Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GIT > Biochem 2 > Flashcards

Biochem 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
Git Commands flashcards
1
Q

How does ethanol act on the brain?

A

It is a small molecule which can cross the BBB
Ethanol makes nerve membranes leaky
Impaired nervous function and even in severe cases death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What part of the brain is affected first by alcohol?

A

Cerebral cortex - leading to impaired judgement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What part of the brain is affected second and third by alcohol?

A

Forebrain - memory and emotions

Cerebellum - balance and movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What part of the brain is affected fourth by alcohol? What are the consequences?

A

Brain stem breathing circulation (can be suppressed and cause death)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is considered low medium ad high risk drinking per day for a male?

A

2
4-6
6+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is considered low medium ad high risk drinking per day for a female?

A

Up to 2
2-4
4+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where is alcohol dependence most common?

A

Dependence is generally higher in rural and colder states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the symptoms of severe dependence?

A

Severe Dependence exists when withdrawal causes tremors, anxiety, sweating or vomiting

Dependence is a continuum from mild to severe. It is more likely when family or social groups exhibit high drinking patterns. People who cannot stop drinking, when they realise that they should, are dependent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many Australians likely have brain damage from alcohol consumption at current levels?

A

2 Million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is Wernicke Korsakoff Syndrome?

A

Neurotoxicity due to thiamine deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What percentage of Australians are affected by Wernicke Korsakoff Syndrome?

A

2%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What cause Wernicke Korsakoff Syndrome?

A 
Dietary deficiency (little fruit and veg) - no thiamine.
Also alcohol metabolises thiamine further reducing its level
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How can Wernicke Korsakoff Syndrome be reversed?

A

Thiamine injection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the symptoms of Wernicke Korsakoff Syndrome?

A 
Eyes uncoordinated (nystagmus), 
Wide step, 
Confusion, 
Hypothermia, 
Amnesia and confabulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are some signs of alcoholism?

A 
Neurological disturbances
Brain damage 
Heart disease - Irregular heart beat
Jaundice
Altered breath
Oesophageal varices 
Feminization (altered sex hormones - development of breasts)
Extensively scarred liver
Portal Hypertension 
Enlarged collateral vessels
Ascites
Hand tremor
Hypogonadism
Infertility in women 
Impotence in men
Osteoporosis
East bruising 
Muscle wasting
Oedema
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is fatty liver?

A

Fatty liver occurs rapidly and is reversible (detected by ultrasound).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is alcoholic hepatitis?

A

Alcoholic hepatitis with widespread inflammation. This occurs in up to 50% of heavy drinkers and may be recognised by the presence of fever, jaundice and abdominal pain. This condition carries a mortality of between 15 - 20%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is alcoholic cirrhosis?

A

Alcoholic cirrhosis is diagnosed in some 15-30% of heavy drinkers. The cirrhotic liver is characterised by extensive fibrosis that distorts the internal structure of the liver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What percentage of the liver is required for normal function?

A

Only 40% of a liver’s functioning hepatocytes are required for its adequate performance. This is due to their efficiency and their ability to regenerate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is serum albumin concentration affected by liver disease?

A

Usually normal in chronic liver diseases until cirrhosis is present.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where is alcohol metabolised and where does it pass?

A

> 90% is metabolised in liver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where does alcohol enter the blood?

A

~30% enters blood from stomach.

~70% enters blood from gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What happens to alcohol in the stomach?

A

Some undergoes first pass metabolism (alcohol dehydrogenase is gastric mucosa)
The rest either passes into the SI or enters the blood

24
Q

How is alcohol absorption slowed?

A

Fatty in foods

25
Q

What pathways are used to metabolise alcohol?

A 
Alcohol dehydrogenase (ADH) 
MEOS 
Catalase (don't worry about it)
26
Q

What is the pathway of ethanol breakdown using ADH?

A

(NAD+ → NADH + H+)
Ethanol → Acetaldehyde
(ADH)

             (NAD+ → NADH + H+)  Acetaldehyde      →        Acetate 
                      (ALDH)

Acetate → Acetyl CoA (can enter the TCA cycle or be stored as fat

27
Q

What is a consequence of the ADH pathway?

A

The breakdown of ethanol leads to the production of NADH which represses gluconeogenesis and can lead to hypoglycaemia

28
Q

What cytochrome is is recruited in the MEOS pathway?

A

CYP2E1

It can be induced

29
Q

What can be said about MEOS and catalase?

A

They are minor pathways in moderate drinkers

30
Q

How much alcohol in 1 standard drink?

A

10g

31
Q

How much does 1 standard drink raise blood alcohol?

A

0.015 g/l

32
Q

How much alcohol can a human clear per hour?

A

Most humans clear alcohol at approximately one standard drink (10g alcohol) per hour. This is equivalent to a decrease of 0.015% blood alcohol per hour.

33
Q

Is alcohol cleared at a consistent rate?

A

Yes - ADH is absolutely saturated at a concentration of 3-4mM which is about 1 standard drink or 0.015g/l

34
Q

Are breath tests accurate?

A

Blood alcohol is measured with high accuracy by gas chromatography. Breath tests usually give slight underestimates.

35
Q

What effects does alcohol have on drug clearance?

A

Alcohol has two alternate effects on drugs:
1. Prevents drug clearance when alcohol is present.

  1. Promotes drug clearance by elevated CYP 2E1 when alcohol is not present
36
Q

Name a few common drugs which use the CYP 2E1 pathway?

A

Warfarin, paracetamol

37
Q

What change needs to be made to those taking warfarin if also using alcohol?

A

Need to increase protective dose when patient is also taking alcohol (increases warfarin destruction by CYP 2E1)

38
Q

What are the causes of Alcohol Induced Liver damage?

A

Damaged cells release inflammatory agents such as eicosanoids, cytokines and endotoxins. Damaged tissue is destroyed by the immune system.

39
Q

What happens to sex hormones in chronic alcohol consumption?

A

Affected by chronic alcohol consumption, probably by stimulating microsomal modification or destruction of steroids

40
Q

What are the outcomes of low testosterone?

A

Testicular atrophy
Gynaecomastia
Loss of libido
Feminisation of hair patterns

In women libido is lowered and breast cancer risk increases

41
Q

What happens if someone inherits an inactive variant of ALDH2 enzyme?

A

The ALDH2 enzyme is the more important aldehyde dehydrogenase (located in the mitochondria)
Increased circulating acetaldehyde produces general vasodilatation with a striking facial flushing response.

42
Q

What does Disulfiram do?

A

Irreversible inhibitor of aldehyde dehydrogenase

Ingestion of alcohol → acetaldehyde accumulation causing tachycardia, flushing, dyspnoea, nausea & vomiting.

43
Q

Are genes thought to play a role in alcohol addiction?

A

Yes

We talked about Dopamine D2 receptor

44
Q

What is naltrexone?

A

Opioid receptor antagonist Blocks alcohol induced release of dopamine in Nucleus Accumbens. Diminishes pleasurable effects and craving for alcohol. The most clinically successful drug when used with the Sinclair method

45
Q

What is nalmefene?

A

µ and α opioid receptor antagonist – less hepatotoxic than naltrexone.

46
Q

What do dopaminergic drugs do?

A

Tiapride: a D2 receptor antagonist. Eases symptoms of withdrawal for treatment of acute & chronic alcoholism

47
Q

What is Acamprosate (trade name CAMPRAL)?

A

GABA receptor agonist that normalises glutamanergic mediated reaction to alcohol withdrawal. Trials show 60% abstinence compared with 22% for placebo

48
Q

What is Fetal Alcohol syndrome?:

A

Birth disorders brought on by alcohol consumption during pregnancy.
Children with FAS typically have small heads, small eyes and certain facial malformations.

49
Q

How does alcohol cause dehydration?

A

Production of antidiuretic hormone by the brain (pituitary) signals the kidney to take water back from the urine. Alcohol interferes with pituitary function. Low antidiuretic hormone levels result in more body water passing into the urine. Despite high fluid intake with the alcoholic drinks even more is lost. The body becomes dehydrated.

50
Q

What impact does dehydration have on the brain?

A

Dehydration of the brain (the brain shrinks!) leads to headache and the death of brain cells

51
Q

What is GGT?

A

Gamma-glutamyltranspeptidase (GGT)

52
Q

When is GGT elevated?

A

May be elevated in virtually any liver disease and even sometimes in normal individuals. GGT is induced by many drugs, including alcohol, and its serum activity may be increased in heavy drinkers even in the absence of liver damage or inflammation.

53
Q

What is ALT?

A

Alanine transaminase

54
Q

When is ALT elevated?

A

is elevated in all types of hepatitis (viral, alcoholic, drug-induced, etc.) due to hepatocyte damage.

55
Q

What is a clear marker of elevated alcohol consumption?

A

carbohydrate deficient transferrin (CDT)

GIT (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions