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1.
JCI Insight ; 7(13)2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35801588

RESUMO

BACKGROUNDProlonged symptoms after SARS-CoV-2 infection are well documented. However, which factors influence development of long-term symptoms, how symptoms vary across ethnic groups, and whether long-term symptoms correlate with biomarkers are points that remain elusive.METHODSAdult SARS-CoV-2 reverse transcription PCR-positive (RT-PCR-positive) patients were recruited at Stanford from March 2020 to February 2021. Study participants were seen for in-person visits at diagnosis and every 1-3 months for up to 1 year after diagnosis; they completed symptom surveys and underwent blood draws and nasal swab collections at each visit.RESULTSOur cohort (n = 617) ranged from asymptomatic to critical COVID-19 infections. In total, 40% of participants reported at least 1 symptom associated with COVID-19 six months after diagnosis. Median time from diagnosis to first resolution of all symptoms was 44 days; median time from diagnosis to sustained symptom resolution with no recurring symptoms for 1 month or longer was 214 days. Anti-nucleocapsid IgG level in the first week after positive RT-PCR test and history of lung disease were associated with time to sustained symptom resolution. COVID-19 disease severity, ethnicity, age, sex, and remdesivir use did not affect time to sustained symptom resolution.CONCLUSIONWe found that all disease severities had a similar risk of developing post-COVID-19 syndrome in an ethnically diverse population. Comorbid lung disease and lower levels of initial IgG response to SARS-CoV-2 nucleocapsid antigen were associated with longer symptom duration.TRIAL REGISTRATIONClinicalTrials.gov, NCT04373148.FUNDINGNIH UL1TR003142 CTSA grant, NIH U54CA260517 grant, NIEHS R21 ES03304901, Sean N Parker Center for Allergy and Asthma Research at Stanford University, Chan Zuckerberg Biohub, Chan Zuckerberg Initiative, Sunshine Foundation, Crown Foundation, and Parker Foundation.


Assuntos
COVID-19 , COVID-19/complicações , Humanos , Imunoglobulina G , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
2.
Cell Rep Med ; 3(7): 100680, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35839768

RESUMO

The biological determinants underlying the range of coronavirus 2019 (COVID-19) clinical manifestations are not fully understood. Here, over 1,400 plasma proteins and 2,600 single-cell immune features comprising cell phenotype, endogenous signaling activity, and signaling responses to inflammatory ligands are cross-sectionally assessed in peripheral blood from 97 patients with mild, moderate, and severe COVID-19 and 40 uninfected patients. Using an integrated computational approach to analyze the combined plasma and single-cell proteomic data, we identify and independently validate a multi-variate model classifying COVID-19 severity (multi-class area under the curve [AUC]training = 0.799, p = 4.2e-6; multi-class AUCvalidation = 0.773, p = 7.7e-6). Examination of informative model features reveals biological signatures of COVID-19 severity, including the dysregulation of JAK/STAT, MAPK/mTOR, and nuclear factor κB (NF-κB) immune signaling networks in addition to recapitulating known hallmarks of COVID-19. These results provide a set of early determinants of COVID-19 severity that may point to therapeutic targets for prevention and/or treatment of COVID-19 progression.


Assuntos
COVID-19 , Humanos , NF-kappa B/metabolismo , Proteômica , SARS-CoV-2 , Transdução de Sinais
3.
Allergy ; 77(1): 173-185, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34080210

RESUMO

BACKGROUND: It is unclear whether asthma and its allergic phenotype are risk factors for hospitalization or severe disease from SARS-CoV-2. METHODS: All patients over 28 days old testing positive for SARS-CoV-2 between March 1 and September 30, 2020, were retrospectively identified and characterized through electronic analysis at Stanford. A sub-cohort was followed prospectively to evaluate long-term COVID-19 symptoms. RESULTS: 168,190 patients underwent SARS-CoV-2 testing, and 6,976 (4.15%) tested positive. In a multivariate analysis, asthma was not an independent risk factor for hospitalization (OR 1.12 [95% CI 0.86, 1.45], p = .40). Among SARS-CoV-2-positive asthmatics, allergic asthma lowered the risk of hospitalization and had a protective effect compared with non-allergic asthma (OR 0.52 [0.28, 0.91], p = .026); there was no association between baseline medication use as characterized by GINA and hospitalization risk. Patients with severe COVID-19 disease had lower eosinophil levels during hospitalization compared with patients with mild or asymptomatic disease, independent of asthma status (p = .0014). In a patient sub-cohort followed longitudinally, asthmatics and non-asthmatics had similar time to resolution of COVID-19 symptoms, particularly lower respiratory symptoms. CONCLUSIONS: Asthma is not a risk factor for more severe COVID-19 disease. Allergic asthmatics were half as likely to be hospitalized with COVID-19 compared with non-allergic asthmatics. Lower levels of eosinophil counts (allergic biomarkers) were associated with a more severe COVID-19 disease trajectory. Recovery was similar among asthmatics and non-asthmatics with over 50% of patients reporting ongoing lower respiratory symptoms 3 months post-infection.


Assuntos
Asma , COVID-19 , Asma/diagnóstico , Asma/epidemiologia , Teste para COVID-19 , Humanos , Fenótipo , Estudos Retrospectivos , SARS-CoV-2
4.
Nat Commun ; 12(1): 5417, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521836

RESUMO

COVID-19 is associated with a wide range of clinical manifestations, including autoimmune features and autoantibody production. Here we develop three protein arrays to measure IgG autoantibodies associated with connective tissue diseases, anti-cytokine antibodies, and anti-viral antibody responses in serum from 147 hospitalized COVID-19 patients. Autoantibodies are identified in approximately 50% of patients but in less than 15% of healthy controls. When present, autoantibodies largely target autoantigens associated with rare disorders such as myositis, systemic sclerosis and overlap syndromes. A subset of autoantibodies targeting traditional autoantigens or cytokines develop de novo following SARS-CoV-2 infection. Autoantibodies track with longitudinal development of IgG antibodies recognizing SARS-CoV-2 structural proteins and a subset of non-structural proteins, but not proteins from influenza, seasonal coronaviruses or other pathogenic viruses. We conclude that SARS-CoV-2 causes development of new-onset IgG autoantibodies in a significant proportion of hospitalized COVID-19 patients and are positively correlated with immune responses to SARS-CoV-2 proteins.


Assuntos
Autoanticorpos/imunologia , COVID-19/imunologia , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Idoso , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Autoanticorpos/sangue , Autoantígenos/imunologia , Doenças do Tecido Conjuntivo/imunologia , Citocinas/imunologia , Feminino , Hospitalização , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/patogenicidade , Proteínas Virais/imunologia
5.
RSC Adv ; 8(33): 18227-18233, 2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35541118

RESUMO

During electron microscopy observations of uranium-bearing phases and solutions in a liquid cell, the electron beam induced radiolysis causes changes in the chemistry of the system. This could be useful for investigating accelerated alteration of UO2 and can be also used to monitor radiolytic effects. Low concentrations of bromide in aqueous solutions are known to reduce the generation rate of H2O2 during radiolysis and increase H2 production. We deduced the presence of radiolytic H2O2 by monitoring the formation of a uranyl peroxide solid from both solid UO2 and a solution of ammonium uranyl carbonate at neutral pH. Additionally, the effect of bromine on water radiolysis was investigated through chemical modelling and in situ electron microscopy. By measuring the contrast in the electron microscopy images it was possible to monitor H2O2 formation and diffusion from the irradiated zone in agreement with the models.

6.
Heliyon ; 3(2): e00242, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28217750

RESUMO

We announce a new class of carbon allotropes. The basis of this new classification resides on the concept of combining hexagonal diamond (sp3 bonded carbon - lonsdaleite) and ring carbon (sp2 bonded carbon - graphene). Since hexagonal diamond acts as an insulator and sp2 bonded rings act as conductors, these predicted materials have potential applications for transistors and other electronic components. We describe the structure of a proposed series of carbon allotropes, novamene, and carry out a detailed computational analysis of the structural and electronic properties of the simplest compound in this class: the single-ring novamene. In addition, we suggest how hundreds of different allotropes of carbon could be constructed within this class.

7.
J Phys Chem A ; 118(51): 12105-10, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25423148

RESUMO

We report on a subtle global feature of the mass action kinetics equations for water radiolysis that results in predictions of a critical behavior in H2O2 and associated radical concentrations. While radiolysis kinetics have been studied extensively in the past, it is only in recent years that high-speed computing has allowed the rapid exploration of the solution over widely varying dose and compositional conditions. We explore the radiolytic production of H2O2 under various externally fixed conditions of molecular H2 and O2 that have been regarded as problematic in the literature-specifically, "jumps" in predicted concentrations, and inconsistencies between predictions and experiments have been reported for α radiolysis. We computationally map-out a critical concentration behavior for α radiolysis kinetics using a comprehensive set of reactions. We then show that all features of interest are accurately reproduced with 15 reactions. An analytical solution for steady-state concentrations of the 15 reactions reveals regions in [H2] and [O2] where the H2O2 concentration is not unique-both stable and unstable concentrations exist. The boundary of this region can be characterized analytically as a function of G-values and rate constants independent of dose rate. Physically, the boundary can be understood as separating a region where a steady-state H2O2 concentration exists from one where it does not exist without a direct decomposition reaction. We show that this behavior is consistent with reported α radiolysis data and that no such behavior should occur for γ radiolysis. We suggest experiments that could verify or discredit a critical concentration behavior for α radiolysis and could place more restrictive ranges on G-values from derived relationships between them.

8.
Med Phys ; 34(1): 49-54, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17278489

RESUMO

The purpose of this study was to calculate a more accurate dose rate constant for the 131Cs (model CS-1, IsoRay Medical, Inc., Richland, WA) interstitial brachytherapy seed. Previous measurements of the dose rate constant for this seed have been reported by others with incongruity. Recent direct measurements by thermoluminescence dosimetry and by gamma-ray spectroscopy were about 15% greater than earlier thermoluminescence dosimetry measurements. Therefore, we set about to calculate independent values by a Monte Carlo approach that combined three estimates as a consistency check, and to quantify the computational uncertainty. The calculated dose rate constant for the 131Cs seed was 1.040 cGy h(-1) U(-1) for an ionization chamber model and 1.032 cGy h(-1) U(-1) for a circular ring model. A formal value of 2.2% uncertainty was calculated for both values. The range of our multiestimate values were from 1.032 to 1.061 cGy h(-1) U(-1). We also modeled three 125I seeds with known dose rate constants to test the accuracy of this study's approach.


Assuntos
Braquiterapia/instrumentação , Braquiterapia/métodos , Radioisótopos de Césio/análise , Radioisótopos de Césio/uso terapêutico , Modelos Biológicos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Carga Corporal (Radioterapia) , Simulação por Computador , Modelos Estatísticos , Método de Monte Carlo , Dosagem Radioterapêutica , Eficiência Biológica Relativa
9.
Clin Occup Environ Med ; 4(4): 621-56, v-vi, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15465472

RESUMO

Reports of injury began after the introduction of chlorinated solvents in the 1920s. In 1987, the National Institute for Occupational Safety and Health reported that 9.8 million workers were exposed to organic solvents in occupational settings, with most of these exposures being to mixtures of solvents. Although solvent mixtures have been noted to be responsible for neuropathy, seizures, and encephalopathy, identifying the culpable agent has been difficult, because the associations between many solvents and their biologic effects have not been well defined, and solvent interaction in mixtures have not been well or easily characterized. In some cases, these exposures have been estimated to be below levels designated in regulations as acceptable for workers.


Assuntos
Solventes/efeitos adversos , Algoritmos , Humanos , Síndromes Neurotóxicas/diagnóstico , Síndromes Neurotóxicas/etiologia , Compostos Orgânicos/efeitos adversos
10.
Environ Health Perspect ; 110(12): 1261-6, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12460807

RESUMO

A 28-year-old female presented for evaluation of left flank pain and polyuria after having been exposed to cadmium in the jewelry manufacturing industry for approximately 3 years. This patient possessed both elevated 24-hr urinary ss2-microglobulin and elevated blood cadmium levels. Approximately 6 months after initial presentation, the patient resigned from her job due to shortness of breath, chest pain, and anxiety. Exposure to cadmium in the jewelry industry is a significant source of occupational cadmium exposure. Other occupational sources include the manufacture of nickel-cadmium batteries, metal plating, zinc and lead refining, smelting of cadmium and lead, and production of plastics. Cadmium is also an environmental pollutant that accumulates in leafy vegetables and plants, including tobacco. Major toxicities anticipated from cadmium exposure involve the renal, pulmonary, and, to a lesser extent, gastrointestinal systems. These include the development of renal proximal tubular dysfunction, glomerular damage with progressive renal disease, and respiratory symptoms including pneumonitis and emphysema. Low-level cadmium exposure has also been associated with increased urinary calcium excretion and direct bone toxicity, effects that recent research suggests may result in the development of osteoporosis. The body burden of cadmium, over half of which may reside in the kidneys, is most often measured through the use of urinary cadmium levels. Blood cadmium measurements generally reflect current or recent exposure and are especially useful in cases with a short exposure period and only minimal accumulation of cadmium in the kidneys. Both ss2-microglobulin and alpha1-microglobulin serve as organ-specific, early-effect biomarkers of tubular proteinuria and thus play a role in identifying early signs of cadmium-induced renal damage in those with potential exposures. In addition to ensuring workplace compliance with Occupational Safety and Health Administration-mandated monitoring and screening measures, it is prudent for those with cadmium exposure to maintain adequate intake of both iron and calcium, appropriate measures even in the absence of exposure.


Assuntos
Cádmio/efeitos adversos , Nefropatias/etiologia , Metalurgia , Exposição Ocupacional , Adulto , Biomarcadores/análise , Carga Corporal (Radioterapia) , Cádmio/sangue , Feminino , Humanos , Nefropatias/patologia , Osteoporose/etiologia , Microglobulina beta-2/sangue
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