Incidence estimates of hospitalizations for community-acquired pneumonia among children in the United States that are based on prospective data collection are limited. Updated estimates of pneumonia ...that has been confirmed radiographically and with the use of current laboratory diagnostic tests are needed.
We conducted active population-based surveillance for community-acquired pneumonia requiring hospitalization among children younger than 18 years of age in three hospitals in Memphis, Nashville, and Salt Lake City. We excluded children with recent hospitalization or severe immunosuppression. Blood and respiratory specimens were systematically collected for pathogen detection with the use of multiple methods. Chest radiographs were reviewed independently by study radiologists.
From January 2010 through June 2012, we enrolled 2638 of 3803 eligible children (69%), 2358 of whom (89%) had radiographic evidence of pneumonia. The median age of the children was 2 years (interquartile range, 1 to 6); 497 of 2358 children (21%) required intensive care, and 3 (<1%) died. Among 2222 children with radiographic evidence of pneumonia and with specimens available for bacterial and viral testing, a viral or bacterial pathogen was detected in 1802 (81%), one or more viruses in 1472 (66%), bacteria in 175 (8%), and both bacterial and viral pathogens in 155 (7%). The annual incidence of pneumonia was 15.7 cases per 10,000 children (95% confidence interval CI, 14.9 to 16.5), with the highest rate among children younger than 2 years of age (62.2 cases per 10,000 children; 95% CI, 57.6 to 67.1). Respiratory syncytial virus was more common among children younger than 5 years of age than among older children (37% vs. 8%), as were adenovirus (15% vs. 3%) and human metapneumovirus (15% vs. 8%). Mycoplasma pneumoniae was more common among children 5 years of age or older than among younger children (19% vs. 3%).
The burden of hospitalization for children with community-acquired pneumonia was highest among the very young, with respiratory viruses the most commonly detected causes of pneumonia. (Funded by the Influenza Division of the National Center for Immunization and Respiratory Diseases.).
Low plasma arginine bioavailability has been implicated in endothelial dysfunction and immune dysregulation. The role of arginine in COVID-19 is unknown, but could contribute to cellular damage if ...low. Our objective was to determine arginine bioavailability in adults and children with COVID-19 vs. healthy controls. We hypothesized that arginine bioavailability would be low in patients with COVID-19 and multisystem inflammatory syndrome in children (MIS-C). We conducted a prospective observational study of three patient cohorts; arginine bioavailability was determined in asymptomatic healthy controls, adults hospitalized with COVID-19, and hospitalized children/adolescents <21 y old with COVID-19, MIS-C, or asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection identified on admission screen. Mean patient plasma amino acids were compared to controls using the Student's
test. Arginine-to-ornithine ratio, a biomarker of arginase activity, and global arginine bioavailability ratio (GABR, arginine/ornithine+citrulline) were assessed in all three groups. A total of 80 patients were included (28 controls, 32 adults with COVID-19, and 20 pediatric patients with COVID-19/MIS-C). Mean plasma arginine and arginine bioavailability ratios were lower among adult and pediatric patients with COVID-19/MIS-C compared to controls. There was no difference between arginine bioavailability in children with COVID-19 vs. MIS-C. Adults and children with COVID-19 and MIS-C in our cohort had low arginine bioavailability compared to healthy adult controls. This may contribute to immune dysregulation and endothelial dysfunction in COVID-19. Low arginine-to-ornithine ratio in patients with COVID-19 or MIS-C suggests an elevation of arginase activity. Further study is merited to explore the role of arginine dysregulation in COVID-19.
Infants with premature birth ≤35 weeks gestational age, chronic lung disease of prematurity and congenital heart disease are at an increased risk for lower respiratory tract infections and ...hospitalization from respiratory syncytial virus (RSV), which has been shown in randomized trials to be prevented by palivizumab. However, palivizumab effectiveness (PE) has not been studied in a large clinical setting.
A multicenter study among high-risk US and Canadian children younger than 24 months hospitalized with lower respiratory tract infection and whose nasopharyngeal aspirates were tested for human metapneumovirus (HMPV) and RSV were the subjects of the trial. We conducted a test-negative case-control study in these subjects to determine PE. We used an inverse propensity score weighted (IPSW) multiple logistic regression model to adjust PE.
Palivizumab was used in 434 (51%) of 849 eligible children. RSV was identified in 403 (47%) children. The unadjusted PE was 43% 95% confidence interval (CI), 34%-51%). After IPSW adjustment, the adjusted PE was 58% (95% CI, 43%-69%). Palivizumab prevented intensive care unit admissions (PE, 62%; 95% CI, 35%-78%). PE for 29-35 weeks gestational age and ≤6 months of chronologic age without chronic lung disease of prematurity or congenital heart disease was 74% (95% CI, 56%-85%).
Using a test-negative case-control design with RSV molecular detection, palivizumab is shown to prevent RSV hospitalizations and intensive care unit admissions in high-risk infants.
Since the COVID-19 pandemic, functional non-neutralizing antibody responses to SARS-CoV-2, including antibody-dependent cell-mediated cytotoxicity (ADCC), are poorly understood. We developed an ADCC ...assay utilizing a stably transfected, dual-reporter target cell line with inducible expression of a SARS-CoV-2 spike protein on the cell surface. Using this assay, we analyzed 61 convalescent serum samples from adults with PCR-confirmed COVID-19 and 15 samples from healthy uninfected controls. We found that 56 of 61 convalescent serum samples induced ADCC killing of SARS-CoV-2 S target cells, whereas none of the 15 healthy controls had detectable ADCC. We then found a modest decline in ADCC titer over a median 3-month follow-up in 21 patients who had serial samples available for analysis. We confirmed that the antibody-dependent target cell lysis was mediated primarily via the NK FcγRIIIa receptor (CD16). This ADCC assay had high sensitivity and specificity for detecting serologic immune responses to SARS-CoV-2.
•Inducible EGFP and Luciferase dual reporters target cell line.•Antibody-Dependent Cell-mediated Cytotoxicity (ADCC) to SARS-CoV-2 spike protein.•Cell lysis mediated primarily via the NK FcγRIIIa receptor (CD16).•Functional SARS-CoV-2 spike (S) protein-based ADCC antibody assay.
We study asset pricing in economies featuring both risk and uncertainty. In our empirical analysis, we measure risk via return volatility and uncertainty via the degree of disagreement of ...professional forecasters, attributing different weights to each forecaster. We empirically model the typical risk-return trade-off and augment these models with our measure of uncertainty. We find stronger empirical evidence for an uncertainty-return trade-off than for the traditional risk-return trade-off. Finally, we investigate the performance of a two-factor model with risk and uncertainty in the cross section.
Respiratory syncytial virus (RSV) can cause severe disease in adults with cardiopulmonary conditions, such as congestive heart failure (CHF). We quantified the rate of RSV-associated hospitalization ...in adults by CHF status using population-based surveillance in the United States.
Population-based surveillance for RSV (RSV-NET) was performed in 35 counties in seven sites during two respiratory seasons (2015-2017) from October 1-April 30. Adults (≥18 years) admitted to a hospital within the surveillance catchment area with laboratory-confirmed RSV identified by clinician-directed testing were included. Presence of underlying CHF was determined by medical chart abstraction. We calculated overall and age-stratified (<65 years and ≥65 years) RSV-associated hospitalization rates by CHF status. Estimates were adjusted for age and the under-detection of RSV. We also report rate differences (RD) and rate ratios (RR) by comparing the rates for those with and without CHF.
2042 hospitalized RSV cases with CHF status recorded were identified. Most (60.2%, n = 1230) were ≥65 years, and 28.3% (n = 577) had CHF. The adjusted RSV hospitalization rate was 26.7 (95% CI: 22.2, 31.8) per 10,000 population in adults with CHF versus 3.3 (95% CI: 3.3, 3.3) per 10,000 in adults without CHF (RR: 8.1, 95% CI: 6.8, 9.7; RD: 23.4, 95% CI: 18.9, 28.5). Adults with CHF had higher rates of RSV-associated hospitalization in both age groups (<65 years and ≥65 years). Adults ≥65 years with CHF had the highest rate (40.5 per 10,000 population, 95% CI: 35.1, 46.6).
Adults with CHF had 8 times the rate of RSV-associated hospitalization compared with adults without CHF. Identifying high-risk populations for RSV infection can inform future RSV vaccination policies and recommendations.
Background. Recent trials suggest procalcitonin-based guidelines can reduce antibiotic use for respiratory infections. However, the accuracy of procalcitonin to discriminate between viral and ...bacterial pneumonia requires further dissection. Methods. We evaluated the association between serum procalcitonin concentration at hospital admission with pathogens detected in a multicenter prospective surveillance study of adults hospitalized with community-acquired pneumonia. Systematic pathogen testing included cultures, serology, urine antigen tests, and molecular detection. Accuracy of procalcitonin to discriminate between viral and bacterial pathogens was calculated. Results. Among 1735 patients, pathogens were identified in 645 (37%), including 169 (10%) with typical bacteria, 67 (4%) with atypical bacteria, and 409 (24%) with viruses only. Median procalcitonin concentration was lower with viral pathogens (0.09 ng/mL; interquartile range IQR, <0.05–0.54 ng/mL) than atypical bacteria (0.20 mg/mL; IQR, <0.05–0.87 ng/mL; P = .05), and typical bacteria (2.5 ng/mL; IQR, 0.29–12.2 ng/mL; P < .01). Procalcitonin discriminated bacterial pathogens, including typical and atypical bacteria, from viral pathogens with an area under the receiver operating characteristic (ROC) curve of 0.73 (95% confidence interval CI, .69–.77). A procalcitonin threshold of 0.1 ng/mL resulted in 80.9% (95% CI, 75.3%–85.7%) sensitivity and 51.6% (95% CI, 46.6%–56.5%) specificity for identification of any bacterial pathogen. Procalcitonin discriminated between typical bacteria and the combined group of viruses and atypical bacteria with an area under the ROC curve of 0.79 (95% CI, .75–.82). Conclusions. No procalcitonin threshold perfectly discriminated between viral and bacterial pathogens, but higher procalcitonin strongly correlated with increased probability of bacterial pathogens, particularly typical bacteria.
Influenza may contribute to the burden of acute cardiovascular events during annual influenza epidemics.
To examine acute cardiovascular events and determine risk factors for acute heart failure ...(aHF) and acute ischemic heart disease (aIHD) in adults with a hospitalization associated with laboratory-confirmed influenza.
Cross-sectional study.
U.S. Influenza Hospitalization Surveillance Network during the 2010-to-2011 through 2017-to-2018 influenza seasons.
Adults hospitalized with laboratory-confirmed influenza and identified through influenza testing ordered by a practitioner.
Acute cardiovascular events were ascertained using discharge codes from the International Classification of Diseases (ICD), Ninth Revision, Clinical Modification, and ICD, 10th Revision. Age, sex, race/ethnicity, tobacco use, chronic conditions, influenza vaccination, influenza antiviral medication, and influenza type or subtype were included as exposures in logistic regression models, and marginal adjusted risk ratios and 95% CIs were estimated to describe factors associated with aHF or aIHD.
Among 89 999 adults with laboratory-confirmed influenza, 80 261 had complete medical record abstractions and available ICD codes (median age, 69 years interquartile range, 54 to 81 years) and 11.7% had an acute cardiovascular event. The most common such events (non-mutually exclusive) were aHF (6.2%) and aIHD (5.7%). Older age, tobacco use, underlying cardiovascular disease, diabetes, and renal disease were significantly associated with higher risk for aHF and aIHD in adults hospitalized with laboratory-confirmed influenza.
Underdetection of cases was likely because influenza testing was based on practitioner orders. Acute cardiovascular events were identified by ICD discharge codes and may be subject to misclassification bias.
In this population-based study of adults hospitalized with influenza, almost 12% of patients had an acute cardiovascular event. Clinicians should ensure high rates of influenza vaccination, especially in those with underlying chronic conditions, to protect against acute cardiovascular events associated with influenza.
Centers for Disease Control and Prevention.
Logarithmic depreciation Anderson, Evan W.; Brock, William
Economic modelling,
August 2021, 2021-08-00, Letnik:
101
Journal Article
Recenzirano
Odprti dostop
This paper studies logarithmic depreciation which is similar to conventional geometric depreciation, except that capital and investment are replaced by their logarithms. We provide empirical and ...theoretical evidence that logarithmic depreciation can account for aggregate capital depreciation better than geometric depreciation and better than more complicated methods that have additional parameters. We document that consumption and investment decisions in the United States and other countries appear to be made under the erroneous assumption that aggregate capital approximately depreciates geometrically and the welfare losses from doing so are large.
•Market decision makers believe aggregate capital depreciates geometrically.•Aggregate capital actually depreciates logarithmically.•Welfare losses from depreciation model misspecification are large.
Electrochemical impedance spectroscopy is frequently used to characterize, optimize, and monitor ion-selective membranes. However, because of the relatively high resistance of ion-selective ...membranes, their impedance spectra often contain artifacts that can cause misinterpretation. While in the high-frequency range artifacts are often readily identifiable by the occurrence of inductive features or negative resistances, artifacts are easy to overlook in the low-frequency range, where telltale characteristics are typically missing. Some artifacts can be avoided by the use of two-electrode cells, but this experimental design makes it hard to distinguish the impedance of the ion-selective membrane from that of the measuring electrodes. This work shows that experimental data can be analyzed accurately with the use of models that account for the capacitive leakage present in the reference channels of the impedance spectrometer. To test these models, valinomycin-doped K+-selective membranes were studied by electrochemical impedance spectroscopy with two-, three-, and four-electrode cells, using several measuring electrodes with low to high impedances. The models were found to correctly predict experimental data and provide an intuitive understanding of the cause of the impedance artifacts. This understanding can be applied to design electrochemical impedance spectroscopy experiments of ion-selective membranes with three- and four-electrode cells that minimize artifacts.
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