Low-Temperature and Solventless Ring-Opening Polymerization of Eutectic Mixtures of l-Lactide and Lactones for Biodegradable Polyesters

Biodegradability is one of the key features for reducing the negative environmental impact of plastic waste disposal; therefore, designing biocompatible polymeric biomaterials with programmable life cycles is urgently needed. Herein, deep eutectic solvent monomers (DESm) composed of l-lactide and various lactones of different molecular weights were formulated to obtain polyesters at low temperatures with the aid of organocatalysts and under solventless conditions. The introduced DESm expand the range of eutectic mixtures capable of undergoing ring-opening polymerization (ROP) to include mixtures of l-lactide with δ-valerolactone and δ-hexalactone. Extending the toolbox for DESm preparation will allow for the design of polyesters with tailored molecular weight and crystallinity, which are conducive to programmable degradability. ROP of DESm carried out at low temperatures and under solventless conditions holds promise for a sustainable framework for preparing biodegradable polymers for biomedical applications.</p

From polymer blends to a block copolymer:Ring-opening polymerization of L-lactide/ε-caprolactone eutectic system

In this work, we provide new insights into the ring-opening polymerization (ROP) of eutectic mixtures of L-lactide and ε-caprolactone that lead to the synthesis of polymer blends and a block copolymer. The influence of a set of parameters is studied to produce polyesters with tunable average-molecular weight, crystallinity, and polymer architectures with controlled degradation profiles. The outcome depends on the selection of organocatalysts, including 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN), a new catalyst for the L-lactide/ε-caprolactone eutectic mixture ROP that enabled increasing the polymerization temperature. The mild polymerization temperatures and solventless conditions stand as green features of the ROP here described to prepare resorbable biomaterials with programmable degradation profiles

From polymer blends to a block copolymer: Ring-opening polymerization of L-lactide/ε-caprolactone eutectic system

In this work, we provide new insights into the ring-opening polymerization (ROP) of eutectic mixtures of L-lactide and ε-caprolactone that lead to the synthesis of polymer blends and a block copolymer. The influence of a set of parameters is studied to produce polyesters with tunable average-molecular weight, crystallinity, and polymer architectures with controlled degradation profiles. The outcome depends on the selection of organocatalysts, including 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN), a new catalyst for the L-lactide/ε-caprolactone eutectic mixture ROP that enabled increasing the polymerization temperature. The mild polymerization temperatures and solventless conditions stand as green features of the ROP here described to prepare resorbable biomaterials with programmable degradation profiles

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P &lt; 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)