To learn Flashcards
An A level Biology teacher shows her students a diagram to illustrate base pairing in DNA
Which two bases are illustrating this interaction in the diagram?
Adenine : Adenine
Adenine : Thymine
Cytosine : Cytosine
Guanine : Cytosine
Guanine : Guanine
Guanine : Cytosine
A 40 year old woman develops involuntary and irregular movements of her limbs, neck, head, and face (chorea) and is referred to a consultant neurologist by her GP. Further testing reveals that the woman has Huntington’s disease, an autosomal dominant inherited disease caused by mutation of the huntingtin gene.
What type of mutation results in this disease?
- Deletion of 3 nucleotides resulting in loss of phenylalanine at position 508 (ΔF508)
- Frameshit mutation (+1 insertion)
- Increased number of CAG repeats
- Missense mutation resulting in a Glu to Val substitution
- Nonsense mutation resulting in a premature stop codon at position 508
CORRECT – Huntington’s is a trinucleotide repeat disorder. Trinucleotide repeat disorders result from errors in DNA replication leading to increasing numbers of repeated sequences of three nucleotides. In general, the greater the number of trinucleotide repeats, the greater the chance of exhibiting symptoms and the worse the clinical manifestations.
A 26 year old butcher slips holding a knife and badly cuts his arm. The bleeding from the wound stops within 10 minutes due to the process of haemostasis
What sequence of events occurs during this physiological process?
A platelet plug forms, arteries contact, fibrin filaments accumulate and trap red blood cells.
- A platelet plug forms, fibrin filaments accumulate and trap red blood cells, arteries contract.
- Arteries contract, a platelet plug forms, fibrin filaments accumulate and trap red blood cells.
- Arteries contract, fibrin filaments accumulate and trap red blood cells, a platelet plug forms.
- Fibrin filaments accumulate and trap red blood cells, a platelet plug forms, arteries contract.
Arteries contract, a platelet plug forms, fibrin filaments accumulate and trap red blood cells.
CORRECT – This is the correct sequence of events in haemostasis. The severed artery contracts, not enough to stop the bleeding but enough to decrease the pressure downstream (contraction doesn’t occur in veins but the pressure in them is much lower). A primary haemostatic plug of activated platelets then forms at the hole in the vessel, sticking to the injured vessel and the connective tissue outside it. This is fragile but may control the bleeding and forms in seconds to minutes. The secondary haemostatic plug of fibrin filaments forms as fibrin filaments stabilise the friable platelet plug into a blood clot. This forms in approximately 30 minutes.
A 42 year old woman presents her GP with a 12-week history of pain in the right upper quadrant of her abdomen and a low-grade fever. On examination, the woman is Murphy’s sign positive. The GP believes that the woman may have chronic cholecystitis and organises a biopsy. A histological section from this the biopsy is shown below:
What type of cell is indicated by the green arrows?
Macrophage
CORRECT – The word ‘macrophage’ means ‘big eater’. Before macrophages enter the tissue spaces and whilst they are circulating in the blood, they are called monocytes. Once they enter the tissue spaces, they are called macrophages (or histiocytes). Monocytes are made in the bone marrow and circulate in the blood for about six days. They then enter the tissues and become dormant until activated by a local challenge. Macrophages appear to live for many months and can replicate (unlike neutrophils). The macrophage is a very versatile cell and it is the mastermind of chronic inflammation and the immune response. They arrive at the site of inflammation after the neutrophils and then take over from them. Macrophages have many functions. They include phagocytosis (although not always as effectively as neutrophils, they are better at destroying some difficult to kill bacteria such as Mycobacterium tuberculosis), secretion of numerous (in the order of 100) substances that summon and activate other cells, presenting antigens to the immune system and initiation of the immune response, stimulating angiogenesis (the formation of new blood vessels) which is important in wound healing, inducing fibrosis and inducing fever, acute phase reaction and cachexia.
hypertrophy
Hypertrophy refers to an increase in tissue or organ size due to an increase in cell size without an increase in cell numbers.
healing by primary intention
Healing by primary intention occurs in wounds with dermal edges that are close together (e.g a scalpel incision). It is usually faster than by secondary intention, and occurs in four stages:
-
Haemostasis – the action of platelets and cytokines forms a haematoma and causes vasoconstriction, limiting blood loss at the affected area
- The close proximity of the wound edges allows for ease of clot formation and prevents infection by forming a scab
- Inflammation – a cellular inflammatory response acts to remove any cell debris and pathogens present
- Proliferation – cytokines released by inflammatory cells drive the proliferation of the fibroblasts and the formation of granulation tissue
- Angiogenesis is promoted by the presence of growth mediators (e.g VEGF), allowing for further maturation of the granulation tissue; the production of collagen by fibroblasts allows for closure of the wound after around a week
- Remodelling – collagen fibres are deposited within the wound to provide strength in the region, with the fibroblasts subsequently undergoing apoptosis
Secondary Intention
Healing by secondary intention occurs when the sides of the wound are not opposed, therefore healing must occur from the bottom of the wound upwards.
A 40 year old woman develops involuntary and irregular movements of her limbs, neck, head, and face (chorea) and is referred to a consultant neurologist by her GP. Further testing reveals that the woman has Huntington’s disease, an autosomal dominant inherited disease caused by mutation of the huntingtin gene.
What type of mutation results in this disease?
- Deletion of 3 nucleotides resulting in loss of phenylalanine at position 508 (ΔF508)
- Frameshit mutation (+1 insertion)
- Increased number of CAG repeats
- Missense mutation resulting in a Glu to Val substitution
- Nonsense mutation resulting in a premature stop codon at position 508
Increased number of CAG repeats
CORRECT – Huntington’s is a trinucleotide repeat disorder. Trinucleotide repeat disorders result from errors in DNA replication leading to increasing numbers of repeated sequences of three nucleotides. In general, the greater the number of trinucleotide repeats, the greater the chance of exhibiting symptoms and the worse the clinical manifestati
Name the 2 daughter cells produced by meiosis 1 in oogenesis.
Answer
The secondary oocyte and the first polar body (both of which are haploid with 23 chromosomes and 46 chromatids)
As sperm cells mature they move through between across the ……………. from the ………… compartment towards the …………. compartment of the seminiferous tubule.
As sperm cells mature they move between the sertoli cells from the basal compartment towards the adluminal compartment of the seminiferous tubule.
Which type of reaction is depicted in the graph below?
endergonic or exergonic
endergonic
the paradox of REM sleep
- EEG activity is similar to that seen during arousal (beta waves), however the person is difficult to rouse due to strong inhibition of the thalamus
- Muscle tone in most of the body is lost due to descending inhibition of LMNs by glycinergic fibres arising from the reticular formation and running down the reticulospinal tracts
- To stop us acting out our dreams e.g. sleep walking
- Eye movements and some other cranial nerve functions are preserved (e.g. nocturnal bruxism)
- Autonomic effects are seen including penile erection and loss of thermoregulation (how people die if they sleep without adequate shelter)
as we get deeper into sleep the ……. become more deactivated
thalamus
- less sneosry info and motor info having to pass through the thalamus
exam of a 2 month year old boy reveals a bulging fontanelle and a downward gaze. Most likely diagnosis
congenital hydrocephalus
types of MRI
CSF is dark on T1-weighted imaging and bright on T2-weighted imaging.
T2 - white water (inc fat which is water rich)
wher ein the ventricular system is a ventriculoperitonel shunt inserted
lateral ventricles
describe how the ventricular septum forms
- msucular portion grows upwards from the floor of the ventricles
- membranous portion derive dfro the endocardial cushions and grows ndownwards to fuse with the muscular portion
a ventircular spetal defect causes a left to right shunt. Give 2 other causes of left to right shunt
- atrial septal defect
- patent ductus arteriosus
define secondary amenorrhea
Secondary amenorrhea is defined as the cessation of regular menses for three months or the cessation of irregular menses for six months.
- having had previous periods before
cause sof secondary amenorrhea
PCOS
Weight loss
Stress
what hormone can be measured to reliably demonstatre ovulation has occured
progestrogen
at ovulation, the CL is formed–> secretes progesterone in the luteal phase –> showing ovulation hasa occured
first tst in a women with secondary amenorrhea
pregnancy test
where is RA in the hand most commonly found
metacarpophalangeal joint
signs of RA on x-ray
narrowing of joint space
juxta articular bony erosions
soft tissue swelling
deformity
signs of OA on X-raY
joint space loss, osteophyte formation, cyst formation and subchondral sclerosi
2 autoantibodies associated with RA
Rheumatoid Factor and anticitrullinated protein antibodies (ACPAs)
extra-articular features of RA
pulmonary fibrosis,
vasculitis,
skin ulceration,
lymphadenopathy,
peripheral neuropathy, splenomegaly,
episcleritis or
pericarditis.
blood supply to the nose
sphenopalatine and kkieselbach plexus
symptoms of sinusitis
Runny nose.
Stuffy nose.
Facial pain or pressure.
Headache.
Mucus dripping down the throat (post-nasal drip)
Sore throat.
Cough.
Bad breath
rare complication of sinusitis
venous sinus thrombosis
mechanism of action of apixiban
inhibits factor Xa- DOAC
stages of ehaling
Healing by primary intention occurs in wounds with dermal edges that are close together (e.g a scalpel incision). It is usually faster than by secondary intention, and occurs in four stages:
Haemostasis – the action of platelets and cytokines forms a haematoma and causes vasoconstriction, limiting blood loss at the affected area
The close proximity of the wound edges allows for ease of clot formation and prevents infection by forming a scab
Inflammation – a cellular inflammatory response acts to remove any cell debris and pathogens present
Proliferation – cytokines released by inflammatory cells drive the proliferation of the fibroblasts and the formation of granulation tissue
Angiogenesis is promoted by the presence of growth mediators (e.g VEGF), allowing for further maturation of the granulation tissue; the production of collagen by fibroblasts allows for closure of the wound after around a week
Remodelling – collagen fibres are deposited within the wound to provide strength in the region, with the fibroblasts subsequently undergoing apoptosis
state 4 cardiovascular compensatory mechanisms mediated by the symapthetic nervous system in hypovolaemic shock
vasoconstriction
venoconstriction
increased stroke volume
increased heart rate
under what circumstances is lactate produced
anaerobic respiration
how is alctate produced
lactate dehydrogenase converts pyruvate to lactate
how is lactate utilise dby the body
why does a pt with ischameic heart disease get itnense muscle cramps following vigorous exercise
reduced cardiac output (CO= SVxHR)
therefore oxygenated blood delivered less efficiently to respiring muscles
lactate builds up –> cramps
name 2 molecules that can cause metabolic acidosis
lactate
ketones
ATP
most likely causative organism of an exacerbation of COPD
Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae.
a 68 yea rold pt started smoking aged 26 and stopped 2 years ago. In the interim, she smoked an average of 40 cigs a day. Pack year?
40/20 x 40= 80 pack year
type 1 vs type 2 respiratory failure
type 1= low oxygen <8, normal CO2
Type 2= low oxygen, high CO2
3 steps GP should take regarding subsequent management of COPD after exacerbation
pulmonary rehab
rescue pack of antibiotics and steroids
flu vaccinations
method of investigating vaginal discharge
high vaginal swab
endocervical swab
2 risk factors for cotnracting a sexually transmitted infection
young age of first intercourse
multiple partners
alcohol and drug abuse
the sciatic nerve typically exits the pelvis via the greater sciatic forament infeiror tow hich muscle
piriformis
name the artery that accompanises the sciatic nerve at this point
superior gluteal artery
name given to degeneration of enrve caused by injury
wallerian
borders of the posteiror triangle
Anterior – posterior border of the sternocleidomastoid.
Posterior – anterior border of the trapezius muscle.
Inferior – middle 1/3 of the clavicle.
68 year old lady fell and found24 hours later. what would you expect to find if you measured the paitnet surine osmolarity and volume?
which components of the nephron and renal capillary network are involved in producing these changes to the osmolarity and volume of the urine?
increased osmolarity and decreased volume
loop of henle and vasa recta
name the hormone which regulated water reabsorption in the collecting duct and where it is synthesises and released from
ADH
produced in the hypothalamus and released by the PP
ADH MOA
Antidiuretic hormone stimulates water reabsorbtion by stimulating insertion of “water channels” or aquaporins into the membranes of kidney tubules.
what is health inequality
Health inequalities are unfair and avoidable differences in health across the population, and between different groups within society. Health inequalities arise because of the conditions in which we are born, grow, live, work and age.
name 4 social determinants
gender
education level
transportation system
homelessness
employment opportunity
according to wilkinson there is a clear relationship between income distribution and helath inequealities
rich countries dont necessarily have the best healthcare –> richer the country has the biggest health inequalities
egalitarian countries who priorities eveyrones health
how do you precisely measure PR interval on an ECG trace
measure from the beginning of P and end of R
main difference between first degree and second degree heart block on ECG
first degree –> lengthening of PR intervals (always followed by QRS)
second degree –>
mobitz I–> progressive lenghtening then drop of QRS
mobitz II–> fixed PR just dropage of QRS
difference between type 2i and type 2ii heartblock
Both Mobitz type 1 block and type 2 block result in blocked atrial impulses (ECG shows P-waves not followed by QRS complexes). The hallmark of Mobitz type 1 blockis the gradual prolongation of PR intervals before a blockoccurs. Mobitz type 2 block has constant PR intervals before blocks occur.
Which term is used to describe the cycle by which the lactate produced in skeletal muscle is converted back to glucose in the liver?
TCA cycle
Urea cycle
Cori cycle
Alanine cycle
cori cycle
Which condition would result due to hypothyroidism in a neonate?
Myxedema
Cretinism
Gigantism
Addison’s disease
Grave’s disease
cretinism
What is the half life of thyroxine (T4) in plasma?
~5-7 seconds
~5-7 minutes
~5-7 hours
~5-7 days
~5-7 weeks
~5-7 months
~5-7 years
5-7 days
The half-life of T4 is ~5-7 days; the half-life of T3 is lower at ~1 day.
What effect might the antacid Gaviscon® have on the absorption of iron?
Decrease the rate of iron absorption
Increase the rate of iron absorption
Decrease the rate of iron absorption
Name two intracellular protein-iron complexes that are used to store iron.
Ferritin and haemosiderin
Ferritin is a universal intracellular protein that stores iron and releases it in a controlled fashion. Ferritin is found in most tissues as a cytosolic protein, but small amounts are secreted into the serum where it functions as an iron carrier. A ferritin blood test is therefore a useful diagnistic. Haemosiderin is also an iron-storage complex and is only found within cells. Haemosiderin is complex of ferritin, denatured ferritin and other material. Unlike ferritin, the iron within deposits of haemosiderin is very poorly available.
If the BP drops below 60mmHg its V dangerous
- Activation of sympathetic nerves which cause systemic vasoconstriction
- Renal failure (not enough oxygen or nutrients due to systemic vasoconstriction)
- In response the kidneys try to increase perfusion and glomerular filtrationProstaglandins (NSAIDs inhibit prostaglandins so are not helpful for people with renal problems) are sent from the macula densa cells which causes dilation of the afferent arterioles
- Slightly increased GFR
- Flow through glomerulus increases
- Juxtaglomerular cells release renin (in response to low BP)
- Causes angiotensinogen to be converted into angiotensin 1
- In the lungs (vascular tissue) angiotensin 1 is converted to angiotensin 2
- Angiotensin 2 causes restriction of the efferent arterioles
- Increases blood flow to glomerulus to maintain GFR
A 58 year old man presents to his GP with a 2 month history of central crushing chest pain on exercise which is relieved on rest. The GP records an ECG (shown below).
What is the patient’s heart rate?
90 beats per minute
CORRECT – The rhythm is an irregular non-sinus rhythm (i.e the RR intervals are irregular). Therefore, the only way to calculate the heart rate it to count the number of R peaks that occurs within 30 large squares (6 seconds) and multiply it by 10. In this case 9 R peaks occur within 30 large squares, so 9 x 10 = 90 beats per minute.
skin terms
A 27 year old woman is diagnosed with Neurocardiogenic Syncope (NCS), a condition resulting from disturbances to the function of the autonomic nervous system.
What are the properties of the pre- and postganglionic neurones in the sympathetic branch of this division of the nervous system?
white matter
Funiculus (largest subdivision)
- A segment of white matter containing multiple distinct tracts
- Impulses travel in multiple directions (ascend or descend)
Tracts
- Found within funiculi
- An anatomically and functionally defined white matter pathway connecting two distinct regions of grey matter
- Impulses travel in one direction
- Ascending tracts in blue (sensory)
- Descending tracts in green (motor)
Fasciculus
- Subdivision of tracts which supplies a distinct region of the body
- Fasciculus cuneatus (lateral)- supplies upper half of body
- Fasciculus gracilis (medial)- supplies lower half of body
causes of parasthesia in fingers during panic attack
This hypocalcaemia related to alkalosis is responsible for the paraesthesia often seen with hyperventilation.
A 48-year-old male has been admitted with a 24 hour history of abdominal distention and profuse vomiting. A CT scan reveals a large mass causing bowel obstruction. As part of the patient’s assessment, the surgical registrar requests that you check his blood gas (on air), with the results shown below:
PaO2: 12.7 kPa (11 – 13 kPa) || 95.2 mmHg (82.5 – 97.5 mmHg)
pH: 7.50 (7.35 – 7.45)
PaCO2: 5.5 kPa (4.7 – 6.0 kPa) || 41 mmHg (35.2 – 45 mmHg)
HCO3-: 29 (22 – 26 mEq/L)
BE: +3 (-2 to +2)
metabolic alkalosis
As a result of this patient’s profuse vomiting, they have lost significant amounts of HCL (e.g. stomach acid).
This results in a net loss of H+ ions, meaning less H+ to bind to HCO3– and therefore more free HCO3– in the system.
In addition, as a result of vomiting, the patient is volume depleted, which results in the release of aldosterone and other mineralocorticoids which in turn increase HCO3–reabsorption by the kidneys, further increasing the amount of free HCO3– in the serum.
how can sepsis cause metabolic acidosis
This patient has presented profoundly septic, with fever, hypotension and evidence of reduced end-organ perfusion (reduced urine output).
Reduced end-organ perfusion causes tissue hypoxia resulting in cells resorting to anaerobic respiration to generate energy.
Anaerobic respiration produces lactic acid as a byproduct, which has resulted in the addition of acid to the patient’s serum causing lactic acidosis.
dermatomes and myotomes are derived from
somites
A dermatome is an
area of skin supplied by a single spinal nerve.
A myotome is a
group of muscles innervated by a single spinal nerve.
dermatomal map of the whole body
myotomal movement
C4: shoulder shrugs
C5: shoulder abduction and external rotation
C6: elbow flexion and wrist extension
C7: elbow extension and wrist flexion
C8: thumb extension and finger flexion
T1: finger abduction
L2: hip flexion
L3: knee extension
L4: ankle dorsiflexion
L5: big toe extension
S1: ankle plantarflexion
S4: bladder and rectum motor supply
Plexuses
We can classify groups of nerves into plexuses:
- Cervical plexus (C1 – C4): innervates the diaphragm, shoulders and neck.
- Brachial plexus (C5 – T1): innervates the upper limbs.
- Lumbosacral plexus (L2 – S1): innervates the lower extremities.
where is seratonin predominatley produced
the raphe nuclei
where is NA peroduced
locus coeruleus
where is ACh produced
nucleus basalis
where is dopamine released from
4 different pathways
mesolimbic (think schizophrenia)
mesocortical
nigrostriatal (think parkinsons)
tubuloinfundibular
neck lumps
midline
- thyroglossal cysts- move on tongue protrusion
- thryoid pathology- move on swallow
lateral
- Branchial cysts - wont move on swallowing or tongue protrusion (congenital)
kidney function equations
Clearance = [U]x x V / [P]x
Excretion= filtration - (reabsorption + secretion)
therefore secretion = excretion- filtration (if not reabsorption)
filtration= [P] x GFR
excretion = [U] x V
rtidk ratio vs odds ratio calc
risk ratio - work out percentage of both incidence and then divide by eachother e.g. (20/100)/ (30/100)
odds ratio- need to work out ratios and then divide them into eachother e.g. 1:1.8 to 1:1.2 = 1.8/1.2= 1.5
giant cells
touton- fat necrosis
langhans- TB
foreign body
sensory innervation of the pharynx
Nasopharynx (maxillary nerve CN V2)
Oropharynx ( glossopharyngeal nerve CN IX)
Laryngopharynx (vagus nerve CNX)
motor innervation of the pharynx
CNX -Vagus innervates all muscles
Except stylopharyngeus (glossopharyngeal nerve (CN IX)
larynx anatomy
- Thyroid (2 lamina – superior and inferior horn)
- When one lamina meets the other lamina = laryngeal prominences – Adams apple
- Cricoid cartilage -below thyroid
- inferior horn of thyroid cartilage articulates with the cricoid cartilage- synovial joint
- thicker at the back than front (signet ring)
- Retinoid cartilage- sits on the cricoid cartilage
- Epiglottis- attached by its stalk to the inner surface of the thyroid cartilage
laryngeal inlet made up of the
aryepiglottic folds and epiglottis
false and true vocal cords
folds formed by ligaments/membranes and cartilages
- Quadrangular membrane (inferior boundary)- false vocal cord
- Superior extension of the cricothyroid membrane- true vocal cord
the larynx with the exception of the true vocal cords are lined with
pseudostratified ciliated columnar epithelium
movement of vocal cords
Vocalis muscle run along the length of the vocal cords
muscles associated with arytenoid cartilage causes widening of aperture –>responsible for moving outwards and inwards of vocal cords
- important one= posterior cricoarytenoid (only intrinsic muscle that acts to abduct vocal cords)
- all the other intrinsic muscles will act to adduct vocal cords
posterior cricoarytenoid
only intrinsic muscle that acts to abduct vocal cords
most intrinsic muscles of the larynx supplies by the
recurrent branch of the laryngeal nerve
- e.g. to open and close and cough
cricothyroid muscle supplies by the
external branch of the superior laryngeal nerve
cricothryoid
- Intrinsic muscle
- Found on the outside of the cartilages
- external branch of superior laryngeal nerve
- will increase tension of vocal cords- important for reaching higher pitches
external branch of the superiro laryngeal supplying the cricothyroid muscle is closely associated to and at risk during
(closely related to superior thryoid artery)–> can be damaged during thryoid surgery
- will cause hoarseness of voice particulalry when attempting higher pitched sounds
torsades de pointes
polymorphic ventricular tachycardia characterized by a gradual change in amplitude and twisting of the QRS complexes around an isoelectric line on the electrocardiogram.
which HPV cause cancer
HPV 16 and 18
which nucleotides are purines and which are pyridines
purines
adenine and guanine
pyrimidines
thymine and cytosine and uracil
Angiotensin 2 causes restriction of the …….. arterioles in response to hypovolemia or reduced GFR
efferent
- think of the effects of ACEi and ARB
prostaglandins cause dilation of the ……… arterioles in response to systemic vasconstriction (e.g. in hypovolemia) to ensure blood supply to the kidney
afferent
–> think about the effect of NSAIDS
balantis
inflammation of the glans penis
posthitis
inflammation of the foreskin
LUTS are usually either
Voiding (suggestive of bladder outflow obstruction)
- Hesitancy
- Poor flow
- Post micturition dribbling
Storage
- Nocturia
- Urgency
- Frequency
physical BOO (bladder outflow obstruction)
urethra
- phimosis
- stricture
prostate
- benign (BPH)
- malignant
- bladder neck
dynamic BOO
- prostate
- bladder neck
neurological BOO
lack of coordination between bladder and urinary sphincter
- UMN
spraying of urine suggests
urethral stricture
Hydrocele (adult)
imbalance of fluid production and resorption between tunica albuginea and tunica vaginalis
Examination
- Testis not palpable separately
- Can get above
- Transilluminates
*
most common breast tumour
fibroadenoma causes by fibrocystic change
- Present with a mass, usually mobile, or mammographic abnormality*
- ‘Breast mouse’ – mobile and elusive*
Phyllodes tumours
very similar to fibroadenomas
- Most present in 6th decade
- Have potential to be malignant but present much later
Acute mastitis
Almost always occurs during lactation
Usually Staphylococcus aureus infection from nipple cracks and fissures
Erythematous painful breast, often pyrexia
Usually treated by expressing milk and antibiotics (stopping breast feeding)
most type of breast cancers are
adenocarcinomas
- Most common in the upper outer quadrant (50%)
- Other malignant tumours are very rare e.g. primary sarcomas such as angiosarcoma
*
breast cancer risk factors
Early menarche (< 11 years)
Late menopause
Obesity and high fat diet
Exogenous oestrogens – HRT slightly increases risk (1.2-1.7 times), long term users of COCP possibly have an increased risk
how do we classify breast carcinoma
in situ
invasive
ductal
lobular
Invasive carcinoma
Neoplastic cells have invaded beyond BM into stroma
- Can invade into vessels and can therefore metastasize to lymph nodes and other sites
- By the time a cancer is palpable more than half of the patients will have axillary lymph node metastases
- Peau d’orange – involvment of lymphatic drainage of skin
How does breast cancer spread?
Lymph nodes via lymphatics– usually in the ipsilateral axilla
Distant metastases via blood vessels – bones (most frequent site), lungs, liver, brain
breast cancer prognosis
stroke
a neurological deficit attributed to an acute focal injury of the central nervous system (CNS) by a vascular cause, including cerebral infarction, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH)
peripheral modulation of pain
Within the substantia gelatinosa in the dorsal horn
- Lamina 1 and 5 are where pain fibres transmit
- E.g.
- Stimulation of Adelta + C fibres due to tissue damage
- Enters lamina 1 and 5
- Ascends the spinal cord via the spinothalamic tract and projects to the thalamus
- Receive pain sensation in the primary somatosensory cortex
- The tissue damage also sends inhibitory signals to the substantia gelatinosa- technically would make it feel as painful as possible
- How do we modulate this? By ‘rubbing it better’
- Ab fibres are activated by rubbing the tissue and send stimulatory signals to the substantia gelatinosa
- Send inhibitor signals to lamin 1 and 5, reducing amount of pain received by the thalamus
characteristics of poorly differentiated cells (6)
- Increased nuclear size
- Increases nuclear to cytoplasmic size
- Increased nuclear staining (hyperchromasia)
- Increased mitotic figures
- Abnormal mitotic figures
- Variation in size and shape of cells and nuclei (pleomorphism)
