Biochemistry
1 questionsWhich amino acid in Jowar is responsible for its pellagragenic effect?
NEET-PG 2012 - Biochemistry NEET-PG Practice Questions and MCQs
Question 551: Which amino acid in Jowar is responsible for its pellagragenic effect?
- A. Leucine (Correct Answer)
- B. Lysine
- C. Tryptophan
- D. Methionine
Explanation: ***Leucine*** - A high intake of **leucine**, an essential amino acid, interferes with the metabolism of **tryptophan** and niacin, leading to **pellagra**. - Jowar (sorghum) contains high levels of leucine, which, when it forms a major part of the diet, can induce **niacin deficiency**. *Lysine* - Lysine is an essential amino acid and is generally considered to be in **limited supply** in many cereal grains, making it a desirable amino acid to increase in diets. - It does not directly contribute to the pellagragenic effect; rather, a deficiency in lysine can be a nutritional concern. *Tryptophan* - Tryptophan is a **precursor to niacin (Vitamin B3)** in the body; a deficiency in tryptophan can lead to pellagra. - The high leucine content in jowar interferes with the conversion of tryptophan to niacin, thus exacerbating niacin deficiency. *Methionine* - Methionine is an **essential sulfur-containing amino acid** important for various metabolic functions and protein synthesis. - It is not directly implicated in the pellagragenic effect associated with high jowar consumption.
Community Medicine
2 questionsNational Leprosy Eradication Programme was started in -
Multi-purpose worker scheme in India was introduced following the recommendation of ?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 551: National Leprosy Eradication Programme was started in -
- A. 1949
- B. 1955
- C. 1973
- D. 1983 (Correct Answer)
Explanation: **Correct: 1983** - The **National Leprosy Eradication Programme (NLEP)** was launched in India in **1983** - Its goal was to eliminate leprosy as a public health problem by reducing its prevalence rate to less than 1 case per 10,000 population - This marked the shift from control to eradication strategy with the introduction of **Multi-Drug Therapy (MDT)** *Incorrect: 1949* - This year is not associated with the inception of a national leprosy eradication program in India - While efforts against leprosy existed, a comprehensive national program was not established at this time *Incorrect: 1955* - The **National Leprosy Control Programme (NLCP)** was launched in India in **1955** - This was a control program, preceding the eradication program, focusing on diagnosis and treatment with Dapsone monotherapy - NLCP was later upgraded to NLEP in 1983 *Incorrect: 1973* - This year is not cited as the start date for the national leprosy eradication program in India - The focus shifted from control to eradication in 1983 with the adoption of WHO-recommended MDT
Question 552: Multi-purpose worker scheme in India was introduced following the recommendation of ?
- A. Srivastava Committee
- B. Bhore Committee
- C. Kartar Singh Committee (Correct Answer)
- D. Chadha Committee
Explanation: ***Kartar Singh Committee*** - The **Kartar Singh Committee** (1973) recommended the implementation of the **multi-purpose worker scheme** in India. - This scheme aimed to integrate several health services at the grassroots level through a single health worker. *Srivastava Committee* - The **Srivastava Committee** (1975) focused on the creation of a **Medical and Health Education Commission** to reform medical education. - It did not specifically recommend the multi-purpose worker scheme. *Bhore Committee* - The **Bhore Committee** (1946), also known as the Health Survey and Development Committee, recommended a comprehensive health service with an emphasis on preventive and curative care. - It laid conceptual groundwork for primary healthcare but did not specifically propose the multi-purpose worker scheme, which came much later. *Chadha Committee* - The **Chadha Committee** (1963) reviewed India's health infrastructure and medical education. - It focused on health center development and medical college expansion, not the multi-purpose worker scheme.
Internal Medicine
3 questionsWhich visual disturbance is commonly associated with Vitamin B12 deficiency?
Ataxia, nystagmus, and ophthalmoplegia are seen in which of the following conditions?
Madarosis is seen in ?
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 551: Which visual disturbance is commonly associated with Vitamin B12 deficiency?
- A. Centrocaecal scotoma (Correct Answer)
- B. Binasal hemianopia
- C. Constriction of peripheral vision
- D. Bitemporal hemianopia
Explanation: No relevant citations could be added to the original explanation because the provided references did not specifically address the association between Vitamin B12 deficiency and centrocaecal scotoma. ***Centrocaecal scotoma*** - **Vitamin B12 deficiency** can lead to optic neuropathy, which often manifests as a **centrocaecal scotoma**, affecting central and paracentral vision. - This visual impairment is due to **demyelination of the optic nerve fibers** caused by the deficiency. *Binasal hemianopia* - This type of visual field defect is rare and typically caused by lesions that compress the uncrossed retinal nerve fibers, such as **bilateral internal carotid artery aneurysms** or **bilateral optic nerve disease**. - It does not directly correlate with **Vitamin B12 deficiency**. *Constriction of peripheral vision* - **Peripheral vision loss** is associated with conditions like **glaucoma** or advanced **retinitis pigmentosa**. - It is not a characteristic visual disturbance of **Vitamin B12 deficiency**. *Bitemporal hemianopia* - This visual field defect is commonly caused by compression of the **optic chiasm**, most often due to a **pituitary adenoma**. - It results in loss of vision in the outer half of both visual fields and is not linked to **Vitamin B12 deficiency**.
Question 552: Ataxia, nystagmus, and ophthalmoplegia are seen in which of the following conditions?
- A. 3rd nerve palsy
- B. Wernicke encephalopathy (Correct Answer)
- C. Myasthenia gravis
- D. Chronic progressive external ophthalmoplegia
Explanation: ***Wernicke encephalopathy*** - This condition is characterized by the classic triad of **ataxia**, **nystagmus**, and **ophthalmoplegia** (often presenting as external ophthalmoplegia), alongside confusion [2]. - It results from a **thiamine (vitamin B1) deficiency** [2], [3], commonly seen in chronic alcoholics or individuals with severe malnutrition. *Myasthenia gravis* - This is an **autoimmune disorder** affecting the neuromuscular junction, leading to fluctuating muscle weakness that worsens with activity [1]. - While it can cause **ophthalmoplegia** (especially ptosis and diplopia), it does not typically present with ataxia or nystagmus. *3rd nerve palsy* - A **third nerve palsy** specifically affects the oculomotor nerve, causing a constellation of symptoms including ptosis, pupillary dilation, and inability to move the eye up, down, or medially. - While it causes **ophthalmoplegia** affecting one eye, it does not typically cause nystagmus or ataxia. *Chronic progressive external ophthalmoplegia* - This is a mitochondrial disorder characterized by **slowly progressive weakness** of the extraocular muscles, leading to bilateral ptosis and limitation of eye movements. - It causes a specific type of **ophthalmoplegia** but is not typically associated with nystagmus or prominent ataxia.
Question 553: Madarosis is seen in ?
- A. None of the options
- B. Addison's disease
- C. Acromegaly
- D. Hypothyroidism (Correct Answer)
Explanation: ***Hypothyroidism*** - **Madarosis**, specifically the loss of the **outer third of the eyebrows**, is a classic sign of **hypothyroidism** due to decreased thyroid hormone levels affecting hair follicle growth [1]. - Other common symptoms include **fatigue**, **weight gain**, **cold intolerance**, and **dry skin**. *Addison's disease* - This condition involves **adrenal insufficiency**, primarily causing symptoms like **hyperpigmentation**, low blood pressure, and fatigue. - **Hair loss** is generally not a prominent feature, and madarosis is not typically seen. *Acromegaly* - Characterized by excessive **growth hormone** production, leading to enlargement of hands, feet, and facial features. - While it can cause some changes in hair texture, **madarosis** is not a common clinical manifestation. *None of the options* - This option is incorrect because **Hypothyroidism** is a direct cause of madarosis due to its impact on **hair follicle metabolism** [1]. - The other conditions listed do not typically present with this specific type of eyebrow hair loss.
Ophthalmology
4 questionsWhat condition is characterized by cherry red spot at the macula with retinal whitening?
Most common cause of bilateral optic atrophy is:
Massaging of nasolacrimal duct is done in ?
The reduced effect of low astigmatism in dim light is primarily due to:
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 551: What condition is characterized by cherry red spot at the macula with retinal whitening?
- A. CRVO
- B. CRAO (Correct Answer)
- C. Diabetic retinopathy
- D. Syphilitic retinopathy
Explanation: ***CRAO*** - **Central retinal artery occlusion (CRAO)** is characterized by **sudden, profound, painless monocular vision loss**. - The classic funduscopic finding is a **cherry-red spot at the macula** with diffuse **retinal whitening** due to ischemia. *CRVO* - **Central retinal vein occlusion (CRVO)** presents with **painless vision loss** but typically shows **hemorrhages**, **dilated tortuous veins**, and **cotton wool spots** on funduscopic exam. - It does not usually cause retinal whitening or a cherry-red spot. *Diabetic retinopathy* - **Diabetic retinopathy** is characterized by **microaneurysms**, **hemorrhages**, **hard exudates**, and **cotton wool spots**, and can lead to neovascularization. - It does not present with acute retinal whitening or a cherry-red spot in the macula. *Syphilitic retinopathy* - **Syphilitic retinopathy** can cause a variety of presentations, including **retinal vasculitis**, **chorioretinitis**, and **optic neuritis**. - It does not typically manifest as a cherry-red spot with diffuse retinal whitening at the macula.
Question 552: Most common cause of bilateral optic atrophy is:
- A. Intracranial tumor
- B. Nutritional deficiency (B12/folate) (Correct Answer)
- C. Hereditary optic neuropathy
- D. Toxic optic neuropathy
Explanation: ***Nutritional deficiency (B12/folate)*** - **Nutritional optic neuropathy** due to deficiencies in B vitamins (especially B12, thiamine) and folate is a common cause of bilateral optic atrophy, particularly in **developing countries** and in populations with **malnutrition or chronic alcoholism**. - These deficiencies impair the **metabolism of retinal ganglion cells** and their axons, leading to symmetric bilateral optic nerve degeneration. - The condition is often **reversible in early stages** with appropriate supplementation. - **Note:** The "most common" cause varies by geographic location, population, and clinical setting. *Hereditary optic neuropathy* - **Leber's hereditary optic neuropathy (LHON)** and **autosomal dominant optic atrophy (ADOA)** are major causes of bilateral optic atrophy, especially in **younger patients**. - LHON typically presents in young males (15-35 years) with **sequential bilateral visual loss**. - These are among the **most common inherited optic neuropathies** and should always be considered in bilateral cases. *Intracranial tumor* - Intracranial tumors typically cause **unilateral optic atrophy** due to direct compression of one optic nerve. - **Bilateral optic atrophy** can occur with **chiasmal or suprasellar tumors** (pituitary adenomas, craniopharyngiomas) but is less common. - Usually presents with **visual field defects** (bitemporal hemianopia) before significant atrophy develops. *Toxic optic neuropathy* - **Toxic optic neuropathies** result from exposure to substances such as **methanol, ethambutol, tobacco-alcohol amblyopia**, or isoniazid. - Can cause bilateral symmetric optic atrophy but are **exposure-dependent** and less prevalent in general population. - **Tobacco-alcohol amblyopia** may overlap with nutritional deficiency.
Question 553: Massaging of nasolacrimal duct is done in ?
- A. Acute dacryocystitis
- B. Congenital dacryocystitis (Correct Answer)
- C. Conjunctivitis
- D. None of the options
Explanation: ***Congenital dacryocystitis*** - **Massaging the nasolacrimal duct** (Crigler massage) is a primary treatment for congenital dacryocystitis to promote the opening of the **valve of Hasner**. - This condition is due to incomplete canalization of the nasolacrimal duct, leading to tearing and discharge in infants. *Acute dacryocystitis* - This is an **acute infection of the lacrimal sac**, and massaging can worsen the condition by spreading the infection. - Treatment typically involves **antibiotics** and, if necessary, incision and drainage of any abscess. *Conjunctivitis* - **Conjunctivitis** is inflammation of the conjunctiva and is not related to obstruction of the nasolacrimal duct. - Massaging the nasolacrimal duct has no therapeutic role in treating conjunctivitis. *None of the options* - This option is incorrect because **congenital dacryocystitis** is a condition where nasolacrimal duct massage is a standard and effective treatment.
Question 554: The reduced effect of low astigmatism in dim light is primarily due to:
- A. Pupil dilatation
- B. Pupil constriction (Correct Answer)
- C. Increased curvature of lens
- D. Decreased curvature of lens
Explanation: ***Pupil constriction*** - In dim light conditions, patients with low astigmatism may experience **reduced symptoms** due to the **pinhole effect** of pupil constriction when they squint or strain to see better. - **Pupil constriction** limits light entry to the central optical zone, reducing the effect of irregular corneal curvature by creating a smaller aperture that acts like a **stenopic slit**. - This **pinhole effect** improves depth of focus and reduces blur from astigmatism by eliminating peripheral aberrant rays. - When viewing in dim light, patients naturally squint to improve clarity, which mimics pupil constriction and reduces astigmatic blur. *Pupil dilatation* - **Pupil dilatation** in dim light would actually *increase* astigmatic symptoms, not reduce them. - A larger pupil allows more peripheral rays to enter the eye, which pass through areas of the lens and cornea with greater refractive error. - This increases the blur circle and worsens the optical quality in uncorrected astigmatism. *Increased curvature of lens* - **Increased lens curvature** (accommodation) increases refractive power but does not correct the unequal curvature of different meridians that defines astigmatism. - This would not specifically reduce astigmatic blur in dim light conditions. *Decreased curvature of lens* - **Decreased lens curvature** reduces refractive power and is associated with relaxed accommodation. - This does not address the fundamental issue of unequal meridional refraction in astigmatism.