A dual thromboxane inhibitor and thromboxane receptor antagonist prevents pig myocardial infarction induced by coronary thrombosis

peer reviewe

In vitro evaluation of the marginal seal of four restoration materials on deciduous molars

The aim of this study was to compare the marginal microleakage of Fuji II LC (A), composite resin Z250 (B), Fuji IX GP (C), and Dyract AP (F) in class V cavities and at the Fuji II LC/Z250 (D) and Fuji IX GP/composite resin Z250 (E) interfaces of an open sandwich technique on deciduous teeth. After thermocycling the mean marginal dye penetration at the enamel junction was 21.6 microns +/- 14.2 for group A; 83.6 microns +/- 32.3 for group B; 7.5 microns +/- 7.5 for group C; 38.7 microns +/- 27.5 for group D, and 0 micron for groups E and F. Mean dye penetration at the cementum junction was 37.1 +/- 20.2 (A); 123 +/- 42.1 (B); 28.7 +/- 17.1 (C); 0 (D); 14.4 +/- 14.4 (E); and 0 (F) microns. No leakage was seen at the junction between Fuji II LC and Z250 (0 micron), whereas a mean leakage of 184 microns between Fuji IX and Z250 was measured. In enamel the best seal was obtained with Dyract AP, but with differences at the limit of significance (P = 0.07). Sealing was significantly worse with Z250 (p = 0.03 versus Fuji II LC; p = 0.006 versus Fuji IX GP; and p = 0.003 versus Dyract AP). In cementum, the comparison between the grouped data Z250-Fuji II LC versus Fuji IX GP-Dyract AP was highly significant (p 0.001), while there was no detectable difference between Z250 and Fuji II LC

Effects of Chronic Volume Overload On Left-ventricular Response To Tachycardia

The aim of the study was to determine the effects of chronic volume overload on the inotropic response of the left ventricle to a change in frequency of stimulation. Ten normal dogs (normal) and eight dogs with a chronic left ventricular (LV) volume overload (aortocaval fistula) were studied by cardiac catheterization after sedation with morphine (1 mg/kg). In normal dogs, increasing heart rate from 122 to 172 beats/min produced insignificant changes in peak +dP/dt (+2%; NS) or (dP/dt)/DP40 (+6%; NS). In volume overload, these indexes increased by 16% (P less than 0.01) and 31% (P less than 0.01), respectively, when heart rate increased from 135 to 173 beats/min. Conversely, the poststimulation potentiation appeared greater in normal than in volume overload; (dP/dt)/DP40 increased by 40% in normal vs. 1% in volume overload (P less than 0.01). These differences between normal and volume overload persisted after propranolol (1 mg/kg) and atropine (0.25 mg) administration. In both groups, AR-L115 BS, a nonsympathomimetic positive inotrope with caffeinelike properties, reduced the inotropic response to tachycardia, thereby normalizing the peak +dP/dt changes in volume overload. We conclude that the positive inotropic effects of tachycardia are enhanced in LV volume overload. Changes in LV compliance or alterations in the cellular mechanisms responsible for the force-frequency phenomenon might explain these findings. </jats:p