EVIDENCE FOR TRANSFORMATION OF SPLEEN CELLS ONE DAY AFTER INFECTION OF MICE WITH FRIEND LEUKEMIA VIRUS : AUTONOMOUS GROWTH POTENTIAL AND EXPRESSION OF HYBRID-RESISTANCE GENES

Proliferation and erythroid differentiation of transplanted DBA/2 marrow cells and Friend virus-induced leukemic cells were assessed in syngeneic, allogeneic (H-2 compatible), and (BALB/c x DBA/2)F1 hybrid mice (CDF1). Measurements were made 5 days after transplantation of donor cells into nonirradiated or X-irradiated mice by the spleen colony or the 125IUdR-59Fe uptake methods. Growth of DBA/2J (Jackson subline) marrow grafts was poor in irradiated CDF1J hybrids as compared with growth in syngeneic and allogeneic hosts. The DBA/2J transplants proliferated, however, without impairment in irradiated CDF1 hybrids which were the progeny of DBA/2 male parents of other sublines, e.g. DBA/2Ha, DBA/2Cr, and DBA/2Cum. In contrast, tissue-cultured Friend leukemic cells of DBA/2J origin grew deficiently in all CDF1 hybrids tested, regardless of irradiation and of the DBA/2 parent's subline. The growth pattern of transplanted DBA/2J cells was a manifestation of hybrid resistance. The results with DBA/2J and other DBA/2 subline grafts suggested that hybrid histocompatibility alleles were expressed to a greater extent in leukemic than in normal marrow cells, for the former were consistently recognized as "nonself" by CDF1 mice, but not the latter cells. The property of deficient growth in irradiated CDF1Ha hybrids was acquired by DBA/2J hemopoietic cells within 6 hr from infection in vivo with Friend leukemia virus, and persisted during the following 8 days. It was ascribed to enhanced expression of hybrid histocompatibility gene(s) (Hh) induced by the virus. Autonomous growth potential of hemopoietic cells, manifested by proliferation in nonirradiated recipients, was first detected 24 hr from infection, and likewise persisted at the later intervals. At the same time, the infected cells grew deficiently also in nonirradiated CDF1Ha mice. The two irreversible cellular changes were regarded as the earliest signals of virus-induced transformation

Understanding the impact of professional motivation on the workforce crisis in medicine: a rapid review

Background: The NHS is facing a workforce crisis. Responses to date have focused on improving recruitment of staff, but less attention has been paid to retention. Aim: To conduct a rapid review using Rosabeth Moss Kanter's three Ms model of workforce motivation as a sensitising framework to examine the current medical workforce crisis. The work considers how insights from research in other professions offers new thinking for understanding what motivates doctors to continue working. Design & setting: Rapid literature review with secondary analysis of existing research examining reasons for leaving medicine. Method: A systematic search strategy was developed with the aid of an information specialist. The search terms used were: medical professionals, retention, and NHS. The exclusions were: commentaries, non-medical professionals, non-English language, and it was limited to post-1990. The search was applied to three electronic databases, MEDLINE, Embase, and Healthcare Management Information Consortium (HMIC). This produced a dataset describing study design, and factors related to motivation for leaving the medical profession. Comparative thematic analysis distilled core themes explaining the reasons for leaving and their relation to the three Ms model. Results: Of 3389 abstracts identified, screening and assessment produced 82 articles included in the final analysis. Thematic analysis identified four key themes: low morale, disconnect, unmanageable change, and lack of personal and professional support. The themes of mastery, membership, and meaning were substantially present within the dataset. Conclusion: Kanter's three Ms model of motivation can be applied to the medical workforce to understand retention issues. This work supports the development of targeted solutions to tackle the worsening workforce crisis