Testing the potential contribution of Wolbachia to speciation when cytoplasmic incompatibility becomes associated with host-related reproductive isolation.

Endosymbiont-induced cytoplasmic incompatibility (CI) may play an important role in arthropod speciation. However, whether CI consistently becomes associated or coupled with other host-related forms of reproductive isolation (RI) to impede the transfer of endosymbionts between hybridizing populations and further the divergence process remains an open question. Here, we show that varying degrees of pre- and postmating RI exist among allopatric populations of two interbreeding cherry-infesting tephritid fruit flies (Rhagoletis cingulata and R. indifferens) across North America. These flies display allochronic and sexual isolation among populations, as well as unidirectional reductions in egg hatch in hybrid crosses involving southwestern USA males. All populations are infected by a Wolbachia strain, wCin2, whereas a second strain, wCin3, only co-infects flies from the southwest USA and Mexico. Strain wCin3 is associated with a unique mitochondrial DNA haplotype and unidirectional postmating RI, implicating the strain as the cause of CI. When coupled with nonendosymbiont RI barriers, we estimate the strength of CI associated with wCin3 would not prevent the strain from introgressing from infected southwestern to uninfected populations elsewhere in the USA if populations were to come into secondary contact and hybridize. In contrast, cytoplasmic-nuclear coupling may impede the transfer of wCin3 if Mexican and USA populations were to come into contact. We discuss our results in the context of the general paucity of examples demonstrating stable Wolbachia hybrid zones and whether the spread of Wolbachia among taxa can be constrained in natural hybrid zones long enough for the endosymbiont to participate in speciation.

Genomically correlated trait combinations and antagonistic selection contributing to counterintuitive genetic patterns of adaptive diapause divergence in Rhagoletis flies.

Adaptation to novel environments can result in unanticipated genomic responses to selection. Here, we illustrate how multifarious, correlational selection helps explain a counterintuitive pattern of genetic divergence between the recently derived apple- and ancestral hawthorn-infesting host races of Rhagoletis pomonella (Diptera: Tephritidae). The apple host race terminates diapause and emerges as adults earlier in the season than the hawthorn host race, to coincide with the earlier fruiting phenology of their apple hosts. However, alleles at many loci associated with later emergence paradoxically occur at higher frequencies in sympatric populations of the apple compared to the hawthorn race. We present genomic evidence that historical selection over geographically varying environmental gradients across North America generated genetic correlations between two life history traits, diapause intensity and diapause termination, in the hawthorn host race. Moreover, the loci associated with these life history traits are concentrated in genomic regions in high linkage disequilibrium (LD). These genetic correlations are antagonistic to contemporary selection on local apple host race populations that favours increased initial diapause depth and earlier, not later, diapause termination. Thus, the paradox of apple flies appears due, in part, to pleiotropy or linkage of alleles associated with later adult emergence and increased initial diapause intensity, the latter trait strongly selected for by the earlier phenology of apples. Our results demonstrate how understanding of multivariate trait combinations and the correlative nature of selective forces acting on them can improve predictions concerning adaptive evolution and help explain seemingly counterintuitive patterns of genetic diversity in nature.

Perceived barriers to early goal-directed mobility in the intensive care unit: Results of a quality improvement evaluation.

BACKGROUND: A multicentre randomised trial demonstrated improved outcomes for intensive care unit (ICU) patients using early, goal-directed mobility implemented by nurses. OBJECTIVES: The aim of the study was to evaluate barriers to nursing mobility, using a validated survey, during an ongoing quality improvement (QI) project (2019) in a medical ICU and determine changes from the pre-QI (2017) baseline. METHODS: Nurses, nurse practitioners, physician assistants, and clinical technicians completed the 26-item Patient Mobilization Attitudes and Beliefs Survey for the ICU (PMABS-ICU). An overall score and three subscale scores (knowledge, attitudes, behaviour), each ranging from 0 to 100, were calculated; higher scores indicated greater barriers. RESULTS: Seventy-five (93% response rate) nurses, eight (100%) nurse practitioners and physician assistants, and 11 (100%) clinical technicians completed the PMABS-ICU. For all respondents (N = 94), the mean (standard deviation) overall PMABS-ICU score was 32 (8) and the knowledge, attitudes and behaviour subscale scores were 22 (11), 33 (11), and 34 (8), respectively. Among all respondents completing the survey in both 2017 and 2019 (N = 46), there was improvement in the mean (95% confidence interval) overall score [-3.1 (-5.8, -0.5); p = .022] and in the knowledge [-5.1 (-8.9, -1.3); p = .010] and attitudes [-3.9 (-7.3, -0.6); p = .023] subscale scores. Among all respondents (N = 48) taking the PMABS-ICU for the first time in 2019 compared with those taking the survey before the QI project in 2017 (N = 99), there was improvement in the mean (95% confidence interval) overall score [-3.8 (-6.5, -1.1); p = .007] and in the knowledge [-6.9 (-11.0, -2.7); p = .001] and attitude [-4.3 (-8.1, -0.5); p = .027] subscale scores. CONCLUSIONS: Using a validated survey administered to ICU nurses and other staff, before and during a structured QI project, there was a decrease in perceived barriers to mobility. Reduced barriers among those taking the survey for the first time during the QI project compared with those taking the survey before the QI project suggests a positive culture change supporting early, goal-directed mobility implemented by nurses.

Perceived Barriers to Mobility in a Medical ICU: The Patient Mobilization Attitudes & Beliefs Survey for the ICU.

PURPOSE: Early mobilization in the intensive care unit (ICU) can improve patient outcomes but has perceived barriers to implementation. As part of an ongoing structured quality improvement project to increase mobilization of medical ICU patients by nurses and clinical technicians, we adapted the existing, validated Patient Mobilization Attitudes & Beliefs Survey (PMABS) for the ICU setting and evaluated its performance characteristics and results. MATERIALS AND METHODS: The 26-item PMABS adapted for the ICU (PMABS-ICU) was administered as an online survey to 163 nurses, clinical technicians, respiratory therapists, attending and fellow physicians, nurse practitioners, and physician assistants in one medical ICU. We evaluated the overall and subscale (knowledge, attitude, and behavior) scores and compared these scores by respondent characteristics (clinical role and years of work experience). RESULTS: The survey response rate was 96% (155/163). The survey demonstrated acceptable discriminant validity and acceptable internal consistency for the overall scale (Cronbach α: 0.82, 95% confidence interval: 0.76-0.85), with weaker internal consistency for all subscales (Cronbach α: 0.62-0.69). Across all respondent groups, the overall barrier score (range: 1-100) was relatively low, with attending physicians perceiving the lowest barriers (median [interquartile range]: 30 [28-34]) and nurses perceiving the highest (37 [31-40]). Within the first 10 years of work experience, greater experience was associated with a lower overall barrier score (-0.8 for each additional year; P = 0.02). CONCLUSIONS: In our medical ICU, across 6 different clinical roles, there were relatively low perceived barriers to patient mobility, with greater work experience over the first 10 years being associated with lower perceived barriers. As part of a structured quality improvement project, the PMABS-ICU may be valuable in assisting to identify specific perceived barriers for consideration in designing mobility interventions for the ICU setting.

Radiologic Improvement After Early Medical Intervention in Localised Facial Morphea.

We report the case of a young girl who presented with hemiparesis, seizures, and subtle features consistent with a linear form of facial morphea (en coup de sabre). She was treated with pulsed parenteral steroids and oral steroids and started on methotrexate. Magnetic resonance imaging results and neurologic problems improved after 6 months. Switching off inflammation early in the course of disease seemed to reverse some of the central nervous system changes. Assessment of children with unexplained hemiparesis and seizures should include careful examination of the face and scalp, looking for subtle signs of skin change and asymmetry. This is one of the few reported cases of neuroradiologic improvement after immunosuppressive treatment in a child with en coup de sabre.

The adverse effect profile of oral azathioprine in pediatric atopic dermatitis, and recommendations for monitoring.

BACKGROUND: Azathioprine is efficacious in the treatment of severe childhood atopic dermatitis; however, robust data on adverse effects in this population are lacking. OBJECTIVE: We sought to assess adverse effects of azathioprine treatment in a pediatric atopic dermatitis cohort, and make recommendations for monitoring based on these data. METHODS: Blood test results for all 82 children prescribed oral azathioprine for atopic dermatitis in our department between 2010 and 2012 were collated prospectively, and clinical notes were reviewed retrospectively. RESULTS: Mean age at commencing azathioprine was 8.3 years (SEM 0.4). Mean maximum doses were 2.4 mg/kg (SEM 0.1) and 1.5 mg/kg (SEM 0.1) for normal and reduced serum thiopurine-S-methyltransferase levels, respectively. Adverse effects on blood indices occurred in 34 of 82 patients (41%), with pronounced effects in 18 of 82 (22%) after a median time of 0.4 years. Two patients stopped therapy as a result of abnormal blood indices. Clinical adverse effects occurred in 16 of 82 (20%), two resulting in cessation of therapy. Incidence of adverse effects was unaffected by age, sex, thiopurine-S-methyltransferase level, and drug dose on multivariate regression. LIMITATIONS: Comparison with other studies is limited by varying definitions of adverse effects. CONCLUSION: Oral azathioprine was associated with few pronounced adverse effects for the duration of use and dosage in this cohort. Recommendations for monitoring are made.

Bullous pemphigoid induced by hydrochlorothiazide therapy.

The most common subepidermal blistering disorder, bullous pemphigoid (BP) typically occurs in the elderly without any obvious inciting event. 1 Anti-basement membrane zone antibodies are typically detected on direct and indirect immunofluorescence studies. 2 A flu-like prodromal phase with a non-specific urticarial dermatitis may herald the development of the more characteristic tense bullae. 3 Obtaining a thorough medication history is important as a number of pharmacological agents have been reported to trigger this same phenomenon. We report a case of generalized BP induced by hydrochlorothiazide therapy in a 32-year-old male.

High-pressure effect on the dynamics of solvated peptides.

The dynamics of peptides has a direct connection to how quickly proteins can alter their conformations. The speed of exploring the free energy landscape depend on many factors, including the physical parameters of the environment, such as pressure and temperature. We performed a series of molecular dynamics simulations to investigate the pressure-temperature effects on peptide dynamics, especially on the torsional angle and peptide-water hydrogen bonding (H-bonding) dynamics. Here, we show that the dynamics of the omega angle and the H-bonding dynamics between water and the peptide are affected by pressure. At high temperature (500 K), both the dynamics of the torsional angle ω and H-bonding slow down significantly with increasing pressure, interestingly, at approximately the same rate. However, at a lower temperature of 300 K, the observed trend on H-bonding dynamics as a function of pressure reverses, i.e., higher pressure speeds up H-bonding dynamics.

Stability and sugar recognition ability of ricin-like carbohydrate binding domains.

Lectins are a class of proteins known for their novel binding to saccharides. Understanding this sugar recognition process can be crucial in creating structure-based designs of proteins with various biological roles. We focus on the sugar binding of a particular lectin, ricin, which has two ß-trefoil carbohydrate-binding domains (CRDs) found in several plant protein toxins. The binding ability of possible sites of ricin-like CRD has been puzzling. The apo and various (multiple) ligand-bound forms of the sugar-binding domains of ricin were studied by molecular dynamics simulations. By evaluating structural stability, hydrogen bond dynamics, flexibility, and binding energy, we obtained a detailed picture of the sugar recognition of the ricin-like CRD. Unlike what was previously believed, we found that the binding abilities of the two known sites are not independent of each other. The binding ability of one site is positively affected by the other site. While the mean positions of different binding scenarios are not altered significantly, the flexibility of the binding pockets visibly decreases upon multiple ligand binding. This change in flexibility seems to be the origin of the binding cooperativity. All the hydrogen bonds that are strong in the monoligand state are also strong in the double-ligand complex, although the stability is much higher in the latter form due to cooperativity. These strong hydrogen bonds in a monoligand state are deemed to be the essential hydrogen bonds. Furthermore, by examining the structural correlation matrix, the two domains are structurally one entity. Galactose hydroxyl groups, OH4 and OH3, are the most critical parts in both site 1α and site 2γ recognition.

Arterio-venous malformations of the ear: Description of distinct anatomical presentation and multidisciplinary management approach.

BACKGROUND: Arterio-venous malformations (AVMs) of the ear are a rare entity and their management should be decided in a dedicated multidisciplinary team (MDT) setting. The aim of this study is to describe the distinct anatomical patterns of the auricular AVMs in our unit and propose a combined interventional radiological and surgical approach. MATERIALS AND METHODS: All consecutive patients presenting with AVMs of the ear and reviewed by the Vascular Anomalies MDT between 2014 and 2019 were included in this study. Signs, symptoms, diagnostic investigations and operative findings were collected prospectively. RESULTS: After reviewing our nine patients, we identified four anatomical patterns of auricular AVMs: I: involves just a component of the ear and should undergo embolization followed by excision and reconstruction without significant loss of form; II: affects the superior two-thirds of the ear, sparing the lobule and part of the conchal bowl; these patients should undergo embolization, excision and monitoring before formal reconstruction of the ear is offered; III: involves the entire ear and should undergo embolization and pinnectomy; if there is no recurrence, the patients can be offered either a carved-rib cartilage reconstruction or a prosthesis, depending on the quality of the surrounding soft-tissues; IV: involves the ear and surrounding tissue, making surgical management and subsequent reconstruction extensive. CONCLUSION: The management of auricular AVMs is based on the extent of the ear involved. We feel that our combined interventional radiological and surgical approach will aid the management of these complex patients.

Cognitive Stimulation in an Intensive Care Unit: A Qualitative Evaluation of Barriers to and Facilitators of Implementation.

BACKGROUND: Delirium in the intensive care unit is associated with poor patient outcomes. Recent studies support nonpharmacological therapy, including cognitive stimulation, to address delirium. Understanding barriers to cognitive stimulation implemented by nurses during clinical care is essential to translating evidence into practice. OBJECTIVE: To use qualitative methods through a structured quality improvement project to understand nurses' perceived barriers to implementing a cognitive stimulation intervention in a medical intensive care unit. METHODS: Data were collected through semistructured interviews with nurses in a medical intensive care unit. Data were categorized into themes by using thematic analysis and the Consolidated Framework for Implementation Research. During cognitive stimulation, nurses reviewed with patients a workbook of evidence-based tasks (focused on math, alertness, motor skills, visual perception, memory, problem-solving, and language). RESULTS: The 23 nurses identified 62 barriers to and 26 facilitators of cognitive stimulation. These data were summarized into 12 barrier and 9 facilitator themes corresponding to the following Consolidated Framework for Implementation Research domains: Intervention Characteristics, Outer Setting, Inner Setting, and Characteristics of Individuals. Nurses also identified several facilitators within the Process domain. Patient-specific variables, including sedation, were the most frequently reported barriers. Other barriers included cognitive stimulation not being prioritized, nursing staff-related issues, documentation burden, and a lack of understanding of, or appreciation for, the evidence supporting cognitive stimulation. CONCLUSIONS: Implementation of cognitive stimulation requires a multidisciplinary approach to address perceived barriers arising from the organization, context, and individuals associated with the intervention, as well as the intervention itself.

Rapid and repeatable host plant shifts drive reproductive isolation following a recent human-mediated introduction of the apple maggot fly, Rhagoletis pomonella.

Ecological speciation via host-shifting is often invoked as a mechanism for insect diversification, but the relative importance of this process is poorly understood. The shift of Rhagoletis pomonella in the 1850s from the native downy hawthorn, Crataegus mollis, to introduced apple, Malus pumila, is a classic example of sympatric host race formation, a hypothesized early stage of ecological speciation. The accidental human-mediated introduction of R. pomonella into the Pacific Northwest (PNW) in the late 1970s allows us to investigate how novel ecological opportunities may trigger divergent adaptation and host race formation on a rapid timescale. Since the introduction, the fly has spread in the PNW, where in addition to apple, it now infests native black hawthorn, Crataegus douglasii, and introduced ornamental hawthorn, Crataegus monogyna. We use this "natural experiment" to test for genetic differentiation among apple, black, and ornamental hawthorn flies co-occurring at three sympatric sites. We report evidence that populations of all three host-associations are genetically differentiated at the local level, indicating that partial reproductive isolation has evolved in this novel habitat. Our results suggest that conditions suitable for initiating host-associated divergence may be common in nature, allowing for the rapid evolution of new host races when ecological opportunity arises.

Evidence for spatial clines and mixed geographic modes of speciation for North American cherry-infesting Rhagoletis (Diptera: Tephritidae) flies.

An important criterion for understanding speciation is the geographic context of population divergence. Three major modes of allopatric, parapatric, and sympatric speciation define the extent of spatial overlap and gene flow between diverging populations. However, mixed modes of speciation are also possible, whereby populations experience periods of allopatry, parapatry, and/or sympatry at different times as they diverge. Here, we report clinal patterns of variation for 21 nuclear-encoded microsatellites and a wing spot phenotype for cherry-infesting Rhagoletis (Diptera: Tephritidae) across North America consistent with these flies having initially diverged in parapatry followed by a period of allopatric differentiation in the early Holocene. However, mitochondrial DNA (mtDNA) displays a different pattern; cherry flies at the ends of the clines in the eastern USA and Pacific Northwest share identical haplotypes, while centrally located populations in the southwestern USA and Mexico possess a different haplotype. We hypothesize that the mitochondrial difference could be due to lineage sorting but more likely reflects a selective sweep of a favorable mtDNA variant or the spread of an endosymbiont. The estimated divergence time for mtDNA suggests possible past allopatry, secondary contact, and subsequent isolation between USA and Mexican fly populations initiated before the Wisconsin glaciation. Thus, the current genetics of cherry flies may involve different mixed modes of divergence occurring in different portions of the fly's range. We discuss the need for additional DNA sequencing and quantification of prezygotic and postzygotic reproductive isolation to verify the multiple mixed-mode hypothesis for cherry flies and draw parallels from other systems to assess the generality that speciation may commonly involve complex biogeographies of varying combinations of allopatric, parapatric, and sympatric divergence.

Recognition and management of congenital ichthyosis in a low-income setting.

We report the case of a 3-week old girl in The Gambia who presented to hospital with an undiagnosed skin disorder evolving since birth. Using telemedicine to seek specialist dermatology advice abroad, she was diagnosed with and managed for suspected congenital lamellar ichthyosis. Poor early recognition and limited resources, for both acute and chronic care, created significant challenges to optimal management; these were overcome, in part, by adopting a common sense, back-to-basics approach to treatment and by empowering the parents to take ownership of their infant's daily skin and eye care. This case highlights key global health issues associated with managing chronic, often debilitating, paediatric dermatological conditions in a low-income setting; namely, poor access to important diagnostic tools and medications, lack of experience and expertise in the management of severe skin disease and its associated complications, absence of long-term community support, alternative health beliefs and risk of sociocultural stigma.

Geographic and Ecological Dimensions of Host Plant-Associated Genetic Differentiation and Speciation in the Rhagoletis cingulata (Diptera: Tephritidae) Sibling Species Group.

Ascertaining the causes of adaptive radiation is central to understanding how new species arise and come to vary with their resources. The ecological theory posits adaptive radiation via divergent natural selection associated with novel resource use; an alternative suggests character displacement following speciation in allopatry and then secondary contact of reproductively isolated but ecologically similar species. Discriminating between hypotheses, therefore, requires the establishment of a key role for ecological diversification in initiating speciation versus a secondary role in facilitating co-existence. Here, we characterize patterns of genetic variation and postzygotic reproductive isolation for tephritid fruit flies in the Rhagoletis cingulata sibling species group to assess the significance of ecology, geography, and non-adaptive processes for their divergence. Our results support the ecological theory: no evidence for intrinsic postzygotic reproductive isolation was found between two populations of allopatric species, while nuclear-encoded microsatellites implied strong ecologically based reproductive isolation among sympatric species infesting different host plants. Analysis of mitochondrial DNA suggested, however, that cytoplasmic-related reproductive isolation may also exist between two geographically isolated populations within R cingulata. Thus, ecology associated with sympatric host shifts and cytoplasmic effects possibly associated with an endosymbiont may be the key initial drivers of the radiation of the R. cingulata group.

STAT3-Deficient hyperimmunoglobulin E syndrome: report of a case with orofacial granulomatosis-like disease.

Hyperimmunoglobulin E syndrome (HIES) is a rare heterogeneous primary immunodeficiency disorder characterized by infections of the lung and skin, elevated serum immunoglobulin E, and involvement of soft and bony tissues. Autosomal dominant HIES and related disorders are caused by defects in the Janus activated kinase-signal transducer and activator of transcription signaling pathway, leading to reduced numbers of T helper cell type 17 and impaired production of interleukin (IL)-17 A, IL-17 F, and IL-22. In addition, neutrophils have chemotactic defects, resulting in impaired responses at skin and lung sites. We report here a case of orofacial granulomatosis-like disease in a teenage boy ultimately found to have autosomal dominant HIES caused by a heterozygous mutation in the STAT3 gene.

Identifying Barriers to Nurse-Facilitated Patient Mobility in the Intensive Care Unit.

BACKGROUND: Nurse-facilitated mobility of patients in the intensive care unit can improve outcomes. However, a gap exists between research findings and their implementation as part of routine clinical practice. Such a gap is often attributed, in part, to the barrier of lack of time. The Translating Evidence Into Practice model provides a framework for research implementation, including recommendations for identifying barriers to implementation via direct observation of clinical care. OBJECTIVES: To report on design, implementation, and outcomes of an approach to identify and understand lack of time as a barrier to nurse-facilitated mobility in the intensive care unit. METHODS: An interprofessional team designed the observational process and evaluated the resulting data by using qualitative content analysis. RESULTS: During three 4-hour observations of 2 nurses and 1 nursing technician, 194 distinct tasks were performed (ie, events). A total of 4 categories of nurses' work were identified: patient care (47% of observation time), provider communication (25%), documentation (18%), and down time (10%). In addition, 3 types of potential mobility events were identified: in bed, edge of bed, and out of bed. The 194 observed events included 34 instances (18%) of potential mobility events that could be implemented: in bed (53%), edge of bed (6%), and out of bed (41%). CONCLUSIONS: Nurses have limited time for additional clinical activities but may miss potentially important opportunities for facilitating patient mobility during existing patient care. The proposed method is feasible and helpful in empirically investigating barriers to nurse-facilitated patient mobility in the intensive care unit.