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E Solis

Publications and source records attributed to E Solis.

45 records · Page 3Linked to original sources
PubMedDate not supplied

Quantitation of platelet and fibrinogen-fibrin deposition on components of tissue valves (Ionescu-Shiley) in calves.

With 111In-labeled platelets and 125I-labeled bovine fibrinogen, regional mapping of platelet and fibrinogen deposition on leaflets and sewing rings was obtained. Ten Holstein calves received 25-mm mitral valves (ISLM) and were killed 1, 14, and 30 days after implantation. Twenty-four hours before the calves were killed, 350 to 450 microCi of 111In-labeled platelets and 200 to 250 microCi of 125I-labeled bovine fibrinogen were administered intravenously. The components of the tissue valves, i.e., three leaflets and sewing rings, were separated. Each leaflet was cut into four sections: free edge, central zone, flexion zone, and attachment zone. From the radioactivity in blood, leaflet zones, sewing rings, area of leaflet zones, platelet count, and fibrinogen level in blood, the mean regional density of adherent platelets, fibrinogen-fibrin, and fibrinogen/platelet were calculated. The density of platelets and fibrinogen deposited on the components of the valves decreases with time postimplantation. The number of fibrinogen molecules per platelet is fivefold to 20-fold higher than that of the receptor concentration on platelets on leaflet zones, suggesting the heterogeneity of fibrinogen-fibrin in thrombus and components of the valve.

Animals↗
PubMedDate not supplied

Liver and kidney function in patients undergoing mechanical circulatory support with Jarvik-7 artificial heart as a bridge to transplantation.

Changes in liver and kidney function were reviewed in 32 patients who received a Jarvik-7 total artificial heart (TAH) as a bridge to transplantation. Preoperatively, seven (22%) had significant isolated kidney dysfunction, five (15%) had isolated liver impairment, and 13 (41%) had combined disorder, affecting 25 (78%) of the 32 recipients. Immediately after TAH implantation, vigorous diuresis occurred, and biochemical indices improved in 17 patients: 71% of isolated kidney, 60% of isolated liver, and 38% of combined organ disorder were reversed irrespective of severity in preoperative dysfunction. In contrast, urine output remained poor, and biochemical indices continued to deteriorate in 15 patients regardless of preoperative status; as a result, kidney (28%), liver (17%), and combined organ failure (33%) accounted for a total of 78% of failure in this series. Although preoperative liver and kidney dysfunction were frequent and severe, they did not correlate with postoperative functional recovery and later transplantation. Recipient body size and initial postoperative urine output were found to be the variables discriminating patients with or without subsequent transplantation. Because liver/kidney failure remained as the leading cause of death, knowledge of the underlying cause of the organ failure would increase the success of TAH as a bridge to transplantation.

Acute Kidney Injury↗
PubMedDate not supplied

Effect of diphosphonate binding to collagen upon inhibition of calcification and promotion of spontaneous endothelial cell coverage on tissue valve prostheses.

A noncalcifying drug, aminodiphosphonate, was immobilized on pericardial collagen to inhibit calcification. The parameters of ADP binding were optimized by using labeled tracer. The effects of the detergents, Triton X-100 and sodium dodecyl sulfate, pH, and temperature on ADP binding to collagen in fresh pericardium, and stabilization of ADP-collagen bond by borohydride (BH) reduction, were optimized. These studies indicate that pretreatment of pericardium with SDS and TX-100 increases ADP binding three- to fivefold. Three-step cross-linking via Schiff-base reactions between collagen, ADP, and cross-linking via Schiff-base reactions between collage, ADP, and glutaraldehyde gives a high value of 30 to 35 molecules of ADP per collagen in pericardium. Twenty-five millimeter tissue valves were made with detergent (1% SDS, 1% TX-100) treated ADP-bound pericardium and implanted in the mitral annuli in calves, which were killed at 60 days post implantation. Regional calcium deposition was measured with atomic absorption spectrometry. The calcium level (micrograms/mg of tissue) in components of control and four processed valves were determined. Regional platelet deposition on zones of leaflets and components of tissue valves were quantified with 111In-labeled autologous platelets. The calcium levels in thrombus and flexion zones of treated valves are lower than that in the control valve. SEM studies of leaflet surfaces at 60 days indicate that these treatment processes reduce calcification and promote spontaneous cell coverage on leaflets around the smooth surface of the outflow tract.

Animals↗
PubMedDate not supplied

High energy phosphates and catecholamine stores after prolonged ex vivo heart preservation.

Previously, we have demonstrated that hearts preserved ex vivo for 12 hours maintain normal hemodynamic performance after orthotopic transplantation. To complete our studies of these preserved hearts, we evaluated myocardial metabolism by determining high energy phosphate levels and catecholamine concentrations in 22 canine hearts. Group I was the control group in which six hearts were given cold cardioplegic solution; full thickness biopsies were taken from the myocardium in two areas of the right and left ventricles and septum; and adenosine triphosphate, adenosine diphosphate, adenosine monophosphate, creatine phosphate, and catecholamines were determined. Group II, in which the hearts were preserved 12 hours, had eight hearts that were stopped with cold cardioplegic solution, excised, and then preserved in an ex vivo state with a 32 degrees C modified blood perfusate. After a 12-hour perfusion period, the hearts were stopped and biopsies taken. Group III involved cold ischemia and had six hearts that were stopped with cardioplegic solution, excised, opened, flushed, and stored for 2.5 hours at 2 degrees to 4 degrees C. Biopsies were obtained as in groups I and II. Adenosine triphosphate levels were slightly reduced in the 12 hour preserved heart when compared with the control group and the heart in the cold ischemia group preserved for 2.5 hours (p less than 0.01). Creatine phosphate levels were significantly elevated after 12 hour preservation when compared with groups I and III (p less than 0.01). Hearts preserved by cold ischemia also had a reduction (p = 0.03) of creatine phosphate when compared with the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenine Nucleotides↗
PubMedDate not supplied

Early and late comparison of umbilical vein and PTFE grafts in control and piroxicam-treated dogs.

For comparative analysis of small vessel prostheses, 78 dogs underwent femoral artery replacement with autogenous vein, polytetrafluoroethylene (PTFE) or human umbilical vein (HUV) grafts. Thirty-six animals received antiplatelet therapy with piroxicam orally once a day. Three-hour deposition of 111In-labeled platelets was less on HUV than on PTFE grafts but still greater than on autogenous vein grafts. Accordingly, 3-hour patency rates were lowest with PTFE and highest with autogenous vein, although the difference between HUV and PTFE grafts was not statistically significant. One month following implantation, PTFE grafts had a higher patency rate than HUV grafts (p less than 0.05). Treatment with piroxicam decreased 3-hour platelet deposition, improved 1-month patency of both PTFE (p less than 0.05) and HUV (p less than 0.01) grafts, and decreased pseudointimal thickening on PTFE grafts (p less than 0.01). This experimental study did not demonstrate any clearcut difference in the performance of PTFE and HUV grafts. Piroxicam treatment improved the results with both grafts, which would justify future clinical trials with this simple antiplatelet regimen.

Animals↗