Functional changes in long-term incubated rat precision-cut lung slices.

BACKGROUND: Respiratory diseases represent a global health burden. Because research on therapeutic strategies of airway diseases is essential, the technique of precision-cut lung slices (PCLS) has been developed and widely studied. PCLS are an alternative ex vivo model and have the potential to replace and reduce in vivo animal models. So far, the majority of studies was conducted with short-term cultivated PCLS (≤ 72 h). As there is large interest in research of chronic diseases and chronic toxicity, feasibility of cultivating human PCLS long-term over 2 weeks and recently over 4 weeks was investigated by another research group with successful results. Our aim was to establish a model of long-term cultivated rat PCLS over a period of 29 days. METHODS: Rat PCLS were cultured for 29 days and analysed regarding viability, histopathology, reactivity and gene expression at different time points during cultivation. RESULTS: Cultivation of rat PCLS over a 29-day time period was successful with sustained viability. Furthermore, the ability of bronchoconstriction was maintained between 13 and 25 days, depending on the mediator. However, reduced relaxation, altered sensitivity and increased respiratory tone were observed. Regarding transcription, alteration in gene expression pattern of the investigated target genes was ascertained during long-term cultivation with mixed results. Furthermore, the preparation of PCLS seems to influence messenger ribonucleic acid (mRNA) expression of most target genes. Moreover, the addition of fetal bovine serum (FBS) to the culture medium did not improve viability of PCLS. In contrast to medium without FBS, FBS seems to affect measurements and resulted in marked cellular changes of metaplastic and/or regenerative origin. CONCLUSIONS: Overall, a model of long-term cultivated rat PCLS which stays viable for 29 days and reactive for at least 13 days could be established. Before long-term cultivated PCLS can be used for in-depth study of chronic diseases and chronic toxicity, further investigations have to be made.

Implementing an intensified antibiotic stewardship programme targeting daptomycin use in orthopaedic surgery: a cost-benefit analysis from the hospital perspective.

BACKGROUND: Hospital antibiotic stewardship (ABS) programmes offer several evidence-based tools to control prescription rates of antibiotics in different settings, influence the incidence of nosocomial infections and to contain the development of multi-drug-resistant bacteria. In the context of endoprosthetic surgery, however, knowledge of core antibiotic stewardship strategies, comparisons of costs and benefits of hospital ABS programmes are still lacking. MATERIALS AND METHODS: We identified a high daptomycin use for the treatment of methicillin-sensitive staphylococcal infections as a potential target for our ABS intervention. In addition, we endorsed periprosthetic tissue cultures for the diagnosis of PJI. Monthly antibiotic use data were obtained from the hospital pharmacy and were expressed as WHO-ATC defined daily doses (DDD) and dose definitions adapted to local guidelines (recommended daily doses, RDD), normalized per 1000 patient days. The pre-intervention period was defined from February 2012 through January 2014 (24 months). The post-intervention period included monthly time points from February 2014 to April 2015 (15 months). For a basic cost-benefit analysis from the hospital perspective, three cost drivers were taken into account: (1) the cost savings due to changes in antimicrobial prescribing; (2) costs associated with the increase in the number of cultured tissue samples, and (3) the appointment of an infectious disease consultant. Interrupted time-series analysis (ITS) was applied. RESULTS: Descriptive analysis of the usage data showed a decline in overall use of anti-infective substances in the post-intervention period (334.9 vs. 221.4 RDDs/1000 patient days). The drug use density of daptomycin dropped by -75 % (51.7 vs. 12.9 RDD/1000 patient days), whereas the utilization of narrow-spectrum penicillins, in particular flucloxacillin, increased from 13.8 to 33.6 RDDs/1000 patient days. ITS analysis of the consumption dataset showed significant level changes for overall prescriptions, as well as for daptomycin (p < 0.001) and for narrow-spectrum penicillins (p = 0.001). The total costs of antibiotic consumption decreased by an estimated € 4563 per month (p < 0.001), and around 90 % of these savings were linked to a decrease in daptomycin consumption. Overall, the antibiotic stewardship programme was beneficial, as monthly cost savings of € 2575 (p = 0.005) were achieved. INTERPRETATION: In this example of large endoprosthetic surgery department in a community-based hospital, the applied hospital ABS programme targeting daptomycin use has shown to be feasible, effective and beneficial compared to no intervention.

Incorporating Older Adults as "Trained Patients" to Teach Advance Care Planning to Third-Year Medical Students.

BACKGROUND: Advance care planning (ACP) is a critical component of end-of-life (EoL) care, yet infrequently taught in medical training. OBJECTIVE: We designed a novel curriculum that affords third-year medical students (MS3s) the opportunity to practice EoL care discussions with a trained older adult in the patient's home. DESIGN: Volunteers were instructed as trained patients (TPs) to evaluate MS3s interviewing and communication skills. The MS3s received a didactic lecture and supplemental material about ACP. Pairs of MS3s conducted ACP interviews with TPs who gave verbal and written feedback to students. Student evaluations included reflective essays and pre/postsurveys in ACP skills. SETTINGS AND PARTICIPANTS: A total of 223 US MS3s participated in the curriculum. RESULTS: Qualitative analysis of reflective essays revealed 4 themes: (1) students' personal feelings, attitudes, and observations about conducting ACP interviews; (2) observations about the process of relationship building; (3) learning about and respecting patients' values and choices; and (4) the importance of practicing the ACP skills in medical school. Students' confidence in skills significantly improved in all 7 domains ( P < .001): (1) introduce subject of EoL; (2) define advance directives; (3) assess values, goals, and priorities; (4) discuss prior experience with death; (5) assess expectations about treatment and hospitalization; (6) explain cardiopulmonary resuscitation and outcomes; and (7) deal with own feelings about EoL and providers' limitations. CONCLUSIONS: The use of older adults as TPs in an ACP curriculum provides students an opportunity to practice skills and receive feedback in the nonmedical setting, thereby improving comfort and confidence in approaching these conversations for future patients.