bluuebunny/crossref_metadata_2025_split huggingface dataset:
#24: Death is Antibiotic-Microbiota Dependent in a Humanized Mouse Model of Late-Onset Neonatal Sepsis
Authors: Schwartz D , D’Souza A , Crofts T , Ning J , Shalon N , Robinson J , Henderson J , Warner B , Tarr P , Dantas G 
Published: March 2021

Abstract

Background
Premature infants receive antibiotics frequently for culture-negative sepsis, which diminishes gut microbial diversity and increases susceptibility to infections by antibiotic-resistant pathogens. Neonates with decreased gut microbiota diversity, termed dysbiotic, have dysregulated immune systems marked by increased concentrations of circulating activated T cells and decreased concentrations of circulating neutrophils and dendritic cells. We hypothesize that antibiotics (1) enrich for pathobionts within the gut, (2) promote a systemic, proinflammatory host response, and (3) cause death in an antibiotic specific manner in a gnotobiotic model of preterm gut microbiota development.

Methods
We colonized germ-free (GF) dams and sires with stools from preterm infants. Mouse pups acquire this neonatal microbiota, and at 10 days of life (DOL), we treat them with clinically relevant doses of antibiotics subcutaneously for 3 days. We use metagenomic shotgun sequencing of individual pup fecal samples longitudinally to ascertain phylogenetic composition, and use flow cytometry and multiplex cytokine arrays to determine the local and peripheral immune response.

Results
Using two representative microbiota from human neonates (hereafter referred to as microbiota A or B), we show that 94% of pups given microbiota A survive vs. 64% given microbiota B after meropenem/probenecid treatment (Figure 1; P &lt; 0.05; n = 18–28 mice in &gt; independent experiments). 40% of pups given microbiota A treated with ampicillin/gentamicin/probenecid survived (Figure 1; P &lt; 0.01 relative to meropenem/probenecid or probenecid). Klebsiella species dominated the gut microbiota of microbiota A-humanized pups who succumbed and were found in the lung, liver, and spleen of one animal at necropsy. Enterococci dominated the gut microbiota of microbiota B-humanized pups who died during treatment. Pups colonized with microbiota B had increased peripheral CD4+ T cells at sacrifice after treatment compared with microbiota A-humanized pups (61% vs. 44% of circulating T cells, P &lt; 0.0005).

Conclusions
Our model of preterm microbiota development and perturbation by antibiotics demonstrates potential bacterial translocation, proinflammatory immune response, and death dependent on the microbiota–antibiotic combination. Our transgenerational humanized-microbiota mouse model can be utilized to determine antibiotic by microbiota perturbation and examine risks of late-onset sepsis from antimicrobials.
#64: An odyssey Beyond the Capsule: Genetic Determinants of Pediatric Invasive Streptococcus pneumoniae Empyema
Authors: Pershing Nicole L , Kapusta Aurélie , Nielsen Shannon , Crandall Hillary , Korgenski E Kent , Byington Carrie L , Ampofo Krow , Blaschke Anne J 
Published: March 2021

Abstract

Background
Streptococcus pneumoniae is among the most common causes of invasive bacterial infections in children, including pneumonia, bacteremia, and meningitis. Over 90 different serotypes (ST) of pneumococcus exist, with enrichment of some ST within specific invasive phenotypes. Other than capsular genes, molecular determinants of particular invasive phenotypes remain largely unknown. Although vaccination targeting especially invasive ST capsular antigens has successfully decreased the incidence of invasive pneumococcal disease (IPD), new ST have emerged, suggesting methods to target other aspects of pneumococcal invasiveness are needed.

Methods
Pneumococcal isolates from IPD were collected from children presenting to Primary Children’s Hospital from 1996–2018. All viable isolates underwent next-generation sequencing (Illumina), quality control filtering for contamination and low coverage, de novo genome assembly with SPADES, and annotation with PROKKA. Clinical phenotypes were manually validated with physician chart review. Isolates were serotyped via Quelling and in silico using SeroBA. ROARY was used for pan-genome assembly, and SCOARY for microbial genome-wide association studies. RAxML was used for phylogenetic analysis.

Results
A total of 354 viable pneumococcal isolates were available for genomic analysis including a spectrum of invasive phenotypes: pneumonia (n = 138, of which 54 were complicated by empyema), CNS infection (n = 50), SSTI/bone infections (n = 42), and isolated bacteremia (n = 68). Thirteen samples were censored for poor coverage or genetic contamination. Invasive isolates spanned 37 capsular ST. The pneumococcal pan-genome comprised 6462 genes, of which only 23% were shared by at least 99% of samples. Phylogenetic relatedness resulted in clustering of some ST (e.g., ST1, ST3), whereas others (eg ST19A) were more broadly distributed. Empyema and meningitis phenotypes were distributed across the phylogenetic tree, but enriched in distinct clusters that crossed ST clusters. Genes involved in empyemagenic pneumococcal capsule production, and those implicated in sensing of preferred sugars or non-preferred sugar metabolism were statistically correlated with the empyema phenotype.

Conclusion
There is marked genetic diversity among invasive pneumococcal isolates, potentially contributing to the variability of disease phenotypes observed. Clustering of invasive phenotypes across ST suggests a genetic signature for invasive phenotypes other than capsule genes alone, further supported by enrichment of specific genes associated with alternative sugar metabolism in empyema isolates. Critical determinants of invasive phenotypes will inform future efforts at disease prevention and treatment.
#91: Human Antibodies Neutralize Enterovirus D68 and Protect Against Infection and Paralytic Disease
Authors: Vogt Matthew R , Kose Nurgun , Williamson Lauren E , Bochkov Yury A , Gern James E , Crowe James E 
Published: March 2021

Abstract

Background
Enterovirus D68 (EV-D68) causes worldwide outbreaks of human respiratory illness with spatiotemporally related outbreaks of acute flaccid myelitis (AFM). The major circulating clade of EV-D68 has changed since the largest ever recorded outbreak, which occurred in the United States in 2014. Numerous seroepidemiology studies show that essentially all adult humans have EV-D68-neutralizing antibodies in their serum, even in serum collected prior to large outbreaks. But some studies show a lack of neutralizing antibodies in pediatric populations. We sought to isolate human monoclonal antibodies (mAbs) from B cells in peripheral blood mononuclear cells (PBMCs) of immune subjects, induced by natural infection, to further understand human humoral immunity to EV-D68.

Methods
We obtained PBMCs from donors with known infection during 2014. We used EV-D68 virus isolates from this outbreak as antigen in an indirect ELISA to screen immortalized PBMCs for antigen-specificity, then fused B cells with myeloma cells to create hybridomas.

Results
We isolated &gt;60 naturally occurring anti-EV-D68 human mAbs. These mAbs exhibit diverse binding affinities when compared across clades of recent EV-D68 isolates. Many mAbs neutralize EV-D68 quite potently in vitro, with [ng/mL] half-maximal effective concentrations. Some mAbs like EV68-228 neutralize diverse clades, whereas others are highly clade-specific. Binding of antibodies to at least three, but likely more, major antigenic sites on the virus leads to neutralization. When given as either prophylaxis before or treatment after EV-D68 inoculation, mAb EV68-228 protects mice from both respiratory and neurologic disease, whereas equivalent doses of polyclonal human immunoglobulin protect only partially.

Conclusions
We observed a qualitative difference among antibodies isolated from patients who had a history of natural infection. These differences could contribute to certain individuals being susceptible to respiratory disease and AFM. These studies of humoral immunity are especially important for a disease with nearly universal apparent seroprotection, in which the virus somehow persistently causes outbreaks across the world. Furthermore, no licensed vaccines or treatments exist for EV-D68. These mAbs have therapeutic benefit in vivo and show promise for the prevention and/or treatment of EV-D68-related diseases in humans. We are pursuing the use of mAb EV68-228 in humans with partners in industry and government agencies.
#80: Developing and Implementing an Infectious Diseases Training Seminar for Global Healthcare Providers for Children with Cancer
Authors: Caniza M , Homsi M , Rodriguez-Galindo C 
Published: March 2021

Abstract

Background
Well-trained and dedicated personnel for infection care and prevention is essential for optimal care in pediatric oncology centers. Feedback from global collaborators consistently identifies education and training as a priority. We collaboratively designed and implemented a blended methodology training course focused on four essential themes: infectious complications in pediatric cancer; quality in infection care; quality in infection prevention; and, sustainability, research, and dissemination.

Methods
Using our team’s subject matter expertise and experience developing training materials, we designed the training seminar comprising two components: (1) an 8-week distance-learning segment delivered online through our free, education website (www.Cure4Kids.org) which focuses on building foundational knowledge in the identified essential themes of infection diseases; and, (2) a 2-week residential training seminar delivered face-to-face at St. Jude Children’s Hospital, which consolidates training through interactive lectures, workshops, clinical and research area tours, and research project presentations.

Results
The initial launch in 2017 trained 22 healthcare providers from 17 healthcare institutions in 10 countries. Knowledge gain from pretest to posttest for each module was significant (P &lt; 0.001). Satisfaction with course delivery was high; most participants (93–100%) found each module’s content relevant to their daily practice. For residential training, participants rated each day as either good (median: 10%; range: 5–25%) or outstanding (median: 90%; range: 75–95%). Individual research projects developed by course participants focused on bloodstream infections, febrile neutropenia, multi-drug-resistant organisms, fungal infections, hand hygiene, antibiotic prophylaxis, and infection prevention. After the course conclusion, nearly half (n = 9) implemented their project idea in their clinical practice or prepared it for submission as academic merit or to a scientific conference. Now in its fourth year, the course has also incorporated training in leadership and quality. As of December 2019, this Infectious Diseases Training Seminar has trained 145 participants from 102 institutions in 48 countries. Graduates of the course formed two professional networks, one in Latin America and another in the Asia Pacific region. Members of the network participate in local capacity building, research, quality improvement, and education in infection care and prevention.

Conclusions
The course has and continues to meet the verbalized need for education and training opportunities in infection care and prevention for the pediatric cancer patient population. Our experience models how targeted training efforts can strengthen the quality of the healthcare workforce for improving outcomes in pediatric cancer care globally.
#71: Single-cell RNA Sequencing Analysis of Zika Virus Infection in Human Stem Cell-Derived Neuroprogenitor Cells and Cerebral Organoids
Authors: Ocwieja K E , Hughes T K , Antonucci J M , Richards A L , Stanton A C , Shalek A , Jaenisch R , Gehrke L 
Published: March 2021

Abstract

Background
The molecular mechanisms underpinning the neurologic and congenital pathologies caused by Zika virus (ZIKV) infection remain poorly understood. It is also unclear why congenital ZIKV disease was not observed prior to the recent epidemics in French Polynesia and the Americas, despite evidence that the Zika virus has actively circulated in parts of Africa and Asia since 1947 and 1966, respectively.

Methods
Due to advances in stem cell-based technologies, we can now model ZIKV infections of the central nervous system in human stem cell-derived neuroprogenitor cells and cerebral organoids, which recapitulate complex three-dimensional neural architecture. We apply Seq-Well—a simple, portable platform for massively parallel single-cell RNA sequencing—to characterize these neural models infected with ZIKV. We detect and quantify host mRNA transcripts and viral RNA with single-cell resolution, thereby defining transcriptional features of both uninfected and infected cells.

Results
In neuroprogenitor cells, single-cell sequencing reveals that while uninfected bystander cells strongly upregulate interferon pathway genes, these are largely suppressed in cells infected with ZIKV within the same culture dish. In our organoid model, single-cell sequencing allows us to identify multiple cellular populations, including neuroprogenitor cells, intermediate progenitor cells, and terminally differentiated neurons. In this model of the developing brain, we identify preferred tropisms of ZIKV infection. Our data additionally reveal differences in cell-type frequencies and gene expression within organoids infected by historic and contemporary ZIKV strains from a variety of geographic locations.

Conclusions
These findings may help explain phenotypic differences attributed to the viruses, including variable propensities to cause microcephaly. Overall, our work provides insight into normal and diseased human brain development and suggests that both virus replication and host response mechanisms underlie the neuropathology of ZIKV infection.
#72: Implementing an Algorithm-based Approach for Treatment of Fever and Neutropenia in Pediatric Oncology Patients in Tegucigalpa, Honduras
Authors: Ordóñez Sara , Luque Marco , Zacasa Pamela , Fu Ligia , Peña Armando , Caniza Miguela , Mukkada Sheena 
Published: March 2021

Abstract

Background
Fever and neutropenia (FN) is a frequent complication in pediatric oncology patients, especially in high-risk patients. In our institution, 43% of acute lymphoblastic leukemia (ALL) patients in induction have at least one hospitalization for FN. A lack of institutional guidelines has led to misuse of antibiotics, prolonged antibiotic wait time and hospitalizations, and unnecessary venipunctures, among others. Implementing an algorithm has provided us with a baseline of previous FN management, and has led to an improvement in management as a whole and to critical areas such as lowering antibiotic wait time in these patients.

Methods
Throughout 2017 we created and revised an algorithm for the management of FN based on current international FN guidelines and, tailored to our specific setting and needs. Orientation began 2 months prior to implementation, with intense training of residents, attendings, and nursing staff one month prior, and for the first 2 months of implementation. Active surveillance of adherence and outcomes, plus periodic retraining has been done throughout implementation. Adherence measurements include antibiotic wait time, use of antibiotics according to risk stratification, number of algorithm deviations, and collection of blood cultures.

Results
Seventy-four patients met inclusion criteria from May 2018 to April 2019. Results were compared between early implementation, (first 3 months: group 1), to the remaining 9 months of the first year (group 2). Time to initial evaluation decreased by 75%, from 76.8 minutes in group 1 to 20.6 minutes in group 2 (P &lt; 0.05). Antibiotic wait time decreased by 54.9%, from 5.18 hours to 2.3 hours (P = 0.0074). Time to blood culture was reduced by 65.3%, from 248 minutes to 85 minutes (P = 0.0040). Incorrect use of antibiotics according to risk stratification decreased by 59.2%, from 42% in group 1 to 17% in group 2 (P = 0.10). Total number of deviations decreased from 1.39 per patient to 1.17 per patient (P = 0.22; Table 1).

Conclusions
Through initial and periodical training and active surveillance, key targets for adherence showed significant improvement throughout the first year of implementation. Maintaining communication with providers through monthly reports of audits, discussions of cases, and retraining improved awareness and willingness to adhere to protocol. Implementation has been particularly useful to residents and attendings outside of the Oncology Ward, where 49% of FN patients in our hospital are treated. It has provided standardized management, improved detection of cases, and reduced delays in care.
#20: Bloodstream Infections in Pediatric Hematology/Oncology Patients: 3 Years’ Experience of a Specialty Pediatrics Hospital in Tuxtla Gutierrez Chiapas. Mexico
Authors: Nava Ruiz E A , Feliciano M , López Argüello C , Caniza M 
Published: March 2021

Abstract

Background
Bloodstream infections are the major cause of morbidity, increased cost, prolonged hospitalization, and mortality in pediatric patients. During treatment, cancer patients require a central vascular access; however, central venous catheters are an important source of bloodstream infections. Rigorous infection control measures and continuous surveillance are required to curb the frequency of these infections.

Objective
We aimed to identify the causative microorganisms in patients with central line–associated bloodstream infection (CLABSI) in hematology-oncology pediatric patients.

Material and Methods
All pediatric hematology-oncology patients with CLABSI of Specialty Pediatrics Hospital between January 2016 and September 2019 were reviewed. We defined CLABSI according to the Centers of Disease Control and Prevention definition. Demographic data and microbiologic isolation were analyzed.

Results
Seventy-five cases of CLABSI in 432 patients (mean age 9.5 years) were reported. The incidence of CLABSI was 0.9/1000 catheter-days (80,232 total catheter-days). Patients with acute lymphoblastic leukemia had the highest infection density 2.5 /1000 patients-day. Coagulase-negative staphylococci was isolated in 38.5% (30/75) of significant blood culture (CoNS 38.5%); P. aeruginosa in 18.6% (14/75); K. pneumoniae in 10.6% (3/75); E. coli in 6.6% (5/75); and Candida tropicalis in 5.3%(4/75) of cases. Enterobacteriaceae were broad-spectrum betalactamase producers; P. aeruginosa was susceptible to antibiotics betalactamics with antipseudomonal action and Candida spp. was susceptible to azoles. We did not use lock antibiotic therapy and all the catheters were removed once CLABSI was diagnosed. Empiric antibiotic treatment in CLABSI in Specialty Pediatrics Hospital based on these findings includes ceftazidime plus vancomycin.

Conclusions
CoNS and P. aeruginosa are the predominant pathogens in CLABSI among pediatric hematology-oncology patient. Antibiotic susceptibility profile has no change during the period of time analyzed, so empiric therapy remains appropriate.
#83: Leukocytes and C-Reactive Protein Levels in Children with Influenza-positive and Influenza-negative Viral Pneumonia in a Third-level Pediatric Center in Mexico City from 2011 to 2016
Authors: Cristerna Tarrasa G H , González Saldaña N , Hernández Porras M , Fortes Gutiérrez S 
Published: March 2021

Abstract

Background
Influenza has been a major source of morbidity and mortality worldwide. Children are one of the most susceptible groups for severe influenza. Clinical differentiation between viral and bacterial pneumonia is difficult to assess in children, so the aid of the complete blood count (CBC) and C-reactive protein (CRP) are used to differentiate between them. However, differential diagnosis between influenza-positive and -negative viral pneumonia is difficult. CRP levels have been found to be higher in H1N1 influenza adult patients. However, there are no studies regarding CBC, and CRP levels in pediatric patients with influenza-positive and -negative pneumonia.

Methods
From 2011 to 2016, we found children less than 18 years old with viral pneumonia who had positive viral RT–PCR test for adenovirus, bocavirus, influenza, parainfluenza, metapneumovirus, rhinovirus, coronavirus or respiratory syncytial virus (RSV). Means for white blood cells (WBC), neutrophils, lymphocytes and CRP were calculated. Comparisons between influenza and other respiratory viral pneumonia WBC and CRP means were made. Student’s t-test was used for statistical analysis.

Results
We analyzed 183 patients with positive viral pneumonia cases; of which, 37 (20.2%) had two viruses detected. Mean age was 1 year old and 56.5% were male. Viral detections were rhinovirus 75 (40.9%), RSV 45 (24.5%), influenza 31 (16.9%), metapneumovirus 30 (16.3%), bocavirus 20 (10.9%), parainfluenza 14 (7.6%), coronavirus 3 (1.6%) and adenovirus 2 (1.1%). Mean influenza WBC were 10,900 ± 2040/μL, neutrophils were 6998 ± 1510/μL, lymphocytes 2882 ± 826/μL and CRP 5.41 ± 1.9 mg/dL. Mean influenza negative, viral-positive pneumonia were WBC 12227 ± 868/μL, neutrophils 6787 ± 696/μL, lymphocytes 4469 ± 426/μL, CRP 2.81 ± 0.56 mg/dL. Lower lymphocyte counts (P = 0.002) and higher CRP levels (P = 0.019) were found in patients with influenza comparing them with pneumonia caused by other viruses.

Conclusions
In our study, children with positive influenza pneumonia showed lower levels of lymphocytes and higher levels of CRP compared with negative influenza. Lower lymphocyte counts and high CRP levels have been found in influenza-positive patients mainly in adult studies. In children with suspected influenza pneumonia, lower lymphocyte counts and higher CRP levels can aid clinical diagnosis before molecular confirmation in influenza pneumonia.
The Impacts of Unrecognized Language and Cultural Barriers During an Educational and Training Activity
Authors: Owens Michael D , Nzumba Franck A 
Published: March 2021

ABSTRACT
Language and cultural barriers are associated with poor health outcomes. Communication is arguably the most important variable associated with a successful educational and training Global Health Engagement (GHE) and often unrecognized even when attempts are made to address this barrier. Madagascar’s GHE activity improved after the addition of local Malagasy translation to fully translated official French instruction.