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1.
Nature ; 629(8012): 679-687, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693266

RESUMEN

Pancreatic intraepithelial neoplasias (PanINs) are the most common precursors of pancreatic cancer, but their small size and inaccessibility in humans make them challenging to study1. Critically, the number, dimensions and connectivity of human PanINs remain largely unknown, precluding important insights into early cancer development. Here, we provide a microanatomical survey of human PanINs by analysing 46 large samples of grossly normal human pancreas with a machine-learning pipeline for quantitative 3D histological reconstruction at single-cell resolution. To elucidate genetic relationships between and within PanINs, we developed a workflow in which 3D modelling guides multi-region microdissection and targeted and whole-exome sequencing. From these samples, we calculated a mean burden of 13 PanINs per cm3 and extrapolated that the normal intact adult pancreas harbours hundreds of PanINs, almost all with oncogenic KRAS hotspot mutations. We found that most PanINs originate as independent clones with distinct somatic mutation profiles. Some spatially continuous PanINs were found to contain multiple KRAS mutations; computational and in situ analyses demonstrated that different KRAS mutations localize to distinct cell subpopulations within these neoplasms, indicating their polyclonal origins. The extensive multifocality and genetic heterogeneity of PanINs raises important questions about mechanisms that drive precancer initiation and confer differential progression risk in the human pancreas. This detailed 3D genomic mapping of molecular alterations in human PanINs provides an empirical foundation for early detection and rational interception of pancreatic cancer.


Asunto(s)
Heterogeneidad Genética , Genómica , Imagenología Tridimensional , Neoplasias Pancreáticas , Lesiones Precancerosas , Análisis de la Célula Individual , Adulto , Femenino , Humanos , Masculino , Células Clonales/metabolismo , Células Clonales/patología , Secuenciación del Exoma , Aprendizaje Automático , Mutación , Páncreas/anatomía & histología , Páncreas/citología , Páncreas/metabolismo , Páncreas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Flujo de Trabajo , Progresión de la Enfermedad , Detección Precoz del Cáncer , Oncogenes/genética
2.
Blood ; 143(18): 1825-1836, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38211332

RESUMEN

ABSTRACT: Venetoclax, the first-generation inhibitor of the apoptosis regulator B-cell lymphoma 2 (BCL2), disrupts the interaction between BCL2 and proapoptotic proteins, promoting the apoptosis in malignant cells. Venetoclax is the mainstay of therapy for relapsed chronic lymphocytic leukemia and is under investigation in multiple clinical trials for the treatment of various cancers. Although venetoclax treatment can result in high rates of durable remission, relapse has been widely observed, indicating the emergence of drug resistance. The G101V mutation in BCL2 is frequently observed in patients who relapsed treated with venetoclax and sufficient to confer resistance to venetoclax by interfering with compound binding. Therefore, the development of next-generation BCL2 inhibitors to overcome drug resistance is urgently needed. In this study, we discovered that sonrotoclax, a potent and selective BCL2 inhibitor, demonstrates stronger cytotoxic activity in various hematologic cancer cells and more profound tumor growth inhibition in multiple hematologic tumor models than venetoclax. Notably, sonrotoclax effectively inhibits venetoclax-resistant BCL2 variants, such as G101V. The crystal structures of wild-type BCL2/BCL2 G101V in complex with sonrotoclax revealed that sonrotoclax adopts a novel binding mode within the P2 pocket of BCL2 and could explain why sonrotoclax maintains stronger potency than venetoclax against the G101V mutant. In summary, sonrotoclax emerges as a potential second-generation BCL2 inhibitor for the treatment of hematologic malignancies with the potential to overcome BCL2 mutation-induced venetoclax resistance. Sonrotoclax is currently under investigation in multiple clinical trials.


Asunto(s)
Antineoplásicos , Compuestos Bicíclicos Heterocíclicos con Puentes , Resistencia a Antineoplásicos , Neoplasias Hematológicas , Proteínas Proto-Oncogénicas c-bcl-2 , Sulfonamidas , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Sulfonamidas/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Animales , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral , Mutación , Apoptosis/efectos de los fármacos
3.
Nano Lett ; 24(26): 8179-8188, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38885447

RESUMEN

The unique "Iron Addiction" feature of cancer stem cells (CSCs) with tumorigenicity and plasticity generally contributes to the tumor recurrence and metastasis after a lumpectomy. Herein, a novel "Ferroptosis Amplification" strategy is developed based on integrating gallic acid-modified FeOOH (GFP) and gallocyanine into Pluronic F-127 (F127) and carboxylated chitosan (CC)-based hydrogel for CSCs eradication. This "Ferroptosis Amplifier" hydrogel is thermally sensitive and achieves rapid gelation at the postsurgical wound in a breast tumor model. Specifically, gallocyanine, as the Dickkopf-1 (DKK1) inhibitor, can decrease the expression of SLC7A11 and GPX4 and synergistically induce ferroptosis of CSCs with GFP. Encouragingly, it is found that this combination suppresses the migratory and invasive capability of cancer cells via the downregulation of matrix metalloproteinase 7 (MMP7). The in vivo results further confirm that this "Ferroptosis Amplification" strategy is efficient in preventing tumor relapse and lung metastasis, manifesting an effective and promising postsurgical treatment for breast cancer.


Asunto(s)
Neoplasias de la Mama , Ferroptosis , Hidrogeles , Células Madre Neoplásicas , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Hidrogeles/química , Humanos , Animales , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Femenino , Ratones , Ferroptosis/efectos de los fármacos , Línea Celular Tumoral , Poloxámero/química , Poloxámero/farmacología , Quitosano/química , Quitosano/farmacología , Quitosano/análogos & derivados , Ácido Gálico/farmacología , Ácido Gálico/química , Ácido Gálico/uso terapéutico
4.
Small ; : e2404580, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39149915

RESUMEN

Triple-negative breast cancer (TNBC) responds poorly to immunotherapy due to insufficient immunogenicity and highly immunosuppressive tumor microenvironment (TME). Herein, an intelligent calcium/cobalt-based nanomodulator (Ca,Co)CO3-LND-TCPP@F127-TA (abbreviated as CCLT@FT) is developed to act as a sonodynamic-ferroptosis inducer and metabolic immunoadjuvant to enhance anti-tumor immunotherapy. More details, simultaneous reactive oxygen species (ROS) generation and glutathione (GSH) depletion can be achieved due to the existence of Co2+/Co3+ redox couple in CCLT@FT. Meanwhile, mitochondrial Ca2+ overload and tetrakis(4-carboxyphenyl) porphyrin (TCPP)-mediated sonodynamic therapy (SDT) further amplify the oxidative stress and promote ferroptosis in tumor cells. More impressively, CCLT@FT can modulate lactate metabolism by doping with cobalt and loading with lonidamine (LND, an inhibitor of MCT4), thereby reversing the high-lactate immunosuppressive TME. Furthermore, the combination with immune checkpoint blockade (ICB) therapy is found to achieve superior anti-tumor immunity, which in turn promotes ferroptosis of tumor cells by downregulating SLC7A11 protein, ultimately creating a "cycle" therapy. Overall, this work demonstrates a novel strategy for enhancing anti-tumor immunotherapy based on a closed-loop enhancement therapeutic route between CCLT@FT inducing ferroptosis/lactate metabolism modulation and ICB therapy, providing an alternative and important reference for effective immunotherapy of TNBC.

5.
BMC Nurs ; 23(1): 762, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39415229

RESUMEN

BACKGROUND: Compassion fatigue is common among nurses and can lead to decreased motivation, impaired physical and mental health, and turnover. Nursing interns often face environments the same as professional nurses, yet their compassion fatigue has received less attention. Therefore, this study aims to assess the prevalence and related factors of compassion fatigue among nursing interns. METHODS: This was a cross-sectional study involving 221 nursing interns in 2 tertiary-level hospitals in Shanghai, China. A general information questionnaire was formulated to investigate the demographic characteristics and internship-related factors of nursing interns. Compassion fatigue was assessed using the Professional Quality of Life Scale [compassion satisfaction (CS), burnout (BO), and secondary traumatic stress (STS)]. Psychological resilience, empathy, and perceived stress were evaluated by the Connor-Davidson Resilience Scale, Jefferson Scales of Empathy, and Perceived Stress Scale, respectively. Personality traits were assessed using the extroversion/introversion subscale of the Eysenck Personality Inventory. Descriptive statistics, t-test, one-way analysis of variance (ANOVA), Pearson's correlation analysis, and multiple linear regressions were used to determine the predictors of the main research variables. RESULTS: The prevalence of mild, moderate, and severe compassion fatigue in 221 nursing interns (mean age 21 years, 202 [91.4%] females) was 10.4%, 46.6%, and 43.0%, respectively, and their mean scores for CS, BO, and STS were 29.75 ± 6.39, 28.72 ± 4.78, and 28.51 ± 7.51, respectively. Psychological resilience and empathy were the strongest protective factors for CS and BO, respectively (p < 0.001), and the number of night shifts monthly was the most significant positive independent predictor of STS (p = 0.001). Additionally, male gender negatively predicted CS (p = 0.009). Younger age and extended daily working hours were associated with elevated levels of both BO and STS (p < 0.05). Clinical nursing teachers with intermediate or senior titles, as well as departments of pediatrics and obstetrics had a positive effect on STS (p < 0.05), while internship time had a negative effect on STS (p = 0.005). Furthermore, the variables of perceived stress, personality traits, and choice of nursing profession did not exhibit statistical significance in the multivariate analysis. Related factors predicted 14.2%, 26.2%, and 23.9% of the variance in the model of CS, BO and STS, respectively (all P < 0.001). CONCLUSION: The compassion fatigue of nursing interns was more serious, especially for nursing interns who were male and younger, and who had shorter internship time, departments of pediatrics and obstetrics, and clinical nursing teachers with intermediate or senior titles. Nursing educators can improve the psychological resilience and empathy of nursing interns by offering relevant psychological courses according to the different stages of internship, as well as rationalizing their daily working hours and the frequency of night shifts to improve the compassion fatigue of nursing interns. REGISTRATION NUMBER: ChiCTR2400081968.

6.
Angew Chem Int Ed Engl ; : e202417778, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39420081

RESUMEN

Due to the seamless interfaces between solid polymer electrolytes (SPEs) and electrode materials, SPEs-based all-solid-state sodium-ion batteries (ASSSIBs) are considered promising energy storage systems. However, the sluggish Na+ transport and uncontrollable Na dendrite propagation still hinder the practical application of SPEs-based ASSSIBs. Herein, Ca-doped CeO2 (Ca-CeO2) nanotube framework is synthesized and integrated with poly (ethylene oxide) methyl ether acrylate-perfluoropolyether copolymer (PEOA-PFPE), resulting in multifunctional solid nanocomposite electrolytes (namely SNEs, i.e., PEOA-PFPE/Ca-CeO2). Our investigations demonstrate that the fluorous effect incurred by the fluorine-containing PEOA-PFPE and the oxygen vacancy effect induced by the Ca-CeO2 framework could synergistically promote the dissociation of sodium salt, ultimately enhancing the Na+ mobility in SNEs. Besides, the resultant SNEs construct rapid Na+ transport channels and homogenize the Na deposition in SNEs/Na interface, which effectively prevents the Na dendrite growth. Furthermore, the assembled carbon-coated sodium vanadium phosphate (NVP@C)||PEOA-PFPE/Ca-CeO2||Na coin cell delivers impressive rate capability of 97.9 mA h g-1 at 2 C and outstanding cycling stability with capacity retention of 84.3% after 300 cycles at 1 C. This work illustrates that constructing multifunctional SNEs via incorporating functional inorganic frameworks into fluorine-containing SPEs could be a promising strategy for the commercialization of robust and high-performance ASSSIBs.

7.
J Biol Chem ; 298(11): 102555, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36183831

RESUMEN

Inhibitors targeting Bruton's tyrosine kinase (BTK) have revolutionized the treatment for various B-cell malignancies but are limited by acquired resistance after prolonged treatment as a result of mutations in BTK. Here, by a combination of structural modeling, in vitro assays, and deep phospho-tyrosine proteomics, we demonstrated that four clinically observed BTK mutations-C481F, C481Y, C481R, and L528W-inactivated BTK kinase activity both in vitro and in diffused large B-cell lymphoma (DLBCL) cells. Paradoxically, we found that DLBCL cells harboring kinase-inactive BTK exhibited intact B cell receptor (BCR) signaling, unperturbed transcription, and optimal cellular growth. Moreover, we determined that DLBCL cells with kinase-inactive BTK remained addicted to BCR signaling and were thus sensitive to targeted BTK degradation by the proteolysis-targeting chimera. By performing parallel genome-wide CRISPR-Cas9 screening in DLBCL cells with WT or kinase-inactive BTK, we discovered that DLBCL cells with kinase-inactive BTK displayed increased dependence on Toll-like receptor 9 (TLR9) for their growth and/or survival. Our study demonstrates that the kinase activity of BTK is not essential for oncogenic BCR signaling and suggests that BTK's noncatalytic function is sufficient to sustain the survival of DLBCL.


Asunto(s)
Linfoma de Células B Grandes Difuso , Humanos , Agammaglobulinemia Tirosina Quinasa/genética , Agammaglobulinemia Tirosina Quinasa/metabolismo , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/metabolismo , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/metabolismo , Linfocitos B/metabolismo , Transducción de Señal , Inhibidores de Proteínas Quinasas/farmacología
8.
Mol Pain ; 19: 17448069231190815, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37464536

RESUMEN

Neuropathic pain (NP) occurs frequently in the general population and has a negative impact on the quality of life. There is no effective therapy available yet owing to the complex pathophysiology of NP. In our previous study, we found that urolithin A (UA), a naturally occurring microflora-derived metabolite, could relieve NP in mice by inhibiting the activation of microglia and release of inflammation factors. Here in this study, we sought to investigate whether mitophagy would be activated when UA alleviated NP in mice. We showed that the autophagy flow was blocked in the spinal dorsal horn of the chronic constriction injury (CCI) mice when the most obvious pain behavior occurs. Intraperitoneal injection of UA markedly activated the mitophagy mediated by PTEN-induced kinase 1/Parkin, promoted mitobiogenesis in both neurons and microglia, and alleviated NP in the CCI mice. In summary, our data suggest that UA alleviates NP in mice and meanwhile induces mitophagy activation, which highlights a therapeutic potential of UA in the treatment of NP.


Asunto(s)
Mitofagia , Neuralgia , Humanos , Ratones , Animales , Mitofagia/fisiología , Calidad de Vida , Asta Dorsal de la Médula Espinal/metabolismo , Neuralgia/metabolismo
9.
Phys Chem Chem Phys ; 25(3): 2274-2281, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36597784

RESUMEN

Strong structural asymmetry is actively explored in two-dimensional (2D) materials, because it can give rise to many interesting physical properties. Motivated by the recent synthesis of monolayer Si2Te2, we explored a family of 2D materials, named Janus Si dichalcogenides (JSD), which parallel the Janus transition metal dichalcogenides and exhibit even stronger inversion asymmetry. Using first-principles calculations, we show that their strong structural asymmetry leads to a pronounced intrinsic polar field, sizable spin splitting, and large piezoelectric response. The spin splitting involves an out-of-plane spin component, which is beyond the linear Rashba model. The piezoelectric tensor has a large value in both in-plane d11 coefficient and out-of-plane d31 coefficient, making monolayer JSDs distinct among existing 2D piezoelectric materials. In addition, we find interesting strain-induced phase transitions in these materials. Particularly, there are multiple valleys that compete for the conduction band minimum, which will lead to notable changes in the optical and transport properties under strain. Our work reveals a new family of Si based 2D materials, which could find promising applications in spintronic and piezoelectric devices.

10.
J Nanobiotechnology ; 21(1): 265, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37563614

RESUMEN

BACKGROUND: Emerging ferroptosis-driven therapies based on nanotechnology function either by increasing intracellular iron level or suppressing glutathione peroxidase 4 (GPX4) activity. Nevertheless, the therapeutic strategy of simultaneous iron delivery and GPX4 inhibition remains challenging and has significant scope for improvement. Moreover, current nanomedicine studies mainly use disulfide-thiol exchange to deplete glutathione (GSH) for GPX4 inactivation, which is unsatisfactory because of the compensatory effect of continuous GSH synthesis. METHODS: In this study, we design a two-in-one ferroptosis-inducing nanoplatform using iron-based metal-organic framework (MOF) that combines iron supply and GPX4 deactivation by loading the small molecule buthionine sulfoxide amine (BSO) to block de novo GSH biosynthesis, which can achieve sustainable GSH elimination and dual ferroptosis amplification. A coated lipid bilayer (L) can increase the stability of the nanoparticles and a modified tumor-homing peptide comprising arginine-glycine-aspartic acid (RGD/R) can achieve tumor-specific therapies. Moreover, as a decrease in GSH can alleviate resistance of cancer cells to chemotherapy drugs, oxaliplatin (OXA) was also loaded to obtain BSO&OXA@MOF-LR for enhanced cancer chemo-ferrotherapy in vivo. RESULTS: BSO&OXA@MOF-LR shows a robust tumor suppression effect and significantly improved the survival rate in 4T1 tumor xenograft mice, indicating a combined effect of dual amplified ferroptosis and GSH elimination sensitized apoptosis. CONCLUSION: BSO&OXA@MOF-LR is proven to be an efficient ferroptosis/apoptosis hybrid anti-cancer agent. This study is of great significance for the clinical development of novel drugs based on ferroptosis and apoptosis for enhanced cancer chemo-ferrotherapy.


Asunto(s)
Estructuras Metalorgánicas , Neoplasias , Humanos , Ratones , Animales , Butionina Sulfoximina/farmacología , Oxaliplatino/farmacología , Glutatión
11.
Pestic Biochem Physiol ; 197: 105680, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072537

RESUMEN

We applied a new RNA interference (RNAi) system using rolling circle transcription (RCT) technology to generate RNA microspheres (RMS) for targeting two key chitin synthetic pathway genes [chitin synthase A (CHSA), chitin synthase B (CHSB)] in the larvae of the oriental armyworm (Mythimna separate), a RNAi-unsusceptible agriculturally important lepidopteran pest. Feeding the third-instar larvae with the RMS-CHSA- or RMS-CHSB-treated corn leaf discs suppressed the expression of CHSA by 81.7% or CHSB by 88.1%, respectively, at 72 h. The silencing of CHSA consequently affected the larval development, including the reduced body weight (54.0%) and length (41.3%), as evaluated on the 7th day, and caused significant larval mortalities (51.1%) as evaluated on the 14th day. Similar results were obtained with the larvae fed RMS-CHSB. We also compared RNAi efficiencies among different strategies: 1) two multi-target RMS [i.e., RMS-(CHSA + CHSB), RMS-CHSA + RMS-CHSB], and 2) multi-target RMS and single-target RMS (i.e., either RMS-CHSA or RMS-CHSB) and found no significant differences in RNAi efficiency. By using Cy3-labeled RMS, we confirmed that RMS can be rapidly internalized into Sf9 cells (<6 h). The rapid cellular uptake of RMS accompanied with significant RNAi efficiency through larval feeding suggests that the RCT-based RNAi system can be readily applied to study the gene functions and further developed as bio-pesticides for insect pest management. Additionally, our new RNAi system takes the advantage of the microRNA (miRNA)-mediated RNAi pathway using miRNA duplexes generated in vivo from the RMS by the target insect. The system can be used for RNAi in a wide range of insect species, including lepidopteran insects which often exhibit extremely low RNAi efficiency using other RNAi approaches.


Asunto(s)
MicroARNs , Mariposas Nocturnas , Animales , Interferencia de ARN , Quitina Sintasa/genética , Quitina Sintasa/metabolismo , Microesferas , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Insectos/genética , Larva/metabolismo , ARN Bicatenario
12.
Pestic Biochem Physiol ; 194: 105485, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37532315

RESUMEN

The widespread use of pyrethroid pesticides has brought serious economic losses in sericulture, but there is still no viable solution. The key to solving the problem is to improve silkworm resistance to pesticides, which depends on understanding the resistance mechanism of silkworms to pesticides. This study aimed to use transcriptomes to understand the underlying mechanism of silkworm resistance to fenpropathrin, which will provide a theoretical molecular reference for breeding pesticide-resistant silkworm varieties. In this study, the fat bodies of two strains with differential resistance after 12 h of fenpropathrin feeding were analyzed using RNA-Seq. After feeding fenpropathrin, 760 differentially expressed genes (DEGs) were obtained in the p50(r) strain and 671 DEGs in the 8y strain. The DEGs involved in resistance to fenpropathrin were further identified by comparing the two strains, including 207 upregulated DEGs in p50(r) and 175 downregulated DEGs in 8y. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that these fenpropathrin-related DEGs are mainly enriched in the metabolism and transporter pathways. Moreover, 28 DEGs involved in the metabolic pathway and 18 in the transporter pathway were identified. Furthermore, organic cation transporter protein 6 (BmOCT6), a transporter pathway member, was crucial in enhancing the tolerance of BmN cells to fenpropathrin. Finally, the knockdown of the expression of the homologs of BmOCT6 in Glyphodes pyloalis (G. pyloalis) significantly decreased the resistant level of larvae to fenpropathrin. The findings showed that the metabolism and transporter pathways are associated with resistance to fenpropathrin in silkworm, and OCT6 is an effective and potential target not only for silkworm breeding but also for pest biocontrol.


Asunto(s)
Bombyx , Lepidópteros , Plaguicidas , Piretrinas , Animales , Bombyx/genética , Bombyx/metabolismo , Transcriptoma , Lepidópteros/genética , Cuerpo Adiposo , Perfilación de la Expresión Génica , Piretrinas/toxicidad , Piretrinas/metabolismo , Plaguicidas/metabolismo
13.
Angew Chem Int Ed Engl ; 62(39): e202307208, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37407437

RESUMEN

The irreversibility of anion intercalation-deintercalation is a fundamental issue in determining the cycling stability of a dual-ion battery (DIB). In this work, we demonstrate that using a partially fluorinated carbonate solvent can drive a beneficial fluorinated secondary interphase layer formation. Such layer facilitates reversible anion (de-)intercalation processes by impeding solvent molecule co-intercalation and the associated graphite exfoliation. The enhanced reversibility of anion transport contributes to the overall cycling stability for a Zn-graphite DIB-a high Coulombic efficiency of 98.5 % after 800 cycles, with an attractive discharge capacity of 156 mAh g-1 and a mid-point discharge voltage of ≈1.7 V (at 0.1 A g-1 ). In addition, the formed fluorinated secondary interphase suppresses the self-discharge behavior, preserving 29 times of the capacity retention rate compared to the battery with a commonly used carbonate solvent, after standing for 24 hours. This work provides a simple and effective strategy for addressing the critical challenges in graphite-based DIBs and contributes to fundamental understanding to help accelerate their practical application.

14.
Thorax ; 77(4): 391-397, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34301742

RESUMEN

BACKGROUND: Ambient fine particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) has been associated with deteriorated respiratory health, but evidence on particles in smaller sizes and childhood respiratory health has been limited. METHODS: We collected time-series data on daily respiratory emergency room visits (ERVs) among children under 14 years old in Beijing, China, during 2015-2017. Concurrently, size-fractioned number concentrations of particles in size ranges of 5-560 nm (PNC5-560) and mass concentrations of PM2.5, black carbon (BC) and nitrogen dioxide (NO2) were measured from a fixed-location monitoring station in the urban area of Beijing. Confounder-adjusted Poisson regression models were used to estimate excessive risks (ERs) of particle size fractions on childhood respiratory ERVs, and positive matrix factorisation models were applied to apportion the sources of PNC5-560. RESULTS: Among the 136 925 cases of all-respiratory ERVs, increased risks were associated with IQR increases in PNC25-100 (ER=5.4%, 95% CI 2.4% to 8.6%), PNC100-560 (4.9%, 95% CI 2.5% to 7.3%) and PM2.5 (1.3%, 95% CI 0.1% to 2.5%) at current and 1 prior days (lag0-1). Major sources of PNC5-560 were identified, including nucleation (36.5%), gasoline vehicle emissions (27.9%), diesel vehicle emissions (18.9%) and secondary aerosols (10.6%). Emissions from gasoline and diesel vehicles were found of significant associations with all-respiratory ERVs, with increased ERs of 6.0% (95% CI 2.5% to 9.7%) and 4.4% (95% CI 1.7% to 7.1%) at lag0-1 days, respectively. Exposures to other traffic-related pollutants (BC and NO2) were also associated with increased respiratory ERVs. CONCLUSION: Our findings suggest that exposures to higher levels of PNC5-560 from traffic emissions could be attributed to increased childhood respiratory morbidity, which supports traffic emission control priority in urban areas.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Adolescente , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Niño , Servicio de Urgencia en Hospital , Monitoreo del Ambiente , Humanos , Material Particulado/efectos adversos , Material Particulado/análisis , Emisiones de Vehículos/análisis , Emisiones de Vehículos/toxicidad
15.
Headache ; 62(10): 1383-1394, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36416492

RESUMEN

OBJECTIVE: Using a patient-informed regimen, we conducted an exploratory randomized, double-blind, placebo-controlled study to systematically investigate the effects of psilocybin in cluster headache. BACKGROUND: Sustained reductions in cluster headache burden after limited quantities of psilocybin-containing mushrooms are anecdotally reported, although to date there are no controlled studies investigating these effects. METHODS: Participants were randomized to receive psilocybin (0.143 mg/kg) or placebo (microcrystalline cellulose) in a pulse of three doses, each ~5 days apart. Participants maintained headache diaries starting 2 weeks before and continuing through 8 weeks after the first drug session. A total of 16 participants were randomized to receive experimental drug and 14 were included in the final analysis. RESULTS: In the 3 weeks after the start of the pulse regimen, the change in cluster attack frequency was 0.03 (95% confidence interval [CI] -2.6 to 2.6) attacks/week with placebo (baseline 8.9 [95% CI 3.8 to 14.0]) and -3.2 (95% CI -8.3 to 1.9) attacks/week with psilocybin (baseline 9.6 [95% CI 5.6 to 13.6]; p = 0.251). Group difference in change from baseline had a moderate effect size (d = 0.69). The effect size was small in episodic participants (d = 0.35) but large in chronic participants (d = 1.25), which remained over the entire 8-week period measured (d = 0.81). Changes in cluster attack frequency were not correlated with the intensity of acute psychotropic effects during psilocybin administration. Psilocybin was well-tolerated without any unexpected or serious adverse events. CONCLUSIONS: Findings from this initial, exploratory study provide valuable information for the development of larger, more definitive studies. Efficacy outcomes were negative, owing in part to the small number of participants. The separation of acute psychotropic effects and lasting therapeutic effects underscores the need for further investigation into the mechanism(s) of action of psilocybin in headache disorders.


Asunto(s)
Cefalalgia Histamínica , Humanos , Cefalalgia Histamínica/tratamiento farmacológico , Psilocibina/farmacología , Psilocibina/uso terapéutico , Resultado del Tratamiento , Método Doble Ciego , Cefalea
16.
Environ Sci Technol ; 56(15): 10868-10878, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35834827

RESUMEN

Evidence of the respiratory effects of ambient organic aerosols (e.g., polycyclic aromatic hydrocarbons, PAHs) among patients with chronic diseases is limited. We aimed to assess whether exposure to ambient particle-bound PAHs could worsen small airway functions in patients with chronic obstructive pulmonary disease (COPD) and elucidate the underlying mechanisms involved. Forty-five COPD patients were recruited with four repeated visits in 2014-2015 in Beijing, China. Parameters of pulmonary function and pulmonary/systemic inflammation and oxidative stress were measured at each visit. Linear mixed-effect models were performed to evaluate the associations between PAHs and measurements. In this study, participants experienced an average PAH level of 61.7 ng/m3. Interquartile range increases in exposure to particulate PAHs at prior up to 7 days were associated with reduced small airway functions, namely, decreases of 17.7-35.5% in forced maximal mid-expiratory flow. Higher levels of particulate PAHs were also associated with heightened lung injury and inflammation and oxidative stress. Stronger overall effects were found for PAHs from traffic emissions and coal burning. Exposure to ambient particulate PAHs was capable of impairing small airway functions in elderly patients with COPD, potentially via inflammation and oxidative stress. These findings highlight the importance of control efforts on organic particulate matter from fossil fuel combustion emissions.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Enfermedad Pulmonar Obstructiva Crónica , Anciano , Contaminantes Atmosféricos/análisis , China , Carbón Mineral , Polvo , Monitoreo del Ambiente , Humanos , Inflamación , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Aerosoles y Gotitas Respiratorias
17.
Indoor Air ; 31(6): 1707-1721, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34374125

RESUMEN

Improving air quality in indoor environments where people live is of importance to protect human health. In this systematic review, we assessed the effectiveness of personal-level use of air filtration units in reducing indoor particulate matters (PM) concentrations under real-world situations following systematic review guidelines. A total of 54 articles were included in the review, in which 20 randomized controlled/crossover trials that reported the changes in indoor fine PM (PM2.5 ) concentrations were quantitatively assessed in meta-analysis. Standardized mean differences (SMDs) were calculated for changes in indoor PM concentrations following air filtration interventions. Moderate-to-large reductions of 11%-82% in indoor PM2.5  concentrations were observed with SMD of -1.19 (95% CI: -1.50, -0.88). The reductions in indoor PM concentrations varied by geographical locations, filtration technology employed, indoor environmental characteristics, and air pollution sources. Most studies were graded with low-to-moderate risk of bias; however, the overall certainty of evidence for indoor PM concentration reductions was graded at very low level. Considering the effectiveness of indoor air filtration under practical uses, socio-economic disparities across study populations, and costs of air filter replacement over time, our results highlight the importance of reducing air pollution exposure at the sources.


Asunto(s)
Filtros de Aire , Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire Interior/análisis , Filtración , Humanos , Material Particulado/análisis
18.
Phys Chem Chem Phys ; 22(48): 28359-28364, 2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33300909

RESUMEN

The septuple-atomic-layer VSi2P4 with the same structure of experimentally synthesized MoSi2N4 is predicted to be a spin-gapless semiconductor (SGS) with the generalized gradient approximation (GGA). In this work, the biaxial strain is applied to tune the electronic properties of VSi2P4, and it spans a wide range of properties upon increasing the strain from a ferromagnetic metal (FMM) to SGS to a ferromagnetic semiconductor (FMS) to SGS to a ferromagnetic half-metal (FMHM). Due to broken inversion symmetry, the coexistence of ferromagnetism and piezoelectricity can be achieved in FMS VSi2P4 with the strain range of 0% to 4%. The calculated piezoelectric strain coefficients d11 for 1%, 2% and 3% strains are 4.61 pm V-1, 4.94 pm V-1 and 5.27 pm V-1, respectively, which are greater than or close to a typical value of 5 pm V-1 for bulk piezoelectric materials. Finally, similar to VSi2P4, the coexistence of piezoelectricity and ferromagnetism can be realized by strain in the VSi2N4 monolayer. Our works show that VSi2P4 in the FMS phase with intrinsic piezoelectric properties can have potential applications in spin electronic devices.

20.
Microbiology (Reading) ; 163(11): 1637-1640, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29034863

RESUMEN

Genus Comamonas is a group of bacteria that are able to degrade a variety of environmental waste. Comamonas aquatica CJG (C. aquatica) in this genus is able to absorb low-density lipoprotein but not high-density lipoprotein of human serum. Using 1H and 13C NMR spectroscopy, we found that the O-polysaccharide (O-antigen) of this bacterium is comprised of a disaccharide repeat (O-unit) of d-glucose and 2-O-acetyl-l-rhamnose, which is shared by Serratia marcescens O6. The O-antigen gene cluster of C. aquatica, which is located between coaX and tnp4 genes, contains rhamnose synthesis genes, glycosyl and acetyl transferase genes, and ATP-binding cassette transporter genes, and therefore is consistent with the O-antigen structure determined here.


Asunto(s)
Comamonas/genética , Familia de Multigenes/genética , Antígenos O/química , Antígenos O/genética , Proteínas Bacterianas/química , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética con Carbono-13 , Comamonas/química , Comamonas/enzimología , Disacáridos/análisis , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Glucosa , Antígenos O/aislamiento & purificación , Estructura Secundaria de Proteína , Espectroscopía de Protones por Resonancia Magnética , Ramnosa
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