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1.
Nano Lett ; 24(39): 12271-12276, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39297547

RESUMO

Modern quantum device fabrication often requires precisely adding and removing materials in situ at nanoscales, which is challenging for high-quality correlated oxide devices. In this work, we present a novel nanofabrication method that remotely controls the interfacial metal-insulator transition at the LaAlO3/SrTiO3 interface by selectively removing an LaAlO3 overlayer using a diamond tip. Remarkably, we observe a large force window within which single atomic layer precision of control is achievable. Our results confirm the critical thickness and charge transfer mechanism through a layer-by-layer removal process at the interface. Additionally, high-quality nanodevices, including nanochannels and single electron transistors, are successfully fabricated using this method. This nonvolatile and high-precision nanofabrication method provides a promising oxide platform for quantum engineering by harnessing the rich electron correlations at the nanoscale.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38976051

RESUMO

This study delves into the correlation between the cumulative burden of mental disorders and self-harm, shame, and insight in young female patients with schizophrenia. A prospective randomized controlled study was used to recruit 62 female schizophrenia patients who met the recruitment conditions from January 2022 to December 2023. The participants were randomly divided into an experimental group (31 cases) and a control group (31 cases) using a computer-based random number distribution method. The experimental group underwent an 8-week Mindfulness-Based Cognitive Therapy (MBCT) intervention, while the control group received conventional treatment. Data was collected using the Modified EI-SHS scale, the Link's Stigma Scale (LSS), the Five-factor Mindfulness Scale (FFMQ), and the Self-awareness and Therapeutic Attitude Questionnaire (ITAQ) before and after the intervention. One-way ANOVA and repeated measure ANOVA were used to compare and analyze the two groups of data. The experimental group exhibited a significant reduction in EI-SHS and LSS scores (100.26 ± 11.48 vs. 88.35 ± 10.09, 112.81 ± 12.30 vs. 100.50 ± 13.52, p < 0.01), coupled with significant increase in FFMQ and ITAQ scores (113.77 ± 12.25 vs. 128.31 ± 14.09, 14.03 ± 4.18 vs. 17.30 ± 2.96, p < 0.01). A positive correlation was found between overall stigma scores and mood disorder scores (r = 0.379, P < 0.011). Correlation analysis revealed a negative correlation between mindfulness (self-awareness) and stigma (r = -0.128, P = 0.025). MBCT effectively reduced stigma in young women with schizophrenia and improved coping tendencies, cognitive status, and attitudes toward mental illness, ultimately reducing the cumulative burden of mental disorders and self-harm in these patients. Increased levels of mindfulness correspond to improved cognitive status and a more positive attitude toward treatment for mental illness. It is of great value to promote MBCT in female patients with schizophrenia.

3.
Toxicol Appl Pharmacol ; 447: 116088, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35644267

RESUMO

An ultra-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS) method for the simultaneous determination of Crocin-I and its primary metabolites Crocetin was established, and a comparison of metabolic characteristics in vivo is made to Crocin-I and Crocetin in normoxic and hypoxic rats after intragastric administration. The acute hypoxic rat model was established by simulating high altitude environment in a hypobaric hypoxia animal experimental chamber. After intragastric administration of 400 mg•kg-1 Crocin-I. UPLC-Q-TOF-MS method was used to detect the plasma concentrations of Crocin-I and Crocetin in plasma at different times. Compared with normoxic rats, the area under the curve (AUC), mean residence time (MRT), time to peak (Tmax), half-life (T1/2) and plasma concentration (Cmax) of plasma Crocin-I in hypoxic rats were significantly increased (P < 0.01). The apparent distribution (Vz/F) and clearance (CLz/F) of plasma Crocin-I in hypoxic rats were significantly decreased (P < 0.01). Under hypoxic conditions, the pharmacokinetic parameters of Crocin-I and its metabolite Crocetin change significantly. The results provide a theoretical basis for the feasibility of Crocin-I for anti-hypoxia treatment in terms of pharmacokinetics and provide an essential experimental basis for optimizing the drug dosing regimen.


Assuntos
Hipóxia , Espectrometria de Massas em Tandem , Animais , Carotenoides , Cromatografia Líquida de Alta Pressão/métodos , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/métodos
4.
Pharmaceuticals (Basel) ; 17(8)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39204090

RESUMO

Crocetin is an aglycone of crocin naturally occurring in saffron and has been proved to have antioxidant, anti-inflammatory, and antibacterial activities. In this experiment, the protective effect of crocetin on vital organs in high-altitude hypoxia rats was studied. Crocetin was prepared from gardenia by the alkaline hydrolysis method, and its reducing ability and free radical scavenging ability were tested. The in vitro anti-hypoxia vitality was studied on PC12 cells. The anti-hypoxic survival time of mice was determined in several models. The acute hypoxic injury rat model was established by simulating the hypoxic environment of 8000 m-high altitude for 24 h, and the anti-hypoxia effect of crocetin was evaluated by intraperitoneal injection with the doses of 10, 20, and 40 mg/kg. The water contents of the brain and lung were determined, and the pathological sections in the brain, lung, heart, liver, and kidney were observed by HE staining. The levels of oxidative stress (SOD, CAT, H2O2, GSH, GSH-Px, MDA) and inflammatory factors (IL-1ß, IL-6, TNF-α, VEGF) in rat brain, lung, heart, liver, and kidney tissues were detected by ELISA. The results indicated that crocetin exhibited strong reducing ability and free radical scavenging ability and could improve the activity of PC12 cells under hypoxia. After intraperitoneal injection with crocetin, the survival time of mice was prolonged, and the pathological damage, oxidative stress, and inflammation in rats' tissue were ameliorated. The protective activity of crocetin on vital organs in high-altitude hypoxia rats may be related to reducing oxidative stress and inhibiting inflammatory response.

5.
Oxid Med Cell Longev ; 2022: 8673728, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693707

RESUMO

Background: Hypoxia exerts pressure on cells and organisms, and this pressure can occur under both pathological and nonpathological conditions. There are many reports confirmed that hydroxytyrosol has good in vitro antioxidant activity, while the research about hydroxytyrosol on hypoxia-mediated cell damage is still unclear. Purpose: The aim of this study was to investigate the effect and mechanism of hydroxytyrosol on hypoxia-mediated cell damage. Methods: We studied the effects of hydroxytyrosol on the content of reactive oxygen species, the change of antioxidant enzymes activity of SOD, CAT, and GSH-Px and the content of oxidation products MDA and GSH, and the changes of cell membrane potential and effect on PI3K/AKT/mTOR-HIF-1α signaling pathway under hypoxia-mediated PC12 cell. Results: PC12 cell treated with hydroxytyrosol abated the cell apoptosis and alleviated the oxidative stress through scavenging of reactive oxygen species, improving the enzyme activity and changing the content of oxidation products and alleviating mitochondria damage. Western blotting confirmed that the mechanism maybe related to the PI3K/AKT/mTOR-HIF-1α signaling pathway. The inhibition experiment confirmed that hydroxytyrosol takes part in the expression of protein PI3K and p-mTOR. Conclusion: Hydroxytyrosol reduced the oxidative stress and resisted the inhibition of PI3K/AKT/mTOR-HIF-1α signaling pathway caused by hypoxia, improved cell apoptosis, and ameliorated the antihypoxia ability of PC12 cells under hypoxia.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Hipóxia Celular , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células PC12 , Álcool Feniletílico/análogos & derivados , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Espécies Reativas de Oxigênio/farmacologia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
6.
Huan Jing Ke Xue ; 42(3): 1361-1371, 2021 Mar 08.
Artigo em Zh | MEDLINE | ID: mdl-33742933

RESUMO

To study the spatial-temporal variation of water environment quality in Hengshui Lake and determine the associated pollution sources, we used historical water monitoring data (from 2000 onwards) and data from 17 sites sampled in 2019 to determine the trophic level index (TLI), comprehensive water quality index (WQI), and water environment quality index (EQI). The results showed that the proportion of monitoring points reaching level Ⅲ increased from 2000 to 2019. The permanganate index, total nitrogen, and total phosphorus were the main water environmental indicators. Spatially, TLI, WQI, and EQI all generally decreased from the south to the middle and west of the lake, and then further decreased towards the northeast. After the establishment of the Hengshui Lake National Nature Reserve, a series of water body protection policies and measures were implemented. These interventions are reflected in reductions in the TLI, WQI, and EQI between 2000 and 2019 by 20.9%, 53.4%, and 49.2%, respectively. However, side seepage and sewage discharge, agricultural non-point source pollutants transported by water diversion, and the decay of plants in the lake present significant challenges for water quality in Hengshui Lake.

7.
Front Pharmacol ; 12: 745683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095483

RESUMO

Crocetin is an aglycone of crocin naturally occurring in saffron and produced in biological systems by hydrolysis of crocin as a bioactive metabolite. It is known to exist in several medicinal plants, the desiccative ripe fruit of the cape jasmine belonging to the Rubiaceae family, and stigmas of the saffron plant of the Iridaceae family. According to modern pharmacological investigations, crocetin possesses cardioprotective, hepatoprotective, neuroprotective, antidepressant, antiviral, anticancer, atherosclerotic, antidiabetic, and memory-enhancing properties. Although poor bioavailability hinders therapeutic applications, derivatization and formulation preparation technologies have broadened the application prospects for crocetin. To promote the research and development of crocetin, we summarized the distribution, preparation and production, total synthesis and derivatization technology, pharmacological activity, pharmacokinetics, drug safety, drug formulations, and preparation of crocetin.

8.
Environ Sci Pollut Res Int ; 27(18): 22935-22945, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32329007

RESUMO

High mercury (Hg) affects biochemical-physiological characteristics of plant leaves such as leaf chlorophyll, causing refractive discontinuity and modifications in leaf spectra. Furthermore, the hyperspectroscopy provides a potential tool for fast non-destructive estimation of leaf Hg. However, there are few studies that have investigated Hg for wetland plants via hyperspectral inversion. In this study, reeds (Phragmites australis) leaf Hg concentration and hyperspectra were measured under different soil Hg treatment. Hg-sensitive parameters were identified by basic spectral transformations and continuous wavelet transformation (CWT). Inversion models were developed using stepwise multiple linear regressions (SMLR), partial least square regression (PLSR), and random forest (RF) to estimate leaf Hg. The results indicated that CWT improved the correlation of hyperspectra and leaf Hg by 0.020-0.227, and R2 of the CWT-related model increased by 0.0557-0.2441. In addition, Hg-sensitive bands were predominant at 600-750 (visible region) and 1500-2300 nm (mid-infrared), and Hg might modify leaves spectra primarily by affecting chlorophyll and water contents. Of the studied models, SMLR using normalized transformation (NR) and CWT (NR-CWT-SMLR) model (R2 = 0.8594, RMSE = 0.0961) and RF using NR and CWT (NR-CWT-RF) model (R2 = 0.8560, RMSE = 0.1062) suited for leaf Hg inversion. For Hg content < 1.0 mg kg-1, the former model was more reliable and accurate. This study provided a method for the estimation of Hg contamination in wetland plant and indicated that model-based hyperspectral inversion was feasible for fast and non-destructive monitoring.


Assuntos
Mercúrio , Solo , Clorofila , Análise dos Mínimos Quadrados , Folhas de Planta
9.
Huan Jing Ke Xue ; 39(1): 415-421, 2018 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-29965709

RESUMO

At the Jiapigou gold mine of the Songhua River upstream, reed leaves (Phragmites australis), soil, and water samples were collected from June (summer) and September (autumn) 2016 for the determination of mercury. Moreover, the mercury concentrations in the air were determined synchronously. Furthermore, the level of mercury pollution in the reed leaves was determined by a single factor pollution index method, and the relationships among mercury concentrations in the reed leaves and environmental factors were analyzed to research the distribution characteristics, influencing factors, and correlations around the gold mining area. The results show that, in terms of spatial distribution, the mercury concentrations in reed leaves, soil, and water gradually decay with the distance from the gold mining area, and the spatial distribution of the mercury concentrations in the air was not obvious. Regarding a temporal distribution, the mercury concentrations in the reed leaves in summer were lower than those in autumn in the heavy pollution areas, while the distribution in the light pollution areas was the opposite, as the mercury concentrations of air and soil in summer were higher than those in autumn. The influence of environmental factors on the mercury concentrations in the reed leaves was soil > air > water. In addition, after stopping gold mining and processing using mercury, the mercury source in the area was the soil.


Assuntos
Mercúrio/análise , Mineração , Poaceae/química , Poluentes do Solo/análise , China , Monitoramento Ambiental , Ouro , Folhas de Planta/química , Rios , Estações do Ano , Solo
10.
PLoS One ; 10(3): e0119650, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25768791

RESUMO

Nature reserves are widely considered as one available strategy for protecting biodiversity, which is threatened by habitat fragmentation, and wildlife extinction. The Chinese government has established a goal of protecting 15% of its land area by 2015. We quantitated the characteristics and distribution of nature reserves in mainland China and evaluated the expansion process for national nature reserves. National nature reserves occupy 64.15% of the total area of nature reserves. Steppe and meadow ecosystem, ocean and seacoast ecosystem, and wild plant nature reserves represent lower percentages, particularly in national nature reserves, in which they comprised 0.76%, 0.54%, and 0.69%, respectively, of the area. Furthermore, medium and small nature reserves compose 92.32% of all nature reserves. The land area under any legal protection has reached 14.80%, although only 9.78% is strictly protected. However, if 9 super-large national nature reserves, located in Southwest and Northwest China were removed, the percentage of strictly protected area decreases to 2.66% of the land area of China. The areas contained in nature reserves in each province are not proportional to the areas of the provinces, particularly for national nature reserves, with higher protection rates in Southwest and Northwest China than in other regions. Of the 31 provinces, 22 provinces feature strict protection of less than 4% of their areas by national nature reserves; these provinces are mainly located in East, Central, South, and North China. Moreover, the unevenness indexes of the distribution of nature reserves and national nature reserves are 0.39 and 0.58, respectively. The construction of nature reserves has entered a steady development stage after a period of rapid expansion in mainland China. In recent years, the total area of national nature reserves has increased slowly, while the total area of nature reserves has not increased, although the number of nature reserves continues increase.


Assuntos
Animais Selvagens/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Animais , Biodiversidade , China , Ecossistema
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