Cell injury Practice Questions

Question 1

One hour after being admitted to the hospital for sharp, acute chest pain and diaphoresis, a 55-year-old woman with type 2 diabetes mellitus loses consciousness in the emergency department. There are no palpable pulses. Chest compressions are started. The patient has a history of breast cancer that was surgically treated 4 years ago. Prior to admission, the patient was on a long bus ride to visit her sister. Her medications include tamoxifen, atorvastatin, metoprolol, metformin, and insulin. Serum troponin levels are elevated. The cardiac rhythm is shown. Which of the following is the most appropriate next step in management?

Accepted Answer

Defibrillation

Answer

Coronary angiography

Answer

Intravenous dextrose therapy

Answer

Intravenous epinephrine therapy

Answer

Intravenous glucagon therapy

Question 2

Which transport mechanism is primarily responsible for calcium reabsorption in the proximal tubule?

Accepted Answer

Paracellular transport

Answer

Facilitated diffusion

Answer

Active transport

Answer

Antiport with sodium

Question 3

A 52-year-old man is brought to the emergency department by ambulance after a motor vehicle accident. He was an unrestrained passenger who was ejected from the vehicle. On presentation, he is found to be actively bleeding from numerous wounds. His blood pressure is 76/42 mmHg and pulse is 152/min. Attempts at resuscitation fail, and he dies 25 minutes later. Autopsy shows blood in the peritoneal cavity, and histology of the kidney reveals swelling of the proximal convoluted tubule epithelial cells. Which of the following is most likely the mechanism underlying the renal cell findings?

Accepted Answer

Decreased function of the Na+/K+-ATPase

Answer

Decreased activity of caspase 7

Answer

Increased activity of caspase 9

Answer

Increased function of the Na+/K+-ATPase

Answer

Increased activity of caspase 8

Question 4

An investigator is examining tissue samples from various muscle tissue throughout the body. She notices that biopsies collected from a specific site have a high concentration of sarcoplasmic reticulum, mitochondria, and myoglobin; they also stain poorly for ATPase. Additionally, the cell surface membranes of the myocytes in the specimen lack voltage-gated calcium channels. These myocytes are found in the greatest concentration at which of the following sites?

Accepted Answer

Semispinalis muscle

Answer

Ventricular myocardium

Answer

Tunica media

Answer

Lateral rectus muscle

Answer

Glandular myoepithelium

Question 5

A 72-year-old man presents to the emergency department after a fall. The patient was found lying down on the floor in his room in his retirement community. The patient has a past medical history of Alzheimer dementia and a prosthetic valve. His current medications include donepezil and warfarin. His temperature is 97.7°F (36.5°C), blood pressure is 85/50 mmHg, pulse is 160/min, respirations are 13/min, and oxygen saturation is 97% on room air. The patient is started on IV fluids and a type and screen is performed. Laboratory values are ordered as seen below.

Hemoglobin: 13 g/dL
Hematocrit: 39%
Leukocyte count: 5,500 cells/mm^3 with normal differential
Platelet count: 225,000/mm^3

INR: 2.5
AST: 10 U/L
ALT: 12 U/L

A chest radiograph and EKG are performed and are within normal limits. A full physical exam is within normal limits. The patient's vitals are repeated. His temperature is 99.5°F (37.5°C), blood pressure is 110/70 mmHg, pulse is 90/min, respirations are 10/min, and oxygen saturation is 98% on room air. Which of the following is the best next step in management?

Accepted Answer

CT scan

Answer

Urgent blood transfusion

Answer

Fresh frozen plasma

Answer

Exploratory laparoscopy

Answer

Exploratory laparotomy

Question 6

A 31-year-old woman scrapes her finger on an exposed nail and sustains a minor laceration. Five minutes later, her finger is red, swollen, and painful. She has no past medical history and does not take any medications. She drinks socially with her friends and does not smoke. The inflammatory cell type most likely to be prominent in this patient's finger has which of the following characteristics?

Accepted Answer

Segmented nuclei

Answer

Dramatically expanded endoplasmic reticulum

Answer

Large cell with amoeboid movement

Answer

Multiple peripheral processes

Answer

Dark histamine containing granules

Question 7

A 56-year-old man presents to the emergency room with severe substernal chest pain associated with a 2-hour history of breathlessness and sweating. An electrocardiogram shows an ST-segment elevation myocardial infarction. Cardiac enzyme levels confirm a diagnosis of acute myocardial infarction. The patient is rushed to the catheter lab for angioplasty with stenting. The patient complains of recurrent chest pain in the ICU 56 hours post-angioplasty. Which of the following enzymes facilitates the patient’s diagnosis based on his current symptoms?

Accepted Answer

Creatine kinase (CK)-MB

Answer

Creatine kinase – MM

Answer

Troponin T

Answer

Troponin I

Answer

Lactate dehydrogenase (LDH)

Question 8

A 73-year-old man with coronary artery disease and hypertension is brought to the emergency department by ambulance 90 minutes after the acute onset of substernal chest pain and dyspnea. He has smoked 2 packs of cigarettes daily for 52 years. Shortly after arriving at the hospital, he loses consciousness and is pulseless. Despite attempts at cardiopulmonary resuscitation, he dies. Examination of the heart at autopsy shows complete occlusion of the left anterior descending artery with a red thrombus overlying a necrotic plaque. Which of the following pathophysiologic mechanisms is most likely responsible for this patient's acute coronary condition?

Accepted Answer

Secretion of matrix metalloproteinases

Answer

Influx of lipids into the endothelium

Answer

Release of platelet-derived growth factor

Answer

Type III collagen deposition

Answer

Proliferation of smooth muscle cells

Question 9

A 42-year-old man with systolic heart failure secondary to amyloidosis undergoes heart transplantation. The donor heart is obtained from a 17-year-old boy who died in a motor vehicle collision. Examination of the donor heart during the procedure shows a flat, yellow-white discoloration with an irregular border on the luminal surface of the aorta. A biopsy of this lesion is most likely to show which of the following?

Accepted Answer

Lipoprotein-laden macrophages

Answer

Apoptotic smooth muscle cells

Answer

Necrotic cell debris

Answer

Proteoglycan accumulation

Answer

Collagen deposition

Question 10

As part of a clinical research study, microscopic analysis of tissues obtained from surgical specimens is performed. Some of these tissues have microscopic findings of an increase in the size of numerous cells within the tissue with an increase in the amount of cytoplasm, but the nuclei are uniform in size. Which of the following processes shows such microscopic findings?

Accepted Answer

Uterine myometrium in pregnancy

Answer

Liver following partial resection

Answer

Female breasts at puberty

Answer

Ovaries following menopause

Answer

Cervix with chronic inflammation

Cell injury

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Reversible cell injury mechanisms

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Types of necrosis (coagulative, liquefactive, etc.)

Apoptosis pathways

Autophagy mechanisms

Cellular adaptations (atrophy, hypertrophy)

Hyperplasia and metaplasia

Dysplasia

Intracellular accumulations

Pathologic calcification

Cellular aging mechanisms

Ischemia-reperfusion injury

Free radical injury

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