Identification of polyhydroxyalkanoates in Halococcus and other haloarchaeal species

Polyhydroxyalkanoates (PHAs) are accumulated in many prokaryotes. Several members of the Halobacteriaceae produce poly-3-hydroxybutyrate (PHB), but it is not known if this is a general property of the family. We evaluated identification methods for PHAs with 20 haloarchaeal species, three of them isolates from Permian salt. Staining with Sudan Black B, Nile Blue A, or Nile Red was applied to screen for the presence of PHAs. Transmission electron microscopy and 1H-nuclear magnetic resonance spectroscopy were used for visualization of PHB granules and chemical confirmation of PHAs in cell extracts, respectively. We report for the first time the production of PHAs by Halococcus sp. (Halococcus morrhuae DSM 1307T, Halococcus saccharolyticus DSM 5350T, Halococcus salifodinae DSM 8989T, Halococcus dombrowskii DSM 14522T, Halococcus hamelinensis JCM 12892T, Halococcus qingdaonensis JCM 13587T), Halorubrum sp. (Hrr. coriense DSM 10284T, Halorubrum chaoviator DSM 19316T, Hrr. chaoviator strains NaxosII and AUS-1), haloalkaliphiles (Natronobacterium gregoryi NCMB 2189T, Natronococcus occultus DSM 3396T) and Halobacterium noricense DSM 9758T. No PHB was detected in Halobacterium salinarum NRC-1 ATCC 700922, Hbt. salinarum R1 and Haloferax volcanii DSM 3757T. Most species synthesized PHAs when growing in synthetic as well as in complex medium. The polyesters were generally composed of PHB and poly-ß-hydroxybutyrate-co-3-hydroxyvalerate (PHBV). Available genomic data suggest the absence of PHA synthesis in some haloarchaea and in all other Euryarchaeota and Crenarchaeota. Homologies between haloarchaeal and bacterial PHA synthesizing enzymes had indicated to some authors probable horizontal gene transfer, which, considering the data obtained in this study, may have occurred already before Permian times

Unleashing excellence: using a project management approach to effectively implement a simulation curriculum to improve residents’ preparedness

Abstract Background Integrating innovative, simulation-based training programs into medical curricula frequently encounters familiar challenges, including scepticism, limited faculty time, and financial constraints. Recognized for its success in business projects, the Harvard Project Management Theory emerges as a promising approach to optimizing the implementation process and achieving sustainable success. This study endeavours to elucidate the application of project management theory in our implementation process and assess its impact on the clinical preparedness of novice residents. Methods The research utilized a structured four-phase implementation strategy—Planning, Build-up, Execution, and Closing—to develop a simulation-based education curriculum. Incorporating project management tools like project charters and risk management tools played a crucial role in facilitating the effective implementation of standardized processes and improved clinical outcomes. Essential components of this innovative management approach encompass stakeholder engagement, milestone definition, and the alignment of institutional policies and processes. Results A collective of 395 residents actively engaged in eight monthly simulation-based events, reflecting an average participation rate of 39 residents per lecture (± 19). A noteworthy enhancement was observed in the average rating for knowledge gain, with a significant improvement from 5.9/10 to 8.8/10 (p = 0.0001). Participants highlighted the program’s considerable impact on future clinical practice (4.7/5) and teamwork (4.8/5) as particularly valuable aspects. The introduction of a novel organizational structure received favourable feedback from faculty members, with a notable rating of 4.8/5 for predictive time planning. Qualitative insights from the evaluation highlighted the significance of targeted incentive schemes in optimizing the implementation process. Conclusion This project underscores the constructive influence of project management principles in designing simulation-based curricula, explicitly focusing on stakeholder engagement, faculty motivation, and data utilization. Adopting the Harvard Project Management Approach emerges as a catalyst for heightened success in curriculum design, contributing to enhanced emergency preparedness among novice residents. The positive outcomes observed in this study provide valuable insights for future implementations, offering a foundation for refining and optimizing medical education programs to meet the evolving needs of learners and stakeholders alike

Additional file 1 of Unleashing excellence: using a project management approach to effectively implement a simulation curriculum to improve residents’ preparedness

Supplementary Material

Is prolonged infusion of piperacillin/tazobactam and meropenem in critically ill patients associated with improved pharmacokinetic/pharmacodynamic and patient outcomes? An observation from the Defining Antibiotic Levels in Intensive care unit patients (DALI) cohort

Objectives: We utilized the database of the Defining Antibiotic Levels in Intensive care unit patients (DALI) study to statistically compare the pharmacokinetic/pharmacodynamic and clinical outcomes between prolonged- infusion and intermittent-bolus dosing of piperacillin/tazobactam and meropenem in critically ill patients using inclusion criteria similar to those used in previous prospective studies. Methods: This was a post hoc analysis of a prospective, multicentre pharmacokinetic point-prevalence study (DALI), which recruited a large cohort of critically ill patients from 68 ICUs across 10 countries. Results: Of the 211 patients receiving piperacillin/tazobactam and meropenem in the DALI study, 182 met inclusion criteria. Overall, 89.0% (162/182) of patients achieved the most conservative target of 50% fT 65MIC (time over which unbound or free drug concentration remains above the MIC). Decreasing creatinine clearance and the use of prolonged infusion significantly increased the PTA for most pharmacokinetic/pharmacodynamic targets. In the subgroup of patients who had respiratory infection, patients receiving \u3b2-lactams via prolonged infusion demonstrated significantly better 30 day survival when compared with intermittent-bolus patients [86.2% (25/29) versus 56.7% (17/30); P=0.012]. Additionally, in patients with a SOFA score of 65 9, administration by prolonged infusion compared with intermittent-bolus dosing demonstrated significantly better clinical cure [73.3% (11/15) versus 35.0% (7/20); P=0.035] and survival rates [73.3% (11/15) versus 25.0% (5/20); P=0.025]. Conclusions: Analysis of this large dataset has provided additional data on the niche benefits of administration of piperacillin/tazobactam and meropenem by prolonged infusion in critically ill patients, particularly for patients with respiratory infection