Islands Promote Diversification of the Silvereye Species Complex: A Phylogenomic Analysis of a Great Speciator

ABSTRACT Geographic isolation plays a pivotal role in speciation by restricting gene flow between populations through distance or physical barriers. However, the speciation process is complex, influenced by the interplay between dispersal ability and geographic isolation, as seen in “great speciators” – bird species that simultaneously have broad island distributions but high levels of subspecific diversity. Comparing genomic population differentiation in species that occupy both continental and island settings can reveal the effects of different forms of geographic isolation and validate if the primary mechanism proposed to catalyse a great speciator pattern, that is, dispersal reduction following island colonisation, has occurred. The highly diverse white‐eye family Zosteropidae includes several great speciators, including the silvereye ( Zosterops lateralis ), with 16 subspecies (11 occurring on islands), distributed on the Australian continent and numerous southwest Pacific islands. We compared continental and island patterns of divergence using whole genome and morphological data. Australian mainland populations showed a low genetic population structure, lack of isolation by distance patterns and low morphological diagnosability, suggesting that the species' dispersal propensity in a continental setting is sufficient to overcome multiple forms of geographic barriers and large geographic distances. In contrast, except for island populations less than 200 years old, most island populations were highly genomically structured with clearer morphological diagnosability even if separated by relatively short geographic distances. The inferred reduction of dispersal propensity in island situations is consistent with the proposed model of great speciator formation on islands. Our phylogenomic analyses also allowed resolution of the silvereyes' evolutionary position, showing their relatively early emergence (~1.5 Mya) within the rapidly radiating Zosteropidae, while population‐level analyses demonstrated where morphological subspecies and genomic data align and disagree. However, the silvereye example also shows how uncertainties about relationships remain when reconstructing evolutionary history in rapidly radiating groups, even when whole genome data is available. Altogether, our results show how within‐species genomic and morphological patterns measured over broad spatial scales and with varying geographic contexts can help reveal when particular stages of speciation such as great speciators are likely to emerge.

That's So Last Season: Unraveling the Genomic Consequences of Fur Farming in Arctic Foxes ( Vulpes lagopus )

ABSTRACT Humans have relied on animal fur for centuries, yet fur farming only began recently during the mid‐19th Century. Little is known about this incipient domestication or the genomic processes involved. Domestication may involve founder effects, population bottlenecks and low population size, which, when combined with intense artificial selection, lead to inbreeding, a limited gene pool and reduced fitness. The arctic fox ( Vulpes lagopus ) has been farmed intensively since the early 1900s and has been artificially selected for economic phenotypes. We investigated the origin of these lineages and the genomic consequences of intensive farming by comparing the genomes of farmed and wild arctic foxes from across their range. Our research indicates recent inbreeding through long Runs of Homozygosity and reduced genomic variation in farmed foxes relative to their respective wild populations. We identified a coastal ecotype origin for all Fennoscandian farmed arctic foxes, aligning them phylogenetically with the wild Icelandic population, a geographically isolated and phenotypically distinct coastal lineage. The depleted genome‐wide heterozygosity and increased recent inbreeding in farmed fox lineages is consistent with a heavy consequence of domestication, shedding light on the demographic history and genomic consequences of human manipulation. We highlight the need for increased genomic investigations into fur farm populations to understand the incipient domestication process and uncover the cost of intense farming. The genomic consequences of domestication must be considered in the management of fur farms, with actionable steps needed to prevent descendants of escaped farmed foxes from polluting the gene pool in the wild through introgression.

Clinical practice guideline repository: Development of a learning tool for residents

Comparative Clinical and Imaging‐Based Evaluation of Therapeutic Modalities in CNS Embryonal Tumours With PLAGL Amplification

ABSTRACT Aims Embryonal tumours with PLAGL1 or PLAGL2 amplification (ET, PLAGL) show substantial heterogeneity regarding their clinical characteristics and have been treated inconsistently, resulting in diverse outcomes. In this study, we aimed to evaluate the clinical behaviour of ET, PLAGL and elucidate their response pattern across the different applied treatment regimens. Methods We conducted an in‐depth retrospective analysis of clinical and serial imaging data of 18 patients with ET, PLAGL (nine each of PLAGL1 and PLAGL2 amplified). Results Patients with PLAGL1 ‐amplified tumours (ET, PLAGL1) had fewer relapses (3/9), while PLAGL2 ‐amplified tumours (ET, PLAGL2) were prone to early relapse or progression (8/9) and to distant, leptomeningeal and intraventricular relapses. Progression‐free survival differed significantly between the subtypes (log‐rank test, p  = 0.0055). Postoperative treatment included chemotherapy ( n  = 17, various protocols), alone ( n  = 8) or combined with radiotherapy ( n  = 9). Responses to chemotherapy were observed in both subtypes, and incomplete resection was not associated with inferior survival. All three survivors with ET, PLAGL2 were treated with induction and high‐dose chemotherapy with ( n  = 1—low‐dose CSI and boost) or without ( n  = 2) radiotherapy, whereas five patients with less intensive chemotherapy relapsed. All six survivors with ET, PLAGL1 were treated with conventional chemotherapy regimens, with ( n  = 4—local radiotherapy n  = 3; CSI and boost n  = 1) or without ( n  = 2) radiotherapy. Two patients with ET, PLAGL1 relapsed after 8 years. Conclusions Adjuvant therapy should be considered for all ET, PLAGL patients: Patients with ET, PLAGL2 might benefit from intensified chemotherapy regimens. In contrast, patients with ET, PLAGL1 showed superior outcomes without high‐dose chemotherapy or craniospinal irradiation.

A Bundle of Interventions to Prevent Pressure Ulcers During Prone Position in Adult Patients With Acute Respiratory Distress Syndrome: Results of a French Stepped‐Wedge Randomized Controlled Trial

ABSTRACT Background In patients with moderate‐to‐severe acute respiratory distress syndrome, the frequency of pressure ulcers is higher in the prone position than in the supine position. Aim To assess the effect of a bundle of interventions to prevent pressure ulcers in patients with acute respiratory distress syndrome prone. Study Design ESCARD is a stepped‐wedge prospective multicentre trial conducted in France that included patients with moderate‐to‐severe acute respiratory distress syndrome, intubated and with an indication for pronation. In the control period, patients received the routine means of each centre. In the experimental period, the bundle of specific standardized means included: eye protection with methylcellulose; strapped lower eyelids; 15° body inclination; specific cushions inserted between the mattress and head/thorax and knees/feet; head rotation every 4 h. The primary end‐point was the occurrence of a new pressure ulcer at any location and stage in the anterior part of the body 7 days after inclusion. It was assessed from pictures taken in the supine position and independently analysed by two experts blinded to the allocated period. Results From 16 April 2018 to 3 December 2020 (with an interruption between 12 March and 15 July 2020 because of COVID pandemic), a total of 160 patients were included in 9 centres; 156 were analysed. At the first proning session, all 6 specific preventive means were implemented in 1.2% of the patients in the control period and 91.8% in the experimental period. At Day 7, 53 patients (63.9%) in the control versus 40 (54.8%) in the experimental period had a new pressure ulcer at any location and of any stage (odds ratio = 0.92; 95% confidence interval [0.39; 2.18]). There was a 42.8% discrepancy between the two experts. Conclusions In this prospective multicentre stepped‐wedge trial, the bundle of interventions did not lead to a significant reduction in the frequency of new pressure ulcers in moderate‐to‐severe acute respiratory distress syndrome patients treated by prone position. Relevance to Clinical Practice The critical care nurses were able to manage patients enrolled in a complex trial up to its planned end. Even though negative, the study should encourage intensive care unit (ICU) nurses to better define the bundle of interventions including introducing other methods not used in the present study. ICU nurses should also assess the stage of pressure ulcers consistently over time. ICU nurses should consider further studies because pressure ulcer is a relevant issue of concern during the pronation in acute respiratory distress syndrome patients. If so, the new trial should include a larger number of ICUs. Trial Registration: The protocol was approved by an ethics committee (number 2017‐A01449‐44 on 7 October 2017) and was recorded in clinicaltrials.gov (NCT03125421)

Floral phenotypic divergence and genomic insights in an Ophrys orchid: unraveling early speciation processes

Summary Adaptive radiation in Ophrys orchids leads to complex floral phenotypes that vary in scent, color and shape. Using a novel pipeline to quantify these phenotypes, we investigated trait divergence at early stages of speciation in six populations of Ophrys aveyronensis experiencing recent allopatry. By integrating different genetic/genomic techniques, we investigated: variation and integration of floral components (scent, color and shape); phenotypes and genomic regions under divergent selection; and the genomic bases of trait variation. We identified a large genomic island of divergence, likely associated with phenotypic variation in particular in floral odor. We detected potential divergent selection on macular color, while stabilizing selection was suspected on floral morphology and for several volatile olfactive compounds. We also identified candidate genes involved in anthocyanin and in steroid biosynthesis pathways associated with standing genetic variation in color and odor. This study sheds light on early differentiation in Ophrys , revealing patterns that often become invisible over time, that is the geographic mosaic of traits under selection and the early appearance of strong genomic divergence. It also supports a crucial genomic region for future investigation and highlights the value of a multifaceted approach in unraveling speciation within taxa with large genomes.

Alleviation of water‐deficit inhibition of plant growth by rhizosphere microbiota conditioning

Summary Rhizosphere microbiota conditioning is a promising strategy to enhance plant growth. We conditioned the rhizosphere microbiota of Brassica juncea to water deficit to assess its impact on plant growth. In a glasshouse, plants were first grown under well‐watered conditions, then exposed to moderate (MD, pF = 2.3) or extreme (ED, pF = 3.5) water deficits. We extracted and inoculated the rhizosphere microbiota to new plants and repeated this process 10 times. Control plants were kept well‐watered. We monitored changes in plant phenotypes and in rhizosphere microbial communities (bacteria and eukaryotes). The initial water‐deficit growth inhibition of plants was successfully alleviated by 19.3% in MD and 29.4% in ED after conditioning (MD: from −35.6% to −16.3%; ED: from −56.8% to −27.4%). This beneficial effect on plants was not observed during the well‐watered phases, suggesting an active role of the microbiota when water became scarce. The increase in plant growth correlated with aggregated rhizosphere soil and significantly matched changes in the bacterial community, featuring reduced diversity and increased biofilm production capacity along the conditioning process. We showed that microbiota conditioning was a fast and efficient way to achieve better plant growth under adverse conditions, likely via the adaptation capabilities of the rhizosphere bacterial community.

Fluctuations in angle lambda with the pupil diameter and correlations with biometric values in a healthy population

Abstract Purpose Angle lambda ( λ ) is defined as the angle between the line of sight and the pupillary axis at the entrance pupil. We previously developed a child‐friendly and portable method to measure this angle in daily practice. In a given population, angle λ fluctuates according to age or refractive error. As changes in the pupil diameter induce changes in the location of the pupil centre, it was hypothesised that a given subject will exhibit several angles λ , varying with the luminance level. The study aimed to investigate correlations between angle λ and biometric values and to analyse the effects of pupil dilation and entrance pupil location on angle λ . Method The study was performed on 70 right eyes from 70 participants (58 women, 12 men; mean age 22.91 ± 2.57 years). Angle λ was assessed under photopic and scotopic luminance conditions. Angle λ was also measured under standard luminance conditions in a subgroup of 15 eyes. Axial length, anterior chamber depth, chord μ (coaxial corneal light reflex position) and the optic disc to fovea distance (OFD) were also measured. The pupil centre offset was quantified by digital analysis. Results Mean photopic and scotopic angle λ values were +2.81 ± 2.34° and +3.30 ± 2.59°, respectively. A negative correlation was found between axial length, anterior chamber depth or OFD and both photopic and scotopic angle λ . A positive correlation was found between spherical equivalent or chord μ and angle λ . The mean pupil offset was significantly higher under photopic than scotopic conditions and was negatively correlated with angle λ for both luminance levels. Conclusion This study confirms that angle λ is correlated with biometric values. Furthermore, fluctuation of pupil diameter induces variations in angle λ . Thus, a given subject exhibits several angles λ according to the luminance level.

Egg allergen‐specific T‐cell and cytokine responses in healthy and egg‐allergic children naturally tolerating baked egg

Abstract Background Type 1 regulatory T (Tr1) cells are critical players in maintaining peripheral tolerance, by producing high IL‐10 levels in association with inducible T‐cell co‐stimulator (ICOS) expression. Whether these cells play a role in naturally acquired baked egg tolerance is unknown. Objectives Evaluate frequencies of egg‐responsive Tr1 and Th2 cells in egg‐allergic children that naturally acquired baked egg tolerance (BET) versus non‐egg‐allergic (NEA) children. Methods Peripheral blood mononuclear cells from 70 natural BET and 15 NEA children were stimulated for 7 days with ovalbumin and ovomucoid. By flowcytometry, egg‐responsive Tr1 cells were identified by co‐expression of CD49b and LAG3, and Th2 cells by expression of CD49b but absence of LAG3. Seven‐day cultured supernatant was analyzed for Th1, Th2, Tr1, and Th17 cytokines by MSD. Results Natural BET children had a higher percentage of egg‐responsive Th2 cells vs. NEA children (6.75% vs. 10.35%, p  = .006). No significant difference was found in frequencies of egg‐responsive Tr1 cells between NEA and natural BET children (11.40% vs. 12.55%, p  = .42), although Tr1‐related IL‐10 and IL‐21 production was higher in BET children. Interestingly, egg‐responsive Tr1 cells from NEA children expressed higher ICOS levels vs. natural BET children (97.90 vs. 88.20, p  < .0001). Supernatant from natural BET children showed elevated levels of Th2 cytokines IL‐5, IL‐9 and IL‐13 and Th17 cytokine IL‐17A. Conclusion Natural BET children maintain increased egg‐specific Th2 responses, along with comparable proportions of egg‐responsive Tr1 cells exhibiting higher IL‐10 but lower ICOS expression in comparison with NEA children.

Histiocytoid Sweet Syndrome With Paradoxical Neutropenia in a Pediatric Patient

ABSTRACT Histiocytoid Sweet syndrome (HSS) is a rare inflammatory skin condition characterized by the infiltration of mononuclear cells in the dermis and leukocytosis with neutrophilia. This uncommon variant of classic Sweet syndrome is rarely reported in the literature, especially in pediatric patients. We present a case of an 8‐month‐old boy who developed idiopathic HSS along with autoimmune neutropenia. This report adds to the understanding and management of HSS with neutropenia in pediatric patients.