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1.
Abdom Radiol (NY) ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39096392

RESUMO

PURPOSE: To evaluate the diagnostic performance of radiomics models derived from multi-phase spleen CT for high-risk esophageal varices (HREV) in cirrhotic patients. METHODS: We retrospectively selected cirrhotic patients with esophageal varices from two hospitals from September 2019 to September 2023. Patients underwent non-contrast and contrast-enhanced CT scans and were categorized into HREV and non-HREV groups based on endoscopic evaluations. Radiomics features were extracted from spleen CT images in non-contrast, arterial, and portal venous phases, with feature selection via lasso regression and Pearson's correlation. Ten machine learning models were developed to diagnose HREV, evaluated by area under the curve (AUC). The AUC values of the three groups of models were statistically compared by the Kruskal-Wallis H test and Bonferroni-corrected Mann-Whitney U test. A p-value less than 0.05 was considered statistically significant. RESULTS: Among 233 patients, 11, 6, and 11 features were selected from non-contrast, arterial, and portal venous phases, respectively. Significant differences in AUC values were observed across phases (p < 0.05), and the arterial phase models showed the highest AUC values. The best model in arterial phase was the logical regression model, whose AUC value was 0.85, sensitivity was 83.3%, specificity was 80% and F1 score was 0.81. CONCLUSION: Radiomics models based on spleen CT, especially the arterial phase models, demonstrate high diagnostic accuracy for HREV, offering the potential for early detection and intervention.

2.
Front Psychol ; 15: 1412840, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947912

RESUMO

In competitive sports, momentum encompasses positive or negative changes in cognition, physiology, emotions, and behavior caused by sudden or a series of continuous events. Momentum occurring during basketball games leads to significant performance variation regarding positive net points differences for a specific team within a certain period. This study designed a quantitative framework based on two performative dimensions (time constraints and point differentials) to accurately identify momentum in basketball games, and explored the role of momentum in games. We identified 2,083 momentum occurrences in 372 professional elite basketball games. The number of momentum occurrences for winning teams is significantly higher than for losing teams (1.78 ± 0.47 Difference Value, p < 0.001); the correlation between momentum and game outcomes decreased as each quarter progressed. To distinguish the influence of contextual variables on momentum, we divided games into five types based on the team quality differences between the team and the opponent team. The decision tree model shows that first-quarter momentum is critical in games where weaker teams defeat stronger teams. This study provides insights for basketball coaches to formulate game strategies. More importantly, the momentum conceptual framework can help researchers identify and capture momentum, offering inspiration and reference for subsequent research.

3.
Acad Radiol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38997882

RESUMO

RATIONALE AND OBJECTIVES: To explore the value of splenic hemodynamic parameters from low-dose one-stop dual-energy and perfusion CT (LD-DE&PCT) in non-invasively predicting high-risk esophageal varices (HREV) in cirrhotic patients. METHODS: We retrospectively analyzed cirrhotic patients diagnosed with esophageal varices (EV) through clinical, laboratory, imaging, and endoscopic examinations from September 2021 to December 2023 in our hospital. All patients underwent LD-DE&PCT to acquire splenic iodine concentration and perfusion parameters. Radiation dose was recorded. Patients were classified into non-HREV and HREV groups based on endoscopy. Univariate and multivariate logistic regression analysis were performed, and the prediction model for HREV was constructed. P < 0.05 was considered statistically significant. RESULTS: Univariate analysis revealed that significant differences were found in portal iodine concentration (PIC), blood flow (BF), permeability surface (PS), spleen volume (V-S), total iodine concentration (TIC), and total blood volume of the spleen (BV-S) between groups. TIC demonstrated the highest predictive value with an area under the curve (AUC) value of 0.87. Multivariate analysis showed that PIC, PS, and BV-S were independent risk factors for HREV. The logistic regression model for predicting HREV had an AUC of 0.93. The total radiation dose was 20.66 ± 4.07 mSv. CONCLUSION: Splenic hemodynamic parameters obtained from LD-DE&PCT can non-invasively and accurately assess the hemodynamic status of the spleen in cirrhotic patients with EV and predict the occurrence of HREV. Despite the retrospective study design and limited sample size of this study, these findings deserve further validation through prospective studies with larger cohorts.

4.
Neurosurgery ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860769

RESUMO

BACKGROUND AND OBJECTIVES: This study aimed to investigate the clinical, radiological, pathological features, treatment options, and outcomes of isocitrate dehydrogenase (IDH)-mutant brainstem gliomas (BSG-IDHmut). METHODS: A retrospective analysis of 22 patients diagnosed with BSG-IDHmut and treated at our institution from January 2011 to January 2017 was performed. Their clinical, radiological data, and long-term outcomes were collected and analyzed. RESULTS: The median age of patients was 38.5 years, with a male predominance (63.6%). All patients had IDH1 and TP53 mutations, with noncanonical IDH mutations in 59.1% of cases, 06-methylguanine-DNA methyltransferase promoter methylation in 55.6%, and alpha-thalassemia mental retardation X-linked loss in 63.2%, respectively. Tumors were primarily located in the pontine-medullary oblongata (54.5%) and frequently involved the pontine brachium (50%). Most tumors exhibited ill-defined boundaries (68.2%), no T2-FLAIR mismatch (100%), and no contrast enhancement (86.3%). Two radiological growth patterns were also identified: focal and extensively infiltrative, which were associated with the treatment strategy when tumor recurred. Seven patients (31.8%) received surgery only and 15 (68.2%) surgery plus other therapy. The median overall survival was 124.8 months, with 1-year, 2-year, 5-year, and 10-year survival rates of 81.8%, 68.2%, 54.5%, and 13.6%, respectively. Six patients experienced tumor recurrence, and all retained their radiological growth patterns, with 2 transformed into central nervous system World Health Organization grade 4. CONCLUSION: BSG-IDHmut represents a unique subgroup of brainstem gliomas with distinctive features and more favorable prognosis compared with other brainstem gliomas. Further research is required to better understand the molecular mechanisms and optimize treatment strategies for this rare and complex disease.

5.
Chempluschem ; : e202400270, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752655

RESUMO

Metallo-supramolecular polymer networks (MSPNs) are fabricated from the crosslinking of polymers by discrete supramolecular coordination complexes. Due to the availability of various coordination complexes, e. g., 2D macrocycles and 3D nanocages, the MSPNs have been recently developed with broadly tunable visco-elasticity and enriched functions inherited from the coordination complexes. The coordination complexes possess enriched topologies and unique structural relaxation dynamics, rendering them the capability to break the traditional tradeoffs of polymer systems for the design of materials with enhanced mechanical performance. The structure-property relationship studies are critical for the material-by-design of MSPNs, while the spatiotemporal investigations are desired for the exploration of dynamics information. The work summarizes recent studies on the unique ligand-exchange kinetics and the multi-level structural relaxation dynamics of MSPNs. The MSPNs' mechanical properties can be quantitatively correlated with the dynamics for understanding the structure-property relationship. This concept will not only serve to attract more researchers to engage in the study of the structure-activity relationship of MSPNs but also inspire innovative research findings pertaining to the application of MSPNs.

6.
Microorganisms ; 12(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38792846

RESUMO

Both pandemic and seasonal influenza are major health concerns, causing significant mortality and morbidity. Current influenza drugs primarily target viral neuraminidase and RNA polymerase, which are prone to drug resistance. Polyoxometalates (POMs) are metal cation clusters bridged by oxide anions. They have exhibited potent anti-tumor, antiviral, and antibacterial effects. They have remarkable activity against various DNA and RNA viruses, including human immunodeficiency virus, herpes simplex virus, hepatitis B and C viruses, dengue virus, and influenza virus. In this study, we have identified sodium polyoxotungstate (POM-1) from an ion channel inhibitor library. In vitro, POM-1 has been demonstrated to have potent antiviral activity against H1N1, H3N2, and oseltamivir-resistant H1N1 strains. POM-1 can cause virion aggregation during adsorption, as well as endocytosis. However, the aggregation is reversible; it does not interfere with virus adsorption and endocytosis. Our results suggest that POM-1 exerts its antiviral activity by inhibiting the nuclear import of viral ribonucleoprotein (vRNP). This distinct mechanism of action, combined with its wide range of efficacy, positions POM-1 as a promising therapeutic candidate for influenza treatment and warrants further investigation.

7.
Neuropsychiatr Dis Treat ; 20: 937-946, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751379

RESUMO

Objective: This study aims to explore the nexus between students' psychological well-being and the manifestation of gastrointestinal symptoms (GISs) amid the health lockdown enforced in Xi'an, focusing on the student populace of Xi'an Medical College and Shaanxi University of Traditional Chinese Medicine. Materials and methods: A survey encompassing psychological parameters and GISs was administered to a randomized cohort of 1327 college students drawn from Xi'an Medical College and Shaanxi University of Traditional Chinese Medicine. The survey instrument was developed utilizing the Questionnaire Star platform. Subsequent to data collection, analysis was performed using GraphPad Prism 9 and SPSS 22.0. Results: Comparative analysis revealed statistically significant disparities (P < 0.05) in various GISs between the periods during and preceding the health lockdown, encompassing symptoms such as nausea/vomiting, acid reflux, postprandial fullness/early satiety, anorexia, decreased appetite, bloating, abdominal discomfort, abdominal pain, diarrhea, and constipation. Notably, the mean score for Generalized Anxiety Disorder 7 (GAD-7) was 3.31±3.92, indicating mild anxiety, while the mean score for Patient Health Questionnaire-2 (PHQ-2) was 1.15±1.28, suggesting mild depression. Detailed evaluation of anxiety revealed prevalence rates of 34% among respondents, with 34.2% of these individuals reporting concurrent GISs, while among those evaluated for depression (38.8% of the sample), 44.2% reported concurrent GISs. Furthermore, multiple linear regression analysis unveiled a negative correlation between GISs during the health lockdown and lifestyle scores, while positive correlations were observed with GISs preceding the lockdown, anxiety, and depression. The formulated multiple linear regression equation for GISs during the health lockdown is delineated as follows: 14.693-0.342 life style + 0.725GISs before health lockdown + 0.218anxiety + 0.564 depression. Conclusion: This investigation underscores the substantial impact of anxiety and depression on the student body, accentuating their role in precipitating GISs during health lockdown situations. The psychological well-being of medical students during exigent circumstances such as natural disasters warrants heightened attention, necessitating proactive measures aimed at emotional regulation to mitigate the onset of GISs.

8.
Adv Sci (Weinh) ; 11(28): e2404073, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757622

RESUMO

Ferroptosis plays important roles both in normal physiology and multiple human diseases. It is well known that selenoprotein named glutathione peroxidase 4 (GPX4) is a crucial regulator for ferroptosis. However, it remains unknown whether other selenoproteins responsible for the regulation of ferroptosis, particularly in gut diseases. In this study, it is observed that Selenoprotein I (Selenoi) prevents ferroptosis by maintaining ether lipids homeostasis. Specific deletion of Selenoi in intestinal epithelial cells induced the occurrence of ferroptosis, leading to impaired intestinal regeneration and compromised colonic tumor growth. Mechanistically, Selenoi deficiency causes a remarkable decrease in ether-linked phosphatidylethanolamine (ePE) and a marked increase in ether-linked phosphatidylcholine (ePC). The imbalance of ePE and ePC results in the upregulation of phospholipase A2, group IIA (Pla2g2a) and group V (Pla2g5), as well as arachidonate-15-lipoxygenase (Alox15), which give rise to excessive lipid peroxidation. Knockdown of PLA2G2A, PLA2G5, or ALOX15 can reverse the ferroptosis phenotypes, suggesting that they are downstream effectors of SELENOI. Strikingly, GPX4 overexpression cannot rescue the ferroptosis phenotypes of SELENOI-knockdown cells, while SELENOI overexpression can partially rescue GPX4-knockdown-induced ferroptosis. It suggests that SELENOI prevents ferroptosis independent of GPX4. Taken together, these findings strongly support the notion that SELENOI functions as a novel suppressor of ferroptosis during colitis and colon tumorigenesis.


Assuntos
Colite , Neoplasias Colorretais , Ferroptose , Selenoproteínas , Ferroptose/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Camundongos , Animais , Selenoproteínas/metabolismo , Selenoproteínas/genética , Colite/metabolismo , Colite/genética , Humanos , Modelos Animais de Doenças , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Transdução de Sinais/genética
9.
J Med Virol ; 96(4): e29592, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587184

RESUMO

The role of human papillomavirus 16 (HPV 16) in esophageal squamous cell carcinoma (ESCC) remains uncertain. Therefore, this study aimed to investigate the prevalence of HPV 16 in patients with ESCC and its impact on theirprognosis. HPV 16 was detected using FISH, and TP53 status was evaluated via immunohistochemistry. The factors influencing prognosis were ananalyzed using the Log-rank test and Cox regression analyses. Among 178 patients with ESCC, 105 and 73 patients were categorized into concurrent chemoradiotherapy (CCRT) and postoperative chemoradiotherapy (POCRT) cohorts, respectively. Among 178 patients, 87 (48.87%) tested positive for HPV 16. Log-rank tests revealed that the overall survival (OS) of patients with ESCC who were HPV 16-positive was longer than that of those who were HPV 16-negative (median OS: 57 months vs. 27 months, p < 0.01**). HPV 16 infection and TP53 mutation status were identified as independent events. The OS of patients with mutant TP53 who were HPV 16-positive was longer than that of those who were HPV 16-negative in both CCRT and POCRT cohorts (p = 0.002** for CCRT cohorts and p = 0.0023** for POCRT cohorts). Conversely, HPV 16 infection had no effect on OS in the wild-type TP53 subgroup (p = 0.13 and 0.052 for CCRT and POCRT cohorts, respectively). As a conclusion, the positive rate of HPV 16 in ESCC in this study was 48.87% (87/178). Among the patients with ESCC who had TP53 mutation, those who were HPV 16-positive exhibited a better prognosis than those who were HPV 16-negative.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas do Esôfago/radioterapia , Papillomavirus Humano 16/genética , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/patologia , Estudos Retrospectivos , Quimiorradioterapia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia
10.
Heliyon ; 10(7): e29099, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38617932

RESUMO

Background: ARF family proteins are a kind of small GTPases, which are involved in regulating a variety of basic functions of cells. In recent years, the role and molecular regulatory mechanisms of ARFs in tumor progression have received increasing attention, and research reports on most of their family members are increasing. However, research on the clinical and pathological relevance of ARF5 in cancer, especially in hepatocellular carcinoma, still needs to be improved. Methods: RNA-seq data in the Cancer Genome Atlas (TCGA) and genome tissue expression (GTEx) databases were used to analyze the expression and pathological data of ARFs family in Pan-cancer. Kaplan-Meier and Cox regression were used for prognostic analysis of ARF5 and Pan-cancer. Combined with ImmuCellAI database and TIMER2 database, the relationship between ARF5 expression and immune cell tumor infiltration in hepatocellular carcinoma (HCC) was analyzed. WGCNA is used to construct the co-expression gene network related to ARF5 expression in HCC and screen important modules and central genes. GO and KEGG path enrichment analysis were carried out for the genes in the modules with clinical significance. GSEA analysis was performed to take into account the role of genes with small differences. Finally, ceRNA network analysis was used to explore the molecular mechanism of miRNAs and lncRNAs regulating ARF5 expression. Results: ARFs family (ARF1, ARF3, ARF4, ARF5, ARF6) are generally highly expressed in Pan-cancer. ARF5 is significantly highly expressed in 29 cancers, and the high expression of ARF5 in HCC patients is significantly negatively correlated with OS, DFI, PFI and DSS, which may lead to cancer deterioration by participating in tumor immune infiltration of HCC. Through WGCNA analysis, the expression of ARF5 in HCC may be involved in many cellular processes that consume a lot of energy, such as ribosome formation, RNA and protein synthesis and lipids, as well as COVID-19, nonalcoholic fatty liver, neurodegenerative diseases and other disease pathways. Conclusion: ARFs, especially ARF5, are overexpressed in many human tumors. This study shows for the first time that ARF5 is significantly correlated with the poor prognosis of HCC patients, which may play a role as an oncogene, suggesting that ARF5 has the potential as a biomarker for the diagnosis and treatment of HCC.

11.
Int J Biol Macromol ; 267(Pt 2): 131325, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604425

RESUMO

Black rice anthocyanins (BRA) nanoparticles (NPs) were prepared using hyaluronic acid (HA), oxidized hyaluronic acid (OHA) and bovine serum albumin (BSA) to enhance the absorption and bioactivity of anthocyanins (ACNs). Results showed that HA/OHA-BSA-BRA NPs had a spherical morphology and excellent dispensability, with hydrated radius ~ 500 nm, zeta potential ~ - 30 mV, and encapsulation efficiency ~21 %. Moreover, using in vitro gastrointestinal release assay, we demonstrated that both BRA-loaded NPs exhibited effective controlled release properties of ACNs, significantly enhancing the accessibility of ACNs to the intestine. Cellular experiments showed that both two NPs had good biocompatibility and increased uptake of BRA. Furthermore, in comparison to the free BRA group, both BRA NPs groups significantly decreased the TEER value and increased the expression of tight junction proteins (Claudin 1, Occludin and ZO-1) in Caco-2 cell monolayers with LPS-induced damage. Therefore, our study demonstrated that HA/OHA-BSA-BRA NPs are promising carriers of ACNs and can effectively prevent the LPS-induced intestinal barrier injury in vitro.


Assuntos
Antocianinas , Ácido Hialurônico , Nanopartículas , Oryza , Soroalbumina Bovina , Humanos , Antocianinas/farmacologia , Antocianinas/química , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Nanopartículas/química , Células CACO-2 , Soroalbumina Bovina/química , Oryza/química , Animais , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Bovinos , Portadores de Fármacos/química , Função da Barreira Intestinal
12.
Adv Mater ; 36(27): e2401118, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38641859

RESUMO

As an empirical tool in materials science and engineering, the iconic phase diagram owes its robustness and practicality to the topological characteristics rooted in the celebrated Gibbs phase law free variables (F) = components (C) - phases (P) + 2. When crossing the phase diagram boundary, the structure transition occurs abruptly, bringing about an instantaneous change in physical properties and limited controllability on the boundaries (F = 1). Here, the sharp phase boundary is expanded to an amorphous transition region (F = 2) by partially disrupting the long-range translational symmetry, leading to a sequential crystalline-amorphous-crystalline (CAC) transition in a pressurized In2Te5 single crystal. Through detailed in situ synchrotron diffraction, it is elucidated that the phase transition stems from the rotation of immobile blocks [In2Te2]2+, linked by hinge-like [Te3]2- trimers. Remarkably, within the amorphous region, the amorphous phase demonstrates a notable 25% increase of the superconducting transition temperature (Tc), while the carrier concentration remains relatively constant. Furthermore, a theoretical framework is proposed revealing that the unconventional boost in amorphous superconductivity might be attributed to an intensified electron correlation, triggered by a disorder-augmented multifractal behavior. These findings underscore the potential of disorder and prompt further exploration of unforeseen phenomena on the phase boundaries.

13.
Bioact Mater ; 36: 203-220, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38463553

RESUMO

Ulcerative colitis (UC) is characterized by chronic inflammatory processes of the intestinal tract of unknown origin. Current treatments lack understanding on how to effectively alleviate oxidative stress, relieve inflammation, as well as modulate gut microbiota for maintaining intestinal homeostasis synchronously. In this study, a novel drug delivery system based on a metal polyphenol network (MPN) was constructed via metal coordination between epigallocatechin gallate (EGCG) and Fe3+. Curcumin (Cur), an active polyphenolic compound, with distinguished anti-inflammatory activity was assembled and encapsulated into MPN to generate Cur-MPN. The obtained Cur-MPN could serve as a robust reactive oxygen species modulator by efficiently scavenging superoxide radical (O2•-) as well as hydroxyl radical (·OH). By hitchhiking yeast microcapsule (YM), Cur-MPN was then encapsulated into YM to obtain CM@YM. Our findings demonstrated that CM@YM was able to protect Cur-MPN to withstand the harsh gastrointestinal environment and enhance the targeting and retention abilities of the inflamed colon. When administered orally, CM@YM could alleviate DSS-induced colitis with protective and therapeutic effects by scavenging ROS, reducing pro-inflammatory cytokines, and regulating the polarization of macrophages to M1, thus restoring barrier function and maintaining intestinal homeostasis. Importantly, CM@YM also modulated the gut microbiome to a favorable state by improving bacterial diversity and transforming the compositional structure to an anti-inflammatory phenotype as well as increasing the content of short-chain fatty acids (SCFA) (such as acetic acid, propionic acid, and butyric acid). Collectively, with excellent biocompatibility, our findings indicate that synergistically regulating intestinal microenvironment will be a promising approach for UC.

14.
Small ; 20(29): e2311527, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38334257

RESUMO

Stretchable organic transistors for skin-like biomedical applications require low-voltage operation to accommodate limited power supply and safe concerns. However, most of the currently reported stretchable organic transistors operate at relatively high voltages. Decreasing their operational voltage while keeping the high mobility still remains a key challenge. Here, the study presents a new dielectric design to achieve high-dielectric constant poly(urea-urethane) (PUU) elastomer, by incorporating a flexible small-molecular diamine crosslinking agent 4-aminophenyl disulfide (APDS) into the main chain of (poly (propylene glycol), tolylene 2,4-diiso-cyanate terminated) (PPG-TDI). Compared with commercial elastomers, the PUU elastomer as dielectric of the stretchable organic transistors shows the outstanding advantages including lower surface roughness (0.33 nm), higher adhesion (45.18 nN), higher dielectric constant (13.5), as well as higher stretchability (896%). The PUU dielectric enables the intrinsically stretchable, all-solution-processed organic transistor to operate at a low operational voltage down to -10 V, while preserving a substantial mobility of 1.39 cm2 V-1 s-1. Impressively, the transistor also demonstrates excellent electrical stability under repeated switching of 10 000 cycles, and remarkable mechanical robustness when stretched up to 100%. The work opens up a new molecular engineering strategy to successfully realize low-voltage high-mobility stretchable all-solution-processed organic transistors.

15.
Carbohydr Polym ; 327: 121646, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171671

RESUMO

Achieving excellent ultraviolet (UV) blocking properties and maintaining high light transmittance are highly challenging. In this study, a facile and green polymer-assisted vacuum filtration strategy was used to prepare cellulose nanocrystal (CNC) one-dimensional photonic crystal (1DPhC) films with excellent UV-blocking performance and good transparency. The polymer-assisted self-assembly behaviors of CNC and the hydrogen bonding interaction between CNC, polyethylene glycol (PEG), and graphene oxide (GO) drive the homogeneous distribution and parallel alignment of GO. The UV absorption of GO and high reflection of UV resulting from the chiral nematic structure of CNCs result in excellent UV-blocking and high visible light transmission. Besides, the strong hydrogen bonding interaction among CNC, PEG, and GO endows the films with obviously increased mechanical properties. The UV-blocking and the transparency of the CNC composite films could reach 98.3 % and 60.5 %, respectively. Besides, the strain at break of the composite film reached 1.72 ± 0.11 %, which was 535.94 % of neat CNC films. The CNC composite films present great potential in the field of UV-blocking glass, sensors, anti-counterfeiting measures, radiation protection, and so on.

16.
J Am Chem Soc ; 146(5): 3553-3563, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38285529

RESUMO

Flexible membranes with ultrathin thickness and excellent mechanical properties have shown great potential for broad uses in solid polymer electrolytes (SPEs), on-skin electronics, etc. However, an ultrathin membrane (<5 µm) is rarely reported in the above applications due to the inherent trade-off between thickness and antifailure ability. We discover a protic solvent penetration strategy to prepare ultrathin, ultrastrong layered films through a continuous interweaving of aramid nanofibers (ANFs) with the assistance of simultaneous protonation and penetration of a protic solvent. The thickness of a pure ANF film can be controlled below 5 µm, with a tensile strength of 556.6 MPa, allowing us to produce the thinnest SPE (3.4 µm). The resultant SPEs enable Li-S batteries to cycle over a thousand times at a high rate of 1C due to the small ionic impedance conferred by the ultrathin characteristic and regulated ionic transportation. Besides, a high loading of the sulfur cathode (4 mg cm-2) with good sulfur utilization was achieved at a mild temperature (35 °C), which is difficult to realize in previously reported solid-state Li-S batteries. Through a simple laminating process at the wet state, the thicker film (tens of micrometers) obtained exhibits mechanical properties comparable to those of thin films and possesses the capability to withstand high-velocity projectile impacts, indicating that our technique features a high degree of thickness controllability. We believe that it can serve as a valuable tool to assemble nanomaterials into ultrathin, ultrastrong membranes for various applications.

17.
Nano Lett ; 24(5): 1753-1760, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38287247

RESUMO

Polymer based low evaporation enthalpy materials have become a universal selection for improving the efficiency of solar steam generation. Although water cluster and intermediate water mechanisms have been proposed to explain the low evaporation enthalpy, the production process and microstructure of activated water are still unclear. Here, crystal plane engineering is used to investigate the intermediate water state and the water cluster activation mechanism. The unique open-closed coordination structure on the optimized crystal surface promotes the generation of firm water clusters by optimizing the intermediate water state. Under the similar solar energy absorption of all materials, crystal plane engineering increased the solar steam generation rate of the evaporator by 31.2% and increased the energy efficiency to 94.8%. Exploring the micro-evaporation process and activated water structure is expected to stimulate the development of the next generation low evaporation enthalpy materials.

18.
Plants (Basel) ; 13(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276773

RESUMO

The volatile compounds produced by plants play an important role in plant growth, plant communication, and resistance to biological and abiotic stresses. Astragalus membranaceus var. mongholicus (AM) is a perennial herbaceous plant (Leguminosae) that is widely cultivated in northwest China. The bioactive compounds in its root have shown various pharmacological activities. Root rot disease caused by Fusarium spp. often occurs in AM planting with increasing severity in continuous monoculture. It is currently still unclear what are the effects of the volatile compounds produced by fresh AM on itself, other crops cultivated on the same field after AM, pathogen, and rhizobia. In this study, we found that seed germination and seedling growth of AM, lettuce (Lactuca sativa L.), and wheat (Triticum aestivum L.) could be affected if they were in an enclosed space with fresh AM tissue. Additionally, 90 volatile compounds were identified by SPME-GC-MS from whole AM plant during the vegetative growth, 36 of which were specific to aerial parts of AM (stems and leaves, AMA), 17 to roots (AMR), and 37 were found in both AMA and AMR. To further identify the allelopathic effects of these volatile compounds, five compounds (1-hexanol, (E)-2-hexenal, (E,E)-2,4-decadienal, hexanal, and eugenol) with relatively high content in AM were tested on three receptor plants and two microorganisms. We found that (E,E)-2,4-decadienal and (E)-2-hexenal showed significant inhibitory effects on the growth of AM and lettuce. One-hexanol and hexanal suppressed the growth of wheat, while eugenol showed a similar effect on all three plant species. Moreover, the activities of these compounds were dose dependent. Notably, we discovered that (E)-2-hexenal and eugenol also inhibited the growth of the pathogen Fusarium solani by as high as 100%. Meanwhile, all five compounds tested suppressed the rhizobia Sinorhizobium fredii. In summary, this study furthered our understanding of the comprehensive allelopathic effects of the main volatile components of AM.

19.
J Neurosurg ; 140(6): 1527-1539, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134425

RESUMO

OBJECTIVE: Surgery for midbrain pilocytic astrocytoma (PA) remains a formidable challenge. To facilitate decision-making and achieve a better outcome in the management of patients with midbrain PA, the authors have proposed a novel radiological classification of midbrain PAs with long-term follow-up. METHODS: Fifty-seven midbrain PA patients who underwent surgery at Beijing Tiantan Hospital, Capital Medical University, from January 2008 to June 2021, were reviewed. Based on tumor location and the topological anatomical change identified on MRI, midbrain PAs were categorized into four types: crural (12/57, 21.1%), tegmental (25/57, 43.9%), aqueductal (5/57, 8.8%), and tectal (15/57, 26.3%) PAs. The relevant clinical, radiological, and pathological data; surgical procedures and results; and long-term outcomes were collected and analyzed. RESULTS: The 1-, 3-, and 5-year survival rates reached 98%, 96%, and 96%, respectively, with gross-total resection achieved in 66.7% of cases, followed by near-total resection in 17.5% cases. The clinical and radiological features, selection of surgical approaches, and long-term postoperative deficits were distinct among each type. Crural PAs were associated with younger age (median 9 years, IQR 5.0-12.8 years); the largest tumor volume (median 31.9 cm3, IQR 17.2-42.6 cm3); the lowest preoperative Karnofsky Performance Scale (KPS) score (median 65, IQR 50-70); the most frequent preoperative motor deficit (91.7%); a mixed solid-cystic component (75%); occupation of the crural cistern; elevation and rotation of the thalamus (medial and/or lateral); displacement of the anterior third ventricle, uncus, and anterior commissure; the most diverse surgical approaches; more frequent use of multimodality image-guided surgery (58.3%); and the most remarkable improvement in KPS score at long-term follow-up. Tegmental PAs were associated with adolescents and young adults (median age 21 years, IQR 8-33 years); tumor volume (median 13.9 cm3, IQR 9.5-20.5 cm3); a good preoperative KPS score (median 80, IQR 70-80); a mixed solid-cystic component (72%); occupation of the ambient cistern and cerebellomesencephalic fissure; a close relationship with the dorsal pons, superior cerebellar peduncle, and posterior inferior third ventricle; and a higher probability of permanent postoperative sensory deficits (40%). Aqueductal and tectal PAs were associated with small tumor volume (median 9.14 cm3, IQR 5.1-17.4 cm3 and median 11.84 cm3, IQR 5.7-18.3 cm3, respectively), a higher percentage of hydrocephalus (80% and 86.7%, respectively), and a straightforward selection of limited surgical approaches. CONCLUSIONS: A novel and comprehensive radiological classification of midbrain PAs was established, which will serve as a valuable tool in patient management and promote uniform communication and comparison across different studies and publications.


Assuntos
Astrocitoma , Imageamento por Ressonância Magnética , Mesencéfalo , Procedimentos Neurocirúrgicos , Humanos , Astrocitoma/cirurgia , Astrocitoma/diagnóstico por imagem , Astrocitoma/patologia , Masculino , Feminino , Adulto , Adolescente , Criança , Adulto Jovem , Mesencéfalo/diagnóstico por imagem , Mesencéfalo/cirurgia , Mesencéfalo/patologia , Procedimentos Neurocirúrgicos/métodos , Pessoa de Meia-Idade , Pré-Escolar , Estudos Retrospectivos , Neoplasias do Tronco Encefálico/cirurgia , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/patologia , Resultado do Tratamento , Seguimentos
20.
Proc Natl Acad Sci U S A ; 121(1): e2307395120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38157451

RESUMO

Oxidative stress, which can be activated by a variety of environmental risk factors, has been implicated as an important pathogenic factor for inflammatory bowel disease (IBD). However, how oxidative stress drives IBD onset remains elusive. Here, we found that oxidative stress was strongly activated in inflamed tissues from both ulcerative colitis patients and Crohn's disease patients, and it caused nuclear-to-cytosolic TDP-43 transport and a reduction in the TDP-43 protein level. To investigate the function of TDP-43 in IBD, we inducibly deleted exons 2 to 3 of Tardbp (encoding Tdp-43) in mouse intestinal epithelium, which disrupted its nuclear localization and RNA-processing function. The deletion gave rise to spontaneous intestinal inflammation by inducing epithelial cell necroptosis. Suppression of the necroptotic pathway with deletion of Mlkl or the RIP1 inhibitor Nec-1 rescued colitis phenotypes. Mechanistically, disruption of nuclear TDP-43 caused excessive R-loop accumulation, which triggered DNA damage and genome instability and thereby induced PARP1 hyperactivation, leading to subsequent NAD+ depletion and ATP loss, consequently activating mitochondrion-dependent necroptosis in intestinal epithelial cells. Importantly, restoration of cellular NAD+ levels with NAD+ or NMN supplementation, as well as suppression of ALKBH7, an α-ketoglutarate dioxygenase in mitochondria, rescued TDP-43 deficiency-induced cell death and intestinal inflammation. Furthermore, TDP-43 protein levels were significantly inversely correlated with γ-H2A.X and p-MLKL levels in clinical IBD samples, suggesting the clinical relevance of TDP-43 deficiency-induced mitochondrion-dependent necroptosis. Taken together, these findings identify a unique pathogenic mechanism that links oxidative stress to intestinal inflammation and provide a potent and valid strategy for IBD intervention.


Assuntos
Doenças Inflamatórias Intestinais , Necroptose , Humanos , Animais , Camundongos , NAD/metabolismo , Estruturas R-Loop , Doenças Inflamatórias Intestinais/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Inflamação/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/metabolismo
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