All of the following occur when B-cells (B-lymphocytes) encounter antigen EXCEPT:

Severe heart wall abnormalities, including hypokinesis (reduced contraction) of the left ventricle would change blood pressure in the vessels. Which of these pressure (s) change(s) (increase/decrease) in pulmonary capillaries given the diagnosis of left ventricular hypokinesis and apical ballooning? Why? How do changes in these pressures lead to pulmonary edema?  

An aerobic endurance athlete is trying to give himself a competitive edge over his opponents. To improve his lactate threshold, what type of training should he engage in, and in what direction would this shift his threshold?

Ejection fraction is defined as how much blood the left ventricle pumps out with each contraction as a percentage of total ventricular volume. The patient’s left ventricular ejection fraction was 20% (normal range: 50-75%). a) Assuming that the total ventricular volume (=end diastolic volume) is 100ml, calculate end systolic volume of the patient and compare it to normal (decreased or increased). b) Heart rate would (decrease or increase) to maintain homeostasis of cardiac output. Include an equation to justify your answer. c) Is her condition takotdubo cardiomyopathy (systolic or diastolic) problem? Is there any other clue to conclude it among her signs?

Each of the following factors would increase peripheral resistance EXCEPT one. Identify the exception.

When the radius of the resistance vessels is increased, which of the following is increased?

If an athlete completes a maximum sprint interval in 10 seconds as part of an interval training workout, which of the following is a recommended length of the rest period before the next sprint?

The pressure differential between the heart and the aorta is least in the

Short Answers (50 points) Please answer questions concisely and write clearly.   A 55-year-old female was admitted to the hospital due to “pounding” in her chest, nausea, and diaphoresis (sweating) that persisted for 40 minutes after a routine jog. The heart rate was 65 beats per minute, and the blood pressure 138/72 mm Hg. Doctors noted that her blood troponin I level was elevated and continued to rise 11 hours later (from 0.055 ng/ml to 0.415 ng/ml; normal range, 0 to 0.045). All other tests were normal with the left ventricular end-diastole pressure, 5 mmHg, and she was discharged with aspirin and a beta-blocker for presumed exercise-related supraventricular tachycardia. Four months later, while she was on a downhill-skiing trip in Vermont, she experienced acute nausea and emesis (vomiting) followed by chest pain and dyspnea (difficulty breathing). The heart rate was 111 beats per minute, the blood pressure was 115/81 mm Hg, the troponin I level was 11 ng/ml, and the white-cell count was 36,100 per cubic millimeter (normal range, 4500 to 11,000). Intravenous infusions of heparin and furosemide (diuretics) were administered at a local emergency department then transferred to the local hospital via helicopter. On the patient’s arrival, the heart rate was 143 beats per minute, the blood pressure was 96/72 mm Hg, and the troponin I level was 4.790 ng/ml (normal range,

Early in her care, she was treated to lower the heart rate. Discuss three drug mechanisms to lower the heart rate, based on three different types of receptors which influence heart rate. Justify the administration of norepinephrine following an episode of hypotension. Specifically, state how the drug impacts contractility, stroke volume, and mean arterial pressure. Be sure to do the following; a) Identify the type of receptor to which norepinephrine binds on a myocardial (contractile) cell. b) Predict intracellular calcium levels after receptor-ligand binding (increase/decrease) and identify two resulting mechanisms that lead to those changes.