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Nickel Allergic Contact Dermatitis: Identification, Treatment, and Prevention

Nickel is a ubiquitous metal added to jewelry and metallic substances for its hardening properties and because it is inexpensive. Estimates suggest that at least 1.1 million children in the United States are sensitized to nickel. Nickel allergic contact dermatitis (Ni-ACD) is the most common cutaneous delayed-type hypersensitivity reaction worldwide. The incidence among children tested has almost quadrupled over the past 3 decades. The associated morbidities include itch, discomfort, school absence, and reduced quality of life. In adulthood, individuals with Ni-ACD may have severe disabling hand eczema. The increasing rate of Ni-ACD in children has been postulated to result from early and frequent exposure to metals with high amounts of nickel release (eg, as occurs with ear piercing or with products used daily in childhood such as toys, belt buckles, and electronics).

To reduce exposure to metal sources with high nickel release by prolonged and direct contact with human skin, Denmark and the European Union legislated a directive several decades ago with the goal of reducing high nickel release and the incidence of Ni-ACD. Since then, there has been a global reduction in incidence of Ni-ACD in population-based studies of adults and studies of children and young adults being tested for allergic contact dermatitis. These data point to nickel exposure as a trigger for elicitation of Ni-ACD and, further, provide evidence that legislation can have a favorable effect on the economic and medical health of a population.

This policy statement reviews the epidemiology, history, and appearances of Ni-ACD. Examples of sources of high nickel release are discussed to highlight how difficult it is to avoid this metal in modern daily lives. Treatments are outlined, and avoidance strategies are presented. Long-term epidemiological interventions are addressed. Advocacy for smarter nickel use is reviewed. The American Academy of Pediatrics supports US legislation that advances safety standards (as modeled by the European Union) that protect children from early and prolonged skin exposure to high–nickel-releasing items. Our final aim for this article is to aid the pediatric community in developing nickel-avoidance strategies on both individual and global levels.




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Children With Intellectual and Developmental Disabilities as Organ Transplantation Recipients

The demand for transplantable solid organs far exceeds the supply of deceased donor organs. Patient selection criteria are determined by individual transplant programs; given the scarcity of solid organs for transplant, allocation to those most likely to benefit takes into consideration both medical and psychosocial factors. Children with intellectual and developmental disabilities have historically been excluded as potential recipients of organ transplants. When a transplant is likely to provide significant health benefits, denying a transplant to otherwise eligible children with disabilities may constitute illegal and unjustified discrimination. Children with intellectual and developmental disabilities should not be excluded from the potential pool of recipients and should be referred for evaluation as recipients of solid organ transplants.




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Ames SG, Davis BS, Marin JR, L. Fink EL, Olson LM, Gausche-Hill M, Kahn JM. Emergency Department Pediatric Readiness and Mortality in Critically Ill Children. Pediatrics. 2019;144(3):e20190568




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Early and Often: The Need for Comprehensive Discussion of Treatment-Induced Cancer Late Effects




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Racial and Ethnic Differences in Emergency Department Pain Management of Children With Fractures

OBJECTIVES:

To test the hypotheses that minority children with long-bone fractures are less likely to (1) receive analgesics, (2) receive opioid analgesics, and (3) achieve pain reduction.

METHODS:

We performed a 3-year retrospective cross-sectional study of children <18 years old with long-bone fractures using the Pediatric Emergency Care Applied Research Network Registry (7 emergency departments). We performed bivariable and multivariable logistic regression to measure the association between patient race and ethnicity and (1) any analgesic, (2) opioid analgesic, (3) ≥2-point pain score reduction, and (4) optimal pain reduction (ie, to mild or no pain).

RESULTS:

In 21 069 visits with moderate-to-severe pain, 86.1% received an analgesic and 45.4% received opioids. Of 8533 patients with reassessment of pain, 89.2% experienced ≥2-point reduction in pain score and 62.2% experienced optimal pain reduction. In multivariable analyses, minority children, compared with non-Hispanic (NH) white children, were more likely to receive any analgesics (NH African American: adjusted odds ratio [aOR] 1.72 [95% confidence interval 1.51–1.95]; Hispanic: 1.32 [1.16–1.51]) and achieve ≥2-point reduction in pain (NH African American: 1.42 [1.14–1.76]; Hispanic: 1.38 [1.04–1.83]) but were less likely to receive opioids (NH African American: aOR 0.86 [0.77–0.95]; Hispanic: aOR 0.86 [0.76–0.96]) or achieve optimal pain reduction (NH African American: aOR 0.78 [0.67–0.90]; Hispanic: aOR 0.80 [0.67–0.95]).

CONCLUSIONS:

There are differences in process and outcome measures by race and ethnicity in the emergency department management of pain among children with long-bone fractures. Although minority children are more likely to receive analgesics and achieve ≥2-point reduction in pain, they are less likely to receive opioids and achieve optimal pain reduction.




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Teenage Use of Smartphone Applications for Menstrual Cycle Tracking




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Enhancing CPR During Transition From Prehospital to Emergency Department: A QI Initiative

BACKGROUND AND OBJECTIVES:

High-quality cardiopulmonary resuscitation (CPR) increases the likelihood of survival of pediatric out-of-hospital cardiac arrest (OHCA). Maintenance of high-quality CPR during transition of care between prehospital and pediatric emergency department (PED) providers is challenging. Our objective for this initiative was to minimize pauses in compressions, in alignment with American Heart Association recommendations, for patients with OHCA during the handoffs from prehospital to PED providers. We aimed to decrease interruptions in compressions during the first 2 minutes of PED care from 17 seconds (baseline data) to 10 seconds over 12 months. Our secondary aims were to decrease the length of the longest pause in compressions to <10 seconds and eliminate encounters in which time to defibrillator pad placement was >120 seconds.

METHODS:

Our multidisciplinary team outlined our theory for improvement and designed interventions aimed at key drivers. Interventions included specific roles and responsibilities, CPR handoff choreography, and empowerment of frontline providers. Data were abstracted from video recordings of patients with OHCA receiving manual CPR on arrival.

RESULTS:

We analyzed 33 encounters between March 2018 and July 2019. We decreased total interruptions from 17 to 12 seconds during the first 2 minutes and decreased the time of the longest single pause from 14 to 7 seconds. We saw a decrease in variability of time to defibrillator pad placement.

CONCLUSIONS:

Implementation of a quality improvement initiative involving CPR transition choreography resulted in decreased interruptions in compressions and decreased variability of time to defibrillator pad placement.




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Rates and Stability of Mental Health Disorders in Children Born Very Preterm at 7 and 13 Years

OBJECTIVES:

Children born very preterm (VPT) are at an increased risk of developing mental health (MH) disorders. Our aim for this study was to assess rates of MH disorders in children born VPT and term at 13 years of age and stability of MH disorders between ages 7 and 13 years by using a diagnostic measure.

METHODS:

Participants were from the Victorian Infant Brain Study longitudinal cohort and included 125 children born VPT (<30 weeks’ gestational age and/or <1250 g) and 49 children born term (≥37 weeks’ gestational age) and their families. Participants were followed-up at both 7 and 13 years, and the Development and Well-Being Assessment was administered to assess for MH disorders.

RESULTS:

Compared with term peers, 13-year-olds born VPT were more likely to meet criteria for any MH disorder (odds ratio 5.9; 95% confidence interval 1.71–20.03). Anxiety was the most common disorder in both groups (VPT = 14%; term = 4%), whereas attention-deficit/hyperactivity disorder carried the greatest differential elevated risk (odds ratio 5.6; 95% confidence interval 0.71–43.80). Overall rates of MH disorders remained stable between 7 and 13 years, although at an individual level, many participants shifted in or out of diagnostic categories over time.

CONCLUSIONS:

Children born VPT show higher rates of MH disorders than their term peers, with changing trajectories over time. Findings highlight the importance of early identification and ongoing assessment to support those with MH disorders in this population.




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Network Implementation of Guideline for Early Detection Decreases Age at Cerebral Palsy Diagnosis

BACKGROUND AND OBJECTIVES:

Early diagnosis of cerebral palsy (CP) is critical in obtaining evidence-based interventions when plasticity is greatest. In 2017, international guidelines for early detection of CP were published on the basis of a systematic review of evidence. Our study aim was to reduce the age at CP diagnosis throughout a network of 5 diverse US high-risk infant follow-up programs through consistent implementation of these guidelines.

METHODS:

The study leveraged plan-do-study-act and Lean methodologies. The primary outcome was age at CP diagnosis. Data were acquired during the corresponding 9-month baseline and quarterly throughout study. Balancing measures were clinic no-show rates and parent perception of the diagnosis visit. Clinic teams conducted strengths, weaknesses, opportunities, and threats analyses, process flow evaluations, standardized assessments training, and parent questionnaires. Performance of a 3- to 4-month clinic visit was a critical process step because it included a Hammersmith Infant Neurologic Examination, a General Movements Assessment, and standardized assessments of motor function.

RESULTS:

The age at CP diagnosis decreased from a weighted average of 19.5 (95% confidence interval 16.2 to 22.8) to 9.5 months (95% confidence interval 4.5 to 14.6), with P = .008; 3- to 4-month visits per site increased from the median (interquartile range) 14 (5.2–73.7) to 54 (34.5–152.0), with P < .001; and no-show rates were not different. Parent questionnaires revealed positive provider perception with improvement opportunities for information content and understandability.

CONCLUSIONS:

Large-scale implementation of international guidelines for early detection of CP is feasible in diverse high-risk infant follow-up clinics. The initiative was received positively by families and without adversely affecting clinic operational flow. Additional parent support and education are necessary.




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In Utero Antidepressants and Neurodevelopmental Outcomes in Kindergarteners

OBJECTIVES:

To determine if in utero selective serotonin reuptake inhibitor (SSRI) or selective serotonin norepinephrine inhibitor (SNRI) exposure is associated with developmental vulnerability in kindergarten among children whose mothers were diagnosed with prenatal mood or anxiety disorder.

METHODS:

Linkable administrative data were used to create a population-based cohort of 266 479 mother-child dyads of children born in Manitoba, Canada, between 1996 and 2014, with follow-up through 2015. The sample was restricted to mothers who had a mood or anxiety disorder diagnosis between 90 days before conception (N = 13 818). Exposed women had ≥2 SSRI or SNRI dispensations during pregnancy (n = 2055); unexposed mothers did not have a dispensation of an SSRI or SNRI during pregnancy (n = 10 017). The Early Development Instrument (EDI) was used to assess developmental health in kindergarten children. The EDI is a 104-component kindergarten teacher-administered questionnaire, encompassing 5 developmental domains.

RESULTS:

Of the 3048 children included in the study who met inclusion criteria and had an EDI, 21.43% of children in the exposed group were assessed as vulnerable on 2 or more domains versus 16.16% of children in the unexposed group (adjusted odds ratio = 1.43; 95% confidence interval 1.08–1.90). Children in the exposed group also had a significant risk of being vulnerable in language and/or cognition (adjusted odds ratio = 1.40; 95% confidence interval 1.03–1.90).

CONCLUSIONS:

Exposure to SSRIs or SNRIs during pregnancy was associated with an increased risk of developmental vulnerability and an increased risk of deficits in language and/or cognition. Replication of results is necessary before clinical implications can be reached.




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Developmental Support for Infants With Genetic Disorders

As the technical ability for genetic diagnosis continues to improve, an increasing number of diagnoses are made in infancy or as early as the neonatal period. Many of these diagnoses are known to be associated with developmental delay and intellectual disability, features that would not be clinically detectable at the time of diagnosis. Others may be associated with cognitive impairment, but the incidence and severity are yet to be fully described. These neonates and infants with genetic diagnoses therefore represent an emerging group of patients who are at high risk for neurodevelopmental disabilities. Although there are well-established developmental supports for high-risk infants, particularly preterm infants, after discharge from the NICU, programs specifically for infants with genetic diagnoses are rare. And although previous research has demonstrated the positive effect of early developmental interventions on outcomes among preterm infants, the impact of such supports for infants with genetic disorders who may be born term, remains to be understood. We therefore review the literature regarding existing developmental assessment and intervention approaches for children with genetic disorders, evaluating these in the context of current developmental supports postdischarge for preterm infants. Further research into the role of developmental support programs for early assessment and intervention in high-risk neonates diagnosed with rare genetic disorders is needed.




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Genetic Associations in Four Decades of Multienvironment Trials Reveal Agronomic Trait Evolution in Common Bean [Genetics of Complex Traits]

Multienvironment trials (METs) are widely used to assess the performance of promising crop germplasm. Though seldom designed to elucidate genetic mechanisms, MET data sets are often much larger than could be duplicated for genetic research and, given proper interpretation, may offer valuable insights into the genetics of adaptation across time and space. The Cooperative Dry Bean Nursery (CDBN) is a MET for common bean (Phaseolus vulgaris) grown for > 70 years in the United States and Canada, consisting of 20–50 entries each year at 10–20 locations. The CDBN provides a rich source of phenotypic data across entries, years, and locations that is amenable to genetic analysis. To study stable genetic effects segregating in this MET, we conducted genome-wide association studies (GWAS) using best linear unbiased predictions derived across years and locations for 21 CDBN phenotypes and genotypic data (1.2 million SNPs) for 327 CDBN genotypes. The value of this approach was confirmed by the discovery of three candidate genes and genomic regions previously identified in balanced GWAS. Multivariate adaptive shrinkage (mash) analysis, which increased our power to detect significant correlated effects, found significant effects for all phenotypes. Mash found two large genomic regions with effects on multiple phenotypes, supporting a hypothesis of pleiotropic or linked effects that were likely selected on in pursuit of a crop ideotype. Overall, our results demonstrate that statistical genomics approaches can be used on MET phenotypic data to discover significant genetic effects and to define genomic regions associated with crop improvement.




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Dominance Effects and Functional Enrichments Improve Prediction of Agronomic Traits in Hybrid Maize [Genomic Prediction]

Single-cross hybrids have been critical to the improvement of maize (Zea mays L.), but the characterization of their genetic architectures remains challenging. Previous studies of hybrid maize have shown the contribution of within-locus complementation effects (dominance) and their differential importance across functional classes of loci. However, they have generally considered panels of limited genetic diversity, and have shown little benefit from genomic prediction based on dominance or functional enrichments. This study investigates the relevance of dominance and functional classes of variants in genomic models for agronomic traits in diverse populations of hybrid maize. We based our analyses on a diverse panel of inbred lines crossed with two testers representative of the major heterotic groups in the U.S. (1106 hybrids), as well as a collection of 24 biparental populations crossed with a single tester (1640 hybrids). We investigated three agronomic traits: days to silking (DTS), plant height (PH), and grain yield (GY). Our results point to the presence of dominance for all traits, but also among-locus complementation (epistasis) for DTS and genotype-by-environment interactions for GY. Consistently, dominance improved genomic prediction for PH only. In addition, we assessed enrichment of genetic effects in classes defined by genic regions (gene annotation), structural features (recombination rate and chromatin openness), and evolutionary features (minor allele frequency and evolutionary constraint). We found support for enrichment in genic regions and subsequent improvement of genomic prediction for all traits. Our results suggest that dominance and gene annotations improve genomic prediction across diverse populations in hybrid maize.




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Development of the Proximal-Anterior Skeletal Elements in the Mouse Hindlimb Is Regulated by a Transcriptional and Signaling Network Controlled by Sall4 [Developmental and Behavioral Genetics]

The vertebrate limb serves as an experimental paradigm to study mechanisms that regulate development of the stereotypical skeletal elements. In this study, we simultaneously inactivated Sall4 using Hoxb6Cre and Plzf in mouse embryos, and found that their combined function regulates development of the proximal-anterior skeletal elements in hindlimbs. The Sall4; Plzf double knockout exhibits severe defects in the femur, tibia, and anterior digits, distinct defects compared to other allelic series of Sall4; Plzf. We found that Sall4 regulates Plzf expression prior to hindlimb outgrowth. Further expression analysis indicated that Hox10 genes and GLI3 are severely downregulated in the Sall4; Plzf double knockout hindlimb bud. In contrast, PLZF expression is reduced but detectable in Sall4; Gli3 double knockout limb buds, and SALL4 is expressed in the Plzf; Gli3 double knockout limb buds. These results indicate that Plzf, Gli3, and Hox10 genes downstream of Sall4, regulate femur and tibia development. In the autopod, we show that Sall4 negatively regulates Hedgehog signaling, which allows for development of the most anterior digit. Collectively, our study illustrates genetic systems that regulate development of the proximal-anterior skeletal elements in hindlimbs.




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Pits and CtBP Control Tissue Growth in Drosophila melanogaster with the Hippo Pathway Transcription Repressor Tgi [Developmental and Behavioral Genetics]

The Hippo pathway is an evolutionarily conserved signaling network that regulates organ size, cell fate, and tumorigenesis. In the context of organ size control, the pathway incorporates a large variety of cellular cues, such as cell polarity and adhesion, into an integrated transcriptional response. The central Hippo signaling effector is the transcriptional coactivator Yorkie, which controls gene expression in partnership with different transcription factors, most notably Scalloped. When it is not activated by Yorkie, Scalloped can act as a repressor of transcription, at least in part due to its interaction with the corepressor protein Tgi. The mechanism by which Tgi represses transcription is incompletely understood, and therefore we sought to identify proteins that potentially operate together with Tgi. Using an affinity purification and mass-spectrometry approach we identified Pits and CtBP as Tgi-interacting proteins, both of which have been linked to transcriptional repression. Both Pits and CtBP were required for Tgi to suppress the growth of the Drosophila melanogaster eye and CtBP loss suppressed the undergrowth of yorkie mutant eye tissue. Furthermore, as reported previously for Tgi, overexpression of Pits repressed transcription of Hippo pathway target genes. These findings suggest that Tgi might operate together with Pits and CtBP to repress transcription of genes that normally promote tissue growth. The human orthologs of Tgi, CtBP, and Pits (VGLL4, CTBP2, and IRF2BP2) have previously been shown to physically and functionally interact to control transcription, implying that the mechanism by which these proteins control transcriptional repression is conserved throughout evolution.




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Alcohol Causes Lasting Differential Transcription in Drosophila Mushroom Body Neurons [Developmental and Behavioral Genetics]

Repeated alcohol experiences can produce long-lasting memories for sensory cues associated with intoxication. These memories can problematically trigger relapse in individuals recovering from alcohol use disorder (AUD). The molecular mechanisms by which ethanol changes memories to become long-lasting and inflexible remain unclear. New methods to analyze gene expression within precise neuronal cell types can provide further insight toward AUD prevention and treatment. Here, we used genetic tools in Drosophila melanogaster to investigate the lasting consequences of ethanol on transcription in memory-encoding neurons. Drosophila rely on mushroom body (MB) neurons to make associative memories, including memories of ethanol-associated sensory cues. Differential expression analyses revealed that distinct transcripts, but not genes, in the MB were associated with experiencing ethanol alone compared to forming a memory of an odor cue associated with ethanol. Adult MB-specific knockdown of spliceosome-associated proteins demonstrated the necessity of RNA-processing in ethanol memory formation. These findings highlight the dynamic, context-specific regulation of transcription in cue-encoding neurons, and the lasting effect of ethanol on transcript usage during memory formation.




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Development of IFN-Stimulated Gene Expression from Embryogenesis through Adulthood, with and without Constitutive MDA5 Pathway Activation [INNATE IMMUNITY AND INFLAMMATION]

Key Points

  • The augmented ISG profile of RdRP mice develops largely postnatally.

  • Elevated ISG expression is then maintained through adulthood.

  • The ISG signature in adults requires persistent type I IFN signaling.




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    Apolipoprotein E Triggers Complement Activation in Joint Synovial Fluid of Rheumatoid Arthritis Patients by Binding C1q [INNATE IMMUNITY AND INFLAMMATION]

    Key Points

  • ApoE was found in complex with C4d in RA patient SF.

  • Deposited ApoE activates complement whereas ApoE in solution is inhibitory.

  • Posttranslational modifications alter ApoE's capacity to bind FH and C4BP.




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    Development and Characterization of an Avirulent Leishmania major Strain [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • Virulent and avirulent parasites significantly differ in their proteome profiles.

  • Avirulent parasites fail to inhibit CD40 signaling.

  • Avirulent parasite strain is a potential antileishmanial vaccine candidate.




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    GRASP55 Is Dispensable for Normal Hematopoiesis but Necessary for Myc-Dependent Leukemic Growth [IMMUNE SYSTEM DEVELOPMENT]

    Key Points

  • Golgi morphology and Grasp55 expression are regulated during hematopoiesis.

  • Hematopoiesis is not affected in Grasp55-deficient mice.

  • Grasp55 regulates Myc-transformed leukemic cell survival.




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    Innate-like CD27+CD45RBhigh {gamma}{delta} T Cells Require TCR Signaling for Homeostasis in Peripheral Lymphoid Organs [IMMUNE SYSTEM DEVELOPMENT]

    Key Points

  • E4 is an enhancer element that regulates transcriptions of TCR genes.

  • E4–/– mice have fewer CD27+CD45RBhigh V2+ T cells in peripheral organs.

  • Attenuation of TCR signal impairs homeostasis of T cells in peripheral organs.




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    Serine Phosphorylation of the STAT1 Transactivation Domain Promotes Autoreactive B Cell and Systemic Autoimmunity Development [AUTOIMMUNITY]

    Key Points

  • STAT1-pS727 is required for SLE-associated AFC, GC, and autoantibody responses.

  • STAT1-pS727 in B cells promotes autoimmune AFC, GC, and autoantibody responses.

  • STAT1-pS727 is not required for foreign Ag– or gut microbiota–driven responses.




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    Complement Deficiencies Result in Surrogate Pathways of Complement Activation in Novel Polygenic Lupus-like Models of Kidney Injury [AUTOIMMUNITY]

    Key Points

  • Novel TM lupus mouse strains develop spontaneous nephritis.

  • In C1q deficiency, kidney complement activation likely occurred via the LP.

  • In C3 deficiency, coagulation cascade contributed to kidney complement activation.




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    Early Endothelial Activation Precedes Glycocalyx Degradation and Microvascular Dysfunction in Experimentally Induced Plasmodium falciparum and Plasmodium vivax Infection [Host Response and Inflammation]

    Endothelial activation and microvascular dysfunction are key pathogenic processes in severe malaria. We evaluated the early role of these processes in experimentally induced Plasmodium falciparum and P. vivax infection. Participants were enrolled in induced blood-stage malaria clinical trials. Plasma osteoprotegerin, angiopoietin-2, and von Willebrand Factor (vWF) levels were measured as biomarkers of endothelial activation. Microvascular function was assessed using peripheral arterial tonometry and near-infrared spectroscopy, and the endothelial glycocalyx was assessed by sublingual videomicroscopy and measurement of biomarkers of degradation. Forty-five healthy, malaria-naive participants were recruited from 5 studies. Osteoprotegerin and vWF levels increased in participants following inoculation with P. vivax (n = 16) or P. falciparum (n = 15), with the angiopoietin-2 level also increasing in participants following inoculation with P. falciparum. For both species, the most pronounced increase was seen in osteoprotegerin. This was particularly marked in participants inoculated with P. vivax, where the osteoprotegerin level correlated with the levels of parasitemia and the malaria clinical score. There were no changes in measures of endothelial glycocalyx or microvascular function. Plasma biomarkers of endothelial activation increased in early P. falciparum and P. vivax infection and preceded changes in the endothelial glycocalyx or microvascular function. The more pronounced increase in osteoprotegerin suggests that this biomarker may play a role in disease pathogenesis.




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    Staphylococcus aureus Fibronectin Binding Protein A Mediates Biofilm Development and Infection [Bacterial Infections]

    Implanted medical device-associated infections pose significant health risks, as they are often the result of bacterial biofilm formation. Staphylococcus aureus is a leading cause of biofilm-associated infections which persist due to mechanisms of device surface adhesion, biofilm accumulation, and reprogramming of host innate immune responses. We found that the S. aureus fibronectin binding protein A (FnBPA) is required for normal biofilm development in mammalian serum and that the SaeRS two-component system is required for functional FnBPA activity in serum. Furthermore, serum-developed biofilms deficient in FnBPA were more susceptible to macrophage invasion, and in a model of biofilm-associated implant infection, we found that FnBPA is crucial for the establishment of infection. Together, these findings show that S. aureus FnBPA plays an important role in physical biofilm development and represents a potential therapeutic target for the prevention and treatment of device-associated infections.




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    Fluorescence-Reported Allelic Exchange Mutagenesis-Mediated Gene Deletion Indicates a Requirement for Chlamydia trachomatis Tarp during In Vivo Infectivity and Reveals a Specific Role for the C Terminus during Cellular Invasion [Cellular Microbiology: Pat

    The translocated actin recruiting phosphoprotein (Tarp) is a multidomain type III secreted effector used by Chlamydia trachomatis. In aggregate, existing data suggest a role of this effector in initiating new infections. As new genetic tools began to emerge to study chlamydial genes in vivo, we speculated as to what degree Tarp function contributes to Chlamydia’s ability to parasitize mammalian host cells. To address this question, we generated a complete tarP deletion mutant using the fluorescence-reported allelic exchange mutagenesis (FRAEM) technique and complemented the mutant in trans with wild-type tarP or mutant tarP alleles engineered to harbor in-frame domain deletions. We provide evidence for the significant role of Tarp in C. trachomatis invasion of host cells. Complementation studies indicate that the C-terminal filamentous actin (F-actin)-binding domains are responsible for Tarp-mediated invasion efficiency. Wild-type C. trachomatis entry into HeLa cells resulted in host cell shape changes, whereas the tarP mutant did not. Finally, using a novel cis complementation approach, C. trachomatis lacking tarP demonstrated significant attenuation in a murine genital tract infection model. Together, these data provide definitive genetic evidence for the critical role of the Tarp F-actin-binding domains in host cell invasion and for the Tarp effector as a bona fide C. trachomatis virulence factor.




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    Establishment of a Reverse Genetics System for Influenza D Virus [Genome Replication and Regulation of Viral Gene Expression]

    Influenza D virus (IDV) was initially isolated in the United States in 2011. IDV is distributed worldwide and is one of the causative agents of the bovine respiratory disease complex (BRDC), which causes high morbidity and mortality in feedlot cattle. The molecular mechanisms of IDV pathogenicity are still unknown. Reverse genetics systems are vital tools not only for studying the biology of viruses, but also for use in applications such as recombinant vaccine viruses. Here, we report the establishment of a plasmid-based reverse genetics system for IDV. We first verified that the 3'-terminal nucleotide of each 7-segmented genomic RNA contained uracil (U), contrary to previous reports, and we were then able to successfully generate recombinant IDV by cotransfecting 7 plasmids containing these genomic RNAs along with 4 plasmids expressing polymerase proteins and nucleoprotein into human rectal tumor 18G (HRT-18G) cells. The recombinant virus had a growth deficit compared to the wild-type virus, and we determined the reason for this growth difference by examining the genomic RNA content of the viral particles. We found that the recombinant virus incorporated an unbalanced ratio of viral RNA segments into particles compared to that of the wild-type virus, and thus we adjusted the amount of each plasmid used in transfection to obtain a recombinant virus with the same replicative capacity as the wild-type virus. Our work here in establishing a reverse genetics system for IDV will have a broad range of applications, including uses in studies focused on better understanding IDV replication and pathogenicity, as well as in those contributing to the development of BRDC countermeasures.

    IMPORTANCE The bovine respiratory disease complex (BRDC) causes high mortality and morbidity in cattle, causing economic losses worldwide. Influenza D virus (IDV) is considered to be a causative agent of the BRDC. Here, we developed a reverse genetics system that allows for the generation of IDV from cloned cDNAs and the introduction of mutations into the IDV genome. This reverse genetics system will become a powerful tool for use in studies related to understanding the molecular mechanisms of viral replication and pathogenicity and will also lead to the development of new countermeasures against the BRDC.




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    A New Gorilla Adenoviral Vector with Natural Lung Tropism Avoids Liver Toxicity and Is Amenable to Capsid Engineering and Vector Retargeting [Gene Delivery]

    Human adenoviruses have many attractive features for gene therapy applications. However, the high prevalence of preexisting immunity against these viruses in general populations worldwide has greatly limited their clinical utility. In addition, the most commonly used human adenovirus, human adenovirus subgroup C serotype 5 (HAd5), when systemically administered, triggers systemic inflammation and toxicity, with the liver being the most severely affected organ. Here, we evaluated the utility and safety of a new low-seroprevalence gorilla adenovirus (GAd; GC46) as a gene transfer vector in mice. Biodistribution studies revealed that systemically administered GAd had a selective and robust lung endothelial cell (EC) tropism with minimal vector expression throughout many other organs and tissues. Administration of a high dose of GAd accomplished extensive transgene expression in the lung yet elicited no detectable inflammatory histopathology in this organ. Furthermore, GAd, unlike HAd5, did not exhibit hepatotropism or induce liver inflammatory toxicity in mice, demonstrating the exceptional safety profile of the vector vis-à-vis systemic utility. We further demonstrated that the GAd capsid fiber shared the flexibility of the HAd5 equivalent for permitting genetic modification; GAd with the pan-EC-targeting ligand myeloid cell-binding peptide (MBP) incorporated in the capsid displayed a reduced lung tropism and efficiently retargeted gene expression to vascular beds in other organs.

    IMPORTANCE In the aggregate, our mouse studies suggest that GAd is a promising gene therapy vector that utilizes lung ECs as a source of therapeutic payload production and a highly desirable toxicity profile. Further genetic engineering of the GAd capsid holds the promise of in vivo vector tropism modification and targeting.




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    Experimental Evolution To Isolate Vaccinia Virus Adaptive G9 Mutants That Overcome Membrane Fusion Inhibition via the Vaccinia Virus A56/K2 Protein Complex [Virus-Cell Interactions]

    For cell entry, vaccinia virus requires fusion with the host membrane via a viral fusion complex of 11 proteins, but the mechanism remains unclear. It was shown previously that the viral proteins A56 and K2 are expressed on infected cells to prevent superinfection by extracellular vaccinia virus through binding to two components of the viral fusion complex (G9 and A16), thereby inhibiting membrane fusion. To investigate how the A56/K2 complex inhibits membrane fusion, we performed experimental evolutionary analyses by repeatedly passaging vaccinia virus in HeLa cells overexpressing the A56 and K2 proteins to isolate adaptive mutant viruses. Genome sequencing of adaptive mutants revealed that they had accumulated a unique G9R open reading frame (ORF) mutation, resulting in a single His44Tyr amino acid change. We engineered a recombinant vaccinia virus to express the G9H44Y mutant protein, and it readily infected HeLa-A56/K2 cells. Moreover, similar to the A56 virus, the G9H44Y mutant virus on HeLa cells had a cell fusion phenotype, indicating that G9H44Y-mediated membrane fusion was less prone to inhibition by A56/K2. Coimmunoprecipitation experiments demonstrated that the G9H44Y protein bound to A56/K2 at neutral pH, suggesting that the H44Y mutation did not eliminate the binding of G9 to A56/K2. Interestingly, upon acid treatment to inactivate A56/K2-mediated fusion inhibition, the G9H44Y mutant virus induced robust cell-cell fusion at pH 6, unlike the pH 4.7 required for control and revertant vaccinia viruses. Thus, A56/K2 fusion suppression mainly targets the G9 protein. Moreover, the G9H44Y mutant protein escapes A56/K2-mediated membrane fusion inhibition most likely because it mimics an acid-induced intermediate conformation more prone to membrane fusion.

    IMPORTANCE It remains unclear how the multiprotein entry fusion complex of vaccinia virus mediates membrane fusion. Moreover, vaccinia virus contains fusion suppressor proteins to prevent the aberrant activation of this multiprotein complex. Here, we used experimental evolution to identify adaptive mutant viruses that overcome membrane fusion inhibition mediated by the A56/K2 protein complex. We show that the H44Y mutation of the G9 protein is sufficient to overcome A56/K2-mediated membrane fusion inhibition. Treatment of virus-infected cells at different pHs indicated that the H44Y mutation lowers the threshold of fusion inhibition by A56/K2. Our study provides evidence that A56/K2 inhibits the viral fusion complex via the latter’s G9 subcomponent. Although the G9H44Y mutant protein still binds to A56/K2 at neutral pH, it is less dependent on low pH for fusion activation, implying that it may adopt a subtle conformational change that mimics a structural intermediate induced by low pH.




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    Opinion: We need a global movement to transform ocean science for a better world [Sustainability Science]

    The ocean is our planet’s largest life-support system. It stabilizes climate; stores carbon; produces oxygen; nurtures biodiversity; directly supports human well-being through food, mineral, and energy resources; and provides cultural and recreational services. The value of the ocean economy speaks to its importance: The Organization for Economic Cooperation and Development...




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    Asking young children to &#x201C;do science&#x201D; instead of &#x201C;be scientists&#x201D; increases science engagement in a randomized field experiment [Psychological and Cognitive Sciences]

    Subtle features of common language can imply to young children that scientists are a special and distinct kind of person—a way of thinking that can interfere with the development of children’s own engagement with science. We conducted a large field experiment (involving 45 prekindergarten schools, 130 teachers, and over 1,100...




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    In utero MRI identifies consequences of early-gestation alcohol drinking on fetal brain development in rhesus macaques [Neuroscience]

    One factor that contributes to the high prevalence of fetal alcohol spectrum disorder (FASD) is binge-like consumption of alcohol before pregnancy awareness. It is known that treatments are more effective with early recognition of FASD. Recent advances in retrospective motion correction for the reconstruction of three-dimensional (3D) fetal brain MRI...




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    A minor population of macrophage-tropic HIV-1 variants is identified in recrudescing viremia following analytic treatment interruption [Microbiology]

    HIV-1 persists in cellular reservoirs that can reignite viremia if antiretroviral therapy (ART) is interrupted. Therefore, insight into the nature of those reservoirs may be revealed from the composition of recrudescing viremia following treatment cessation. A minor population of macrophage-tropic (M-tropic) viruses was identified in a library of recombinant viruses...




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    Development of a therapeutic anti-HtrA1 antibody and the identification of DKK3 as a pharmacodynamic biomarker in geographic atrophy [Medical Sciences]

    Genetic polymorphisms in the region of the trimeric serine hydrolase high-temperature requirement 1 (HTRA1) are associated with increased risk of age-related macular degeneration (AMD) and disease progression, but the precise biological function of HtrA1 in the eye and its contribution to disease etiologies remain undefined. In this study, we have...




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    A genome-wide association study identifies key modulators of complement factor H binding to malondialdehyde-epitopes [Immunology and Inflammation]

    Genetic variants within complement factor H (CFH), a major alternative complement pathway regulator, are associated with the development of age-related macular degeneration (AMD) and other complementopathies. This is explained with the reduced binding of CFH or its splice variant factor H-like protein 1 (FHL-1) to self-ligands or altered self-ligands (e.g.,...




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    Starvation and antimetabolic therapy promote cytokine release and recruitment of immune cells [Immunology and Inflammation]

    Cellular starvation is typically a consequence of tissue injury that disrupts the local blood supply but can also occur where cell populations outgrow the local vasculature, as observed in solid tumors. Cells react to nutrient deprivation by adapting their metabolism, or, if starvation is prolonged, it can result in cell...




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    Landscape analysis of ad&#x0237;acent gene rearrangements reveals BCL2L14-ETV6 gene fusions in more aggressive triple-negative breast cancer [Genetics]

    Triple-negative breast cancer (TNBC) accounts for 10 to 20% of breast cancer, with chemotherapy as its mainstay of treatment due to lack of well-defined targets, and recent genomic sequencing studies have revealed a paucity of TNBC-specific mutations. Recurrent gene fusions comprise a class of viable genetic targets in solid tumors;...




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    Ammonia emission abatement does not fully control reduced forms of nitrogen deposition [Environmental Sciences]

    Human activities and population growth have increased the natural burden of reactive nitrogen (N) in the environment. Excessive N deposition on Earth’s surface leads to adverse feedbacks on ecosystems and humans. Similar to that of air pollution, emission control is recognized as an efficient means to control acid deposition. Control...




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    Improved surrogates in inertial confinement fusion with manifold and cycle consistencies [Computer Sciences]

    Neural networks have become the method of choice in surrogate modeling because of their ability to characterize arbitrary, high-dimensional functions in a data-driven fashion. This paper advocates for the training of surrogates that are 1) consistent with the physical manifold, resulting in physically meaningful predictions, and 2) cyclically consistent with...




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    Metal ions confinement defines the architecture of G-quartet, G-quadruplex fibrils and their assembly into nematic tactoids [Chemistry]

    G-quadruplex, assembled from a square array of guanine (G) molecules, is an important structure with crucial biological roles in vivo but also a versatile template for ordered functional materials. Although the understanding of G-quadruplex structures is the focus of numerous studies, little is known regarding the control of G-quartet stacking...




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    Direct kinetic measurements and theoretical predictions of an isoprene-derived Criegee intermediate [Chemistry]

    Isoprene has the highest emission into Earth’s atmosphere of any nonmethane hydrocarbon. Atmospheric processing of alkenes, including isoprene, via ozonolysis leads to the formation of zwitterionic reactive intermediates, known as Criegee intermediates (CIs). Direct studies have revealed that reactions involving simple CIs can significantly impact the tropospheric oxidizing capacity, enhance...




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    MTV proteins unveil ER- and microtubule-associated compartments in the plant vacuolar trafficking pathway [Cell Biology]

    The factors and mechanisms involved in vacuolar transport in plants, and in particular those directing vesicles to their target endomembrane compartment, remain largely unknown. To identify components of the vacuolar trafficking machinery, we searched for Arabidopsis modified transport to the vacuole (mtv) mutants that abnormally secrete the synthetic vacuolar cargo...




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    Optimizing Rhizobium-legume symbioses by simultaneous measurement of rhizobial competitiveness and N2 fixation in nodules [Agricultural Sciences]

    Legumes tend to be nodulated by competitive rhizobia that do not maximize nitrogen (N2) fixation, resulting in suboptimal yields. Rhizobial nodulation competitiveness and effectiveness at N2 fixation are independent traits, making their measurement extremely time-consuming with low experimental throughput. To transform the experimental assessment of rhizobial competitiveness and effectiveness, we...




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    Metrics that matter for assessing the ocean biological carbon pump [Environmental Sciences]

    The biological carbon pump (BCP) comprises wide-ranging processes that set carbon supply, consumption, and storage in the oceans’ interior. It is becoming increasingly evident that small changes in the efficiency of the BCP can significantly alter ocean carbon sequestration and, thus, atmospheric CO2 and climate, as well as the functioning...




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    PCARE and WASF3 regulate ciliary F-actin assembly that is required for the initiation of photoreceptor outer segment disk formation [Genetics]

    The outer segments (OS) of rod and cone photoreceptor cells are specialized sensory cilia that contain hundreds of opsin-loaded stacked membrane disks that enable phototransduction. The biogenesis of these disks is initiated at the OS base, but the driving force has been debated. Here, we studied the function of the...




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    Reply to Schild et al.: Antisocial personality moderates the causal influence of costly punishment on trust and trustworthiness [Social Sciences]

    A growing literature at the intersection of personality psychology and behavioral economics investigates the interplay between personality and decision making in social dilemmas (1, 2). Engelmann et al. (3) extend prior research in this area by investigating the role of antisocial personality in the context of a trust game with...




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    NRF3-POMP-20S Proteasome Assembly Axis Promotes Cancer Development via Ubiquitin-Independent Proteolysis of p53 and Retinoblastoma Protein [Research Article]

    Proteasomes are essential protease complexes that maintain cellular homeostasis, and aberrant proteasomal activity supports cancer development. The regulatory mechanisms and biological function of the ubiquitin-26S proteasome have been studied extensively, while those of the ubiquitin-independent 20S proteasome system remain obscure. Here, we show that the cap ’n’ collar (CNC) family transcription factor NRF3 specifically enhances 20S proteasome assembly in cancer cells and that 20S proteasomes contribute to colorectal cancer development through ubiquitin-independent proteolysis of the tumor suppressor p53 and retinoblastoma (Rb) proteins. The NRF3 gene is highly expressed in many cancer tissues and cell lines and is important for cancer cell growth. In cancer cells, NRF3 upregulates the assembly of the 20S proteasome by directly inducing the gene expression of the 20S proteasome maturation protein POMP. Interestingly, NRF3 knockdown not only increases p53 and Rb protein levels but also increases p53 activities for tumor suppression, including cell cycle arrest and induction of apoptosis. Furthermore, protein stability and cell viability assays using two distinct proteasome inhibitor anticancer drugs, the 20S proteasome inhibitor bortezomib and the ubiquitin-activating enzyme E1 inhibitor TAK-243, show that the upregulation of the NRF3-POMP axis leads to ubiquitin-independent proteolysis of p53 and Rb and to impaired sensitivity to bortezomib but not TAK-243. More importantly, the NRF3-POMP axis supports tumorigenesis and metastasis, with higher NRF3/POMP expression levels correlating with poor prognoses in patients with colorectal or rectal adenocarcinoma. These results suggest that the NRF3-POMP-20S proteasome assembly axis is significant for cancer development via ubiquitin-independent proteolysis of tumor suppressor proteins.




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    Requirement of the Cep57-Cep63 Interaction for Proper Cep152 Recruitment and Centriole Duplication [Research Article]

    Cep57 has been characterized as a component of a pericentriolar complex containing Cep63 and Cep152. Interestingly, Cep63 and Cep152 self-assemble into a pericentriolar cylindrical architecture, and this event is critical for the orderly recruitment of Plk4, a key regulator of centriole duplication. However, the way in which Cep57 interacts with the Cep63-Cep152 complex and contributes to the structure and function of Cep63-Cep152 self-assembly remains unknown. We demonstrate that Cep57 interacts with Cep63 through N-terminal motifs and associates with Cep152 via Cep63. Three-dimensional structured illumination microscopy (3D-SIM) analyses suggested that the Cep57-Cep63-Cep152 complex is concentrically arranged around a centriole in a Cep57-in and Cep152-out manner. Cep57 mutant cells defective in Cep63 binding exhibited improper Cep63 and Cep152 localization and impaired Sas6 recruitment for procentriole assembly, proving the significance of the Cep57-Cep63 interaction. Intriguingly, Cep63 fused to a microtubule (MT)-binding domain of Cep57 functioned in concert with Cep152 to assemble around stabilized MTs in vitro. Thus, Cep57 plays a key role in architecting the Cep63-Cep152 assembly around centriolar MTs and promoting centriole biogenesis. This study may offer a platform to investigate how the organization and function of the pericentriolar architecture are altered by disease-associated mutations found in the Cep57-Cep63-Cep152 complex.




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    Correction for Dietz et al., "2019 Novel Coronavirus (COVID-19) Pandemic: Built Environment Considerations To Reduce Transmission"




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    Family Medicine Certification Longitudinal Assessment after One Year