to pass meconiumwithin 48 hoursand a swollen belly could indicate? [1]
Hirschsprungs Disease
[] occurs when a remnant of the yolk sac (Vitelline duct) persists.
Meckel’s diverticulum occurs when a remnant of the yolk sac (Vitelline duct) persists.
Draw the tracts of the spinal cord
Describe the effects of Brown-Sequard Syndrome:
- at level of lesion [2]
- Below level of lesion [1]
- 1-2 levels velow [1]
Describe the key characteristics of anterior spinal cord syndrome [2]
Damage to the anterior portion of the spinal cord will cause bilateral disruption of the spinothalamic tracts, resulting in bilateral loss of pain and temperature sensation.
The corticospinal tracts are also likely to have been affected, resulting in bilateral spastic paralysis and UMN signs
This is ? [1]
name 3 causes [3]
Howell–Jolly body
Common causes include asplenia (post-splenectomy) or congenital absence of spleen (right atrial appendage isomerism). Spleens are also removed for therapeutic purposes in conditions like hereditary spherocytosis, trauma to the spleen, and autosplenectomy caused by sickle cell anemia.
Name an example of each type of hypersensitivity reaction
Type I – Allergic; Type II – Cytotoxic; Type III – Immune complex deposition; Type IV – Delayed.
After how many days do you get zygote, morula and blastocyst being produced? [3]
Day 1 produces the fertilised egg (zygote) and by late day 1 the zygote has reached 2 cell stage, early day 2 4 cell stage, early day 3 8 cell stage, and late day 3 16 cell stage on
day 4 the morula is formed and then the
blastocyst by day 5.
Explain mechanism of proliferation versus apoptosis in normal prostate vs BPE
Testosterone is converted to oestradiol in the stromal cells via the enzyme aromatase.
oestradiol then goes to the enzyme oestrogen receptor alpha and drives cell proliferation after it binds to in the stromal cells.
Oestradiol also goes into the epithelial cells and activate oestrogen receptor beta of the glands (in both the basal and luminal epithelial cells) and causes apoptosis
Testosterone can also enter directly into the basal epithelial cells converted to Dihydrotestosterone (DHT) by 5-alpha reductase in the epithelial cells. DHT can then pass into luminal epithelial, binds to androgen receptor and stops apoptosis
With BPE most of the oestradoil goes to the stomal cells and ERa and causes proliferation. Very little goes to ERbeta to cause apoptosis.
Due to increased Testosterone and therefore DHT: get more of androgen receptor, which drives luminal cells to hypetrophy.
Get proliferation of stromal cells and hypertrophy of epitheilial cells
Nucleus reticularis paragigantocellularis is a major afferent from which nuclei? [1]
Where does it go to? [1]
The nPGi is one of two major afferents of the locus coeruleus (LC), and sends collateral projections to the LC and to the nucleus of the solitary tract (NTS)
Draw the cycle of the PAG thing
Which anti-emetic is used for motion sickness & vestibular disturbances? [1]
Hycosine
Describe MoA of hycosine and state use [2]
Hycosine:
* M5 receptor antagonist; prevents Ach action in brainstem or vestibular nuclei
Name two drugs given for motion sickness [2]
Diphyenydramine / dramamine
Cyclizine
Describe the MoA of:
Diphyenydramine / dramamine [2]
Cyclizine [1]
Diphyenydramine / dramamine: H1 antagonist; M2 antagonist
Cyclizine; H1 antagonist
Which drug is used for gastroparesis (delayed gastric emptying)? [1]
Metclopramide
What is the MoA of Metclopramide? [2]
D2 receptor antagonist & 5HT4 agonist
Name a CB1 receptor agonist [1]
THC
What is the MoA of ondansetron and alosetron? [1]
What is the clinical use? [1]
5HT3 agonist; used for chemo and radiotherapy induced emesis
Name an atypical antiphyschotic used as an anti-emetic [1]
Olanzapine
What are the antigens and antibodies for different blood groups?
Which blood groups are the universal donor and recipients? [2]
Explain why [2]
O is therefore the universal donor as O blood cells have no antigens
AB is the universal recipient as it has no circulating AB antibodies
Which group has no antibodies
Group A
Group B
Group AB
Group O
Which group has no antibodies
Group A
Group B
Group AB
Group O
Which group has no antigens
Group A
Group B
Group AB
Group O
Which group has no antigens
Group A
Group B
Group AB
Group O
Describe the genotypes that make a person rhesus D postive [2] or negative [1]
The D status is the most immunogenic and therefore what determines the +ve/-ve state:
DD or Dd genotype -> express the immunogenic D antigen = rhesus positive
dd genotype -> no expression of the D antigen = rhesus negative
Describe pathophysiology of Haemolytic Disease of the Newborn
Maternal anti-D is which immunoglobulin? [1]
Maternal anti-D = IgG is rapidly produced on repeat exposure to Rh D antigen following sensitisation in the first pregnancy.
IgG crosses the placenta and binds to the fetal D antigen causing fetal RBC haemolysis
How do you prevent Haemolytic Disease of the Newborn? [1]
Anti-D immunoglobulin: neutralises Rh+ve antigens
What causes acute haemolytic reaction? [1]
What happens as a result? [1]
ABO-incompatible blood e.g. secondary to human error
Causes massive intravascular haemolysis mediated through IgM
Which Ig causes acute haemolytic reaction?
IgM
What causes non-haemolytic febrile reaction? [1]
Thought to be caused by HLA antibodies: Antibodies react with white cell fragments in the blood product and cytokines that have leaked from the blood cell during storage
Describe what causes blood anaphylaxis
Occurs when patients with IgA deficiency who have anti-IgA antibodies are given blood with IgA
Describe what is transfusion-associated circulatory overload (TACO) [1]
Fluid overload: Caused by excessive rate of transfusion in pre-existing heart failure
What is Transfusion-related acute lung injury (TRALI)?
Non-cardiogenic pulmonary oedema
Thought to be secondary to neutrophils activation
Degranulation of WBCs increases vascular permeability leading to inflammation and oedema
The heart starts to beat on day …[ ]
Starts to beat on day 22
This shows? [1]
ToF
The PDA closes how long after birth? [1]
PDA stays open approx. 24-48hrs fully closes within week
How can you treat Persistent pulmonary hypertension of the new-born? [3]
Inhaled NO
Prostaglandin: PGE1 or PGI2
Others, sildenafil, milrinone
Describe pathophysiology of Persistent pulmonary hypertension of the new-born
Characterized by elevated pulmonary vascular resistance resulting in right-to-left shunting of blood and hypoxemia
elevated resistance in the pulmonary arteries causes abnormal smooth muscle development and hypertrophy in the walls of the small pulmonary arteries and arterioles and right-to-left shunting via the ductus arteriosus or a foramen ovale, resulting in intractable systemic hypoxemia
State causes of Persistent pulmonary hypertension of the new-born
PPHN often secondary to parenchymal lung disease (such as meconium aspiration syndrome, pneumonia or respiratory distress syndrome) or lung hypoplasia (with congenital diaphragmatic hernia or oligohydramnios) but can also be idiopathic
When does neural tube normally close? [1]
CLOSURE OF NEURAL TUBE COMPLETE BY DAY 28
Name a risk factor for gastroschisis [1]
Secondary to IUGR
Describe pathophysiology of cleft lip [1]
Failure of maxilla to fuse with the medial nasal prominence
Describe the pathophysiology of cleft palate [1]
Failure of palatal shelves to fuse (from maxillary prominences)
Which pharnygeal arches beome the R and L common carotids and proximal R and L internal carotids? [1]
Which pharyngeal arch becomes the arch of aorta? [1]
1st = small part of maxillary arteries
3rd = R and L common carotids and proximal R and L internal carotids
4th = R side detaches from dorsal aorta subclavian. L side arch of aorta
Name two hormones that contribute to gestational diabetes [4]
Pathophysiology thought to be due to placental secretion of anti-insulin hormones ( cortisol and glucagon; hPGH (human placental growth hormone) and placental lactogen (HPL)
Hyperemesis gravidarum may be caused by a deficiency in which vitamin? [1]
B6 (Pyridoxine)
Define Gestational trophoblastic disease (GTD)
What is a partial mole? [1]
What is a monospermic complete mole? [1]
What is a dispermic complete mole? [1]
GTD: When the trophoblastic tissue that forms part of the blastocyst proliferates more aggressively than normal
Partial mole: two sperm fertilse an egg creating 69 chromosome
Monospermic mole: maternal chromosomes are lost AND paternal chromosomes double up to make 46 chromosome
Dispermic complete mole: maternal chromosomes are lost AND fertilisation by two sperm: 46 chromosome
How does Liddle’s syndrome present? [1]
What would the following sound like when ascultating:
- asthma / COPD
- pneuomonia / pulmonary oedema
- fixed upper airway obstruction
- pulmonary fibrosis
What would the following sound like when ascultating:
- asthma / COPD: wheeze
- pneuomonia / pulmonary oedema: coarse crackles
- fixed upper airway obstruction: inspiratory stridor
- pulmonary fibrosis: fine crackles
Give very brief overview of long term potentiation and depression
LTP:
- synapse fired and NMDA receptors activated due to Ca2+
- causes increase in AMPA receptors into spine of post-synaptic membrane
LTD:
- Involves a decrease in the number of AMPA receptors; They are removed from the spines in vesicles during LTD
