Polyene antibiotics exhibit their action on:

 # Polyene antibiotics exhibit their action on:

A. Cell membrane

B. Cell wall

C. Cell nucleus

D. Ribosomes

The correct answer is A. Cell Membrane.

Amphotericin, the polyenes antibiotics, have high affinity for ergosterol of fungal cell membranes to orient themselves to produce micropore through which ions, amino acids and water-soluble substances move out. It is not effective against bacteria as it does not contain sterol in their cell membrane. 

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Early bell stage is associated with:

 # Early bell stage is associated with:

A. Initiation

B. Proliferation

C. Histodifferentiation

D. Apposition

The correct answer is C. Histodifferentiation.

Morphologic stages and physiologic process related to each stage: 

• Dental lamina & Bud stage -Initiation 

• Cap stage -Proliferation 

• Early bell stage - Histodifferentiation 

• Advanced bell stage - Morpho-differentiation 

• Formation of enamel & dentin matrix - Apposition 

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Treatment of dehydrated child patient is:

 # Treatment of dehydrated child patient is:

A. 0.9% normal saline

B. 5% dextrose

C. 10% dextrose

D. 50% dextrose

The correct answer is B. 5% dextrose.

5% dextrose supplies calories, but not electrolytes. The solution can only be used when the patient does not require any electrolytes but a solution to replenish his blood volume along with some nutrition.

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Conjugated and unconjugated bilirubins are increased in:

 # Conjugated and unconjugated bilirubins are increased in: 

A. Prehepatic jaundice 

B. Hepatocellular jaundice 

C. Posthepatic jaundice

D. Hemolytic jaundice 

The correct answer is B. Hepatocellular jaundice.

In hepatocellular jaundice, bilirubin transport across the hepatocytes may be impaired at any point between uptake of unconjugated bilirubin into the cells and transport of conjugated bilirubin into the canaliculi. So the concentrations of both conjugated and unconjugated bilirubin in the blood increase. 

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Strict vegetarian diet results in the deficiency of:

 # Strict vegetarian diet results in the deficiency of:

A. Vitamin B1

B. Biotin

C. Vitamin B12

D. Vitamin D

The correct answer is C. Vitamin B12.

Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, in both fatty acid and amino acid metabolism. It is important in the normal functioning of the nervous system via its role in the synthesis of myelin, and in the circulatory system in the maturation of red blood cells in the bone marrow. Plants do not need cobalamin and carry out the reactions with enzymes that are not dependent on it.

Vitamin B12 is the most chemically complex of all vitamins, and for humans, the only vitamin that must be sourced from animal-derived foods or supplements. Only some archaea and bacteria can synthesize vitamin B12. Most people in developed countries get enough B12 from the consumption of meat or foods with animal sources. Foods containing vitamin B12 include meat, clams, liver, fish, poultry, eggs, and dairy products. Grain-based foods can be enriched with the vitamin. Supplements and medications are available to treat and prevent vitamin B12 deficiency. They are taken by mouth, but for the treatment of deficiency may also be given as an intramuscular injection.

The diets of vegetarians and vegans may not provide sufficient B12 unless a dietary supplement is consumed. A deficiency in vitamin B12 may be characterized by limb neuropathy or a blood disorder called pernicious anemia, a type of megaloblastic anemia, causing a feeling of tiredness and weakness, lightheadedness, headache, breathlessness, loss of appetite, pins and needles sensations, changes in mobility, severe joint pain, muscle weakness, memory problems, decreased level of consciousness, brain fog, and many others. If left untreated in infants, deficiency may lead to neurological damage and anemia. Folate levels in the individual may affect the course of pathological changes and symptomatology of vitamin B12 deficiency.

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Wernicke’s encephalopathy is due to the deficiency of:

 # Wernicke’s encephalopathy is due to the deficiency of:

A. Thiamine

B. Vitamin B12

C. Niacin

D. Vitamin B2

The correct answer is A. Thiamine. 

■ Thiamine deficiency in its early stage induces anorexia and nonspecific symptoms (e.g., irritability, decrease in short-term memory). 

■ Prolonged thiamine deficiency causes beriberi, which is classically categorized as wet or dry, although there is considerable overlap. In either form of beriberi, patients may complain of pain and paresthesia. 

■ Wet beriberi presents primarily with cardiovascular symptoms due to impaired myocardial energy metabolism and dysautonomia and can occur after 3 months of a thiamine deficient diet. Patients present with an enlarged heart, tachycardia, high-output congestive heart failure, peripheral oedema and peripheral neuritis. 

■ Patients with dry beriberi present with asymmetric peripheral neuropathy of the motor and sensory systems with diminished reflexes. The neuropathy affects the legs most markedly, and these patients have difficulty rising from a squatting position. 

■ Alcoholic patients with chronic thiamine deficiency also may have central nervous system (CNS) manifestations known as Wemicke's encephalopathy, consisting of horizontal nystagmus, ophthalmoplegia (due to weakness of one or more extraocular muscles), cerebellar ataxia, and mental impairment. 

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Rule of Ten is for:

 # Rule of Ten is for:

A. Pheochromocytoma

B. MEN-I syndrome

C. Adrenal hyperplasia

D. Parathyroid

The correct answer is A. Pheochromocytoma.

Pheochromocytoma:- 

For diagnosis and management of this disease classic "rule of tens is applicable." 

• 10% of these neoplasms occur in children 

• 10% of these neoplasms associated with familial syndromes 

• 10% of sporadic cases of these neoplasms are bilateral 

• 10% of these neoplasms are extra-adrenal 

• 10% of these neoplasms are malignant 

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