Genetic diversity of collaborative cross mice enables identification of novel rift valley fever virus encephalitis model.

Rift Valley fever (RVF) is an arboviral disease of humans and livestock responsible for severe economic and human health impacts. In humans, RVF spans a variety of clinical manifestations, ranging from an acute flu-like illness to severe forms of disease, including late-onset encephalitis. The large variations in human RVF disease are inadequately represented by current murine models, which overwhelmingly die of early-onset hepatitis. Existing mouse models of RVF encephalitis are either immunosuppressed, display an inconsistent phenotype, or develop encephalitis only when challenged via intranasal or aerosol exposure. In this study, the genetically defined recombinant inbred mouse resource known as the Collaborative Cross (CC) was used to identify mice with additional RVF disease phenotypes when challenged via a peripheral foot-pad route to mimic mosquito-bite exposure. Wild-type Rift Valley fever virus (RVFV) challenge of 20 CC strains revealed three distinct disease phenotypes: early-onset hepatitis, mixed phenotype, and late-onset encephalitis. Strain CC057/Unc, with the most divergent phenotype, which died of late-onset encephalitis at a median of 11 days post-infection, is the first mouse strain to develop consistent encephalitis following peripheral challenge. CC057/Unc mice were directly compared to C57BL/6 mice, which uniformly succumb to hepatitis within 2-4 days of infection. Encephalitic disease in CC057/Unc mice was characterized by high viral RNA loads in brain tissue, accompanied by clearance of viral RNA from the periphery, low ALT levels, lymphopenia, and neutrophilia. In contrast, C57BL/6 mice succumbed from hepatitis at 3 days post-infection with high viral RNA loads in the liver, viremia, high ALT levels, lymphopenia, and thrombocytopenia. The identification of a strain of CC mice as an RVFV encephalitis model will allow for future investigation into the pathogenesis and treatment of RVF encephalitic disease and indicates that genetic background makes a major contribution to RVF disease variation.

Daprodustat: A Hypoxia-Inducible Factor-Prolyl Hydroxylase Inhibitor for Anemia of Chronic Kidney Disease.

OBJECTIVE: The objective was to review the safety and efficacy of daprodustat, a hypoxia-inducible factor-prolyl hydroxylase inhibitor (HIF-PHI) in the treatment of anemia of chronic kidney disease (CKD). DATA SOURCES: A literature search was conducted in MEDLINE, EMBASE, and ClinicalTrials.gov using the keywords "daprodustat," "GSK1278863," and "hypoxia-inducible factor-prolyl hydroxylase inhibitors" from January 2010 through November 2023. STUDY SELECTION AND DATA EXTRACTION: Literature was included if it evaluated pharmacology, pharmacokinetics, efficacy, and/or safety of daprodustat in human subjects and was reported in English. The manufacturer's product monograph was also utilized. DATA SYNTHESIS: Daprodustat significantly increased hemoglobin levels in CKD patients on dialysis (difference 0.18 g/dL) and not on dialysis (difference 0.08 g/dL) over 52-week treatment periods compared with erythropoiesis stimulating agents (ESA) in Anemia Studies in CKD: Erythropoiesis via a Novel PHI Daprodustat (ASCEND)-D and ASCEND-ND, respectively. First occurrence of major adverse cardiovascular events (MACEs) was similar between daprodustat and ESAs in both trials. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING DRUGS: Daprodustat can be used in patients with CKD on dialysis and already receiving an ESA for at least 6 weeks to further increase serum hemoglobin levels without increasing the risk of MACE. Adverse effects of daprodustat that may occur more than ESAs include headache, emesis, and thrombosis. CONCLUSIONS: Daprodustat is a novel oral, non-iron therapy for treatment of anemia of CKD. It was Food and Drug Administration approved in 2023 in patients already receiving dialysis for at least 4 months but not in non-dialysis patients. Long-term data for safety and additional benefits are pending.

Impact of altered mental status on antibiotic prescribing and outcomes in hospitalized patients presenting with pyuria.

BACKGROUND: Pyuria is nonspecific and may result in over-treatment of asymptomatic bacteriuria (ASB). The Infectious Diseases Society of America recommends against antibiotic treatment of ASB for most patients including those presenting with altered mental status (AMS). Close observation is recommended over treatment to avoid missing alternative causes of AMS and overuse of antibiotics resulting in adverse events and resistance. OBJECTIVES: The purpose of this study was to evaluate patient outcomes associated with antibiotic treatment of pyuria in patients presenting with AMS at hospital admission without specific urinary tract infection (UTI) symptoms. The primary objective was to compare 30-day readmission rates of patients with pyuria and AMS treated with antibiotics (AMS+Tx) versus those who were not treated (AMS-NoTx). Secondary outcomes included identifying risk factors for antibiotic treatment, comparing alternative diagnoses for AMS, and comparing safety outcomes. METHODS: This retrospective cohort study evaluated adult patients with AMS and pyuria (10 WBC/hpf) admitted between February 1, 2020 and October 1, 2021, in a 350-bed community teaching hospital. Patients with documented urinary symptoms were excluded. Additional exclusion criteria included admission to critical care, history of renal transplant, urological surgery, coinfections, pregnancy, and neutropenia. RESULTS: Two-hundred patients were included (AMS+Tx, n = 162; AMS-NoTx, n=38). There was no difference in 30-day hospital readmission rate for AMS between groups (AMS+Tx 16.7% vs AMS-NoTx 23.7%, P = 0.311). An alternative diagnosis of AMS occurred more frequently when antibiotics were withheld (AMS+Tx 66% vs. AMS-NoTx 86.8%, P = 0.012). Urinalyses showing bacteria (odds ratio 2.52; 95% CI, 1.11-5.731) and positive urine culture (OR 3.36; 95% CI, 1.46-7.711) were associated with antibiotic prescribing. CONCLUSIONS: Inappropriate antibiotic use is common among hospitalized patients presenting with AMS and pyuria; however, treatment of asymptomatic pyuria did not decrease rates of subsequent readmission for AMS or retreatment of symptomatic UTI. Patients who were monitored off antibiotics had higher rates of alternative AMS diagnosis.

Optical mapping of cardiac electromechanics in beating in vivo hearts.

Optical mapping has been widely used in the study of cardiac electrophysiology in motion-arrested, ex vivo heart preparations. Recent developments in motion artifact mitigation techniques have made it possible to optically map beating ex vivo hearts, enabling the study of cardiac electromechanics using optical mapping. However, the ex vivo setting imposes limitations on optical mapping such as altered metabolic states, oversimplified mechanical loads, and the absence of neurohormonal regulation. In this study, we demonstrate optical electromechanical mapping in an in vivo heart preparation. Swine hearts were exposed via median sternotomy. Voltage-sensitive dye, either di-4-ANEQ(F)PTEA or di-5-ANEQ(F)PTEA, was injected into the left anterior descending artery. Fluorescence was excited by alternating green and amber light for excitation ratiometry. Cardiac motion during sinus and paced rhythm was tracked using a marker-based method. Motion tracking and excitation ratiometry successfully corrected most motion artifact in the membrane potential signal. Marker-based motion tracking also allowed simultaneous measurement of epicardial deformation. Reconstructed membrane potential and mechanical deformation measurements were validated using monophasic action potentials and sonomicrometry, respectively. Di-5-ANEQ(F)PTEA produced longer working time and higher signal/noise ratio than di-4-ANEQ(F)PTEA. In addition, we demonstrate potential applications of the new optical mapping system including electromechanical mapping during vagal nerve stimulation, fibrillation/defibrillation. and acute regional ischemia. In conclusion, although some technical limitations remain, optical mapping experiments that simultaneously image electrical and mechanical function can be conducted in beating, in vivo hearts.

A Caenorhabditis elegans model of adenylosuccinate lyase deficiency reveals neuromuscular and reproductive phenotypes of distinct etiology.

Inborn errors of purine metabolism are rare syndromes with an array of complex phenotypes in humans. One such disorder, adenylosuccinate lyase deficiency (ASLD), is caused by a decrease in the activity of the bi-functional purine biosynthetic enzyme adenylosuccinate lyase (ADSL). Mutations in human ADSL cause epilepsy, muscle ataxia, and autistic-like symptoms. Although the genetic basis of ASLD is known, the molecular mechanisms driving phenotypic outcome are not. Here, we characterize neuromuscular and reproductive phenotypes associated with a deficiency of adsl-1 in Caenorhabditis elegans. We demonstrate that adsl-1 function contributes to regulation of spontaneous locomotion, that adsl-1 functions acutely for proper mobility, and that aspects of adsl-1-related dysfunction are reversible. Using pharmacological supplementation, we correlate phenotypes with distinct metabolic perturbations. The neuromuscular defect correlates with accumulation of a purine biosynthetic intermediate whereas reproductive deficiencies can be ameliorated by purine supplementation, indicating differing molecular mechanisms behind the phenotypes. Because purine metabolism is highly conserved in metazoans, we suggest that similar separable metabolic perturbations result in the varied symptoms in the human disorder and that a dual-approach therapeutic strategy may be beneficial.

Functional elucidation of TfuA in peptide backbone thioamidation.

YcaO enzymes catalyze several post-translational modifications on peptide substrates, including thioamidation, which substitutes an amide oxygen with sulfur. Most predicted thioamide-forming YcaO enzymes are encoded adjacent to TfuA, which when present, is required for thioamidation. While activation of the peptide amide backbone is well established for YcaO enzymes, the function of TfuA has remained enigmatic. Here we characterize the TfuA protein involved in methyl-coenzyme M reductase thioamidation and demonstrate that TfuA catalyzes the hydrolysis of thiocarboxylated ThiS (ThiS-COSH), a proteinaceous sulfur donor, and enhances the affinity of YcaO toward the thioamidation substrate. We also report a crystal structure of a TfuA, which displays a new protein fold. Our structural and mutational analyses of TfuA have uncovered conserved binding interfaces with YcaO and ThiS in addition to revealing a hydrolase-like active site featuring a Ser-Lys catalytic pair.

Assignment of the absolute configuration of molecules that are chiral by virtue of deuterium substitution using chiral tag molecular rotational resonance spectroscopy.

Chiral tag molecular rotational resonance (MRR) spectroscopy is used to assign the absolute configuration of molecules that are chiral by virtue of deuterium substitution. Interest in the improved performance of deuterated active pharmaceutical ingredients has led to the development of precision deuteration reactions. These reactions often generate enantioisotopomer reaction products that pose challenges for chiral analysis. Chiral tag rotational spectroscopy uses noncovalent derivatization of the enantioisotopomer to create the diastereomers of the 1:1 molecular complexes of the analyte and a small, chiral molecule. Assignment of the absolute configuration requires high-confidence determinations of the structures of these weakly bound complexes. A general search method, CREST, is used to identify candidate geometries. Subsequent geometry optimization using dispersion corrected density functional theory gives equilibrium geometries with sufficient accuracy to identify the isomers of the chiral tag complexes produced in the pulsed jet expansion used to introduce the sample into the MRR spectrometer. Rotational constant scaling based on the fact that the diastereomers have the same equilibrium geometry gives accurate predictions allowing identification of the homochiral and heterochiral tag complexes and, therefore, assignment of absolute configuration. The method is successfully applied to three oxygenated substrates from enantioselective Cu-catalyzed alkene transfer hydrodeuteration reaction chemistry.

Biomarker sST2 in Adults with Transposition of the Great Arteries Palliated by Mustard Procedure: A Five-Year Follow-up.

The Mustard procedure was an early cardiac surgery for transposition of the great arteries (TGA). Despite being successful, it has been associated with long-term arrhythmias and heart failure. A key factor complicating management in adults with congenital heart disease (CHD) is the deficiency of biomarkers predicting outcome. Soluble suppression of tumorogenicity-2 (sST2) is secreted by cardiomyocytes in response to mechanical strain and fibrosis. We hypothesized that adults with a Mustard procedure would have higher levels of sST2 than healthy individuals, and this would correlate with clinical outcome. We performed a single-center study in patients managed during childhood with a Mustard procedure versus age-matched controls. Clinical and demographic data were collected and biomarkers (sST2, cTnI, BNP, lipid panel, insulin, and glucose) were obtained. There were 18 patients (12 male) in the Mustard cohort and 18 patients (6 male) in the control group (22-49 years, mean of 35.8 vs. mean 32.6 years, respectively, p = ns). Nine Mustard subjects were NYHA class II, and 9 subjects were class III. The control group was asymptomatic. sST2 in the Mustard group was elevated in 56% vs. 17% in controls (p = 0.035). Of the Mustard subjects with elevated sST2, 60% had elevated cTnI and BNP, and 90% had low HDL. Over five years, the Mustard patients with elevated sST2 values had greater medication use, arrhythmias, hospitalizations, and ablation/pacer implantations than Mustard subjects with normal sST2. Mustard subjects with elevated sST2 had other biomarker abnormalities and clinically worse outcomes. Thus, sST2 may add a predictive value to cardiac-related morbidity and mortality.

Heterotrimeric Kinesin II is required for flagellar assembly and elongation of nuclear morphology during spermiogenesis in Schmidtea mediterranea.

Development of sperm requires microtubule-based movements that drive assembly of a compact head and flagellated tails. Much is known about how flagella are built given their shared molecular core with motile cilia, but less is known about the mechanisms that shape the sperm head. The Kinesin Superfamily Protein 3A (KIF3A) pairs off with a second motor protein (KIF3B) and the Kinesin Associated Protein 3 (KAP3) to form Heterotrimeric Kinesin II. This complex drives intraflagellar transport (IFT) along microtubules during ciliary assembly. We show that KIF3A and KAP3 orthologs in Schmidtea mediterranea are required for axonemal assembly and nuclear elongation during spermiogenesis. Expression of Smed-KAP3 is enriched during planarian spermatogenesis with transcript abundance peaking in spermatocyte and spermatid cells. Disruption of Smed-kif3A or Smed-KAP3 expression by RNA-interference results in loss of spermatozoa and accumulation of unelongated spermatids. Confocal microscopy of planarian testis lobes stained with alpha-tubulin antibodies revealed that spermatids with disrupted Kinesin II function fail to assemble flagella, and visualization with 4',6-diamidino-2-phenylindole (DAPI) revealed reduced nuclear elongation. Disruption of Smed-kif3A or Smed-KAP3 expression also resulted in edema, reduced locomotion, and loss of epidermal cilia, which corroborates with somatic phenotypes previously reported for Smed-kif3B. These findings demonstrate that heterotrimeric Kinesin II drives assembly of cilia and flagella, as well as rearrangements of nuclear morphology in developing sperm. Prolonged activity of heterotrimeric Kinesin II in manchette-like structures with extended presence during spermiogenesis is hypothesized to result in the exaggerated nuclear elongation observed in sperm of turbellarians and other lophotrochozoans.

Identification and Characterization of Rift Valley Fever Virus-Specific T Cells Reveals a Dependence on CD40/CD40L Interactions for Prevention of Encephalitis.

Rift Valley fever virus (RVFV) is an arbovirus found throughout Africa. It causes disease that is typically mild and self-limiting; however, some infected individuals experience severe manifestations, including hepatitis, encephalitis, or even death. Reports of RVFV encephalitis are notable among immunosuppressed individuals, suggesting a role for adaptive immunity in preventing this severe complication. This phenomenon has been modeled in C57BL/6 mice depleted of CD4 T cells prior to infection with DelNSs RVFV (RVFV containing a deletion of nonstructural protein NSs), resulting in late-onset encephalitis accompanied by high levels of viral RNA in the brain in 30% of animals. In this study, we sought to define the specific type(s) of CD4 T cells that mediate protection from RVFV encephalitis. The viral epitopes targeted by CD4 and CD8 T cells were defined in C57BL/6 mice, and tetramers for both CD4 and CD8 T cells were generated. RVFV-specific CD8 T cells were expanded and of a cytotoxic and proliferating phenotype in the liver following infection. RVFV-specific CD4 T cells were identified in the liver and spleen following infection and phenotyped as largely Th1 or Tfh subtypes. Knockout mice lacking various aspects of pathways important in Th1 and Tfh development and function were used to demonstrate that T-bet, CD40, CD40L, and major histocompatibility complex class II (MHC-II) mediated protection from RVFV encephalitis, while gamma interferon (IFN-γ) and interleukin-12 (IL-12) were dispensable. Virus-specific antibody responses correlated with protection from encephalitis in all mouse strains, suggesting that Tfh/B cell interactions modulate clinical outcome in this model. IMPORTANCE The prevention of RVFV encephalitis requires intact adaptive immunity. In this study, we developed reagents to detect RVFV-specific T cells and provide evidence for Tfh cells and CD40/CD40L interactions as critical mediators of this protection.

Sex Differences in Nicotine Enhancement of Conditioned Place Avoidance Driven by Footshock in Male and Female Rats.

INTRODUCTION: Tobacco use is driven by nicotine, which can enhance the ability of non-nicotine stimuli, including aversive stimuli, to alter behavior. Sex differences exist in the reinforcement enhancement properties of nicotine, but the degree to which this extends to nicotine's ability to enhance behavior driven by aversive stimuli is unclear. AIMS AND METHODS: The current study used adult male and female Sprague-Dawley rats to explore sex differences in nicotine enhancement of footshock (FS)-conditioned place avoidance. FS-conditioned and control rats were tested for conditioned avoidance of FS- or control-paired chambers after injections of saline or nicotine (0.3 mg/kg, subcutaneously). RESULTS: FS supported place avoidance in both male and female rats, and nicotine enhanced avoidance. Females showed more avoidance after nicotine than males, even in nonconditioned control rats. CONCLUSIONS: These results support the idea that sex differences do exist in nicotine enhancement of aversive stimuli, and suggest the mechanisms through which nicotine supports tobacco dependence in males and females may differ. IMPLICATIONS: Nicotine enhancement of nondrug stimuli is thought to play a role in tobacco dependence. Yet previous research of enhancement has overwhelmingly used male subjects and appetitive stimuli. Our findings confirm that nicotine also enhances behavior driven by aversive stimuli, and suggests that females may be more susceptible to nicotine enhancement. Such sex differences suggest sex may be an important factor to consider in treating dependence.

The efficacy of add-ons: selected IVF "add-on" procedures and future directions.

Since the advent of ART, technology has continuously evolved to improve embryology and pregnancy outcomes. However, not all technologies that are integrated into practice have convincing evidence of clinical effectiveness, and they often increase the financial burden of fertility care. We discuss here a selection of commonly utilized IVF "add-ons" and discuss the existing evidence for their utility. The procedures included in this review are time-lapse imaging of embryos, assisted hatching, EmbryoGlue, sperm DNA testing, egg activation with calcium ionophore, endometrial receptivity array, and physiological intracytoplasmic sperm injection (PICSI). While there is rather limited supporting evidence for nearly all IVF add-ons that we reviewed, there is strong demand from patients, physicians, and the biotechnology industry to continue further research and development in this arena. We propose that all add-on procedures should provide true efficacy for the patient, and reproductive endocrinologists should inform patients of the costs and benefits of utilizing various technologies before they undergo treatment. In the future, add-ons that show clear evidence of efficacy and justifiable cost should be incorporated into routine practice, while others that do not meet these criteria should be phased out entirely.

A Review of Posterior Fossa Lesions.

Posterior fossa lesions can occur in patients of all ages. Patients present with subtle findings of hearing loss, tinnitus, headache, cranial neuropathies, imbalance, vertigo, nausea, and vomiting depending on the location and type of lesion. The presentation can be particularly insidious as the most common symptom is slowly progressive hearing loss. Posterior fossa lesions should be included in the differential diagnosis for patients with this presentation and appropriate audiologic testing and imaging should be performed. Management involves collaboration between multiple subspecialties and has evolved significantly over the years leading to increased patient involvement and improved outcomes.

Enantioselective Synthesis of Enantioisotopomers with Quantitative Chiral Analysis by Chiral Tag Rotational Spectroscopy.

Fundamental to the synthesis of enantioenriched chiral molecules is the ability to assign absolute configuration at each stereogenic center, and to determine the enantiomeric excess for each compound. While determination of enantiomeric excess and absolute configuration is often considered routine in many facets of asymmetric synthesis, the same determinations for enantioisotopomers remains a formidable challenge. Here, we report the first highly enantioselective metal-catalyzed synthesis of enantioisotopomers that are chiral by virtue of deuterium substitution along with the first general spectroscopic technique for assignment of the absolute configuration and quantitative determination of the enantiomeric excess of isotopically chiral molecules. Chiral tag rotational spectroscopy uses noncovalent chiral derivatization, which eliminates the possibility of racemization during derivatization, to perform the chiral analysis without the need of reference samples of the enantioisotopomer.

Access to and safety of COVID-19 convalescent plasma in the United States Expanded Access Program: A national registry study.

BACKGROUND: The United States (US) Expanded Access Program (EAP) to coronavirus disease 2019 (COVID-19) convalescent plasma was initiated in response to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19. While randomized clinical trials were in various stages of development and enrollment, there was an urgent need for widespread access to potential therapeutic agents. The objective of this study is to report on the demographic, geographical, and chronological characteristics of patients in the EAP, and key safety metrics following transfusion of COVID-19 convalescent plasma. METHODS AND FINDINGS: Mayo Clinic served as the central institutional review board for all participating facilities, and any US physician could participate as a local physician-principal investigator. Eligible patients were hospitalized, were aged 18 years or older, and had-or were at risk of progression to-severe or life-threatening COVID-19; eligible patients were enrolled through the EAP central website. Blood collection facilities rapidly implemented programs to collect convalescent plasma for hospitalized patients with COVID-19. Demographic and clinical characteristics of all enrolled patients in the EAP were summarized. Temporal patterns in access to COVID-19 convalescent plasma were investigated by comparing daily and weekly changes in EAP enrollment in response to changes in infection rate at the state level. Geographical analyses on access to convalescent plasma included assessing EAP enrollment in all national hospital referral regions, as well as assessing enrollment in metropolitan areas and less populated areas that did not have access to COVID-19 clinical trials. From April 3 to August 23, 2020, 105,717 hospitalized patients with severe or life-threatening COVID-19 were enrolled in the EAP. The majority of patients were 60 years of age or older (57.8%), were male (58.4%), and had overweight or obesity (83.8%). There was substantial inclusion of minorities and underserved populations: 46.4% of patients were of a race other than white, and 37.2% of patients were of Hispanic ethnicity. Chronologically and geographically, increases in the number of both enrollments and transfusions in the EAP closely followed confirmed infections across all 50 states. Nearly all national hospital referral regions enrolled and transfused patients in the EAP, including both in metropolitan and in less populated areas. The incidence of serious adverse events was objectively low (<1%), and the overall crude 30-day mortality rate was 25.2% (95% CI, 25.0% to 25.5%). This registry study was limited by the observational and pragmatic study design that did not include a control or comparator group; thus, the data should not be used to infer definitive treatment effects. CONCLUSIONS: These results suggest that the EAP provided widespread access to COVID-19 convalescent plasma in all 50 states, including for underserved racial and ethnic minority populations. The study design of the EAP may serve as a model for future efforts when broad access to a treatment is needed in response to an emerging infectious disease. TRIAL REGISTRATION: ClinicalTrials.gov NCT#: NCT04338360.

Per-Oral Endoscopic Myotomy for Esophagogastric Junction Outflow Obstruction: A Multicenter Pilot Study.

Esophagogastric junction outflow obstruction (EGJOO) is a rare but increasingly recognized diagnosis as described by The Chicago Classification of Esophageal Motility Disorders version 3.0 (version 3.0).1 On high-resolution manometry (HRM), EGJOO is characterized by increased integrated relaxation pressure (IRP) of the lower esophageal sphincter (LES), yet with some preserved esophageal peristalsis.2-4 Little consensus exists on the preferred therapeutic approach.3 Although conceptually per-oral endoscopic myotomy (POEM) should address the measurable dysfunction in the LES, few data exist to support this.5 Thus, we aimed to evaluate the safety and efficacy of POEM for the treatment of symptomatic EGJOO.

How do I facilitate a rapid response to a public health emergency requiring plasma collection with a public-private partnership?

In March 2020, there were no treatment options for COVID-19. Passive immune therapy including anti-SARS-CoV-2 hyperimmune globulin (hIVIG) was a logical candidate for COVID-19 therapeutic trials, given past success treating emerging pathogens with endogenous neutralizing antibodies. We established a plasma collection protocol for persons recovered from COVID-19. To speed recruitment in the first U.S. hotspot, Seattle, Washington, federal and state public health agencies collaborated with Bloodworks Northwest to collect convalescent plasma (CP) for manufacturing hIVIG. During March-December 2020, we identified and recruited prospective CP donors via letters to persons recovered from COVID-19 with laboratory-confirmed SARS-CoV-2 infection. Prospective donors were pre-screened and administered a medical history survey. Anti-SARS-CoV-2 neutralizing antibody (NAb) titers were classified as qualifying (≥1:80) or non-qualifying (<1:80) for enrollment based on a live virus neutralization assay. Generalized estimating equations were used to identify characteristics of donors associated with qualifying versus nonqualifying NAb titers. Overall, 21,359 letters resulted in 3207 inquiries, 2159 prescreenings with laboratory-confirmed SARS-CoV-2 infection, and 573 donors (27% of all pre-screenings with confirmed infection) who provided a screening plasma donation. Of 573 donors screened, 254 (44%) provided plasma with qualifying NAb titers, resulting in 1284 units for hIVIG manufacture. In a multivariable model, after adjusting for other factors, time (60 days) from COVID-19 symptom onset to screening was associated with lower odds of qualifying NAb (adjusted odds ratio = 0.67, 95% CI: 0.48-0.94). The collaboration facilitated a rapid response to develop and provide hIVIG for clinical trials and CP for transfusion. Only 1 in 12 donor inquiries resulted in a qualifying plasma donation. Challenges included recruitment and the relatively low percentage of persons with high NAb titers and limited screening capacity. This resource-intensive collaboration may not be scalable but informs preparedness and response strategies for plasma collection in future epidemics. Operational readiness plans with templates for screening, consent, and data collection forms are recommended.

Conserved roles for receptor tyrosine kinase extracellular regions in regulating receptor and pathway activity.

Receptor Tyrosine Kinases (RTKs) comprise a diverse group of cell-surface receptors that mediate key signaling events during animal development and are frequently activated in cancer. We show here that deletion of the extracellular regions of 10 RTKs representing 7 RTK classes or their substitution with the dimeric immunoglobulin Fc region results in constitutive receptor phosphorylation but fails to result in phosphorylation of downstream signaling effectors Erk or Akt. Conversely, substitution of RTK extracellular regions with the extracellular region of the Epidermal Growth Factor Receptor (EGFR) results in increases in effector phosphorylation in response to EGF. These results indicate that the activation signal generated by the EGFR extracellular region is capable of activating at least seven different RTK classes. Failure of phosphorylated Fc-RTK chimeras or RTKs with deleted extracellular regions to stimulate phosphorylation of downstream effectors indicates that either dimerization and receptor phosphorylation per se are insufficient to activate signaling or constitutive dimerization leads to pathway inhibition.

Assessing the Dissemination of COVID-19 Articles Across Social Media With Altmetric and PlumX Metrics: Correlational Study.

BACKGROUND: The use of social media assists in the distribution of COVID-19 information to the general public and health professionals. Alternative-level metrics (ie, altmetrics) and PlumX metrics are new bibliometrics that can assess how many times a scientific article has been shared and how much a scientific article has spread within social media platforms. OBJECTIVE: Our objective was to characterize and compare the traditional bibliometrics (ie, citation count and impact factors) and new bibliometrics (ie, Altmetric Attention Score [AAS] and PlumX score) of the top 100 COVID-19 articles with the highest AASs. METHODS: The top 100 articles with highest AASs were identified with Altmetric Explorer in May 2020. The AASs, journal names, and the number of mentions in various social media databases of each article were collected. Citation counts and PlumX Field-Weighted Citation Impact scores were collected from the Scopus database. Additionally, AASs, PlumX scores, and citation counts were log-transformed and adjusted by +1 for linear regression, and Spearman correlation coefficients were used to determine correlations. RESULTS: The median AAS, PlumX score, and citation count were 4922.50, 37.92, and 24.00, respectively. The New England Journal of Medicine published the most articles (18/100, 18%). The highest number of mentions (985,429/1,022,975, 96.3%) were found on Twitter, making it the most frequently used social media platform. A positive correlation was observed between AAS and citation count (r2=0.0973; P=.002), and between PlumX score and citation count (r2=0.8911; P<.001). CONCLUSIONS: Our study demonstrated that citation count weakly correlated with AASs and strongly correlated with PlumX scores, with regard to COVID-19 articles at this point in time. Altmetric and PlumX metrics should be used to complement traditional citation counts when assessing the dissemination and impact of a COVID-19 article.

Individual culture leads to decreased blastocyst formation but does not affect pregnancy outcomes in the setting of a single, vitrified-warmed euploid blastocyst transfer.

PURPOSE: To evaluate embryology and pregnancy outcomes following individual and group embryo culture in the setting of contemporary laboratory practices and freeze-all cycles. METHODS: Patients underwent ovarian stimulation followed by intracytoplasmic sperm injection (ICSI). Embryos proceeded through individual culture and then underwent preimplantation genetic testing for aneuploidy (PGT-A) via trophectoderm biopsy. In a subsequent cycle, participants underwent single embryo transfer of a vitrified-warmed, euploid embryo. Outcomes were compared to controls undergoing group culture during the same time frame. The Mann-Whitney U test and logistic regression models were utilized. RESULTS: Outcomes were assessed for 144 patients whose embryos underwent individual culture and 449 controls whose embryos underwent group culture. There were no significant differences in fertilization rates between groups (81.7% for individual culture vs. 84.1% for group culture, p = 0.22). However, individual culture was associated with a decreased rate of blastocyst formation compared to group culture (43.5% vs. 48.5%, p < 0.01). Following single, vitrified-warmed euploid blastocyst transfer, there were no significant differences between individual culture and group culture, respectively, in rates of positive ßhCG (81.9% vs. 81.5%, p = 0.91), sustained implantation (63.9% vs. 65.0%, p = 0.80), biochemical miscarriage (16.7% vs. 12.3%, p = 0.18), or clinical miscarriage (1.4% vs. 4.2%, p = 0.13). CONCLUSION: While individual culture appears to negatively impact the rate of usable blastocyst formation compared to group culture, there were no significant differences in pregnancy outcomes following transfer of a single, vitrified-warmed euploid blastocyst.