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Continent ileostomy reservoirs were constructed in dogs. Nine to 29 days after formation of the pouches, they were excised together with a loop of adjacent ileum for biochemical and morphological assessment. The villous and epithelial cell heights were reduced, whereas villous width and mitotic index were increased. The mucosa of the pouch was able to absorb phenylalanine and Beta-methyl-glucoside against a concentration gradient, although this absorptive capaciti was lower than that of normal ileum. Similar considerations applied to oxygen consumption. The results indicate that the mucosa of the pouch undergoes transformation, but the intergrity of the epithelial layer is maintained. [ABSTRACT FROM PUBLISHER]

Since Satomura first described an ultrasonic device using the Doppler effect to detect blood flow in 1959, more recent advances in medical engineering have met the need for non-invasive, quantitative measurement of blood flow in peripheral arteries. This goal can now be achieved with the use of a pulsed Doppler combined with an A-mode scan to estimate the angle of the ultrasound beam and the dimensions of the vessel. Although several authors have already published data concerning blood flow volume obtained by continuous wave or pulsed Doppler devices in human peripheral arteries or in animal experiments, the accuracy of their measurements was only correlated with indirect blood flow determinations such as electromagnetic flowmetry or venous occlusion plethysmography. The present study compares the values of blood flow volume obtained by a Multichannel Digital Pulsed Doppler (MDPD) and by direct timed blood collection (DTBC) in the canine common femoral artery. [ABSTRACT FROM AUTHOR]

Balloon angioplasty fails to provide acceptable long-term results for a significant proportion of patients. An intravascular mechanical support, developed with the aim of preventing restenosis and acute closure of diseased arteries after transluminal angioplasty, was implanted in 44 patients (39 male and five female), aged from 35 to 70 years (mean 56 years) with documented restenosis of native coronary artery (41 stents) and bypass grafts (12 stents). In the group of bypass graft patients there was no local restenosis and no major complication. In patients in whom stents were placed in native coronary arteries, the complication rate was higher (two patients died after coronary bypass surgery). One patient died suddenly at home. Except for one patient, in whom a new lesion developed proximally with extension into the stent, no case of restenosis could be observed.Despite the still relatively high complication rate, we feel that stenting may present a rational approach to the unresolved problem of restenosis after coronary angioplasty. [ABSTRACT FROM PUBLISHER]

Short loops of dog small intestine, filled with a buffered glucose solution, were subjected to one hour's total ischaemia by clamping the corresponding mesenteric artery and vein as well as the intestinal wall at each end of the loop. Immediately after the ischaemic period and 24 hours later, their functional capacity, together with that of neighbouring control loops, was determined by studying the absorption of phenylalanine and β-methyl-glucoside and by measuring the levels of Na-K-ATPase in the mucosa. The release of lysosomal enzymes after the ischaemia was studied by gauging the levels of acid phosphatase in the venous blood draining the ischaemic loop. The state of the mucosal microcirculation was investigated by injection of indian ink into the mesenteric artery removal of the loop. Immediately after ischaemia, considerable structural damage was observed in the intestinal mucosa, with desquamation of the villous tips, oedema, vascular stasis, and haemorrhagic infiltration in the lamina propria. No dye was observed in the mucosal capillaries. All transport capacity was abolished, but ATPase levels were unchanged. A significant release of lysosomal enzymes into the venous blood was noted. One day later structural and functional recovery was complete, and vascularization of the villous core was restored. [ABSTRACT FROM PUBLISHER]

Total ischaemia of loops of dog colon was induced by clamping all afferent arteries and the colonic wall for different periods of time. Net sodium transport across the mucosa is abolished after one hour's ischaemia, but Na-K-ATPase levels in microsomal suspensions from the mucosa only fall significantly after two hours' ischaemia. Studies on the functional and morphological recovery of colons subjected to three hours' ischaemia have disclosed an extremely heterogeneous response among the 24 dogs used. Although all parameters were non-existent 24 hours after the intervention, one colon revealed a morphological and functional recovery one week after the operation, whilst two, three, and three out of six recovered after two, three, and four weeks respectively. There was a good correlation between the functional and macroscopic appearance of these recovered loops, though histologically various degrees of disorganization of the mucosa were observed. Among the loops that had no function, there was also a considerable variation in their microscopic structures. The level of Na-K-ATPase in the mucosa was found to be a faithful indicator of the functional state of the tissue, and could be closely correlated with the morphological findings. [ABSTRACT FROM PUBLISHER]