Impact of hexamine addition to a nitrite-based additive on fermentation quality, Clostridia and Saccharomyces cerevisiae in a white lupin-wheat silage.

BACKGROUND: Nitrite and hexamine are used as silage additives because of their adverse effects on Clostridia and Clostridia spores. The effect of sodium nitrite and sodium nitrite/hexamine mixtures on silage quality was investigated. A white lupin-wheat mixture was treated with sodium nitrite (NaHe0) (900 g t-1 forage), or mixtures of sodium nitrite (900 g t-1 ) and hexamine. The application rate of hexamine was 300 g t-1 (NaHe300) or 600 g t-1 (NaHe600). Additional treatments were the untreated control (Con), and formic acid (FA) applied at a rate of 4 L t-1 (1000 g kg-1 ). RESULTS: Additives improved silage quality noticeably only by reducing silage ammonia content compared with the control. The addition of hexamine to a sodium nitrite solution did not improve silage quality compared with the solution containing sodium nitrite alone. The increasing addition of hexamine resulted in linearly rising pH values (P < 0.001) and decreasing amounts of lactic acid (P < 0.01). Sodium nitrite based additives were more effective than formic acid in preventing butyric acid formation. Additives did not restrict the growth of Saccharomyces cerevisiae compared to the control. CONCLUSION: The addition of hexamine did not improve silage quality compared with a solution of sodium nitrite. © 2018 Society of Chemical Industry.

Comparison of transcatheter aortic valve implantation with the newest-generation Sapien 3 vs. Direct Flow Medical valve in a single center cohort.

BACKGROUND: The latest generation transcatheter heart valves including Edwards Sapien 3 (ES3) and Direct Flow Medical (DFM) were designed to allow precise implantation at the intended position and to minimize prosthesis dysfunction as well as procedural complications. Our aim was to compare short-term functional and clinical outcomes of these 2 transcatheter aortic valve systems. METHODS: Of 174 patients undergoing transfemoral transcatheter aortic valve implantation (TAVI) at our institution between August 2013 and June 2015, 113 were treated with ES3 and 61 with DFM. Device success, residual aortic regurgitation and early safety endpoints were defined according to the updated VARC-2 criteria and prespecified as primary endpoints. RESULTS: Patients treated with ES3 had a significantly higher rate of procedural success (ES3 94% vs. DFM 79%, p=0.005), mainly driven by lower postprocedural gradients (ES3 8.6±0.5mmHg vs. DFM 14.6±1.4mmHg by invasive recordings; p=0.00012) and no incidence of more than mild aortic regurgitation. The occurrence of safety endpoints at 30days was low and comparable in the DFM vs. ES3 group (ES3 88% vs. DFM 95% of patients without endpoints, p=0.26). No significant differences were observed in 30day mortality, stroke or the incidence of new permanent pacemaker implantation. CONCLUSIONS: These single-center experience data show a higher rate of device success for ES3 treated patients, while 30day safety outcome was similar in both groups. Long-term follow-up and larger scale multicenter experience will have to assess possible effects of these observations on long-term clinical outcomes.

Transcatheter aortic valve implantation with the new-generation Evolut R™: Comparison with CoreValve® in a single center cohort.

BACKGROUND: The Medtronic Evolut R (EVR) is a novel transcatheter heart valve designed to allow precise implantation at the intended position and to minimize prosthesis dysfunction as well as procedural complications. Our aim was to compare short-term functional and clinical outcomes of the new EVR with the established Medtronic CoreValve (CV) system. METHODS AND RESULTS: Of 151 patients undergoing transfemoral transcatheter aortic valve implantation with a self-expanding valve at our institution between January 2013 and January 2016, 86 were treated with EVR and 65 with CV. Patients treated with EVR had a significantly lower rate of more-than-mild aortic regurgitation and a higher rate of device success. Recapture maneuvers to optimize valve deployment were performed in 22.1% of the EVR procedures. Transvalvular post-procedural gradients were slightly higher in the EVR group, while no differences were observed in the incidence of safety endpoints at 30 days, vascular complications, or need for permanent pacemaker implantation following asystole or complete atrioventricular block. CONCLUSIONS: These initial single-center experience data on the short-term outcomes after EVR valve implantation show a substantially reduced rate of more-than-mild paravalvular regurgitation and higher device success, while 30-day safety outcomes were similar to the CV system. Clinical outcome data from long-term follow-up and larger scale multicenter experience are now necessary.

Emboli formation rather than inflammatory mediators are responsible for increased cerebral water content after conventional and assisted beating-heart myocardial revascularization in a porcine model.

BACKGROUND AND PURPOSE: Emboli and proinflammatory mediators are suspected of generating cerebral edema after coronary surgery. In contrast to cardiopulmonary bypass (CPB), off-pump coronary artery bypass surgery (OPCAB) reduces microemboli count and proinflammatory mediator release but carries the risk of hemodynamic instability. A microaxial blood pump can augment cardiac output. METHODS: Coronary bypasses were constructed in pigs with CPB and cardioplegia (n=9), OPCAB (n=9), or blood-pump support CAB (n=9). Nine animals underwent sham operation. Embolus count was monitored and regional cerebral blood flow was assessed with microspheres in 21 brain specimens per animal (n=189 per group). Interleukins 6 and 8 and tumor necrosis factor-alpha concentrations were determined. These variables were studied before, during, and for 4 hours after surgery. Finally, cerebral water content was determined. RESULTS: During CPB and blood-pump CAB, a significant number of emboli were counted in contrast to OPCAB and controls (P<0.05). During CPB, regional cerebral blood flow was affected (32 of 189) and showed reactive hyperemia except in 10 specimens after aortic cross-clamp release. This impairment persisted in 20 specimens. During and after OPCAB, regional cerebral blood flow remained nearly unchanged but showed low flow during (58 of 189) and after (35 of 189) the blood-pump run. A significant increase in proinflammatory mediators was observed only in the CPB group. CPB and blood-pump CAB significantly increased cerebral water content (P<0.05). A strong correlation between embolic load and cerebral water content was observed in all groups. No correlation between proinflammatory mediator release and cerebral water content was detected. CONCLUSIONS: Emboli formation rather than inflammatory mediators are responsible for increased cerebral water content after conventional and assisted beating-heart myocardial revascularization.