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1.
Cell ; 186(3): 591-606.e23, 2023 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-36669483

RESUMEN

Dysregulation of the immune system is a cardinal feature of opioid addiction. Here, we characterize the landscape of peripheral immune cells from patients with opioid use disorder and from healthy controls. Opioid-associated blood exhibited an abnormal distribution of immune cells characterized by a significant expansion of fragile-like regulatory T cells (Tregs), which was positively correlated with the withdrawal score. Analogously, opioid-treated mice also showed enhanced Treg-derived interferon-γ (IFN-γ) expression. IFN-γ signaling reshaped synaptic morphology in nucleus accumbens (NAc) neurons, modulating subsequent withdrawal symptoms. We demonstrate that opioids increase the expression of neuron-derived C-C motif chemokine ligand 2 (Ccl2) and disrupted blood-brain barrier (BBB) integrity through the downregulation of astrocyte-derived fatty-acid-binding protein 7 (Fabp7), which both triggered peripheral Treg infiltration into NAc. Our study demonstrates that opioids drive the expansion of fragile-like Tregs and favor peripheral Treg diapedesis across the BBB, which leads to IFN-γ-mediated synaptic instability and subsequent withdrawal symptoms.


Asunto(s)
Interferón gamma , Trastornos Relacionados con Opioides , Síndrome de Abstinencia a Sustancias , Linfocitos T Reguladores , Animales , Ratones , Analgésicos Opioides/administración & dosificación , Interferón gamma/metabolismo , Trastornos Relacionados con Opioides/metabolismo , Trastornos Relacionados con Opioides/patología
2.
Nature ; 590(7846): 433-437, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33568814

RESUMEN

Emissions of ozone-depleting substances, including trichlorofluoromethane (CFC-11), have decreased since the mid-1980s in response to the Montreal Protocol1,2. In recent years, an unexpected increase in CFC-11 emissions beginning in 2013 has been reported, with much of the global rise attributed to emissions from eastern China3,4. Here we use high-frequency atmospheric mole fraction observations from Gosan, South Korea and Hateruma, Japan, together with atmospheric chemical transport-model simulations, to investigate regional CFC-11 emissions from eastern China. We find that CFC-11 emissions returned to pre-2013 levels in 2019 (5.0 ± 1.0 gigagrams per year in 2019, compared to 7.2 ± 1.5 gigagrams per year for 2008-2012, ±1 standard deviation), decreasing by 10 ± 3 gigagrams per year since 2014-2017. Furthermore, we find that in this region, carbon tetrachloride (CCl4) and dichlorodifluoromethane (CFC-12) emissions-potentially associated with CFC-11 production-were higher than expected after 2013 and then declined one to two years before the CFC-11 emissions reduction. This suggests that CFC-11 production occurred in eastern China after the mandated global phase-out, and that there was a subsequent decline in production during 2017-2018. We estimate that the amount of the CFC-11 bank (the amount of CFC-11 produced, but not yet emitted) in eastern China is up to 112 gigagrams larger in 2019 compared to pre-2013 levels, probably as a result of recent production. Nevertheless, it seems that any substantial delay in ozone-layer recovery has been avoided, perhaps owing to timely reporting3,4 and subsequent action by industry and government in China5,6.

3.
Proc Natl Acad Sci U S A ; 121(12): e2318716121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38483991

RESUMEN

Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.

4.
Nano Lett ; 24(25): 7637-7644, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38874010

RESUMEN

Revealing the effect of surface structure changes on the electrocatalytic performance is beneficial to the development of highly efficient catalysts. However, precise regulation of the catalyst surface at the atomic level remains challenging. Here, we present a continuous strain regulation of palladium (Pd) on gold (Au) via a mechanically controllable surface strain (MCSS) setup. It is found that the structural changes induced by the strain setup can accelerate electron transfer at the solid-liquid interface, thus achieving a significantly improved performance toward hydrogen evolution reaction (HER). In situ X-ray diffraction (XRD) experiments further confirm that the enhanced activity is attributed to the increased interplanar spacing resulting from the applied strain. Theoretical calculations reveal that the tensile strain modulates the electronic structure of the Pd active sites and facilitates the desorption of the hydrogen intermediates. This work provides an effective approach for revealing the relationships between the electrocatalyst surface structure and catalytic activity.

5.
Immunol Cell Biol ; 102(7): 570-577, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38710590

RESUMEN

The γδ T cells are a subpopulation of T cells that are abundantly found in the skin and mucous membranes. Their reactivity to self-antigens and ability to secrete various cytokines make them a key component in psoriasis development. Although the correlation between the immune repertoire (IR) of γδ T-cell receptors and the occurrence and severity of psoriasis remains incompletely explored, high-throughput sequencing of γδ T cells has led to a deeper understanding of IR in psoriasis. This study investigated the differences between γδ T cells in patients with psoriasis and healthy controls. The γδ T cells were identified via immunofluorescence staining and a correlation analysis was performed according to the psoriasis area and severity index (PASI) scores. The IR sequencing method was used to detect IR in the γδ T-cell receptors. The findings demonstrated more skin γδ T cells in patients with psoriasis, which were positively correlated with the PASI score. There were subtle differences in most variable (V), diversity (D) and joining (J) gene segments and VJ/VDJ combination segments between patients with psoriasis and healthy controls. However, a higher diversity of complementarity-determining region 3 (CDR3) was observed in patients with psoriasis. In summary, the IR of skin γδ T cells was significantly altered in patients with psoriasis, and the diversity in the cell's CDR3 population is a promising biomarker for assessment of psoriasis severity.


Asunto(s)
Regiones Determinantes de Complementariedad , Psoriasis , Receptores de Antígenos de Linfocitos T gamma-delta , Humanos , Psoriasis/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Regiones Determinantes de Complementariedad/genética , Piel/inmunología , Piel/patología , Índice de Severidad de la Enfermedad , Linfocitos T/inmunología , Linfocitos T/metabolismo , Estudios de Casos y Controles
6.
Small ; 20(8): e2305607, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37817357

RESUMEN

The molecule-electrode coupling plays an essential role in photoresponsive devices with photochromic molecules, and the strong coupling between the molecule and the conventional electrodes leads to/ the quenching effect and limits the reversibility of molecular photoswitches. In this work, we developed a strategy of using transition metal dichalcogenides (TMDCs) electrodes to fabricate the thiol azobenzene (TAB) self-assembled monolayers (SAMs) junctions with the eutectic gallium-indium (EGaIn) technique. The current-voltage characteristics of the EGaIn/GaOx //TAB/TMDCs photoswitches showed an almost 100% reversible photoswitching behavior, which increased by ∼28% compared to EGaIn/GaOx //TAB/AuTS photoswitches. Density functional theory (DFT) calculations showed the coupling strength of the TAB-TMDCs electrode decreased by 42% compared to that of the TAB-AuTS electrode, giving rise to improved reversibility. our work demonstrated the feasibility of 2D TMDCs for fabricating SAMs-based photoswitches with unprecedentedly high reversibility.

7.
J Pharmacol Exp Ther ; 391(1): 39-50, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39095206

RESUMEN

Warfarin, with its narrow therapeutic range, requires the understanding of various influencing factors for personalized medication. Vascular senescence, marked by vascular stiffening and endothelial dysfunction, has an unclear effect on the efficacy and safety of warfarin. Based on previous studies, we hypothesized that vascular senescence increases the risk of bleeding during warfarin therapy. This study aimed to explore these effects using animal models and clinical cohorts. We established rat models of vascular senescence and calcification using d-galactose, vitamin D, and nicotine. After validating the models, we examined changes in the international normalized ratio (INR) at fixed warfarin doses (0.20 and 0.35 mg/kg). We found that vascular senescence caused significantly elevated INR values and increased bleeding risk. In the prospective clinical cohort study (NCT06428110), hospitalized warfarin patients with standard dose adjustments were divided into vascular senescence and control groups based on ultrasound and computed tomography diagnosis. Using propensity score matching to exclude the influence of confounding factors, we found that the vascular senescence group had lower steady-state warfarin doses and larger dose adjustments, with a higher probability of INR exceeding the therapeutic range. The vascular senescence group tended to experience more bleeding or thromboembolic/ischemic events during 1 year of follow-up, while there was no statistical difference. In conclusion, vascular senescence leads to unstable INR values and increases higher bleeding risk during warfarin therapy, highlighting the importance of considering vascular senescence in future precision warfarin therapies. SIGNIFICANCE STATEMENT: Many factors influence warfarin efficacy; however, the effect of vascular senescence remains unclear. This study aimed to investigate the effects of vascular senescence on the efficacy and safety of warfarin. Through both rat models and clinical cohort studies, our findings indicated that vascular senescence may compromise the stability of warfarin, presenting challenges in maintaining its efficacy and safety.


Asunto(s)
Anticoagulantes , Warfarina , Anciano , Animales , Femenino , Humanos , Masculino , Ratas , Anticoagulantes/farmacología , Anticoagulantes/efectos adversos , Anticoagulantes/administración & dosificación , Vasos Sanguíneos/efectos de los fármacos , Hemorragia/inducido químicamente , Relación Normalizada Internacional , Estudios Prospectivos , Ratas Sprague-Dawley , Resultado del Tratamiento , Warfarina/efectos adversos , Warfarina/farmacología , Warfarina/administración & dosificación
8.
Plant Physiol ; 191(4): 2301-2315, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36660817

RESUMEN

Drought stress (DS) challenges sustainable agriculture production by limiting crop growth and development. The objective of the study was to evaluate the effect of melatonin-priming on enzymatic and non-enzymatic antioxidant defense mechanisms and its relation with leaf ultrastructure and stomatal traits in maize (Zea mays L) seedlings under DS (PEG-6000). DS drastically decreased seed germination, plant growth, and leaf chlorophyll content due to excessive reactive oxygen species (ROS) production. Melatonin-priming significantly (P < 0.05) increased seed germination, root length, shoot length, fresh seedling weight, proline content, total soluble protein content, sugar content, chlorophyll content, and stomatal aperture size by 101%, 30%, 133%, 51%, 22%, 59%, 54%, 20%, and 424%, compared to no priming (NP) under DS, respectively. Similarly, priming improved leaf ultrastructure and reduced the amount of chlorophyll loss and oxidative damage in maize seedlings. Melatonin seed priming with 500 µM melatonin (M2) greatly increased superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione, and ascorbate (AsA) activity, by 65%, 63%, 94%, 41%, and 55% compared to NP under DS and by 0.26%, 8%, 33%, 42%, and 15% under no-stress (NS), respectively. Melatonin-priming also reduced malondialdehyde content, electrolyte leakage, hydrogen peroxide (H2O2) content, and superoxide anion (O2-) content by 26%, 31%, 31%, and 33% compared to NP under DS and by 8%, 18%, 10%, and 11% under NS, respectively. In response to DS, melatonin-priming also stabilized the chloroplast structure, sustained cell expansion, protected cell walls, and greatly improved stomatal traits, including stomatal number, length, and width. Our results suggest that melatonin-priming improves drought tolerance in maize seedlings by alleviating the negative effect of ROS.


Asunto(s)
Antioxidantes , Melatonina , Antioxidantes/metabolismo , Plantones/metabolismo , Melatonina/farmacología , Melatonina/metabolismo , Zea mays/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Resistencia a la Sequía , Peróxido de Hidrógeno/metabolismo , Clorofila/metabolismo
9.
Transgenic Res ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158822

RESUMEN

The application of rapidly growing CRISPR toolboxes and methods has great potential to transform biomedical research. Here, we provide a snapshot of up-to-date CRISPR toolboxes, then critically discuss the promises and hurdles associated with CRISPR-based nuclear genome editing, epigenome editing, and mitochondrial editing. The technical challenges and key solutions to realize epigenome editing in vivo, in vivo base editing and prime editing, mitochondrial editing in complex tissues and animals, and CRISPR-associated transposases and integrases in targeted genomic integration of very large DNA payloads are discussed. Lastly, we discuss the latest situation of the CRISPR/Cas9 clinical trials and provide perspectives on CRISPR-based gene therapy. Apart from technical shortcomings, ethical and societal considerations for CRISPR applications in human therapeutics and research are extensively highlighted.

10.
Langmuir ; 40(21): 10908-10915, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38739034

RESUMEN

Band 3, or anion exchanger 1 (AE1), is one of the indispensable transmembrane proteins involved in the effective respiratory process of the human body and is primarily responsible for the exchange of bicarbonate and chloride anions across the plasma membrane of erythrocyte. However, the molecular mechanism of ion transport of Band 3 is not completely understood, yet. In this work, we systematically investigate the key binding sites of bicarbonate ions in Band 3 and the impact of cholesterol (CHOL) in lipid bilayers on bicarbonate ion binding using all-atom molecular dynamics (MD) simulations. We examine the dynamics of interactions of bicarbonate ions with Band 3 in the microsecond time scale and calculate the binding free energy of the anion in Band 3. The results indicate that the residue R730 of Band 3 is the most probable binding site for bicarbonate ions. CHOL enhances the bicarbonate ion binding by influencing the conformational stability of Band 3 and compressing the volume of the Band 3 cavity. These findings provide some insights into the bicarbonate ion binding in Band 3 and are helpful for understanding the anion exchange of Band 3.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito , Bicarbonatos , Colesterol , Simulación de Dinámica Molecular , Proteína 1 de Intercambio de Anión de Eritrocito/química , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Bicarbonatos/química , Bicarbonatos/metabolismo , Colesterol/química , Colesterol/metabolismo , Humanos , Sitios de Unión , Unión Proteica , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo
11.
Liver Int ; 44(6): 1435-1447, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38483145

RESUMEN

BACKGROUND AND AIMS: The use of corticosteroids in chronic drug-induced liver injury (DILI) is an important issue. Our previous randomized controlled trial showed that patients with chronic DILI benefited from a 48-week steroid stepwise reduction (SSR) regimen. However, it remains unclear whether a shorter course of therapy can achieve similar efficacy. In this study, we aimed to assess whether a 36-week SSR can achieve efficacy similar to that of 48-week SSR. METHODS: A randomized open-label trial was performed. Eligible patients were randomly assigned to the 36- or 48-week (1:1) SSR group. Liver biopsies were performed at baseline and at the end of treatment. The primary outcome was the proportion of patients with relapse rate (RR). The secondary outcomes were improvement in liver histology and safety. RESULTS: Of the 90 participants enrolled, 84 (87.5%) completed the trial, and 62 patients (68.9%) were women. Hepatocellular damage was observed in 53.4% of the cohort. The RR was 7.1% in the 36-week SSR group but 4.8% in the 48-week SSR group, as determined by per-protocol set analysis (p = 1.000). Significant histological improvements in histological activity (93.1% vs. 92.9%, p = 1.000) and fibrosis (41.4% vs. 46.4%, p = .701) were observed in both the groups. Biochemical normalization time did not differ between the two groups. No severe adverse events were observed. CONCLUSIONS: Both the 36- and 48-week SSR regimens demonstrated similar biochemical response and histological improvements with good safety, supporting 36-week SSR as a preferable therapeutic choice (ClinicalTrials.gov, NCT03266146).


Asunto(s)
Hígado , Humanos , Femenino , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto , Hígado/patología , Hígado/efectos de los fármacos , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/etiología , Resultado del Tratamiento , Glucocorticoides/administración & dosificación , Glucocorticoides/efectos adversos , Recurrencia , Anciano , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Esquema de Medicación
12.
Inflamm Res ; 73(3): 345-362, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38157008

RESUMEN

OBJECTIVES: Colitis is a global disease usually accompanied by intestinal epithelial damage and intestinal inflammation, and an increasing number of studies have found natural products to be highly effective in treating colitis. Anemoside B4 (AB4), an abundant saponin isolated from Pulsatilla chinensis (Bunge), which was found to have strong anti-inflammatory activity. However, the exact molecular mechanisms and direct targets of AB4 in the treatment of colitis remain to be discovered. METHODS: The anti-inflammatory activities of AB4 were verified in LPS-induced cell models and 2, 4, 6-trinitrobenzene sulfonic (TNBS) or dextran sulfate sodium (DSS)-induced colitis mice and rat models. The molecular target of AB4 was identified by affinity chromatography analysis using chemical probes derived from AB4. Experiments including proteomics, molecular docking, biotin pull-down, surface plasmon resonance (SPR), and cellular thermal shift assay (CETSA) were used to confirm the binding of AB4 to its molecular target. Overexpression of pyruvate carboxylase (PC) and PC agonist were used to study the effects of PC on the anti-inflammatory and metabolic regulation of AB4 in vitro and in vivo. RESULTS: AB4 not only significantly inhibited LPS-induced NF-κB activation and increased ROS levels in THP-1 cells, but also suppressed TNBS/DSS-induced colonic inflammation in mice and rats. The molecular target of AB4 was identified as PC, a key enzyme related to fatty acid, amino acid and tricarboxylic acid (TCA) cycle. We next demonstrated that AB4 specifically bound to the His879 site of PC and altered the protein's spatial conformation, thereby affecting the enzymatic activity of PC. LPS activated NF-κB pathway and increased PC activity, which caused metabolic reprogramming, while AB4 reversed this phenomenon by inhibiting the PC activity. In vivo studies showed that diisopropylamine dichloroacetate (DADA), a PC agonist, eliminated the therapeutic effects of AB4 by changing the metabolic rearrangement of intestinal tissues in colitis mice. CONCLUSION: We identified PC as a direct cellular target of AB4 in the modulation of inflammation, especially colitis. Moreover, PC/pyruvate metabolism/NF-κB is crucial for LPS-driven inflammation and oxidative stress. These findings shed more light on the possibilities of PC as a potential new target for treating colitis.


Asunto(s)
Colitis , Saponinas , Ratas , Ratones , Animales , Piruvato Carboxilasa/metabolismo , FN-kappa B/metabolismo , Lipopolisacáridos/farmacología , Simulación del Acoplamiento Molecular , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Inflamación/metabolismo , Saponinas/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Macrófagos/metabolismo , Sulfato de Dextran/efectos adversos , Sulfato de Dextran/metabolismo , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
13.
Inorg Chem ; 63(38): 17672-17680, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39259024

RESUMEN

Cluster-assembled nanowires provide a unique strategy for the preparation of high-performance nanostructures. However, existing preparations are limited by complex processes and harsh reaction conditions. Here, Ag+ ions were utilized as a novel structure-directing agent to generate the self-assembly of Pt clusters to form ultrafine nanowires with a diameter of less than 5 nm. Electrospray ionization mass spectrometry (ESI-MS) and extended X-ray absorption fine structure (EXAFS) characterizations demonstrated that every Ag+ bridged two [Pt3(CO)3(µ2-CO)3]n2- clusters through coordination and formed a sandwich-like structure of [Pt3(CO)3(µ2-CO)3]nAg[Pt3(CO)3(µ2-CO)3]m3-. As a result, multiple sandwich-like structures of [Pt3(CO)3(µ2-CO)3]nAg[Pt3(CO)3(µ2-CO)3]m3- were established by Ag+ to form Pt nanowire superstructures {[Pt3(CO)6]nAg[Pt3(CO)6]mAg[Pt3(CO)6]x}∞ (abbreviated as Ag-Pt NWS). Our results demonstrate that the Pt nanowire superstructures showed promising cocatalytic performance for photocatalytic H2 production with the involvement of Ag+, which promises a desirable way to develop advanced functional nanomaterials.

14.
Environ Res ; : 120284, 2024 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-39491604

RESUMEN

The adsorption and removal of heavy metal ions Cr(VI) is of great significance for human health and ecological environment. Here, a ultrafast and high efficient adsorbent for Cr(VI) was developed based on cetyltrimethylammonium bromide (CTAB)-modified zein nanoparticles (C-ZNPs). In comparison to pristine zein nanoparticles (ZNPs) (11.199 m2·g-1), the surfactant-modified C-ZNPs exhibited larger specific surface area (17.002 m2·g-1). Moreover, C-ZNPs had superior dispersion and more positive charge distribution, which contributed to the improvement for adsorption performance. The results showed that the saturated adsorption of Cr(VI) was reached up to 192.27 mg/g using the C-ZNPs nanosorbent at T = 298 K, pH = 4, t = 10s, and C0 = 125 mg/L. The removal rate was significantly faster than that reported natural polymer-based adsorbents. The experimental values were followed Freundich isothermal model and pseudo-second-order kinetic model, indicating that the adsorption occurred primarily through a multimolecular layer adsorption process, with a strong emphasis on chemisorption. Mechanistic investigations further revealed that the adsorption of Cr(VI) onto C-ZNPs was mediated by various interactions, including electrostatic attraction, complexation, and ion exchange. These findings provide insights into the efficient removal of Cr(VI) by C-ZNPs and suggest potential applications in water treatment and environmental remediation.

15.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723065

RESUMEN

The ocean is a reservoir for CFC-11, a major ozone-depleting chemical. Anthropogenic production of CFC-11 dramatically decreased in the 1990s under the Montreal Protocol, which stipulated a global phase out of production by 2010. However, studies raise questions about current overall emission levels and indicate unexpected increases of CFC-11 emissions of about 10 Gg ⋅ yr-1 after 2013 (based upon measured atmospheric concentrations and an assumed atmospheric lifetime). These findings heighten the need to understand processes that could affect the CFC-11 lifetime, including ocean fluxes. We evaluate how ocean uptake and release through 2300 affects CFC-11 lifetimes, emission estimates, and the long-term return of CFC-11 from the ocean reservoir. We show that ocean uptake yields a shorter total lifetime and larger inferred emission of atmospheric CFC-11 from 1930 to 2075 compared to estimates using only atmospheric processes. Ocean flux changes over time result in small but not completely negligible effects on the calculated unexpected emissions change (decreasing it by 0.4 ± 0.3 Gg ⋅ yr-1). Moreover, it is expected that the ocean will eventually become a source of CFC-11, increasing its total lifetime thereafter. Ocean outgassing should produce detectable increases in global atmospheric CFC-11 abundances by the mid-2100s, with emission of around 0.5 Gg ⋅ yr-1; this should not be confused with illicit production at that time. An illustrative model projection suggests that climate change is expected to make the ocean a weaker reservoir for CFC-11, advancing the detectable change in the global atmospheric mixing ratio by about 5 yr.


Asunto(s)
Atmósfera , Clorofluorocarburos/efectos adversos , Contaminantes Ambientales/efectos adversos , Océanos y Mares , Ozono , Cambio Climático , Monitoreo del Ambiente , Modelos Teóricos
16.
Angew Chem Int Ed Engl ; : e202415940, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39314126

RESUMEN

Single-molecule diode was the first proposed device in molecular electronics. Despite the great efforts and advances over 50 years, the reported rectification ratios, the most critical parameter of a diode, remain moderate for the single-molecule diode. Herein, we report an approach to achieve a larger rectification ratio by adopting the combined strategies of p-type boron doping, the single-layer graphene nodes, and the van der Waals layer-by-layer architecture. Measured current-voltage curves showed one of the as-fabricated single-molecule diodes hit an unprecedented large rectification ratio of 457 at ±1 V. Break junction operations and spectroscopic measurements revealed the three-atom-thick configuration of the single-molecule diodes. With the experimental and theoretical calculation results, we demonstrated the doped boron atoms induced holes to redistribute the electron density, making the asymmetric coupling at positive and negative biases, and the van der Waals interaction promoted asymmetric coupling and significantly boosted diode performance.

17.
Angew Chem Int Ed Engl ; : e202414420, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271463

RESUMEN

Collapsing and degradation of active materials caused by the electrode/electrolyte interface instability in aqueous batteries are one of the main obstacles that mitigate the capacity. Herein by reversing the notorious side reactions include the loss and dissolution of electrode materials, as we applied Ostwald ripening (OR) in the electrochemical cycling of a copper hexacyanoferrate electrode in a hydronium-ion batteries, the dissolved Cu and Fe ions undergo a crystallization process that creates a stable interface layer of cross-linked cubes on the electrode surface. The layer exposed the low-index crystal planes (100) and (110) through OR-induced electrode particle growth, supplemented by vacancy-ordered (100) superlattices that facilitated ion migration. Our design stabilized the electrode-electrolyte interface considerably, achieving a cycle life of one million cycles with capacity retention of 91.6 %, and a capacity retention of 91.7 % after 3000 cycles for a full battery.

18.
Angew Chem Int Ed Engl ; 63(26): e202405592, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38647330

RESUMEN

In aqueous aluminum-ion batteries (AAIBs), the insertion/extraction chemistry of Al3+ often leads to poor kinetics, whereas the rapid diffusion kinetics of hydronium ions (H3O+) may offer the solution. However, the presence of considerable Al3+ in the electrolyte hinders the insertion reaction of H3O+. Herein, we report how oxygen-deficient α-MoO3 nanosheets unlock selective H3O+ insertion in a mild aluminum-ion electrolyte. The abundant oxygen defects impede the insertion of Al3+ due to excessively strong adsorption, while allowing H3O+ to be inserted/diffused through the Grotthuss proton conduction mechanism. This research advances our understanding of the mechanism behind selective H3O+ insertion in mild electrolytes.

19.
Clin Immunol ; 247: 109247, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36724835

RESUMEN

PURPOSE: To describe the effectiveness and tolerability of low-dose interleukin (IL)-2 in treating patients with chronic spontaneous urticaria (CSU) refractory to H1-antihistamines. METHODS: This retrospective study included CSU patients who received treatment with at least one cycle of IL-2, injected intramuscularly at a dose of 1.0 million international units daily for 7 consecutive days, after failing treatment with H1-antihistamines. Patients were followed up for ≥12 weeks. RESULTS: Of the 15 patients, 7 (46.7%) and 11 (73.3%) achieved complete response at Week 2 and Week 12, respectively. The mean change of urticaria control test (UCT) and weekly urticaria activity score (UAS7) from baseline was 6.6 (95% CI, 4.2 to 8.9) and - 16.9 (95% CI, -24.0 to -9.8), respectively, at Week 12. Local injection-site reactions were the most common adverse events. No serious adverse events were reported. CONCLUSION: Low-dose IL-2 treatment improves symptoms and disease control for CSU patients refractory to H1-antihistamines.


Asunto(s)
Urticaria Crónica , Urticaria , Humanos , Interleucina-2/efectos adversos , Estudios Retrospectivos , Enfermedad Crónica , Resultado del Tratamiento , Urticaria Crónica/tratamiento farmacológico , Urticaria/tratamiento farmacológico , Urticaria/diagnóstico , Antagonistas de los Receptores Histamínicos/uso terapéutico
20.
BMC Plant Biol ; 23(1): 99, 2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36800929

RESUMEN

BACKGROUND: The gibberellic acid-stimulated Arabidopsis (GASA) gene encodes a class of cysteine-rich functional proteins and is ubiquitous in plants. Most GASA proteins are influence the signal transmission of plant hormones and regulate plant growth and development, however, their function in Jatropha curcas is still unknown. RESULTS: In this study, we cloned JcGASA6, a member of the GASA family, from J. curcas. The JcGASA6 protein has a GASA-conserved domain and is located in the tonoplast. The three-dimensional structure of the JcGASA6 protein is highly consistent with the antibacterial protein Snakin-1. Additionally, the results of the yeast one-hybrid (Y1H) assay showed that JcGASA6 was activated by JcERF1, JcPYL9, and JcFLX. The results of the Y2H assay showed that both JcCNR8 and JcSIZ1 could interact with JcGASA6 in the nucleus. The expression of JcGASA6 increased continuously during male flower development, and the overexpression of JcGASA6 was associated with filament elongation of the stamens in tobacco. CONCLUSION: JcGASA6, a member of the GASA family in J. curcas, play an important role in growth regulation and floral development (especially in male flower). It is also involved in the signal transduction of hormones, such as ABA, ET, GA, BR, and SA. Also, JcGASA6 is a potential antimicrobial protein determined by its three-dimensional structure.


Asunto(s)
Jatropha , Proteínas de Plantas , Regulación de la Expresión Génica de las Plantas , Giberelinas/metabolismo , Jatropha/genética , Jatropha/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/metabolismo
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