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1.
NPJ Clim Atmos Sci ; 7(1): 215, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39281887

RESUMEN

During summer, ammonia emissions in Southeast Asia influence air pollution and cloud formation. Convective transport by the South Asian monsoon carries these pollutant air masses into the upper troposphere and lower stratosphere (UTLS), where they accumulate under anticyclonic flow conditions. This air mass accumulation is thought to contribute to particle formation and the development of the Asian Tropopause Aerosol Layer (ATAL). Despite the known influence of ammonia and particulate ammonium on air pollution, a comprehensive understanding of the ATAL is lacking. In this modelling study, the influence of ammonia on particle formation is assessed with emphasis on the ATAL. We use the EMAC chemistry-climate model, incorporating new particle formation parameterisations derived from experiments at the CERN CLOUD chamber. Our diurnal cycle analysis confirms that new particle formation mainly occurs during daylight, with a 10-fold enhancement in rate. This increase is prominent in the South Asian monsoon UTLS, where deep convection introduces high ammonia levels from the boundary layer, compared to a baseline scenario without ammonia. Our model simulations reveal that this ammonia-driven particle formation and growth contributes to an increase of up to 80% in cloud condensation nuclei (CCN) concentrations at cloud-forming heights in the South Asian monsoon region. We find that ammonia profoundly influences the aerosol mass and composition in the ATAL through particle growth, as indicated by an order of magnitude increase in nitrate levels linked to ammonia emissions. However, the effect of ammonia-driven new particle formation on aerosol mass in the ATAL is relatively small. Ammonia emissions enhance the regional aerosol optical depth (AOD) for shortwave solar radiation by up to 70%. We conclude that ammonia has a pronounced effect on the ATAL development, composition, the regional AOD, and CCN concentrations.

2.
Environ Sci Atmos ; 4(7): 740-753, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39006766

RESUMEN

Isoprene affects new particle formation rates in environments and experiments also containing monoterpenes. For the most part, isoprene reduces particle formation rates, but the reason is debated. It is proposed that due to its fast reaction with OH, isoprene may compete with larger monoterpenes for oxidants. However, by forming a large amount of peroxy-radicals (RO2), isoprene may also interfere with the formation of the nucleating species compared to a purely monoterpene system. We explore the RO2 cross reactions between monoterpene and isoprene oxidation products using the radical Volatility Basis Set (radical-VBS), a simplified reaction mechanism, comparing with observations from the CLOUD experiment at CERN. We find that isoprene interferes with covalently bound C20 dimers formed in the pure monoterpene system and consequently reduces the yields of the lowest volatility (Ultra Low Volatility Organic Carbon, ULVOC) VBS products. This in turn reduces nucleation rates, while having less of an effect on subsequent growth rates.

3.
Environ Sci Atmos ; 4(5): 531-546, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38764888

RESUMEN

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.

4.
PeerJ ; 12: e16975, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38406276

RESUMEN

Background: The coexistence of diabetes mellitus (DM) and atherosclerosis (AS) is widespread, although the explicit metabolism and metabolism-associated molecular patterns (MAMPs) responsible for the correlation are still unclear. Methods: Twenty-four genetically wild-type male Ba-Ma mini pigs were randomly divided into five groups distinguished by different combinations of 90 mg/kg streptozotocin (STZ) intravenous injection and high-cholesterol/lipid (HC) or high-lipid (HL) diet feeding for 9 months in total. Pigs in the STZ+HC and STZ+HL groups were injected with STZ first and then fed the HC or HL diet for 9 months. In contrast, pigs in the HC+STZ and HL+STZ groups were fed the HC or HL diet for 9 months and injected with STZ at 3 months. The controls were only fed a regular diet for 9 months. The blood glucose and abdominal aortic plaque observed through oil red O staining were used as evaluation indicators for successful modelling of DM and AS. A microarray gene expression analysis of all subjects was performed. Results: Atherosclerotic lesions were observed only in the HC+STZ and STZ+HC groups. A total of 103 differentially expressed genes (DEGs) were identified as common between them. The most significantly enriched pathways of 103 common DEGs were influenza A, hepatitis C, and measles. The global and internal protein-protein interaction (PPI) networks of the 103 common DEGs consisted of 648 and 14 nodes, respectively. The top 10 hub proteins, namely, ISG15, IRG6, IRF7, IFIT3, MX1, UBE2L6, DDX58, IFIT2, USP18, and IFI44L, drive aspects of DM and AS. MX1 and UBE2L6 were the intersection of internal and global PPI networks. The expression of MX1 and UBE2L6 was 507.22 ± 342.56 and 96.99 ± 49.92 in the HC+STZ group, respectively, which was significantly higher than others and may be linked to the severity of hyperglycaemia-related atherosclerosis. Further PPI network analysis of calcium/micronutrients, including MX1 and UBE2L6, consisted of 58 and 18 nodes, respectively. The most significantly enriched KEGG pathways were glutathione metabolism, pyrimidine metabolism, purine metabolism, and metabolic pathways. Conclusions: The global and internal PPI network of the 103 common DEGs consisted of 648 and 14 nodes, respectively. The intersection of the nodes of internal and global PPI networks was MX1 and UBE2L6, suggesting their key role in the comorbidity mechanism of DM and AS. This inference was partly verified by the overexpression of MX1 and UBE2L6 in the HC+STZ group but not others. Further calcium- and micronutrient-related enriched KEGG pathway analysis supported that MX1 and UBE2L6 may affect the inflammatory response through micronutrient metabolic pathways, conceptually named metaflammation. Collectively, MX1 and UBE2L6 may be potential common biomarkers for DM and AS that may reveal metaflammatory aspects of the pathological process, although proper validation is still needed to determine their contribution to the detailed mechanism.


Asunto(s)
Aterosclerosis , Diabetes Mellitus , Animales , Masculino , Aterosclerosis/genética , Diabetes Mellitus/patología , Lípidos , Micronutrientes , Proteínas de Resistencia a Mixovirus/metabolismo , Estreptozocina , Porcinos , Porcinos Enanos/metabolismo , Enzimas Ubiquitina-Conjugadoras/metabolismo
5.
Environ Sci Atmos ; 4(2): 265-274, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38371605

RESUMEN

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.

6.
Environ Sci Technol ; 58(3): 1601-1614, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38185880

RESUMEN

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.


Asunto(s)
Contaminantes Atmosféricos , Monoterpenos Bicíclicos , Ozono , Compuestos Orgánicos Volátiles , Monoterpenos/química , Nitratos/química , Aerosoles/análisis , Compuestos Orgánicos Volátiles/química
7.
Environ Sci Technol ; 58(1): 649-659, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38131199

RESUMEN

Iodine oxoacids (HIO3 and HIO2)-driven nucleation has been suggested to efficiently contribute to new particle formation (NPF) in marine atmospheres. Abundant atmospheric nucleation precursors may further enhance HIO3-HIO2-driven nucleation through various multicomponent nucleation mechanisms. However, the specific enhancing potential (EP) of different precursors remains largely unknown. Herein, the EP-based screening model of precursors and enhancing mechanism of the precursor with the highest EP on HIO3-HIO2 nucleation were investigated. The formation free energies (ΔG), as critical parameters for evaluating EP, were calculated for the dimers of 63 selected precursors with HIO2. Based on the ΔG values, (1) a quantitative structure-activity relationship model was developed for evaluating ΔG of other precursors and (2) atmospheric concentrations of 63 (precursor)1(HIO2)1 dimer clusters were assessed to identify the precursors with the highest EP for HIO3-HIO2-driven nucleation by combining with earlier results for the nucleation with HIO3 as the partner. Methanesulfonic acid (MSA) was found to be one of the precursors with the highest EP. Finally, we found that MSA can effectively enhance HIO3-HIO2 nucleation at atmospheric conditions by studying larger MSA-HIO3-HIO2 clusters. These results augment our current understanding of HIO3-HIO2 and MSA-driven nucleation and may suggest a larger impact of HIO2 in atmospheric aerosol nucleation.


Asunto(s)
Atmósfera , Clima , Mesilatos
8.
Science ; 382(6676): 1308-1314, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38096284

RESUMEN

The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H2SO4), stabilized by ammonia (NH3). However, in marine and polar regions, NH3 is generally low, and H2SO4 is frequently found together with iodine oxoacids [HIOx, i.e., iodic acid (HIO3) and iodous acid (HIO2)]. In experiments performed with the CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber, we investigated the interplay of H2SO4 and HIOx during atmospheric particle nucleation. We found that HIOx greatly enhances H2SO4(-NH3) nucleation through two different interactions. First, HIO3 strongly binds with H2SO4 in charged clusters so they drive particle nucleation synergistically. Second, HIO2 substitutes for NH3, forming strongly bound H2SO4-HIO2 acid-base pairs in molecular clusters. Global observations imply that HIOx is enhancing H2SO4(-NH3) nucleation rates 10- to 10,000-fold in marine and polar regions.

9.
Sci Adv ; 9(36): eadi5297, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37682996

RESUMEN

Biogenic vapors form new particles in the atmosphere, affecting global climate. The contributions of monoterpenes and isoprene to new particle formation (NPF) have been extensively studied. However, sesquiterpenes have received little attention despite a potentially important role due to their high molecular weight. Via chamber experiments performed under atmospheric conditions, we report biogenic NPF resulting from the oxidation of pure mixtures of ß-caryophyllene, α-pinene, and isoprene, which produces oxygenated compounds over a wide range of volatilities. We find that a class of vapors termed ultralow-volatility organic compounds (ULVOCs) are highly efficient nucleators and quantitatively determine NPF efficiency. When compared with a mixture of isoprene and monoterpene alone, adding only 2% sesquiterpene increases the ULVOC yield and doubles the formation rate. Thus, sesquiterpene emissions need to be included in assessments of global aerosol concentrations in pristine climates where biogenic NPF is expected to be a major source of cloud condensation nuclei.

10.
Nat Commun ; 14(1): 3347, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37291087

RESUMEN

The interaction between nitrogen monoxide (NO) and organic peroxy radicals (RO2) greatly impacts the formation of highly oxygenated organic molecules (HOM), the key precursors of secondary organic aerosols. It has been thought that HOM production can be significantly suppressed by NO even at low concentrations. Here, we perform dedicated experiments focusing on HOM formation from monoterpenes at low NO concentrations (0 - 82 pptv). We demonstrate that such low NO can enhance HOM production by modulating the RO2 loss and favoring the formation of alkoxy radicals that can continue to autoxidize through isomerization. These insights suggest that HOM yields from typical boreal forest emissions can vary between 2.5%-6.5%, and HOM formation will not be completely inhibited even at high NO concentrations. Our findings challenge the notion that NO monotonically reduces HOM yields by extending the knowledge of RO2-NO interactions to the low-NO regime. This represents a major advance towards an accurate assessment of HOM budgets, especially in low-NO environments, which prevails in the pre-industrial atmosphere, pristine areas, and the upper boundary layer.


Asunto(s)
Atmósfera , Óxido Nítrico , Monoterpenos , Oxidación-Reducción , Aerosoles
11.
Environ Sci Technol ; 57(17): 6944-6954, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37083433

RESUMEN

Iodic acid (IA) has recently been recognized as a key driver for new particle formation (NPF) in marine atmospheres. However, the knowledge of which atmospheric vapors can enhance IA-induced NPF remains limited. The unique halogen bond (XB)-forming capacity of IA makes it difficult to evaluate the enhancing potential (EP) of target compounds on IA-induced NPF based on widely studied sulfuric acid systems. Herein, we employed a three-step procedure to evaluate the EP of potential atmospheric nucleation precursors on IA-induced NPF. First, we evaluated the EP of 63 precursors by simulating the formation free energies (ΔG) of the IA-containing dimer clusters. Among all dimer clusters, 44 contained XBs, demonstrating that XBs are frequently formed. Based on the calculated ΔG values, a quantitative structure-activity relationship model was developed for evaluating the EP of other precursors. Second, amines and O/S-atom-containing acids were found to have high EP, with diethylamine (DEA) yielding the highest potential to enhance IA-induced nucleation by combining both the calculated ΔG and atmospheric concentration of considered 63 precursors. Finally, by studying larger (IA)1-3(DEA)1-3 clusters, we found that the IA-DEA system with merely 0.1 ppt (2.5×106 cm-3) DEA yields comparable nucleation rates to that of the IA-iodous acid system.


Asunto(s)
Atmósfera , Yodatos , Atmósfera/química , Aminas , Gases
12.
BMC Nephrol ; 24(1): 51, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-36899322

RESUMEN

BACKGROUND: Bevacizumab is a monoclonal antibody drug targeting Vascular Endothelial Growth Factor (VEGF), which binds to VEGF receptors to inhibit vascular endothelial cell proliferation and angiogenesis, thus inhibiting tumorigenesis. Pembrolizumab is a monoclonal antibody that can bind to the programmed death-1 (PD-1) receptor, which can block the binding of the PD-1 receptor to its ligands PD-L1 and PD-L2, and release PD-1 pathway-mediated suppression of immune responses. By blocking the activity of PD-1, the purpose of inhibiting tumor growth is achieved. CASE PRESENTATION: We report a severe hematuria of bevacizumab plus pembrolizumab, in a 58-year-old woman with metastatic cervical cancer. After three cycles every three weeks of consolidation chemotherapy (carboplatin, paclitaxel, bevacizumab) and following three cycles consolidation chemotherapy (carboplatin, paclitaxel, bevacizumab, pembrolizumab), the patient presented a worsening state. Manifested as massive gross hematuria with blood clots. After stopping chemotherapy, cefoxitin, tranexamic acid and hemocoagulase atrox therapy was administered resulting in rapid clinical improvement. The patient was a cervical cancer with bladder metastasis that increases the risk of development of hematuria. Inhibition of VEGF, which has anti-apoptotic, anti-inflammatory, and pro-survival influences on endothelial cells, weakens their regenerative capacity and increases expression of proinflammatory genes leading to weakened supporting layers of blood vessels and, hence, to damaged vascular integrity. In our patient, the development of hematuria may result from the anti-VEGF effect of bevacizumab. In addition, pembrolizumab may also cause bleeding, and the mechanism of bleeding caused by pembrolizumab is currently unclear, which may be related to immune mediation. CONCLUSION: To our knowledge, this is the first case reporting on the development of severe hematuria during bevacizumab plus pembrolizumab treatment, which should alert the clinicians in case of bleeding adverse events onset in older patients under bevacizumab plus pembrolizumab therapy.


Asunto(s)
Neoplasias Pulmonares , Neoplasias del Cuello Uterino , Femenino , Humanos , Anciano , Persona de Mediana Edad , Bevacizumab , Carboplatino/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/etiología , Factor A de Crecimiento Endotelial Vascular , Hematuria/etiología , Células Endoteliales , Receptor de Muerte Celular Programada 1 , Paclitaxel/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico
13.
Nat Commun ; 14(1): 1769, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36997509

RESUMEN

Chlorine radicals are strong atmospheric oxidants known to play an important role in the depletion of surface ozone and the degradation of methane in the Arctic troposphere. Initial oxidation processes of chlorine produce chlorine oxides, and it has been speculated that the final oxidation steps lead to the formation of chloric (HClO3) and perchloric (HClO4) acids, although these two species have not been detected in the atmosphere. Here, we present atmospheric observations of gas-phase HClO3 and HClO4. Significant levels of HClO3 were observed during springtime at Greenland (Villum Research Station), Ny-Ålesund research station and over the central Arctic Ocean, on-board research vessel Polarstern during the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC) campaign, with estimated concentrations up to 7 × 106 molecule cm-3. The increase in HClO3, concomitantly with that in HClO4, was linked to the increase in bromine levels. These observations indicated that bromine chemistry enhances the formation of OClO, which is subsequently oxidized into HClO3 and HClO4 by hydroxyl radicals. HClO3 and HClO4 are not photoactive and therefore their loss through heterogeneous uptake on aerosol and snow surfaces can function as a previously missing atmospheric sink for reactive chlorine, thereby reducing the chlorine-driven oxidation capacity in the Arctic boundary layer. Our study reveals additional chlorine species in the atmosphere, providing further insights into atmospheric chlorine cycling in the polar environment.

14.
Environ Sci Technol ; 57(6): 2297-2309, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36716278

RESUMEN

The mechanistic pathway by which high relative humidity (RH) affects gas-particle partitioning remains poorly understood, although many studies report increased secondary organic aerosol (SOA) yields at high RH. Here, we use real-time, molecular measurements of both the gas and particle phase to provide a mechanistic understanding of the effect of RH on the partitioning of biogenic oxidized organic molecules (from α-pinene and isoprene) at low temperatures (243 and 263 K) at the CLOUD chamber at CERN. We observe increases in SOA mass of 45 and 85% with increasing RH from 10-20 to 60-80% at 243 and 263 K, respectively, and attribute it to the increased partitioning of semi-volatile compounds. At 263 K, we measure an increase of a factor 2-4 in the concentration of C10H16O2-3, while the particle-phase concentrations of low-volatility species, such as C10H16O6-8, remain almost constant. This results in a substantial shift in the chemical composition and volatility distribution toward less oxygenated and more volatile species at higher RH (e.g., at 263 K, O/C ratio = 0.55 and 0.40, at RH = 10 and 80%, respectively). By modeling particle growth using an aerosol growth model, which accounts for kinetic limitations, we can explain the enhancement in the semi-volatile fraction through the complementary effect of decreased compound activity and increased bulk-phase diffusivity. Our results highlight the importance of particle water content as a diluting agent and a plasticizer for organic aerosol growth.


Asunto(s)
Contaminantes Atmosféricos , Monoterpenos , Monoterpenos/química , Humedad , Aerosoles
15.
Cancer Med ; 12(3): 3365-3375, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35871395

RESUMEN

OBJECTIVE: Poly ADP-ribose polymerase inhibitors (PARPis) have significantly improved clinical effects in gynecological oncology. However, PARPis could also induce severe organ system toxicities, including the hematological system. Our study aimed to extensively characterize the hematological toxicities of PARPis based on the real-world data. METHODS: Disproportionality analysis was used to evaluate the association between PARPis and hematotoxicity adverse events. Data were extracted from the US FDA Adverse Event Reporting System (FAERS) database between January 2015 and September 2021. The characteristics of PARPi-associated hematological toxicities, and the onset time and fatality proportion were further analyzed. RESULTS: Out of 24,045 adverse events reports, 4088 hematotoxicity reports (17.00%) were analyzed, with a median age of 64.95 (interquartile range [IQR] 51-71) years. All PARPis were detected with positive safety signals of hematological toxicities in four detection methods. Unexpected significant adverse events such as lymphadenopathy, lymphoedema, and metastases to lymph nodes might also occur. The median time-to-onset was 28 (IQR 10-101) days and the fatality proportion of hematological toxicities with PARPis was 8.76%, with a statistical difference in different PARPis. CONCLUSION: Hematological toxicities caused by PARPis preferred to occur early and might result in serious outcomes. Early identification and response to the PARPi-related hematological toxicities were important and further basic research were needed to confirm the mechanism of results in this study.


Asunto(s)
Inhibidores de Poli(ADP-Ribosa) Polimerasas , Anciano , Humanos , Persona de Mediana Edad , Bases de Datos Factuales , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , Medición de Riesgo , Estados Unidos , United States Food and Drug Administration , Sistemas de Registro de Reacción Adversa a Medicamentos
16.
Nat Chem ; 15(1): 129-135, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36376388

RESUMEN

Iodine is a reactive trace element in atmospheric chemistry that destroys ozone and nucleates particles. Iodine emissions have tripled since 1950 and are projected to keep increasing with rising O3 surface concentrations. Although iodic acid (HIO3) is widespread and forms particles more efficiently than sulfuric acid, its gas-phase formation mechanism remains unresolved. Here, in CLOUD atmospheric simulation chamber experiments that generate iodine radicals at atmospherically relevant rates, we show that iodooxy hypoiodite, IOIO, is efficiently converted into HIO3 via reactions (R1) IOIO + O3 → IOIO4 and (R2) IOIO4 + H2O → HIO3 + HOI + (1)O2. The laboratory-derived reaction rate coefficients are corroborated by theory and shown to explain field observations of daytime HIO3 in the remote lower free troposphere. The mechanism provides a missing link between iodine sources and particle formation. Because particulate iodate is readily reduced, recycling iodine back into the gas phase, our results suggest a catalytic role of iodine in aerosol formation.


Asunto(s)
Yodatos , Yodo , Aerosoles
17.
Front Public Health ; 10: 996179, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36339230

RESUMEN

Background: Semaglutide was approved for treatment of type 2 diabetes mellitus (T2DM) and chronic weight management in obesity or overweight adults. However, real-world data regarding its long-term gastrointestinal safety and tolerability in large sample population are incomplete. We evaluated semaglutide-associated gastrointestinal safety signals by data mining of the FDA pharmacovigilance database. Methods: Reporting odds ratio (ROR) was employed to quantify the signals of semaglutide-related gastrointestinal adverse events (AEs) from 2018 to 2022. Serious and non-serious cases were compared by Mann-Whitney U test or Chi-squared (χ2) test, and signals were prioritized using a rating scale. Results: We identified 5,442 cases of semaglutide-associated gastrointestinal AEs, with 45 signals detected, ranging from a ROR025 of 1.01 (hypoaesthesia oral) to 42.03 (eructation), among which 17 AEs were identified as new and unexpected signals. Patient age (p < 0.001) and body weight (p = 0.006) rather than sex (p = 0.251) might be associated with an increased risk of gastrointestinal AEs severity. Notably, the association between semaglutide and gastrointestinal disorders remained when stratified by age, body weight, sex and reporter type. One strong, 22 moderate and 22 weak clinical priority signals were defined. The median time-to-onset (TTO) for strong clinical priority signal was 23 days, while for moderate and weak, they were 6 and 7 days, respectively. All of the disproportionality signals had early failure type features, suggesting that the risk of gastrointestinal AEs occurrence gradually decreased over time. Conclusion: Our study provided a deeper and broader understanding of semaglutide's gastrointestinal safety profiles, which would help healthcare professionals to mitigate the risk of gastrointestinal AEs in clinical practice.


Asunto(s)
Diabetes Mellitus Tipo 2 , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Adulto , Humanos , Farmacovigilancia , Sistemas de Registro de Reacción Adversa a Medicamentos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Peso Corporal
18.
Front Pharmacol ; 13: 920479, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36204237

RESUMEN

Objective: The purpose of this study was to estimate the cost-effectiveness of osimertinib for the first-line treatment of patients with EGFR-mutated advanced non-small-cell lung cancer (NSCLC) from the perspective of the Chinese healthcare system. Methods: A Markov model was developed to simulate the outcomes and direct medical costs of osimertinib or standard EGFR-TKI in the first-line treatment of patients with previously untreated EGFR-mutated advanced NSCLC. Individual patient survival data were extracted from the FLAURA randomized clinical trial. Clinical costs and utilities' input estimates were collected from the local hospital and available literature reports. The quality-adjusted life-year (QALY), incremental cost-effectiveness ratio (ICER), incremental net monetary benefit (INMB), and incremental net health benefit (INHB) were calculated for the two treatment strategies over a 10-year lifetime horizon. In addition, one-way sensitivity analysis, probabilistic sensitivity analysis, and subgroup analysis were performed to test the robustness of the model. Results: On baseline analysis, osimertinib achieved additional 0.39 QALYs and $15,443.78 incremental costs compared with standard EGFR-TKI (gefitinib or erlotinib), which resulted in the ICER of $39,369.53/QALY. The INMB was -$755.11, and the INHB was -0.02 QALYs at a WTP threshold of $37,663.26/QALY in China. The one-way sensitivity analysis showed that the utility of PFS had the strongest association with the ICER. Osimertinib had approximately 46.4% probability of being cost-effective at the WTP threshold of $37,663.26/QALY. Conclusion: First-line osimertinib therapy might not be cost-effective in China for patients with EGFR-mutated advanced NSCLC compared with standard EGFR-TKI based on its current marketed price. A significantly more favorable cost-effectiveness could be achieved when the price of osimertinib was reduced by 5%.

19.
Front Pharmacol ; 13: 990241, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36147351

RESUMEN

Objective: The objective of this study was to scientifically and systematically explore the association between fluoroquinolones (ciprofloxacin, levofloxacin, and moxifloxacin) and tendonitis and tendon rupture through the Food and Drug Administration Adverse Event Reporting System (FAERS) database. Methods: Disproportionality analysis was used to quantify the signals of fluoroquinolone-associated suspected tendonitis and tendon rupture based on the FAERS data from January 2016 to March 2021. Clinical characteristics, the onset time, oral and intravenous administrations, and the serious outcomes of fluoroquinolone-associated tendonitis and tendon rupture were further analyzed. Results: Out of 35,667 fluoroquinolone-associated adverse events recorded in the FAERS database during the study period, 1,771 tendonitis and 1,018 tendon ruptures induced by fluoroquinolones as the suspected drug were analyzed, with a median age of 49.88-63.87 years. All three fluoroquinolones detected positive signals of tendonitis and tendon rupture in the four methods. Ciprofloxacin had the strongest statistical association with tendonitis with the highest positive signal values (ROR 98.50, PRR 93.25, IC 6.15, and EBGM 76.80), while levofloxacin showed the strongest statistical association with tendon rupture (ROR 76.38, PRR 73.75, IC 5.84, and EBGM 63.89). Compared with ciprofloxacin and levofloxacin, moxifloxacin was relatively weakly associated with tendonitis and tendon rupture. Oral fluoroquinolone-induced tendonitis and tendon rupture had a stronger signal strength than intravenous administration. The majority of fluroquinolone-related suspected tendonitis and tendon rupture tended to occur within a few days or one month. As for the disability rate of tendonitis, ciprofloxacin counted the highest (n = 461, 50.94%), with moxifloxacin the lowest (n = 20, 29.41%). Conclusion: Fluoroquinolone-induced tendonitis and tendon rupture tended to occur early and might result in serious outcomes. Our study provided valuable references for early identification of the risk of fluoroquinolone-induced tendonitis and tendon rupture.

20.
Environ Sci Technol ; 56(19): 13931-13944, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36137236

RESUMEN

Dimethyl sulfide (DMS) influences climate via cloud condensation nuclei (CCN) formation resulting from its oxidation products (mainly methanesulfonic acid, MSA, and sulfuric acid, H2SO4). Despite their importance, accurate prediction of MSA and H2SO4 from DMS oxidation remains challenging. With comprehensive experiments carried out in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at CERN, we show that decreasing the temperature from +25 to -10 °C enhances the gas-phase MSA production by an order of magnitude from OH-initiated DMS oxidation, while H2SO4 production is modestly affected. This leads to a gas-phase H2SO4-to-MSA ratio (H2SO4/MSA) smaller than one at low temperatures, consistent with field observations in polar regions. With an updated DMS oxidation mechanism, we find that methanesulfinic acid, CH3S(O)OH, MSIA, forms large amounts of MSA. Overall, our results reveal that MSA yields are a factor of 2-10 higher than those predicted by the widely used Master Chemical Mechanism (MCMv3.3.1), and the NOx effect is less significant than that of temperature. Our updated mechanism explains the high MSA production rates observed in field observations, especially at low temperatures, thus, substantiating the greater importance of MSA in the natural sulfur cycle and natural CCN formation. Our mechanism will improve the interpretation of present-day and historical gas-phase H2SO4/MSA measurements.

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