Blood Flow Pattern and Anastomotic Compliance for Interrupted versus Continuous Coronary Bypass Grafts

&lt;P&gt;Background: Use of the interrupted coronary anastomosis has largely been abandoned in favor of the more rapid continuous suturing technique. The Coalescent U-CLIP anastomotic device allows the surgeon to create an interrupted distal anastomosis in the same amount of time that it would take to create a continuous anastomosis. This acute bovine study examined the effect of the anastomotic technique on blood flow and vessel wall function. &lt;/P&gt;&lt;P&gt;Methods: End-to-side coronary anastomoses were created in an open chest bovine model using the left and right internal thoracic arteries and the left anterior descending coronary artery. All other variables except suturing technique were carefully controlled. In each animal, one anastomosis was completed using a continuous suturing technique and the other was performed in an interrupted fashion using the Coalescent U-CLIP anastomotic device. Volumetric flow curves through each graft were analyzed using key indicators of anastomotic quality, and anastomotic compliance was evaluated using intravascular ultrasound. Luminal castings were created of each vessel to examine the interior surface of each anastomosis for constrictions and deformities. &lt;/P&gt;&lt;P&gt;Results: The interrupted anastomoses created with the Coalescent U-CLIP anastomotic device showed significant differences with respect to anastomotic compliance, pulsatility index, peak flow, and percentage of diastolic flow. The cross-sectional area and degree of luminal deformity were also different for the two suturing techniques. &lt;/P&gt;&lt;P&gt;Conclusions: In this acute bovine model, interrupted coronary anastomoses demonstrated superior geometric consistency and greater physiologic compliance than did continuously sutured anastomoses. The interrupted anastomosis also caused fewer disturbances to the flow waveform, behaving similarly to a normal vessel wall. The combination of these effects may influence both acute and long-term patency of the coronary bypass grafts.&lt;/P&gt;</jats:p

A longitudinal study of the relation of lead in blood to lead in air concentrations among battery workers.

The relation between lead in air (PbA) and lead in blood (PbB), concentrations was investigated among 44 workers in five major operations in a United States high volume, lead acid battery plant. The study covered a 30 month period in which workers received frequent PbA and PbB determinations, workers remained in a single job, and PbA concentrations averaged below the US Occupational Safety and Health Administration (OSHA) permissible exposure limit of 50 micrograms/m3. In both univariate and multivariable linear regressions, longitudinal analyses averaging PbA concentrations over the 30 month study period appeared superior to cross sectional analyses using only six month PbA averages to model PbB concentrations. The covariate adjusted coefficient (alpha value) for PbA (mu/m3) in models of PbB (micrograms/100 g) was 1.14. This figure is strikingly higher than that reported in previous studies in the lead acid battery industry in all of which PbA concentrations were substantially higher than in the current study. Plausible explanations for the difference in alpha values include non-linearity of the PbA-PbB curve, a higher fraction of large size particulate associated with higher PbA concentrations, survivor bias among workers exposed to higher PbA concentrations, and the cross sectional designs of most previous studies. Despite previously reported problems with the model used by OSHA to predict PbA-PbB relations, the findings of this study are in good agreement with the predictions of that model

Neue Einsatzmoeglichkeiten nativer Oele und Fette als Chemierohstoffe. Teilvorhaben 3, Thema 1: Endstaendige Funktionalisierung gesaettigter Fettsaeuren Abschlussbericht

Chlorination, oxidation with nitric acid and ozonization of fatty acids adsorbed on different materials (Al_2O_3, SiO_2, BaSO_4) were studied with respect to regioselective chemical CH oxidation and compared with the Fe (II)-catalized fatty acid oxidation by amine N-oxides in the presence of trifluoroacetic acid. Hydroxylation with amine N-oxides yields the highest product selectivity and regionalselectivity with respect to terminal hydroxyfatty acids. Dry ozonolysis of fatty acids adsorbed on silica gel yields 80-90% oxofatty acids. By fermentation of oleic acid with candida tropicalis 50% cis-9-octadecene-1,18-diacid is obtained. Microbial palmitin acid oxidation could be improved by batch fermentation to yield 35-47% hexadecane-diacid. (WEN)Available from TIB Hannover: F96B449+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman