An educational programme in neonatal intensive care units (SEPREVEN): a stepped-wedge, cluster-randomised controlled trial.

BACKGROUND: Patients in neonatal intensive care units (NICUs) are at high risk of adverse events. The effects of medical and paramedical education programmes to reduce these have not yet been assessed. METHODS: In this multicentre, stepped-wedge, cluster-randomised controlled trial done in France, we randomly assigned 12 NICUs to three clusters of four units. Eligible neonates were inpatients in a participating unit for at least 2 days, with a postmenstrual age of 42 weeks or less on admission. Each cluster followed a 4-month multifaceted programme including education about root-cause analysis and care bundles. The primary outcome was the rate of adverse events per 1000 patient-days, measured with a retrospective trigger-tool based chart review masked to allocation of randomly selected files. Analyses used mixed-effects Poisson modelling that adjusted for time. This trial is registered with ClinicalTrials.gov, NCT02598609. FINDINGS: Between Nov 23, 2015, and Nov 2, 2017, event rates were analysed for 3454 patients of these 12 NICUs for 65 830 patient-days. The event rate per 1000 patient-days reduced significantly from the control to the intervention period (33·9 vs 22·6; incidence rate ratio 0·67; 95% CI 0·50-0·88; p=0·0048). INTERPRETATION: A multiprofessional safety-promoting programme in NICUs reduced the rate of adverse events and severe and preventable adverse events in highly vulnerable patients. This programme could significantly improve care offered to critically ill neonates. FUNDING: Solidarity and Health Ministry, France.

Biomechanical behaviour of lizard osteoderms and skin under external loading.

Many species of lizards are partially enveloped by a dermal armour made of ossified units called osteoderms. Lizard osteoderms demonstrate considerable species-specific variation in morphology and histology. Although a physical/protective role (against predators, prey, conspecifics and impact loading during falls) is frequently advanced, empirical data on the biomechanics of lizard osteoderms are scarce, limiting our understanding of form-function relationships. Here, we report deformation recorded at the surface of temporal osteoderms during controlled external loading of preserved specimens of 11 lizard species (Tiliqua rugosa, Tiliqua scincoides, Corucia zebrata, Pseudopus apodus, Timon lepidus, Matobosaurus validus, Broadleysaurus major, Tribolonotus gracilis, Tribolonotus novaeguineae, Heloderma horridum and Heloderma suspectum). Based on the strain recorded in situ and from isolated osteoderms, the skin of the species investigated can be ranked along a marked stiffness gradient that mostly reflects the features of the osteoderms. Some species such as T. rugosa and the two Heloderma species had very stiff osteoderms and skin while others such as T. lepidus and P. apodus were at the other end of the spectrum. Histological sections of the osteoderms suggest that fused (versus compound) osteoderms with a thick layer of capping tissue are found in species with a stiff skin. In most cases, loading neighbouring osteoderms induced a large strain in the instrumented osteoderm, attesting that, in most species, lizard osteoderms are tightly interconnected. These data empirically confirm that the morphological diversity observed in lizard osteoderms is matched by variability in biomechanical properties.

Unprecedented Biting Performance in Herbivorous Fish: How the Complex Biting System of Pomacentridae Circumvents Performance Trade-Offs.

AbstractIt is well accepted that the complexity of functional systems may mitigate performance trade-offs. However, data supporting this theory are hard to find because they need to be based on a functional system with different complexity levels in closely related species. The Pomacentridae (damselfishes) provide an excellent opportunity to test this hypothesis because most of the species have two mouth-closing systems: the first using the adductor mandibulae, as in all teleost fishes, and the second relying on the ceratomandibular (cmd) ligament, a synapomorphic trait of the family. Interestingly, some pomacentrids have secondarily lost the cmd ligament during evolution and therefore have a less complex mouth-closing system. Using dissection, kinematic analysis, and mathematical modeling, we demonstrated that the possession of two mouth-closing systems enabled grazing damselfishes to have a forceful and extremely fast bite. This combination challenges a major functional trade-off in fish jaw dynamics, as systems better suited for force transmission are usually less suited for speed transmission, and vice versa. The combination of grazing behavior, small and robust lower jaws (conferring high biting force), and an ultrafast bite is unusual within actinopterygians. These attributes and their associated performance seem to be required conditions to colonize the ecological niche of farming, that is, the maintenance of small filamentous algae crops serving as both food and storage.

The use of machine learning to detect foraging behaviour in whale sharks: a new tool in conservation.

In this study we present the first attempt at modelling the feeding behaviour of whale sharks using a machine learning analytical method. A total of eight sharks were monitored with tri-axial accelerometers and their foraging behaviours were visually observed. Our results highlight that the random forest model is a valid and robust approach to predict the feeding behaviour of the whale shark. In conclusion this novel approach exposes the practicality of this method to serve as a conservation tool and the capability it offers in monitoring potential disturbances of the species.

Seasonal trends in whale shark Rhincodon typus sightings in an established tourism site in the Gulf of California, Mexico.

The number of individual whale shark Rhincodon typus sightings registered October 2015-March 2018 in Bahia de La Paz, Mexico, ranged from 73 to 129 animals per season (total 1662), with the majority of them identified as males. Density plot maps showed high correlations in sightings between sample seasons and revealed potential hotspot areas. Our study provides an essential baseline of information for the management of whale shark conservation and the associated touristic activities in the region.

Trait decoupling promotes evolutionary diversification of the trophic and acoustic system of damselfishes.

Trait decoupling, wherein evolutionary release of constraints permits specialization of formerly integrated structures, represents a major conceptual framework for interpreting patterns of organismal diversity. However, few empirical tests of this hypothesis exist. A central prediction, that the tempo of morphological evolution and ecological diversification should increase following decoupling events, remains inadequately tested. In damselfishes (Pomacentridae), a ceratomandibular ligament links the hyoid bar and lower jaws, coupling two main morphofunctional units directly involved in both feeding and sound production. Here, we test the decoupling hypothesis by examining the evolutionary consequences of the loss of the ceratomandibular ligament in multiple damselfish lineages. As predicted, we find that rates of morphological evolution of trophic structures increased following the loss of the ligament. However, this increase in evolutionary rate is not associated with an increase in trophic breadth, but rather with morphofunctional specialization for the capture of zooplanktonic prey. Lineages lacking the ceratomandibular ligament also shows different acoustic signals (i.e. higher variation of pulse periods) from others, resulting in an increase of the acoustic diversity across the family. Our results support the idea that trait decoupling can increase morphological and behavioural diversity through increased specialization rather than the generation of novel ecotypes.

Reduced fish diversity despite increased fish biomass in a Gulf of California Marine Protected Area.

Multi-use marine protected areas (MUMPAs) are a commonly applied tool for marine conservation in developing countries, particularly where large no-take reserves are not socially or politically feasible. Although MUMPAs have produced benefits around the world, the persistence of moderate fishing pressure reduces the likelihood of achieving the primary objective of these areas, which is the conservation of ecosystems. In this study we used traditional and functional metrics to evaluate how fish assemblages changed through time in a MUMPA, including shifts in species responses and in ecological processes. We conducted visual censuses of fishes at Espíritu Santo Island, México (MUMPA; N = 320; 24°N, 110°W) from 2005 to 2017 to assess fish richness, size-distribution and density. Three functional indices were calculated using six traits (size, mobility, period of activity, aggregation, position in water column and diet): functional richness (volume occupied by species), dispersion (complementarity between species) and originality (inverse of functional redundancy). We compared fish diversity among three management zone types (sustainable fishing, traditional fishing and no-take zones), through a 13-year period, assessing which species increased or decreased in occurrence, density, and biomass, and how indices respond over time. Despite a general increase in biomass and stability in density and originality, we detected a reduction in fish biodiversity in the form of declines in species and functional richness, which could imply the risk of local extinction and decrease in certain ecosystem processes. In addition, changes in functional dispersion showed that some functions are losing representation through time. Although no single cause is apparent, such factors as competitive interactions, habitat loss and persistence of fishing pressure potentially explain these decreases. The rise in biomass was associated with a general increase in the average size, rather than increased biomass of commercial species, as the latter remained stable during the study period. Expansion of no-take areas, enforcement of fishing regulations, and surveillance in core zones, should be implemented to reverse the decline in particular species and to promote conservation of fish functional diversity in this MUMPA.

Pediatric Life-Threatening Coronavirus Disease 2019 With Myocarditis.

We report the case of a pediatric life-threatening coronavirus disease 2019 who presented as myocarditis with heart failure. Clinicians should be aware of this severe presentation of the disease in children, possibly linked to an exaggerated inflammatory host immune response to severe acute respiratory syndrome coronavirus 2.

Ecomorphology, trophic niche, and distribution divergences of two common damselfishes in the Gulf of California.

Damselfishes of the genus Stegastes are among the most conspicuous benthic reef-associated fish in the Gulf of California, and the two most commonly found species are the Beaubrummel Gregory Stegastes flavilatus and the Cortez damselfish Stegastes rectifraenum. Both species are described as ecologically and morphologically very similar. However, the niche theory predicts that coexisting species will tend to minimize competition through niche partitioning. We, therefore, investigated the degree of their ecological similarity through their morphology, trophic ecology, and spatial distribution, as well as, the effects of environmental variables on their abundance. We showed that S. rectifraenum is highly abundant in the entire Gulf of California while S. flavilatus is only found in the central and southern part. The abundance of S. rectifraenum was higher in shallow water and decreased when the cover of macroalgae and sand increased. No environmental variable was related to the abundance of S. flavilatus. Both species had distinct isotopic niches: S. flavilatus fed almost exclusively on plankton and zoobenthos, while S. rectifraenum had an omnivorous diet mixing turf, zoobenthos and plankton. The diet divergence was reflected in the morphology of the two species. Stegastes flavilatus had a more rounded body shape, with a higher supraoccipital crest and more gill rakers than S. rectifraenum, which may increase its ability to feed on vagile invertebrates and zooplankton. Our results support the hypothesis that a niche partition has occurred between the two species. Furthermore, the importance of planktonic food sources to both species, considered as benthic territorial feeders, challenges the traditional ecological description of the Stegastes species.

Distribution of F-18 fluorodeoxyglucose (F-18 FDG) in abdominal aortic aneurysm: high accumulation in macrophages seen on PET imaging and immunohistology.

A 68-year-old man was hospitalized for unstable angina and underwent emergency coronary artery bypass surgery. During the operation, a pulsatile large abdominal aortic aneurysm (AAA) was discovered. To define the optimal treatment of the abdominal aneurysm, after bypass surgery, CT scans and positron emission tomography (PET) were performed, as we routinely do. PET imaging combined with immunohistologic examination showed a region of increased F-18 FDG uptake corresponding to an inflammatory infiltrate in the aortic wall in contrast to the thrombus in the aneurysm (devoid of inflammatory cells). The luminal area showed midlevel F-18 FDG uptake corresponding to circulating mediators.

A morphological novelty for feeding and sound production in the yellowtail clownfish.

The yellowtail clownfish Amphiprion clarkii is able to close its mouth very quickly by means of the cerato-mandibular (c-md) ligament, a synapomorphic trait of Pomacentridae joining the hyoid bar to the medial part of the lower jaw. This fast closure induces tooth collision, thus producing sounds that the clownfish uses during agonistic behaviors. To investigate whether this rapid jaw movement is also used during feeding, we analyzed the kinematics of sound production and feeding. Sound production, feeding on live planktonic prey, and feeding on food attached to tweezers was filmed with a high-speed camera. Three kinds of kinematic patterns were detected and were associated with the two different types of food presented: one performed to catch planktonic prey (PP), and two (called B-1 and B-2) to bite attached food items. The kinematic pattern of B-2 is similar to that observed during sound production (SP) and the transection of the c-md ligament highlights that sound production and biting-2 motions are dependent on this morphological trait. Our data show that the c-md ligament in addition to its role in sound production allows duplication of the mouth-closing mechanism during feeding. This highlights the key role played by the c-md ligament in sound production and feeding on attached prey. J. Exp. Zool. 323A: 227-238, 2015. © 2015 Wiley Periodicals, Inc.

The impact of different antibiotic regimens on the emergence of antimicrobial-resistant bacteria.

BACKGROUND: The emergence and ongoing spread of antimicrobial-resistant bacteria is a major public health threat. Infections caused by antimicrobial-resistant bacteria are associated with substantially higher rates of morbidity and mortality compared to infections caused by antimicrobial-susceptible bacteria. The emergence and spread of these bacteria is complex and requires incorporating numerous interrelated factors which clinical studies cannot adequately address. METHODS/PRINCIPAL FINDINGS: A model is created which incorporates several key factors contributing to the emergence and spread of resistant bacteria including the effects of the immune system, acquisition of resistance genes and antimicrobial exposure. The model identifies key strategies which would limit the emergence of antimicrobial-resistant bacterial strains. Specifically, the simulations show that early initiation of antimicrobial therapy and combination therapy with two antibiotics prevents the emergence of resistant bacteria, whereas shorter courses of therapy and sequential administration of antibiotics promote the emergence of resistant strains. CONCLUSIONS/SIGNIFICANCE: The principal findings suggest that (i) shorter lengths of antibiotic therapy and early interruption of antibiotic therapy provide an advantage for the resistant strains, (ii) combination therapy with two antibiotics prevents the emergence of resistance strains in contrast to sequential antibiotic therapy, and (iii) early initiation of antibiotics is among the most important factors preventing the emergence of resistant strains. These findings provide new insights into strategies aimed at optimizing the administration of antimicrobials for the treatment of infections and the prevention of the emergence of antimicrobial resistance.

Modeling antibiotic resistance in hospitals: the impact of minimizing treatment duration.

Infections caused by antibiotic-resistant pathogens are a global public health problem. Numerous individual- and population-level factors contribute to the emergence and spread of these pathogens. An individual-based model (IBM), formulated as a system of stochastically determined events, was developed to describe the complexities of the transmission dynamics of antibiotic-resistant bacteria. To simplify the interpretation and application of the model's conclusions, a corresponding deterministic model was created, which describes the average behavior of the IBM over a large number of simulations. The integration of these two model systems provides a quantitative analysis of the emergence and spread of antibiotic-resistant bacteria, and demonstrates that early initiation of treatment and minimization of its duration mitigates antibiotic resistance epidemics in hospitals.