Bio Flashcards
(432 cards)
1
Q
Gas exchange
A
ability of lungs to transfer air in and out effectively
2
Q
Ventilation
A
movement of air to alveoli providing O2 and removing CO2
3
Q
Minute ventilation
A
amount of air exchanged per minute.
Tidal volume x respiratory rate
4
Q
Hypoxaemia
A
low levels of O2 in blood stream
5
Q
Hypercapnia
A
high levels of CO2. Occurs when person does not breathe out efficiently
6
Q
What does V-Q mismatch stand for?
A
Ventilation-perfusion mismatch
7
Q
What are the 2 circumstances known as V-Q mismatch?
A
1) Obstruction in air passages means air is unable to get to alveoli, so blood passing around those alveoli do not receive O2.
2) Conversely, areas of lungs where there are circulatory issues preventing blood flow can be well oxygenated.
8
Q
Perfusion
A
amount of blood flow to alveoli
9
Q
Where in the lung is perfusion better?
A
at the base
10
Q
Pulmonary shunt
A
perfusion without ventilation
11
Q
Deadspace
A
ventilation that does not partake in gas exchange
12
Q
Atopic asthma
A
triggered by environment. Common. Inflammation caused by systemic IgE production.
13
Q
Non atopic asthma
A
Rare. Inflammation not caused by exposure to allergen. Inflammation caused by local IgE production.
14
Q
Differences in bronchiole layers with asthma
A
more goblet cells, mast cells, T helper cells, neutrophils and larger smooth muscle cells
15
Q
3 characteristics of asthma
A
airflow obstruction, bronchioles hyper responsive due to histamine release and inflammation due to increased neutrophils
16
Q
How does the body react to asthma - process
A
Inhale antigen, engulfed by dendritic cells which activates them. Columnar epithelial cells release thymic stromal lymphocytes which causes the dendritic cells to produce chemokines to attract T helper 2 cells to the lungs. These stimulate plasma cells and promote IgE production. These bind to mast cells to create a complex that the antigen will bind to, causing it to release histamine which causes constriction.
17
Q
Haldane effect
A
haemoglobin can hold either O2 or CO2, not both but will prioritise O2. If they can’t get rid of the CO2, they will take it back round. If given too much O2, will dump the CO2.
18
Q
VQ mismatch when COPD patient given high flow oxygen
A
Chemoreceptors vasoconstrict areas that aren’t gas exchanging properly and move the blood elsewhere. When given high flow O2, chemoreceptors will open these vascular beds and allow blood to go to areas that still aren’t gas exchanging, so the blood will return to circulation full of CO2 and very little O2.
19
Q
Pertussis
A
whooping cough
20
Q
Hypersensitivity
A
altered immune response to an antigen that causes the person to become ill.
21
Q
Autoimmunity
A
body creates antibodies to fight own cells
22
Q
alloimmunity
A
body creates antibodies to fight foreign antigen
23
Q
4 types of hypersensitivity reactions
A
1) IgE reaction
2) Tissue specific reaction
3) Immune complex mediated reactions
4) Cell-mediated reactions
24
Q
Innate immunity
A
1st line of defense. Phagocytes, dendritic, mast, complement, mediators
25
Adaptive immunity
2nd line of defence. B, T killer and helper cells.
26
Biochemical mediators and their functions
histamine - redness
bradykinin - pain
leukotrienes and prostaglandin - vasodilation
they all cause the cells of the vessel endothelial lining lining to retract so leukocytes and plasma enter the surrounding tissue
27
IgG
antiviral, antibacterial and antitoxin
28
IgA
in saliva, tears and colostrum. Acts locally on mucosa in respective tissues, preventing viruses from attaching to epithelium.
29
IgM
largest. Helps digest and eliminate organisms. Found in foetus.
30
IgE
allergic reactions and parasites.
31
What does an antibody link to?
cell membrane
32
What are some pleural membrane issues?
fluid can accumulate between layers of lung, in intrapleural space or there can be a hole within pleura, so lung can't be pulled out easily.
33
Visceral pleura
adheres to lungs
34
Parietal pleura
sac where lung sits
35
Functions of pleura
allows lung to change shape and prevents it collapsing
36
Pleuritis
inflammation of parietal pleura. Shows as shortness of breath, chest pain and pleural rub
37
Pleural effusion
accumulation of fluid in pleural space, usually as result of inflammation of pleura. Less breath sounds and decreased lung expansion
38
Pneumothorax
```
accumulation of air in pleural space.
1) spontaneous - ruptured bullae
2) open - external trauma
Causes lung to collapse
will be no breath sounds
```
39
Tension pneumothorax
overaccumulation of air in pleural space, usually as result of valve mechanism. air enters during inhalation but then cannot leave, increase in pressure causes lung to skip. LIFE THREATENING
40
Pneumonia
lung inflammation caused by infection. affects lower airway and causes development of secretions which build up and block airways, causing lung collapse.
41
Causative agents of pneumonia
Bacteria - strep, haemophilus influenza, legionella, staph, mycoplasma
Virus - influenza, RSV
Fungi
42
How does body react to bacterial pneumonia?
Bacteria enters alveoli; macrophages produces cytokines. These cause vasodilation and increased vascular permeability - causes fluid to shift from vascular space to alveoli, leading to congestion.
43
How does body react to viral pneumonia?
Virus infects respiratory cell and releases genetic material. Uses hosts proteins to replicate - damages cell, creating cell debris, initiating immune response. macrophages produces cytokines. These cause vasodilation and increased vascular permeability - causes fluid to shift from vascular space to alveoli, leading to congestion.
44
How does body react to fungal pneumonia?
Fungi spores inhaled - travels to alveoli where it grows into fungal ball. Can spread, causing systemic effect.
45
Effects of lung infection
fluid filled alveoli, increased mucus secretion, narrowed airways and bronchi constriction.
46
Consolidation
the process that fills the alveoli with fluid, pus, blood and cells resulting in lower diffuse capacity.
47
lobar pneumonia
affects whole lobe. 4 stages:
1) congestion
2) red hepatization
3) grey hepatization
4) resolution
48
Broncho pneumonia
starts with bronchioles, moves to alveoli. affects patches.
49
Tool used to assess severity of pneumonia
CURB-65. Score greater than 2 = hospitalisation.
50
Transmission of pneumonia
- inhalation of infected agents
- aspiration of organisms that colonize oropharynx
- aspiration of stomach content
- haematological spread
- direct innoculation
51
complications of pneumonia
abscess, empyema, bacteremic dissemination
52
Empyema
pockets of pus that have collected inside a body cavity
53
4 investigations for pneumonia
chest xray, sputum testing, urine antigen testing, blood testing
54
Management and treatment of pneumonia
O2, IV fluids, pain management, antibiotics
55
Stridor
harsh noise on inspiration due to narrowing of larynx
56
Rhonchi
low pitched, gurgling noises with severe infection
57
Grunting
typical in babies when they trap air in lower airway by prematurely closing off glottis at end of breath.
58
Bronchospasm
bronchi spasm and constrict, narrowing airway
59
Laryngospasm
narrowing of larynx. Can fully close airway and prevent breathing.
60
Apnoea
absence of breathing
61
dyspnoea
difficulty breathing
62
Tachypnoea
fast breathing
63
Crackles
sound made when secretions not fully cleared by coughing
64
Cor pulmonale
abnormal enlargement of right side of heart due to disease in lungs and/or pulmonary blood vessels
65
Epistaxis
nose bleed
66
Haemoptysis
coughing up blood
67
Hypoxaemia
low concentration of oxygen in blood
68
Hypoxia
part of body deprived of oxygen at tissue level
69
What happens to foetal circulation after birth?
systemic vascular resistance rises.
alveoli expands and vessels around them dilate.
Pulmonary pressure decrease. 6-8 wks before pulmonary vascular resistance is normal.
Increase in left atrial pressure (blood returns to heart from pulmonary tissue) forces septum primum against septum acundum, closing foramen ovale.
Ductus arteriosus and ductus venosus close (leaves ligamentum venosum)
Umbilical vein and arteries are infiltrated with fibrin and also become ligaments.
70
Transporter carriers
carry single molecule in one direction across membrane
71
Symporter carriers
carry two molecules in same direction across membrane
72
Antiporter carriers
carry two molecules in different directions across membrane
73
Pharmacodynamics
what drug does to body
74
Pharmacokinetics
what body does to drug
75
4 kinds of protein drug targets
enzymes, carrier/transporter, ion channels, receptors
76
How does drug work with ion channels?
drug facilitates opening or blocking of channel
77
How does drug work with enzyme?
drug inhibits enzymes by binding to it
78
How does drug work with carrier/transporter?
drugs inhibit or facilitate transport of molecules that use carriers
79
How does drug work with receptor?
drug will bind to receptor and either mimic or block body's own natural chemical signals
80
Agonist
drugs that mimics body's signal, enhances effect
81
Antagonist
drugs that block body's signal, blocking effect
82
Two components of drug-receptor interactions
Binding of drug to receptor, governed by affinity
| Activation of response, governed by efficacy
83
Drug potency
combination of affinity and efficacy
84
Competitive antagonist
competes with agonist/body's signal for receptor binding
85
Irreversible antagonist
dissociates from receptor very slowly or not at all, so no change occurs when additional agonist added
86
non competitive antagonist
does not affect agonist binding, instead interrupts chain of events after
87
chemical antagonism
antagonist combines with drug in solution such that the effect of the active drug is lost
88
Pharmacokinetic antagonism
VERY COMMON. Antagonist reduces concentration of another drug by altering how it is passed through the body
89
Physiological antagonism
antagonist has opposing biological action of agonist so tends to cancel action out
90
4 main stages of pharmacokinetics
absorption, distribution, metabolism and excretion
91
What are the 4 ways that drugs can cross membranes?
- diffusion through lipid
- diffusion through aqueous membrane
- combination with carrier molecule
- pinocytosis
92
Where is carrier mediated drug transport important?
renal tubule, biliary tract, blood-brain barrier and GI tract
93
Bioavailability
proportion of drug that reaches circulation
94
Where does absorption of drugs mainly occur and why?
in the small intestine because of the large absorptive surface area of the villi and microvilli of the ileum
95
Why does pH matter in drug absorption?
it makes drugs more/less lipid soluble
96
Factors affecting drug absorption
```
rate of gastric emptying
disease
transit time through gut
blood flow
age
```
97
Plasma-protein drug binding
some drugs exist in plasma bound to plasma proteins, but only the free, unbound drug can exert a pharmacological effect
98
Factors that affect drug distribution
```
adiposity
plasma protein concentration
blood flow
membrane permeability
body water content
```
99
hypertonic
higher concentration of solute than water
100
hypotonic
higher concentration of water than anything else
101
Carcinogen
a substance or situation that results in cancer developing
102
Carcinoma
arises from epithelial tissue
103
Leukaemia
tumour that starts in blood-forming cells
104
Lymphoma
tumour that starts in lymphatic tissue
105
Metastases
spread of cancer cells from the site of the original tumour to elsewhere in the body. Different cancers have different patterns of spread.
106
Neoplasm
abnormal mass of cells
107
Sarcoma
tumour starting in connective tissue
108
Tumour
an abnormal growth resulting from uncontrolled proliferation of cells. It serves no physiological function for the person.
109
Benign tumour
grows slowly, well defined capsule, not invasive, look like the tissue where they occur, don’t metastasize
110
Malignant tumour
grows rapidly, not encapsulated, invade local structures and tissues, poorly differentiated, may not be able to determine the tissue of origin, spread to distant areas of the body (via blood and lymph). Cells in a malignant tumour typically have an irregular sized and shaped nucleus with a loss of normal tissue structure.
111
Autonomy
cell that works independently from other cells (as a cancer cell)
112
Angiogenesis
development of new blood vessels
113
Apoptosis
programmed cell death
114
Chemotherapy
encompass medications that can affect the vulnerability in the cell wall
115
Epigenetics
involves the change in gene coding which doesn’t change DNA sequencing but ‘switches’ genes on or off, often in the expression of RNA
116
Oncogene
a gene that in its normal state (as a proto-oncogene) makes (synthesises) proteins to support the replication of cells. Once it mutates into an oncogene, it supports the replication of cancer cells.
117
Silencing
chemical changes can silence a gene, without it mutating. Silencing a tumour suppressing gene can mean a cancer then develops
118
Tumour marker
substance produced by a tumour cell which is either present on the tumour cell or in blood, spinal fluid or urine, eg Prostate Specific antigen (PSA)
119
What happens during deep wound healing?
blood clot forms during inflammatory response - loosely unites the wound edges.
Migratory phase - clot becomes scab + epithelial cells migrate beneath to bridge wound. Fibroblasts begin synthesizing scar tissue and damaged blood vessels begin to regrow. The tissue filling the wound is called granulation tissue.
Proliferative phase - growth of epithelial cells, deposition of collagen fibres and continued growth of blood vessels.
Maturation - scab sloughs off once the epidermis has been restored to normal thickness. Collagen fibres become more organized, fibroblasts decrease in number and blood vessels are restored to normal.
120
Primary Dysmenorrhoea
painful menstruation which occurs with the release of a substance called prostaglandin, which constricts blood vessels and stimulates the uterine muscle to contract, increasing the sensitivity of the nerves to pain.
121
Primary Amenorrhoea
lack of menstruation
122
Polycystic ovaries
a disease where instead of follicles developing and releasing each month, cysts develop within the ovary.
123
Salpingitis
a commonly seen condition where the uterine (fallopian) tubes become inflamed.
124
Oophoritis
inflamed ovaries
125
Prolapse
pushing of one organ into another
126
Endometriosis
uterine tissue that is out of place
127
Galactorrhoea
the excess secretion of milky substances from the nipple when the woman is not breast-feeding or pregnant.
128
Gynecomastia
overdevelopment of breast tissue in men.
129
Cryptorchidism
where the testes don't descend fully in the first few months after birth and stops in the abdomen.
130
Orchitis
infection of testes
131
Benign prostatic hyperplasia
an enlarged prostate gland which can compress the urethra giving urinary problems.
132
Serum osmolality
concentration of ions in blood plasma
133
Acute renal failure definition
reversible decrease in glomerular filtration rate
134
What are the signs of acute renal failure?
decreased glomerular filtration rate
sudden increase in creatinine level
decreased urine output
135
Pre renal causes of ARF
sudden increase in BP or flow obstruction in kidneys
136
Intra renal causes of ARF
```
direct damage to kidneys
inflammation
infection
drugs
autoimmune disease
```
137
Post renal causes of ARF
obstruction of urine flow (kidney stones, bladder injury, tumour etc.)
138
4 types of intrarenal failure
- acute glomerular nephritis
- acute tubular necrosis
- acute interstitial nephritis
- vascular
139
Two changes that cause a decrease in glomerular filtration rate
vascular or tubular
140
Atrophy
decrease in cell size
141
Hypertrophy
increase in cell size
142
Metaplasia
reversible change where one adult cell is replaced by another type of adult cell
143
Dysplasia
irregular set of cells that develop
144
Apoptosis
pre programmed cell death
145
Haematopoiesis
formation of blood cellular components
146
neutrophils
first at site of infection
147
basophils
allergy and parasitic
148
eosinophils
allergy
149
monocytes
circulating macrophages - turn into macrophages or dendritic cells
150
megakaryocytes
release platelets for clotting
151
Angiogenesis
new vessel formation and maturation
152
Acute leukaemia
comes from most acute cells (blasts).
Acute lymphoblastic leukaemia - B cell and T cell
acute myeloid leukaemia - myelo, mono and megakaryo
153
Chronic leukaemia
Chronic lymphoid leukaemia comes from B cells - travel to lymphnode, spleen and liver, which all enlarge. L.N creates generalised lymphnode nopathy, leading to a small lymphocytic lymphoma. This can create a diffuse B cell lymphoma.
154
Sickle cell anemia
genetic disease where red blood cells take the shape of a sickle, allowing them to be more easily destroyed.
155
Vaso occlusion
sickle red blood cells get stuck in capillaries. This can clog up bones, leading to a wide number of issues.
156
Effect of repeated sickling
damages cell membrane, causing haemoglobin to spill out. This is recycled by haptoglobin which lead to unconjugated bilirubin - causing scleral icterus, jaundice and bilirubin gallstones.
157
Extra treatment for sickle cell anemia in children
prophylaxis, penicillin and polysaccharide vaccine. Prevents sepsis and meningitis.
158
Primary intention
wound is clean, little/no tissue loss. Tissue edges brought together with stitches, staples etc.
159
Secondary intention
wound edges cannot be brought together because of extensive tissue loss.
160
Tertiary intention
would edges could be brought together but not done immediately due to contamination or infection.
161
hypertrophies
abnormal enlargement of a part or organ; excessive growth
162
What medication is used in asthma as an anti-inflammatory to reduce the level of inflammation?
corticosteroid
163
What does the MHC or HLA system do?
triggers the changing of monocytes into macrophages to engulf invading organisms.
164
Which of the tissue mediators creates the feeling of pain?
Bradykinin
165
Which organs are involved in the development and storage of T and B lymphocytes?
thymus, kidney and liver
166
Which receptors sense a change in the concentration of dissolved particles in the blood stream?
osmoreceptors in the hypothalamus detecting osmolarity
167
Diabetes insipidus
not enough ADH is produced which means the kidney cannot make enough concentrated urine and too much water is passed from the body.
168
The force of the hydrostatic pressure is produced by?
blood pressure
169
proto-oncogenes
normal genes that help cells grow
170
oncogene
cancer causing
171
tumour suppressor genes
encode for proteins that are involved in inhibiting the proliferation of cells
172
stages of carcinogenesis
initiation, promotion and progression
173
carcinoma
Epithelial cell cancer
174
sarcoma
cancer in supportive and connective tissue cells
175
lymphoma
cancer in glands or nodes in the lymph system
176
myeloma
cancer in plasma cells in the bone marrow
177
leukaemia
blood cell cancer
178
Which processes occur within the S-phase of the cell cycle?
replication of DNA and centrosomes
179
What is the rule of 9s?
Used in burns, the entire surface of the human body is divided into 11 areas, with each given a value of 9%. This adds up to 99% of the surface of the body, with the groin being the final 1%.
180
What is endometriosis?
a condition where tissue similar to the lining of the womb starts to grow in other places, such as the ovaries and fallopian tubes.
181
In premenstrual tension, hormonal levels can change quickly resulting in mood changes, depression, irritability and aggression.
What substances in the body are most likely to be linked to these symptoms developing?
Neurotransmitters eg serotonin
182
What is oophoritis?
inflammation of ovaries
183
What is prolapse?
when 1 or more of the organs in the pelvis slip down from their normal position and bulge into the vagina.
184
balanitis
infection of male glans
185
cryptprchidism
undescended testes
186
Difference between adult and foetal haemoglobin
Foetal haemoglobin has a higher affinity for oxygen so sats might be lower
187
Signs of cancer - CHILDREN
```
C - continuous unexplained weight loss/fatigue
H - headaches with vomiting
I - increased oedema or pain
L - lump or mass
D - development of whiteness in pupil of eye
R - recurrent or persistant fevers
E - excessive bruising/bleeding
N - noticeable pallor/anaemia
```
188
treatments for cancer
chemotherapy, surgery, radiation, stem cell transplantation, steroid therapy, biological agents
189
How many cells thick is a normal alveolus?
1
190
FEV1
measure of air flow rate through the lungs
191
What medication is used in asthma as an anti-inflammatory to reduce the level so inflammation?
corticosteroid
192
How could obesity affect excretion of drugs?
Increased BP and impaired renal function
193
What would be a normal value for intracranial pressure?
0-15 mmHg
194
If eyes are different sizes, which nerve is being affected?
oculomotor
195
Which sympathetic response is mismatched with its body part?
stomach - decreased mobility
196
Which structure would the medulla oblongata potentially move through to cause brain stem death?
foramen magnum
197
What is the sequence of the vertebrae, starting at the head and moving down the body?
cervical, thoracic, lumbar, sacral, coccyx
198
What is the name given to the first cervical vertebra on which the skull is attached?
atlas
199
How could obesity affect absorption of IM/SC drugs?
thick layer of adipose tissue with impaired blood flow to peripheries
200
Allodynia
pain resulting from a stimulus (such as light touch) that does not normally elicit pain.
201
If eyes are different sizes, which nerve is likely to be being compressed?
Cranial nerve 3 - oculomotor
202
How could obesity affect excretion of drugs?
Increased BP and impaired renal function
203
What is FEV1?
measure of air flow rate through lungs
204
Which organelle within the cell changes the proinsulin to insulin and also produces a molecule of c-peptide?
ribosomes on ER
205
Hypoalgesia
diminished response to normally painful stimuli.
206
Hyperesthesia
increased sensitivity to stimulation.
207
Hypesthesia
diminished sensitivity to stimulation.
208
ventricular fibrillation
A serious heart rhythm problem in which the heart beats quickly and out of rhythm. No clear waves
209
Paresthesia
an abnormal sensation, spontaneous, or evoked.
210
Allodynia
pain resulting from a stimulus (such as light touch) that does not normally elicit pain.
211
If eyes are different sizes, which nerve is likely to be being compressed?
Cranial nerve 3 - oculomotor
212
What is FVC?
forced vital capacity - determines the amount of air that can be forcibly exhaled
213
What is FEV1?
forced expiratory volume - amount of air you can force from your lungs in one second
214
Tidal volume
the volume of air moved between one normal inhalation and one normal exhalation.
215
Inspiratory reserve volume
The amount of extra air inhaled — above tidal volume — during a forceful breath in.
216
Which are more potent: agonists or antagonists?
agonists
217
ventricular fibrillation
A serious heart rhythm problem in which the heart beats quickly and out of rhythm. No clear waves
218
What medication can be used to treat hypertension?
diuretics
219
What can cause plaque formation in brain?
Abnormal enzymic breakdown of B-amyloid associated protein
220
glucose and water equation
C6H12O6 + 6O2 ↔ 6CO2 + 6H20
221
gluconeogenesis
breaking down fats
222
glucogenolysis
breakdown of glycogen to glucose-1-phosphate and glycogen.
223
effect of insulin on gluconeogenesis and glycogenolysis
decreases both
224
What check occurs in G2 of cell cycle?
The cell checks for any incomplete replication of the DNA prior to mitosis
225
5 stages of embryonic lung development
Day 22 - buds appear from primitive oesophagus
Embryonic (4-7wks) - lung bud, trachea and bronchi, pulmonary vein and artery
Pseudoglandular (7-17wks) - conducting airways, terminal bronchioles
Canalicular (17-26wks) - primitive alveoli, type l and ll cells, surfactant synthesis
Saccular (27-36wks) - alveolar saccules, extracellular matrix, neural network maturation
Alveolar (36wks - 2yrs) - expansion of gas exchange area, nerves and capillaries
226
Embryological lung issues
failure of oesophagus to form as lung buds create a blind pouch, resulting in oesophagus atresia.
Can be connected to trachea causing tracheal-oesophageal fistula
227
role of osteoblasts
build bone
228
role of osteoclasts
break down bone
229
what are osteocytes?
mature bone cell
230
What happens during G1 of cell cycle?
duplicates organelles and cytosolic components. Checks DNA for damage, if its growing enough and that it has enough resources
231
what is an osteon?
functional unit of compact bone
232
difference in children's airway anatomy
large tongue and tonsils, floppy epiglottis, short trachea, narrow airways, higher larynx, respiratory muscles developing
233
How do we stage tumours? 3 factors
Tumour - size, location, local extent
Node - spread?
M - metastatic
234
5 stages of embryonic lung development
Embryonic (4-7wks) - lung bud, trachea and bronchi, pulmonary vein and artery
Pseudoglandular (7-17wks) - conducting airways, terminal bronchioles
Canalicular (17-26wks) - primitive alveoli, type l and ll cells, surfactant synthesis
Saccular (27-36wks) - alveola saccules, extracellular matrix, neural network maturation
Alveolar (36wks - 2yrs) - expansion of gas exchange area, nerves and capillaries
235
Embryological lung issues
failure of oesophagus to form as lung buds create a blind pouch, resulting in oesophagus atresia.
Can be connected to trachea causing tracheal-oesophageal fistula
236
coanal atresia
congenital disorder where the back of the nasal passage is blocked, usually by abnormal bony or soft tissue due to failed recanalization of the nasal fossae during fetal development.
237
cystic fibrosis
defect on single chromosome 7q31.2 - should code for regulator which controls passage of chloride across cell membrane. In CF, ability to reabsorb sodium and chloride is lost, so sweat is salty, secretions are thick and hard to expel
238
In which part of the cell cycle do cells exit?
G0
239
What happens during G1 of cell cycle?
duplicates organelles and cytosolic components. Checks DNA for damage, if its growing enough and that it has enough resources
240
What check occurs during the mitotic phase?
are the chromosomes lined up correctly?
241
senescence
loss of a cell's power of division and growth.
242
How do we stage tumours? 3 factors
Tumour - size, location, local extent
Node - spread?
M - metastatic
243
How does oedema occur?
when small blood vessels leak and release fluid into nearby tissues which builds up and causes swelling
244
Wilm's tumour
kidney tumour.
| composed of 3 cellular types: stromal, epithelial and blastemic.
245
blastemic cells
undifferentiated, may have partly changed into stromal or epithelial
246
2 types of wilms tumours
sporadic - no known genetic issues
| inherited - rare but can be inherited in autosomal dominant fashion
247
genetic abnormalities associated with wilms tumour
aniridia - loss of iris
hemihypertrophy - body asymmetry
hypospadias - opening of penis underneath rather than tip
genitourinary malformations
248
Remission and maintenance phase of leukaemia chemo
2-3yrs
| Drugs: methotrexate, vincristine, dexamethasone, mercaptopurine
249
How can chemo meds work?
- inhibit synthesis of nucleotides in DNA +/or RNA
- altering base pairing of DNA/RNA
- inhibiting enzymes
- directly affecting DNA
250
alkylating agents
form covalent bonds with DNA and stop replication
251
antimetabolites
block one or more metabolic pathways
252
cytotoxic antibiotics
prevent cell division
253
plant derivatives in chemo
affect how spindle forms in mitosis
254
Induction phase of leukaemia chemo
4-6wks
Obj: eradicate 99% of leukaemic blasts
Drugs used: dexamethasone, vincristine, asparaginase, daunorubicin
255
Consolidation phase of leukaemia chemo
4-12wks
Obj: eradicate residual leukaemic blasts and reduce risk of bone marrow and CNS relapse
Drugs: vincristine, dexamethasone, thiopurine, methotrexate
256
Delayed intensification phase of leukaemia chemo
8-12wks
Obj: reduces relapse risk
Drugs: methotrexate, vincristine, dexamethasone, doxorubicin, asparaginase, cyclophosphamide, cytarabine, thioguanine
257
Remission and maintenance phase of leukaemia chemo
2-3yrs
| Drugs: methotrexate, vincristine, dexamethasone, mercaptopurine
258
graft vs host disease
cells from body and transplant can attack each other - would have to take immunosuppressants for life
259
astrocytomas - where and what from?
found throughout brain, slow growing.
arise from glial astrocyte cells.
Cerebellar or supratentorial
260
medullablastoma - what from and movement?
arise from primitive neuro-epithelial cells
| metastases along CSF pathway
261
craniopharyngioma - where and what from?
midline tumour usually around pituitary gland
| formed from epithelial cells and cysts
262
brain stem tumours - what do they start from?
arise from primitive glial cells
263
Digestive system blood supply
delivered via mesentric artery but returned by hepatic portal vein into liver rather than general circulation. This is so sugars can be stored in liver as glycogen.
264
Where does most dug metabolism occur?
liver
265
Where are cytochrome P450 enzymes kept?
smooth ER
266
What do cytochrome P450 enzymes do?
metabolise unwanted substances into a from easier to excrete in urine
267
foods that are CYP450 inhibitors
grapefruit + cranberry juice, watercress, gingko bilboa, ginseng
268
Phase ll reactions
attach molecule to the unwanted substance, making it more water soluble and easier for kidneys to excrete
269
enterohepatic recirculation
bile salts are recycled so some drugs can reappear in circulation along with bile, giving them a longer half life (e.g. morphine and rifampicin)
270
4 ways that drugs can cause side effects
1) tipping balance too far
2) hitting unwanted target - might hit receptors causing another effect e.g. salbutamol binds to receptor in heart causing tachycardia
3) autoimmune reactions
4) drugs that are intrinsically hazardous - some drugs work by inflicting damage on rapidly dividing cells so may affect healthy cells
271
Therapeutic index
minimum effect concentration / maximum safe concentration
272
effect of immature liver on drugs metabolism
metabolises faster so cannot generalise rate of drug metabolism in younger children
273
Which drug is prescribed based on race?
ACE inhibitors
274
metabolism definition
conversion of one chemical entity to another
275
foods that are CYP450 inducers
leafy greens, cigarettes, alcohol, st johns wart, valerian, gingko bilboa
276
foods that are CYP450 inhibitors
grapefruit + cranberry juice, watercress, gingko bilboa, ginseng
277
Who is at greatest risk following paracetamol overdose?
those with liver damage
278
factors affecting metabolism
age - reduced first pass metabolism, reduced hepatocytes and enzymes
disease - liver disease means reduced hepatocytes, reduced hepatic blood flow
279
glomerular filtration in excretion
glomerular capillaries allow drugs to diffuse into glomerular filtrate unless too big or if they are bound
280
diffusion across renal tubule - drug excretion
as filtrate transverses tubule, water is reabsorbed.
| Lipophilic drugs are readily reabsorbed so excreted slowly. Highly polar drugs remain in tubule
281
active tubular secretion - drug excretion
drug molecules transferred to the tubular lumen by two independent, non selective carrier systems. carriers can reduce plasma concentration of some drugs to almost 0.
282
extrinsic receptors
outside circulatory system and respond more to environmental changes
283
factors affecting excretion of drugs
disease - reduced renal blood flow
| age - renal function reduced as you get older
284
how does sympathetic system raise HR?
stimulates adrenergic receptors
285
how does parasympathetic system lower HR?
via vagus nerve
286
how do heart contractions occur?
SA node releases signals - sent to ventricles via AV node. AV node delays impulses on way to ventricles so sequence can occur in stages and peak cardiac output can be achieved. From AV node, impulse travels down bundle of His, separating into 2 branches towards ventricles. Faster down left - diff in speed allows them to contract together due to thicker myocardium around left ventricle. Branches end in purkinje fibres + then myocytes contract causing ventricular contraction.
287
pulse pressure
difference between systolic and diastolic BPs
288
mean arterial pressure definition
average pressure in arterial system during ventricular contraction and relaxation
289
Mean arterial pressure calculation (MAP)
MAP = cardiac output (CO) x peripheral vascular resistance (PVR)
290
Cushing's triad
late sign of raised ICP:
- decreased HR
- increased BP
- reduced RR and change in pattern
291
extrinsic receptors
outside circulatory system and respond more to environmental changes
292
effect of different hormones on BP
ADH - increases BP via vasoconstriction
Renin - increases BP by converting angiotensin
Angiotensin ll - increases BP via vasoconstriction, aldosterone release
Aldosterone - increases BP by increasing retention of sodium and water in kidneys
293
list some common congenital heart defects
patent ductus arteriosus
patent foramen ovale
fallot's tetralogy - combo of 4 defects
atrioventricular septal defect
294
5 types of intracranial haemmorhage
```
subdural - below dura mater
epidural - between skull and dural membrane
subarachnoid - within subarachnoid space
intracerebral
intraventricular
```
295
hydrocephalus
excessive accumulation of CSF in brain due to overproduction, flow obstruction or decreased absorption.
296
Layers of skull
- scalp
- bone
- dura mater
- arachnoid mater
- subarachnoid space
- pia mater
- brain tissue
297
basic flow of CSF
produced by choroid plexuses
flows through ventricles into subarachnoid space
absorbed into dural venous sinuses via arachnoid villi
298
management of hydrocephalus
shunt
| control of cardiovascular events
299
Cushing's triad
late sign of raised ICP:
- decreased HR
- increased BP
- reduced RR and change in pattern
300
brain herniation
brain moves outside of skull or across into a structure within the skull
301
supratentorial herniation
displacement of cerebrum
302
infratentorial herniation
displacement of cerebellum
303
focal mass effect of brain herniation
intracranial bleeds
tumours and abcesses
local oedema
304
diffuse mass effect of brain herniation
```
generalised cerebral oedema
cytogenic oedema - within cells
vasogenic oedema
large ischaemic stroke
meningitis
```
305
uncal herniation
uncus slips down, puts pressure on brain stem and oculomotor nerve. Compresses cerebral artery. affects L/R vision, not central.
306
3 main types of spina bifida
myelomeningocele - spinal cord and meninges protrude out of opening in bony vertebrae. Held by sac of skin that pouches out from back. Some have no skin, leaving spine exposed (paralysis).
meningocele - only in meninges - slip into gaps between deformed vertebrae. least common and less symptoms.
spina bifida occulta - most common. tiny deformities, asymptomatic.
307
cingulate herniation
cingulate durus squeezed to opposite part of skull
308
transcalvarial herniation
brain squeezes out of skull through fracture or surgical site
309
upward herniation
cerebellum displaced upwards
310
tonsilar herniation
cerebral tonsils slip down through foramen magnum
| CONING
311
classification of cerebral palsy
spastic - tight/stiff muscles, jerky, hypertonia
dyskinetic - damage to basal ganglia. dystonia (random slow, uncontrolled movements in limbs or trunk) and chorea ( random dance like movements)
ataxic - damage to cerebellum. without order, poor balance and shaky
312
what is cerebral palsy?
damage to brain causing paralysis
313
what is spina bifida?
tissues on spinal cord don't meet, leaving openings of unprotected spine
314
how does spinal cord develop?
ectoderm develops ridge which becomes the neural tube. This becomes the spinal cord, brain and meninges.
315
Two types of ADHD and how it is diagnosed?
1) inattentive - 9 symptoms
2) hyperactive - 9 symptoms
3) both
diagnosed if have 6/9 symptoms for at least 6 months
316
what causes epilepsy?
neurons are synchronously active.
317
what happens during seizure?
cluster of neurons sends out cluster of signals - too much excitation due to glutamate or too little inhibition due to gaba.
318
what is cerebral perfusion pressure and how to calculate?
pressure required to maintain adequate cerebral blood flow:
| CPP = MAP - ICP
319
how to diagnose epilepsy?
brain imaging
| electroencephalogram
320
acceptable cerebral perfusion pressure (CPP)?
above 50-70mmHG
321
role of glutamate
neurotransmitter which opens calcium ion channels (excites AP)
322
role of gaba
neurotransmitter which opens chloride ion channels (this inhibits AP as makes the cell negative)
323
Two types of ADHD and how it is diagnosed?
1) inattentive - 9 symptoms
2) hyperactive - 9 symptoms
3) both
diagnosed if have 6/9 symptoms for at least 6 months
324
how many vertebrae are there and what are they?
33:
- 7 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 4/5 occygeal
325
slipped disc
cartilagenous tissue between vertebrae has bulged out
326
hyperflexion of spine
when the spine is bent forwards exceeding the span of movement that is possible
327
hyperextension of spine
when the spine is extended backwards, eg hit in the jaw and the head is forced backwards
328
Axial injury of spine
when the person lands on their head or their feet and the force on landing travels upwards through the body and the spine, eg diving into swimming pools, catapulted over a car
329
Rotation injury of spine
when the body twists as the person lands
330
spinal dislocation
when ligaments are over-stretched or torn, which allows the spine to move out of line or vertebrae to ‘lock’ over each other.
331
simple fracture
where the fracture leaves the vertebra in place, aligned with the other vertebrae and there are no neurological deficits.
332
compression fracture
where the fracture is caused by an axial injury and hyperflexion
333
wedge compression fracture
a stable fracture but also includes compression of the vertebra, typically this occurs in the neck area
334
teardrop fracture
where a piece of the vertebra breaks away, making the fracture unstable
335
comminuted fracture
where the vertebra shatters into small pieces. This is very unstable and will affect the spinal cord
336
partial spinal cord syndrome
injury to one side of cord , leading o loss of movement of that side of body. Opposite side loses ability to maintain temp, sense pain and touch
337
spinal shock
complete loss of function below level of spinal cord injury. communication between brain and bottom of spinal cord is disrupted.
338
neurogenic shock
severe form of spinal shock, where sympathetic impulses to heart are lost
339
quadriplegia
loss of leg function and partial/total loss of arm function
340
paraplegia
loss of leg function
341
hermiplegia
paralysis of one side of body
342
posterior cord syndrome
some sensory +/or motor function is maintained
343
anterior cord syndrome
some loss of motor function below injury
344
factors affecting excretion in children
reduced GFR, reduced tubular secretion
345
scoliosis
C or S shaped curved spine
346
kyphorosis
exaggerated, abnormally round upper back
347
lordosis
sway back, spine curves in more than normal at lower back
348
when does spina bifida usually form?
day 22 when neural tube closes at each end
349
factors affecting absorption in children
higher gastric pH in neonates, skin less developed so greater surface area, delayed gastric emptying, reflux, reduced muscle blood flow
350
factors affecting distribution in children
increased membrane permeability in preterms, reduced albumin so more free drug, greater water content
351
factors affecting metabolism in children
different metabolites, enzyme systems still developing up to 10 years, excess bilirubin competes
352
factors affecting excretion in children
reduced GFR, reduced tubular secretion
353
behavioural drug-drug interactions
alters patients behaviour to modify compliance with another drug
354
pharmaceutic polypharmacy
formulation of one drug is altered by another before administration
355
distributive shock
anaphylactic
neurogenic
septic
356
pharmacodynamic polypharmacy
interacting drugs have either additive or opposite effects
357
pharmacogenomics
studies to identify genes involved in determining responsiveness to a given drug and to distinguish who will respond to specific drugs
358
signs of shock
increased HR, CRT and RR
| decreased BP, spO2, conscious level, urine output and pH level
359
shock definition
acute circulatory crisis caused by any reduction in blood flow, marked by tachycardia and hypotension
360
3 stages of shock
1) compensatory - arterial pressure and tissue perfusion reduced, compensatory mechanisms activated to maintain perfusion to the heart and brain
2) progressive stage - begins as compensatory mechanisms fail to maintain CO and tissues become hypoxic due to poor perfusion
3) irreversible stage - as shock progresses, permanent organ damage occurs as compensatory mechanisms can no longer maintain CO
361
why is vitamin K given at birth and then at 7 days?
to help with blood clotting
362
cardiogenic shock
inadequate pump or increased demand on heart
363
distributive shock
anaphylactic
neurogenic
septic
364
Embryological development of heart
day 20 - endothelial tubes begin to fuse
day 22 - heart starts pumping
day 24 - heart continues to elongate and starts to bend
day 28 - bending continues as ventricle moves caudally and atrium moves cranially
day 35 - bending is complete
365
pathophysiology of heart failure
trigger event reduces ability of myocardium to contract --> reduction in cardiac output --> sympathetic nervous system responds or RAA system is activated
366
effect of RAA system being activated in heart failure
high levels leads to further myocardial injury
367
how does sympathetic system respond to heart failure?
releases noradrenaline to maintain MAP and organ perfusion
368
effects of underproduction of stress hormones
hypoglycaemia, weakness, hypotension, PTSD like effects
369
signs of heart failure in adolescents
```
fatigue + exercise intolerance
SOB and tachypnoea
low BP
abdo pain
oliguria
pitting oedema
```
370
staging of heart failure
1) aymptomatic
2) mild tachypnoea or diaphoresis with feeding
3) mared tachypnoea or diaphoresis with feeding. prolonged feeding times with growth failure, mearked dyspnoea or exertion in older children.
4) tachypnoea, recession, grunting ot diaphoresis at rest
371
investigations for heart failure
```
CXR
ECG
echocardiography
cardiac catheterisation
exercise stress test
```
372
medications used in heart failure
ACE inhibitors, B blockers, inotropes, vasodilators, diuretics.
373
Stress response - alarm phase
occurs in seconds, lasts minutes
fight or flight response
- increased O2 and energy availability
- divert blood to required tissues
- enhance senses
- immune changes
- activate sympathetic nervous system
374
stress response - resistance phase
cope with ongoing demands
lasts for hrs/days/yrs
mainly hormonal, maintains body in survival mode
growth hormone - increased lipolysis to free fatty acid as energy source, increased glucose availability
thyroid hormone - increased glucose breakdown to produce ATP
cortisol - increased glucose availability, maintain vascular and renal functions, suppresses immune system, feedsback to CNS
375
effects of overproduction of stress hormones
hyperglycaemia, tissue wastage, insulin resistance, cardiovascular changes, anxiety, psychosis, immunosuppression
376
effects of underproduction of stress hormones
hypoglycaemia, weakness, hypotension, PTSD like effects
377
medication for type 2 diabetes
sulfonylureas which stimulate beta cells to produce more insulin
378
alpha islets of langerhans
secrete glucagon
379
descending pain pathway
signal from periaqueductal grey matter travels to nucleus raphe magnus and synapses with 2nd neuron. Travels to dorsal horn of spinal cord. This neuron should control communication between 1st and 2nd order neuron to help control pain signals.
380
delta islets of langerhans
secrete somatostatin produced by other endocrine cells
381
normoglycaemia cycle
increased blood glucose --> pancreas releases insulin which stimulates glycogen formation in liver and stimulates glucose uptakes by cells --> blood glucose falls to normal range
382
symptoms of diabetes
hyperglycaemia, hypoglycaemia, polyuria, polydispia, glycosuria, pruritis
383
type 1 diabetes
irreversible autoimmune destruction of the islets of langerhans - body cannot produce insulin
384
type 2 diabetes
secondary decline in insulin secretions by islets of langerhans
can produce insulin but no enough or it doesn't work properly due to a resistance to glucose
385
medication for type 2 diabetes
sulfonylureas which stimulate beta cells to produce more insulin
386
ascending pain pathway
Cell damage leads to prostaglandin release. Sensory nerve fibres carry this signal to the dorsal horn of the spinal cord (1st order neuron). Relayed to 2nd order neuron which carries the signal to the spinothalamic tract and ascends through the spinal cord, brain stem and terminates in the thalamus (relay station). 2nd order synapses with 3rd order which relays to cortex that receives pain.
387
descending pain pathway
signal from periaqueductal grey matter travels to nucleus raphe magnus and synapses with 2nd neuron. Travels to dorsal horn of spinal cord. This neuron should control communication between 1st and 2nd order neuron to help control pain signals.
388
Af fibers pain
fast, localised sharp pain
389
C fibers pain
slow, poorly located pain
390
minimum length of chronic pain
3 months
391
glial cells
non neuron cells which protect neurons
392
role of glial cells in pain
when exposed to neurotransmitters, glial cells are activated and produce chemicals which communicate with afferent pain pathway - stimulates more neurotransmitters which causes more pain (positive feedback cycle)
393
embryology of brain
17 days - flat 3 layered embryo
20 days - neural folds to form neural plate
22 days - neural folds close to form neural tube
Week 4 - primary vesicles develop into fore, mid and hind brain
Weeks 5-11 - secondary vesicles develop into diff parts of brain. (week 5) - 2 major flexuses form, causing telencephalon and diencephalon to angle towards brain stem
Week 13 - cerebral hemispheres develop and grow to enclose diencephalon and rostral brain stem
394
role of cerebrum
speech, thoughts, emotion, muscle function
395
role of thalamus
sensory relay station
396
role of epithalamus
endocrine processes
397
role of hypothalamus
controls hormone release
398
role of cerebellum
physical movement
399
role of hippocampus
consolidates short term memory
400
role of amygdala
emotions
401
embryology of brain
17 days - flat 3 layered embryo
20 days - neural folds to form neural plate
22 days - neural folds close to form neural tube
Week 4 - primary vesicles develop into fore, mid and hind brain
Weeks 5-11 - secondary vesicles develop into diff parts of brain. (week 5) - 2 major flexuses form, causing telencephalon and diencephalon to angle towards brain stem
Week 13 - cerebral hemispheres develop and grow to enclose diencephalon and rostral brain stem
402
neurocranium
protective case of skull
403
viscerocranium
facial skeleton
404
hepatic encephalopathy
loss of brain function as result of failure in the removal of toxins from blood due to liver damage
405
when does posterior fontanelle close?
4-6 weeks old
406
growth of brain up to 10 years old
doubles by 1 year
75% by 2
90% by 6
100% by 10
407
ionotropic
neurotransmitter made of proteins
408
role of occipital lobe
vision
409
combination of neurotransmitters with receptors (dopamine, adrenaline, histamine and opioid)
dopamine - at least 5 different receptors
adrenaline - alpha and beta receptors
histamine - H1, H2 or H3
opioid - Mu, delta, kappa and ORL1 receptors, involved with pain due to tissue damage
410
hypoxic-ischaemic injury
occurs during prenatal, intrapartum or postpartum period where adequate cerebral blood flow is prevented from providing oxygen to the brain.
moderate decrease in cerebral perfusion triggers cerebral arteries to redistribute blood to posterior circulation to maintain adequate perfusion to brain stem, basal ganglia and cerebellum. damage occurs in cerebral cortex and hemispheres.
411
effect of angiotensin converting enzyme inhibitor
blood pressure will fall due to vasodilation
412
What term indicates the disability caused by a fracture occurring at L2?
paraplegia
413
Where are the stem cells that can become all types of leukaemia produced?
red bone marrow
414
role of parietal lobe
sensory perception and integration
415
role of temporal lobe
cognitive functions and control of voluntary movement or activity
416
role of occipital lobe
vision
417
where does the coronary vein drain into?
into the great cardiac vein and through the coronary sinus into the right atrium.
418
why can insulin not be given orally?
it is a protein so broken down by digestive enzymes (protease)
419
effect of angiotensin converting enzyme inhibitor
blood pressure will fall due to vasodilation
420
what are statins used for?
to reduce cholesterol levels
421
Where are the stem cells that can become all types of leukaemia produced?
red bone marrow
422
What kind of polysaccharide is the main food source of energy for humans?
starch
423
ACE inhibitors such as captopril can accidently bind to and block kininase enzymes in the bronchioles – how might this cause the side-effect of a dry cough?
levels of bradykinin can build up and irritate the lining of the lungs
424
How may calcium channel blockers such as verapamil cause constipation?
inhibit contraction of smooth muscle - reduce peristalsis
425
how does drug get from digestive system to circulation?
gut --> hepatic portal vein --> liver --> hepatic vein into circulatory system
426
why can insulin not be given orally?
broken down by digestive enzymes
427
transposition of the great arteries
where two major vessels leaving the heart do so from the wrong ventricles
428
what are statins used for?
to reduce cholesterol levels
429
What lipid is the raw material for steroid hormones?
cholesterol
430
What kind of polysaccharide is the main food source of energy for humans?
starch
431
Explain the term sympathomimetic.
has an adrenergic effect
432
What type of natural chemical messenger would bind to nicotinic and muscarinic receptors?
acetylcholine
