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1.
J Cell Mol Med ; 28(3): e18058, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38098246

RESUMO

Ionizing radiation (IR)-induced intestinal injury is usually accompanied by high lethality. Intestinal stem cells (ISCs) are critical and responsible for the regeneration of the damaged intestine. Astragalus polysaccharide (APS), one of the main active ingredients of Astragalus membranaceus (AM), has a variety of biological functions. This study was aimed to investigate the potential effects of APS on IR-induced intestine injury via promoting the regeneration of ISCs. We have established models of IR-induced intestinal injury and our results showed that APS played great radioprotective effects on the intestine. APS improved the survival rate of irradiated mice, reversed the radiation damage of intestinal tissue, increased the survival rate of intestinal crypts, the number of ISCs and the expression of intestinal tight junction-related proteins after IR. Moreover, APS promoted the cell viability while inhibited the apoptosis of MODE-K. Through organoid experiments, we found that APS promoted the regeneration of ISCs. Remarkably, the results of network pharmacology, RNA sequencing and RT-PCR assays showed that APS significantly upregulated the HIF-1 signalling pathway, and HIF-1 inhibitor destroyed the radioprotection of APS. Our findings suggested that APS promotes the regeneration of ISCs through HIF-1 signalling pathway, and it may be an effective radioprotective agent for IR-induced intestinal injury.


Assuntos
Astrágalo , Transdução de Sinais , Camundongos , Animais , Polissacarídeos/farmacologia , Intestinos , Células-Tronco
2.
BMC Infect Dis ; 23(1): 472, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37461013

RESUMO

BACKGROUND: Patients with malignancy are at a higher risk of developing nosocomial infections. However, limited studies investigated the clinical features and prognostic factors of nosocomial infections due to fungi in cancer patients. Herein, this study aims to investigate the clinical characteristics of in-hospital fungal infections and develop a nomogram to predict the risk of in-hospital death during fungal infection of hospitalized cancer patients. METHODS: This retrospective observational study enrolled cancer patients who experienced in-hospital fungal infections between September 2013 and September 2021. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of in-hospital mortality. Variables demonstrating significant statistical differences in the multivariate analysis were utilized to construct a nomogram for personalized prediction of in-hospital death risk associated with nosocomial fungal infections. The predictive performance of the nomogram was evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis. RESULTS: A total of 216 participants were included in the study, of which 57 experienced in-hospital death. C.albicans was identified as the most prevalent fungal species (68.0%). Respiratory infection accounted for the highest proportion of fungal infections (59.0%), followed by intra-abdominal infection (8.8%). The multivariate regression analysis revealed that Eastern Cooperative Oncology Group Performance Status (ECOG-PS) 3-4 (odds ratio [OR] = 6.08, 95% confidence interval [CI]: 2.04-18.12), pulmonary metastases (OR = 2.76, 95%CI: 1.11-6.85), thrombocytopenia (OR = 2.58, 95%CI: 1.21-5.47), hypoalbuminemia (OR = 2.44, 95%CI: 1.22-4.90), and mechanical ventilation (OR = 2.64, 95%CI: 1.03-6.73) were independent risk factors of in-hospital death. A nomogram based on the identified risk factors was developed to predict the individual probability of in-hospital mortality. The nomogram demonstrated satisfactory performance in terms of classification ability (area under the curve [AUC]: 0.759), calibration ability, and net clinical benefit. CONCLUSIONS: Fungi-related nosocomial infections are prevalent among cancer patients and are associated with poor prognosis. The constructed nomogram provides an invaluable tool for oncologists, enabling them to make timely and informed clinical decisions that offer substantial net clinical benefit to patients.


Assuntos
Infecção Hospitalar , Neoplasias Pulmonares , Humanos , Mortalidade Hospitalar , Nomogramas , Estudos Retrospectivos , Prognóstico
3.
Phytother Res ; 37(10): 4557-4571, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37427974

RESUMO

Cryptotanshinone (CPT), a major biological active ingredient extracted from root of Salvia miltiorrhiza (Danshen), has shown several pharmacological activities. However, the effect of CPT on radiation-induced lung fibrosis (RILF) is unknown. In this study, we explored the protective effects of CPT on RILF from gut-lung axis angle, specifically focusing on the bile acid (BA)-gut microbiota axis. We found that CPT could inhibit the process of epithelial mesenchymal transformation (EMT) and suppress inflammation to reduce the deposition of extracellular matrix in lung fibrosis in mice induced by radiation. In addition, 16S rDNA gene sequencing and BAs-targeted metabolomics analysis demonstrated that CPT could improve the dysbiosis of gut microbiota and BA metabolites in RILF mice. CPT significantly enriched the proportion of the beneficial genera Enterorhabdus and Akkermansia, and depleted that of Erysipelatoclostridium, which were correlated with increased intestinal levels of several farnesoid X receptor (FXR) natural agonists, such as deoxycholic acid and lithocholic acid, activating the FXR pathway. Taken together, these results suggested that CPT can regulate radiation-induced disruption of gut microbiota and BAs metabolism of mice, and reduce the radiation-induced lung inflammation and fibrosis. Thus, CPT may be a promising drug candidate for treating RILF.

4.
Sensors (Basel) ; 23(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37447886

RESUMO

This paper proposes a speech recognition method based on a domain-specific language speech network (DSL-Net) and a confidence decision network (CD-Net). The method involves automatically training a domain-specific dataset, using pre-trained model parameters for migration learning, and obtaining a domain-specific speech model. Importance sampling weights were set for the trained domain-specific speech model, which was then integrated with the trained speech model from the benchmark dataset. This integration automatically expands the lexical content of the model to accommodate the input speech based on the lexicon and language model. The adaptation attempts to address the issue of out-of-vocabulary words that are likely to arise in most realistic scenarios and utilizes external knowledge sources to extend the existing language model. By doing so, the approach enhances the adaptability of the language model in new domains or scenarios and improves the prediction accuracy of the model. For domain-specific vocabulary recognition, a deep fully convolutional neural network (DFCNN) and a candidate temporal classification (CTC)-based approach were employed to achieve effective recognition of domain-specific vocabulary. Furthermore, a confidence-based classifier was added to enhance the accuracy and robustness of the overall approach. In the experiments, the method was tested on a proprietary domain audio dataset and compared with an automatic speech recognition (ASR) system trained on a large-scale dataset. Based on experimental verification, the model achieved an accuracy improvement from 82% to 91% in the medical domain. The inclusion of domain-specific datasets resulted in a 5% to 7% enhancement over the baseline, while the introduction of model confidence further improved the baseline by 3% to 5%. These findings demonstrate the significance of incorporating domain-specific datasets and model confidence in advancing speech recognition technology.


Assuntos
Modelos Teóricos , Redes Neurais de Computação , Interface para o Reconhecimento da Fala , Fala , Percepção da Fala , Conjuntos de Dados como Assunto , Espectrografia do Som
5.
Int J Mol Sci ; 24(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958798

RESUMO

Tetragonia tetragonoides (Pall.) Kuntze (Aizoaceae, 2n = 2x = 32), a vegetable used for both food and medicine, is a halophyte that is widely distributed in the coastal areas of the tropics and subtropics. Saline-alkaline soils and drought stress are two major abiotic stressors that significantly affect the distribution of tropical coastal plants. Abscisic acid-, stress-, and ripening-induced (ASR) proteins belong to a family of plant-specific, small, and hydrophilic proteins with important roles in plant development, growth, and abiotic stress responses. Here, we characterized the ASR gene family from T. tetragonoides, which contained 13 paralogous genes, and divided TtASRs into two subfamilies based on the phylogenetic tree. The TtASR genes were located on two chromosomes, and segmental duplication events were illustrated as the main duplication method. Additionally, the expression levels of TtASRs were induced by multiple abiotic stressors, indicating that this gene family could participate widely in the response to stress. Furthermore, several TtASR genes were cloned and functionally identified using a yeast expression system. Our results indicate that TtASRs play important roles in T. tetragonoides' responses to saline-alkaline soils and drought stress. These findings not only increase our understanding of the role ASRs play in mediating halophyte adaptation to extreme environments but also improve our knowledge of plant ASR protein evolution.


Assuntos
Ácido Abscísico , Aizoaceae , Ácido Abscísico/metabolismo , Secas , Filogenia , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/metabolismo , Solução Salina , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Solo
6.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1463-1482, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005834

RESUMO

Dolomiaea plants are perennial herbs in the Asteraceae family with a long medicinal history. They are rich in chemical constituents, mainly including sesquiterpenes, phenylpropanoids, triterpenes, and steroids. The extracts and chemical constituents of Dolomiaea plants have various pharmacological effects, such as anti-inflammatory, antibacterial, antitumor, anti-gastric ulcer, hepatoprotective and choleretic effects. However, there are few reports on Dolomiaea plants. This study systematically reviewed the research progress on the chemical constituents and pharmacological effects of Dolomiaea plants to provide references for the further development and research of Dolomiaea plants.


Assuntos
Asteraceae , Sesquiterpenos , Triterpenos , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Anti-Inflamatórios , Compostos Fitoquímicos/farmacologia
7.
Nanotechnology ; 33(35)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-33887710

RESUMO

Transforming levulinic acid (LA) toγ-valerolactone (GVL) is a significant route for converting biomass into valuable chemicals. The development of an efficient and robust heterogeneous catalyst for this reaction has aroused great interest. In this work, nitrogen-doped graphene (NG) supported nickel (Ni) based heterogeneous catalyst with excellent activities was successfully synthesized. The Ni/NG catalyst shows outstanding performance for hydrogenation of LA to GVL at a relatively low temperature of 140 °C, which is superior to most of reported heterogeneous catalysts. Further investigations indicate Ni nanoparticles are the active sites and the NG also plays an indispensable role. The catalytic performance is highly depended on the crystallinity, particles sizes and electronic structure of Ni in Ni/NG catalyst, which can be optimized by nitrogen doping. This work affords a new route for designing robust and excellent heterogeneous catalysts by doping method to optimize the support.

8.
Int J Med Sci ; 19(4): 711-728, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35582412

RESUMO

Background: Lipid metabolism plays a pivotal role in cancer progression and metastasis. This study aimed to investigate the prognostic value of lipid metabolism-related genes (LMRGs) in early-stage lung adenocarcinoma (LUAD) and develop a lipid metabolism-related gene prognostic index (LMRGPI) to predict their overall survival (OS) and treatment response. Methods: A total of 774 early-stage LUAD patients were identified from The Cancer Genome Atlas (TCGA, 403 patients) database and Gene Expression Omnibus (GEO, 371 patients) database. The non-negative Matrix Factorization (NMF) algorithm was used to identify different population subtypes based on LMRGs. The Least Absolute Shrinkage and Selection Operator (LASSO) and multivariate Cox regression analyses were used to develop the LMRGPI, with receiver operating characteristic (ROC) curves and concordance index being used to evaluate its performance. The characteristics of mutation landscape, enriched pathways, tumor microenvironment (TME), and treatment response between different LMRGPI groups were also investigated. Results: We identified two population subtypes based on LMRGs in the TCGA-LUAD cohort, with distinct prognosis, TME, and immune status being observed. LMRGPI was developed based on the expression levels of six LMRGs, including ANGPTL4, NPAS2, SLCO1B3, ACOXL, ALOX15, and B3GALNT1. Higher LMRGPI was correlated with poor OS both in TCGA and GSE68465 cohorts. Two nomograms were established to predict the survival probability of early-stage LUAD, with higher consistencies being observed between the predicted and actual OS. Higher LMRGPI was significantly correlated with more frequent TP53 mutation, higher tumor mutation burden (TMB), and up-regulation of CD274. Besides, patients with higher LMRGPI presented unremarkable responses for gefitinib, erlotinib, cisplatin, and vinorelbine, while they tend to have a favorable response for immune checkpoint inhibitors (ICIs). The opposite results were observed in the low-LMRGPI group. Conclusions: We comprehensively investigated the prognostic value of LMRGs in early-stage LUAD. Given its good prognostic ability, LMRGPI could serve as a promising biomarker to predict the OS and treatment response of these patients.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Perfilação da Expressão Gênica , Humanos , Metabolismo dos Lipídeos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Prognóstico , Microambiente Tumoral/genética
9.
Ecotoxicol Environ Saf ; 248: 114341, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36442401

RESUMO

Radiation-induced intestinal damage (RIID) is a serious disease with limited effective treatment. Nuclear explosion, nuclear release, nuclear application and especially radiation therapy are all highly likely to cause radioactive intestinal damage. The intestinal microecology is an organic whole with a symbiotic relationship formed by the interaction between a relatively stable microbial community living in the intestinal tract and the host. Imbalance and disorders of intestinal microecology are related to the occurrence and development of multiple systemic diseases, especially intestinal diseases. Increasing evidence indicates that the gut microbiota and its metabolites play an important role in the pathogenesis and prevention of RIID. Radiation leads to gut microbiota imbalance, including a decrease in the number of beneficial bacteria and an increase in the number of harmful bacteria that cause RIID. In this review, we describe the pathological mechanisms of RIID, the changes in intestinal microbiota, the metabolites induced by radiation, and their mechanism in RIID. Finally, the mechanisms of various methods for regulating the microbiota in the treatment of RIID are summarized.


Assuntos
Microbioma Gastrointestinal , Microbiota , Intestinos
10.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555252

RESUMO

Rett syndrome (RTT) is a severe neurodevelopmental disorder caused by MeCP2 mutations. Nonetheless, the pathophysiological roles of MeCP2 mutations in the etiology of intrinsic cardiac abnormality and sudden death remain unclear. In this study, we performed a detailed functional studies (calcium and electrophysiological analysis) and RNA-sequencing-based transcriptome analysis of a pair of isogenic RTT female patient-specific induced pluripotent stem-cell-derived cardiomyocytes (iPSC-CMs) that expressed either MeCP2wildtype or MeCP2mutant allele and iPSC-CMs from a non-affected female control. The observations were further confirmed by additional experiments, including Wnt signaling inhibitor treatment, siRNA-based gene silencing, and ion channel blockade. Compared with MeCP2wildtype and control iPSC-CMs, MeCP2mutant iPSC-CMs exhibited prolonged action potential and increased frequency of spontaneous early after polarization. RNA sequencing analysis revealed up-regulation of various Wnt family genes in MeCP2mutant iPSC-CMs. Treatment of MeCP2mutant iPSC-CMs with a Wnt inhibitor XAV939 significantly decreased the ß-catenin protein level and CACN1AC expression and ameliorated their abnormal electrophysiological properties. In summary, our data provide novel insight into the contribution of activation of the Wnt/ß-catenin signaling cascade to the cardiac abnormalities associated with MeCP2 mutations in RTT.


Assuntos
Células-Tronco Pluripotentes Induzidas , Síndrome de Rett , Humanos , Feminino , Síndrome de Rett/metabolismo , Via de Sinalização Wnt , Miócitos Cardíacos/metabolismo , Linhagem Celular , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Mutação
11.
Entropy (Basel) ; 24(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35885135

RESUMO

In this article, a mixed finite element method for thermally coupled, stationary incompressible MHD problems with physical parameters dependent on temperature in the Lipschitz domain is considered. Due to the variable coefficients of the MHD model, the nonlinearity of the system is increased. A stationary discrete scheme based on the coefficients dependent temperature is proposed, in which the magnetic equation is approximated by Nédélec edge elements, and the thermal and Navier-Stokes equations are approximated by the mixed finite elements. We rigorously establish the optimal error estimates for velocity, pressure, temperature, magnetic induction and Lagrange multiplier with the hypothesis of a low regularity for the exact solution. Finally, a numerical experiment is provided to illustrate the performance and convergence rates of our numerical scheme.

12.
Nano Lett ; 20(10): 7304-7312, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32866018

RESUMO

Surface-enhanced Raman scattering (SERS) technique with naturally born analyte identification capability can achieve ultrahigh sensitivity. However, the sensitivity and quantification capability of SERS are assumed to be mutually exclusive. Here, we prohibit the formation of the ultrasensitive SERS sites to achieve a high quantification capability through separating the gold (Au) nanorods from approaching each other with thick metal organic framework (MOF) shells. The sensitivity decrease caused by the absence of the ultrasensitive SERS sites is compensated by the analyte enrichment function of a slippery surface. The porous MOF shell around the Au nanorod only allows analytes smaller than the pore size to approach the Au nanorods and contribute to the SERS spectrum within the complex sample, greatly enhancing the analyte identification capability. Overall, we have demonstrated an integrated SERS platform with analyte enrichment and analyte filtration function, realizing sensitive, quantitative, and size selective analyte identification in complex environments.


Assuntos
Nanopartículas Metálicas , Nanotubos , Filtração , Ouro , Análise Espectral Raman
13.
Nanotechnology ; 31(13): 135401, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-31816611

RESUMO

Developing low cost and highly robust electrocatalysts for oxygen evolution reaction, hydrogen evolution reaction (HER), and oxygen reduction reaction (ORR) is of great importance for the efficient conversion of sustainable energy sources. Herein, we report a facile pyrolysis strategy for the controllable synthesis of NiCo@NiS/S-CNTs with NiCo@NiS nanoparticles anchored on sulfur-doped carbon nanotubes (CNTs). The obtained NiCo@NiS/S-CNT electrocatalyst exhibits excellent dual-functional catalytic activities under an alkaline condition, an ORR performance with an onset potential of -30 mV, and a half-wave potential of -150 mV (versus Ag/AgCl) while the overpotential for the HER is -1.16 V (versus Ag/AgCl) at a current density of 10 mA cm-2. It was found that the incorporation of sulfur can regulate the electronic structure of CNTs to accelerate the electron transfer performance and generate new catalytic sites, thus contributing to greatly enhancing both the activity and stability of the catalytic process. This work provides a promising way for the rational design of efficient and robust catalysts for sustainable energy conversion.

14.
Ecotoxicol Environ Saf ; 168: 378-387, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30396134

RESUMO

A growing number of epidemiological surveys show that PM2.5 is an important promoter for the cardiovascular dysfunction induced by atmospheric pollution. PM2.5 is a complex mixture of solid and liquid airborne particles and its components determine the health risk of PM2.5to a great extent. However, the individual cardiotoxicities of different PM2.5 fractions are still unclear, especially in the cellular level. Here we used the neonatal rat cardiomyocytes (NRCMs) to evaluate the cardiac toxicity of PM2.5 exposure. The cytotoxicities of Total-PM2.5, water soluble components of PM2.5 (WS-PM2.5) and water insoluble components of PM2.5 (WIS-PM2.5), which include the cell viability, cell membrane damage, reactive oxygen species (ROS) generation, were examined with NRCMs in vitro. The results indicated that Total-PM2.5 or WIS-PM2.5 exposure significantly decreased the cell viability, induced the cell membrane damage and increased the ROS level in NRCMs at concentrations above 50 µg/mL. However, WS-PM2.5 exposure could induce the cytotoxicity on NRCMs until the concentration of WS-PM2.5 was raised to a higher concentration (75 µg/mL). Furthermore, the DNA damage was detected in NRCMs after 48 h of exposure with Total-PM2.5, WS-PM2.5 or WIS-PM2.5 (75 µg/mL) and the adverse effects on mitochondrial function and action potentials of NRCMs were detected only both in the Total-PM2.5 and WIS-PM2.5 treatment group. In summary, our project not only estimates the risk of PM2.5 on cardiac cells but also reveal that Total-PM2.5 and WIS-PM2.5 exposure were predominantly associated with the functional cardiotoxicities in NRCMs.


Assuntos
Cardiotoxinas/toxicidade , Miócitos Cardíacos/efeitos dos fármacos , Material Particulado/toxicidade , Animais , Animais Recém-Nascidos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
15.
Langmuir ; 34(25): 7404-7415, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29874461

RESUMO

A series of naphthalimide derivative gelators (G-o, G-m, and G-p) with three molecular isomers as their terminal groups were designed and synthesized. Only G-m and G-p could form stable organogels in some solvents including methanol, acetonitrile, n-hexane, toluene, ethanol, DMSO, DMF, and mixed solvents of acetonitrile/H2O (1/1, v/v). The different self-assembly structures were obtained from the self-assembly process of G-o, G-m, and G-p such as structures like a Chinese chestnut formed by irregular micrometer pieces, microbelts, and microbelt structures mingled with the bird's nest structures which exhibited different surface hydrophobicity with water contact angles of 121-139° due to their different intermolecular noncovalent interactions. To our surprise, G-p acetonitrile solution emitted 492 nm light with a red-shift of 72 nm compared with that emitted from G-o and G-m acetonitrile solution under 350 nm light excitation. Three gelators showed different detection abilities toward metal ions. G-o did not have any ability for sensitive and selective detection toward any ion. In contrast, G-m and G-p could sensitively and selectively detect Hg2+ and Fe3+. The detection limits for Fe3+ and Hg 2+ by G-m were 4.76 × 10-5 M and 7.01 × 10-6 M with the corresponding association constants ( K) of 1.64 × 104 and 3.79 × 104 M-1, respectively. The detection limits for Fe3+ and Hg2+ by G-p were 3.26 × 10-5 and 1.77 × 10-6 M with the corresponding K of 1.44 × 105 and 1.99 × 104 M-1, respectively. More interestingly, the back-titration of SCN- could distinguish Hg2+ from Fe3+. At the same time, xerogels G-m and G-p also exhibited responsiveness toward Fe3+ and Hg2+ through fluorescence changes. The photophysical properties, gel formation, hierarchical structures, surface wettability, and their function in this self-assembly system could be tuned through the molecular isomer effect. This work provides a new research paradigm for molecular isomer tuned supramolecular self-assembly materials from noncovalent interaction to molecular function.

16.
Nanotechnology ; 29(41): 414001, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30052528

RESUMO

Surface-enhanced Raman scattering (SERS) has been recognized as a promising sensing technique in biomedical/biosensing applications and analytical chemistry. Silver (Ag) nanostructures have the strongest SERS enhancement, but suffer from severe enhancement degradation induced by oxidation. Here, we introduce electrochemical reduction of silver oxide to produce Ag SERS substrates on request to partially circumvent the SERS enhancement degradation problem of Ag SERS substrates. Silver oxide nanostructures were first prepared in pure silver citrate aqueous solutions with controllable morphologies depending on the electrodeposition parameters. The transition process from silver oxide to Ag was investigated by density functional theory calculations. Based on the understanding of the transition mechanism, heating treatment, applying reducing agent, and electrochemical reduction were adopted to transform silver oxide to Ag. Notably, no organic agents were introduced neither in the electrodeposition of silver oxide nor electrochemical transformation of silver oxide to Ag. The electrochemical reduction strategy could produce Ag SERS substrates with a 'clean' surface with outstanding SERS performance in a simple as well as cost and time effective manner. Ag SERS substrates can be used in biomedical/biosensing fields. The approach through electrochemical reduction of silver oxide to generate Ag SERS substrate may push forward practical application process of Ag SERS substrates.

17.
Langmuir ; 33(31): 7788-7798, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28718285

RESUMO

Two simple and novel gelators (G-P with pyridine and G-B with benzene) with different C-4 substitution groups on naphthalimide derivatives have been designed and characterized. Two gelators could form organogels in some solvents or mixed solvents. The self-assembly processes of G-P in a mixed solvent of acetonitrile/H2O (1/1, v/v) and G-B in acetonitrile were studied by means of electron microscopy and spectroscopy. The organogel of G-P in the mixed solvent of acetonitrile/H2O (1/1, v/v) formed an intertwined fiber network, and its emission spectrum had an obvious blue shift compared with that of solution. By contrast, the organogel of G-B in acetonitrile formed a straight fiber, and its emission had an obvious red shift compared with that of solution. G-P and G-B were employed in detecting nitroaromatic compounds because of their electron-rich property. G-P is more sensitive and selective toward 2,4,6-trinitrophenol (TNP) compared with G-B. The sensing mechanisms were investigated by 1H NMR spectroscopic experiments and theoretical calculations. From these experimental results, it is proposed that electron transfer occurs from the electron-rich G-P molecule to the electron-deficient TNP because of the possibility of complex formation between G-P and TNP. The G-P molecule could detect TNP in water, organic solvent media, as well as using test strips. It is worth mentioning that the organogel G-P can not only detect TNP but also remove TNP from the solution into the organogel system.

18.
Soft Matter ; 13(20): 3802-3811, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28485752

RESUMO

A thiophene-based hybrid organogel system consisting of complex iridium (Ir) and EuCl3·6H2O was designed and synthesized to realize dual responses to volatile acids and organic amine vapors. The photophysical properties and self-assembly of compound 1 and the hybrid organogel were also studied. Compound 1 could gelate some organic solvents and self-assemble into 3D nanofibers in the gels. The stable hybrid organogel 1-Ir-Eu could be obtained after addition of complex Ir and EuCl3·6H2O. FTIR spectral results showed that the hydrogen bond still remained even upon addition of complex Ir, EuCl3·6H2O, NaOH and CF3COOH to organogel 1. Interestingly, the emission properties of the hybrid organogel 1-Ir-Eu could undergo interconversion between cyan light and red light via addition of NaOH and CF3COOH. The emission properties of xerogel film 1-Ir-Eu obtained in the presence of NaOH could also undergo fast and reversible transition in response to volatile acids such as CF3COOH, formic acid, acetic acid, propionic acid and organic amine vapors such as ammonium hydroxide, Et3N, tripropylamine, and ethylenediamine. The emission spectral change of Ir-Eu in the organogel or xerogel in the presence of base and acid demonstrated the formation of a new complex between complex Ir and EuCl3·6H2O. This dual-response process could be repeated many times. Contact angle experiment results further showed the morphology and internal components of the xerogel film surface in the process of response to gaseous CF3COOH and Et3N. This work provides a method for producing multifunctional supramolecular materials for sensing volatile acids and organic amine vapors.

19.
Biomed Pharmacother ; 170: 115679, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38113632

RESUMO

Bacopaside I (BSI) is a natural compound that is difficult to absorb orally but has been shown to have antidepressant effects. The microbiota-gut-brain axis is involved in the development of depression through the peripheral nervous system, endocrine system, and immune system and may be a key factor in the effect of BSI. Therefore, this study aimed to investigate the potential mechanism of BSI in the treatment of depression via the microbiota-gut-brain axis and to validate it in a fecal microbiota transplantation model. The antidepressant effect of BSI was established in CUMS-induced mice using behavioral tests and measurement of changes in hypothalamicpituitaryadrenal (HPA) axis-related hormones. The improvement of stress-induced gut-brain axis damage by BSI was observed by histopathological sections and enzyme-linked immunosorbent assay (ELISA). 16 S rDNA sequencing analysis indicated that BSI could modulate the abundance of gut microbiota and increase the abundance of probiotic bacteria. We also observed an increase in short-chain fatty acids, particularly acetic acid. In addition, BSI could modulate the disruption of lipid metabolism induced by CUMS. Fecal microbiota transplantation further confirmed that disruption of the microbiota-gut-brain axis is closely associated with the development of depression, and that the microbiota regulated by BSI exerts a partial antidepressant effect. In conclusion, BSI exerts antidepressant effects by remodeling gut microbiota, specifically through the Lactobacillus and Streptococcus-acetic acid-neurotrophin signaling pathways. Furthermore, BSI can repair damage to the gut-brain axis, regulate HPA axis dysfunction, and maintain immune homeostasis.


Assuntos
Microbioma Gastrointestinal , Camundongos , Animais , Depressão/metabolismo , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Acetatos/farmacologia , Estresse Psicológico/metabolismo
20.
Int J Psychophysiol ; 183: 41-52, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36400129

RESUMO

Previous studies found that the reward effect is stronger in more difficult retrieval tasks of item memory. However, it remains unclear whether the effect of reward is influenced by the memory task difficulty level in the source memory. We investigated the effects and neural mechanisms of the processing depth during encoding and rewards at retrieval on the item and source memory using event-related potentials (ERPs). Participants were required to carry out the congruity-judgment (deep processing) and size-judgment (shallow processing) tasks during encoding, and they completed separate object and background tests (half presented with reward) immediately after encoding. The results revealed that congruity-judgment (compare to size-judgment) task had longer response time in encoding phase, and evoked significantly greater reward differences at Prs (the hit rate minus the false alarm rate) in item retrieval, and the reward (relative to no reward) significantly improved recognition accuracy in source retrieval. ERP results also showed that congruity-judgment (compare to size-judgment) task evoked the larger N170, P3a, LPP and a decreased P3b of the stimuli in encoding phase, and elicited the wider distribution of LPC and LPN reward effects (i.e., the average amplitudes under the reward condition were significantly more positive than under the non-reward condition) in item retrieval, and the reward effects at FN400, LPC, and LPN were found only in the congruity-judged items with optimal difficulty in source retrieval. The results suggest that reward at retrieval evoked a greater boost in the congruity-judged stimuli, whether in item or source retrieval, which maybe be related to their optimal retrieval difficulty (Pr is closer to medium 0.50). This meant that the reward is more effective in memory retrieval with optimal difficulty.


Assuntos
Eletroencefalografia , Memória Episódica , Humanos , Eletroencefalografia/métodos , Reconhecimento Psicológico/fisiologia , Memória/fisiologia , Potenciais Evocados/fisiologia , Tempo de Reação/fisiologia , Rememoração Mental/fisiologia
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