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Continuously evolving influenza viruses cause seasonal epidemics and pose global pandemic threats. Although viral neuraminidase (NA) is an effective drug and vaccine target, our understanding of the NA antigenic landscape still remains incomplete. Here, we describe NA-specific human antibodies that target the underside of the NA globular head domain, inhibit viral propagation of a wide range of human H3N2, swine-origin variant H3N2, and H2N2 viruses, and confer both pre- and post-exposure protection against lethal H3N2 infection in mice. Cryo-EM structures of two such antibodies in complex with NA reveal non-overlapping epitopes covering the underside of the NA head. These sites are highly conserved among N2 NAs yet inaccessible unless the NA head tilts or dissociates. Our findings help guide the development of effective countermeasures against ever-changing influenza viruses by identifying hidden conserved sites of vulnerability on the NA underside.
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Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Humanos , Animais , Camundongos , Suínos , Proteínas Virais/genética , Neuraminidase , Vírus da Influenza A Subtipo H3N2 , Anticorpos Monoclonais , Anticorpos AntiviraisRESUMO
In the version of this article initially published, the labels (50 Å) above the scale bars in Fig. 1b were incorrect. The correct size is 50 nm. The error has been corrected in the HTML and PDF versions of the article.
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The present vaccine against influenza virus has the inevitable risk of antigenic discordance between the vaccine and the circulating strains, which diminishes vaccine efficacy. This necessitates new approaches that provide broader protection against influenza. Here we designed a vaccine using the hypervariable receptor-binding domain (RBD) of viral hemagglutinin displayed on a nanoparticle (np) able to elicit antibody responses that neutralize H1N1 influenza viruses spanning over 90 years. Co-display of RBDs from multiple strains across time, so that the adjacent RBDs are heterotypic, provides an avidity advantage to cross-reactive B cells. Immunization with the mosaic RBD-np elicited broader antibody responses than those induced by an admixture of nanoparticles encompassing the same set of RBDs as separate homotypic arrays. Furthermore, we identified a broadly neutralizing monoclonal antibody in a mouse immunized with mosaic RBD-np. The mosaic antigen array signifies a unique approach that subverts monotypic immunodominance and allows otherwise subdominant cross-reactive B cell responses to emerge.
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Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Nanopartículas/química , Infecções por Orthomyxoviridae/imunologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/virologia , Reações Cruzadas/efeitos dos fármacos , Reações Cruzadas/imunologia , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Imunização , Vírus da Influenza A Subtipo H1N1/metabolismo , Vírus da Influenza A Subtipo H1N1/fisiologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/química , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologiaRESUMO
Epstein-Barr virus (EBV) is nearly ubiquitous in adults. EBV causes infectious mononucleosis and is associated with B cell lymphomas, epithelial cell malignancies, and multiple sclerosis. The EBV gH/gL glycoprotein complex facilitates fusion of virus membrane with host cells and is a target of neutralizing antibodies. Here, we examined the sites of vulnerability for virus neutralization and fusion inhibition within EBV gH/gL. We developed a panel of human monoclonal antibodies (mAbs) that targeted five distinct antigenic sites on EBV gH/gL and prevented infection of epithelial and B cells. Structural analyses using X-ray crystallography and electron microscopy revealed multiple sites of vulnerability and defined the antigenic landscape of EBV gH/gL. One mAb provided near-complete protection against viremia and lymphoma in a humanized mouse EBV challenge model. Our findings provide structural and antigenic knowledge of the viral fusion machinery, yield a potential therapeutic antibody to prevent EBV disease, and emphasize gH/gL as a target for herpesvirus vaccines and therapeutics.
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Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Cricetinae , Camundongos , Animais , Humanos , Proteínas do Envelope Viral , Cricetulus , Glicoproteínas de Membrana , Células CHORESUMO
Current influenza vaccines predominantly induce immunity to the hypervariable hemagglutinin (HA) head, requiring frequent vaccine reformulation. Conversely, the immunosubdominant yet conserved HA stem harbors a supersite that is targeted by broadly neutralizing antibodies (bnAbs), representing a prime target for universal vaccines. Here, we showed that the co-immunization of two HA stem immunogens derived from group 1 and 2 influenza A viruses elicits cross-group protective immunity and neutralizing antibody responses in mice, ferrets, and nonhuman primates (NHPs). Immunized mice were protected from multiple group 1 and 2 viruses, and all animal models showed broad serum-neutralizing activity. A bnAb isolated from an immunized NHP broadly neutralized and protected against diverse viruses, including H5N1 and H7N9. Genetic and structural analyses revealed strong homology between macaque and human bnAbs, illustrating common biophysical constraints for acquiring cross-group specificity. Vaccine elicitation of stem-directed cross-group-protective immunity represents a step toward the development of broadly protective influenza vaccines.
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Virus da Influenza A Subtipo H5N1 , Subtipo H7N9 do Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Camundongos , Humanos , Hemaglutininas , Anticorpos Amplamente Neutralizantes , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Anticorpos Antivirais , Furões , Anticorpos Neutralizantes , ImunizaçãoRESUMO
Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions1,2. To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores3. The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms4,5.
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Microbiologia do Ar , Biodiversidade , DNA Fúngico , Fungos , Estações do Ano , Análise Espaço-Temporal , DNA Fúngico/análise , DNA Fúngico/genética , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Micorrizas/genética , Micorrizas/classificação , Micorrizas/isolamento & purificação , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/isolamento & purificação , Temperatura , Clima Tropical , Mapeamento GeográficoRESUMO
Nipah virus (NiV) and Hendra virus (HeV) are pathogenic paramyxoviruses that cause mild-to-severe disease in humans. As members of the Henipavirus genus, NiV and HeV use an attachment (G) glycoprotein and a class I fusion (F) glycoprotein to invade host cells. The F protein rearranges from a metastable prefusion form to an extended postfusion form to facilitate host cell entry. Prefusion NiV F elicits higher neutralizing antibody titers than postfusion NiV F, indicating that stabilization of prefusion F may aid vaccine development. A combination of amino acid substitutions (L104C/I114C, L172F, and S191P) is known to stabilize NiV F in its prefusion conformation, although the extent to which substitutions transfer to other henipavirus F proteins is not known. Here, we perform biophysical and structural studies to investigate the mechanism of prefusion stabilization in F proteins from three henipaviruses: NiV, HeV, and Langya virus (LayV). Three known stabilizing substitutions from NiV F transfer to HeV F and exert similar structural and functional effects. One engineered disulfide bond, located near the fusion peptide, is sufficient to stabilize the prefusion conformations of both HeV F and LayV F. Although LayV F shares low overall sequence identity with NiV F and HeV F, the region around the fusion peptide exhibits high sequence conservation across all henipaviruses. Our findings indicate that substitutions targeting this site of conformational change might be applicable to prefusion stabilization of other henipavirus F proteins and support the use of NiV as a prototypical pathogen for henipavirus vaccine antigen design.IMPORTANCEPathogenic henipaviruses such as Nipah virus (NiV) and Hendra virus (HeV) cause respiratory symptoms, with severe cases resulting in encephalitis, seizures, and coma. The work described here shows that the NiV and HeV fusion (F) proteins share common structural features with the F protein from an emerging henipavirus, Langya virus (LayV). Sequence alignment alone was sufficient to predict which known prefusion-stabilizing amino acid substitutions from NiV F would stabilize the prefusion conformations of HeV F and LayV F. This work also reveals an unexpected oligomeric interface shared by prefusion HeV F and NiV F. Together, these advances lay a foundation for future antigen design targeting henipavirus F proteins. In this way, Nipah virus can serve as a prototypical pathogen for the development of protective vaccines and monoclonal antibodies to prepare for potential henipavirus outbreaks.
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Vírus Hendra , Infecções por Henipavirus , Henipavirus , Vírus Nipah , Proteínas Virais , Humanos , Glicoproteínas/metabolismo , Vírus Hendra/fisiologia , Henipavirus/fisiologia , Vírus Nipah/genética , Vírus Nipah/metabolismo , Peptídeos/metabolismo , Proteínas Virais de Fusão , Proteínas Virais/metabolismoRESUMO
In response to stresses, cells often halt normal cellular processes, yet stress-specific pathways must bypass such inhibition to generate effective responses. We investigated how cells redistribute global transcriptional activity in response to DNA damage. We show that an oscillatory increase of p53 levels in response to double-strand breaks drives a counter-oscillatory decrease of MYC levels. Using RNA sequencing (RNA-seq) of newly synthesized transcripts, we found that p53-mediated reduction of MYC suppressed general transcription, with the most highly expressed transcripts reduced to a greater extent. In contrast, upregulation of p53 targets was relatively unaffected by MYC suppression. Reducing MYC during the DNA damage response was important for cell-fate regulation, as counteracting MYC repression reduced cell-cycle arrest and elevated apoptosis. Our study shows that global inhibition with specific activation of transcriptional pathways is important for the proper response to DNA damage; this mechanism may be a general principle used in many stress responses.
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Neoplasias da Mama/genética , Quebras de DNA de Cadeia Dupla , Proteínas Proto-Oncogênicas c-myc/genética , Transcrição Gênica , Transcriptoma , Proteína Supressora de Tumor p53/genética , Apoptose , Sítios de Ligação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sistemas CRISPR-Cas , Pontos de Checagem do Ciclo Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Células MCF-7 , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Proteína Supressora de Tumor p53/metabolismoRESUMO
BACKGROUND: Surgical site infections (SSIs) are a common complication in liver transplant (LT) recipients. Lack of pediatric prophylaxis guidelines results in variation in preventative antibiotic regimens. METHODS: We performed a retrospective observational study of LT recipients <18 years old using a merged data set that included data from the Pediatric Health Information System and the United Network for Organ Sharing between 2006 and 2017. The exposure was defined as the antibiotic(s) received within 24â hours of LT, with 6 categories, ranging from narrow (category 1: cefazolin), to broad). The primary outcome was presence or absence of SSI in the index admission. Mixed-effects logistic regression compared the effectiveness of each category in preventing SSI, relative to category 1. RESULTS: Of the 2586 LT, 284 (11%) met SSI criteria. The SSI rate was higher in the younger subcohort (16.2%) than in the older (8.6%), necessitating a stratified analysis. Antibiotics from category 5 were most commonly used. In the younger subcohort, the adjusted risk was increased in all categories compared with the reference, most notably in category 3 (odds ratio [OR], 2.58 [95% confidence interval: .69-9.59]) and category 6 (2.76 [.66-11.56]). In the older subcohort, estimated ORs were also increased for each category, most notably in category 4 (2.49 [95% confidence interval: .99-6.27]). None of the ORs suggested benefit from broader-spectrum prophylaxis. Our E-value assessment suggests that it's unlikely there is unmeasured confounding by indication to the degree necessary to revert ORs to protective. CONCLUSIONS: There was wide variation in antibiotic prophylaxis. Adjusted analyses did not reveal a protective benefit of broader-spectrum prophylaxis in either subcohort, suggesting that narrower regimens may be adequate.
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Antibacterianos , Antibioticoprofilaxia , Transplante de Fígado , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Estudos Retrospectivos , Transplante de Fígado/efeitos adversos , Masculino , Feminino , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Criança , Antibioticoprofilaxia/métodos , Pré-Escolar , Adolescente , Lactente , Transplantados , Assistência Perioperatória/métodosRESUMO
Pediatric-specific safety data are required during development of pharmaceutical agents. Retrospective studies can leverage real-world data to assess safety and effectiveness in children where prospective, controlled studies are not feasible. A retrospective cohort study combined data from Pediatric Health Information Systems (PHIS) and medical records to evaluate the safety and effectiveness of piperacillin/tazobactam (P/T) in pediatric patients with hospital-acquired pneumonia (HAP). After identifying 407 patients diagnosed with HAP receiving P/T (n=140) or Comparator (n=267) HAP-appropriate antibiotics between 2003-2016 across seven pediatric institutions, we evaluated comparative risk of a serious adverse event (SAE). Clinical improvement 14 days after therapy initiation was studied as a secondary outcome. Incidence rate ratios (IRRs) were calculated to compare between exposure groups using inverse probability-weighted Poisson regression models. The unadjusted and adjusted IRRs with 95% CIs for SAEs were 1.26(0.66-2.39) and 1.24(0.65-2.35). The unadjusted and adjusted ORs with 95% CIs for clinical improvement were 1.14(0.56-2.34) and 1.50(0.67-3.38). Point estimates from this retrospective analysis suggest similar safety and clinical effectiveness of P/T and comparator antibiotics for treating HAP. However, due to wide CIs, actual between-group differences cannot be excluded. Existing real-world data can be utilized to inform pediatric-specific safety and effectiveness of medications used in off-label settings.
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BACKGROUND: Pediatric acute myeloid leukemia (AML) chemotherapy increases the risk of life-threatening complications, including septic shock (SS). An area-based measure of social determinants of health, the social disorganization index (SDI), was hypothesized to be associated with SS and SS-associated death (SS-death). METHODS: Children treated for de novo AML on two Children's Oncology Group trials at institutions contributing to the Pediatric Health Information System (PHIS) database were included. The SDI was calculated via residential zip code data from the US Census Bureau. SS was identified via PHIS resource utilization codes. SS-death was defined as death within 2 weeks of an antecedent SS event. Patients were followed from 7 days after the start of chemotherapy until the first of end of front-line therapy, death, relapse, or removal from study. Multivariable-adjusted Cox regressions estimated hazard ratios (HRs) comparing time to first SS by SDI group. RESULTS: The assembled cohort included 700 patients, with 207 (29.6%) sustaining at least one SS event. There were 233 (33%) in the SDI-5 group (highest disorganization). Adjusted time to incident SS did not statistically significantly differ by SDI (reference, SDI-1; SDI-2: HR, 0.84 [95% confidence interval (CI), 0.51-1.41]; SDI-3: HR, 0.70 [95% CI, 0.42-1.16]; SDI-4: HR, 0.97 [95% CI, 0.61-1.53]; SDI-5: HR, 0.72 [95% CI, 0.45-1.14]). Nine patients (4.4%) with SS experienced SS-death; seven of these patients (78%) were in SDI-4 or SDI-5. CONCLUSIONS: In a large, nationally representative cohort of trial-enrolled pediatric patients with AML, there was no significant association between the SDI and time to SS.
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Leucemia Mieloide Aguda , Choque Séptico , Criança , Humanos , Choque Séptico/epidemiologia , Choque Séptico/complicações , Anomia (Social) , Leucemia Mieloide Aguda/terapia , Modelos de Riscos Proporcionais , RecidivaRESUMO
The more insects there are, the more food there is for insectivores and the higher the likelihood for insect-associated ecosystem services. Yet, we lack insights into the drivers of insect biomass over space and seasons, for both tropical and temperate zones. We used 245 Malaise traps, managed by 191 volunteers and park guards, to characterize year-round flying insect biomass in a temperate (Sweden) and a tropical (Madagascar) country. Surprisingly, we found that local insect biomass was similar across zones. In Sweden, local insect biomass increased with accumulated heat and varied across habitats, while biomass in Madagascar was unrelated to the environmental predictors measured. Drivers behind seasonality partly converged: In both countries, the seasonality of insect biomass differed between warmer and colder sites, and wetter and drier sites. In Sweden, short-term deviations from expected season-specific biomass were explained by week-to-week fluctuations in accumulated heat, rainfall and soil moisture, whereas in Madagascar, weeks with higher soil moisture had higher insect biomass. Overall, our study identifies key drivers of the seasonal distribution of flying insect biomass in a temperate and a tropical climate. This knowledge is key to understanding the spatial and seasonal availability of insects-as well as predicting future scenarios of insect biomass change.
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Biomassa , Estações do Ano , Temperatura , Clima Tropical , Animais , Suécia , Madagáscar , Insetos/fisiologia , Água , EcossistemaRESUMO
Evolutionary innovations underlie the rise of diversity and complexity-the 2 long-term trends in the history of life. How does natural selection redesign multiple interacting parts to achieve a new emergent function? We investigated the evolution of a biomechanical innovation, the latch-spring mechanism of trap-jaw ants, to address 2 outstanding evolutionary problems: how form and function change in a system during the evolution of new complex traits, and whether such innovations and the diversity they beget are repeatable in time and space. Using a new phylogenetic reconstruction of 470 species, and X-ray microtomography and high-speed videography of representative taxa, we found the trap-jaw mechanism evolved independently 7 to 10 times in a single ant genus (Strumigenys), resulting in the repeated evolution of diverse forms on different continents. The trap mechanism facilitates a 6 to 7 order of magnitude greater mandible acceleration relative to simpler ancestors, currently the fastest recorded acceleration of a resettable animal movement. We found that most morphological diversification occurred after evolution of latch-spring mechanisms, which evolved via minor realignments of mouthpart structures. This finding, whereby incremental changes in form lead to a change of function, followed by large morphological reorganization around the new function, provides a model for understanding the evolution of complex biomechanical traits, as well as insights into why such innovations often happen repeatedly.
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Adaptação Biológica/fisiologia , Formigas/fisiologia , Mandíbula/anatomia & histologia , Animais , Formigas/metabolismo , Evolução Biológica , Fenômenos Biomecânicos/fisiologia , Evolução Molecular , Mandíbula/fisiologia , Movimento , Filogenia , Relação Estrutura-Atividade , Microtomografia por Raio-X/métodosRESUMO
Case identification in administrative databases is challenging as diagnosis codes alone are not adequate for case ascertainment. We utilized machine learning (ML) to efficiently identify pediatric patients with newly diagnosed acute lymphoblastic leukemia. We tested nine ML models and validated the best model internally and externally. The optimal model had 97% positive predictive value (PPV) and 99% sensitivity in internal validation; 94% PPV and 82% sensitivity in external validation. Our ML model identified a large cohort of 21,044 patients, demonstrating an efficient approach for cohort assembly and enhancing the usability of administrative data.
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Algoritmos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Valor Preditivo dos Testes , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Aprendizado de Máquina , Bases de Dados FactuaisRESUMO
BACKGROUND: The primary objective was to measure the proportion of episodes where care delivery was inconsistent with selected recommendations of a clinical practice guideline (CPG) on fever and neutropenia (FN) management. The influence of site size on CPG-inconsistent care delivery, and association between patient outcomes and CPG-inconsistent care were described. METHODS: This retrospective, multicenter study included patients less than 21 years old with cancer who were at high risk of poor FN outcomes and were previously enrolled to a Children's Oncology Group (COG) study at participating National Cancer Institute Community Oncology Research Program (NCORP) institutions from January 2014 through December 2015. Patients were randomly selected for chart review by participating sites from a COG-generated list. Care delivered in each episode was adjudicated (CPG-consistent or CPG-inconsistent) against each of five selected recommendations. RESULTS: A total of 107 patients from 22 sites, representing 157 FN episodes, were included. The most common CPG-inconsistent care delivered was omission of pulmonary computerized tomography in patients with persistent FN (60.3%). Of 74 episodes where assessment of four (episodes without persistent FN) or five (episodes with persistent FN) recommendations was possible, CPG-inconsistent care was delivered with respect to at least one recommendation in 63 (85%) episodes. Site size was not associated with CPG-inconsistent care delivery. No statistically significant association between CPG-inconsistent care and fever recurrence was observed. CONCLUSIONS: In this cohort of pediatric patients at high risk of poor FN outcomes, CPG-inconsistent care was common. Opportunities to optimize resource stewardship by boosting supportive care CPG implementation are highlighted.
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Febre de Causa Desconhecida , Neoplasias , Neutropenia , Criança , Humanos , Adulto Jovem , Oncologia , Neoplasias/complicações , Neoplasias/terapia , Neutropenia/terapia , Neutropenia/complicações , Estudos Retrospectivos , AdolescenteRESUMO
Children with sickle cell disease (SCD) are at risk of complications from viral infections, including SARS-CoV-2. We present the clinical characteristics and outcomes of pediatric patients with SCD from the Pediatric COVID-19 United States Registry who developed acute COVID-19 due to SARS-CoV-2 infection (n = 259) or multisystem inflammatory syndrome in children (MIS-C; n = 4). Nearly half of hospitalized children with SCD and SARS-CoV-2 infection required supplemental oxygen, though children with SCD had fewer intensive care (ICU) admissions compared to the general pediatric and immunocompromised populations. All registry patients with both SCD and MIS-C required ICU admission. Children with SCD are at risk of severe disease with SARS-CoV-2 infection, highlighting the importance of vaccination in this vulnerable population.
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Anemia Falciforme , COVID-19 , COVID-19/complicações , Sistema de Registros , SARS-CoV-2 , Humanos , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Anemia Falciforme/terapia , COVID-19/epidemiologia , Criança , Feminino , Masculino , Adolescente , Estados Unidos/epidemiologia , Pré-Escolar , Lactente , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Hospitalização/estatística & dados numéricosRESUMO
BACKGROUND: Cytomegalovirus (CMV) commonly reactivates after allogeneic hematopoietic cell transplant (HCT), potentially leading to CMV disease and significant morbidity and mortality. To reduce morbidity and mortality, many centers conduct weekly CMV blood polymerase chain reaction (PCR) surveillance testing with subsequent initiation of antiviral therapy upon CMV DNAemia detection. However, the impact of CMV DNAemia on subsequent hospitalization risk has not been assessed using models accounting for the time-varying nature of the exposure, outcome, and confounders. METHODS: All allogeneic HCTs at the Children's Hospital of Philadelphia from January 2004-April 2017 were considered for inclusion. Patients were monitored with CMV surveillance via PCR testing for up to 105 days after HCT receipt. We estimated the association between CMV DNAemia and rate of hospitalization using marginal structural models (MSM). RESULTS: There were 343 allogeneic HCT episodes in 330 with CMV surveillance; median age was 9.0 (range: 0.1-26.2) and 46.5% were female. And 24.1% of HCT patients had at least one positive CMV blood PCR during the follow-up period. Median time to CMV DNAemia detection was 19 days (range: 4-97). The MSM estimated the incidence rate ratios for an association of CMV DNAemia with hospitalization to be 1.24, (95% confidence interval: 1.04-1.47). CONCLUSIONS: CMV DNAemia was associated with an increased hospitalization in the post-HCT period. The MSM accounted for time-varying nature of the outcome, exposure and confounders. The findings support prevention of CMV DNAemia in this population. We recommend further investigation into the effectiveness and safety of prophylaxis versus pre-emptive CMV prevention approaches.
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Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Criança , Humanos , Feminino , Masculino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante Homólogo/efeitos adversos , DNA Viral , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus , Antivirais/uso terapêutico , Estudos RetrospectivosRESUMO
BACKGROUND: Pediatric allogeneic hematopoietic cell transplant (allo-HCT) recipients are at risk for morbidity and mortality from human adenovirus (HAdV). HAdV can be detected in an asymptomatic state, referred to as infection or with signs or symptoms of illness, referred to as disease. Standardized case definitions are needed to distinguish infection from disease and allow for consistent reporting in both observational cohort studies and therapeutic clinical trials. METHODS: A working group of experts in virology, transplant infectious disease, and HCT was assembled to develop HAdV infection and disease definitions with the degree of certainty (i.e., possible, probable, and proven). Definitions were further refined through an iterative process and independently applied by two central review committees (CRCs) to 20 pediatric allo-HCT recipients with at least one HAdV-positive PCR. RESULTS: Initial HAdV infection and disease definitions were developed and updated through an iterative process after reviewing clinical and virological details for 81 subjects with at least one positive HAdV PCR detected in a clinical specimen. Independent application of final definitions to 20 HAdV positive allo-HCT recipients by two CRCs yielded similar number of HAdV infection or disease events but with variation of degree of certainty for some events. CONCLUSIONS: Application of definitions by a CRC for a study of HAdV infection and disease is feasible and can provide consistency in the assignment of outcomes. Definitions need further refinement to improve reproducibility and to provide guidance on determining clinical improvement or worsening after initial diagnosis of HAdV infection or disease.
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Infecções por Adenovirus Humanos , Adenovírus Humanos , Transplante de Células-Tronco Hematopoéticas , Criança , Humanos , Infecções por Adenovirus Humanos/diagnóstico , Reprodutibilidade dos Testes , Transplante Homólogo , Estudos de CoortesRESUMO
BACKGROUND: Treatment with corticosteroids is common for patients with idiopathic and multiple sclerosis-associated optic neuritis (I/MS-ON). Yet, the Optic Neuritis Treatment Trial and meta-analyses confirm that few patients benefit and that visual benefit is of questionable clinical significance, short-lived, and comes with potential harms. The purpose of this study was to uncover the breadth of factors that underlie clinicians' treatment decisions and determine how these factors may influence corticosteroid use for I/MS-ON. METHODS: We performed semistructured, one-on-one, qualitative interviews with neurologists, neuro-ophthalmologists, and emergency department clinicians at 15 academic and private practices across the United States. The interview guide used the Theoretical Domain Framework and a vignette to explore numerous factors that might influence decision making for definite I/MS-ON. We analyzed transcripts using inductive thematic analysis to generate themes. RESULTS: A total of 22 clinicians were interviewed before thematic saturation was reached: 8 neuro-ophthalmologists, 8 neurologists, and 6 emergency medicine (EM) clinicians (2 physician assistants, 4 physicians). All neuro-ophthalmologists and nearly all neurologists (7 of 8) were aware of risks/benefits of corticosteroid treatment for I/MS-ON. However, neuro-ophthalmologists varied in their corticosteroid treatment recommendation (n = 3 recommended treatment, n = 2 recommended observation, n = 3 recommended shared decision making), whereas all neurologists recommended corticosteroids, indicating that knowledge of corticosteroid risk/benefit alone does not drive decision making. EM clinicians were not aware of risk/benefits of corticosteroid treatment for I/MS-ON and relied on the treatment recommendations of neurologists. Clinicians recommending corticosteroids held personal beliefs that corticosteroids benefit those with worse vision loss, relieve pain, allow earlier return to work, or have easily mitigated side effects. They also perceived that prescribing steroid was the principal method of "doing something," which fit a key provider role. Clinicians who did not recommend corticosteroids or were neutral perceived the risks as nontrivial, considered discussing treatment trade-offs as "doing something" and incorporated patient preferences. CONCLUSIONS: Knowledge of risk/benefits of corticosteroids are necessary but not sufficient for evidence-based I/MS-ON practice. Variation in how clinicians treat patients with acute I/MS-ON is influenced largely by psychosocial factors, such as beliefs about corticosteroid risk/benefit trade-offs and the role of the clinician to provide treatment. Interventions to support evidence-based decision making for I/MS-ON treatment will need to provide risk/benefit information to support clinicians with varying levels of expertise, incorporate patient preference, and normalize the option to observe.
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Termites are major decomposers in terrestrial ecosystems and the second most diverse lineage of social insects. The Kalotermitidae form the second-largest termite family and are distributed across tropical and subtropical ecosystems, where they typically live in small colonies confined to single wood items inhabited by individuals with no foraging abilities. How the Kalotermitidae have acquired their global distribution patterns remains unresolved. Similarly, it is unclear whether foraging is ancestral to Kalotermitidae or was secondarily acquired in a few species. These questions can be addressed in a phylogenetic framework. We inferred time-calibrated phylogenetic trees of Kalotermitidae using mitochondrial genomes of â¼120 species, about 27% of kalotermitid diversity, including representatives of 21 of the 23 kalotermitid genera. Our mitochondrial genome phylogenetic trees were corroborated by phylogenies inferred from nuclear ultraconserved elements derived from a subset of 28 species. We found that extant kalotermitids shared a common ancestor 84â Ma (75-93â Ma 95% highest posterior density), indicating that a few disjunctions among early-diverging kalotermitid lineages may predate Gondwana breakup. However, most of the â¼40 disjunctions among biogeographic realms were dated at <50â Ma, indicating that transoceanic dispersals, and more recently human-mediated dispersals, have been the major drivers of the global distribution of Kalotermitidae. Our phylogeny also revealed that the capacity to forage is often found in early-diverging kalotermitid lineages, implying the ancestors of Kalotermitidae were able to forage among multiple wood pieces. Our phylogenetic estimates provide a platform for critical taxonomic revision and future comparative analyses of Kalotermitidae.