13 research outputs found

    The sensitivity of benzene cluster cation chemical ionization mass spectrometry to select biogenic terpenes

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    The datasets used in the Lavi et al publication are included here.Benzene cluster cations are a sensitive and selective reagent ion for chemical ionization of select biogenic volatile organic compounds. We have previously reported the sensitivity of a field deployable chemical ionization time-of-flight mass spectrometer (CI-ToFMS), using benzene cluster cation ion chemistry, for detection of dimethyl sulfide, isoprene and α-pinene. Here, we present laboratory measurements of the sensitivity of the same instrument to a series of terpenes, including isoprene, α-pinene, β-pinene, D-limonene, ocimene, β-myrcene, farnesene, α-humulene, β-caryophyllene, and isolongifolene at atmospherically relevant mixing ratios (< 100 pptv). In addition, we determine the dependence of CI-ToFMS sensitivity on the reagent ion neutral delivery concentration and water vapor concentration. We show that isoprene is primarily detected as an adduct (C5H8 ⋅ C6H+6) with a sensitivity ranging between 4 and 10 ncps ppt−1, which depends strongly on the reagent ion precursor concentration, de-clustering voltages, and specific humidity (SH). Monoterpenes are detected primarily as the molecular ion (C10H+16) with an average sensitivity, across the five measured compounds, of 14 ± 3 ncps ppt−1 for SH between 7 and 14 g kg−1, typical of the boreal forest during summer. Sesquiterpenes are detected primarily as the molecular ion (C15H+24) with an average sensitivity, across the four measured compounds, of 9.6 ± 2.3 ncps ppt−1, that is also independent of specific humidity. Comparable sensitivities across broad classes of terpenes (e.g., monoterpenes and sesquiterpenes), coupled to the limited dependence on specific humidity, suggest that benzene cluster cation CI-ToFMS is suitable for field studies of biosphere–atmosphere interactions.This work was supported by a National Science Foundation (NSF) CAREER Award (grant no. AGS-1151430) and the Office of Science (Office of Biological and Environmental Research), U.S. Department of Energy (grant no. DE-SC0006431). Avi Lavi gratefully acknowledges support from the Dreyfus Foundation Environmental Chemistry Postdoctoral Fellowship Program

    Characterization of Light-Absorbing Oligomers from Reactions of Phenolic Compounds and Fe(III)

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    Phenolic compounds are common constituents of atmospheric aerosols. They form by pyrolysis of lignin and by biodegradation of plant material and are commonly found in biomass burning plumes, resuspended soil dust, and in anthropogenic secondary organic aerosols (SOA). In this study, we show that reactions of Fe­(III), a major constituent of mineral dust, with several phenolic compounds (guaiacol, catechol, syringol, o- and p-cresol) that are common in atmospheric aerosols, result in the formation of water insoluble light-absorbing compounds and reduced Fe­(II). The study was conducted under acidic conditions (pH = 1–2), relevant for areas impacted by biomass burning, anthropogenic emissions, and mineral dust. The reaction products have been characterized using a high-performance liquid chromatography coupled to photodiode array and high-resolution mass spectrometry detectors, UV–visible spectroscopy, X-ray photoelectron spectroscopy, and thermal gravimetric analysis. The major identified chromophores are oligomers of the reaction precursors that efficiently absorb light between 300 and 500 nm. The amounts of oligomers vary significantly between the systems studied. The highest amount was observed for guaiacol and catechol, and the least were detected in the syringol experiments, suggesting that the oligomerization proceeds through carbon–carbon coupling preferred at para- and ortho- positions, coupled to the reduction of Fe­(III) to Fe­(II). The results suggest that aqueous-phase radical reactions of phenolic compounds may be an efficient source of light-absorbing atmospheric organic compounds (brown carbon) that play important roles in Earth’s radiative forcing on global and regional scales and of quinones that can affect health

    Dysregulated Levels of Circulating Autoantibodies against Neuronal and Nervous System Autoantigens in COVID-19 Patients

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    BACKGROUND: COVID-19 is a heterogenous disease resulting in long-term sequela in predisposed individuals. It is not uncommon that recovering patients endure non-respiratory ill-defined manifestations, including anosmia, and neurological and cognitive deficit persisting beyond recovery-a constellation of conditions that are grouped under the umbrella of long-term COVID-19 syndrome. Association between COVID-19 and autoimmune responses in predisposed individuals was shown in several studies. AIM AND METHODS: To investigate autoimmune responses against neuronal and CNS autoantigens in SARS-CoV-2-infected patients, we performed a cross-sectional study with 246 participants, including 169 COVID-19 patients and 77 controls. Levels of antibodies against the acetylcholine receptor, glutamate receptor, amyloid β peptide, alpha-synucleins, dopamine 1 receptor, dopamine 2 receptor, tau protein, GAD-65, N-methyl D-aspartate (NMDA) receptor, BDNF, cerebellar, ganglioside, myelin basic protein, myelin oligodendrocyte glycoprotein, S100-B, glial fibrillary acidic protein, and enteric nerve were measured using an Enzyme-Linked Immunosorbent Assay (ELISA). Circulating levels of autoantibodies were compared between healthy controls and COVID-19 patients and then classified by disease severity (mild [ = 74], severe [ = 65], and requiring supplemental oxygen [ = 32]). RESULTS: COVID-19 patients were found to have dysregulated autoantibody levels correlating with the disease severity, e.g., IgG to dopamine 1 receptor, NMDA receptors, brain-derived neurotrophic factor, and myelin oligodendrocyte glycoprotein. Elevated levels of IgA autoantibodies against amyloid β peptide, acetylcholine receptor, dopamine 2 receptor, myelin basic protein, and α-synuclein were detected in COVID-19 patients compared with healthy controls. Lower IgA autoantibody levels against NMDA receptors, and IgG autoantibodies against glutamic acid decarboxylase 65, amyloid β peptide, tau protein, enteric nerve, and S100-B were detected in COVID-19 patients versus healthy controls. Some of these antibodies have known clinical correlations with symptoms commonly reported in the long COVID-19 syndrome. CONCLUSIONS: Overall, our study shows a widespread dysregulation in the titer of various autoantibodies against neuronal and CNS-related autoantigens in convalescent COVID-19 patients. Further research is needed to provide insight into the association between these neuronal autoantibodies and the enigmatic neurological and psychological symptoms reported in COVID-19 patients

    Hygroscopic Characteristics of Alkylaminium Carboxylate Aerosols

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    The hygroscopic growth factor (HGF) and cloud condensation nuclei (CCN) activity for a series of alkylaminium carboxylate aerosols have been measured using a hygroscopicity tandem differential mobility analyzer coupled to a condensation particle counter and a CCN counter. The particles, consisting of the mixtures of mono- (acetic, propanoic, <i>p</i>-toluic, and <i>cis</i>-pinonic acid) and dicarboxylic (oxalic, succinic, malic, adipic, and azelaic acid) acid with alkylamine (mono-, di-, and trimethylamines), represent those commonly found under diverse environmental conditions. The hygroscopicity parameter (κ) of the alkylaminium carboxylate aerosols was derived from the HGF and CCN results and theoretically calculated. The HGF at 90% RH is in the range of 1.3 to 1.8 for alkylaminium monocarboxylates and 1.1 to 2.2 for alkylaminium dicarboxylates, dependent on the molecular functionality (i.e., the carboxylic or OH functional group in organic acids and methyl substitution in alkylamines). The κ value for all alkylaminium carboxylates is in the range of 0.06–1.37 derived from the HGF measurements at 90% RH, 0.05–0.49 derived from the CCN measurements, and 0.22–0.66 theoretically calculated. The measured hygroscopicity of the alkylaminium carboxylates increases with decreasing acid to base ratio. The deliquescence point is apparent for several of the alkylaminium dicarboxylates but not for the alkylaminium monocarboxylates. Our results reveal that alkylaminium carboxylate aerosols exhibit distinct hygroscopic and deliquescent characteristics that are dependent on their molecular functionality, hence regulating their impacts on human health, air quality, and direct and indirect radiative forcing on climate

    Severe COVID-19 patients exhibit elevated levels of autoantibodies targeting cardiolipin and platelet glycoprotein with age: a systems biology approach

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    Age is a significant risk factor for the coronavirus disease 2019 (COVID-19) severity due to immunosenescence and certain age-dependent medical conditions (e.g., obesity, cardiovascular disorder, and chronic respiratory disease). However, despite the well-known influence of age on autoantibody biology in health and disease, its impact on the risk of developing severe COVID-19 remains poorly explored. Here, we performed a cross-sectional study of autoantibodies directed against 58 targets associated with autoimmune diseases in 159 individuals with different COVID-19 severity (71 mild, 61 moderate, and 27 with severe symptoms) and 73 healthy controls. We found that the natural production of autoantibodies increases with age and is exacerbated by SARS-CoV-2 infection, mostly in severe COVID-19 patients. Multiple linear regression analysis showed that severe COVID-19 patients have a significant age-associated increase of autoantibody levels against 16 targets (e.g., amyloid β peptide, β catenin, cardiolipin, claudin, enteric nerve, fibulin, insulin receptor a, and platelet glycoprotein). Principal component analysis with spectrum decomposition and hierarchical clustering analysis based on these autoantibodies indicated an age-dependent stratification of severe COVID-19 patients. Random forest analysis ranked autoantibodies targeting cardiolipin, claudin, and platelet glycoprotein as the three most crucial autoantibodies for the stratification of severe COVID-19 patients ≥50 years of age. Follow-up analysis using binomial logistic regression found that anti-cardiolipin and anti-platelet glycoprotein autoantibodies significantly increased the likelihood of developing a severe COVID-19 phenotype with aging. These findings provide key insights to explain why aging increases the chance of developing more severe COVID-19 phenotypes

    Cross-sectional analysis reveals autoantibody signatures associated with COVID-19 severity

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    The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with increased levels of autoantibodies targeting immunological proteins such as cytokines and chemokines. Reports further indicate that COVID-19 patients may develop a broad spectrum of autoimmune diseases due to reasons not fully understood. Even so, the landscape of autoantibodies induced by SARS-CoV-2 infection remains uncharted territory. To gain more insight, we carried out a comprehensive assessment of autoantibodies known to be linked to diverse autoimmune diseases observed in COVID-19 patients in a cohort of 231 individuals, of which 161 were COVID-19 patients (72 with mild, 61 moderate, and 28 with severe disease) and 70 were healthy controls. Dysregulated IgG and IgA autoantibody signatures, characterized mainly by elevated concentrations, occurred predominantly in patients with moderate or severe COVID-19 infection. Autoantibody levels often accompanied anti-SARS-CoV-2 antibody concentrations while stratifying COVID-19 severity as indicated by random forest and principal component analyses. Furthermore, while young versus elderly COVID-19 patients showed only slight differences in autoantibody levels, elderly patients with severe disease presented higher IgG autoantibody concentrations than young individuals with severe COVID-19. This work maps the intersection of COVID-19 and autoimmunity by demonstrating the dysregulation of multiple autoantibodies triggered during SARS-CoV-2 infection. Thus, this cross-sectional study suggests that SARS-CoV-2 infection induces autoantibody signatures associated with COVID-19 severity and several autoantibodies that can be used as biomarkers of COVID-19 severity, indicating autoantibodies as potential therapeutical targets for these patients

    Mental health and resiliency following 44 months of terrorism: a survey of an Israeli national representative sample

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    <p>Abstract</p> <p>Background</p> <p>Israeli citizens have been exposed to intense and ongoing terrorism since September 2000. We previously studied the mental health impact of terrorism on the Israeli population (Bleich et al., 2002), however the long-term impact of ongoing terrorism has not yet been examined. The present study evaluated the psychological sequelae of 44 months of terrorism in Israel, and sought to identify factors that may contribute to vulnerability and resilience.</p> <p>Methods</p> <p>This was a telephone survey using strata sampling of 828 households, which reached a representative sample of 702 adult Israeli residents (84.8% contact rate). In total, 501 people (60.5%) agreed to participate. The methodology was similar to that of our previous study. Exposure to terrorism and other traumatic events, number of traumatic stress-related symptoms (TSRS), percentage of respondents with symptom criteria for post-traumatic stress disorder (PTSD), traumatic stress (TS) resiliency and feelings of depression, anxiety, optimism, sense of safety, and help-seeking were the main outcome measures.</p> <p>Results</p> <p>In total, 56 participants (11.2%) were directly exposed to a terrorist incident, and 101 (20.2%) had family members or friends exposed. Respondents reported a mean ± SD of 5.0 ± 4.5 TSRS; 45 (9%) met symptom criteria for PTSD; and 72 (14.4%) were TS-resilient. There were 147 participants (29.5%) who felt depressed, 50 (10.4%) felt anxious, and almost half (235; 47%) felt life-threatening danger; 48 (9.7%) felt the need for professional help. Women and people of Arab ethnicity had more TSRS, more PTSD, and less TS resiliency. Injury following a life-threatening experience, a major stressful life event, and a major loss of income were associated with PTSD. Immigrant status, lower education, low sense of safety, low sense of social support, high societal distress, and injury following life-threatening experiences were associated with TSRS. TSRS did not increase with exposure severity. This study revealed less depression and functional impairment, similar rates of PTSD, increased help-seeking and poorer TSRS and TS resiliency than our initial study, 2 years previously.</p> <p>Discussion</p> <p>The response of people in Israel to 4 years of terrorism is heterogeneous. Vulnerability factors change over time; Arab ethnicity, immigrant status and less education, not found to be risk factors in our previous study, were found in the present study to contribute to trauma-related distress. Prior experience of highly stressful events increases vulnerability to adverse psychological effects of terror.</p

    Autoantibodies targeting GPCRs and RAS-related molecules associate with COVID-19 severity

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    COVID-19 shares the feature of autoantibody production with systemic autoimmune diseases. In order to understand the role of these immune globulins in the pathogenesis of the disease, it is important to explore the autoantibody spectra. Here we show, by a cross-sectional study of 246 individuals, that autoantibodies targeting G protein-coupled receptors (GPCR) and RAS-related molecules associate with the clinical severity of COVID-19. Patients with moderate and severe disease are characterized by higher autoantibody levels than healthy controls and those with mild COVID-19 disease. Among the anti-GPCR autoantibodies, machine learning classification identifies the chemokine receptor CXCR3 and the RAS-related molecule AGTR1 as targets for antibodies with the strongest association to disease severity. Besides antibody levels, autoantibody network signatures are also changing in patients with intermediate or high disease severity. Although our current and previous studies identify anti-GPCR antibodies as natural components of human biology, their production is deregulated in COVID-19 and their level and pattern alterations might predict COVID-19 disease severity
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