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1.
Adv Ophthalmol Pract Res ; 4(3): 128-133, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952566

RESUMEN

Purpose: Aims to provide an overview of the contemporary epidemiology of malignant orbital tumors by analyzing population-based incidence patterns across various regions worldwide. Methods: In this article, we retrieved orbital malignancy data from the MEDLINE database and analyzed the incidence and prevalence of orbital malignancies worldwide. We performed the literature search by searching on the Mesh terms for malignant orbital tumors ("orbital", "tumor", "lymphoma", "malignant", "cancer", "incidence", and "epidemiology"). All included studies were published between 1993 and 2023 and were written in English. Results: Ocular or ophthalmic lymphoma most frequently occurred in the orbit, with a prevalence ranging from 47% to 54%. The incidence of malignant orbital tumors was increasing in the USA (2.0 per million (1981-1993), Netherlands (0.86 (1981-1985) to 2.49 (2001-2005) per million) and South Korea (0.3-0.8 per million (1999-2016)), respectively. Ophthalmic lymphoma which includes orbit lymphoma was increasing in Canada (0.17-1.47 per million (1992-2010)), Denmark (0.86 per million (1981-1985) to 2.49 per million (2001-2005)), respectively. Conclusions: The predominant primary malignant orbital tumor in adults was lymphoma. Ocular or ophthalmic lymphoma most frequently occured in the orbit. The limited data available suggested an increasing trend in the incidence of malignant orbital tumors in each country included, which were mainly attributed to the increase in lymphoma. Generally, incidence rates were found to increase with advancing age, with no difference between males and females.

2.
Explore (NY) ; 20(5): 103031, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38986288

RESUMEN

Neutropenia, a common side effect of chemotherapy for ovarian cancer, was observed in a 47-year-old female patient undergoing a six-cycle chemotherapy regimen. She experienced recurrent neutropenia and leukopenia but refused granulocyte colony-stimulating factor (G-CSF) due to severe bone pain and high costs. Moxibustion combined with guasha therapy (MGT) was administered each time neutropenia occurred. The treatment involved guasha therapy on the bladder meridian (BL) and the governor vessel (GV), followed by moxibustion at Zhongwan (CV 12), Guanyuan (CV 4), and Shenzhu (GV 12) points over 2-3 days. This approach led to the recovery of neutrophil and leukocyte counts, enabling the patient to complete six chemotherapy cycles without G-CSF. These findings suggest that MGT may enhance neutrophil and leukocyte counts in patients with chemotherapy-induced myelosuppression, presenting a potential alternative for those intolerant to G-CSF. However, further high-quality research is needed to confirm its efficacy.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39052060

RESUMEN

Xiatianwu is a traditional Chinese medicine. This study investigates the function of Xiatianwu in treating HCC through database analyses and in vitro experiments. The active ingredients of Xiatianwu were identified from TCMSP and HERB databases and their targets were predicted by Swiss TargetPrediction. The HCC dataset was screened using the GEO database, and the differentially expressed genes between HCC and non-tumor liver tissues were analyzed to identify overlapping targets with Xiatianwu. The intersecting targets underwent enrichment analysis using R software to elucidate the molecular mechanisms of Xiatianwu against HCC. Core targets were identified using the PPI network and MCODE algorithm. Clinical relevance and disease prognosis in HCC were verified using the TCGA database. Meanwhile, binding affinities among components and targets were validated with molecular docking. Finally, the anti-HCC efficacy of the active ingredient was validated in vitro. Our findings revealed that eight active ingredients of Xiatianwu interacted with 11 key targets, providing anti-HCC efficacy. Molecular docking indicated that bicuculline and fumarine exhibited superior binding abilities. Bicuculline, a representative ingredient of Xiatianwu, was chosen for in vitro validation. Results demonstrated that bicuculline, in a dose-dependent manner inhibited HCC cell viability, reduced migration, suppressed the G0/M cell cycle, and decreased core protein expression. Xiatianwu demonstrates significant potential for clinical application in treating HCC. Bicuculline, a key active ingredient of Xiatianwu, exerts anti-HCC effects by inhibiting the cell cycle.

4.
Sci China Life Sci ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39037697

RESUMEN

The TET family is well known for active DNA demethylation and plays important roles in regulating transcription, the epigenome and development. Nevertheless, previous studies using knockdown (KD) or knockout (KO) models to investigate the function of TET have faced challenges in distinguishing its enzymatic and nonenzymatic roles, as well as compensatory effects among TET family members, which has made the understanding of the enzymatic role of TET not accurate enough. To solve this problem, we successfully generated mice catalytically inactive for specific Tet members (Tetm/m). We observed that, compared with the reported KO mice, mutant mice exhibited distinct developmental defects, including growth retardation, sex imbalance, infertility, and perinatal lethality. Notably, Tetm/m mouse embryonic stem cells (mESCs) were successfully established but entered an impaired developmental program, demonstrating extended pluripotency and defects in ectodermal differentiation caused by abnormal DNA methylation. Intriguingly, Tet3, traditionally considered less critical for mESCs due to its lower expression level, had a significant impact on the global hydroxymethylation, gene expression, and differentiation potential of mESCs. Notably, there were common regulatory regions between Tet1 and Tet3 in pluripotency regulation. In summary, our study provides a more accurate reference for the functional mechanism of Tet hydroxymethylase activity in mouse development and ESC pluripotency regulation.

5.
Biomater Adv ; 163: 213967, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39068744

RESUMEN

The healing of skin wounds is a continuous and coordinated process, typically accompanied by microbial colonization and growth. This may result in wound infection and subsequent delay in wound healing. Therefore, it is of particular importance to inhibit the growth of microorganisms in the wound environment. In this study, magnesium hydroxide-doped polycaprolactone (PCL/MH) nanofibrous spheres were fabricated by electrospinning and electrospray techniques to investigate their effects on infected wound healing. The prepared PCL/MH nanofibrous spheres had good porous structure and biocompatibility, providing a favorable environment for the delivery and proliferation of adipose stem cells. The incorporation of MH significantly enhanced the antimicrobial properties of the spheres, in particular, the inhibition of the growth of S. aureus and E. coli. We showed that such PCL/MH nanofibrous spheres had good antimicrobial properties and effectively promoted the regeneration of infected wound tissues, which provided a new idea for the clinical treatment of infected wounds.

6.
Drug Dev Res ; 85(5): e22237, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39032059

RESUMEN

The global prevalence of RNA virus infections has presented significant challenges to public health in recent years, necessitating the expansion of its alternative therapeutic library. Due to its evolutional conservation, RNA-dependent RNA polymerase (RdRp) has emerged as a potential target for broad-spectrum antiviral nucleoside analogues. However, after over half a century of structural modification, exploring unclaimed chemical space using frequently-used structural substitution methods to design new nucleoside analogues is challenging. In this study, we explore the use of the "ring-opening" strategy to design new base mimics, thereby using these base mimics to design new nucleoside analogues with broad-spectrum antiviral activities. A total of 29 compounds were synthesized. Their activity against viral RdRp was initially screened using an influenza A virus RdRp high-throughput screening model. Then, the antiviral activity of 38a was verified against influenza virus strain A/PR/8/34 (H1N1), demonstrating a 50% inhibitory concentration (IC50) value of 9.95 µM, which was superior to that of ribavirin (the positive control, IC50 = 11.43 µM). Moreover, 38a also has inhibitory activity against coronavirus 229E with an IC50 of 30.82 µM. In addition, compounds 42 and 46f exhibit an 82% inhibition rate against vesicular stomatitis virus at a concentration of 20 µM and hardly induce cytotoxicity in host cells. This work demonstrates the feasibility of designing nucleoside analogues with "ring-opening" bases and suggests the "ring-opening" nucleosides may have greater polarity, and designing prodrugs is an important aspect of optimizing their antiviral activity. Future research should focus on enhancing the conformational restriction of open-loop bases to mimic Watson-Crick base pairing better and improve antiviral activity.


Asunto(s)
Antivirales , Diseño de Fármacos , Nucleósidos , ARN Polimerasa Dependiente del ARN , Antivirales/farmacología , Antivirales/química , Antivirales/síntesis química , Nucleósidos/química , Nucleósidos/farmacología , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Humanos , Animales , Células de Riñón Canino Madin Darby , Perros , Relación Estructura-Actividad
7.
Biomed Opt Express ; 15(5): 2753-2766, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38855654

RESUMEN

Monitoring the transition of cell states during induced pluripotent stem cell (iPSC) differentiation is crucial for clinical medicine and basic research. However, both identification category and prediction accuracy need further improvement. Here, we propose a method combining surface-enhanced Raman spectroscopy (SERS) with convolutional neural networks (CNN) to precisely identify and distinguish cell states during stem cell differentiation. First, mitochondria-targeted probes were synthesized by combining AuNRs and mitochondrial localization signal (MLS) peptides to obtain effective and stable SERS spectra signals at various stages of cell differentiation. Then, the SERS spectra served as input datasets, and their distinctive features were learned and distinguished by CNN. As a result, rapid and accurate identification of six different cell states, including the embryoid body (EB) stage, was successfully achieved throughout the stem cell differentiation process with an impressive prediction accuracy of 98.5%. Furthermore, the impact of different spectral feature peaks on the identification results was investigated, which provides a valuable reference for selecting appropriate spectral bands to identify cell states. This is also beneficial for shortening the spectral acquisition region to enhance spectral acquisition speed. These results suggest the potential for SERS-CNN models in quality monitoring of stem cells, advancing the practical applications of stem cells.

8.
Biomed Opt Express ; 15(5): 2926-2936, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38855674

RESUMEN

As one of the important organelles in the process of cell differentiation, mitochondria regulate the whole process of differentiation by participating in energy supply and information transmission. Mitochondrial pH value is a key indicator of mitochondrial function. Therefore, real-time monitoring of mitochondrial pH value during cell differentiation is of great significance for understanding cell biochemical processes and exploring differentiation mechanisms. In this study, Surface-enhanced Raman scattering (SERS) technology was used to achieve the real-time monitoring of mitochondrial pH during induced pluripotent stem cells (iPSCs) differentiation into neural progenitor cells (NPCs). The results showed that the variation trend of mitochondrial pH in normal and abnormal differentiated batches was different. The mitochondrial pH value of normal differentiated cells continued to decline from iPSCs to embryoid bodies (EB) day 4, and continued to rise from EB day 4 to the NPCs stage, and the mitochondrial microenvironment of iPSCs to NPCs differentiation became acidic. In contrast, the mitochondrial pH value of abnormally differentiated cells declined continuously during differentiation. This study improves the information on acid-base balance during cell differentiation and may provide a basis for further understanding of the changes and regulatory mechanisms of mitochondrial metabolism during cell differentiation. This also helps to improve more accurate and useful differentiation protocols based on the microenvironment within the mitochondria, improving the efficiency of cell differentiation.

9.
Materials (Basel) ; 17(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38930400

RESUMEN

This study reveals the relationship between the Cu precipitates and mechanical properties of a Cu-baring ultra-low carbon steel after two-phase zone quenching and tempering at 923 K for 0.5-2.5 h. The tensile and microstructural properties were investigated as a function of heat treatment time. The contribution of the precipitation-strengthening mechanism to yield strength was calculated. The size, morphology, and distribution of the precipitated particles were observed using TEM. As the heat treatment time increased, the strength gradually decreased and then remained stable, and the elongation gradually increased and then remained stable. Additionally, the contributions of each strengthening mechanism to the yield strength under different heat treatments were 117, 107, 102, and 89 MPa, respectively. The size and quantity of the precipitates increased with the increase in heat treatment time. After tempering for more than 2 h, the precipitates continued to coarsen, but their quantity decreased. The precipitated Cu had a 3R structure with a length of approximately 17.1 nm and a width of approximately 9.7 nm, with no twinning inside. The stacking order was ABC/ABC. The stable Cu precipitation structure was FCC, maintaining a K-S orientation relationship 11¯1FCC Cu //(0 1 1) α, 1¯10FCC Cu//[11¯1] α.

10.
EMBO Rep ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866979

RESUMEN

As a hallmark of senescent cells, the derepression of Long Interspersed Elements 1 (LINE1) transcription results in accumulated LINE1 cDNA, which triggers the secretion of the senescence-associated secretory phenotype (SASP) and paracrine senescence in a cGAS-STING pathway-dependent manner. However, transcription factors that govern senescence-associated LINE1 reactivation remain ill-defined. Here, we predict several transcription factors that bind to human LINE1 elements to regulate their transcription by analyzing the conserved binding motifs in the 5'-untranslated regions (UTR) of the commonly upregulated LINE1 elements in different types of senescent cells. Further analysis reveals that PAX5 directly binds to LINE1 5'-UTR and the binding is enhanced in senescent cells. The enrichment of PAX5 at the 5'-UTR promotes cellular senescence and SASP by activating LINE1. We also demonstrate that the longevity gene SIRT6 suppresses PAX5 transcription by directly binding to the PAX5 promoter, and overexpressing PAX5 abrogates the suppressive effect of SIRT6 on stress-dependent cellular senescence. Our work suggests that PAX5 could serve as a potential target for drug development aiming to suppress LINE1 activation and treat senescence-associated diseases.

11.
Biomed Opt Express ; 15(6): 4010-4023, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38867782

RESUMEN

The activation of astrocytes derived from induced pluripotent stem cells (iPSCs) is of great significance in neuroscience research, and it is crucial to obtain both cellular morphology and biomolecular information non-destructively in situ, which is still complicated by the traditional optical microscopy and biochemical methods such as immunofluorescence and western blot. In this study, we combined digital holographic microscopy (DHM) and surface-enhanced Raman scattering (SERS) to investigate the activation characteristics of iPSCs-derived astrocytes. It was found that the projected area of activated astrocytes decreased by 67%, while the cell dry mass increased by 23%, and the cells changed from a flat polygonal shape to an elongated star-shaped morphology. SERS analysis further revealed an increase in the intensities of protein spectral peaks (phenylalanine 1001 cm-1, proline 1043 cm-1, etc.) and lipid-related peaks (phosphatidylserine 524 cm-1, triglycerides 1264 cm-1, etc.) decreased in intensity. Principal component analysis-linear discriminant analysis (PCA-LDA) modeling based on spectral data distinguished resting and reactive astrocytes with a high accuracy of 96.5%. The increase in dry mass correlated with the increase in protein content, while the decrease in projected area indicated the adjustment of lipid composition and cell membrane remodeling. Importantly, the results not only reveal the cellular morphology and molecular changes during iPSCs-derived astrocytes activation but also reflect their mapping relationship, thereby providing new insights into diagnosing and treating neurodegenerative diseases.

12.
Gynecol Obstet Invest ; : 1-13, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38723616

RESUMEN

OBJECTIVES: This study aimed to investigate the involvement of the cell cycle-related protein centromere protein F (CENPF) in the development of ovarian cancer (OC) and explored its relationship with ferroptosis. DESIGN: The databases were analysed to identify differential expression of cell cycle-related proteins between individuals with OC and normal individuals. Immunohistochemistry and statistical analysis were conducted on ovarian tissues obtained from 40 patients with epithelial OC and 20 normal individuals. In vitro experiments were performed using SKOV3 and HEY epithelial OC cell lines. PARTICIPANTS/MATERIALS, SETTING, METHODS: The mRNA microarray dataset, consisting of GSE14001, GSE54388, GSE40595, and GSE14407, was downloaded from the Gene Expression Omnibus (GEO) database to investigate the genes associated with cell cycle regulation in OC cells. CENPF was selected as the subject of study through differential analysis.Assessed the expression of CENPF in both OC patients and normal ovarian tissues using immunohistochemistry. Lentivirus infection was employed to downregulate CENPF expression, and subsequent experiments including Cell Counting Kit-8 assay, cell cycle analysis, transwell assay, and wound-healing assay were conducted to investigate the effects of CENPF on proliferation, invasion, migration, and cell cycle regulation in OC cells. The reactive oxygen species (ROS) and the malondialdehyde (MDA) assays were performed to assess the involvement of CENPF in cellular redox reactions. Western blot analysis was conducted to examine the expression levels of ferroptosis-related proteins (GPX4, SLC7A11, DMT1, and protein 53 [p53]). RESULTS: By querying and integrating cell cycle-related genes from the GEO database, in silico analyses using The Cancer Genome Atlas database combined with immunohistochemical studies, we discovered that CENPF is upregulated in OC tissues and is related to survival. Downregulation of CENPF inhibited biological function of OC cells, increased intracellular ROS and MDA levels, and downregulated the GPX4 protein and the SLC7A11/xCT protein, but upregulated the DMT1 protein and the tumour p53 expression to induce ferroptosis. LIMITATIONS: This study did not investigate ferroptosis-related studies following CENPF overexpression, and the findings have not been validated in animal studies. CONCLUSIONS: Our findings demonstrated that the deficiency of CENPF played a crucial anti-oncogenic role in the progression of OC through the mechanism of ferroptosis.

13.
ACS Appl Mater Interfaces ; 16(15): 19472-19479, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38572784

RESUMEN

Nanomedicine-enhanced immunogenic cell death (ICD) has attracted considerable attention for its great potential in cancer treatment. Even though polyethylene glycol (PEG) is widely recognized as the gold standard for surface modification of nanomedicines, some shortcomings associated with this PEGylation, such as hindered cell endocytosis and accelerated blood clearance phenomenon, have been revealed in recent years. Notably, polysarcosine (PSar) as a highly biocompatible polymer can be finely synthesized by mild ring-opening polymerization (ROP) of sarcosine N-carboxyanhydrides (Sar-NCAs) and exhibit great potential as an alternative to PEG. In this article, PSar-b-polycamptothecin block copolymers are synthesized by sequential ROP of camptothecin-based NCAs (CPT-NCAs) and Sar-NCAs. Then, the detailed and systematic comparison between PEGylation and PSarylation against the 4T1 tumor model indicates that PSar decoration can facilitate the cell endocytosis, greatly enhancing the ICD effects and antitumor efficacy. Therefore, it is believed that this well-developed PSarylation technique will achieve effective and precise cancer treatment in the near future.


Asunto(s)
Neoplasias , Péptidos , Polietilenglicoles , Sarcosina/análogos & derivados , Humanos , Camptotecina , Muerte Celular Inmunogénica , Polímeros
14.
J Cardiothorac Surg ; 19(1): 197, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600499

RESUMEN

BACKGROUND: Left atrial myxoma during pregnancy is rare. We present three cases in order to aid in the management. CASE PRESENTATION: Three cases of left atrial myxoma during pregnancy were presented in this article. Three patients all received multidisciplinary team work and acquired good outcomes. The case 1 had no symptoms and delivered before traditional cardiac surgery. The case 2 and case 3 undergone totally endoscopic minimally invasive cardiac surgery during pregnancy. The case 3 maintained pregnancy to term and gave birth to a healthy baby via vaginal delivery. No relapse of the tumor was observed. CONCLUSIONS: The management of left atrial myxoma during pregnancy ought to be individualized and combined with the gestational age. If the diagnosis was made in the first two trimesters of pregnancy, totally endoscopic minimally invasive cardiac surgery during pregnancy would be an optimal choice. The patients can benefit from the multidisciplinary team work.


Asunto(s)
Neoplasias Cardíacas , Mixoma , Humanos , Embarazo , Femenino , Mujeres Embarazadas , Atrios Cardíacos/cirugía , Recurrencia Local de Neoplasia , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirugía , Mixoma/diagnóstico , Mixoma/cirugía
15.
Cancer Discov ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563585

RESUMEN

Glioblastoma (GBM) exhibits profound metabolic plasticity for survival and therapeutic resistance, while the underlying mechanisms remain unclear. Here, we show that GBM stem cells (GSCs) reprogram the epigenetic landscape by producing substantial amounts of phosphocreatine (PCr). This production is attributed to the elevated transcription of brain-type creatine kinase (CKB), mediated by Zinc finger E-box binding homeobox 1 (ZEB1). PCr inhibits the poly-ubiquitination of the chromatin regulator bromodomain containing protein 2 (BRD2) by outcompeting the E3 ubiquitin ligase SPOP for BRD2 binding. Pharmacological disruption of PCr biosynthesis by cyclocreatine leads to BRD2 degradation and a decrease in its targets' transcription, which inhibits chromosome segregation and cell proliferation. Notably, cyclocreatine treatment significantly impedes tumor growth and sensitizes tumors to a BRD2 inhibitor in mouse GBM models without detectable side effects. These findings highlight that high production of PCr is a druggable metabolic feature of GBM and a promising therapeutic target for GBM treatment.

16.
Ann Anat ; 254: 152239, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38432349

RESUMEN

In this manuscript, the structure of the human choroid is reviewed with emphasis of the macro- and microscopic anatomy including Bruch's membrane, choriocapillaris, Sattler's and Haller's layer, and the suprachoroid. We here discuss the development of the choroid, as well as the question of choroidal lymphatics, and further the neuronal control of this tissue, as well as the pathologic angiogenesis. Wherever possible, functional aspects of the various structures are included and reviewed.


Asunto(s)
Coroides , Humanos , Coroides/anatomía & histología , Coroides/irrigación sanguínea , Lámina Basal de la Coroides/anatomía & histología , Lámina Basal de la Coroides/patología
17.
Sci Rep ; 14(1): 6439, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499623

RESUMEN

Scanning electron microscopy (SEM) is a crucial tool for analyzing submicron-scale structures. However, the attainment of high-quality SEM images is contingent upon the high conductivity of the material due to constraints imposed by its imaging principles. For weakly conductive materials or structures induced by intrinsic properties or organic doping, the SEM imaging quality is significantly compromised, thereby impeding the accuracy of subsequent structure-related analyses. Moreover, the unavailability of paired high-low quality images in this context renders the supervised-based image processing methods ineffective in addressing this challenge. Here, an unsupervised method based on Cycle-consistent Generative Adversarial Network (CycleGAN) was proposed to enhance the quality of SEM images for weakly conductive samples. The unsupervised model can perform end-to-end learning using unpaired blurred and clear SEM images from weakly and well-conductive samples, respectively. To address the requirements of material structure analysis, an edge loss function was further introduced to recover finer details in the network-generated images. Various quantitative evaluations substantiate the efficacy of the proposed method in SEM image quality improvement with better performance than the traditional methods. Our framework broadens the application of artificial intelligence in materials analysis, holding significant implications in fields such as materials science and image restoration.

18.
Angew Chem Int Ed Engl ; 63(17): e202402969, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38407381

RESUMEN

The structure and properties of materials are determined by a diverse range of chemical bond formation and breaking mechanisms, which greatly motivates the development of selectively controlling the chemical bonds in order to achieve materials with specific characteristics. Here, an orientational intervening bond-breaking strategy is demonstrated for synthesizing ultrathin metal-organic framework (MOF) nanosheets through balancing the process of thermal decomposition and liquid nitrogen exfoliation. In such approach, proper thermal treatment can weaken the interlayer bond while maintaining the stability of the intralayer bond in the layered MOFs. And the following liquid nitrogen treatment results in significant deformation and stress in the layered MOFs' structure due to the instant temperature drop and drastic expansion of liquid N2, leading to the curling, detachment, and separation of the MOF layers. The produced MOF nanosheets with five cycles of treatment are primarily composed of nanosheets that are less than 10 nm in thickness. The MOF nanosheets exhibit enhanced catalytic performance in oxygen evolution reactions owing to the ultrathin thickness without capping agents which provide improved charge transfer efficiency and dense exposed active sites. This strategy underscores the significance of orientational intervention in chemical bonds to engineer innovative materials.

19.
J Environ Sci (China) ; 141: 225-234, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38408823

RESUMEN

Acetylacetone (AcAc) is a typical class of ß-diketones with broad industrial applications due to the property of the keto-enol isomers, but its isomerization and chemical reactions at the air-droplet interface are still unclear. Hence, using combined molecular dynamics and quantum chemistry methods, the heterogeneous chemistry of AcAc at the air-droplet interface was investigated, including the attraction of AcAc isomers by the droplets, the distribution of isomers at the air-droplet interface, and the hydration reactions of isomers at the air-droplet interface. The results reveal that the preferential orientation of two AcAc isomers (keto- and enol-AcAc) to accumulate and accommodate at the acidic air-droplet interface. The isomerization of two AcAc isomers at the acidic air-droplet interface is more favorable than that at the neutral air-droplet interface because the "water bridge" structure is destroyed by H3O+, especially for the isomerization from keto-AcAc to enol-AcAc. At the acidic air-droplet interface, the carbonyl or hydroxyl O-atoms of two AcAc isomers display an energetical preference to hydration. Keto-diol is the dominant products to accumulate at the air-droplet interface, and excessive keto-diol can enter the droplet interior to engage in the oligomerization. The photooxidation reaction of AcAc will increase the acidity of the air-droplet interface, which indirectly facilitate the uptake and formation of more keto-diol. Our results provide an insight into the heterogeneous chemistry of ß-diketones and their influence on the environment.


Asunto(s)
Pentanonas , Agua , Isomerismo , Pentanonas/química , Agua/química
20.
PLoS One ; 19(1): e0295118, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38166098

RESUMEN

BACKGROUND: As an important factor affecting personal health, anxiety has always been valued by people. Prior research has consistently shown that personality traits is associated with anxiety level,but little is known about the inner mechanism of this relationship. To fill the gap, the present research aims to explore the chain mediating role of general self-efficacy and academic burnout in the relationship between big five personality and anxiety. METHODS: This cross-sectional study was performed from September to November 2022. Self-reported questionnaires including the Big Five Personality Questionnaire, General Self-Efficacy Scale, College Student's academic burnout Scale, Generalized Anxiety Scale and demographic characteristics were distributed to 2505 college students in a university in Hebei Province, of which 2,471 were valid. Statistical analysis was carried out through SPSS26.0 and SPSS PROCESS macro. RESULTS: Results showed four of the big five personality characters (i.e., extraversion, agreeableness, conscientiousness, and openness) were negatively correlated with anxiety. Neuroticism was positively correlated with anxiety. Moreover, general self-efficacy was found to be negatively correlated with academic burnout and anxiety; academic burnout was positively correlated with anxiety. Finally, general self-efficacy and academic burnout mediated the relationship between personality traits (i.e., extraversion, agreeableness, neuroticism, openness) and anxiety. CONCLUSIONS: Personality traits (i.e., extraversion, agreeableness, neuroticism, and openness) could influence anxiety through the chain mediating effects of general self-efficacy and academic burnout. Interventions focusing on anxiety reduction may be successful in increasing general self-efficacy and decreasing students' academic burnout.


Asunto(s)
Agotamiento Profesional , Autoeficacia , Humanos , Estudios Transversales , Personalidad , Ansiedad , Neuroticismo
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