Recent insights into the signals that control αβ/γδ-lineage fate

Summary:  During thymopoiesis, two major types of mature T cells are generated that can be distinguished by the clonotypic subunits contained within their T-cell receptor (TCR) complexes: αβ T cells and γδ T cells. Although there is no consensus as to the exact developmental stage where αβ and γδ T-cell lineages diverge, γδ T cells and precursors to the αβ T-cell lineage (bearing the pre-TCR) are thought to be derived from a common CD4⁻CD8⁻ double-negative precursor. The role of the TCR in αβ/γδ lineage commitment has been controversial, in particular whether different TCR isotypes intrinsically favor adoption of the corresponding lineage. Recent evidence supports a signal strength model of lineage commitment, whereby stronger signals promote γδ development and weaker signals promote adoption of the αβ fate, irrespective of the TCR isotype from which the signals originate. Moreover, differences in the amplitude of activation of the extracellular signal-regulated kinase- mitogen-activated protein kinase-early growth response pathway appear to play a critical role. These findings will be placed in context of previous analyses in an effort to more precisely define the signals that control T-lineage fate during thymocyte development.     

„Klar bleiben“ – ein Wettbewerb für Schulklassen zur Reduktion des Alkoholkonsums

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Alkohol ist in Deutschland im Jugendalter die populärste Droge. Alkoholpräventionsprogramme, die im Setting Schule...     

Emotionale Erschöpfung und Berufszufriedenheit von Lehrpersonal während der COVID-19-Pandemie

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Die COVID-19-Pandemie hat den beruflichen Alltag von Lehrpersonal erheblich verändert. Das Ziel dieser Arbeit ist es, die...     

Die Generationen Y und Z – Neue Herausforderungen für Führungskräfte im Krankenhaus

Die Anaesthesiologie - In dieser Studie wurden die Studierenden der Generationen Y und Z des Studiengangs Humanmedizin an der Georg-August-Universität Göttingen...     

The Lapidus Arthrodesis: Examining the Effect of the Metatarsal Base Transfixion Screw

The modified Lapidus bunionectomy is a useful and highly powerful procedure for correcting hallux abducto valgus. Traditionally reserved for “severe” deformities, this procedure has seen a recent resurgence in the podiatric community for its unique ability to achieve tri-planar correction of this challenging deformity. Although this procedure has been extensively studied in both biomechanical labs and the clinical arenas, no clear consensus has been achieved regarding optimal fixation for this thought-provoking procedure. The current study examined the differences in strength between commercially available 5-hole locking plates with interfragmentary compression vs a crossed-screw with a third “transfixation” screw construct in a controlled setting. Ten fresh-frozen cadaveric match pair limbs (20 total limbs) were used to complete this study. Ten limbs were randomly assigned to a 3-screw construct. The other 10 contralateral limbs were assigned to a commercially available 5-hole locking plate (5 stainless steel and 5 titanium alloy) with an interfragmentary lag screw construct. The first rays were then isolated and potted into a 4-point bending device. The specimens were loaded to failure in a servohydraulic load frame at a controlled rate. Failure was defined as catastrophic or 3 mm of plantar gapping at the arthrodesis site. The mean maximal load to failure was 310.9 ± 109.4 N for the 3-screw construct. The mean maximal load to failure for the locking plate constructs was 264.1 ± 100.9 N. This difference was not statistically significant (p = .328). These results suggest that a 3-screw construct for Lapidus arthrodesis is as strong as commercially available locking plate constructs.     

Mendelian randomization analysis with survival outcomes

Mendelian randomization (MR) is an established approach for assessing the causal effects of heritable exposures on outcomes. Outcomes of interest often include binary clinical endpoints, but may also include censored survival times. We explore the implications of both the Cox proportional hazard model and the additive hazard model in the context of MR, with a specific emphasis on two‐stage methods. We show that naive application of standard MR approaches to censored survival times may induce significant bias. Through simulations and analysis of data from the Women's Health Initiative, we provide practical advice on modeling survival outcomes in MRs.     

Trauma recidivism

Surgeons have long recognized that a proportion of hospitalized trauma patients present with a history of a previous admission for trauma, termed by the authors as "trauma recidivism." The incidence of trauma recidivism was addressed by a review of 150 consecutive admissions to a level I Trauma Center. This study identifies this subset of trauma patients, establishes their magnitude, and analyzes mechanisms of injury and hospital courses. The implications for those who care for trauma patients is discussed.