Synthesis of calcium carbonate microspheres via inert gas bubbling for orthopedic applications

Calcium carbonate (CaCO3) microspheres consisting of vaterite polymorph have been widely used in biomedical applications. Specifically, vaterite microspheres having hollow cores showed significant potential in drug delivery, however the spontaneous transformation of vaterite to other polymorphs in aqueous environments reduced its controlled in vivo release capability. In this work, calcite and aragonite microspheres having hollow/porous inner cores were synthesized -for the first time-using sodium dodecyl sulfate (SDS) stabilized nitrogen (N-2) bubbles as CaCO3 template in ethylene glycol (EG) solution and water as the precipitation medium. Results demonstrated that porous aragonite microspheres could be synthesized via N-2 gas incorporation, yet for the synthesis of hollow calcite microspheres, N-2 bubbles had be stabilized with SDS to be utilized as CaCO3 templates. The synthesized aragonite and calcite microspheres were found to be stable up to 5 days in Dulbecco's Modified Eagle's Medium (DMEM), and thus would not allow polymorphic transformation in aqueous environments, while promoting proliferation of human bone cells (hFOB) up to 5 days of culture. These findings -for the first time-identified a viable synthesis route for hollow/porous calcite and aragonite microspheres and indicated their promising use in orthopedic applications

Letter to the Editor Report of surgical correction of a cervicovaginal agenesis case: cervicovaginal reconstruction with pudendal thigh flaps

[No Abstract Available

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 < 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)