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Most speciation events probably occur gradually, without complete and immediate reproductive isolation, but the full extent of gene flow between diverging species has rarely been characterized on a genome-wide scale. Documenting the extent and timing of admixture between diverging species can clarify the role of geographic isolation in speciation. Here we use new methodology to quantify admixture at different stages of divergence in Heliconius butterflies, based on wholegenome sequences of 31 individuals. Comparisons between sympatric and allopatric populations of H. melpomene, H. cydno, and H. timareta revealed a genome-wide trend of increased shared variation in sympatry, indicative of pervasive interspecific gene flow. Up to 40% of 100-kb genomic windows clustered by geography rather than by species, demonstrating that a very substantial fraction of the genome has been shared between sympatric species. Analyses of genetic variation shared over different time intervals suggested that admixture between these species has continued since early in speciation. Alleles shared between species during recent time intervals displayed higher levels of linkage disequilibrium than those shared over longer time intervals, suggesting that this admixture took place at multiple points during divergence and is probably ongoing. The signal of admixture was significantly reduced around loci controlling divergent wing patterns, as well as throughout the Z chromosome, consistent with strong selection for Mu¨llerian mimicry and with known Z linked hybrid incompatibility. Overall these results show that species divergence can occur in the face of persistent and genome-wide admixture over long periods of time., Organismic and Evolutionary Biology

Abstract Background Heliconius butterflies are an excellent system for studies of adaptive convergent and divergent phenotypic traits. Wing colour patterns are used as signals to both predators and potential mates and are inherited in a Mendelian manner. The underlying genetic mechanisms of pattern formation have been studied for many years and shed light on broad issues, such as the repeatability of evolution. In Heliconius melpomene, the yellow hindwing bar is controlled by the HmYb locus. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression that have key roles in many biological processes, including development. miRNAs could act as regulators of genes involved in wing development, patterning and pigmentation. For this reason we characterised miRNAs in developing butterfly wings and examined differences in their expression between colour pattern races. Results We sequenced small RNA libraries from two colour pattern races and detected 142 Heliconius miRNAs with homology to others found in miRBase. Several highly abundant miRNAs were differentially represented in the libraries between colour pattern races. These candidates were tested further using Northern blots, showing that differences in expression were primarily due to developmental stage rather than colour pattern. Assembly of sequenced reads to the HmYb region identified hme-miR-193 and hme-miR-2788; located 2380 bp apart in an intergenic region. These two miRNAs are expressed in wings and show an upregulation between 24 and 72 hours post-pupation, indicating a potential role in butterfly wing development. A search for miRNAs in all available H. melpomene BAC sequences (~ 2.5 Mb) did not reveal any other miRNAs and no novel miRNAs were predicted. Conclusions Here we describe the first butterfly miRNAs and characterise their expression in developing wings. Some show differences in expression across developing pupal stages and may have important functions in butterfly wing development. Two miRNAs were located in the HmYb region and were expressed in developing pupal wings. Future work will examine the expression of these miRNAs in different colour pattern races and identify miRNA targets among wing patterning genes.

Key Clinical Message: Elective amputation as a treatment for Body Integrity Identity Disorder (BIID) or Body Integrity Dysphoria (BID) where noninvasive treatments prove ineffective and the patient's distress is substantial, may permit long-term remission of symptoms at follow-up., Abstract: We present the one-year follow-up post-surgery of an ambidextrous male who sought elective amputation of his left hand's fourth and fifth fingers after an unsuccessful trial of psychotherapy and pharmacotherapy for Body Integrity Dysphoria. He had no psychiatric comorbidities. At one-year follow-up, his dysphoria was still in remission. He exhibited full adaptation in his social and occupational life, demonstrating increased ease in hand use compared to pre-amputation. He reported sleeping well, happiness, good health and continued acceptance by friends and family. This one-year post-surgery follow-up, at 22 years old, underscores the efficacy of amputation as a curative treatment, high patient satisfaction, and the quality of life gained through the procedure., Competing Interests: Dre Nadia Nadeau reports no financial relationship with commercial interests., (© 2024 The Author(s). Clinical Case Reports published by John Wiley & Sons Ltd.)

Competing Interests: CONFLICT OF INTEREST: No potential conflict of interest relevant to this article was reported.

Competing Interests: Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request.

Childhood acute lymphoblastic leukemia (cALL) survivors are at increased risk for bone comorbidities, but accurate screening tools for such comorbidities are limited. Polygenic scores (PGS) could stratify cALL survivors for risk of long-term adverse bone outcomes. We evaluated 214 (51% female) cALL survivors from the Prévenir les Effets TArdifs de la LEucémie study (median age 21 yr). Bone mineral density (BMD) measurements were obtained using dual X-ray absorptiometry at the lumbar spine (LS-BMD), femoral neck (FN-BMD), and total body (TB-BMD), and vertebral fractures (VF) were documented using the vertebral deformity criterion. We computed a PGS for adult heel quantitative ultrasound speed of sound (gSOS), known to be associated with the risk of osteoporotic fracture, using imputed genotype data of the participants, and tested it for association with BMD Z-scores and VF risk, adjusting for clinical risk factors, and in sex and prognostic risk-stratified analyses. We found that a gSOS below the mean was associated with lower BMD in all three sites in univariate and multivariate models. In univariate analyses, 1 SD increase in gSOS conferred a 0.16 SD increase in LS-BMD (95% CI 0.005-0.31), whereas a gSOS above the mean was associated with a 0.31 SD higher LS-BMD (95% CI 0.008-0.61), a 0.36 SD higher TB-BMD (95% CI 0.06-0.67), and a 0.43 SD higher FN-BMD (95% CI 0.13-0.72). Models combining gSOS with clinical risk factors explained up to 16% of the variance of BMD phenotypes and obtained an area under the receiver operating characteristic curve for VF of 0.77 in subgroup analyses. Cranial radiation, high cumulative glucocorticoid doses, high risk group, and male sex were significant risk factors for lower BMD Z-scores. In conclusion, a PGS, in combination with clinical risk factors, could be used as a tool to risk stratify cALL survivors for treatment-related bone morbidity., (© The Author(s) 2024. Published by Oxford University Press on behalf of the American Society for Bone and Mineral Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Competing Interests: The authors have no conflicts of interest or employment to disclose.

Introduction: The purpose of this study was to quantify the effects of the coronavirus disease 2019 (COVID-19) pandemic on pediatric emergency departments (PED) across the United States (US), specifically its impact on trainee clinical education as well as patient volume, admission rates, and staffing models., Methods: We conducted a cross-sectional study of US PEDs, targeting PED clinical leaders via a web-based questionnaire. The survey was sent via three national pediatric emergency medicine distribution lists, with several follow-up reminders., Results: There were 46 questionnaires included, completed by PED directors from 25 states. Forty-two sites provided PED volume and admission data for the early pandemic (March-July 2020) and a pre-pandemic comparison period (March-July 2019). Mean PED volume decreased >32% for each studied month, with a maximum mean reduction of 63.6% (April 2020). Mean percentage of pediatric admissions over baseline also peaked in April 2020 at 38.5% and remained 16.4% above baseline by July 2020. During the study period, 33 (71.1%) sites had decreased clinician staffing at some point. Only three sites (6.7%) reported decreased faculty protected time. All PEDs reported staffing changes, including decreased mid-level use, increased on-call staff, movement of staff between the PED and other units, and added tele-visit shifts. Twenty-six sites (56.5%) raised their patient age cutoff; median was 25 years (interquartile ratio 25-28). Of 44 sites hosting medical trainees, 37 (84.1%) reported a decrease in number of trainees or elimination altogether. Thirty (68.2%) sites had restrictions on patient care provision by trainees: 28 (63.6%) affected medical students, 12 (27.3%) affected residents, and two (4.5%) impacted fellows. Fifteen sites (34.1%) had restrictions on procedures performed by medical students (29.5%), residents (20.5%), or fellows (4.5%)., Conclusion: This study highlights the marked impact of the COVID-19 pandemic on US PEDs, noting decreased patient volumes, increased admission rates, and alterations in staffing models. During the early pandemic, educational restrictions for trainees in the PED setting disproportionately affected medical students over residents, with fellows' experience largely preserved. Our findings quantify the magnitude of these impacts on trainee pediatric clinical exposure during this period.

Objectives: (1) To measure sound exposures of marching band and non-marching band students during a football game, (2) to compare these to sound level dose limits set by NIOSH, and (3) to assess the perceptions of marching band students about their hearing health risk from loud sound exposure and their use of hearing protection devices (HPDs)., Methods: Personal noise dosimetry was completed on six marching band members and the band director during rehearsals and performances. Dosimetry measurements for two audience members were collected during the performances. Noise dose values were calculated using NIOSH criteria. One hundred twenty-three marching band members responded to a questionnaire analyzing perceptions of loud music exposure, the associated hearing health risks, and preventive behavior., Results: Noise dose values exceeded the NIOSH recommended limits among all six marching band members during rehearsals and performances. Higher sound levels were recorded during performances compared to rehearsals. The audience members were not exposed to hazardous levels. Most marching band members reported low concern for health effects from high sound exposure and minimal use of HPDs., Conclusion: High sound exposure and low concern regarding hearing health among marching band members reflect the need for comprehensive hearing conservation programs for this population.

Background: Many institutions track early ICU transfers (transfer from an inpatient floor to an ICU within 24 hours of admission) as a marker of quality of emergency department (ED) care. There are limited data evaluating whether patient characteristics or clinical outcomes differ on the basis of timing of ICU transfer within this 24-hour window., Methods: We conducted a retrospective cohort study examining all patients ≤21 years old admitted to an inpatient pediatric floor from the ED and subsequently transferred to an ICU within 24 hours of hospitalization. Patient characteristics and clinical outcomes were compared on the basis of timing (0-6 hours, 6-12 hours, 12-24 hours) of ICU transfer. Outcomes assessed included receipt of critical intervention, timing of intervention with respect to transfer, type of intervention received, hospital and ICU length of stay, and mortality at 72 hours and during hospitalization., Results: A total of 841 patients were transferred to an ICU within 24 hours from admission to a pediatric ward from the ED; 266 patients (32%) transferred within 6 hours of admission, 269 patients (32%) transferred between 6 and 12 hours, and 306 patients (36%) transferred between 12 and 24 hours. Patient characteristics did not materially differ on the basis of timing of ICU transfer, nor did clinical outcomes., Conclusions: Among children transferred to an ICU within 24 hours of hospitalization, patient characteristics and clinical outcomes did not materially differ based on the timing of transfer relative to admission from the ED., Competing Interests: POTENTIAL CONFLICTS OF INTEREST: The authors have no conflicts of interest relevant to this article to disclose., (Copyright © 2021 by the American Academy of Pediatrics.)

Background: Clinicians use the Modified Centor Score (MCS) to estimate the risk of group A streptococcal (GAS) pharyngitis in children with sore throat. The Infectious Diseases Society of America (IDSA) recommends neither testing nor treating patients with specific viral symptoms. The goal of this study is to measure the impact of those symptoms on the yield of GAS testing predicted by the MCS., Methods: Retrospective cohort study of all patients aged 3-21 years presenting with sore throat and tested for GAS in a pediatric emergency department (ED) in 2016. After identifying all patients tested for GAS, we used natural language processing (NLP) to identify the subgroup complaining of sore throat. We abstracted all MCS variables as well as symptoms suggestive of a viral etiology per the IDSA guideline (conjunctivitis, coryza, cough, diarrhea, hoarseness, ulcerative oral lesions, viral exanthema). We calculated the proportion of patients who tested positive for GAS by MCS with and without viral symptoms., Results: Of the 1574 patients included, 372 patients (24%) tested GAS positive. Patients with at least one viral symptom had a reduced GAS risk compared to those without any of the viral symptoms 91/547 (17% GAS positive) vs. 281/1027 (27%), odds ratio 0.53 (95% CI 0.41-0.69)., Conclusions: The presence of viral symptoms specified by the IDSA alters the predicted yield of testing by traditional MCS. Clinicians may consider adjusting interpretation of a patient's MCS based on the presence of viral symptoms, but viral symptoms may not always fully obviate the need for GAS testing., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The persistence of distinct warning signals within and between sympatric mimetic communities is a puzzling evolutionary question because selection favours convergence of colour patterns among toxic species. Such convergence is partly shaped by predators' reaction to similar but not identical stimulus (i.e. generalization behaviour), and generalization by predators is likely to be shaped by the diversity of local prey. However, studying generalization behaviour is generally limited to simple variations of prey colour patterns. Here, we used a computer game played by humans as surrogate predators to investigate generalization behaviours in simple (4 morphs) and complex (10 morphs) communities of unprofitable (associated with a penalty) and profitable butterflies. Colour patterns used in the game are observed in the natural populations of unprofitable butterfly species such as Heliconius numata . Analyses of 449 game participants' behaviours show that players avoided unprofitable prey more readily in simple than in complex communities. However, generalization was observed only in players that faced complex communities, enhancing the protection of profitable prey that looked similar to at least one unprofitable morph. Additionally, similarity among unprofitable prey also reduced attack rates only in complex communities. These results are consistent with previous studies using avian predators but artificial colour patterns and suggest that mimicry is more likely to evolve in complex communities where increases in similarity are more likely to be advantageous.

We demonstrate a methodology for replicating and projecting the path of COVID-19 using a simple epidemiology model. We fit the model to daily data on the number of infected cases in China, Italy, the United States, and Brazil. These four countries can be viewed as representing different stages, from later to earlier, of a COVID-19 epidemic cycle. We solve for a model-implied effective reproduction number R t each day so that the model closely replicates the daily number of currently infected cases in each country. For out-of-sample projections, we fit a behavioral function to the in-sample data that allows for the endogenous response of R t to movements in the lagged number of infected cases. We show that declines in measures of population mobility tend to precede declines in the model-implied reproduction numbers for each country. This pattern suggests that mandatory and voluntary stay-at-home behavior and social distancing during the early stages of the epidemic worked to reduce the effective reproduction number and mitigate the spread of COVID-19., (© 2020 The Authors.)

Background: There is a paucity of data describing pediatric patients transferred to an ICU within 24 hours of hospital admission from the emergency department (ED)., Methods: We conducted a retrospective cohort study of patients ≤21 years old transferred from an inpatient floor to an ICU within 24 hours of ED disposition from 2007 to 2016 in a tertiary children's hospital. Patients transferred to an ICU after planned operative procedures were excluded. Rate of transfer, clinical course, and baseline demographic and/or clinical characteristics of these patients are described., Results: The study cohort consisted of 841 children, representing 1% of 82 397 non-ICU ED admissions over the 10-year period. Median age was 5.1 years, 43% had ≥1 complex chronic condition, and 47% were hospitalized within the previous year (27% in the ICU). The majority of transfers were for respiratory conditions (65%) and cardiovascular compromise (18%). Median time from hospitalization to ICU transfer was 9.1 hours (interquartile range 5.1-14.9 hours). Thirty-eight percent of transfers received 1 or more critical interventions within 72 hours of hospitalization, most commonly positive pressure ventilation (29%) and vasoactive infusion (9%). Median time to intervention from hospitalization was 13.6 hours (interquartile range 7.5-21.6 hours), 0.8% of children died within 72 hours of hospitalization, and 2.4% died overall., Conclusions: In this single pediatric academic center, 1% of hospitalized children were transferred to an ICU within 24 hours of ED disposition. One-third of patients received a critical intervention, and 2.4% died. Although most ED dispositions are appropriate, future efforts to identify patients at the highest risk of deterioration are warranted., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2019 by the American Academy of Pediatrics.)

The prevalence of obesity has risen rapidly in the United States in the past 20 years. Up to 25% of US children are obese, and obesity can be directly correlated with immediate and long-term health consequences. Pediatric obesity can harm multiple body systems and is a public health issue. This article focuses on how obesity affects a child's respiratory system, including pulmonary function, exercise intolerance, gas exchange, and airway musculature.

Bacterial type 2 secretion systems (T2SS), type 4 pili, and archaeal flagella assemble fibres from initially membrane-embedded pseudopilin and pilin subunits. Fibre subunits are made as precursors with positively charged N-terminal anchors, whose cleavage via the prepilin peptidase, essential for pilin membrane extraction and assembly, is followed by N-methylation of the mature (pseudo)pilin N terminus. The conserved Glu residue at position 5 (E5) of mature (pseudo)pilins is essential for assembly. Unlike T4 pilins, where E5 residue substitutions also abolish N-methylation, the E5A variant of T2SS pseudopilin PulG remains N-methylated but is affected in interaction with the T2SS component PulM. Here, biochemical and functional analyses showed that the PulM interaction defect only partly accounts for the PulG E5A assembly defect. First, PulG T2A variant, equally defective in PulM interaction, remained partially functional. Furthermore, pseudopilus assembly defect of pulG(E5A) mutant was stronger than that of the pulM deletion mutant. To understand the dominant effect of E5A mutation, we used molecular dynamics simulations of PulG E5A , methylated PulG WT (MePulG WT ), and MePulG E5A variant in a model membrane. These simulations pointed to a key role for an intramolecular interaction between the pseudopilin N-terminal amine and E5 to limit polar interactions with membrane phospholipids. N-methylation of the N-terminal amine further limited its interactions with phospholipid head-groups to facilitate pseudopilin membrane escape. By binding to polar residues in the conserved N-terminal region of PulG, we propose that PulM acts as chaperone to promote pseudopilin recruitment and coordinate its membrane extraction with subsequent steps of the fibre assembly process., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Type II secretion systems (T2SSs) promote secretion of folded proteins playing important roles in nutrient acquisition, adaptation and virulence of Gram-negative bacteria. Protein secretion is associated with the assembly of type 4 pilus (T4P)-like fibres called pseudopili. Initially membrane embedded, pseudopilin and T4 pilin subunits share conserved transmembrane segments containing an invariant Glu residue at the fifth position, E5. Mutations of E5 in major T4 pilins and in PulG, the major pseudopilin of the Klebsiella T2SS abolish fibre assembly and function. Among the four minor pseudopilins, only PulH required E5 for secretion of pullulanase, the substrate of the Pul T2SS. Mass-spectrometry analysis of pili resulting from the co-assembly of PulG(E5A) variant and PulG(WT) ruled out an E5 role in pilin processing and N-methylation. A bacterial two-hybrid analysis revealed interactions of the full-length pseudopilins PulG and PulH with the PulJ-PulI-PulK priming complex and with the assembly factors PulM and PulF. Remarkably, PulG(E5A) and PulH(E5A) variants were defective in interaction with PulM but not with PulF, and co-purification experiments confirmed the E5-dependent interaction between native PulM and PulG. These results reveal the role of E5 in a recruitment step critical for assembly of the functional T2SS, likely relevant to T4P assembly systems., (© 2016 John Wiley & Sons Ltd.)

An important goal in evolutionary biology is to understand the genetic changes underlying novel morphological structures. We investigated the origins of a complex wing pattern found among Amazonian Heliconius butterflies. Genome sequence data from 142 individuals across 17 species identified narrow regions associated with two distinct red colour pattern elements, dennis and ray. We hypothesise that these modules in non-coding sequence represent distinct cis-regulatory loci that control expression of the transcription factor optix, which in turn controls red pattern variation across Heliconius. Phylogenetic analysis of the two elements demonstrated that they have distinct evolutionary histories and that novel adaptive morphological variation was created by shuffling these cis-regulatory modules through recombination between divergent lineages. In addition, recombination of modules into different combinations within species further contributes to diversity. Analysis of the timing of diversification in these two regions supports the hypothesis of introgression moving regulatory modules between species, rather than shared ancestral variation. The dennis phenotype introgressed into Heliconius melpomene at about the same time that ray originated in this group, while ray introgressed back into H. elevatus much more recently. We show that shuffling of existing enhancer elements both within and between species provides a mechanism for rapid diversification and generation of novel morphological combinations during adaptive radiation.

The Klebsiella lipoprotein pullulanase (PulA) is exported to the periplasm, triacylated, and anchored via lipids in the inner membrane (IM) prior to its transport to the bacterial surface through a type II secretion system (T2SS). X-Ray crystallography and atomistic molecular dynamics (MD) simulations of PulA in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) model membrane provided an unprecedented molecular view of an N-terminal unstructured tether and the IM lipoprotein retention signal, and revealed novel interactions with the IM via N-terminal immunoglobulin-like domains in PulA. An efficiently secreted nonacylated variant (PulANA) showed similar peripheral membrane association during MD simulations, consistent with the binding of purified PulANA to liposomes. Remarkably, combined X-ray, MD, and functional studies identified a novel subdomain, Ins, inserted in the α-amylase domain, which is required for PulA secretion. Available data support a model in which PulA binding to the IM promotes interactions with the T2SS, possibly via the Ins subdomain., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

5-Ethynyl-2'-deoxyuridine (EdU) incorporation is becoming the gold standard method for in vitro and in vivo visualization of proliferating cells. The small size of the fluorescent azides used for detection results in a high degree of specimen penetration. It can be used to easily detect DNA replication in large tissue samples or organ explants with low proliferation and turnover of cells formerly believed to be in a "terminal" state of differentiation. Here we describe a protocol for the localization and identification of proliferating cells in quiescent or injured pulmonary vasculature, in a model of pulmonary veno-occlusive disease (PVOD). PVOD is an uncommon form of pulmonary hypertension characterized by progressive obstruction of small pulmonary veins. We previously reported that mitomycin-C (MMC) therapy is associated with PVOD in human. We demonstrated that MMC can induce PVOD in rats, which currently represents the sole animal model that recapitulates human PVOD lesions. Using the EdU assay, we demonstrated that MMC-exposed lungs displayed areas of exuberant microvascular endothelial cell proliferation which mimics pulmonary capillary hemangiomatosis, one of the pathologic hallmarks of human PVOD. In vivo pulmonary cell proliferation measurement represents an interesting methodology to investigate the potential efficacy of therapies aimed at normalizing pathologic angioproliferation.

How common is hybridization between species and what effect does it have on the evolutionary process? Can hybridization generate new species and what indeed is a species? In this issue, Gompert et al. (2014) show how massive, genome-scale data sets can be used to shed light on these questions. They focus on the Lycaeides butterflies, and in particular, several populations from the western USA, which have characteristics suggesting that they may contain hybrids of two or more different species (Gompert et al. 2006). They demonstrate that these populations do contain mosaic genomes made up of components from different parental species. However, this appears to have been largely driven by historical admixture, with more recent processes appearing to be isolating the populations from each other. Therefore, these populations are on their way to becoming distinct species (if they are not already) but have arisen following extensive hybridization between other distinct populations or species (Fig. 1)., (© 2014 John Wiley & Sons Ltd.)

Asthma is a common debilitating inflammatory lung disease affecting over 200 million people worldwide. Here, we investigated neurogenic components involved in asthmatic-like attacks using the ovalbumin-sensitized murine model of the disease, and identified a specific population of neurons that are required for airway hyperreactivity. We show that ablating or genetically silencing these neurons abolished the hyperreactive broncho-constrictions, even in the presence of a fully developed lung inflammatory immune response. These neurons are found in the vagal ganglia and are characterized by the expression of the transient receptor potential vanilloid 1 (TRPV1) ion channel. However, the TRPV1 channel itself is not required for the asthmatic-like hyperreactive airway response. We also demonstrate that optogenetic stimulation of this population of TRP-expressing cells with channelrhodopsin dramatically exacerbates airway hyperreactivity of inflamed airways. Notably, these cells express the sphingosine-1-phosphate receptor 3 (S1PR3), and stimulation with a S1PR3 agonist efficiently induced broncho-constrictions, even in the absence of ovalbumin sensitization and inflammation. Our results show that the airway hyperreactivity phenotype can be physiologically dissociated from the immune component, and provide a platform for devising therapeutic approaches to asthma that target these pathways separately.

The closely related bacterial type II secretion (T2S) and type IV pilus (T4P) systems are sophisticated machines that assemble dynamic fibers promoting protein transport, motility, or adhesion. Despite their essential role in virulence, the molecular mechanisms underlying helical fiber assembly remain unknown. Here, we use electron microscopy and flexible modeling to study conformational changes of PulG pili assembled by the Klebsiella oxytoca T2SS. Neural network analysis of 3,900 pilus models suggested a transition path toward low-energy conformations driven by progressive increase in fiber helical twist. Detailed predictions of interprotomer contacts along this path were tested by site-directed mutagenesis, pilus assembly, and protein secretion analyses. We demonstrate that electrostatic interactions between adjacent protomers (P-P+1) in the membrane drive pseudopilin docking, while P-P+3 and P-P+4 contacts determine downstream fiber stabilization steps. These results support a model of a spool-like assembly mechanism for fibers of the T2SS-T4P superfamily., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objective: To determine whether different health care systems may affect reproductive decision-making among patients with Multiple Sclerosis (MS), we describe the reproductive practices and attitudes of Canadian MS patients ascertained from the multidisciplinary MS Clinic at Hôpital Notre-Dame in Montreal, Quebec (NDMSC), in comparison to those of matched American self-registrants from the database of the North American Research Committee on Multiple Sclerosis (NARCOMS)., Methods: A total of 665 self-administered questionnaires on reproductive practices were sent out to eligible attendees attending the NDMSC. The short questionnaires were completed and returned to the authors in an anonymous format for analysis., Results: A total of 459 completed questionnaires were returned. The majority of NDMSC respondents (72.5%) and NARCOMS subset (75.2% females), did not encounter a pregnancy following diagnosis of MS. The most common MS-related reason for this decision was "symptoms interfering with parenting" (75.0% for the NDMSC, 72.6% for the NARCOMS). The most commonly reported non-MS-related reason was "a completed family" by the time of diagnosis in both the NDMSC and NARCOMS subset (58.0%, 40.4%, respectively). Concerns about financial issues both related and unrelated to MS were also commonly reported by males and females in both cohorts but significantly more so among the NARCOMS participants., Conclusion: These results indicate that reproductive decisions of MS patients are highly affected by their illness and its associated disability, regardless of the available health care program. Health care providers should discuss their patients' reproductive needs and perceptions to help them make more informed decisions.

The highly enantioselective catalytic asymmetric addition of aryl and alkenylboronic acids to N-benzylnicotinate salt 1 is described. The dihydropyridine 2 reaction products can be converted to synthetically useful piperidines. Application of the methodology to the preparation of enantioenriched quaternary chiral centers is also discussed.

The mimetic wing patterns of Heliconius butterflies are an excellent example of both adaptive radiation and convergent evolution. Alleles at the HmYb and HmSb loci control the presence/absence of hindwing bar and hindwing margin phenotypes respectively between divergent races of Heliconius melpomene, and also between sister species. Here, we used fine-scale linkage mapping to identify and sequence a BAC tilepath across the HmYb/Sb loci. We also generated transcriptome sequence data for two wing pattern forms of H. melpomene that differed in HmYb/Sb alleles using 454 sequencing technology. Custom scripts were used to process the sequence traces and generate transcriptome assemblies. Genomic sequence for the HmYb/Sb candidate region was annotated both using the MAKER pipeline and manually using transcriptome sequence reads. In total, 28 genes were identified in the HmYb/Sb candidate region, six of which have alternative splice forms. None of these are orthologues of genes previously identified as being expressed in butterfly wing pattern development, implying previously undescribed molecular mechanisms of pattern determination on Heliconius wings. The use of next-generation sequencing has therefore facilitated DNA annotation of a poorly characterized genome, and generated hypotheses regarding the identity of wing pattern at the HmYb/Sb loci.

Clinical evaluative research are far too few. In this article, the authors describe a research process likely to favor its multiplication. They report on a case study of a process resembling a cooperative action-research led by a group of clinicians in pedopsychiatry. With the results and in the light of caracteristics of action-research, they explain why and how this group of clinicians has succeeded in establishing a research process. The lessons drawned from this experience are numerous. The authors conclude by proposing a cooperative action-research as a model that all clinicians could apply to a clinical study.

Unlabelled: To assess the role of postoperative analgesia on myocardial ischemia after aortic surgery, we compared intravenous patient-controlled analgesia (PCA) with thoracic epidural analgesia (TEA). One hundred twenty-four patients were prospectively randomized to the PCA or TEA group. In the TEA group, a T6-7 or T7-8 epidural catheter was inserted before the induction of general anesthesia. Within 1 h of the end of surgery, analgesia and 24-h two-channel Holter monitoring were begun. Myocardial ischemia was defined as ST segment depression > or = 1 mm, 0.06 s after the J point, and lasting for more than 1 min. In the PCA group, a bolus of morphine, 0.05 mg/kg, was given, followed by 0.02 mg/kg of morphine on demand every 10 min. Bupivacaine 0.125% and fentanyl 10 microg/mL was used in the TEA group. Analgesics were titrated to maintain a visual analog scale score < or = 3. The overall incidence of myocardial ischemia was 18.4%-18.2% for TEA and 18.6% for PCA (P = not significant). There were no differences between the groups in the total duration of ischemia per patient (22.2 +/- 119.8 min for TEA and 20.5 +/- 99 min for PCA) and the number of episodes per patient (0.69 +/- 2.1 for TEA and 1.2 +/- 4.9 for PCA). Twenty-three patients had an adverse cardiac outcome, although there were no differences between the groups. The postoperative pain control was superior with TEA. In these patients undergoing elective aortic surgery, the use of postoperative TEA did not result in a lower incidence of early myocardial ischemia compared with intravenous PCA with morphine, despite better analgesia with TEA., Implications: Postoperative myocardial ischemia is associated with adverse cardiac outcome. Using Holter monitoring after aortic surgery, this study shows that the use of thoracic epidural analgesia with bupivacaine and fentanyl did not result in a lower incidence of myocardial ischemia compared with intravenous patient-controlled analgesia with morphine.

Changes in Ontario's political, social and economic environments have necessitated an unprecedented transformation in the health care system. The change in focus from the individual to the community now includes core units such as families, groups and communities. Visiting nurses, public health nurses and community health nurses have worked in Community Health Centres (CHCs) since 1970. However, the role of nurses working in these centres has not been clearly defined in the literature. Nor is there is a general consensus on their title. Nurse practitioners, primary care nurses or community health nurses are all used. As well, there is no existing educational program in Ontario that trains this type of nurse. This article discusses and gives examples of nurses working in community health, whose primary clinical expertise is in using community based and community development program strategies to plan health programs. These programs are specifically developed to address the health needs of the communities they serve--in this case, Toronto's francophone community. Also demonstrated are new approaches to nursing care within a community setting. From health promotion to disease prevention, from community development to research, the practice of community health nursing is complex and exciting.

The management of asymptomatic gallstones discovered during abdominal surgery is controversial. Should cholecystectomy be performed en passant? The authors report a 4-year survey of 109 patients with asymptomatic cholelithiasis who underwent surgery for other abdominal conditions: colorectal (31), gastric (24), vascular (20), gynecologic (21) and miscellaneous (13). Cholelithiasis was established preoperatively by ultrasonography in 52 of 55 examinations (95%). In the other 54, the gallstones were discovered at operation. Cholecystectomy was performed in 78 patients and in 31 the gallbladder was left in place. In the former group, 11 (14%) had complications, 2 being attributable to the cholecystectomy. Intraoperative cholangiograms were obtained in 43 and led to common-bile-duct explorations in 8. Common-bile-duct stones were found in seven. In the non-cholecystectomized group, three died postoperatively and three were lost to follow-up. Twelve of the remaining 25 are still asymptomatic and 13 have had symptoms: 7 underwent cholecystectomy (4 for acute cholecystitis) between 2 weeks and 11 months after the initial laparotomy. Because of the low morbidity and the relatively high number of cholecystectomies that were subsequently necessary, the authors recommend cholecystectomy en passant unless there is a specific contraindication. They also recommend ultrasonography before major gastrointestinal or vascular surgery in order to plan for cholecystectomy.