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1.
Biomed Pharmacother ; 179: 117292, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151314

RESUMO

A type of colorectal cancer (CRC),Colitis-associated colorectal cancer (CAC), is closely associated with chronic inflammation and gut microbiota dysbiosis. Berberine (BBR) has a long history in the treatment of intestinal diseases, which has been reported to inhibit colitis and CRC. However, the mechanism of its action is still unclear. Here, this study aimed to explore the potential protective effects of BBR on azoxymethane (AOM)/dextransulfate sodium (DSS)-induced colitis and tumor mice, and to elucidate its potential molecular mechanisms by microbiota, genes and metabolic alterations. The results showed that BBR inhibited the gut inflammation and improved the function of mucosal barrier to ameliorate AOM/DSS-induced colitis. And BBR treatment significantly reduced intestinal tumor development and ki-67 expression of intestinal tissue along with promoted apoptosis. Through microbiota analysis based on the 16 S rRNA gene, we found that BBR treatment improved intestinal microbiota imbalance in AOM/DSS-induced colitis and tumor mice, which were characterized by an increase of beneficial bacteria, for instance Akkermanisa, Lactobacillus, Bacteroides uniformis and Bacteroides acidifaciens. In addition, transcriptome analysis showed that BBR regulated colonic epithelial signaling pathway in CAC mice particularly by tryptophan metabolism and Wnt signaling pathway. Notably, BBR treatment resulted in the enrichment of amino acids metabolism and microbiota-derived SCFA metabolites. In summary, our research findings suggest that the gut microbiota-amino acid metabolism-Wnt signaling pathway axis plays critical role in maintaining intestinal homeostasis, which may provide new insights into the inhibitory effects of BBR on colitis and colon cancer.

2.
J Colloid Interface Sci ; 676: 1011-1022, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39068833

RESUMO

Polyimide (PI) aerogels have various applications in aerospace, national defense, military industry, and rail transit equipment. This paper reports a series of ultra-lightweight, high elasticity, high strength, low thermal conductivity, and high flame retardant rGO/PI nanocomposite aerogels prepared by the ice templating method. The effects of freezing processes (unidirectional freezing and random freezing), chemical composition, and environmental temperature (-196-200 °C) on the morphology, mechanical, and thermal properties of the aerogels were systematically studied. The results indicated that unidirectional aerogels exhibit anisotropic mechanical properties and thermal performance. Compression in the horizontal direction showed high elasticity, high fatigue resistance, and superior thermal insulation. Meanwhile, in the vertical direction, it demonstrated high strength (PI-G-9 reaching 14 MPa). After 10,000 cycles of compression in the horizontal direction (at 50 % strain), the unidirectional PI-G-5 aerogel still retains 90.32 % height retention, and 78.5 % stress retention, and exhibited a low stable energy loss coefficient (22.11 %). It also possessed a low thermal conductivity (32.8 mW m-1 K-1) and demonstrated good thermal insulation performance by sustaining at 200 °C for 30 min. Interestingly, the elasticity of the aerogels was enhanced with decreasing temperatures, achieving a height recovery rate of up to 100 % when compressed in liquid nitrogen. More importantly, the rGO/PI aerogels could be utilized over a wide temperature range (-196-200 °C) and had a high limiting oxygen index (LOI) ranging from 43.3 to 48.1 %. Therefore, this work may provide a viable approach for designing thermal insulation and flame-retardant protective materials with excellent mechanical properties that are suitable for harsh environments.

3.
Front Oncol ; 14: 1397505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952558

RESUMO

Primary hepatocellular carcinoma (PHC) is associated with high rates of morbidity and malignancy in China and throughout the world. In clinical practice, a combination of ultrasound and alpha-fetoprotein (AFP) measurement is frequently employed for initial screening. However, the accuracy of this approach often falls short of the desired standard. Consequently, this study aimed to investigate the enhancement of precision of preliminary detection of PHC by ensemble learning techniques. To achieve this, 712 patients with PHC and 1887 healthy controls were enrolled for the assessment of four ensemble learning methods, namely, Random Forest (RF), LightGBM, Xgboost, and Catboost. A total of eleven characteristics, comprising nine serological indices and two demographic indices, were selected from the participants for use in detecting PHC. The findings identified an optimal feature subset consisting of eight features, namely AFP, albumin (ALB), alanine aminotransferase (ALT), platelets (PLT), age, alkaline phosphatase (ALP), hemoglobin (Hb), and body mass index (BMI), that achieved the highest classification accuracy of 96.62%. This emphasizes the importance of the collective use of these features in PHC diagnosis. In conclusion, the results provide evidence that the integration of serological and demographic indices together with ensemble learning models, can contribute to the precision of preliminary diagnosis of PHC.

4.
Neuroscience ; 554: 83-95, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38944149

RESUMO

Neonatal hypoxic-ischemic brain damage (HIBD) can lead to mortality and severe neurological dysfunction. Emodin is a natural anthraquinone derivative that is easy to obtain and has good neuroprotective effects. This study aimed to investigate the neuroprotective effect of emodin on neonatal mouse HIBD. The modified Rice-Vannucci method was used to induce HIBD in mouse pups. Eighty postnatal 7-day (P7) C57BL/6 neonatal mice were randomly divided into the sham group (sham), vehicle group (vehicle), and emodin group (emodin). TTC staining and whole-brain morphology were used to evaluate the infarct volume and morphology of the brain tissue. The condition of the neurons was observed through Nissl staining, HE staining, FJC staining, immunofluorescence and Western blot for NeuN, IBA-1, and GFAP. The physiological status of the mice was evaluated using weight measurements. The neural function of the mice was assessed using the negative geotaxis test, righting reflex test, and grip test. TUNEL staining was used to detect apoptosis in brain cells. Finally, Western blot and immunofluorescence were used to detect the expression levels of apoptosis-related proteins, such as P53, cleaved caspase-3, Bax and Bcl-2, in the brain. Experiments have shown that emodin can reduce the cerebral infarct volume, brain oedema, neuronal apoptosis, and degeneration and improve the reconstruction of brain tissue morphology, neuronal morphology, physiological conditions, and neural function. Additionally, emodin inhibited the expression of proapoptotic proteins such as P53, Bax and cleaved caspase-3 and promoted the expression of the antiapoptotic protein Bcl-2. Emodin attenuates HIBD by inhibiting neuronal apoptosis in neonatal mice.


Assuntos
Animais Recém-Nascidos , Apoptose , Encéfalo , Emodina , Hipóxia-Isquemia Encefálica , Camundongos Endogâmicos C57BL , Neurônios , Fármacos Neuroprotetores , Animais , Emodina/farmacologia , Apoptose/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/patologia , Hipóxia-Isquemia Encefálica/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/metabolismo , Camundongos , Modelos Animais de Doenças
5.
Theranostics ; 14(8): 3358-3384, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855176

RESUMO

With the increase in the aging population, the occurrence of neurological disorders is rising. Recently, stem cell therapy has garnered attention due to its convenient sourcing, minimal invasiveness, and capacity for directed differentiation. However, there are some disadvantages, such as poor quality control, safety assessments, and ethical and logistical issues. Consequently, scientists have started to shift their attention from stem cells to extracellular vesicles due to their similar structures and properties. Beyond these parallels, extracellular vesicles can enhance biocompatibility, facilitate easy traversal of barriers, and minimize side effects. Furthermore, stem cell-derived extracellular vesicles can be engineered to load drugs and modify surfaces to enhance treatment outcomes. In this review, we summarize the functions of native stem cell-derived extracellular vesicles, subsequently review the strategies for the engineering of stem cell-derived extracellular vesicles and their applications in Alzheimer's disease, Parkinson's disease, and stroke, and discuss the challenges and solutions associated with the clinical translation of stem cell-derived extracellular vesicles.


Assuntos
Doença de Alzheimer , Vesículas Extracelulares , Doença de Parkinson , Células-Tronco , Acidente Vascular Cerebral , Humanos , Vesículas Extracelulares/transplante , Vesículas Extracelulares/metabolismo , Doença de Parkinson/terapia , Doença de Parkinson/metabolismo , Doença de Alzheimer/terapia , Doença de Alzheimer/metabolismo , Animais , Acidente Vascular Cerebral/terapia , Transplante de Células-Tronco/métodos
6.
J Contam Hydrol ; 264: 104347, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657473

RESUMO

Mercury contamination in groundwater is a serious global environmental issue that poses threats to human and environmental health. While MoS2 nanosheets have been proven promising in removing Hg from groundwater, an effective tool for in situ groundwater remediation is still needed. In this study, we investigated the transport and retention behavior of MoS2 nanosheets in sand column, and employed the formed MoS2in situ reactive zone (IRZ) for the remediation of Hg-contaminated groundwater. Breakthrough test revealed that high flow velocity and MoS2 initial concentration promoted the transport of MoS2 in sand column, while the addition of Ca ions increased the retention of MoS2. In Hg removal experiments, the groundwater flow velocity did not influence the Hg removal capacity due to the fast reaction rate between MoS2 and Hg. With an optimized MoS2 loading, MoS2IRZ effectively reduced the Hg effluent concentration down to <1 µg/L without apparent Hg remobilization. Additionally, flake-like MoS2 employed in this study showed much better Hg removal performance than flower-like and bulk MoS2, as well as other reported materials, with the Hg removal capacity a few to tens of times higher than those materials. These results suggest that MoS2 nanosheets have the potential to be an efficient IRZ reactive material for in situ remediation of Hg in contaminated groundwater.


Assuntos
Dissulfetos , Recuperação e Remediação Ambiental , Água Subterrânea , Mercúrio , Molibdênio , Poluentes Químicos da Água , Água Subterrânea/química , Mercúrio/química , Poluentes Químicos da Água/química , Recuperação e Remediação Ambiental/métodos , Molibdênio/química , Dissulfetos/química , Nanoestruturas/química
7.
J Hazard Mater ; 471: 134292, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38631254

RESUMO

The critical challenge of effectively removing Pb-EDTA complexes and Pb(II) ions from wastewater is pivotal for environmental remediation. This research introduces a cutting-edge bulk-MoS2/H2O2 system designed for the simultaneous decomplexation of Pb-EDTA complexes and extraction of free Pb(II) ions, streamlining the process by eliminating the need for subsequent treatment stages. The system exhibits outstanding efficiency, achieving 98.1% decomplexation of Pb-EDTA and 98.6% removal of Pb. Its effectiveness is primarily due to the generation of reactive oxygen species, notably •OH and O2•- radicals, facilitated by bulk-MoS2 and H2O2. Key operational parameters such as reagent dosages, Pb(II): EDTA molar ratios, solution pH, and the presence of coexisting ions were meticulously evaluated to determine their impact on the system's performance. Through a suite of analytical techniques, the study confirmed the disruption of Pb-O and Pb-N bonds, further elucidating the decomplexation process. It also underscored the synergistic role of bulk-MoS2's adsorption properties and the formation of PbMoO4-like precipitates in enhancing Pb elimination. Demonstrating the bulk-MoS2/H2O2 system as a robust, one-step solution that meets stringent Pb emission standards, this study provides in-depth insights into the removal mechanisms of Pb-EDTA, affirming its potential for broader application in wastewater treatment practices.

8.
Eur J Pharmacol ; 969: 176429, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38423241

RESUMO

Cancer cachexia, a multi-organ disorder resulting from tumor and immune system interactions, prominently features muscle wasting and affects the survival of patients with cancer. Ursolic acid (UA) is known for its antioxidant, anti-inflammatory, and anticancer properties. However, its impact on cancer cachexia remains unexplored. This study aimed to assess the efficacy of UA in addressing muscle atrophy and organ dysfunction in cancer cachexia and reveal the mechanisms involved. UA dose-dependently ameliorated C2C12 myotube atrophy. Mechanistically, it inhibited the expression of muscle-specific RING finger containing protein 1 (MURF1) and the phosphorylation of signal transducer and activator of transcription 3 (STAT3), and upregulated the mRNA or protein levels of myogenic differentiation antigen and myogenin in cultured C2C12 myotubes treated with conditioned medium. In vivo, UA protected CT26 tumor-bearing mice against loss of body weight, as well as increased skeletal muscle and epididymal fat without affecting tumor growth. Additionally, UA increased food intake in CT26 tumor-bearing mice. The mRNA expression of tumor necrosis-α and interleukin 6 was significantly downregulated in the intestine, gastrocnemius, and heart tissues following 38 d UA administration. UA treatment reversed the levels of myocardial function indicators, including creatine kinase, creatine kinase-MB, lactate dehydrogenase, car-dial troponin T, and glutathione. Finally, UA treatment significantly inhibited the expression of MURF1, the phosphorylation of nuclear factor kappa-B p65, and STAT3 in the gastrocnemius muscle and heart tissues of cachexic mice. Our findings suggest that UA is a promising natural compound for developing dietary supplements for cancer cachexia therapy owing to its anti-catabolic effects.


Assuntos
Caquexia , Neoplasias , Humanos , Animais , Camundongos , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/metabolismo , Ácido Ursólico , Fator de Transcrição STAT3/metabolismo , Neoplasias/patologia , Fibras Musculares Esqueléticas , Músculo Esquelético/metabolismo , Transdução de Sinais , Atrofia Muscular/metabolismo , RNA Mensageiro/metabolismo
10.
Nanoscale ; 15(43): 17434-17442, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37855687

RESUMO

Epsilon-near-zero (ENZ) materials with vanishing permittivity exhibit unprecedented optical nonlinearity within subwavelength propagation lengths in the ENZ region, making them promising photoelectric materials that have achieved exciting results in ultrafast pulse laser modulations. In this study, we fabricated a novel saturable absorber (SA) based on a corrugated indium tin oxide (CITO) film with a symmetrical geometry using a low-cost self-assembly process. The strong saturable absorption of the CITO film triggered by the ENZ effect at normal incidence was comparable to that of the planar indium tin oxide (ITO) film at an optimal 60° incidence (TM polarization) at 1340 nm. In addition, the strong nonlinear optical properties of the CITO film were not limited by the incident angle and polarization state of the pump laser over a wide range of 0-20°. Benefiting from the excellent saturable absorption of CITO-based SA at normal incidence, a Q-switching operation with CITO-based SA at 1.34 µm was achieved in a Nd:YVO4 solid-state laser system, obtaining pulses of a duration of 85.6 ns, which was one order of magnitude narrower than that of the planar ITO-based SA. This study presents a new strategy for developing high-performance ENZ-based SAs and ultrafast lasers.

11.
BMC Anesthesiol ; 23(1): 168, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198555

RESUMO

OBJECTIVES: The use of intravenous analgesics during emergency cesarean section may lead to adverse neonatal outcomes. In our study, we investigated whether a single intravenous (i.v.) dose of 25 mg esketamine administered to parturients with inadequate analgesia during epidural anesthesia for cesarean section would affect the neonate. DESIGN: We reviewed the records of parturients who were transferred from labor analgesia to epidural anesthesia for emergency cesarean section from January 2021 to April 2022. Parturients were grouped by whether they received esketamine infusions during the incision-delivery interval. Neonatal outcomes, including umbilical arterial-blood gas analysis (UABGA), Apgar score, and total days spent by the neonate in the hospital, were compared between the two groups. The secondary outcomes of this study included BP, heart rate (HR), SPO2 and the incidence of adverse effects in parturients during operation. SETTING: China. RESULTS: After propensity score matching, 31 patients remained in each of the non-esketamine and esketamine groups. There were no significant differences in neonatal outcomes, including UABGA, Apgar score, and total days in the hospital, between the two groups. Additionally, our study showed a similar hemodynamic performance in parturients between the two groups during operation. CONCLUSIONS: Intravenous esketamine (25 mg) is safe for neonates when it is given to parturients transferred from labor analgesia to emergency cesarean section.


Assuntos
Analgesia Epidural , Analgesia Obstétrica , Anestesia Epidural , Recém-Nascido , Gravidez , Humanos , Feminino , Cesárea , Estudos Retrospectivos , Analgesia Epidural/efeitos adversos , Analgésicos , Analgesia Obstétrica/efeitos adversos
12.
J Genet Genomics ; 50(7): 462-472, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37068629

RESUMO

Since the discovery of the first transposon by Dr. Barbara McClintock, the prevalence and diversity of transposable elements (TEs) have been gradually recognized. As fundamental genetic components, TEs drive organismal evolution not only by contributing functional sequences (e.g., regulatory elements or "controllers" as phrased by Dr. McClintock) but also by shuffling genomic sequences. In the latter respect, TE-mediated gene duplications have contributed to the origination of new genes and attracted extensive interest. In response to the development of this field, we herein attempt to provide an overview of TE-mediated duplication by focusing on common rules emerging across duplications generated by different TE types. Specifically, despite the huge divergence of transposition machinery across TEs, we identify three common features of various TE-mediated duplication mechanisms, including end bypass, template switching, and recurrent transposition. These three features lead to one common functional outcome, namely, TE-mediated duplicates tend to be subjected to exon shuffling and neofunctionalization. Therefore, the intrinsic properties of the mutational mechanism constrain the evolutionary trajectories of these duplicates. We finally discuss the future of this field including an in-depth characterization of both the duplication mechanisms and functions of TE-mediated duplicates.


Assuntos
Elementos de DNA Transponíveis , Genômica , Elementos de DNA Transponíveis/genética , Mutação , Sequências Reguladoras de Ácido Nucleico , Evolução Molecular
13.
Molecules ; 28(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36903276

RESUMO

Two novel electrochromic aromatic polyimides (named as TPA-BIA-PI and TPA-BIB-PI, respectively) with pendent benzimidazole group were synthesized from 1,2-Diphenyl-N,N'-di-4-aminophenyl-5-amino-benzimidazole and 4-Amino-4'-aminophenyl-4″-1-phenyl-benzimidazolyl-phenyl-aniline with 4,4'-(hexafluoroisopropane) phthalic anhydride (6FDA) via two-step polymerization process, respectively. Then, polyimide films were prepared on ITO-conductive glass by electrostatic spraying, and their electrochromic properties were studied. The results showed that due to the π-π* transitions, the maximum UV-Vis absorption bands of TPA-BIA-PI and TPA-BIB-PI films were located at about 314 nm and 346 nm, respectively. A pair of reversible redox peaks of TPA-BIA-PI and TPA-BIB-PI films that were associated with noticeable color changed from original yellow to dark blue and green were observed in the cyclic voltammetry (CV) test. With increasing voltage, new absorption peaks of TPA-BIA-PI and TPA-BIB-PI films emerged at 755 nm and 762 nm, respectively. The switching/bleaching times of TPA-BIA-PI and TPA-BIB-PI films were 13 s/16 s and 13.9 s/9.5 s, respectively, showing that these polyimides can be used as novel electrochromic materials.

14.
Opt Express ; 31(2): 2208-2224, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785239

RESUMO

Ultrathin planar transparent conducting oxide (TCO) films are commonly used to enhance the optical response of epsilon-near-zero (ENZ) devices; however, our results suggest that thickness-dependent loss renders them ineffective. Here, we investigated the thickness-dependent loss of indium tin oxide (ITO) films and their effect on the ENZ-enhanced optical responses of ITO and ITO/SiO2 multilayer stacks. The experimental and computational results show that the optical loss of ITO films increases from 0.47 to 0.70 as the thickness decreases from 235 to 52 nm, which results in a reduction of 60% and 45% in the maximum field enhancement factor of a 52-nm monolayer ITO and 4-layer ITO/SiO2 multilayer stack, respectively. The experimental results show that the ENZ-enhanced nonlinear absorption coefficient of the 52-nm single-layer ITO film is -1.6 × 103 cm GW-1, which is 81% lower than that of the 235-nm ITO film (-8.6 × 103 cm GW-1), indicating that the thickness-dependent loss makes the ultrathin TCO films unable to obtain greater nonlinear responses. In addition, the increased loss reduces the cascading Berreman transmission valley intensity of the 4-layer ITO/SiO2 multilayer stack, resulting in a 42% reduction in the ENZ-enhanced nonlinear absorption coefficient compared to the 235-nm ITO film and a faster hot electron relaxation time. Our results suggest that the thickness and loss trade-off is an intrinsic property of TCO films and that the low-loss ultrathin TCO films are the key to the robust design and fabrication of novel ENZ devices based on flat ultrathin TCO films.

15.
Front Psychiatry ; 14: 1318637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38283894

RESUMO

Introduction: Autism spectrum disorder (ASD) is a multifaceted developmental condition that commonly appears during early childhood. The etiology of ASD remains multifactorial and not yet fully understood. The identification of biomarkers may provide insights into the underlying mechanisms and pathophysiology of the disorder. The present study aimed to explore the causes of ASD by investigating the key biomedical markers, trace elements, and microbiota factors between children with autism spectrum disorder (ASD) and control subjects. Methods: Medline, PubMed, ProQuest, EMBASE, Cochrane Library, PsycINFO, Web of Science, and EMBSCO databases have been searched for publications from 2012 to 2023 with no language restrictions using the population, intervention, control, and outcome (PICO) approach. Keywords including "autism spectrum disorder," "oxytocin," "GABA," "Serotonin," "CRP," "IL-6," "Fe," "Zn," "Cu," and "gut microbiota" were used for the search. The Joanna Briggs Institute (JBI) critical appraisal checklist was used to assess the article quality, and a random model was used to assess the mean difference and standardized difference between ASD and the control group in all biomedical markers, trace elements, and microbiota factors. Results: From 76,217 records, 43 studies met the inclusion and exclusion criteria and were included in this meta-analysis. The pooled analyses showed that children with ASD had significantly lower levels of oxytocin (mean differences, MD = -45.691, 95% confidence interval, CI: -61.667, -29.717), iron (MD = -3.203, 95% CI: -4.891, -1.514), and zinc (MD = -6.707, 95% CI: -12.691, -0.722), lower relative abundance of Bifidobacterium (MD = -1.321, 95% CI: -2.403, -0.238) and Parabacteroides (MD = -0.081, 95% CI: -0.148, -0.013), higher levels of c-reactive protein, CRP (MD = 0.401, 95% CI: 0.036, 0.772), and GABA (MD = 0.115, 95% CI: 0.045, 0.186), and higher relative abundance of Bacteroides (MD = 1.386, 95% CI: 0.717, 2.055) and Clostridium (MD = 0.281, 95% CI: 0.035, 0.526) when compared with controls. The results of the overall analyses were stable after performing the sensitivity analyses. Additionally, no substantial publication bias was observed among the studies. Interpretation: Children with ASD have significantly higher levels of CRP and GABA, lower levels of oxytocin, iron, and zinc, lower relative abundance of Bifidobacterium and Parabacteroides, and higher relative abundance of Faecalibacterium, Bacteroides, and Clostridium when compared with controls. These results suggest that these indicators may be a potential biomarker panel for the diagnosis or determining therapeutic targets of ASD. Furthermore, large, sample-based, and randomized controlled trials are needed to confirm these results.

16.
Phys Chem Chem Phys ; 25(1): 796-805, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36510741

RESUMO

Coexistence of intrinsic ferromagnetism and piezoelectricity, namely piezoelectric ferromagnetism (PFM), is crucial to advance multifunctional spintronic technologies. In this work, we demonstrate that Janus monolayer YBrI is a PFM, which is dynamically, mechanically and thermally stable. The electronic correlation effects on the physical properties of YBrI are investigated by using generalized gradient approximation plus U (GGA+U) approach. For out-of-plane magnetic anisotropy, YBrI is a ferrovalley (FV) material, and its valley splitting is larger than 82 meV within the considered U range. The anomalous valley Hall effect (AVHE) can be achieved under an in-plane electric field. However, for in-plane magnetic anisotropy, YBrI is a common ferromagnetic (FM) semiconductor. When considering intrinsic magnetic anisotropy, the easy axis of YBrI is always in-plane, and its magnetic anisotropy energy (MAE) varies from 0.309 meV to 0.237 meV (U = 0.0 eV to 3.0 eV). However, the magnetization can be adjusted from the in-plane to out-of-plane direction by an external magnetic field, and then lead to the occurrence of valley polarization. Moreover, the missing centrosymmetry along with broken mirror symmetry results in both in-plane and out-of-plane piezoelectricity in the YBrI monolayer. At a typical U = 2.0 eV, the piezoelectric strain coefficient d11 is predicted to be -5.61 pm V-1, which is higher than or comparable with the ones of other known two-dimensional (2D) materials. The electronic and piezoelectric properties of YBrI can be effectively tuned by applying biaxial strain. For example, tensile strain can enhance valley splitting and d11 (absolute value). The predicted magnetic transition temperature of YBrI is higher than those of experimentally synthesized 2D FM materials CrI3 and Cr2Ge2Te6. Our findings of these distinctive properties could pave the way for designing multifunctional spintronic devices, and bring forward a new perspective for constructing 2D materials.

17.
Oxid Med Cell Longev ; 2022: 1330928, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36425058

RESUMO

Objective: Our previous results showed that icariin (ICA) could inhibit apoptosis and provide neuroprotection against hypoxic-ischemic brain damage (HIBD) in neonatal mice, but the specific mechanism of its neuroprotective effect remains unknown. This study aims at exploring whether ICA plays a neuroprotective role in apoptosis inhibition by regulating autophagy through the estrogen receptor α (ERα)/estrogen receptor ß (ERß) pathway in neonatal mice with HIBD. Methods: A neonatal mouse model of HIBD was constructed in vivo, and an oxygen and glucose deprivation (OGD) model in HT22 cells from the hippocampal neuronal system was constructed in vitro. The effects of ICA pretreatment on autophagy and the expression of ERα and ERß were detected in vitro and in vivo, respectively. ICA pretreatment was also supplemented with the autophagy inhibitor 3-methyladenine (3-MA), ERα inhibitor methylpiperidino pyrazole (MPP), and ERß inhibitor 4-(2-phenyl-5,7-bis (trifluoromethyl) pyrazolo [1,5-a] pyramidin-3-yl) phenol (PHTPP) to further detect whether ICA pretreatment can activate the ERα/ERß pathway to promote autophagy and reduce HIBD-induced apoptosis to play a neuroprotective role against HIBD in neonatal mice. Results: ICA pretreatment significantly promoted autophagy in HIBD mice. Treatment with 3-MA significantly inhibited the increase in autophagy induced by ICA pretreatment, reversed the neuroprotective effect of ICA pretreatment, and promoted apoptosis. Moreover, ICA pretreatment significantly increased the expression levels of the ERα and ERß proteins in HIBD newborn mice. Both MPP and PHTPP administration significantly inhibited the expression levels of the ERα and ERß proteins activated by ICA pretreatment, reversed the neuroprotective effects of ICA pretreatment, inhibited the increase in autophagy induced by ICA pretreatment, and promoted apoptosis. Conclusion: ICA pretreatment may promote autophagy by activating the ERα and ERß pathways, thus reducing the apoptosis induced by HIBD and exerting a neuroprotective effect on neonatal mice with HIBD.


Assuntos
Hipóxia-Isquemia Encefálica , Fármacos Neuroprotetores , Animais , Camundongos , Animais Recém-Nascidos , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Hipocampo/metabolismo
18.
ACS Nano ; 16(8): 12878-12888, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35905035

RESUMO

Ultrafast all-optical switches based on epsilon-near-zero (ENZ)-enhanced nonlinear refraction in transparent conducting oxides have achieved exciting results in realizing large absolute modulations. However, broad-band, polarization-independent, and wide-angle ultrafast all-optical switches have been challenging to produce, due to the inherent narrow band, polarization-dependent, and angle-dependent characteristics of the ENZ effect. To this end, we propose an ultrafast all-optical switch based on the enhanced nonlinear absorption of corrugated indium tin oxide (ITO) thin films. Taking advantage of the perfect absorption and localized field enhancement of the ENZ and localized surface plasmon resonance modes, we significantly enhanced the nonlinear absorption of the corrugated ITO film in the 1450-1650 nm telecom band. The experimental results show that the nonlinear saturable absorption coefficient of the corrugated ITO film at 1450 nm was as high as -1.5 × 105 cm GW-1, enabling all-optical switching to obtain an extinction ratio of 14.32 dB and an ultrafast switching time of 350 fs at a pump fluence of 18.51 mJ cm-2. Furthermore, the all-optical switch achieved an extinction ratio of over 15 dB and an insertion loss of approximately 2.6 dB within the 200 nm absorption band and exhibited polarization-independent and wide-angle features. The ultrafast temporal response can be attributed to intraband transient bleaching of the corrugated ITO film. Our findings demonstrate that corrugated ENZ films can overcome the inherent narrow-band, polarization-dependent, and angle-dependent problems of natural ENZ materials without increasing the response time, making them a potential ENZ ultrafast all-optical switching material platform.

19.
Gen Psychiatr ; 35(1): e100685, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309241

RESUMO

Background: Schizophrenia is a serious mental illness affecting approximately 20 million individuals globally. Both genetic and environmental factors contribute to the illness. If left undiagnosed and untreated, schizophrenia results in impaired social function, repeated hospital admissions, reduced quality of life and decreased life expectancy. Clinical diagnosis largely relies on subjective evidence, including self-reported experiences, and reported behavioural abnormalities followed by psychiatric evaluation. In addition, psychoses may occur along with other conditions, and the symptoms are often episodic and transient, posing a significant challenge to the precision of diagnosis. Therefore, objective, specific tests using biomarkers are urgently needed for differential diagnosis of schizophrenia in clinical practice. Aims: We aimed to provide evidence-based and consensus-based recommendations, with a summary of laboratory measurements that could potentially be used as biomarkers for schizophrenia, and to discuss directions for future research. Methods: We searched publications within the last 10 years with the following keywords: 'schizophrenia', 'gene', 'inflammation', 'neurotransmitter', 'protein marker', 'gut microbiota', 'pharmacogenomics' and 'biomarker'. A draft of the consensus was discussed and agreed on by all authors at a round table session. Results: We summarised the characteristics of candidate diagnostic markers for schizophrenia, including genetic, inflammatory, neurotransmitter, peripheral protein, pharmacogenomic and gut microbiota markers. We also proposed a novel laboratory process for diagnosing schizophrenia in clinical practice based on the evidence summarised in this paper. Conclusions: Further efforts are needed to identify schizophrenia-specific genetic and epigenetic markers for precise diagnosis, differential diagnosis and ethnicity-specific markers for the Chinese population. The development of novel laboratory techniques is making it possible to use these biomarkers clinically to diagnose disease.

20.
ACS Omega ; 7(11): 9267-9275, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350369

RESUMO

Two-dimensional materials with excellent surface-volume ratios and massive reaction sites recently have been receiving attention for gas sensing. With first-principles calculations, we explored the performance of monolayer Sc2CF2 as a gas sensor. We investigated how molecule adsorption affects its electronic structure and optical properties. It is found that a large charge transfer quantity happens between Sc2CF2 and NO2, which results from the fact that the lowest unoccupied molecular orbital (LUMO) of NO2 is below the valence band maximum (VBM) of Sc2CF2. Moreover, the MD simulation shows that NO2 can adsorb on the Sc2CF2 surface stably at room temperature. We explored the effect of biaxial strain on the adsorption energy and charge transfer quantity of each system, and the results show that the biaxial strain can enhance both the adsorption energy and charge transfer quantity of the NO2 system and thus can improve the sensitivity of Sc2CF2 in detecting the NO2 molecule. Furthermore, we investigated the adsorption behavior and charge transfer of polar polyatomic molecules at the Sc2CF2 surface with h-BN as a substrate, and the results demonstrate that the h-BN substrate can hardly modify the main results. Our result predicts that Sc2CF2 can be a promising selective and sensitive sensor to detect the NO2 molecule, and could also give a theoretical guide for other terminated MXenes used for gas sensors or detectors.

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