vitamins1

Question 1

what are the vitamins? and what we call them?

Answer 1

organic compounds occurring in small quantities in natural foods (micronutrients))

Question 2

why the vitamins are important?

Answer 2

they are necessary for the growth and maintenance of good health. they are essential for metabolism. they participate in the metabolism of lipids, proteins, carbohydrates

Question 3

*which vitamins act as hormons?

Answer 3

both vitamin A and vitamin D act as hormones

Question 4

which vitamins act as coenzymes?

Answer 4

many water-soluble vitamins act as coenzymes in metabolic reactions.

Question 5

*what is the only one fat-soluble vitamin that has a coenzyme function?

Answer 5

vitamin K

Question 6

how do we get the vitamins?

Answer 6

vitamins cannot be synthesized in adequate quantities by us, intestinal bacteria can synthesize, some vitamins must be supplied by the diet.

Question 7

*can the body store water soluble vitamins?

Answer 7

with the exception of vitamin B12, the body has no storage capacity for water-soluble vitamins.

Question 8

what are the vitamins deficiency reasons?

Answer 8

inadequate intake, poor absorption from gastrointestinal tract= (GIS), inefficient utilization, increased loss, increased demand.

Question 9

what may deficiencies lead to and how do they develop?

Answer 9

deficiencies lead to specific clinical syndromes, may develop as a component of general malnutrition, may themselves be a cause of illness, may develop during Increased demand periods such as pregnancy or adolescent growth spurt, in old age deficiencies may be associated with less efficient intestinal absorption, may occur as a complication of GIS surgery, multiple micronutrient deficiencies are much more common than single ones.

Question 10

*when do some vitamins become toxic?

Answer 10

some vitamins (fat-soluble) are toxic in excess

Question 11

*what happens quickly in water-soluble vitamins?

Answer 11

water-soluble vitamins are excreted readily in urine (toxicity is rare), deficiency may occur quickly.

Question 12

how do vitamins differ from other organic food

Answer 12

vitamins do not enter into tissue structures unlike proteins, vitamins do not undergo degradation for providing energy, unlike carbohydrates and lipids.

Question 13

list the categories of vitamins and their members

Answer 13

vitamins:
water-soluble:

1-non-B complex- (ascorbic acid (vitamin C)).

2-B complex
1-energy releasing(Thiamine (Vitamin B1), Riboflavin (Vitamin B2), Niacin (vitamin B3), Biotin (vitamin B7), Pantothenic acid).

3-hematopoietic- folic acid (vitamin B9), Cobalamin (Vitamin B12).

4-Pyridoxine (Vitamin B6) is important for protein metabolisim, pyridoxal, pyridoxamine.

fat-soluble:
vitamin: A, D, K, E.

Question 14

*list the water-soluble vitamins

Answer 14

Thiamine(Vitamin B1), Riboflavin(Vitamin B2), Niacin(Vitamin B3), Pyridoxine(Vitamin B6), Biotin(Vitamin B7), Pantothenic Acid(vitamin B5), Folic Acid, Cobalamine(Vitamin B12), Ascorbic Acid (Vitamin C).

Question 15

why B-complex vitamins are important?

Answer 15

because they are essential for normal metabolism, serve as coenzymes in many reactions in lipid, carbohydrate, and protein metabolism.

Question 16

*when does the requirement of B-complex vitamins increase?

Answer 16

the greater the caloric intake the larger the requirement of B vitamins. increased energy supply in particular form simple carbohydrates requires increased amounts of B vitamins. high carbohydrates intake requires a greater intake of Thiamine and other B vitamins. therefore Beriberi might develop on a high carbohydrate diet.

Question 17

which disease may develop on a high-carbohydrate diet?

Answer 17

Beriberi might develop on a high-carbohydrate diet.

Question 18

why is Thiamine (vitamin B1) important?

Answer 18

because it plays a key role in the energy metabolism of most cells.
particularly important in tissues of CNS (Central Nervous System).

Question 19

*what is the biologically active coenzyme form of Thiamine (vitamin B1)?

Answer 19

Thiamine Pyro Phosphate (TPP)

Question 20

what are the coenzyme functions of Thiamine Pyro Phosphate (TPP)?

Answer 20

Transketolase (Pentose Phosphate Pathway ).
Pyruvate Dehydrogenase ( Oxidative
Decarboxylation ).
Alpha Keto Glutarate Dehydrogenase ( Oxidative
Decarboxylation ).
Branched Chain Alpha Keto Acid Dehydrogenase of
Muscle Cells.

Question 21

list the Thiamin deficiency causes

Answer 21

decreases in pyruvate dehydrogenase and alpha keto glutarate dehydrogenase enzyme's activates:
a decline in ATP production
                     |
                     |
impaired cellular functions

Question 22

what causes Beriberi? and what does it do?

Answer 22

due to thiamine deficiency in diet (so beriberi is a thiamine deficiency):
Inflammation of multiple nerves
(Polyneuritis ).
Heart disease ( Cardiopathy ).
Edema ( Swelling ).

Question 23

what is Beriberi?

Answer 23

Severe Thiamine deficiency syndrome is found in areas where Polished rice is the major component of the diet.
Peripheral Neurological deficit or.
Edema due to Cardiac dysfunction.

Question 24

*what is dry Beriberi? and what doe it cause?

Answer 24

dry Beriberi: without fluid retention.

Peripheral Neuropathy especially in the legs. (foot drop) and (wrist drop).

Question 25

*what is wet Beriberi?

Answer 25

wet (cardiovascular) Berberi: associated with cardiac failure with edema.

Question 26

*what is Wernicke Korsakoff Syndrome? and what is the reason behind it?

Answer 26

2 conditions that often happen together; Wernicke encephalopathy and Korsakoff syndrome. reason: Dietary insufficiency or Impaired intestinal absorption of Thiamine. Seen primarily in association with chronic alcoholism.

Question 27

*what are the Wernicke Korsakoff Syndrome | symptoms?

Answer 27

Mental confusion. Gait ataxia. Nystagmus ( Involuntary rhythmic shaking ‘’Dancing ‘’ of Eyes ). Ophthalmoplegia (Weakness of eye muscles ).

Question 28

what are the symptoms of Wernicke Encephalopathy? how is it treatable? *and what are the tests used to assess Thiamine's status?

Answer 28

Wernicke encephalopathy has hallucinations and memory problems and Korsakoff dementia. treatable with thiamine supplementation but memory recovery is typically incomplete. tests used to assess thiamine's status: red blood cell transketolase activity.

Question 29

what are the tests used to assess Thiamine's status?

Answer 29

red blood cells transketolase activities.

Question 30

case study

Answer 30

A 20-year-old female was brought to the emergency department with respiratory distress • A known Alcoholic • On examination she was pale, malnourished, agitated, and acutely ill • She was in acute respiratory distress • Her pulse was 110/minute, there was marked tachycardia and a systolic murmur was heard along the left sternal edge • Bilateral crepitations were felt in the lungs, neck veins were engorged and liver was also enlarged, although non-tender • Bilateral foot drop what is the probable diagnosis? • Patient is most probably suffering from Cardiac beriberi (wet form) *• The criteria for diagnosing cardiac beriberi is: • (1) Signs of heart failure, • (2) Signs of neuropathies, • (3) History of alcoholism or poor nutritional history, • (4) Exclusion of other signs of heart failure, *• (5) Low Red Blood Cell Transketolase activity, • (6) Response by Thiamine administration %what is the probable diagnosis? * Patient is a known alcoholic. * Malnourished. * Heart failure. * Bilateral foot drop. * The probable diagnosis is Thiamine deficiency, which can be confirmed by RBC Transketolase activity. * Thiamine deficiency (causing Beriberi) is most common among people subsisting on white rice or highly refined carbohydrates in developing countries and among alcoholics. * Thiamine is given to help diagnose and treat the deficiency. * Thiamine deficiency often occurs with other B vitamin deficiencies, multiple water-soluble vitamins are usually given for several weeks.

Question 31

what are the criteria for diagnosing cardiac beriberi?

Answer 31

1-signs of heart failure. 2-signs of neuropathy. 3-history of alcoholism or poor nutritional history. 4-exclusion of other signs of heart failure. 5-low red blood cell transketolase activity. 6-response by thiamine administration.

Question 32

thiamine deficiency can be confirmed by.....

Answer 32

RBC transketolase.

Question 33

among which people Thiamine deficiency (causing Beriberi) is most common?

Answer 33

``` Thiamine deficiency (causing Beriberi) is most common among people subsisting on white rice or highly refined carbohydrates in developing countries and among alcoholics. Thiamine is given to help diagnose and treat the deficiency. Thiamine deficiency often occurs with other B vitamin deficiencies, multiple water-soluble vitamins are usually given for several weeks. ```

Question 34

Riboflavin (vitamin B2) is required for.... and .... synthesis

Answer 34

FMN and FAD

Question 35

what are the characteristics of FMN and FAD?

Answer 35

* Reversibly accepts 2 Hydrogen atoms * Bound tightly, sometimes covalently to Flavoenzymes * Function in Mitochondrial electron transfer

Question 36

what is Riboflavin deficiency?

Answer 36

• Not associated with a major human disease • Frequently accompanies other vitamin deficiencies.

Question 37

*what are the symptoms of riboflavin deficiency?

Answer 37

* SYMPTOMS; * Dermatitis (inflammation of the skin) * Angular stomatitis (Inflammation of the corners of the mouth) * Cheilosis ( Fissuring at the corners of the mouth ) * Glossitis ( Tongue appearing smooth and dark ) * Corneal vascularization

Question 38

what is Niacin (vitamin B3)=Nicotinic acid?

Answer 38

Nicotin amide occurs in the diet | Nicotin amide is readily deaminated in the body so; forms Niacin.

Question 39

Niacin is required for the synthesis of what?

Answer 39

NAD,NADH,NADPH.

Question 40

*.... and .... function as coenzymeS in redox reactions

Answer 40

NAD and NADP

Question 41

requirement of niacin is related to what?

Answer 41

requirement for Niacin is related to energy expenditure.

Question 42

Niacin is synthesized from what?

Answer 42

Tryptophan

Question 43

what is Pellagra?

Answer 43

Tryptophan and/ or Niacin Deficiency. | pelle= skin agra= rough

Question 44

what are the symptoms of pellagra?

Answer 44

3D symptoms: • Photosensitive Dermatitis (Sunburn-like skin lesions in areas of the body exposed to sunlight and to pressure. • Dementia and Diarrhea.

Question 45

what happens if the Pellagra is untreated?

Answer 45

multi-organ failure and death. | 4D= Dermatitis, Diarrhea, Dementia, Death

Question 46

*what is Casal necklace?

Answer 46

a Pellagra symptom, Dermatitis is precipitated by exposure to sunlight, *Increased pigmentation around the neck is known as Casal necklace.

Question 47

what is Zein and what are its characteristics?

Answer 47

Zein is a corn protein, it is low in both Tryotphan and Niacin.

Question 48

corn based diets can cause what?

Answer 48

Pellagra.

Question 49

what are the Pelleagra precipitating factors?

Answer 49

corn rich diet and alcoholism.

Question 50

*what is Hartnup disease?

Answer 50

Intestinal and renal tubular reabsorption defect of Neutral amino acids ( Gly, Ala, Val, Tre, Leu, Ile, Phe, Tyr, Trp, His ) • Defective reabsorption of Tryptophan • Can result in Pellagra like symptoms

Question 51

*how to diagnose Hartnup disease? and what is the therapy?

Answer 51

Diagnosis; • In Urine; High levels of Neutral amino acids. • In Plasma; Low levels of Neutral amino acids. • Therapy; Nicotin amide daily, Sun protection.

Question 52

what are the symptoms and signs of hartnup disease?

Answer 52

red scaly photosensitive rashes, diarrhea, renal aminoaciduria, seizures.

Question 53

how does Niacin treat Hyperlipidemia?

Answer 53

decreases both levels in the blood of TG, triglyceride (in VLDL, very low-density lipoprotein), and cholesterol (in LDL, low-density lipoprotein)

Question 54

what do the high doses of Niacin cause? and what is that reaction accompanied with? and what can reduce this side effect?

Answer 54

• Can cause acute, Prostaglandin- mediated flushing • Transient vasodilation of the cutaneous vessels and Histamine release, Reaction is accompanied by itching, burning, and tingling. aspirin can reduce this side effect.

Question 55

what is Pantothenic acid (vitamin B5)?

Answer 55

``` Forms a part of Coenzyme A molecule. • Acetyl CoA • Succinyl CoA • Fatty acyl CoA its function is Acyl group transfer. it is widely distributed. rich sources; eggs, liver, and yeast. no evidence of deficiency in humans. ```

Question 56

where is the Pyridoxine (vitamin B6), Pyridoxal, Pyridoxamine found?

Answer 56

Pyridoxine occurs primarily in plants. | Pyridoxal and Pyridoxamine are found in animal foods.

Question 57

*what do Pyridoxine, Pyridoxal, Pyridoxamine do?

Answer 57

• Participates in Carbohydrate and Lipid metabolism | *• Particularly important for Amino acid metabolism

Question 58

*what is the biologically active coenzyme form of Pyridoxine, Pyridoxal, Pyridoxamine?

Answer 58

Biologically active Coenzyme form: Pyridoxal phosphate is Coenzyme for enzymes, particularly in Amino acid metabolism. * Pyridoxal phosphate; Coenzyme of Transamination, Deamination, Decarboxylation, and Condensation reactions.

Question 59

what are the reactions that Pyridoxine is involved in and how many are they?

Answer 59

• Involved in more than 100 reactions in carbohydrate and lipid metabolism • In the synthesis, catabolism, and interconversion of amino acids • In the metabolism of one-carbon units

Question 60

Pyridoxin is required for the synthesis of what? and what does it influence?

Answer 60

* Neurotransmitters Serotonin and Noradrenaline * Sphingosine, a component of sphingomyelin and sphingolipids and * Heme * Influences immune function

Question 61

*Vitamin B6 requirements increase with what and why?

Answer 61

Because of its role in Amino acid metabolism, Vitamin B6 | requirements increase with high protein intake.

Question 62

Deficiency of vitamin B6 causes what?

Answer 62

Neurologic symptoms and Anemia

Question 63

Mild form deficiency of vitamin B6 causes what?

Answer 63

causes irritability, nervousness, and depression.

Question 64

*severe deficiency of vitamin B6 causes what? and it is associated with what?

Answer 64

*peripheral neuropathy, convulsions, and coma. and it is also associated with *Sideroblastic anemia(Anemia characterized by the presence of nucleated red blood cells with iron granules) • Dermatitis, cheilosis, and glossitis

Question 65

decreased levels of vitamin B6 are in what cases?

Answer 65

``` • Alcoholism • Obesity • Malabsorption states (Crohn’s disease, celiac disease, and ulcerative colitis) • End-stage renal disease • Autoimmune conditions ```

Question 66

what is vitamin B7 called?

Answer 66

Biotin, vitamin H, because in German language Haar= hair, Haut= skin

Question 67

*what does Biotin (vitamin B7) do?

Answer 67

*act as a coenzyme for carboxylation reactions. | serves as a carrier of activated carbon dioxide.

Question 68

Biotin (vitamin B7) serves as a coenzyme in multienzyme complexes that is involved in what?

Answer 68

* Carboxylation reactions, * Lipogenesis * Gluconeogenesis * Catabolism of Branched-chain amino acids

Question 69

how does Biotin (vitamin B7) deficiency occur?

Answer 69

• Biotin is widely distributed in food • Intestinal bacteria provide most part of our Biotin requirements • Deficiency does not occur naturally

Question 70

*what are the Biotin (vitamin B7) deficiency symptoms

Answer 70

Dermatitis, *Hair loss, loss of appetite, Nausea, Hallucinations, Muscle pain.

Question 71

what is Avidin?

Answer 71

Avidin act as a Biotin (vitamin B7) antagonist, • A protein present in Egg White • Raw Egg White has a great affinity to Biotin • Avidin tightly binds Biotin and prevents its absorption from the intestine • One molecule of Avidin can combine four molecules of Biotin • With a normal diet; Eating 20 Raw eggs/ day is required to induce Biotin deficiency. • Addition of raw egg White to diet as a source of protein can induce Biotin deficiency’s symptoms • Avidin is heat labile • Boiling of egg neutralize Avidin’s inhibitory activity