Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 325
Filtrar
1.
Proc Natl Acad Sci U S A ; 121(6): e2305947121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38289952

RESUMEN

Optic neuropathies, characterized by injury of retinal ganglion cell (RGC) axons of the optic nerve, cause incurable blindness worldwide. Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEVs) represent a promising "cell-free" therapy for regenerative medicine; however, the therapeutic effect on neural restoration fluctuates, and the underlying mechanism is poorly understood. Here, we illustrated that intraocular administration of MSC-sEVs promoted both RGC survival and axon regeneration in an optic nerve crush mouse model. Mechanistically, MSC-sEVs primarily targeted retinal mural cells to release high levels of colony-stimulating factor 3 (G-CSF) that recruited a neural restorative population of Ly6Clow monocytes/monocyte-derived macrophages (Mo/MΦ). Intravitreal administration of G-CSF, a clinically proven agent for treating neutropenia, or donor Ly6Clow Mo/MΦ markedly improved neurological outcomes in vivo. Together, our data define a unique mechanism of MSC-sEV-induced G-CSF-to-Ly6Clow Mo/MΦ signaling in repairing optic nerve injury and highlight local delivery of MSC-sEVs, G-CSF, and Ly6Clow Mo/MΦ as therapeutic paradigms for the treatment of optic neuropathies.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Traumatismos del Nervio Óptico , Ratones , Animales , Axones/metabolismo , Factor Estimulante de Colonias de Granulocitos/metabolismo , Regeneración Nerviosa/fisiología , Traumatismos del Nervio Óptico/terapia , Traumatismos del Nervio Óptico/metabolismo , Células Ganglionares de la Retina/fisiología , Células Madre Mesenquimatosas/metabolismo , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo
2.
Mol Psychiatry ; 29(3): 730-741, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38221548

RESUMEN

Remote memory usually decreases over time, whereas remote drug-cue associated memory exhibits enhancement, increasing the risk of relapse during abstinence. Memory system consolidation is a prerequisite for remote memory formation, but neurobiological underpinnings of the role of consolidation in the enhancement of remote drug memory are unclear. Here, we found that remote cocaine-cue associated memory was enhanced in rats that underwent self-administration training, together with a progressive increase in the response of prelimbic cortex (PrL) CaMKII neurons to cues. System consolidation was required for the enhancement of remote cocaine memory through PrL CaMKII neurons during the early period post-training. Furthermore, dendritic spine maturation in the PrL relied on the basolateral amygdala (BLA) input during the early period of consolidation, contributing to remote memory enhancement. These findings indicate that memory consolidation drives the enhancement of remote cocaine memory through a time-dependent increase in activity and maturation of PrL CaMKII neurons receiving a sustained BLA input.


Asunto(s)
Complejo Nuclear Basolateral , Cocaína , Consolidación de la Memoria , Neuronas , Corteza Prefrontal , Animales , Consolidación de la Memoria/efectos de los fármacos , Consolidación de la Memoria/fisiología , Cocaína/farmacología , Masculino , Ratas , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Complejo Nuclear Basolateral/efectos de los fármacos , Complejo Nuclear Basolateral/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Memoria a Largo Plazo/efectos de los fármacos , Memoria a Largo Plazo/fisiología , Señales (Psicología) , Ratas Sprague-Dawley , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Autoadministración , Espinas Dendríticas/efectos de los fármacos , Espinas Dendríticas/metabolismo , Espinas Dendríticas/fisiología , Trastornos Relacionados con Cocaína/metabolismo , Trastornos Relacionados con Cocaína/fisiopatología , Memoria/efectos de los fármacos , Memoria/fisiología
3.
Mol Psychiatry ; 29(3): 838-846, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38233469

RESUMEN

Previous studies have shown that excessive alcohol consumption is associated with poor sleep. However, the health risks of light-to-moderate alcohol consumption in relation to sleep traits (e.g., insomnia, snoring, sleep duration and chronotype) remain undefined, and their causality is still unclear in the general population. To identify the association between alcohol consumption and multiple sleep traits using an observational and Mendelian randomization (MR) design. Observational analyses and one-sample MR (linear and nonlinear) were performed using clinical and individual-level genetic data from the UK Biobank (UKB). Two-sample MR was assessed using summary data from genome-wide association studies from the UKB and other external consortia. Phenotype analyses were externally validated using data from the National Health and Nutrition Examination Survey (2017-2018). Data analysis was conducted from January 2022 to October 2022. The association between alcohol consumption and six self-reported sleep traits (short sleep duration, long sleep duration, chronotype, snoring, waking up in the morning, and insomnia) were analysed. This study included 383,357 UKB participants (mean [SD] age, 57.0 [8.0] years; 46% male) who consumed a mean (SD) of 9.0 (10.0) standard drinks (one standard drink equivalent to 14 g of alcohol) per week. In the observational analyses, alcohol consumption was significantly associated with all sleep traits. Light-moderate-heavy alcohol consumption was linearly linked to snoring and the evening chronotype but nonlinearly associated with insomnia, sleep duration, and napping. In linear MR analyses, a 1-SD (14 g) increase in genetically predicted alcohol consumption was associated with a 1.14-fold (95% CI, 1.07-1.22) higher risk of snoring (P < 0.001), a 1.28-fold (95% CI, 1.20-1.37) higher risk of evening chronotype (P < 0.001) and a 1.24-fold (95% CI, 1.13-1.36) higher risk of difficulty waking up in the morning (P < 0.001). Nonlinear MR analyses did not reveal significant results after Bonferroni adjustment. The results of the two-sample MR analyses were consistent with those of the one-sample MR analyses, but with a slightly attenuated overall estimate. Our findings suggest that even low levels of alcohol consumption may affect sleep health, particularly by increasing the risk of snoring and evening chronotypes. The negative effects of alcohol consumption on sleep should be made clear to the public in order to promote public health.


Asunto(s)
Consumo de Bebidas Alcohólicas , Bancos de Muestras Biológicas , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Trastornos del Inicio y del Mantenimiento del Sueño , Sueño , Humanos , Análisis de la Aleatorización Mendeliana/métodos , Consumo de Bebidas Alcohólicas/genética , Consumo de Bebidas Alcohólicas/epidemiología , Masculino , Reino Unido/epidemiología , Femenino , Persona de Mediana Edad , Sueño/genética , Sueño/fisiología , Anciano , Trastornos del Inicio y del Mantenimiento del Sueño/genética , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Ronquido/genética , Ronquido/epidemiología , Adulto , Fenotipo , Trastornos del Sueño-Vigilia/genética , Trastornos del Sueño-Vigilia/epidemiología , Polimorfismo de Nucleótido Simple/genética , Biobanco del Reino Unido
4.
Gastroenterology ; 165(1): 88-103, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36921674

RESUMEN

BACKGROUND & AIMS: Gastric cancer (GC) is a major cancer type characterized by high heterogeneity in both tumor cells and the tumor immune microenvironment (TIME). One intractable GC subtype is gastric signet-ring cell carcinoma (GSRCC), which is associated with poor prognosis. However, it remains unclear what the GSRCC TIME characteristics are and how these characteristics may contribute to clinical outcomes. METHODS: We enrolled 32 patients with advanced GC of diverse subtypes and profiled their TIME using an immune-targeted single-cell profiling strategy, including (1) immune-targeted single-cell RNA sequencing (n = 20 patients) and (2) protein expression profiling by a targeted antibody panel for mass cytometry (n = 12 patients). We also generated matched V(D)J (variable, diversity, and joining gene segments) sequencing of T and B cells along CD45+ immunocytes. RESULTS: We found that compared to non-GSRCC, the GSRCC TIME appears to be quiescent, where both CD4+ and CD8+ T cells are difficult to be mobilized, which further impairs the proper functions of B cells. CXCL13, mainly produced by follicular helper T cells, T helper type 17, and exhausted CD8+ T cells, is a central coordinator of this transformation. We show that CXCL13 expression can predict the response to immune checkpoint blockade in GC patients, which may be related to its effects on tertiary lymphoid structures. CONCLUSIONS: Our study provides a comprehensive molecular portrait of immune cell compositions and cell states in advanced GC patients, highlighting adaptive immune irresponsiveness in GSRCC and a mediator role of CXCL13 in TIME. Our targeted single-cell transcriptomic and proteomic profiling represents a powerful approach for TIME-oriented translational research.


Asunto(s)
Carcinoma de Células en Anillo de Sello , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Linfocitos T CD8-positivos , Proteómica , Carcinoma de Células en Anillo de Sello/genética , Microambiente Tumoral
5.
Small ; 20(11): e2306485, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37941515

RESUMEN

The transformation of the two-electron oxygen reduction reaction (2e-ORR) to produce hydrogen peroxide (H2 O2 ) is a promising green synthesis approach that can replace the high-energy consumption anthraquinone process. However, designing and fabricating low-cost, non-precious metal electrocatalysts for 2e-ORR remains a challenge. In this study, a method of combining complexation precipitation and thermal treatment to synthesize 2D copper-tin composite nanosheets to serve as the 2e-ORR electrocatalysts is utilized, achieving a high H2 O2 selectivity of 92.8% in 0.1 m KOH, and a bulk H2 O2 electrosynthesis yield of 1436 mmol·gcat -1 ·h-1 using a flow cell device. Remarkably, the H2 O2 selectivity of this catalyst decreases by only 0.5% after 10,000 cyclic voltammetry (CV) cycles. In addition, it demonstrates that the same catalyst can achieve 97% removal of the organic pollutant methyl blue in an aqueous system solution within 1 h using the on-site degradation technology. A reasonable control of defect concentration on the 2D copper-tin composite nanosheets that can effectively improve the electrocatalytic performance is found. Density functional theory calculations confirm that the surface of the 2D copper-tin composite nanosheets is conducive to the adsorption of the key intermediate OOH* , highlighting its excellent electrocatalytic performance for ORR with high H2 O2 selectivity.

6.
Chemistry ; 30(6): e202303025, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37902103

RESUMEN

In recent years, layered double hydroxides (LDH) nanosheets have garnered substantial attention as intriguing inorganic anionic layered clay materials. These nanosheets have captured the attention of researchers due to their unique physicochemical properties. This review aims to showcase the latest advancements in laboratory research concerning LDH nanosheets, with a specific emphasis on their methods of preparation. This review provides detailed insights into the factors influencing the anionic conductivity of LDH, along with delineating the applications of LDH nanosheets in the realm of energy conversion. Notably, the review highlights the crucial role of LDH nanosheets in the oxygen evolution reaction (OER), a vital process in water splitting and diverse electrochemical applications. The review emphasizes the significant potential of LDH nanosheets in enhancing supercapacitor technology, owing to their high surface area and exceptional charge storage capacity. Additionally, it elucidates the prospective application of LDH nanosheets as anion exchange membranes in anion exchange membrane fuel cells, potentially revolutionizing fuel cell performance through improved efficiency and stability facilitated by enhanced ion transport properties.

7.
Mol Psychiatry ; 28(10): 4056-4069, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37491461

RESUMEN

The increasing number of coronavirus disease 2019 (COVID-19) infections have highlighted the long-term consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection called long COVID. Although the concept and definition of long COVID are described differently across countries and institutions, there is general agreement that it affects multiple systems, including the immune, respiratory, cardiovascular, gastrointestinal, neuropsychological, musculoskeletal, and other systems. This review aims to provide a synthesis of published epidemiology, symptoms, and risk factors of long COVID. We also summarize potential pathophysiological mechanisms and biomarkers for precise prevention, early diagnosis, and accurate treatment of long COVID. Furthermore, we suggest evidence-based guidelines for the comprehensive evaluation and management of long COVID, involving treatment, health systems, health finance, public attitudes, and international cooperation, which is proposed to improve the treatment strategies, preventive measures, and public health policy making of long COVID.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Síndrome Post Agudo de COVID-19 , Factores de Riesgo
8.
Mol Psychiatry ; 28(4): 1793-1801, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36690792

RESUMEN

Long-term sequelae clustering phenotypes are important for precise health care management in COVID-19 survivors. We reported findings for 1000 survivors 20 months after diagnosis of COVID-19 in a community-based cohort in China. Sequelae symptoms were collected from a validated questionnaire covering 27 symptoms involved in five organ systems including self-reported physical condition, dyspnea, cognitive function and mental health. The generalized symptoms were reported with the highest rate (60.7%), followed by the mental (48.3%), cardiopulmonary (39.8%), neurological (37.1%; cognitive impairment, 15.6%), and digestive symptoms (19.1%). Four clusters were identified by latent class analysis: 44.9% no or mild group (cluster 1), 29.2% moderate group with mainly physical impairment (cluster 2), 9.6% moderate group with mainly cognitive and mental health impairment (cluster 3), and 16.3% severe group (cluster 4). Physical comorbidities or history of mental disorders, longer hospitalization periods and severe acute illness predicted severe group. For moderate group, adults less than 60 years, with physical comorbidities and severe acute illness were more likely to have physical symptoms, while adult women with longer hospitalization stays had increased risk of cognitive and mental health impairment. Overall, among more than half of community COVID-19 survivors who presented moderate or severe sequelae 20 months after recovery, three-tenth had physical vulnerability that may require physical therapy aiming to improve functioning, one-tenth mental or cognitive vulnerable cases need psychotherapy and cognitive rehabilitation, and one-sixth severe group needs multidisciplinary clinical management. The remaining half is free to clinical intervention. Our findings introduced an important framework to map numerous symptoms to precise classification of the clinical sequelae phenotype and provide information to guide future stratified recovery interventions.


Asunto(s)
COVID-19 , Disfunción Cognitiva , Humanos , Femenino , Estudios de Cohortes , Enfermedad Aguda , Disfunción Cognitiva/epidemiología , Cognición
9.
Mol Psychiatry ; 28(1): 423-433, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35668159

RESUMEN

The long-term physical and mental sequelae of COVID-19 are a growing public health concern, yet there is considerable uncertainty about their prevalence, persistence and predictors. We conducted a comprehensive, up-to-date meta-analysis of survivors' health consequences and sequelae for COVID-19. PubMed, Embase and the Cochrane Library were searched through Sep 30th, 2021. Observational studies that reported the prevalence of sequelae of COVID-19 were included. Two reviewers independently undertook the data extraction and quality assessment. Of the 36,625 records identified, a total of 151 studies were included involving 1,285,407 participants from thirty-two countries. At least one sequelae symptom occurred in 50.1% (95% CI 45.4-54.8) of COVID-19 survivors for up to 12 months after infection. The most common investigation findings included abnormalities on lung CT (56.9%, 95% CI 46.2-67.3) and abnormal pulmonary function tests (45.6%, 95% CI 36.3-55.0), followed by generalized symptoms, such as fatigue (28.7%, 95% CI 21.0-37.0), psychiatric symptoms (19.7%, 95% CI 16.1-23.6) mainly depression (18.3%, 95% CI 13.3-23.8) and PTSD (17.9%, 95% CI 11.6-25.3), and neurological symptoms (18.7%, 95% CI 16.2-21.4), such as cognitive deficits (19.7%, 95% CI 8.8-33.4) and memory impairment (17.5%, 95% CI 8.1-29.6). Subgroup analysis showed that participants with a higher risk of long-term sequelae were older, mostly male, living in a high-income country, with more severe status at acute infection. Individuals with severe infection suffered more from PTSD, sleep disturbance, cognitive deficits, concentration impairment, and gustatory dysfunction. Survivors with mild infection had high burden of anxiety and memory impairment after recovery. Our findings suggest that after recovery from acute COVID-19, half of survivors still have a high burden of either physical or mental sequelae up to at least 12 months. It is important to provide urgent and appropriate prevention and intervention management to preclude persistent or emerging long-term sequelae and to promote the physical and psychiatric wellbeing of COVID-19 survivors.


Asunto(s)
COVID-19 , Femenino , Humanos , Masculino , Ansiedad , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/psicología , Pandemias , Síndrome Post Agudo de COVID-19/patología , Pulmón/patología , Factores de Riesgo
10.
J Sleep Res ; 33(1): e13942, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37254247

RESUMEN

Polysomnographic studies have been performed to investigate the first-night effect in insomnia disorder. However, these studies have revealed discrepant findings. This meta-analysis aimed to summarise and quantify the characteristics of the first-night effect in insomnia disorder. We performed a systematic search of the PubMed, Medline, EMBASE, Web of Science and PsycINFO databases to identify studies published through October 2019. A total of 11,862 articles were identified, and seven studies with eight independent populations were included in the meta-analysis. A total of 639 patients with insomnia disorder and 171 healthy controls underwent more than 2 consecutive nights of in-laboratory polysomnography. Pooled results demonstrated that both variables of sleep continuity and sleep architecture, other than slow-wave sleep were significantly altered in the first-night effect in insomnia disorder. Furthermore, the results indicated that patients with insomnia disorder had a disruption of sleep continuity in the first-night effect, including increased sleep onset latency and reduced total sleep time, compared to healthy controls. Overall, the findings show that patients with insomnia disorder experience the first-night effect, rather than reverse first-night effect, and the profiles of the first-night effect in patients with insomnia are different from healthy controls. These indicate that an adaptation night is necessary when sleep continuity and sleep architecture is to be studied in patients with insomnia disorder. More well-designed studies with large samples are needed to confirm the results.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Sueño de Onda Lenta , Humanos , Sueño , Polisomnografía/métodos , Latencia del Sueño
11.
Environ Sci Technol ; 58(1): 391-399, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38147515

RESUMEN

Low-cost polyamide thin-film composite membranes are being explored as alternatives to expensive cation exchange membranes for seawater electrolysis. However, transport of chloride from seawater to the anode chamber must be reduced to minimize the production of chlorine gas. A double-polyamide composite structure was created that reduced the level of chloride transport. Adding five polyamide layers on the back of a conventional polyamide composite membrane reduced the chloride ion transport by 53% and did not increase the applied voltage. Decreased chloride permeation was attributed to enhanced electrostatic and steric repulsion created by the new polyamide layers. Charge was balanced through increased sodium ion transport (52%) from the anolyte to the catholyte rather than through a change in the transport of protons and hydroxides. As a result, the Nernstian loss arising from the pH difference between the anolyte and catholyte remained relatively constant during electrolysis despite membrane modifications. This lack of a change in pH showed that transport of protons and hydroxides during electrolysis was independent of salt ion transport. Therefore, only sodium ion transport could compensate for the reduction of chloride flux to maintain the set current. Overall, these results prove the feasibility of using a double-polyamide structure to control chloride permeation during seawater electrolysis without sacrificing energy consumption.


Asunto(s)
Cloruros , Nylons , Nylons/química , Protones , Electrólisis , Agua de Mar/química , Hidróxidos , Sodio , Membranas Artificiales
12.
Environ Sci Technol ; 58(2): 1131-1141, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38169368

RESUMEN

Hydrogen gas evolution using an impure or saline water feed is a promising strategy to reduce overall energy consumption and investment costs for on-site, large-scale production using renewable energy sources. The chlorine evolution reaction is one of the biggest concerns in hydrogen evolution with impure water feeds. The "alkaline design criterion" in impure water electrolysis was examined here because water oxidation catalysts can exhibit a larger kinetic overpotential without interfering chlorine chemistry under alkaline conditions. Here, we demonstrated that relatively inexpensive thin-film composite (TFC) membranes, currently used for high-pressure reverse osmosis (RO) desalination applications, can have much higher rejection of Cl- (total crossover of 2.9 ± 0.9 mmol) than an anion-exchange membrane (AEM) (51.8 ± 2.3 mmol) with electrolytes of 0.5 M KOH for the anolyte and 0.5 M NaCl for the catholyte with a constant current (100 mA/cm2 for 20 h). The membrane resistances, which were similar for the TFC membrane and the AEM based on electrochemical impedance spectroscopy (EIS) and Ohm's law methods, could be further reduced by increasing the electrolyte concentration or removal of the structural polyester supporting layer (TFC-no PET). TFC membranes could enable pressurized gas production, as this membrane was demonstrated to be mechanically stable with no change in permeate flux at 35 bar. These results show that TFC membranes provide a novel pathway for producing green hydrogen with a saline water feed at elevated pressures compared to systems using AEMs or porous diaphragms.


Asunto(s)
Cloro , Hidrógeno , Metacrilatos , Ósmosis , Membranas Artificiales , Aguas Salinas , Cloruros
13.
Allergol Int ; 73(1): 115-125, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37567832

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common chronic inflammatory disease of the nasal cavity and paranasal sinuses. The role of neutrophils in the pathogenesis of CRSwNP has attracted more attention in recent years, due to its association with more severe disease and reduced steroid responsiveness. Lipocalin-2 (LCN2) has been found to modulate neutrophils infiltration in other neutrophilic inflammation including inflammatory bowel disease, rheumatoid arthritis, and psoriasis. The aim was to evaluate the expression and regulator role of LCN2 in neutrophilic inflammation in CRSwNP, and its role as a potential biomarker predicting non-eosinophilic CRSwNP (neCRSwNP). METHODS: Bioinformatic analysis, immunostainings, real-time PCR and ELISA were used to analyze the expression and location of LCN2 in nasal tissues. The expression of proinflammatory mediators were assessed in nasal tissues and secretions. LCN2 production in human nasal epithelial cells (HNECs) and neutrophils, as well as its role in neutrophilic inflammation was evaluated by in vitro experiments. RESULTS: LCN2 was mainly located in neutrophils and HNECs of nasal polyps. LCN2 expression was also significantly higher in the polyp tissue and nasal secretions from patients with neCRSwNP. The LCN2 levels were positively correlated with type 3 inflammation markers, including G-CSF, IL-8, and IL-17. LCN2 expression could be upregulated by IL-17 A and TNF-α in HNECs, and LCN2 could also promote the expression of IL-8 in dispersed polyp cells and HNECs. CONCLUSIONS: LCN2 could serve as a novel biomarker predicting patients with neCRSwNP, and the increased expression of LCN2 may participate in the pathogenesis of neCRSwNP.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Humanos , Pólipos Nasales/metabolismo , Interleucina-17/metabolismo , Rinitis/complicaciones , Sinusitis/metabolismo , Lipocalina 2/genética , Interleucina-8/metabolismo , Inflamación , Biomarcadores , Enfermedad Crónica
14.
J Environ Sci (China) ; 145: 128-138, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38844313

RESUMEN

Zeolites are a promising support for Pd catalysts in lean methane (CH4) combustion. Herein, three types of zeolites (H-MOR, H-ZSM-5 and H-Y) were selected to estimate their structural effects and deactivation mechanisms in CH4 combustion. We show that variations in zeolite structure and surface acidity led to distinct changes in Pd states. Pd/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity, with activation energy (Ea) at 73 kJ/mol, while Pd/H-ZSM-5 displayed the highest turnover frequency (TOF) at 19.6 × 10-3 sec-1, presumably owing to its large particles with more step sites providing active sites in one particle for CH4 activation. Pd/H-Y with dispersed PdO within pore channels and/or Pd2+ ions on ion-exchange sites yielded the lowest apparent activity and TOF. Furthermore, Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition, but introducing 3 vol.% H2O caused the CH4 conversion rate on Pd/H-MOR drop from 100% to 63% and that on Pd/H-ZSM-5 decreased remarkably from 82% to 36%. The former was shown to originate from zeolite structural dealumination, and the latter principally owed to Pd aggregation and the loss of active PdO.


Asunto(s)
Metano , Paladio , Zeolitas , Zeolitas/química , Metano/química , Catálisis , Paladio/química , Modelos Químicos
15.
Angew Chem Int Ed Engl ; 63(22): e202402255, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38551062

RESUMEN

With the prosperity of the development of carbon nanorings, certain topologically or functionally unique units-embedded carbon nanorings have sprung up in the past decade. Herein, we report the facile and efficient synthesis of three cyclooctatetraene-embedded carbon nanorings (COTCNRs) that contain three (COTCNR1 and COTCNR2) and four (COTCNR3) COT units in a one-pot Yamamoto coupling. These nanorings feature hoop-shaped segments of Gyroid (G-), Diamond (D-), and Primitive (P-) type carbon schwarzites. The conformations of the trimeric nanorings COTCNR1 and COTCNR2 are shape-persistent, whereas the tetrameric COTCNR3 possesses a flexible carbon skeleton which undergoes conformational changes upon forming host-guest complexes with fullerenes (C60 and C70), whose co-crystals may potentially serve as fullerene-based semiconducting supramolecular wires with electrical conductivities on the order of 10-7 S cm-1 (for C60⊂COTCNR3) and 10-8 S cm-1 (for C70⊂COTCNR3) under ambient conditions. This research not only describes highly efficient one-step syntheses of three cyclooctatetraene-embedded carbon nanorings which feature hoop-shaped segments of distinctive topological carbon schwarzites, but also demonstrates the potential application in electronics of the one-dimensional fullerene arrays secured by COTCNR3.

16.
Hum Brain Mapp ; 44(8): 3112-3122, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36919400

RESUMEN

It remains challenging to identify depression accurately due to its biological heterogeneity. As people suffering from depression are associated with functional brain network alterations, we investigated subtypes of patients with first-episode drug-naive (FEDN) depression based on brain network characteristics. This study included data from 91 FEDN patients and 91 matched healthy individuals obtained from the International Big-Data Center for Depression Research. Twenty large-scale functional connectivity networks were computed using group information guided independent component analysis. A multivariate unsupervised normative modeling method was used to identify subtypes of FEDN and their associated networks, focusing on individual-level variability among the patients for quantifying deviations of their brain networks from the normative range. Two patient subtypes were identified with distinctive abnormal functional network patterns, consisting of 10 informative connectivity networks, including the default mode network and frontoparietal network. 16% of patients belonged to subtype I with larger extreme deviations from the normal range and shorter illness duration, while 84% belonged to subtype II with weaker extreme deviations and longer illness duration. Moreover, the structural changes in subtype II patients were more complex than the subtype I patients. Compared with healthy controls, both increased and decreased gray matter (GM) abnormalities were identified in widely distributed brain regions in subtype II patients. In contrast, most abnormalities were decreased GM in subtype I. The informative functional network connectivity patterns gleaned from the imaging data can facilitate the accurate identification of FEDN-MDD subtypes and their associated neurobiological heterogeneity.


Asunto(s)
Trastorno Depresivo Mayor , Humanos , Trastorno Depresivo Mayor/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Vías Nerviosas/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Corteza Cerebral , Mapeo Encefálico
17.
Chemistry ; 29(53): e202300695, 2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37408381

RESUMEN

The triphenylmethane (trityl) group has been recognized as a supramolecular synthon in crystal engineering, molecular machine rotors and stereochemical chirality inductors in materials science. Herein we demonstrate for the first time how it can be utilized in the domain of molecular magnetic materials through shaping of single molecule magnet (SMM) properties within the lanthanide complexes in tandem with other non-covalent interactions. Trityl-appended mono- (HL1 ) and bis-compartmental (HL2 ) hydrazone ligands were synthesized and complexated with Dy(III) and Er(III) triflate and nitrate salts to generate four monometallic (1-4) and two bimetallic (5, 6) complexes. The static and dynamic magnetic properties of 1-6 were investigated, revealing that only ligand HL1 induces assemblies (1-4) capable of showing SMM behaviour, with Dy(III) congeners (1, 2) able to exhibit the phenomenon also under zero field conditions. Theoretical ab initio studies helped in determination of Dy(III) energetic levels, magnetic anisotropic axes and corroborated magnetic relaxation mechanisms to be a combination of Raman and quantum tunnelling in zero dc field, the latter being cancelled in the optimum non-zero dc field. Our work represents the first study of magneto-structural correlations within the trityl Ln-SMMs, leading to generation of slowly relaxing zero-field dysprosium complexes within the hydrogen-bonded assemblies.

18.
Mol Psychiatry ; 27(1): 19-33, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34580416

RESUMEN

Infectious diseases, including COVID-19, are crucial public health issues and may lead to considerable fear among the general public and stigmatization of, and discrimination against, specific populations. This meta-analysis aimed to estimate the pooled prevalence of stigma in infectious disease epidemics. We systematically searched PubMed, PsycINFO, Embase, MEDLINE, Web of Science, and Cochrane databases since inception to June 08, 2021, and reported the prevalence of stigma towards people with infectious diseases including SARS, H1N1, MERS, Zika, Ebola, and COVID-19. A total of 50 eligible articles were included that contributed 51 estimates of prevalence in 92722 participants. The overall pooled prevalence of stigma across all populations was 34% [95% CI: 28-40%], including enacted stigma (36% [95% CI: 28-44%]) and perceived stigma (31% [95% CI: 22-40%]). The prevalence of stigma in patients, community population, and health care workers, was 38% [95% CI: 12- 65%], 36% [95% CI: 28-45%], and 30% [95% CI: 20-40%], respectively. The prevalence of stigma in participants from low- and middle-income countries was 37% [95% CI: 29-45%], which is higher than that from high-income countries (27% [95% CI: 18-36%]) though this difference was not statistically significant. A similar trend of prevalence of stigma was also observed in individuals with lower education (47% [95% CI: 23-71%]) compared to higher education level (33% [95% CI: 23-4%]). These findings indicate that stigma is a significant public health concern, and effective and comprehensive interventions are needed to counteract the damaging effects of the infodemics during infectious disease epidemics, including COVID-19, and reduce infectious disease-related stigma.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Subtipo H1N1 del Virus de la Influenza A , Infección por el Virus Zika , Virus Zika , Humanos , Prevalencia
19.
Mol Psychiatry ; 27(8): 3214-3222, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35668158

RESUMEN

Infectious disease epidemics have become more frequent and more complex during the 21st century, posing a health threat to the general public and leading to psychological symptoms. The current study was designed to investigate the prevalence of and risk factors associated with depression, anxiety and insomnia symptoms during epidemic outbreaks, including COVID-19. We systematically searched the PubMed, Embase, Web of Science, OVID, Medline, Cochrane databases, bioRxiv and medRxiv to identify studies that reported the prevalence of depression, anxiety or insomnia during infectious disease epidemics, up to August 14th, 2020. Prevalence of mental symptoms among different populations including the general public, health workers, university students, older adults, infected patients, survivors of infection, and pregnant women across all types of epidemics was pooled. In addition, prevalence of mental symptoms during COVID-19 was estimated by time using meta-regression analysis. A total of 17,506 papers were initially retrieved, and a final of 283 studies met the inclusion criteria, representing a total of 948,882 individuals. The pooled prevalence of depression ranged from 23.1%, 95% confidential intervals (95% CI: [13.9-32.2]) in survivors to 43.3% (95% CI: [27.1-59.6]) in university students, the pooled prevalence of anxiety ranged from 25.0% (95% CI: [12.0-38.0]) in older adults to 43.3% (95% CI: [23.3-63.3]) in pregnant women, and insomnia symptoms ranged from 29.7% (95% CI: [24.4-34.9]) in the general public to 58.4% (95% CI: [28.1-88.6]) in university students. Prevalence of moderate-to-severe mental symptoms was lower but had substantial variation across different populations. The prevalence of mental problems increased over time during the COVID-19 pandemic among the general public, health workers and university students, and decreased among infected patients. Factors associated with increased prevalence for all three mental health symptoms included female sex, and having physical disorders, psychiatric disorders, COVID infection, colleagues or family members infected, experience of frontline work, close contact with infected patients, high exposure risk, quarantine experience and high concern about epidemics. Frequent exercise and good social support were associated with lower risk for these three mental symptoms. In conclusion, mental symptoms are common during epidemics with substantial variation across populations. The population-specific psychological crisis management are needed to decrease the burden of psychological problem and improve the mental wellbeing during epidemic.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Trastornos del Inicio y del Mantenimiento del Sueño , Embarazo , Femenino , Humanos , Anciano , COVID-19/epidemiología , Pandemias , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Prevalencia , Depresión/epidemiología , Depresión/etiología , SARS-CoV-2 , Ansiedad/epidemiología , Ansiedad/etiología , Factores de Riesgo , Enfermedades Transmisibles/epidemiología
20.
Inorg Chem ; 62(18): 7032-7044, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37120844

RESUMEN

Polynuclear molecular clusters offer an opportunity to design new hierarchical switchable materials with collective properties, based on variation of the chemical composition, size, shapes, and overall building blocks organization. In this study, we rationally designed and constructed an unprecedented series of cyanido-bridged nanoclusters realizing new undecanuclear topology: FeII[FeII(bzbpen)]6[WV(CN)8]2[WIV(CN)8]2·18MeOH (1), NaI[CoII(bzbpen)]6[WV(CN)8]3[WIV(CN)8]·28MeOH (2), NaI[NiII(bzbpen)]6[WV(CN)8]3[WIV(CN)8]·27MeOH (3), and CoII[CoII(R/S-pabh)2]6[WV(CN)8]2[WIV(CN)8]2·26MeOH [4R and 4S; bzbpen = N1,N2-dibenzyl-N1,N2-bis(pyridin-2-ylmethyl)ethane-1,2-diamine; R/S-pabh = (R/S)-N-(1-naphthyl)-1-(pyridin-2-yl)methanimine], of size up to 11 nm3, ca. 2.0 × 2.2 × 2.5 nm (1-3) and ca. 1.4 × 2.5 × 2.5 nm (4). 1, 2, and 4 exhibit site selectivity for the spin states and spin transition related to the structural speciation based on subtle exogenous and endogenous effects imposed on similar but distinguishable 3d metal-ion-coordination moieties. 1 exhibits a mid-temperature-range spin-crossover (SCO) behavior that is more advanced than the previously reported SCO clusters based on octacyanidometallates and an onset of SCO behavior close to room temperature. The latter feature is also present in 2 and 4, which suggests the emergence of CoII-centered SCO not observed in previous bimetallic cyanido-bridged CoII-WV/IV systems. In addition, reversible switching of the SCO behavior in 1 via a single-crystal-to-single-crystal transformation during desolvation was also documented.

SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda