Random USMLE Facts volume 2-9

Rahul's Noteblog Notes on USMLE facts, Exam Tips, and USMLE Lab Values Random USMLE Facts volume 2-9

Random USMLE Facts volume 2-9:

USMLE Facts 1	USMLE Facts 2	USMLE Facts 3	USMLE Facts 4	USMLE Facts 5
USMLE Facts 6	USMLE Facts 7	USMLE Facts 8	USMLE Facts 9	USMLE Facts 10

Secondary Causes of Hypertension Chart:

What is sclerosing cholangitis and how does it develop?

It is one of the complications of uncreative colitis. Findings include gallstones and large bile-duct obstruction. Diagnois is made through endoscopic retrograde cholangiopancreatography (ERCP). There may be alternating constriction and dilation of intrahepatic bile ducts.

What are the findings in acute and chronic organ rejection?

• Acute: dense interstitial neutrophil infiltration.
• Chronic: obliterative vascular fibrosis.

How is diagnosis of myasthenia gravis?

Edrophonium (tensilon) test.

What is the exact function of the APC gene in terms of tumor growth?

APC promotes degradation of catenin by phosphorylation via GSK3b preventing apoptosis and allowing accumulated catenin to stimulate cell growth. Thus, deletion or loss-of-funtion of the APC gene can lead to tumors.

Explain the different muscle relaxants:

There are two types: neuromuscular blockers and spasmolytics. Neuromuscular blockers are used during surgery and don't act on the CNS. However, spasmolytics are centrally acting muscle relaxants. When a person experiences a strained muscle, a spasmolytics are used. Furthermore, NSAIDS are also used for pain control. An example of a spasmolytic would be cyclobenzaprine. Cyclobenzaprine is a centrally acting spasmolytic that may cause sleepiness, dry mouth, tachycardia. Furthermore, there may be urinary retention, respiratory depression, wide QRS complex.

Why is arginine administered for hyperammonemia?

Arginine supplies the urea cycle with ornithine and N-acetylglutamate (NAG) required to activate carbamoyl phosphate synthetase. In the end, this leads to the formation of arginosuccinic acid.

What is the cause of erectile dysfunction?

Decreased release of nitric oxide.

Why do anticonvulsants cause neural tube defects?

Anticonvulsants decrease the absorption and increase the metabolism of folate.

What is 'long QT syndrome?'

This is a family condition that leads to increased risk for developing ventricular arrhythmias. Cardiac potassium channels are mutated. Furthermore, antiarrhythmic drugs such as class IA sodium channel blockers may increase risk for torsades de pointes.

In what part of the intestine is most the patient most likely to develop twisted bowel?

Sigmoid colon because it is poorly supported.

What are the findings in disulfiram-like reaction?

Nausea, vomiting, sweating, hyperventilation, tachycardia, vertigo.

Describe the most common form of thyroid carcinoma:

Papillary carcinoma of the thyroid. It is caused by radiation exposure to the thyroid/neck region. Aspiration of the nodule demonstrates small solid balls of neoplastic follicular cells. Begins at age 30-50 and shows female predominance. The carcinoma has excellent prognosis. The tumor may spread to thyroid or cervical lymph nodes.

Striated (smooth) muscle not under voluntary control is present in?

Esophagus.

What effect can untreated hypertension have on arteries and arterioles?

Untreated hypertension can lead to hypertrophy of arteries and arterioles. The arteriolar wall-to-lumen ratio increases.

If a patient falls with outstretched arms, what bone is most likely to be fractured?

Scaphoid bone. There is pain in skin covering the anatomic snuffbox.

USMLE Facts 1	USMLE Facts 2	USMLE Facts 3	USMLE Facts 4	USMLE Facts 5
USMLE Facts 6	USMLE Facts 7	USMLE Facts 8	USMLE Facts 9	USMLE Facts 10

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