CR EOYS1 Flashcards
Decsribe the structure of NOSs xx
NOS: oxidoreductase homodimer enzymes:
- Oxygenase domain: binding for NADPH, FMN & FAD
- Reductase domain: binding for BH4, heme and L’arginine (substrate
- Calmodulin binding site: in between reductase and oxidase domains
What happens to NOS if there is / isn’t BH4 present?
BH4 present: causes dimerisation and proper catalytic activity for NO formation
BH4 absence: causes monomer, becomes a superoxide
For the formation of NO using NOS, what substrates are essential? [3]
Which co-factors are essential? [5]
For the formation of NO using NOS, what substrates are essential? [3]
- L-arginine
- O2
- NADPH
Which co-factors are essential? [5]
- FAD
- FMN
- BH4
- haem
- calmodulin.
OXYGEN is essential for the synthesis. Because of the oxygen requirement, NO synthesis is inhibited in hypoxic tissue
Explain MoA of endothelial NO synthase creating NO
- Normally: eNOS associates with Caveolin 1 in caveolae (invaginations of plasma membrane) this inhibits calmodulin complex (CaM) binding to eNOS
- Shear stress promotes wall stretching, which promotes the dissociation of eNOS from caveolae
- This allows eNOS release into the cytoplasm and its activation (through binding of a Ca2+/ calmodulin (CaM) complex)
- M2-muscarinic acetylcholine receptor activation or other stimulation initiates an influx of Ca2+ that binds to calmodulin.
- eNOS dissociates from Cav1 and then combines to Ca/CaM.
- eNOS is activated leading to synthesis of NO.
[] shear stress favors the activation of eNOS by releasing endothelium-dependent agonists.
What are they? [4]
Increased shear stress favors the activation of eNOS by releasing endothelium-dependent agonists.
Agonists stimulated NO formation:
* Acetylcholine (M3muscarinic)
* Bradykinin
* Substance-P
* Adenosine
What can endothelial dysfunction be caused by? [4]
Consumptive processes that transform bioavailable NO into other species:
- Reactive oxygen species such as -O2 reacts readily with NO forming peroxynitrite (ONOO−)
- Uncoupling of NOS: BH4 insufficiency results in uncoupled NOS, which produces superoxide anions instead of NO
Deficiencies in production of NO in the endothelium:
- Reduced bioavailability of l-arginine o
- Presence of its inhibitor, asymmetric dimethyl-l-arginine (ADMA)
Describe the pathophysiology behind acute bronchitis (e.g. caused by respiratory synctial virus)
Epithelial cells: 1st line of defence
RSV: binds and invades mucosal lining via epithelial cells
Epithelial cells switch on immune response after recognised through Toll-like receptor (TLR)-3 and retinoic acid-inducible gene (RIG)-I-like receptors
Cellular infection triggers the release of early inflammatory mediators (e.g.interferons (IFNs) and tumour necrosis factor (TNF)-α) and chemokines (e.g.CXCL8 and CXCL11).
A) Innate: Macrophages and Neutrophils, e.g. PMN polymorphonuclear leukocytes cells recruited PMNs)
B) Acquired: Dendritic cell, triggering B and T cells: CD4, CD8 and primed T cells
Name the signs of pneumonia [4]
Name a complication that pneuomonia a risk factor for !!
Signs:
- Tachypnoea
- Tachycardia
- Hypoxia
- Hypotension
- Fever
- Confusion
Can lead to sepsis
How do you diagnose acute bronchitis?
Diagnosis by exclusion:
- Cough >3 weeks
- If signs of consolidation (on CXR), airway obstruction, fever, increase RR, increase HR: NOT acute bronchitis
- If no: is there currently an outbreak of influenza pertusis (whooping cough)?
- If no: Acute bronchitis
How does hypertension damage the heart?
What effect does HTN have on SVR? [1]
State the cardiac remodelling that initially occurs because of HTN [1]
State the effect on heart performance of chronic HTN [2]
HTN leads to increased systemic vascular resistance compared to normal in HTN.
Initially leads to HTN leads toleft ventricular hypertrophy (initially protective, but long term is damaging) to overcome increased afterload:
Chronic HTN leads to diastolic and (eventually) systolic dysfunction: there is less space to in ventricle to pump blood out. This leads to dilated cardiomyopathy/congestive heart failure
what can left ventricular hypertrophy lead to? [3]
Dilated cardiomyopathy/congestive heart failure
If increased cardiac muscle is not well perfused myocardial ischaemia and myocardial infarction can follow.
Conducting system also impacted: increasing risk arrythmias
What are the BP ranges for isolated diastolic HTN (BP)? [1]
Abstract. In various guidelines, isolated diastolic hypertension is defined as diastolic blood pressure >80 or >90mmHg in individuals with normal systolic blood pressure.
Why does obesity increase BP? [3]
- increased oxidative stress damages endothelium of BV: stiffer
- increased RAAS system
- increases sympathetic system
which all influence CVD and CKD, which themselves contribute to BP
What specifically about obesity causes increase in HTN? [1]
High leptin levels increase activity of RAAS and sympathetic NS
Anti-hypertensives:
Which of the following class of drug does indapamide fall into?
ACE inhibitors:
Angiotensin-II receptor antagonists
Calcium-channel blocker
Diuretics
Beta-blockers
Which of the following class of drug does indapamide fall into?
ACE inhibitors:
Angiotensin-II receptor antagonists
Calcium-channel blocker
Diuretics thiazide-like diuretic
Beta-blockers
Which of the following class of drug does enalapril fall into?
ACE inhibitors:
Angiotensin-II receptor antagonists
Calcium-channel blocker
Diuretics
Beta-blockers
Which of the following class of drug does enalapril fall into?
ACE inhibitors:
Angiotensin-II receptor antagonists
Calcium-channel blocker
Diuretics
Beta-blockers
Which of the following class of drug does losartan fall into?
ACE inhibitors:
Angiotensin-II receptor antagonists
Calcium-channel blocker
Diuretics
Beta-blockers
Which of the following class of drug does losartan fall into?
ACE inhibitors:
Angiotensin-II receptor antagonists
Calcium-channel blocker
Diuretics
Beta-blockers
Which of the following would you use to deliver 24 – 30% O2 (maximum flow rate of 4L/min) for mild hypoxia?
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would you use to deliver 24 – 30% O2 (maximum flow rate of 4L/min) for mild hypoxia?
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would you use to deliver for patients with chronic obstructive pulmonary disease (COPD) due to the risk of type 2 respiratory failure.
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would you use to deliver for patients with chronic obstructive pulmonary disease (COPD) due to the risk of type 2 respiratory failure.
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would you use to deliver approximately 70% O2 when used with a 15L oxygen flow rate.
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would you use to deliver approximately 70% O2 when used with a 15L oxygen flow rate.
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
7Which of the following would you use to deliver 30 – 40% O2 (flow rate 5-10 L/min)
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would you use to deliver 30 – 40% O2 (flow rate 5-10 L/min)
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would used to treat patients with a significant degree of hypoxia (moderate to severe).
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
Which of the following would used to treat patients with a significant degree of hypoxia (moderate to severe).
Nasal cannulae
Simple face mask
Non-rebreather mask
Venturi mask
What mmHg would systolic [1] and diastolic [1] blood pressure indicate have pneumonia? [2]
- SBP < 90
- DBP < 60
The vocal cords attach posteriorly to which of the following?
Cricoid cartilage
Cuneiform cartilage
Epiglottis
Arytenoid cartilage
Thyroid cartilage
The vocal cords attach posteriorly to which of the following?
Cricoid cartilage
Cuneiform cartilage
Epiglottis
Arytenoid cartilages
Thyroid cartilage
What happens to the levels of paO2 in arterial blood during high levels of exercise?
At high levelss of exercise the paO2 in the arterial blood declines slightly
Which of the following is the correct name for the piece of equipment shown in the image?
Nasal cannulae
Venturi mask
Nasopharyngeal airway
Reservoir mask
Hudson mask
Which of the following is the correct name for the piece of equipment shown in the image?
Nasal cannulae
Venturi mask
Nasopharyngeal airway
Reservoir mask
Hudson mask
A 36-year-old Norwegian female presents with a 4-month history of gradually progressive shortness of breath, a non-productive cough and fatigue. She also reports painful red lesions on her shins. She has no significant medical/surgical history and is on no regular medications. She has no family history of note. She is a non-smoker and non-drinker. She is married and works as a classroom assistant. Her review of systems is otherwise unremarkable.
She is afebrile and her vital signs are within normal limits. Respiratory examination is normal. On inspection of the lower limbs, there are tender erythematous nodules on the anterior aspects of her lower legs bilaterally.
Given the most likely underlying diagnosis, what is the most likely cause of the skin lesions on her lower limbs?
Necrobiosis lipoidica
Pyoderma gangrenosum
Acanthosis nigricans
Erythema multiforme
Erythema nodosum
Erythema nodosum
The most likely underlying diagnosis is sarcoidosis, given this patient’s Scandinavian ancestry, age, female gender and constellation of non-specific symptoms and signs. Erythema nodosum (painful, blue-red nodules most commonly affecting the shins) is associated with sarcoidosis. Other causes of erythema nodosum include TB, streptococci and certain drugs (eg. sulfonamides, dapsone, COCP).
Describe the 4 classes of haemorrhagic shock
x
What are the axillary lymph nodes? [3]
Where do they drain lymph from? [3]
Ddescribe their path to to L / R venous angle [2]
Humeral lymph nodes drain from upper limb
Pectoral lymph nodes drain from anterior chest wall (majority drains into here)
Subscapular lymph nodes drain from posterior chest wall (rotator cuffs etc)
Together: go to central –> apical –> supraclavicular –> left / right venous angle
Label the vert. layers of A-D
The laryngeal prominence occurs at which vertebral level
C3
C4
C5
C6
C7
The laryngeal prominence occurs at which vertebral level
C3
C4
C5
C6
C7
