Miscellaneous Flashcards
1
Q
What does DNA stand for?
A
Deoxyribonucleic acid
2
Q
What are the four nitrogenous bases in DNA?
A
- Thymine (T) * Cytosine (C) * Adenine (A) * Guanine (G)
3
Q
Which nitrogenous bases are pyrimidines?
A
- Thymine (T) * Cytosine (C)
4
Q
Which nitrogenous bases are purines?
A
- Adenine (A) * Guanine (G)
5
Q
What is the human karyotype for females?
A
46XX
6
Q
What is the human karyotype for males?
A
46XY
7
Q
What proteins compact DNA when it is not being transcribed?
A
Histones
8
Q
What is the role of topoisomerase enzymes?
A
They cause relaxation of the ‘supercoiling’ compaction process to allow transcription.
9
Q
What percentage of DNA is thought to be non-coding material?
A
More than 98%
10
Q
What is the purpose of transcription?
A
To copy a single strand of DNA genetic material into a single strand of complementary RNA.
11
Q
What enzyme executes the transcription process?
A
RNA polymerase
12
Q
Where does translation occur?
A
In the cytoplasm
13
Q
What are the roles of transfer RNA (tRNA)?
A
Traffic amino acids to the ribosome for the translation process.
14
Q
What is a gene?
A
A segment of DNA that encodes for a functional protein.
15
Q
What are introns?
A
Non-coding material that does not undergo translation.
16
Q
What are exons?
A
Coding sequences that are joined together after introns are removed during RNA splicing.
17
Q
What is an allele?
A
A variant form of a gene.
18
Q
What is a point mutation?
A
A change in a single base pair in the DNA sequence.
19
Q
What is a frameshift mutation?
A
A mutation that changes the reading frame of the coding sequence.
20
Q
What are the three basic stages of the human cell cycle?
A
- Interphase * Mitosis * Cytokinesis
21
Q
What happens during the G1 phase of the cell cycle?
A
Cell increases in size and produces proteins to prepare for DNA replication.
22
Q
What occurs during the M phase of the cell cycle?
A
Cell division occurs.
23
Q
What are checkpoints in the cell cycle?
A
Critical stages that help to regulate cell division and avoid abnormal cell production.
24
Q
What is non-disjunction?
A
Failure of chromosomal separation during meiosis, leading to reproductive cells with abnormal chromosome numbers.
25
What is uniparental disomy?
Inheritance of both chromosomes from a single parent.
26
What is an example of an autosomal dominant disease?
Huntington's disease
27
What is the expected inheritance pattern for autosomal recessive diseases?
Requires inheritance of a single mutated allele from both parents.
28
What type of inheritance requires a single mutated allele from the mother for transmission to sons?
X-linked recessive inheritance
29
What is mitochondrial inheritance?
Inheritance of genetic material through the mitochondria, only from the mother.
30
What does imprinting refer to in genetics?
Parental imprinting of a gene that modifies expression of that specific allele.
31
What is mosaicism?
A genetic mutation that occurs early during development within progenitor cells affecting specific tissues.
32
What are expansion diseases?
Genetic disorders arising from increasing trinucleotide repeating patterns within DNA coding regions.
33
What is anticipation in genetics?
The expected increased number of repeats causing younger and more severe disease.
34
What does anticipation refer to in genetics?
Expected increased number of repeats causing younger and more severe disease
## Footnote
Often associated with paternal inheritance.
35
What is variable penetrance?
Relates to an intermediate number of repeats
## Footnote
Indicates that not all individuals with a genetic mutation will express the associated phenotype.
36
What is aneuploidy?
Abnormal numbers of chromosomes
37
What is monosomy?
A form of aneuploidy that generally causes more severe disease than trisomy
38
What are Klinefelter's and Turner's Syndromes?
Sex chromosome aneuploidy conditions
## Footnote
Klinefelter's is 47XXY and Turner's is 45X.
39
What is the hierarchy of evidence in clinical study design?
Shows increasing levels of evidence and reliability based on participant number and bias reduction
40
What is a randomized controlled trial (RCT)?
A study design where participants are randomly allocated to intervention or control groups
41
What is a meta-analysis?
Combines data from multiple clinical trials to establish definitive outcomes
42
What is selection bias?
Occurs when subjects chosen do not adequately represent the entire population
43
What does Phase 1 of RCTs focus on?
Assessing pharmacokinetics, metabolism, and dosing with very limited participants
44
What is the purpose of Phase 2 in clinical trials?
Establishing doses required for a positive effect and identifying the minimum effective dose
45
What is the main aim of Phase 3 in clinical trials?
Conducting a complete randomized controlled trial often with large sample sizes
46
What is the purpose of Phase 4 in clinical trials?
Post-marketing surveillance to identify long-term adverse effects
47
What is univariate analysis?
Investigates parameters of single populations, often used prior to intervention
48
What does bivariate analysis compare?
Two populations, often before and after an intervention
49
What is the null hypothesis?
A presumption that there is no correlation between two sets of data or intervention
50
What does a p-value <0.05 indicate?
Statistical significance in clinical trials
51
What is relative risk?
Comparison of risk in the intervention group compared to the control group
52
What is absolute risk reduction (ARR)?
The actual difference in risk between the control and intervention groups
53
What does odds ratio compare?
The number of positive outcomes in the intervention group to the number of negative outcomes in the control group
54
What is a hazard ratio (HR)?
The rate of difference between two groups
55
What are Kaplan-Meier curves used for?
Analyzing survival rates of control and intervention groups over time
56
What is sensitivity in a clinical test?
The proportion of affected people that correctly test positive
57
What is specificity in a clinical test?
The proportion of unaffected people that correctly test negative
58
What is positive predictive value (PPV)?
The chance of being affected with a positive test result
59
What is negative predictive value (NPV)?
The chance of being unaffected with a negative test result
60
What does likelihood ratio (LR) assess?
The chance that a positive or negative outcome will occur with an affected person compared to a healthy subject
61
What do predictive values allow?
The interpretation of a test result into the chance of a person being truly affected/unaffected by a condition being tested for
62
What is Positive Predictive Value (PPV)?
The chance of being affected with a positive test result
63
What is Negative Predictive Value (NPV)?
The chance of being unaffected with a negative test result
64
What do Likelihood Ratios (LR) compare?
Affected and healthy people
65
What does the Positive Likelihood Ratio (LR+) formula consist of?
Sensitivity + (1 - Specificity)
66
What does the Negative Likelihood Ratio (LR-) formula consist of?
(1 - Sensitivity) + Specificity
67
What is required to calculate sensitivity, specificity, PPV, and NPV?
Data sets
68
What is the prevalence of a condition in the example?
5 in 1,000
69
What is the total population used for calculations in the example?
10,000 people
70
What is the formula for Sensitivity?
A / (A + C)
71
What is the formula for Specificity?
D / (B + D)
72
What does PPV stand for?
Positive Predictive Value
73
What does NPV stand for?
Negative Predictive Value
74
What is the formula for PPV?
A / (A + B)
75
What is the formula for NPV?
D / (C + D)
76
What is the significance of high sensitivity in a screening test?
Most people with a negative test are truly unaffected
77
What are key values of a screening test?
* Period prior to symptoms that the test can identify disease
* Intervention during the pre-symptomatic period must change the natural history of disease
* Easy to deliver and cost-effective
* High sensitivity (and specificity if possible)
78
What does pharmacokinetics refer to?
The effect of the body on the drug
79
What is the gold standard for absorption of medications?
Intravenous medications with 100% bioavailability
80
What factors affect the bioavailability of oral medications?
* Water vs lipid solubility
* p-glycoprotein activity
* First pass metabolism
81
What is the formula for Volume of Distribution (Vd)?
Vd = Ab / Cp
82
What is the significance of loading doses?
Used to achieve rapid steady state concentration
83
What is Zero Order Kinetics?
Linear slope of excretion due to saturable metabolism
84
What is First Order Kinetics?
Classical decaying half-life metabolism dependent on drug concentration
85
What two key stages does hepatic metabolism involve?
* Oxidation
* Glucuronidation and acetylation
86
What does clearance refer to in pharmacology?
The volume of plasma of drug cleared per minute
87
What is the formula for clearance (CI)?
CI (L/min) = 0.693 x Vd (L) / t1/2 (min)
88
What is the therapeutic index?
The difference in drug concentration between efficacy and toxicity
89
What is the effect of urinary pH on drug excretion?
Acidic urine increases alkali drug excretion but reduces acidic drug excretion
90
What does pharmacodynamics refer to?
The effect of the drug on the body
91
What is an agonist?
Enhances the action of the target receptor
92
What is a full agonist?
Elicits maximal response
93
What is a partial agonist?
Elicits partial response
94
What is a competitive antagonist?
Binds to the receptor at the same site as the agonist
95
What is the difference between efficacy and potency?
* Efficacy: maximum efficacy (Emax)
* Potency: amount of drug required to reach 50% of the efficacy (ED50)
96
What is the significance of drug dosing in relation to therapeutic window?
Drugs with a narrow therapeutic window require more frequent dosing and monitoring
97
What is the purpose of monitoring drug levels?
To avoid adverse effects, especially for drugs with a narrow therapeutic index
98
What is the formula for calculating the Index?
Index = LDtt + EDyt
99
Why is drug monitoring important?
Adverse effects can sometimes be avoided by monitoring drug levels
100
Which drugs should be monitored closely due to their narrow therapeutic index?
* Gentamicin
* Perhexiline
* Digoxin
101
When should drug levels be taken?
Following establishment of the steady state concentration
102
What is the purpose of taking trough levels for drugs like digoxin?
To monitor drug toxicity
103
What are the two major types of adverse drug reactions?
* Type A
* Type B
104
What characterizes Type A adverse drug reactions?
Related to the pharmacodynamic action of the drug, dose-dependent, predictable
105
Provide an example of a Type A adverse drug reaction.
Bleeding with warfarin
106
What characterizes Type B adverse drug reactions?
Unrelated to the pharmacodynamic action of the drug, not dose-dependent, unpredictable
107
Provide an example of a Type B adverse drug reaction.
Stevens-Johnson Syndrome
108
What are the characteristics of Neuroleptic Malignant Syndrome (NMS)?
* High fever
* Muscle rigidity
* Autonomic instability
* Cognitive changes
109
What causes Neuroleptic Malignant Syndrome?
Overwhelming blockade of D2-receptors
110
Which drugs predispose to Neuroleptic Malignant Syndrome?
* Antipsychotics (e.g., risperidone)
* Antiemetics (e.g., metoclopramide, ondansetron)
* Antihistamines (e.g., promethazine)
111
What is the treatment for Neuroleptic Malignant Syndrome?
* Supportive care
* Drug cessation
* Aggressive cooling
112
What characterizes Serotonin Syndrome?
* High fever
* Sweating
* Dilated pupils
* Diarrhoea
* Hyperreflexia
* Myoclonus
* Tremor
* Seizures
* Rhabdomyolysis
113
What causes Serotonin Syndrome?
Overwhelming serotonin-receptor agonism
114
Which drugs predispose to Serotonin Syndrome?
* SSRIs
* SNRIs
* Tricyclic antidepressants
* Tramadol
* Metoclopramide
* Ondansetron
* St John's Wort
115
What is the treatment for Serotonin Syndrome?
* Supportive care
* Drug cessation
* Seizure management
116
What is the safest medication for treating Serotonin Syndrome?
Cyproheptadine
117
What cardiovascular changes occur during pregnancy?
* Increased plasma volume
* Increased heart rate
* Increased cardiac output
* Decrease in systemic vascular resistance
118
What are high-risk cardiac conditions in pregnancy?
* Left-sided obstructive valve defects (e.g., mitral stenosis, aortic stenosis)
* Pulmonary arterial hypertension
* Preexisting left ventricular systolic dysfunction
119
What is peripartum cardiomyopathy?
A rare condition affecting <0.1% of pregnancies worldwide
120
What are the risk factors for peripartum cardiomyopathy?
* Older females
* Gestational hypertension
* Pre-eclampsia
121
What does transthoracic echocardiography reveal in peripartum cardiomyopathy?
A dilated, globally hypokinetic left ventricle with reduced ejection fraction
122
What is the management for anticoagulation during pregnancy?
* Unfractionated and low molecular weight heparins are safe
* Warfarin is avoided in the first trimester and during breastfeeding
123
What is the recommended treatment for acute VTE during pregnancy?
LMWH is generally used
124
What are the contraindications for ACE-inhibitors and ARBs during pregnancy?
They are contraindicated due to risks to the fetus
125
What is the recommended management for chronic kidney disease during pregnancy?
* Low-dose aspirin
* Close blood pressure monitoring
* Labetalol and methylodopa as first-line agents
126
What is the pathophysiology of autoimmune changes during pregnancy?
Switch from Th1 to Th2 immune predominance
127
What autoimmune condition is a classical example during pregnancy?
Rheumatoid arthritis
128
What are the implications of lupus during pregnancy?
Antiphospholipid syndrome poses a great risk; mothers should be anticoagulated
129
What is the classification of drugs based on pregnancy safety?
* Class A: No harm
* Class B: Limited evidence of harm
* Class C: Evidence of harm but benefits may outweigh risks
* Class D: Evidence of harm, treatment should be avoided unless necessary
* Class X: Contraindicated
130
What is the frequency of seizures during pregnancy?
The frequency of seizures does not increase during pregnancy
131
What is the recommended management for epilepsy during pregnancy?
* High-dose folic acid
* Lamotrigine and levetiracetam as safest options
132
What is gestational diabetes mellitus?
Common condition affecting 5-8% of pregnancies, often asymptomatic
133
What are the risk factors for gestational diabetes mellitus?
* Diabetes
* Increasing maternal age
* Previous gestational diabetes
* Preexisting glucose intolerance
* Family history of diabetes mellitus (type 2)
134
What are common complications of gestational diabetes mellitus?
* Foetal macrosomia
* Intrauterine growth retardation
* Maternal pre-eclampsia
135
What defines gestational thrombocytopenia?
Mild to moderate thrombocytopenia affecting up to 10% of pregnancies
136
What is the predominant symptom of intrahepatic cholestasis?
Itch, especially affecting palms and soles
137
What is acute fatty liver of pregnancy?
Rare condition with significant morbidity and mortality, disorder of the third trimester
138
What are the three diagnostic features of HELLP syndrome?
* Haemolysis
* Elevated liver enzymes
* Low platelets
139
What is the definitive treatment for pre-eclampsia?
Early delivery
140
What are the general symptoms associated with conditions causing necrosis and haemorrhage?
Nausea, vomiting, and epigastric pain
141
What are the three diagnostic features of pre-eclampsia?
Haemolysis, elevated liver enzymes, and low platelets
142
What is the only effective treatment for pre-eclampsia?
Delivery
143
What must be corrected prior to delivery in cases of pre-eclampsia?
DIC (Disseminated Intravascular Coagulation)
144
List some complications of pre-eclampsia.
* Haemorrhage
* Acute liver failure
* Acute renal failure
* Placental abruption
* Stillbirth
145
What are the maternal mortality rates associated with pre-eclampsia?
-1%
146
What role does advanced care planning play in terminal conditions?
It allows predefined people to manage circumstances if the person is incapacitated
147
What is an Advanced Health Directive (AHD)?
A document stating a person's wishes regarding medical treatment in case of incapacitation
148
What is the purpose of an Enduring Power of Attorney (EPOA)?
To manage health decisions on behalf of a person who is incapacitated
149
Who may act as a Statutory Health Attorney (SHA) if no AHD or EPOA exists?
Next-of-kin or family members
150
What is the hierarchy of documentation in patient care?
* Competent Patient
* Advanced Health Directive (AHD)
* Statutory Health Attorney (SHA)
* Public Guardian
151
True or False: The voice of the EPOA overrides the decision of a competent patient.
False
152
What is the foundation of Palliative Medicine?
Managing symptoms to improve quality of life
153
What two outcomes improve with early palliative care involvement in terminal conditions?
* Quality of life
* Duration of survival
154
Which symptom has the biggest impact on quality of life according to patient surveys?
Nausea
155
What medication class is often insufficient for managing cancer pain?
Simple analgesics
156
What are the most commonly used opiate medications in palliative care?
* Morphine
* Oxycodone
157
What should be considered when selecting an opiate for a patient?
* Previous exposure
* Renal function
158
What is the best option for severe renal failure when prescribing opiates?
Fentanyl
159
What should be done if patients use more than 50% of their slow-release dose in PRN format?
Consider increasing their background slow-release dose
160
What is the most effective drug for managing dyspnoea?
Morphine
161
What medications are effective for managing nausea?
* Aprepitant
* Metoclopramide
* Ondansetron
162
What common problem in palliative medicine is often caused by opiate medications?
Constipation
163
What is a common contributing factor to decreased appetite in terminal patients?
* Chemotherapy
* Mucositis
* Nausea
* Constipation
164
What is essential to support patients and families during functional decline?
Home assessment and provision of equipment
165
What should be the approach to oral intake as a patient becomes unresponsive?
Cease all oral intake, no role for parenteral fluids or feeding
166
What is a significant contributor to morbidity in palliative patients?
Pill burden
167
What is the risk associated with cessation of anticoagulation in cancer patients?
High recurrence risk
168
What is the most common reason for palliative care referral?
Metastatic malignancy
169
What is required in cases of malignant spinal cord compression?
Urgent radiotherapy
170
What type of agents are included in vasoactive agents?
* Inotropes
* Vasopressors
* Inodilators
* Other agents
171
What is the primary effect of inotropes?
Increase myocardial contractility
172
What is the effect of vasopressors in the intensive care setting?
Increase systemic vascular resistance by vasoconstriction
173
What do ionodilators primarily focus on?
Ionotropic support at the cost of peripheral vasodilation
174
What is the role of dopamine in clinical practice?
Previously used to improve renal perfusion during shock
175
What is the effect of dopamine at low doses?
Acts only on dopamine receptors to improve renal perfusion
## Footnote
Low doses of dopamine primarily target dopamine receptors without affecting adrenergic receptors
176
What happens as the dose of dopamine escalates?
Begins to have effects on beta and alpha adrenergic receptors
## Footnote
This change in receptor activity occurs as the dose of dopamine increases
177
What has been the trend regarding the use of dopamine in clinical practice over the past decade?
Declined due to a lack of efficacy
## Footnote
There is no evidence supporting routine use of dopamine in acute renal failure
178
What is the '12-12 rule' in ventilator settings?
12 breaths per minute and 12ml/kg tidal volume
## Footnote
This setting can be adjusted to prevent hyperinflation in emphysema or barotrauma in ARDS
179
What is the purpose of Positive End Expiratory Pressure (PEEP)?
Splints open airways and prevents dynamic airway collapse
## Footnote
PEEP helps maintain functional residual capacity and alveoli openness during the respiratory cycle
180
What are the indications for invasive ventilation?
* Respiratory arrest
* Severe hypercapnic respiratory failure (pH <7.25)
* Acute respiratory distress syndrome (ARDS)
* Pulmonary haemorrhage
* Respiratory muscle fatigue
* Loss of consciousness
* General anaesthesia
## Footnote
The decision to ventilate is complex and should consider the likelihood of survival from the acute illness
181
What are the potential complications of endotracheal tube placement?
* Damage to oral cavity, pharynx, or larynx
* Vocal cord damage
* Aspiration events during unplanned intubation
## Footnote
Aspiration events occur at a high frequency, approximately 10%
182
What is a common risk associated with high pressures during ventilation?
Barotrauma
## Footnote
This can lead to alveoli rupture and potential pneumothorax or pneumomediastinum
183
What is the risk of ventilator-associated pneumonia (VAP)?
Approximately 15%
## Footnote
VAP has a high mortality risk, partly due to comorbidities of the patient
184
What is intrinsic PEEP?
Difficulty with complete exhalation leading to gas trapping
## Footnote
Conditions like emphysema or asthma can cause breath stacking and increased functional residual capacity
185
What is the impact of ventilation on cardiovascular function?
Decreased venous return and stroke volume
## Footnote
Increasing PEEP exacerbates this phenomenon
186
What is the common gastrointestinal complication in ventilated patients?
Stress-related gastritis and ulcer formation
## Footnote
Prophylactic proton pump inhibitors or histamine blockers are often used
187
True or False: Dopamine is effective in renal failure.
False
## Footnote
There is no evidence supporting the use of dopamine in acute renal failure
188
Fill in the blank: The tidal volume is adjusted to prevent _______.
[barotrauma]
## Footnote
This adjustment is especially important in patients with ARDS
189
What is the role of FiO2 in ventilation?
Refers to the percentage of oxygen within the delivered air
## Footnote
FiO2 is often started at 100% and titrated down to maintain oxygen saturation
190
What can happen to patients with baseline hypercapnia when over-oxygenated?
They can lose their respiratory drive
## Footnote
Over-oxygenation can lead to complications such as free radical formation and reperfusion injury
