MDS PREP
A patient with severe asthma is prescribed a combination of albuterol and ipratropium. What is the primary mechanism of action for each medication?
(1) Albuterol: beta2-adrenergic agonist; Ipratropium: muscarinic antagonist
(2) Albuterol: muscarinic antagonist; Ipratropium: beta2-adrenergic agonist
(3) Albuterol: beta-adrenergic agonist; Ipratropium: muscarinic antagonist
(4) Albuterol: muscarinic agonist; Ipratropium: beta2-adrenergic antagonist
Albuterol is a beta2-adrenergic agonist that relaxes bronchial smooth muscles, while ipratropium is a muscarinic antagonist that blocks the parasympathetic effects on the airways, leading to bronchodilation.
What is the most common cause of chronic bronchitis?
(1) Smoking
(2) Viral infections
(3) Bacterial infections
(4) Air pollution
Chronic bronchitis is most commonly caused by smoking. It is characterized by chronic inflammation of the bronchial tubes, leading to excess mucus production and coughing. Other causes include long-term exposure to irritants like air pollution and repeated respiratory infections.
The pathogenesis of hypocromic anaemia in lead poisoning is due to
1. Inhibition of enzymes involved in heme biosynthesis
2. Binding of lead to transferrin, inhibiting transport of iron
3. Binding of lead to cell membrane of erythroid precursors
4. Binding of lead to ferretin inhibiting their breakdown into hemosiderin
Oral Medicine Answer: 1
Which is not a feature of Adamantinoma?
1) More common in males
2) Soap-bubble appearance on X-ray
3) Uncontrolled local growth
4) Commonest site maxilla
Oral Medicine Answer: 4
Commonest site maxilla
a. Adamantinoma is a rare tumor arising from the diaphysis of the long bone.
b. The most common long bone affected by adamantinoma is TIBIA.
c. In head and neck , the most common bone affected by adamantinoma is MANDIBLE.
d. In mandible, the most common site is the region of 3RD MOLAR.
e. Classic adamantinomas usually occur in patients older than 20 years, whereas
differentiated adamantinomas occur almost exclusively in patients younger than
20 years.
f. In addition, the 2 classifications of adamantinomas have distinct
radiographic and histologic differences.
g. Patients with adamantinomas present with variable signs and symptoms; most
commonly, they report pain and swelling.
h. The tumor is slow growing, and patients may describe discomfort lasting
months to years.
i. Treatment options for adamantinoma are surgical and include either marginal
or en bloc resection.
j. Unfortunately, neither radiation therapy nor chemotherapy has been proven
effective in the treatment of this insidious tumor.
k. The investigation of choice for adamantinoma is CT SCAN which shows cortical
destruction involving the diaphysis of the bone with surrounding periosteal
reaction.
l. On x ray there is a characteristic SOAP BUBBLE appearance.
What is the primary defect in familial hypokalemic periodic paralysis?
1) Marked increase in muscle potassium permeability
2) Marked decrease in muscle sodium permeability
3) Marked decrease in muscle potassium permeability
4) Impaired sodium-potassium pump function
In familial hypokalemic periodic paralysis, the primary defect is a decrease in muscle potassium permeability, leading to a reduced efflux of potassium from muscle cells.
What is the prevalence of Huntington's disease in the general population?
(1) 1 in 1000
(2) 1 in 10,000
(3) 1 in 100,000
(4) 1 in 1,000,000
Huntington's disease is a relatively rare genetic disorder with a prevalence of approximately 1 in 10,000 individuals. It is an autosomal dominant condition, meaning that a person only needs to inherit one copy of the mutated gene from a parent to develop the disease. The onset is typically in the fourth or fifth decade of life, and it is characterized by chorea, behavioral disturbances, and progressive cognitive decline.
What is the treatment for respiratory alkalosis?
1) Inhalation of carbon dioxide
2) Injection of sodium bicarbonate
3) Ingestion of antacids
4) Increase in respiratory rate
The treatment for respiratory alkalosis typically involves correcting the underlying cause. However, if symptoms are severe, inhalation of a small amount of carbon dioxide can be administered.
What is the primary target of antifungal agents such as nystatin and clotrimazole in treating oral candidiasis?
(1) Sterols in the fungal cell membrane
(2) Lipids in the fungal cell membrane
(3) Proteins in the fungal cell membrane
(4) Carbohydrates in the fungal cell membrane
Nystatin and clotrimazole target ergosterol in the fungal cell membrane, leading to increased permeability and death of the fungal cells. This mechanism is specific to fungal cells and does not harm human cells, which lack ergosterol in their membranes.