Eleven type-I (insulin-dependent) diabetic patients with abnormal changes in left ventricular function in response to cold stress (CS) were investigated to try and determine the cause of these abnormal responses. Resting M-mode echocardiography demonstrated that all 11 patients had normal left ventricular dimensions and wall motion, thereby excluding overt cardiomyopathy. Thallium-201 scintigraphy was used to assess myocardial perfusion during CS and eight patients were found to have perfusion defects during stress which persisted in four. It is possible that CS unmasks evidence of myocardial ischemia but it is also possible that the abnormal responses to CS reflect altered vasomotor reactivity in the diabetic patient, producing coronary spasm. Left ventricular function may be influenced by many factors in diabetes and an abnormal CS test may not necessarily indicate structural disease. Such tests, however, may help in the further understanding of the pathophysiology of heart disease in diabetes.

Adult↗

PubMedDate not supplied

Phagocytic properties of cultured murine trophoblast.

The phagocytic potential of cultured trophoblast from early (ectoplacental cone (EPC); day 7.5 post coitum) and mid-term (placenta; day 12 to 14 post coitum) pregnancy in the mouse has been examined using a variety of test particles and culture conditions. In suspension, small numbers (less than 1 per cent) of large placental trophoblast cells showed limited phagocytic uptake of Staphylococcus aureus but not of opsonized sheep red blood cells (RBCs). In contrast, trophoblast phagocytosis was never seen in monolayer placental cell culture. Placental macrophages consistently exhibited phagocytic uptake of both opsonized sheep RBCs and S. aureus under these conditions. In monolayer culture, EPC trophoblast phagocytosed S. aureus, but there was only limited uptake of RBCs (mouse or sheep) or spermatozoa. When cultured in a three-dimensional matrix (blood and plasma clots), however, EPC trophoblast demonstrated extensive phagocytosis of both RBCs and sperm. These results are discussed with reference to the use of in vitro systems for examining developmental processes, and a possible role for trophoblast phagocytosis in early gestation is proposed.

Animals↗