Protein import into bacterial endosymbionts and evolving organelles.

Bacterial endosymbionts are common throughout the eukaryotic tree of life and provide a range of essential functions. The intricate integration of bacterial endosymbionts into a host led to the formation of the energy-converting organelles, mitochondria and plastids, that have shaped eukaryotic evolution. Protein import from the host has been regarded as one of the distinguishing features of organelles as compared to endosymbionts.

A novel kleptoplastidic symbiosis revealed in the marine centrohelid Meringosphaera with evidence of genetic integration.

Plastid symbioses between heterotrophic hosts and algae are widespread and abundant in surface oceans. They are critically important both for extant ecological systems and for understanding the evolution of plastids. Kleptoplastidy, where the plastids of prey are temporarily retained and continuously re-acquired, provides opportunities to study the transitional states of plastid establishment.

Rapid compensatory evolution can rescue low fitness symbioses following partner switching.

Partner switching plays an important role in the evolution of symbiosis, enabling local adaptation and recovery from the breakdown of symbiosis. Because of intergenomic epistasis, partner-switched symbioses may possess novel combinations of phenotypes but may also exhibit low fitness due to their lack of recent coevolutionary history. Here, we examine the structure and mechanisms of intergenomic epistasis in the Paramecium-Chlorella symbiosis and test whether compensatory evolution can rescue initially low fitness partner-switched symbioses.

Comparison of Independent Evolutionary Origins Reveals Both Convergence and Divergence in the Metabolic Mechanisms of Symbiosis.

Through the merger of previously independent lineages, symbiosis promotes the acquisition of new traits and exploitation of inaccessible ecological niches [1, 2], driving evolutionary innovation and important ecosystem functions [3-6]. The transient nature of establishment makes study of symbiotic origins difficult, but experimental comparison of independent origins could reveal the degree of convergence in the underpinning mechanisms [7, 8]. We compared the metabolic mechanisms of two independent origins of Paramecium bursaria-Chlorella photosymbiosis [9-11] using a reciprocal metabolomic pulse-chase method.

The role of exploitation in the establishment of mutualistic microbial symbioses.

Evolutionary theory suggests that the conditions required for the establishment of mutualistic symbioses through mutualism alone are highly restrictive, often requiring the evolution of complex stabilising mechanisms. Exploitation, whereby initially the host benefits at the expense of its symbiotic partner and mutual benefits evolve subsequently through trade-offs, offers an arguably simpler route to the establishment of mutualistic symbiosis. In this review, we discuss the theoretical and experimental evidence supporting a role for host exploitation in the establishment and evolution of mutualistic microbial symbioses, including data from both extant and experimentally evolved symbioses.

Operational Impact of a Critical Care Transport Duty Time Tool Implementation: A Quality Improvement Project to Enhance Crew and Patient Safety.

Objective: The Commission on Accreditation of Medical Transport Systems requires transport programs to have operational risk assessment tools that must address issues such as transport acceptance with tools for assessing pilot/driver and crew alertness and fatigue, aviation decision making, and mission acceptance/medical decision making. The objective of this study was to evaluate the impact the implementation of this tool has on programmatic operations.

Methods: This hospital-based dedicated pediatric/neonatal transport team has experienced rapid increase in volume as well as an expanding response area.

Variation and asymmetry in host-symbiont dependence in a microbial symbiosis.

Background: Symbiosis is a major source of evolutionary innovation and, by allowing species to exploit new ecological niches, underpins the functioning of ecosystems. The transition from free-living to obligate symbiosis requires the alignment of the partners' fitness interests and the evolution of mutual dependence. While symbiotic taxa are known to vary widely in the extent of host-symbiont dependence, rather less is known about variation within symbiotic associations.

The Effect of Team Configuration on the Incidence of Adverse Events in Pediatric Critical Care Transport.

Objective: Specialty pediatric transport teams are widely used for pediatric interfacility transport in the United States, with little industry consensus on optimal team configuration. The aim of this study is to assess the quality of the nurse/paramedic specialty team configuration as indirectly measured by the rate of adverse events in these transports.

Methods: Retrospective analysis of pediatric transport data from a hospital-based dedicated pediatric/neonatal transport team was conducted for patients transported in 2016.

Metabolic constraints for a novel symbiosis.

Ancient evolutionary events are difficult to study because their current products are derived forms altered by millions of years of adaptation. The primary endosymbiotic event formed the first photosynthetic eukaryote resulting in both plants and algae, with vast consequences for life on Earth. The evolutionary time that passed since this event means the dominant mechanisms and changes that were required are obscured.

Host control and nutrient trading in a photosynthetic symbiosis.

Photosymbiosis is one of the most important evolutionary trajectories, resulting in the chloroplast and the subsequent development of all complex photosynthetic organisms. The ciliate Paramecium bursaria and the alga Chlorella have a well established and well studied light dependent endosymbiotic relationship. Despite its prominence, there remain many unanswered questions regarding the exact mechanisms of the photosymbiosis.

Two hospitals with 1 trauma system: a joint approach to the care of the injured patient.

Background: Trauma centers are closing at an alarming rate, but the need for trauma care persists. This article shows the sustainability and feasibility of a joint trauma system whereby 2 university-affiliated hospitals function as a single trauma center system in a moderate-sized city.

Methods: Since 1994, 3 days per week, trauma patients are transported by emergency medical services (EMS) to hospital A.

FAST scan: is it worth doing in hemodynamically stable blunt trauma patients?

Background: During the last decade, focused assessment with sonography for trauma increasingly has become the initial diagnostic modality of choice in trauma patients. It is still questionable, however, whether its use results in the underdiagnosis of intra-abdominal injury. It also remains doubtful whether a positive focused assessment with sonography for trauma affects clinical decision making in hemodynamically stable blunt trauma patients as evidenced through abdominal computerized tomography use.