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1.
medRxiv ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38712108

RESUMO

Background: Prior studies have established the impact of sex differences on pulmonary arterial hypertension (PAH). However, it remains unclear whether these sex differences extend to other hemodynamic subtypes of pulmonary hypertension (PH). Methods: We examined sex differences in PH and hemodynamic PH subtypes in a hospital-based cohort of individuals who underwent right heart catheterization between 2005-2016. We utilized multivariable linear regression to assess the association of sex with hemodynamic indices of RV function [PA pulsatility index (PAPi), RV stroke work index (RVSWI), and right atrial: pulmonary capillary wedge pressure ratio (RA:PCWP)]. We then used Cox regression models to examine the association between sex and clinical outcomes among those with PH. Results: Among 5208 individuals with PH (mean age 64 years, 39% women), there was no significant sex difference in prevalence of PH overall. However, when stratified by PH subtype, 31% of women vs 22% of men had pre-capillary (P<0.001), 39% vs 51% had post-capillary (P=0.03), and 30% vs 27% had mixed PH (P=0.08). Female sex was associated with better RV function by hemodynamic indices, including higher PAPi and RVSWI, and lower RA:PCWP ratio (P<0.001 for all). Over 7.3 years of follow-up, female sex was associated with a lower risk of heart failure hospitalization (HR 0.83, CI 95% CI 0.74- 0.91, p value <0.001). Conclusions: Across a broad hospital-based sample, more women had pre-capillary and more men had post-capillary PH. Compared with men, women with PH had better hemodynamic indices of RV function and a lower risk of HF hospitalization. CLINICAL PERSPECTIVE: What Is New? Although sex differences have been explored in pulmonary arterial hypertension, sex differences across pulmonary hypertension (PH) in broader samples inclusive of all hemodynamic subtypes remain less well definedWe delineate sex differences in hemodynamic subtypes of PH and associated right ventricular function in a large, heterogenous, hospital-based sample of individuals who underwent right heart catheterizationSex has a significant impact on prevalence of PH across hemodynamic subtypes as well as associated RV function What Are the Clinical Implications? Understanding sex differences across different PH hemodynamic subtypes is paramount to refining risk stratification between men and womenFurther elucidating sex differences in associated RV function and clinical outcomes may aid in developing sex-specific therapies or management strategies to improve clinical outcomes.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38773701

RESUMO

Poor interfacial quality and low refractive index contrast (Δn) are critical challenges for the development of high-performance one-dimensional photonic crystals (1DPhCs) via solution methods that impede their optical efficiency. Herein, we introduce an innovative approach by hybridizing hollow SiO2 with poly(vinyl alcohol), referred to as PHS, followed by alternate assembly with TiO2 via spin-coating, achieving a 1DPhC with Δn = 0.76 at the wavelength of 550 nm. This method circumvents the need for high-temperature treatment and complex curing conditions, resulting in a 1DPhC with superior interfacial and optical characteristics. By adjusting the thickness of the PHS layers, we can finely tune the reflectance spectrum, attaining over 99% reflectance at the photonic band gap. Furthermore, 1DPhC demonstrates excellent adhesion to polycarbonate substrates and retains its optimal optical performance even after rigorous environmental testing, including hygrothermal cycles, exposure to hot water, friction, and solvent sonication. This research paves the way for the facile fabrication of high-performance 1DPhCs under mild conditions, offering new perspectives for photonic material processing.

3.
Talanta ; 276: 126289, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38776779

RESUMO

Aggregation-induced emission (AIE) has been widely used in research on electrochemiluminescence (ECL) due to its excellent luminescence intensity. In this work, copper superparticles (Cu SPs) were used to construct ECL biosensor to detect the microRNA-103a (miRNA-103a) in triple-negative breast cancer (TNBC) tumor tissues. Firstly, GSH-capped copper clusters were used as precursors to prepare Cu SPs by the AIE effect. Compared with clusters, Cu SPs possessed higher luminescence performance and energy stability, making them an ideal choice for ECL nanoprobe. The film of PVDF-HFP/CeVO4 NPs was constructed and modified with CPBA and GSH as the sensing interface (PCCG). The PCCG film displayed good conductivity and hydrophilicity, and desirable mechanical stability. Moreover, the PCCG film can induce high carrier mobility rates and dissociate large amounts of the co-reactant K2S2O8 to enhance the ECL intensity of Cu SPs. As a result, the prepared ECL sensor with the catalyzed hairpin assembly (CHA) strategy was employed to quantify miRNA-103a in the range of 100 fM to 100 nM. The biosensor provided a novel analytical approach for the clinical diagnosis of TNBC.

4.
Environ Sci Technol ; 58(20): 8857-8866, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38718183

RESUMO

Comprehensive identification of aerosol sources and their constituent organic compounds requires aerosol-phase molecular-level characterization with a high time resolution. While real-time chemical characterization of aerosols is becoming increasingly common, information about functionalization and structure is typically obtained from offline methods. This study presents a method for determining the presence of carboxylic acid functional groups in real time using extractive electrospray ionization mass spectrometry based on measurements of [M - H + 2Na]+ adducts. The method is validated and characterized using standard compounds. A proof-of-concept application to α-pinene secondary organic aerosol (SOA) shows the ability to identify carboxylic acids even in complex mixtures. The real-time capability of the method allows for the observation of the production of carboxylic acids, likely formed in the particle phase on short time scales (<120 min). Our research explains previous findings of carboxylic acids being a significant component of SOA and a quick decrease in peroxide functionalization following SOA formation. We show that the formation of these acids is commensurate with the increase of dimers in the particle phase. Our results imply that SOA is in constant evolution through condensed-phase processes, which lower the volatility of the aerosol components and increase the available condensed mass for SOA growth and, therefore, aerosol mass loading in the atmosphere. Further work could aim to quantify the effect of particle-phase acid formation on the aerosol volatility distributions.


Assuntos
Aerossóis , Ácidos Carboxílicos , Espectrometria de Massas por Ionização por Electrospray
5.
Environ Sci Atmos ; 4(5): 531-546, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38764888

RESUMO

Iodine oxoacids are recognised for their significant contribution to the formation of new particles in marine and polar atmospheres. Nevertheless, to incorporate the iodine oxoacid nucleation mechanism into global simulations, it is essential to comprehend how this mechanism varies under various atmospheric conditions. In this study, we combined measurements from the CLOUD (Cosmic Leaving OUtdoor Droplets) chamber at CERN and simulations with a kinetic model to investigate the impact of temperature, ionisation, and humidity on iodine oxoacid nucleation. Our findings reveal that ion-induced particle formation rates remain largely unaffected by changes in temperature. However, neutral particle formation rates experience a significant increase when the temperature drops from +10 °C to -10 °C. Running the kinetic model with varying ionisation rates demonstrates that the particle formation rate only increases with a higher ionisation rate when the iodic acid concentration exceeds 1.5 × 107 cm-3, a concentration rarely reached in pristine marine atmospheres. Consequently, our simulations suggest that, despite higher ionisation rates, the charged cluster nucleation pathway of iodic acid is unlikely to be enhanced in the upper troposphere by higher ionisation rates. Instead, the neutral nucleation channel is likely to be the dominant channel in that region. Notably, the iodine oxoacid nucleation mechanism remains unaffected by changes in relative humidity from 2% to 80%. However, under unrealistically dry conditions (below 0.008% RH at +10 °C), iodine oxides (I2O4 and I2O5) significantly enhance formation rates. Therefore, we conclude that iodine oxoacid nucleation is the dominant nucleation mechanism for iodine nucleation in the marine and polar boundary layer atmosphere.

6.
Aquat Toxicol ; 272: 106959, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38768528

RESUMO

As one of the main components of marine pollution, microplastics (MPs) inevitably enter the mussel aquaculture environment. At the same time, pathogenic bacteria, especially pathogens such as Vibrio, can cause illness outbreaks, leading to large-scale death of mussels. The potential harm of MPs and pathogenic bacteria to bivalve remains unclear. This study designed two experiments (1) mussels (Mytilus galloprovincialis) were exposed to 100 particles/L or 1,000 particles/L polymethyl methacrylate (PMMA, 17.01 ± 6.74 µm) MPs and 1 × 107 CFU/mL Vibrio parahaemolyticus at the same time (14 days), and (2) mussels were exposed to 100 particles/L or 1,000 particles/L MPs for a long time (30 days) and then exposed to 1 × 107 CFU/mL V. parahaemolyticus to explore the effects of these two stresses on the mussel immune system. The results showed that after the combined exposure of V. parahaemolyticus and MPs, the lysosomal membrane stability of hemocytes decreased, lysozyme activity was inhibited, and hemocytes were induced to produce more lectins and defensins to fight pathogenic invasion. Long-term exposure to MPs caused a large amount of energy consumption in mussels, inhibited most of the functions of humoral immunity, increased the risk of mussel infection with pathogenic bacteria, and negatively affected mussel condition factor, the number of hemocytes, and the number of byssuses. Mussels may allocate more energy to deal with MPs and pathogenic bacterial infections rather than for growth. Above all, MPs exposure can affect mussel immune function or reduce its stress resistance, which in turn has an impact on mollusk farming.

7.
Mikrochim Acta ; 191(5): 280, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649540

RESUMO

An interfacial galvanic replacement strategy to controllable synthesize palladium nanoparticles (Pd NPs)-modified NiFe MOF nanocomposite on nickel foam, which served as an efficient sensing platform for quantitative determination of dopamine (DA). Pd NPs grown in situ on the nanosheets of NiFe MOF via self-driven galvanic replacement reaction (GRR) and well uniform distribution was achieved. This method effectively reduced the aggregation of metallic nanoparticles and significantly promoted the electron transfer rate during the electrochemical process, leading to improved electrocatalytic activity for DA oxidation. Remarkably, the precisely constructed biosensor achieved a low detection limit (LOD) of 0.068 µM and recovery of 94.1% (RSD 6.7%, N = 3) for simulated real sample detection and also exhibited superior selectivity and stability. The results confirmed that the as-fabricated Pd-NiFe/NF composite electrode could realize the quantitative determination of DA and showed promising prospects in real sample biosensing.


Assuntos
Técnicas Biossensoriais , Dopamina , Estruturas Metalorgânicas , Nanoestruturas , Dopamina/análise , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/normas , Níquel/química , Eletrodos/normas , Paládio/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Microscopia Eletrônica de Varredura , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/ultraestrutura , Sensibilidade e Especificidade , Condutividade Elétrica , Microscopia Eletrônica de Transmissão , Ferro/química , Reprodutibilidade dos Testes
8.
J Ethnopharmacol ; 329: 118164, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593963

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Epimedium sagittatum (Sieb. et Zucc.) Maxim. has been used traditionally in Asia. It can dispel wind and cold, tonify the kidney, and strengthen bones and tendons. However, adverse effects of E. sagittatum have been reported, and the underlying mechanisms remain unclear. AIM OF THE STUDY: This study aimed to investigate liver injury caused by an aqueous extract of E. sagittatum in Institute of Cancer Research (ICR) mice and explore its potential mechanisms. MATERIALS AND METHODS: Dried E. sagittatum leaves were decocted in water to prepare aqueous extracts for ultra-high performance liquid chromatography analysis. Mice were administered an aqueous extract of E. sagittatum equivalent to either 3 g raw E. sagittatum/kg or 10 g raw E. sagittatum/kg once daily via intragastric injection for three months. The liver weights and levels of the serum biochemical parameters including alanine transaminase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total bilirubin (TBIL), and alkaline phosphatase were measured. Hematoxylin-eosin staining was performed for histopathology. Apoptosis was detected using the TUNEL apoptosis assay kit. IL-1ß was detected using ELISA kits. Proteomics was used to identify the differentially expressed proteins. Western blot analysis was performed to determine the levels of proteins significantly affected by the aqueous extract of E. sagittatum. RESULTS: E. sagittatum treatment increased the liver weights and liver coefficients, and ALT and AST levels significantly increased (p < 0.05). A high dose of E. sagittatum significantly increased LDH and TBIL levels (p < 0.05). Ruptured cell membranes and multiple sites of inflammatory cell infiltration were also observed. No evidence of apoptosis was observed. IL-1ß levels were significantly increased (p < 0.05). The expressions of PIK3R1, p-MAP2K4, p-Jun N-terminal kinase (JNK)/JNK, p-c-Jun, VDAC2, Bax, and CYC were upregulated, whereas that of Bcl-2 was inhibited by E. sagittatum. The expression of cleaved caspase-1 was significantly increased; however, its effects on GSDMD and GSDMD-N were significantly decreased. The expression levels of cleaved caspase-3 and its effector proteins GSDME and GSDME-N significantly increased. CONCLUSIONS: Our results suggest that the aqueous extract of E. sagittatum induces liver injury in ICR mice after three months of intragastric injection via inflammatory pyroptosis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Epimedium , Fígado , Camundongos Endogâmicos ICR , Extratos Vegetais , Piroptose , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Masculino , Camundongos , Piroptose/efeitos dos fármacos , Epimedium/química , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Folhas de Planta/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-38621705

RESUMO

PURPOSE: To investigate the association between neonatal birthweight (NBW) discordance and preeclampsia (PE) in twin pregnancy. METHODS: This was a single-center retrospective cohort study. Women with two live births in the First Affiliated Hospital of Sun Yat-sen University from January 2011 to June 2020 were eligible. They were classified into four groups based on the quartiles of NBW discordance in monochorionic (MC) and dichorionic (DC) twin pregnancy. The relationship between NBW discordance and the risk of PE was assessed by logistic regression, subgroup analyses was further analyzed. RESULTS: A total of 1566 women were eligible for the final analysis, there were 445 MC cases and 1121 DC cases. No matter in monochorionic or dichorionic pregnancy, higher NBW discordance quartiles were associated with increased risks of PE. Compared with women in the lowest NBW discordance quartile, women in the highest NBW discordance quartile had approximately 3.6 and 6.0 times risk of PE in monochorionic and dichorionic pregnancy respectively. The association between quartiles of NBW discordance and the risk of PE were higher in dichorionic pregnancy than in monochorionic pregnancy. No matter in MC or DC pregnancy, no significant interaction effects were identified for maternal age, pregnancy body mass index, mode of conception and whether complicated with gestational diabetes mellitus. CONCLUSIONS: The increased NBW discordance quartile was related to an increased risk of PE. Assessing estimated fetal weight discordance by using ultrasound in clinical practice to predict PE remained to be further researched.

10.
Bioresour Technol ; 398: 130510, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432545

RESUMO

Catalytic fast pyrolysis (CFP) is a promising method to convert biomass waste into sustainable bio-oils. However, the relationship gap between biomass characteristics and bio-oil quality has hindered the development of CFP technology. This study investigated the pyrolysis and CFP of ten biomass sources over zeolites, and showed that biomass sources and zeolites played important roles in bio-oil production. For noncatalytic trials, the bio-oil yield was positively related to holocellulose (R2 = 0.75) and volatiles content (R2 = 0.62) but negatively to ash content (R2 = -0.65). The bio-oil quality was dramatically improved after catalyst addition. For CFP over ZSM-5, hydrocarbons selectivity of bio-oils was increased by 1.6∼79.3 times, which was closely related to H/C ratio (R2 = 0.79). For ZSM-5@SBA-15 trials, the dependency of hydrocarbons selectivity on biomass characteristics was less clear than that in ZSM-5 counterparts, although undesirable PAHs were inhibited for most biomass sources. This study demonstrated the influence mechanism of biomass characteristics on bio-oil compositions.


Assuntos
Polifenóis , Zeolitas , Biocombustíveis , Biomassa , Óleos de Plantas , Hidrocarbonetos
11.
Alzheimers Dement ; 20(5): 3290-3304, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38511601

RESUMO

INTRODUCTION: Genome-wide association studies (GWAS) have identified loci associated with Alzheimer's disease (AD) but did not identify specific causal genes or variants within those loci. Analysis of whole genome sequence (WGS) data, which interrogates the entire genome and captures rare variations, may identify causal variants within GWAS loci. METHODS: We performed single common variant association analysis and rare variant aggregate analyses in the pooled population (N cases = 2184, N controls = 2383) and targeted analyses in subpopulations using WGS data from the Alzheimer's Disease Sequencing Project (ADSP). The analyses were restricted to variants within 100 kb of 83 previously identified GWAS lead variants. RESULTS: Seventeen variants were significantly associated with AD within five genomic regions implicating the genes OARD1/NFYA/TREML1, JAZF1, FERMT2, and SLC24A4. KAT8 was implicated by both single variant and rare variant aggregate analyses. DISCUSSION: This study demonstrates the utility of leveraging WGS to gain insights into AD loci identified via GWAS.


Assuntos
Doença de Alzheimer , Estudo de Associação Genômica Ampla , Sequenciamento Completo do Genoma , Humanos , Doença de Alzheimer/genética , Feminino , Masculino , Predisposição Genética para Doença/genética , Idoso , Polimorfismo de Nucleotídeo Único/genética , Variação Genética/genética
12.
Anal Chem ; 96(12): 4909-4917, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38489746

RESUMO

Due to the ideal optical manipulation ability, the metasurface has broad prospects in the development of novel optical research. In particular, an active metasurface can control optical response through external stimulus, which has attracted great research interest. However, achieving effective modulation of the optical response is a significant challenge. In this work, we have developed a novel electrochemiluminescence (ECL) signal modulation strategy by an active magnetoplasmonic metasurface under an external magnetic field. The magnetoplasmonic metasurface was assembled based on yolk-shell Fe3O4@Au nanoparticles (Fe3O4@Au YS-NPs). On the one hand, the yolk-shell structure of Fe3O4@Au YS-NPs possessed the surface plasmon coupling effect and cavity-based Purcell effect, which provided high-intensity electromagnetic hot spots in the magnetoplasmonic metasurface. On the other hand, due to the strong magnetic response of the Fe3O4 core, the local magnetic field was induced by the external magnetic field, which further generated Lorentz force acting on the free electrons of Au nanoshells with strong optical anisotropy. The plasmon frequency of the metasurface can be effectively modulated by the Lorentz force effect. As a result, the ECL signal of nitrogen dots (N dots) was dynamically modulated and significantly enhanced at a specific polarization angle by the magnetoplasmonic metasurface under the variable external magnetic field. Based on the luminescence modulation ability and structure feature, the magnetoplasmonic metasurface was further established successfully as a sensing interface for gastric cancer (GC) extracellular vesicle (EV) detection. This study illustrated that the electromagnetic response of the active metasurface can effectively improve the optical modulation ability and luminescence sensing performance.

13.
Natl Sci Rev ; 11(3): nwae014, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38390366

RESUMO

Organic vapors from biomass burning are a major source of secondary organic aerosols (SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds (VOCs). While intermediate volatility organic compounds (IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ∼70% of the formed SOA, i.e. >2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

14.
ACS Omega ; 9(4): 4974-4985, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313474

RESUMO

Infectious wounds pose a significant challenge in the field of wound healing primarily due to persistent inflammation and the emergence of antibiotic-resistant bacteria. To combat these issues, the development of an effective wound dressing that can prevent infection and promote healing is of the utmost importance. Photodynamic therapy (PDT) has emerged as a promising noninvasive treatment strategy for tackling antibiotic-resistant bacteria. A biodegradable photosensitizer called hematoporphyrin monomethyl ether (HMME) has shown potential in generating reactive oxygen species (ROS) upon laser activation to combat bacteria. However, the insolubility of HMME limits its antibacterial efficacy and its ability to facilitate skin healing. To overcome these limitations, we have synthesized a compound hydrogel by combining carbomer, HMME, and Cu2O nanoparticles. This compound hydrogel exhibits enhanced antimicrobial ability and excellent biocompatibility and promotes angiogenesis, which is crucial for the healing of skin defects. By integrating the benefits of HMME, Cu2O nanoparticles, and the gel-forming properties of carbomer, this compound hydrogel shows great potential as an effective wound dressing material. In summary, the compound hydrogel developed in this study offers a promising solution for infectious wounds by addressing the challenges of infection prevention and promoting skin healing. This innovative approach utilizing PDT and the unique properties of the compound hydrogel could significantly improve the outcomes of wound healing in clinical settings.

15.
Food Chem ; 444: 138594, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38309076

RESUMO

Herein, a novel electrochemiluminescence (ECL) and differential pulse voltammetry (DPV) dual-mode-based molecularly imprinted (MIP) sensor had been established for the detection of enrofloxacin (ENR) in eggs. Firstly, bismuth sulfide quantum dots (Bi2S3 QDs) as ECL luminophore were synthesized. Furthermore, a MIP film with ionic liquid (ILs), Bi2S3 QDs, and ENR was prepared via the electrochemical polymerization procedure on the electrode. As ENR was identified and captured by the imprinted cavities, the electron transfer pathway was blocked on the electrochemical interface, resulting in the decrease of both DPV signals and ECL signals. As a novel synchronous dual-mode sensing strategy, a pulsed voltage was applied to produce both the DPV signal and ECL signal simultaneously. The ECL and DPV response showed the good linear relationships with the concentration of ENR with the ranges of 0.5 Nm-25 µM and 5 nM-25 µΜ and the detection limits of 0.13 nM and 1.59 nM, respectively.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Pontos Quânticos , Enrofloxacina , Impressão Molecular/métodos , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção , Técnicas Biossensoriais/métodos
16.
Environ Sci Atmos ; 4(2): 265-274, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38371605

RESUMO

Aerosols formed and grown by gas-to-particle processes are a major contributor to smog and haze in megacities, despite the competition between growth and loss rates. Rapid growth rates from ammonium nitrate formation have the potential to sustain particle number in typical urban polluted conditions. This process requires supersaturation of gas-phase ammonia and nitric acid with respect to ammonium nitrate saturation ratios. Urban environments are inhomogeneous. In the troposphere, vertical mixing is fast, and aerosols may experience rapidly changing temperatures. In areas close to sources of pollution, gas-phase concentrations can also be highly variable. In this work we present results from nucleation experiments at -10 °C and 5 °C in the CLOUD chamber at CERN. We verify, using a kinetic model, how long supersaturation is likely to be sustained under urban conditions with temperature and concentration inhomogeneities, and the impact it may have on the particle size distribution. We show that rapid and strong temperature changes of 1 °C min-1 are needed to cause rapid growth of nanoparticles through ammonium nitrate formation. Furthermore, inhomogeneous emissions of ammonia in cities may also cause rapid growth of particles.

17.
Environ Sci Technol ; 58(3): 1601-1614, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38185880

RESUMO

Highly oxygenated organic molecules (HOMs) are a major source of new particles that affect the Earth's climate. HOM production from the oxidation of volatile organic compounds (VOCs) occurs during both the day and night and can lead to new particle formation (NPF). However, NPF involving organic vapors has been reported much more often during the daytime than during nighttime. Here, we show that the nitrate radicals (NO3), which arise predominantly at night, inhibit NPF during the oxidation of monoterpenes based on three lines of observational evidence: NPF experiments in the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN (European Organization for Nuclear Research), radical chemistry experiments using an oxidation flow reactor, and field observations in a wetland that occasionally exhibits nocturnal NPF. Nitrooxy-peroxy radicals formed from NO3 chemistry suppress the production of ultralow-volatility organic compounds (ULVOCs) responsible for biogenic NPF, which are covalently bound peroxy radical (RO2) dimer association products. The ULVOC yield of α-pinene in the presence of NO3 is one-fifth of that resulting from ozone chemistry alone. Even trace amounts of NO3 radicals, at sub-parts per trillion level, suppress the NPF rate by a factor of 4. Ambient observations further confirm that when NO3 chemistry is involved, monoterpene NPF is completely turned off. Our results explain the frequent absence of nocturnal biogenic NPF in monoterpene (α-pinene)-rich environments.


Assuntos
Poluentes Atmosféricos , Monoterpenos Bicíclicos , Ozônio , Compostos Orgânicos Voláteis , Monoterpenos/química , Nitratos/química , Aerossóis/análise , Compostos Orgânicos Voláteis/química
18.
Nat Microbiol ; 9(2): 524-536, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297167

RESUMO

Ammonia-oxidizing microorganisms (AOM) contribute to one of the largest nitrogen fluxes in the global nitrogen budget. Four distinct lineages of AOM: ammonia-oxidizing archaea (AOA), beta- and gamma-proteobacterial ammonia-oxidizing bacteria (ß-AOB and γ-AOB) and complete ammonia oxidizers (comammox), are thought to compete for ammonia as their primary nitrogen substrate. In addition, many AOM species can utilize urea as an alternative energy and nitrogen source through hydrolysis to ammonia. How the coordination of ammonia and urea metabolism in AOM influences their ecology remains poorly understood. Here we use stable isotope tracing, kinetics and transcriptomics experiments to show that representatives of the AOM lineages employ distinct regulatory strategies for ammonia or urea utilization, thereby minimizing direct substrate competition. The tested AOA and comammox species preferentially used ammonia over urea, while ß-AOB favoured urea utilization, repressed ammonia transport in the presence of urea and showed higher affinity for urea than for ammonia. Characterized γ-AOB co-utilized both substrates. These results reveal contrasting niche adaptation and coexistence patterns among the major AOM lineages.


Assuntos
Archaea , Bactérias , Archaea/metabolismo , Bactérias/metabolismo , Amônia/metabolismo , Nitrogênio/metabolismo , Oxirredução , Nitrificação , Filogenia , Microbiologia do Solo , Ureia/metabolismo
19.
Cytokine ; 176: 156508, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38266461

RESUMO

PURPOSE: This study aimed to investigate the expression of fibroblast growth factor 23 (FGF23) in pregnant women with preeclampsia and elucidate its role in promoting placental angiogenesis through the ERK1/2-EGR-1 signaling pathway. METHODS: Serum FGF23 levels were measured by ELISA in healthy pregnant women and patients with preeclampsia during the first, second, and third trimesters of pregnancy. Wound healing, Transwell, and tube formation assays were performed to investigate the effects of FGF23 on cell migration, invasion and tube formation. The expression of vascular endothelial growth factor A (VEGF-A) and its upstream signaling molecules, p-ERK, and EGR-1, in placental tissues was detected by RT-qPCR and western blotting. Additionally, the effect of FGF23 on VEGF-A, p-ERK, and EGR-1 expression was further explored in vitro. RESULTS: Serum FGF23 levels increased with gestational age. During the third trimester, the control group exhibited a more pronounced increase in FGF23 levels than the preeclampsia group. Administering exogenous FGF23 promoted trophoblast cell migration, invasion and enhanced tube formation in vascular endothelial cells. The expression levels of VEGF-A, p-ERK, and EGR-1 in the placental tissues were significantly lower in the preeclampsia group than in the control group. In vitro experiments confirmed that FGF23 up-regulated VEGF-A expression through the p-ERK/EGR-1 signaling pathway. CONCLUSION: The serum level of FGF23 decreased in pregnant women with preeclampsia, inhibiting the ERK1/2-EGR-1 pathway and resulting in decreased expression of VEGF-A, thereby inhibiting placental angiogenesis. This could be a potential mechanism involved in the progression of preeclampsia.


Assuntos
Pré-Eclâmpsia , Fator A de Crescimento do Endotélio Vascular , Feminino , Humanos , Gravidez , Angiogênese , Células Endoteliais/metabolismo , Sistema de Sinalização das MAP Quinases , Placenta/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
medRxiv ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37961373

RESUMO

Background: Prior studies using the ADSP data examined variants within presenilin-2 ( PSEN2 ), presenilin-1 ( PSEN1 ), and amyloid precursor protein ( APP ) genes. However, previously-reported clinically-relevant variants and other predicted damaging missense (DM) variants have not been characterized in a newer release of the Alzheimer's Disease Sequencing Project (ADSP). Objective: To characterize previously-reported clinically-relevant variants and DM variants in PSEN2, PSEN1, APP within the participants from the ADSP. Methods: We identified rare variants (MAF <1%) previously-reported in PSEN2 , PSEN1, and APP in the available ADSP sample of 14,641 individuals with whole genome sequencing and 16,849 individuals with whole exome sequencing available for research-use (N total = 31,490). We additionally curated variants in these three genes from ClinVar, OMIM, and Alzforum and report carriers of variants in clinical databases as well as predicted DM variants in these genes. Results: We detected 31 previously-reported clinically-relevant variants with alternate alleles observed within the ADSP: 4 variants in PSEN2 , 25 in PSEN1 , and 2 in APP . The overall variant carrier rate for the 31 clinically-relevant variants in the ADSP was 0.3%. We observed that 79.5% of the variant carriers were cases compared to 3.9% were controls. In those with AD, the mean age of onset of AD among carriers of these clinically-relevant variants was 19.6 ± 1.4 years earlier compared with non-carriers (p-value=7.8×10 -57 ). Conclusion: A small proportion of individuals in the ADSP are carriers of a previously-reported clinically-relevant variant allele for AD and these participants have significantly earlier age of AD onset compared to non-carriers.

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