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1.
Heliyon ; 10(18): e37986, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39347390

RÉSUMÉ

Background: The composition of the gut microbiome has been recorted to be strongly associated with gestational diabetes mellitus (GDM), but mutational characterization of the microbiome in patients with GDM has been overlooked. Here, we revealed the genetic variation landscape of the gut microbiome and assessed its clinical significance in a cohort of patients with GDM. Methods: We employed a macrogenomic dataset made up of a discovery cohort of 54 cases and a validation cohort of 220 cases to screen for high-abundance microbial flora and identified single nucleotide variants (SNVs) and insertions/deletions (indels). Subsequently, we analyzed the mutation spectra of genomes of the intestinal flora by using the previously identified SNVs and identified mutation signatures. Additionally, we utilized the Random Forest algorithm to identify key differential SNVs and elucidated their biological functions and associations with the clinicopathological parameters of GDM. Results: We screened 15 key microbial flora and found that the GDM group had more SNVs and indels in the intestinal flora than the control group, with a significant increase in C > T and T > C base mutations and were more susceptible to sequence mutations. Compared to the control group, the GDM group underwent a more significant evolution, as evidenced by the presence of a unique mutational spectrum and mutational characteristics. Random Forest algorithm analysis showed that the combined characterization of five gut microbial species and 21 SNV-related markers was effective in distinguishing between GDM and control subjects in both discovery (area under the curve (AUC) = 0.86) and validation (AUC = 0.73) sets. These markers also revealed that GDM is strongly associated with sphingolipids, galactose, and proteins containing the DUF structural domain. Conclusions: The GDM intestinal flora has unique mutational features that correlate significantly with clinicopathological involvement and may be involved in the development of the disease.

2.
J Colloid Interface Sci ; 678(Pt B): 125-133, 2024 Sep 02.
Article de Anglais | MEDLINE | ID: mdl-39241443

RÉSUMÉ

Exquisitely tailoring the morphologies of photocatalysts could achieve high activities. In this study, the morphological transformation of bismuth oxyhalide (BiOX, X = Br, I and Cl) from disordered lamellae to regular flowers was facilely achieved via the use of carboxylated cellulose-derived carbon (CDC). The sphere-like structure and abundant surface functional groups of CDC induce the formation of such flower-like morphologies of BiOX/CDC, and this morphology results in a pronounced increase in surface area (e.g., the surface area of BiOBr increases from 3 to 106 m2 g-1) and porosity. Combined with the good light absorption and conductivity of CDC, the flower-like BiOX/CDC exhibited impressive photocatalytic activity under visible light. Regarding the probing Cr(VI) reduction reaction, the representative BiOBr/CDC is capable of reducing 98% of Cr(VI) within 30 min of visible-light illumination, which is markedly greater than those of pure BiOBr (6%) and CDC (16%). Likewise, BiOI/CDC and BiOCl/CDC also have decent photocatalytic Cr(VI) reduction capacities (89% for BiOI/CDC and 69% for BiOCl/CDC) under visible light in comparison with pristine BiOI (13%) and BiOCl (1.5%). This work furnishes a novel and facile approach to tune photocatalyst morphologies and sheds light on the great potential of biomass-derived carbon, which may enlighten the judicious design of photocatalysts with high efficiency.

3.
Adv Mater ; : e2410537, 2024 Sep 19.
Article de Anglais | MEDLINE | ID: mdl-39300857

RÉSUMÉ

Maximizing the catalytic activity of single-atom and nanocluster catalysts through the modulation of the interaction between these components and the corresponding supports is crucial but challenging. Herein, guided by theoretical calculations, a nanoporous bilayer WS2 Moiré superlattices (MSLs) supported Au nanoclusters (NCs) adjacent to Ru single atoms (SAs) (Ru1/Aun-2LWS2) is developed for alkaline hydrogen evolution reaction (HER) for the first time. Theoretical analysis suggests that the induced robust electronic metal-support interaction effect in Ru1/Aun-2LWS2 is prone to promote the charge redistribution among Ru SAs, Au NCs, and WS2 MSLs support, which is beneficial to reduce the energy barrier for water adsorption and thus promoting the subsequent H2 formation. As feedback, the well-designed Ru1/Aun-2LWS2 electrocatalyst exhibits outstanding HER performance with high activity (η10 = 19 mV), low Tafel slope (35 mV dec-1), and excellent long-term stability. Further, in situ, experimental studies reveal that the reconstruction of Ru SAs/NCs with S vacancies in Ru1/Aun-2LWS2 structure acts as the main catalytically active center, while high-valence Au NCs are responsible for activating and stabilizing Ru sites to prevent the dissolution and deactivation of active sites. This work offers guidelines for the rational design of high-performance atomic-scale electrocatalysts.

4.
Glob Chang Biol ; 30(7): e17423, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39010751

RÉSUMÉ

The extreme dry and hot 2015/16 El Niño episode caused large losses in tropical live aboveground carbon (AGC) stocks. Followed by climatic conditions conducive to high vegetation productivity since 2016, tropical AGC are expected to recover from large losses during the El Niño episode; however, the recovery rate and its spatial distribution remain unknown. Here, we used low-frequency microwave satellite data to track AGC changes, and showed that tropical AGC stocks returned to pre-El Niño levels by the end of 2020, resulting in an AGC sink of 0.18 0.14 0.26 $$ {0.18}_{0.14}^{0.26} $$ Pg C year-1 during 2014-2020. This sink was dominated by strong AGC increases ( 0.61 0.49 0.84 $$ {0.61}_{0.49}^{0.84} $$ Pg C year-1) in non-forest woody vegetation during 2016-2020, compensating the forest AGC losses attributed to the El Niño event, forest loss, and degradation. Our findings highlight that non-forest woody vegetation is an increasingly important contributor to interannual to decadal variability in the global carbon cycle.


Sujet(s)
Carbone , El Nino-oscillation australe , Climat tropical , Carbone/métabolisme , Carbone/analyse , Cycle du carbone , Forêts , Séquestration du carbone , Changement climatique
5.
Eur J Radiol ; 178: 111594, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38986232

RÉSUMÉ

PURPOSE: To explore the predictive value of dual-layer spectral detector CT (SDCT) quantitative parameters for determining differentiation grade, lymphovascular invasion (LVI) and perineural invasion (PNI) in colorectal adenocarcinoma (CRAC) patients. METHODS: A total of 106 eligible patients with CRAC were included in this study. Spectral parameters, including CT values at 40 and 100 keV, the effective atomic number (Zeff), the iodine concentration (IC), the slope of the spectral Hounsfield unit (HU) curve (λHU), and the normalized iodine concentration (NIC) in the arterial phase (AP) and venous phase (VP), were compared according to the differentiation grade and the status of LVI and PNI. The diagnostic accuracies of the quantitative parameters with statistical significance were determined via receiver operating characteristic (ROC) curves, and the area under the curve (AUC) was calculated. RESULTS: There were 57 males and 49 females aged 43-86 (69 ± 10) years. The measured values of the spectral quantitative parameters of the CRAC were consistent within the observer (ICC range: 0.800-0.926). The 40 keV-AP, IC-AP, NIC-AP, 40 keV-VP, and IC-VP were significantly different among the different differentiation grades in the CRAC (P = 0.040, AUC = 0.673; P = 0.035, AUC = 0.684; P = 0.031, AUC = 0.639; P = 0.044, AUC = 0.663 and P = 0.035, AUC = 0.666, respectively). A statistically significant difference was observed in 40 keV-VP, 100 keV-VP, Zeff-VP, IC-VP, and λHU-VP between LVI-positive and LVI-negative patients (P = 0.003, AUC = 0.688; P = 0.015, AUC = 0.644; P = 0.001, AUC = 0.688; P = 0.001, AUC = 0.703 and P = 0.003, AUC = 0.677, respectively). There were no statistically significant differences in the values of the spectral parameters of the PNI state of patients with CRAC (P > 0.05). CONCLUSION: The quantitative parameters of SDCT had good diagnostic efficacy in differentiating between different grades and statuses of LVI in patients with CRAC; however, SDCT did not have value for identifying the state of PNI.


Sujet(s)
Adénocarcinome , Tumeurs colorectales , Invasion tumorale , Tomodensitométrie , Humains , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Tumeurs colorectales/imagerie diagnostique , Tumeurs colorectales/anatomopathologie , Adénocarcinome/imagerie diagnostique , Adénocarcinome/anatomopathologie , Tomodensitométrie/méthodes , Adulte , Sujet âgé de 80 ans ou plus , Grading des tumeurs , Métastase lymphatique/imagerie diagnostique , Reproductibilité des résultats , Sensibilité et spécificité
6.
ACS Appl Mater Interfaces ; 16(28): 36973-36982, 2024 Jul 17.
Article de Anglais | MEDLINE | ID: mdl-38966874

RÉSUMÉ

Personal thermal management technology, which adjusts the heat exchange between the human body and the environment, can passively heat or cool the body to maintain a comfortable core temperature, thereby enhancing comfort and reducing energy consumption. However, most existing personal thermal management materials have static properties, such as fixed solar reflectance and infrared emissivity, which do not support real-time dynamic temperature regulation. Moreover, sweat accumulation on the skin surface, while contributing to temperature regulation, can significantly reduce comfort. This study constructs a unidirectional moisture-permeable intelligent thermal management fabric system to achieve superior thermal and moisture comfort in complex environments. The fabric incorporates thermochromic microcapsules into PAN nanofibers by using electrospinning technology for intelligent thermal management. Subsequent hydrophobic treatment of the fiber film surface imparts the fabric with unidirectional wetting properties. The nanofibrous structure provides intrinsic elasticity and breathability. In heating mode, the fabric's average sunlight reflectance is 42.1%, which increases to 82.2% in cooling mode, resulting in a reflectance difference of approximately 40%. The hydrophobic treatment endows the fabric with excellent moisture absorption and perspiration properties, demonstrated by a unidirectional moisture transport index of 696.63 and a perspiration evaporation rate of 5.88 mg/min. When the fabric temperature matches the ambient temperature, the photothermal conversion power difference of the Janus metafabric in two modes reaches 248.37 W m-2. Additionally, Janus metafabrics show the potential for temperature-responsive design and repeated writing applications. The outstanding wearability and dynamic spectral properties of these metafabrics open new pathways for sustainable energy, smart textiles, and thermal-moisture comfort applications.

7.
J Asthma ; : 1-9, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38833524

RÉSUMÉ

OBJECTIVE: Protein kinase C (PKC) has been implicated in the increased contraction of human airway smooth muscle cells (HASMCs) in asthma. Using the three-dimensional collagen gel contraction system, the study aimed to determine the effects of LY333531, a specific inhibitor of the PKC-ß isoform, on the contraction of tumor necrosis factor (TNF)-α-sensitized HASMCs. METHODS: Cultured HASMCs were divided into five groups: the control group received no treatment, and the cells in the TNF-α group were sensitized with 10 ng/mL TNF-α for 48 h, while TNF-α was administered to sensitize HASMCs in the presence of 0.1, 0.2, and 0.5 µM LY333531 for 48 h in the 0.1LY, 0.2LY, and 0.5LY groups, respectively. Following this, HASMCs contraction was stimulated with 1 mM acetylcholine (ACh) for up to 24 h in each group and assessed using a three-dimensional collagen gel contraction assay. Furthermore, western blot and immunofluorescence analysis were performed. RESULTS: The collagen gel contraction assay revealed that TNF-α increased the protein expression of phosphorylated PKC-ß2, CPI-17, and MLC while exacerbating ACh-induced HASMCs contraction. LY333531 significantly attenuated HASMCs contraction and downregulated the protein expression of both p-CPI-17 and p-MLC. CONCLUSIONS: At least in part by regulating CPI-17 and MLC phosphorylation, LY333531 attenuates augmented contraction of TNF-α-sensitized HASMCs in a collagen gel contraction system.

8.
Fish Shellfish Immunol ; 149: 109612, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38705548

RÉSUMÉ

SH2 domain containing inositol polyphosphate5-phosphatase-2 (SHIP2) is a member of the 5-phosphatase family, acting as a vital negative regulator of immune response in vertebrates. In the present study, a SHIP2 homologue (designed as CgSHIP2) was identified from Pacific oyster, Crassostrea gigas. There was a SH2 domain, an IPPc domain and a SAM domain in CgSHIP2. The mRNA transcripts of CgSHIP2 were widely expressed in all the tested tissues with the highest expression in haemolymph. The mRNA expressions of CgSHIP2 in haemocytes increased significantly at 6, 12, 48 and 72 h after Vibrio splendidus stimulation. The positive green signals of CgSHIP2 protein were mainly located in cytoplasm of haemocytes. After the expression of CgSHIP2 was inhibited by RNA interference, the mRNA transcripts of interleukin 17s (CgIL-17-1, CgIL-17-2, CgIL-17-3 and CgIL-17-6) in the haemocytes increased significantly at 24 h after V. splendidus stimulation, which were 8.15-fold (p < 0.001), 3.44-fold (p < 0.05), 2.15-fold (p < 0.01) and 4.63-fold (p < 0.05) compared with that in NC-RNAi group, respectively. Obvious branchial swelling and cilium shedding in gills were observed in CgSHIP2-RNAi group at 24 h after V. splendidus stimulation. The results suggested that CgSHIP2 played an important role in controlling inflammatory response induced by bacteria in oysters.


Sujet(s)
Crassostrea , Régulation de l'expression des gènes , ARN messager , Vibrio , Animaux , Crassostrea/immunologie , Crassostrea/génétique , Vibrio/physiologie , Régulation de l'expression des gènes/immunologie , ARN messager/génétique , ARN messager/métabolisme , Immunité innée/génétique , Phosphoric monoester hydrolases/génétique , Phosphoric monoester hydrolases/métabolisme , Interleukine-17/génétique , Interleukine-17/immunologie , Interleukine-17/métabolisme , Phylogenèse , Séquence d'acides aminés , Analyse de profil d'expression de gènes/médecine vétérinaire , Alignement de séquences/médecine vétérinaire , Hémocytes/immunologie
9.
Science ; 384(6693): 301-306, 2024 Apr 19.
Article de Anglais | MEDLINE | ID: mdl-38635711

RÉSUMÉ

China's massive wave of urbanization may be threatened by land subsidence. Using a spaceborne synthetic aperture radar interferometry technique, we provided a systematic assessment of land subsidence in all of China's major cities from 2015 to 2022. Of the examined urban lands, 45% are subsiding faster than 3 millimeters per year, and 16% are subsiding faster than 10 millimeters per year, affecting 29 and 7% of the urban population, respectively. The subsidence appears to be associated with a range of factors such as groundwater withdrawal and the weight of buildings. By 2120, 22 to 26% of China's coastal lands will have a relative elevation lower than sea level, hosting 9 to 11% of the coastal population, because of the combined effect of city subsidence and sea-level rise. Our results underscore the necessity of enhancing protective measures to mitigate potential damages from subsidence.

10.
J Agric Food Chem ; 72(17): 9599-9610, 2024 May 01.
Article de Anglais | MEDLINE | ID: mdl-38646697

RÉSUMÉ

In the search for novel succinate dehydrogenase inhibitor (SDHI) fungicides to control Rhizoctonia solani, thirty-five novel pyrazole-4-carboxamides bearing either an oxime ether or an oxime ester group were designed and prepared based on the strategy of molecular hybridization, and their antifungal activities against five plant pathogenic fungi were also investigated. The results indicated that the majority of the compounds containing oxime ether demonstrated outstanding in vitro antifungal activity against R. solani, and some compounds also displayed pronounced antifungal activities against Sclerotinia sclerotiorum and Botrytis cinerea. Particularly, compound 5e exhibited the most promising antifungal activity against R. solani with an EC50 value of 0.039 µg/mL, which was about 20-fold better than that of boscalid (EC50 = 0.799 µg/mL) and 4-fold more potent than fluxapyroxad (EC50 = 0.131 µg/mL). Moreover, the results of the detached leaf assay showed that compound 5e could suppress the growth of R. solani in rice leaves with significant protective efficacies (86.8%) at 100 µg/mL, superior to boscalid (68.1%) and fluxapyroxad (80.6%), indicating promising application prospects. In addition, the succinate dehydrogenase (SDH) enzymatic inhibition assay revealed that compound 5e generated remarkable SDH inhibition (IC50 = 2.04 µM), which was obviously more potent than those of boscalid (IC50 = 7.92 µM) and fluxapyroxad (IC50 = 6.15 µM). Furthermore, SEM analysis showed that compound 5e caused a remarkable disruption to the characteristic structure and morphology of R. solani hyphae, resulting in significant damage. The molecular docking analysis demonstrated that compound 5e could fit into the identical binding pocket of SDH through hydrogen bond interactions as well as fluxapyroxad, indicating that they had a similar antifungal mechanism. The density functional theory and electrostatic potential calculations provided useful information regarding electron distribution and electron transfer, which contributed to understanding the structural features and antifungal mechanism of the lead compound. These findings suggested that compound 5e could be a promising candidate for SDHI fungicides to control R. solani, warranting further investigation.


Sujet(s)
Botrytis , Fongicides industriels , Oximes , Maladies des plantes , Pyrazoles , Rhizoctonia , Succinate Dehydrogenase , Rhizoctonia/effets des médicaments et des substances chimiques , Rhizoctonia/croissance et développement , Fongicides industriels/pharmacologie , Fongicides industriels/composition chimique , Succinate Dehydrogenase/antagonistes et inhibiteurs , Succinate Dehydrogenase/métabolisme , Pyrazoles/pharmacologie , Pyrazoles/composition chimique , Relation structure-activité , Maladies des plantes/microbiologie , Maladies des plantes/prévention et contrôle , Oximes/composition chimique , Oximes/pharmacologie , Botrytis/effets des médicaments et des substances chimiques , Botrytis/croissance et développement , Simulation de docking moléculaire , Protéines fongiques/composition chimique , Protéines fongiques/métabolisme , Protéines fongiques/génétique , Ascomycota/effets des médicaments et des substances chimiques , Ascomycota/composition chimique , Structure moléculaire , Antienzymes/pharmacologie , Antienzymes/composition chimique
11.
Front Oncol ; 14: 1372780, 2024.
Article de Anglais | MEDLINE | ID: mdl-38646428

RÉSUMÉ

Radiotherapy stands as a cornerstone in the treatment of numerous malignant tumors, including non-small cell lung cancer. However, the critical challenge of amplifying the tumoricidal effectiveness of radiotherapy while minimizing collateral damage to healthy tissues remains an area of significant research interest. Radiosensitizers, by methods such as amplifying DNA damage and fostering the creation of free radicals, play a pivotal role in enhancing the destructive impact of radiotherapy on tumors. Over recent decades, nano-dimensional radiosensitizers have emerged as a notable advancement. Their mechanisms include cell cycle arrest in the G2/M phase, combating tumor hypoxia, and others, thereby enhancing the efficacy of radiotherapy. This review delves into the evolving landscape of nanomaterials used for radiosensitization in non-small cell lung cancer. It provides insights into the current research progress and critically examines the challenges and future prospects within this burgeoning field.

12.
Nano Lett ; 24(7): 2308-2314, 2024 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-38324009

RÉSUMÉ

Two-dimensional (2D) nonlayered transition metal dichalcogenide (TMD) materials are emergent platforms for various applications from catalysis to quantum devices. However, their limited availability and nonstraightforward synthesis methods hinder our understanding of these materials. Here, we present a novel technique for synthesizing 2D nonlayered AuCrS2 via Au-assisted chemical vapor deposition (CVD). Our detailed structural analysis reveals the layer-by-layer growth of [AuCrS2] units atop an initial CrS2 monolayer, with Au binding to the adjacent monolayer of CrS2, which is in stark contrast with the well-known metal intercalation mechanism in the synthesis of many other 2D nonlayered materials. Theoretical calculations further back the crucial role of Cr in increasing the mobility of Au species and strengthening the adsorption energy of Au on CrS2, thereby aiding the growth throughout the CVD process. Additionally, the resulting free-standing nanoporous AuCrS2 (NP-AuCrS2) exhibits exceptional electrocatalytic properties for the hydrogen evolution reaction.

13.
J Pediatr Nurs ; 76: 140-149, 2024.
Article de Anglais | MEDLINE | ID: mdl-38402745

RÉSUMÉ

BACKGROUND: Returning to school can be challenging for children and adolescents with cancer who have been absent for a long time. As there is little known about the return to school experience of children and adolescents with cancer, this meta-synthesis aimed to describe the experiences of children and adolescent cancer patients as they return to school. METHODS: Seven English databases and three Chinese databases were searched from inception to March 14, 2023. The Joanna Briggs Institute Qualitative Assessment and Review Instrument (JBI-QARI) was used to appraise study quality. Data were synthesized using the Thomas and Harden thematic and content analysis method. RESULTS: Twelve qualitative studies met the inclusion criteria and were analyzed into meta-synthesis. Data synthesis led to constructing four analytical themes and twelve sub-themes. The four major themes constructed were:benefits to school re-entry, barriers to school re-entry, motivators to school re-entry and the adaptation process after returning to school. CONCLUSION: Children and adolescents with cancer were willing to return to education and can adapt to school life over time. But they were faced with challenges, including physical, psychological, and social barriers. Appropriate measures need to be taken to reduce those barriers. IMPLICATIONS TO PRACTICE: Findings can be used to inform future research and interventions to support a successful return to education for children and adolescents with cancer. Healthcare providers should address the needs of children and adolescents at different stages and actively work with schools, hospitals and families to help childhood cancer survivors successfully return to school.


Sujet(s)
Tumeurs , Recherche qualitative , Humains , Adolescent , Enfant , Tumeurs/psychologie , Adaptation psychologique , Femelle , Mâle , Établissements scolaires , Survivants du cancer/psychologie
14.
Sensors (Basel) ; 24(1)2024 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-38203120

RÉSUMÉ

Systematically and comprehensively enhancing road traffic safety using artificial intelligence (AI) is of paramount importance, and it is gradually becoming a crucial framework in smart cities. Within this context of heightened attention, we propose to utilize machine learning (ML) to optimize and ameliorate pedestrian crossing predictions in intelligent transportation systems, where the crossing process is vital to pedestrian crossing behavior. Compared with traditional analytical models, the application of OpenCV image recognition and machine learning methods can analyze the mechanisms of pedestrian crossing behaviors with greater accuracy, thereby more precisely judging and simulating pedestrian violations in crossing. Authentic pedestrian crossing behavior data were extracted from signalized intersection scenarios in Chinese cities, and several machine learning models, including decision trees, multilayer perceptrons, Bayesian algorithms, and support vector machines, were trained and tested. In comparing the various models, the results indicate that the support vector machine (SVM) model exhibited optimal accuracy in predicting pedestrian crossing probabilities and speeds, and it can be applied in pedestrian crossing prediction and traffic simulation systems in intelligent transportation.

15.
Glob Chang Biol ; 30(1): e17006, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37909670

RÉSUMÉ

Uncovering the mechanisms that lead to Amazon forest resilience variations is crucial to predict the impact of future climatic and anthropogenic disturbances. Here, we apply a previously used empirical resilience metrics, lag-1 month temporal autocorrelation (TAC), to vegetation optical depth data in C-band (a good proxy of the whole canopy water content) in order to explore how forest resilience variations are impacted by human disturbances and environmental drivers in the Brazilian Amazon. We found that human disturbances significantly increase the risk of critical transitions, and that the median TAC value is ~2.4 times higher in human-disturbed forests than that in intact forests, suggesting a much lower resilience in disturbed forests. Additionally, human-disturbed forests are less resilient to land surface heat stress and atmospheric water stress than intact forests. Among human-disturbed forests, forests with a more closed and thicker canopy structure, which is linked to a higher forest cover and a lower disturbance fraction, are comparably more resilient. These results further emphasize the urgent need to limit deforestation and degradation through policy intervention to maintain the resilience of the Amazon rainforests.


Sujet(s)
Forêt pluviale , Résilience psychologique , Effets anthropiques , Conservation des ressources naturelles/méthodes , Forêts
16.
J Magn Reson Imaging ; 59(1): 242-252, 2024 01.
Article de Anglais | MEDLINE | ID: mdl-37183807

RÉSUMÉ

BACKGROUND: Cognitive impairment frequently occurs in patients with brain metastases (BM) after whole-brain radiotherapy (WBRT). It is crucial to explore the underlying mechanisms of cognitive impairment in BM patients receiving WBRT. PURPOSE: To detect brain microstructural alterations in patients after WBRT by neurite orientation dispersion and density imaging (NODDI), and evaluate the performance of microstructural alterations in predicting cognitive impairment. STUDY TYPE: Prospective. POPULATION: Twenty-six patients (seven female; mean age, 60.9 years). FIELD STRENGTH/SEQUENCE: 3-T, multi-shell diffusion-weighted single-shot echo-planar sequence. Three-dimensional magnetization-prepared rapid acquisition with gradient echo sequence. ASSESSMENT: Mini-mental state examination (MMSE) evaluations were conducted prior to, following, 1 and 3 months after WBRT. The diffusion data were collected twice, 1 week before and 1 week after WBRT. NODDI analysis was conducted to assess microstructural alterations in whole brain (orientation dispersion index, neurite density index, volume fraction of isotropic water molecules). Reliable change indices (RCI) of MMSE were used to measure cognitive decline. The performance of support vector machine models based on NODDI parameters and clinical features (prednisone usage, tumor volume, etc.) in predicting MMSE-RCI was evaluated. STATISTICAL TESTS: Paired t-test to assess alterations of NODDI measures and MMSE during follow-up. Statistical significance level of P-value <0.05. RESULTS: Significantly decreased MMSE score was found at 3 months after WBRT. After WBRT, corpus callosum, medial prefrontal cortex, limbic lobe, occipital lobe, parietal lobe, putamen, globus pallidus lentiform, and thalamus demonstrated damage in NODDI parameters. The predicted MMSE-RCI based on NODDI features was significantly associated with the measured MMSE-RCI at 1 month (R = 0.573; P = 0.003) and 3 months (R = 0.687; P < 0.0001) after WBRT. DATA CONCLUSION: Microstructural alterations in several brain regions including the middle prefrontal and limbic cortexes were observed in patients with BM following WBRT, which may contribute to subsequent cognitive decline. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Sujet(s)
Tumeurs du cerveau , Dysfonctionnement cognitif , Humains , Femelle , Adulte d'âge moyen , Neurites/anatomopathologie , Tumeurs du cerveau/imagerie diagnostique , Tumeurs du cerveau/radiothérapie , Tumeurs du cerveau/anatomopathologie , Études prospectives , Irradiation crânienne , Encéphale/imagerie diagnostique , Encéphale/anatomopathologie , Imagerie par tenseur de diffusion/méthodes , Imagerie par résonance magnétique de diffusion/méthodes , Dysfonctionnement cognitif/imagerie diagnostique , Dysfonctionnement cognitif/étiologie , Dysfonctionnement cognitif/anatomopathologie
17.
Nanoscale ; 15(36): 14906-14911, 2023 Sep 21.
Article de Anglais | MEDLINE | ID: mdl-37654188

RÉSUMÉ

The interface engineering of two-dimensional transition metal dichalcogenides (2D-TMDs) and metals has been regarded as a promising strategy to modulate their outstanding electrical and optoelectronic properties. Chemical Vapour Deposition (CVD) is an effective strategy to regulate the contact interface between TMDs and metals via directly growing 2D TMDs on a 3D metal substrate. Nevertheless, the underlying mechanisms of interfacial phase formation and evolution during TMD growth on a metallic substrate are less known. In this work, we found a 2D non-van der Waals (vdW) Mo-rich phase (MoNSN+1) during thermal sulfidation of a Mo-Au surface alloy to molybdenum disulfide (MoS2) in a S-poor environment. Systematic atomic-scale observations reveal that the periodic Mo and S atomic layers are arranged separating from each other in the non-vdW Mo-rich phase, and the Mo-rich phase preferentially nucleates between outmost 2D MoS2 and a 3D nanostructured Au substrate which possesses copious surface steps and kinks. Theoretical calculations demonstrate that the appearance of the Mo-rich phase with a unique metallic nature causes an n-type contact interface with an ultralow transition energy barrier height. This study may help understand the formation mechanism of the interfacial second phase during the epitaxial growth of 2D-TMDs on 3D nanostructured metals, and provide a new approach to tune the Schottky barrier height by the design of the interfacial phase structure at the heterojunction.

18.
Light Sci Appl ; 12(1): 110, 2023 May 08.
Article de Anglais | MEDLINE | ID: mdl-37156789

RÉSUMÉ

Exceptional points pose exceptional difficulties to access and encircle. By simply gating graphene, it is now easier to hit the exceptional point.

19.
Adv Mater ; 35(6): e2207850, 2023 Feb.
Article de Anglais | MEDLINE | ID: mdl-36411956

RÉSUMÉ

Single-atom catalysts have attracted extensive attention due to their unique atomic structures and extraordinary activities in catalyzing chemical reactions. However, the lack of general and efficient approaches for producing high-density single atoms on suitably tailored supporting matrixes hinders their industrial applications. Here, a rapid melt-quenching strategy with high throughput to synthesize single atoms with high metal-atom loadings of up to 9.7 wt% or 2.6 at% on nanoporous metal compounds is reported, representing several-fold improvements compared to benchmarks in the literature. Mechanism characterizations reveal that the high-temperature melting provides the essential liquid environment and activation energy to achieve the atomization of metals, while the following rapid-quenching pins the isolated metal atoms and stabilizes the coordination environment. In comparison with carbon-supported single-atom catalysts, various collaboration combinations of single atoms and nanoporous metal compounds can be synthesized using the strategy, thus achieving efficient hydrazine oxidation-assisted H2 production. This synthesis protocol is highly compatible with automatic operation, which provides a feasible and general route to design and manufacture specific single-atom catalysts with tunable atomic metal components and supporting matrixes, thus promoting the deployment of single-atom catalysts for various energy technology applications.

20.
Front Psychiatry ; 13: 924277, 2022.
Article de Anglais | MEDLINE | ID: mdl-36213910

RÉSUMÉ

Poststroke depression significantly affects health and quality of life of stroke patients. This study evaluates the role of social support in influencing poststroke depression. The literature search was conducted in electronic databases and study selection was based on precise eligibility criteria. The prevalence rates reported by individual studies were pooled. A meta-analysis of standardized mean differences (SMD) in social support between depressed and non-depressed stroke patients was performed. The odds ratios and correlation coefficients showing the relationship between social support and depression were pooled to achieve overall estimates. Twenty-five studies (9431 patients) were included. The prevalence of depression was 36% [95% confidence interval (CI): 28, 45]. Patients with poststroke depression had significantly lower social support in comparison with patients with no or lower levels of depression [SMD in social support scores -0.338 (95% CI: -0.589, -0.087); p = 0.008]. The odds of depression were lower in patients receiving higher levels of social support [OR 0.82 (95% CI: 0.69, 0.95)] but were higher in patients who were receiving weaker social support [OR 5.22 (95% CI: -0.87, 11.31)]. A meta-analysis of correlation coefficients found a significantly inverse correlation between social support and poststroke depression [r -0.336 (95% CI: -0.414, -0.254)]. Poststroke depression has a significant independent inverse association with social support.

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