A researcher is studying the ability of breast cancer cells to metastasize. Neoplastic cells obtained from 30 patients with stage IV ductal carcinoma of the breast are tagged with a fluorescent antibody. The cells are then inserted into a medium resembling normal human tissue. After 2 weeks, all samples show in vitro hematogenous invasion and migration away from the original site of insertion. Which of the following properties is most likely responsible for the ability of these neoplastic cells to metastasize?
ALoss of cellular polarity
BPresence of fibrous tissue capsule
COverexpression of HER2/neu
DIncrease in N:C ratio
ERelease of matrix metalloproteinase
A 68-year-old woman comes to the physician because of a 3-month history of an oozing, red area above the left ankle. She does not recall any trauma to the lower extremity. She has type 2 diabetes mellitus, hypertension, atrial fibrillation, and ulcerative colitis. She had a myocardial infarction 2 years ago and a stroke 7 years ago. She has smoked 2 packs of cigarettes daily for 48 years and drinks 2 alcoholic beverages daily. Current medications include warfarin, metformin, aspirin, atorvastatin, carvedilol, and mesalamine. She is 165 cm (5 ft 4 in) tall and weighs 67 kg (148 lb); BMI is 24.6 kg/m2. Her temperature is 36.7°C (98°F), pulse is 90/min, respirations are 12/min, and blood pressure is 135/90 mm Hg. Examination shows yellow-brown spots and dilated tortuous veins over the lower extremities. The feet and the left calf are edematous. Femoral, popliteal, and pedal pulses are palpable bilaterally. There is a 3-cm (1.2-in) painless, shallow, exudative ulcer surrounded by granulation tissue above the medial left ankle. There is slight drooping of the right side of the face. Which of the following is the most likely cause of this patient's ulcer?
APeripheral neuropathy
BDrug-induced microvascular occlusion
CChronic pressure
DDecreased arterial blood flow
EVenous insufficiency
A 62-year-old man comes to the physician because of an oozing skin ulceration on his foot for 1 week. He has a history of type 2 diabetes mellitus and does not adhere to his medication regimen. Physical exam shows purulent discharge from an ulcer on the dorsum of his left foot. Pinprick sensation is decreased bilaterally to the level of the mid-tibia. A culture of the wound grows beta-hemolytic, coagulase-positive cocci in clusters. The causal organism most likely produces which of the following virulence factors?
AExotoxin A
BM protein
CP fimbriae
DIgA protease
EProtein A
+ 7 more in the PDF
Browse all chapters