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1.
Atmospheric Chemistry and Physics ; 22(17):11203-11215, 2022.
Article in English | ProQuest Central | ID: covidwho-2025099

ABSTRACT

We use satellite methane observations from the Tropospheric Monitoring Instrument (TROPOMI), for May 2018 to February 2020, to quantify methane emissions from individual oil and natural gas (O/G) basins in the US and Canada using a high-resolution (∼25 km) atmospheric inverse analysis. Our satellite-derived emission estimates show good consistency with in situ field measurements (R=0.96) in 14 O/G basins distributed across the US and Canada. Aggregating our results to the national scale, we obtain O/G-related methane emission estimates of12.6±2.1 Tg a-1 for the US and 2.2±0.6 Tg a-1 for Canada, 80 % and 40 %, respectively, higher than the national inventories reported to the United Nations. About 70 % of the discrepancy in the US Environmental Protection Agency (EPA) inventory can be attributed to five O/G basins, the Permian, Haynesville, Anadarko, Eagle Ford, and Barnett basins, which in total account for 40 % of US emissions. We show more generally that our TROPOMI inversion framework can quantify methane emissions exceeding 0.2–0.5 Tg a-1 from individual O/G basins, thus providing an effective tool for monitoring methane emissions from large O/G basins globally.

2.
J Hematol Oncol ; 15(1): 81, 2022 06 16.
Article in English | MEDLINE | ID: covidwho-1962866

ABSTRACT

Recipients after hematopoietic stem cell transplantation (HSCT) or chimeric antigen receptor T-cell (CAR-T) therapy are at increased risk for unfavorable outcomes after SARS-CoV-2 infection. The efficacy of COVID-19 vaccines remains undetermined in this vulnerable population, we therefore conducted a pooled analysis to evaluate the immune response after vaccination. A total of 46 studies were finally included, comprising 4757 HSCT and 174 CAR-T recipients. Our results indicated that HSCT and CAR-T recipients had an attenuated immune response to SARS-CoV-2 vaccination compared with healthy individuals, while time interval between transplant and vaccination, immunosuppressive therapy (IST) and lymphocyte counts at vaccination significantly affected the humoral response in HSCT recipients. In addition, seroconversion was significantly higher in patients with BCMA-based CAR-T than those with CD19-based CAR-T. Thus, an adapted vaccination strategy for HSCT and CAR-T recipients may be required, and further research on the effect of a booster dose of COVID-19 vaccine and the role of cellular response after vaccination is warranted.


Subject(s)
COVID-19 , Hematopoietic Stem Cell Transplantation , Receptors, Chimeric Antigen , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/therapeutic use , Hematopoietic Stem Cell Transplantation/methods , Humans , Immunity , Immunotherapy, Adoptive/methods , SARS-CoV-2 , Vaccination
3.
EBioMedicine ; 81: 104102, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1906946

ABSTRACT

BACKGROUND: COVID-19 vaccination is recommended for patients with multiple sclerosis (pwMS), while disease-modifying therapies (DMTs) may influence the efficacy of SARS-CoV-2 vaccines in this population. Thus, we conducted a meta-analysis to evaluate the impact of DMTs on immune response to COVID-19 vaccines in pwMS. METHODS: Literature search from December 1, 2019 to March 31, 2022 was performed in PubMed, MedRxiv, Embase and Cochrane Library. The risk of impaired response to vaccination in pwMS receiving DMTs was estimated in odds ratios (ORs) using random-effects method. FINDINGS: A total of 48 studies comprising 6860 pwMS were included. Overall, pwMS with anti-CD20 (OR=0.02, 95% CI: 0.01-0.03) and sphingosine-1-phosphate receptor modulator (S1PRM) (OR=0.03, 95% CI: 0.01-0.06) treatments had attenuated serologic response after full vaccination compared with those without DMTs. Additionally, pwMS vaccinated within six months since last anti-CD20 therapy were at significantly higher risk of blunted response compared with those receiving anti-CD20 therapy more than six months prior to vaccination (P = 0.001). We found no significant associations between other treatments (including IFN-ß, GA, DMF, TERI, NTZ, CLAD, and ALE) and humoral response to SARS-CoV-2 vaccines in pwMS. As for T-cell response, no significant difference was found between pwMS on anti-CD20 and those without DMTs after vaccination, while S1PRM was marginally associated with impaired cellular response (P = 0.03). INTERPRETATION: Our findings suggested that routine serological monitoring may be required for pwMS on anti-CD20 and S1PRMs after SARS-CoV-2 vaccination and highlighted the benefits of a booster dose. The effect of cellular response and optimal interval from last anti-CD20 treatment to vaccination should be further addressed. FUNDING: This study was supported by Natural Science Foundation of Shanghai (21ZR1433000).


Subject(s)
COVID-19 Vaccines , COVID-19 , Multiple Sclerosis , Antigens, CD20 , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , China , Humans , Immunologic Factors/therapeutic use , Multiple Sclerosis/drug therapy , SARS-CoV-2 , Vaccination
5.
Atmospheric Chemistry and Physics ; 21(9):6605-6626, 2021.
Article in English | ProQuest Central | ID: covidwho-1212058

ABSTRACT

Methane emissions associated with the production, transport, and use of oil and natural gas increase the climatic impacts of energy use;however, little is known about how emissions vary temporally and with commodity prices. We present airborne and ground-based data, supported by satellite observations, to measure weekly to monthly changes in total methane emissions in the United States' Permian Basin during a period of volatile oil prices associated with the COVID-19 pandemic. As oil prices declined from ∼ USD 60 to USD 20 per barrel, emissions changed concurrently from 3.3 % to 1.9 % of natural gas production;as prices partially recovered, emissions increased back to near initial values. Concurrently, total oil and natural gas production only declined by∼ 10 % from the peak values seen in the months prior to the crash. Activity data indicate that a rapid decline in well development and subsequent effects on associated gas flaring and midstream infrastructure throughput are the likely drivers of temporary emission reductions. Our results, along with past satellite observations, suggest that under more typical price conditions, the Permian Basin is in a state of overcapacity in which rapidly growing associated gas production exceeds midstream capacity and leads to high methane emissions.

6.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.04.13.439709

ABSTRACT

Several fast-spreading variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have become the dominant circulating strains that continue to fuel the COVID-19 pandemic despite intensive vaccination efforts throughout the world. We report here cryo-EM structures of the full-length spike (S) trimers of the B.1.1.7 and B.1.351 variants, as well as their biochemical and antigenic properties. Mutations in the B.1.1.7 protein increase the accessibility of its receptor binding domain and also the binding affinity for receptor angiotensin-converting enzyme 2 (ACE2). The enhanced receptor engagement can account for the increased transmissibility and risk of mortality as the variant may begin to infect efficiently infect additional cell types expressing low levels of ACE2. The B.1.351 variant has evolved to reshape antigenic surfaces of the major neutralizing sites on the S protein, rendering complete resistance to some potent neutralizing antibodies. These findings provide structural details on how the wide spread of SARS-CoV-2 enables rapid evolution to enhance viral fitness and immune evasion. They may guide intervention strategies to control the pandemic.


Subject(s)
Coronavirus Infections , Infections , COVID-19 , Seizures
7.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Article in English | MEDLINE | ID: covidwho-1112035

ABSTRACT

Surface ozone is a severe air pollution problem in the North China Plain, which is home to 300 million people. Ozone concentrations are highest in summer, driven by fast photochemical production of hydrogen oxide radicals (HOx) that can overcome the radical titration caused by high emissions of nitrogen oxides (NOx) from fuel combustion. Ozone has been very low during winter haze (particulate) pollution episodes. However, the abrupt decrease of NOx emissions following the COVID-19 lockdown in January 2020 reveals a switch to fast ozone production during winter haze episodes with maximum daily 8-h average (MDA8) ozone concentrations of 60 to 70 parts per billion. We reproduce this switch with the GEOS-Chem model, where the fast production of ozone is driven by HOx radicals from photolysis of formaldehyde, overcoming radical titration from the decreased NOx emissions. Formaldehyde is produced by oxidation of reactive volatile organic compounds (VOCs), which have very high emissions in the North China Plain. This remarkable switch to an ozone-producing regime in January-February following the lockdown illustrates a more general tendency from 2013 to 2019 of increasing winter-spring ozone in the North China Plain and increasing association of high ozone with winter haze events, as pollution control efforts have targeted NOx emissions (30% decrease) while VOC emissions have remained constant. Decreasing VOC emissions would avoid further spreading of severe ozone pollution events into the winter-spring season.


Subject(s)
Air Pollution/analysis , Ozone/analysis , Particulate Matter/analysis , Seasons , Volatile Organic Compounds , COVID-19 , China , Crops, Agricultural , Environmental Monitoring , Environmental Pollution , Humans , Nitrogen Oxides/chemistry , Pandemics , Public Health
8.
biorxiv; 2020.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2020.09.18.301952

ABSTRACT

Effective intervention strategies are urgently needed to control the COVID-19 pandemic. Human angiotensin-converting enzyme 2 (ACE2) is a carboxypeptidase that forms a dimer and serves as the cellular receptor for SARS-CoV-2. It is also a key negative regulator of the renin-angiotensin system (RAS), conserved in mammals, which modulates vascular functions. We report here the properties of a trimeric ACE2 variant, created by a structure-based approach, with binding affinity of ~60 pM for the spike (S) protein of SARS-CoV-2, while preserving the wildtype peptidase activity as well as the ability to block activation of angiotensin II receptor type 1 in the RAS. Moreover, the engineered ACE2 potently inhibits infection of SARS-CoV-2 in cell culture. These results suggest that engineered, trimeric ACE2 may be a promising anti-SARS-CoV-2 agent for treating COVID-19.


Subject(s)
COVID-19
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