Answer to N-01


Answer: (b) Vitamin C deficiency

 

                                                                          

Vitamin C structure

 Vitamin C (aka Ascorbic acid)

Vitamin C biological functions include:

a)      Cofactor of specific hydroxylation reactions in important processes as the synthesis of collagen, catecholamines, and serotonin.

b)      Facilitation of iron absorption

c)      Anti-oxidant

Sources of Vitamin C:

The richest sources are fruits and vegetables. Common rich sources are citrus fruits and their juices.                                                                      

 

 

oranges

Meats, notably liver, contains vitamin C; however they are not a reliable source for daily requirements. Pressure cooking, roasting, frying, grilling, and other overheating procedures decompose vitamin C. Another way of wasting Vitamin C contents in some foods is the lost of this vitamin when it dissolves in boiling water that is not consumed later.

Scurvy

The deficit of vitamin C produces Scurvy, characterized by superficial hemorrhages, and wounding healing delays. Inflammation and bleeding of the gums with loss of teeth are characteristics of this disease.

                                                                    

 

 

Hemorrhagic “dots” (petechias) appears in the skin around hair follicles. The hemorrhagic lesions increase in size and become more extended with time if the condition is not cured.

The patient shows low resistance to infections and delayed tissue regeneration, so any wound can be infected.

The pathobiochemistry of this disease is related to the participation of Vitamin C in the biosynthesis of collagen. Collagen is the most abundant protein in the human body. Collagen forms molecular cables that strengthen the tendons, and a mesh-like net that support the skin and internal organs. Bones and teeth are made by the addition of minerals to collagen. Typical manifestations of impaired synthesis of collagen as a consequence of a deficit of vitamin C appear in those tissues rich in collagen such as skin, bones, cartilage, dentine,  and capillary walls of blood system.  Hydroxyproline and hydroxylysine are particularly important in the structure of collagen.These modified amino acids give stability to the collagen molecule, and act as attachment site for structural carbohydrates. These amino acids are hydroxylated in the endoplasmic reticulum as a result of posttranslational modifications (the proline and the lysine that are already part of the precursor chain are converted to the corresponding hydroxylated amino acids).

Vitamin C deficiency slows the production of hydroxyproline and hydroxylysine and consequently the construction of new collagen, ultimately causing scurvy. Most of the cases of infant scurvy occur before 24 months of age. Usually, they are consequence of a deficient diet caused by lack of resources and/or lack of appropriate information. The prolonged consumption of pasteurized or overheated milk and the deficient ingestion of citrics and other fruits and vegetables, are risk factors.  

Recommended reading for additional information about Scurvy:

Kumaravel Rajakumar: Scurvy

Editors: Kathryn Schwarzenberger, MD; Michael J Wells, MD; Van Perry, MD,; Catherine Quirk, MD; Dirk M Elston, MD: Scurvy

Food Sources of Vitamin C ranked by milligrams of vitamin C per standard amount; also calories in the standard amount. (All provide ≥ 20% of RDA for adult men, which are 90 mg/day.)

Food, Standard Amount Vitamin C (mg) Calories
Guava, raw, ½ cup 188 56
Red sweet pepper, raw, ½cup 142 20
Red sweet pepper, cooked, ½ cup   116 19
Kiwi fruit, 1 medium 70 46
Orange, raw, 1 medium 70 62
Orange juice, ¾ cup 61-93 79-84
Green pepper, sweet, raw, ½ cup 60   15
Green pepper, sweet, cooked, ½ cup 51   19
Grapefruit juice, ¾ cup 50-70 71-86
Vegetable juice cocktail, ¾ cup 50 34
Strawberries, raw, ½ cup 49 27
Brussels sprouts, cooked, ½ cup 48 28
Cantaloupe, ¼ medium 47 51
Papaya, raw, ¼ medium 47 30
Kohlrabi, cooked, ½ cup 45 24
Broccoli, raw, ½ cup 39 15
Edible pod peas, cooked, ½ cup 38 34
Broccoli, cooked, ½ cup 37 26
Sweetpotato, canned, ½ cup 34   116
Tomato juice, ¾ cup 33 31
Cauliflower, cooked, ½ cup 28 17
Pineapple, raw, ½ cup 28 37
Kale, cooked, ½ cup 27 18
Mango, ½ cup 23 54

Source: Nutrient values from Agricultural Research Service (ARS) Nutrient Database for Standard Reference, Release 17. Foods are from ARS single nutrient reports, sorted in descending order by nutrient content in terms of common household measures. Food items and weights in the single nutrient reports are adapted from those in 2002 revision of USDA Home and Garden Bulletin No. 72, Nutritive Value of Foods. Mixed dishes and multiple preparations of the same food item have been omitted from this table.

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