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1.
Cereb Cortex ; 34(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39042032

RESUMO

Delay discounting refers to the tendency of individuals to devalue future rewards as the delay in their receipt increases over time. Previous studies have indicated that future self-continuity correlates with delay discounting rates. However, the neural basis underlying the relationship between future self-continuity and delay discounting is not clear. To address this question, we used voxel-based morphometry and resting-state functional connectivity analyses to investigate the neural basis underlying the association between future self-continuity and delay discounting. Behavioral result showed that future self-continuity was positively associated with delay discounting. Voxel-based morphometry analysis result indicated that gray matter volume in the right dorsal anterior insula was positively correlated with future self-continuity. Resting-state functional connectivity analysis found that functional connectivity between the right dorsal anterior insula and anterior cingulate cortex was positively associated with future self-continuity. Mediation analysis showed that the right dorsal anterior insula-right anterior cingulate cortex functional connectivity partially mediated the relationship between future self-continuity and delay discounting. These results suggested that right dorsal anterior insula-right anterior cingulate cortex functional connectivity could be the neural basis underlying the association between future self-continuity and delay discounting. In summary, the study provided novel insights into how future self-continuity affected delay discounting and offers new explanations from a neural perspective.


Assuntos
Desvalorização pelo Atraso , Giro do Cíngulo , Córtex Insular , Imageamento por Ressonância Magnética , Humanos , Masculino , Desvalorização pelo Atraso/fisiologia , Giro do Cíngulo/fisiologia , Giro do Cíngulo/diagnóstico por imagem , Feminino , Adulto Jovem , Córtex Insular/fisiologia , Córtex Insular/diagnóstico por imagem , Adulto , Vias Neurais/fisiologia , Vias Neurais/diagnóstico por imagem , Mapeamento Encefálico , Recompensa
2.
Small ; 20(14): e2306308, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37990392

RESUMO

Stable plating/stripping of Zn metal anode remains a great challenge owing to uncontrollable dendrite growth and side reactions. Ion-sieving separators is a unique and promising solution, that possess Zn2+ permeability and promote Zn2+ transport, can effectively alleviate the abovementioned problems. Ion-sieving on glass fiber separator by deposition of oxygen-deficient SiOx layer via active screen plasma technology is achieved. While having chemical composition similar to the glass fiber, the SiOx nanoparticles contain oxygen-rich vacancies that promoted dissociation of the adsorbed water and generation of the hydroxyl groups. The negatively-charged hydroxylated SiOx layer can repel SO4 2- and attract Zn2+, which can alleviate the side reactions. The strong interplay between hydroxyl groups and Zn2+ can boost Zn affinity and yield fast Zn2+ transport. Consequently, the SiOx-deposited GF separator enabled dendrite-free Zn deposition morphology, which displays lower overpotential of 18 mV and longer cycling life over 2000 h for Zn symmetric cell. Such a separator can also be easily scaled up to prepare the high-performance large-area (4 × 6 cm2) pouch Zn-based devices, showing remarkable flexibility and practicality.

3.
Theor Appl Genet ; 137(1): 23, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231256

RESUMO

KEY MESSAGE: Integrated QTL mapping and WGCNA condense the potential gene regulatory network involved in oil accumulation. A glycosyl hydrolases gene (GhHSD1) for oil biosynthesis was confirmed in Arabidopsis, which will provide useful knowledge to understand the functional mechanism of oil biosynthesis in cotton. Cotton is an economical source of edible oil for the food industry. The genetic mechanism that regulates oil biosynthesis in cottonseeds is essential for the genetic enhancement of oil content (OC). To explore the functional genomics of OC, this study utilized an interspecific backcross inbred line population to dissect the quantitative trait locus (QTL) interlinked with OC. In total, nine OC QTLs were identified, four of which were novel, and each QTL explained 3.62-34.73% of the phenotypic variation of OC. The comprehensive transcript profiling of developing cottonseeds revealed 3,646 core genes differentially expressed in both inbred parents. Functional enrichment analysis determined 43 genes were annotated with oil biosynthesis processes. Implementation of weighted gene co-expression network analysis showed that 803 differential genes had a significant correlation with the OC phenotype. Further integrated analysis identified seven important genes located in OC QTLs. Of which, the GhHSD1 gene located in stable QTL qOC-Dt3-1 exhibited the highest functional linkages with the other network genes. Phylogenetic analysis showed significant evolutionary differences in the HSD1 sequences between oilseed- and starch- crops. Furthermore, the overexpression of GhHSD1 in Arabidopsis yielded almost 6.78% higher seed oil. This study not only uncovers important genetic loci for oil accumulation in cottonseed, but also provides a set of new candidate genes that potentially influence the oil biosynthesis pathway in cottonseed.


Assuntos
Arabidopsis , Gossypium , Gossypium/genética , Óleo de Sementes de Algodão , Filogenia , Genômica
4.
Cereb Cortex ; 33(6): 2655-2668, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35699604

RESUMO

Sleep deprivation (SD) may lead to the development of fear- and anxiety-related emotional disorders. However, the neural mechanisms underlying the effects of SD on fear acquisition are unclear. Here, we tested whether and how SD influences the behavioral and neural manifestations of fear acquisition. We found that subjective fear ratings and objective fear indices (skin conductance response [SCR]) in the SD group were greater than those in the control group during fear acquisition, suggesting that SD facilitated fear acquisition (nSD = 18 and ncontrol = 23 for self-reported rating analysis; nSD = 10 and ncontrol = 10 for SCR analysis). Neuroimaging data showed that the SD group exhibited stronger activity in the left basolateral amygdala (BLA) and left superficial amygdala (SFA). Moreover, the left BLA activity, which positively correlated with the objective fear indices, significantly mediated the effect of SD on fear acquisition. Together, the present findings indicate that SD facilitates fear acquisition by augmenting threat-specific encoding in the BLA, which may be a potential biomarker of the risk of developing fear-related disorders under traumatic and distressing situations.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Humanos , Complexo Nuclear Basolateral da Amígdala/fisiologia , Privação do Sono/diagnóstico por imagem , Tonsila do Cerebelo/diagnóstico por imagem , Medo/fisiologia , Emoções
5.
Anal Chem ; 95(19): 7676-7684, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37129316

RESUMO

Herein, we report a fluorescence strategy for the homogeneous and simultaneous analysis of urine miRNA-375 and miRNA-148a. The target miRNAs in urine bonded the devised dumbbell-shaped "C-Ag+-C" and "T-Hg2+-T" hairpin structures that could trigger cascade enzyme-free amplification. Then, the fluorescent CdTe quantum dots (QDs) and carbon dots (CDs) could selectively recognize Ag+ and Hg2+, to quantify the dual miRNAs concurrently. Under optimized conditions, the linear range was from 0.1 to 1000 fM and the limits of detection (LOD) for dual miRNAs reached 30 and 25 aM, respectively. The practicality was further evaluated with 45 clinical urine samples including prostate cancer (PC) and other patients, and the results were consistent with the clinical polymerase chain reaction (PCR) kit and ultrasonic and pathological findings. The receiver operating characteristic (ROC) curve analysis showed that the estimates of the area under the curve (AUC) were 0.739 for the serum prostate-specific antigen (PSA) and 0.941 for miRNA-375 and 0.946 for miRNA-148a. The sensitivity and specificity reached 75 and 100% for miRNA-375 and 71 and 94% for miRNA-148a, respectively, which was better than serum PSA. This strategy constructed a reliable system for dual miRNA detection in urine samples and proposed new insights into the rapid and noninvasive diagnosis of PC.


Assuntos
Compostos de Cádmio , MicroRNAs , Neoplasias da Próstata , Pontos Quânticos , Masculino , Humanos , MicroRNAs/análise , Antígeno Prostático Específico , Compostos de Cádmio/química , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/urina , Pontos Quânticos/química , Telúrio/química , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/urina
6.
Cereb Cortex ; 32(3): 540-553, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-34297795

RESUMO

The novel coronavirus (COVID-19) pandemic has led to a surge in mental distress and fear-related disorders, including posttraumatic stress disorder (PTSD). Fear-related disorders are characterized by dysregulations in fear and the associated neural pathways. In the present study, we examined whether individual variations in the fear neural connectome can predict fear-related symptoms during the COVID-19 pandemic. Using machine learning algorithms and back-propagation artificial neural network (BP-ANN) deep learning algorithms, we demonstrated that the intrinsic neural connectome before the COVID-19 pandemic could predict who would develop high fear-related symptoms at the peak of the COVID-19 pandemic in China (Accuracy rate = 75.00%, Sensitivity rate = 65.83%, Specificity rate = 84.17%). More importantly, prediction models could accurately predict the level of fear-related symptoms during the COVID-19 pandemic by using the prepandemic connectome state, in which the functional connectivity of lvmPFC (left ventromedial prefrontal cortex)-rdlPFC (right dorsolateral), rdACC (right dorsal anterior cingulate cortex)-left insula, lAMY (left amygdala)-lHip (left hippocampus) and lAMY-lsgACC (left subgenual cingulate cortex) was contributed to the robust prediction. The current study capitalized on prepandemic data of the neural connectome of fear to predict participants who would develop high fear-related symptoms in COVID-19 pandemic, suggesting that individual variations in the intrinsic organization of the fear circuits represent a neurofunctional marker that renders subjects vulnerable to experience high levels of fear during the COVID-19 pandemic.


Assuntos
Encéfalo/diagnóstico por imagem , COVID-19/epidemiologia , COVID-19/psicologia , Medo/psicologia , Rede Nervosa/diagnóstico por imagem , Adolescente , Adulto , Encéfalo/fisiologia , Estudos de Coortes , Medo/fisiologia , Feminino , Seguimentos , Previsões , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/fisiologia , Pandemias , Estudos Prospectivos , Adulto Jovem
7.
Nanotechnology ; 33(15)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34972097

RESUMO

In realistic applications, silver nanowires (AgNWs) are encapsulated in optoelectrical devices to function as transparent conductors and electrodes. Environmental stressors along with the essential electrical stress are inevitably harmful to the AgNWs inside the devices. Herein, to investigate the degradation behavior discrepancy between materials-level and device-level tests, we adopted pseudo-module to mimic the encapsulation. The pseudo-module allows the application of electrical stress and facilitates the interim specimen access for materials characterization through assembly-disassembly. Indoor accelerated and outdoor weathering tests with applied electrical stress to the pseudo-module encapsulated AgNW networks were performed. The impaired optoelectrical properties and morphological changes of AgNWs due to multiple or individual stressor(s) are investigated. Results indicate UVA exposure at elevated temperature coupled with electrical stress is responsible for the electrical failure of AgNW networks. Sulfidation that depresses optical transparency of AgNW networks is prone to occur at lower temperature. This work provides unambiguous degradation behaviors of AgNWs inside encapsulants, helping to improve the design of AgNWs related optoelectrical devices in the applications of solar irradiation environments.

8.
Cereb Cortex ; 31(8): 3846-3855, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33839771

RESUMO

The temporal decision model of procrastination has proposed that outcome value and task aversiveness are two separate aspects accounting for procrastination. If true, the human brain is likely to implicate separate neural pathways to mediate the effect of outcome value and task aversiveness on procrastination. Outcome value is plausibly constructed via a hippocampus-based pathway because of the hippocampus's unique role in episodic prospection. In contrast, task aversiveness might be represented through an amygdala-involved pathway. In the current study, participants underwent fMRI scanning when viewing both tasks and future outcomes, without any experimental instruction imposed. The results revealed that outcome value increased activations in the caudate, and suppressed procrastination through a hippocampus-caudate pathway. In contrast, task aversiveness increased activations in the anterior insula, and increased procrastination via an amygdala-insula pathway. In sum, this study demonstrates that people can incorporate both outcome value and task aversiveness into task valuation to decide whether to procrastinate or not; and it elucidates the separate neural pathways via which this occurs.


Assuntos
Tomada de Decisões/fisiologia , Vias Neurais/fisiologia , Procrastinação , Tonsila do Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Feminino , Hipocampo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Motivação , Neostriado/fisiologia , Desempenho Psicomotor/fisiologia , Adulto Jovem
9.
J Biochem Mol Toxicol ; 35(5): e22731, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33512038

RESUMO

Scutebarbatine A (SBT-A), a diterpenoid alkaloid found in the root of Scutellaria barbata D. Don, has been reported to induce the apoptosis of A549 cells. In this study, we investigated the antitumor activity of SBT-A in human hepatocellular carcinoma (HCC) cells and the potential underlying mechanisms. Our results showed that SBT-A inhibited the growth of HCC cells in a dose-dependent manner. SBT-A treatment caused cell cycle arrest and decreased the expression of cyclin B1, cyclin D1, p-Cdc2, and p-Cdc25C. SBT-A triggered cell apoptosis via a caspase-dependent pathway, and cell viability was partially restored by pretreatment with the pan-caspase inhibitor Z-VAD-FMK. In HCC cells, treatment with SBT-A increased the phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2), c-Jun N-terminal kinase 1 and 2 (JNK1/2), and p38 mitogen-activated protein kinase (p38 MAPK). Moreover, SBT-A activated endoplasmic reticulum (ER) stress through the upregulation of protein kinase RNA-like ER kinase (PERK), activating transcription factor 4 (ATF-4), and CCAAT-enhancer-binding protein (C/EBP) homologous protein (CHOP). Our data indicate that SBT-A inhibits the proliferation of HCC cells and triggers their apoptosis via the activation of MAPK and ER stress. SBT-A is a potential agent for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Citotoxinas/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Naftóis/farmacocinética , Proteínas de Neoplasias/metabolismo , Niacina/farmacocinética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia
10.
J Environ Sci (China) ; 88: 59-71, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862080

RESUMO

The existence of electrolytes in aquatic environment on the photocatalytic performance and coagulation of nanodispersed TiO2 hydrosol and the corresponding photocatalytic alteration were investigated by studying cations (Na+, K+, Ca 2+, Mg2+, and Al3+). The photocatalysis reactions of nano TiO2 with different dosages of electrolytes were measured by monitoring the degradation of Rhodamine B (RhB) under ultraviolet A (UV-A) irradiation over time. The results showed that the photocatalytic performance of TiO2 was improved by the presence of Al3+, while the performance was impaired by the other tested cations. The negative influences of divalent ions on the photocatalytic performance of TiO2 were more significant than monovalent ions. The TiO2 sol dispersed stable at nano scale at low concentration of electrolyte (<0.01 mol/L) with slight change of pH, and coagulated into micro sizes at high concentration of electrolytes (>0.1 mol/L) with larger increase or decrease of pH. The positive effects of Al3+ on the photodegradation rate of RhB might relate to the strong hydrolytic action of Al3+ in aquatic solutions. The photocatalytic processes of TiO2 in the presence of all ions followed the Langmuir-Hinshelwood model, and the reaction kinetic constant was increased with the decrease of pH caused by different cations. These work suggested a new perspective about the relationship between coagulation and photocatalytic performance of TiO2 hydrosols in electrolyte with hydrolysable cations, which demonstrated that TiO2 hydrosols may be suitable as photocatalysts in aquatic environments.


Assuntos
Processos Fotoquímicos , Titânio , Raios Ultravioleta , Catálise , Cátions , Fotólise , Rodaminas/química
11.
Biochem Biophys Res Commun ; 510(1): 20-26, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30683312

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the second major chronic liver disease world-wide and growing. Current medical treatment of NAFLD is not effective, and there is an urgent need to find new effective drugs. Liraglutide is now the first-line treatment for type 2 diabetes mellitus (T2DM) with promise, according to recent reports, to mitigate the fatty degeneration of the liver. The investigators of the current study discern if liraglutide reduces non-alcoholic fatty liver disease (NAFLD) induced by a high-fat diet using mice via modulating Kupffer cells M2 polarization in the liver. The mice underwent four weeks of intraperitoneal injections of liraglutide (0.6 mg/kg body weight). In the NAFLD model used in this study, the liver index, the body weight, and the serum levels of ALT, AST, total cholesterol, and triglycerides were meaningfully improved. In sections using H&E and Oil Red O staining, hepatic steatosis was significantly improved. Liraglutide decreased liver inflammation and the inflammatory properties of Kupffer cells in the NAFLD mouse model and there was a higher ratio of M2/M1 Kupffer cells. In vitro studies found that Liraglutide treatment modulates Kupffer cells to M2-like activation via the cAMP-PKA-STAT3 signaling pathway. The perilous effects of a high-fat diet were alleviated by liraglutide, including hepatic steatosis, by modulating Kupffer cells M2 polarization via the cAMP-PKA-STAT3 signaling pathway. Liraglutide can indeed reverse the negative effects of NAFLD.


Assuntos
Inflamação/prevenção & controle , Células de Kupffer/imunologia , Liraglutida/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diabetes Mellitus Tipo 2/complicações , Dieta Hiperlipídica/efeitos adversos , Células de Kupffer/efeitos dos fármacos , Liraglutida/uso terapêutico , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Fator de Transcrição STAT3/metabolismo
12.
Mol Pharm ; 16(4): 1477-1488, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30807184

RESUMO

The hERG potassium channel (IKr) encoded by human ether-a-go-go-related gene plays an important role in cardiac repolarization. Decreased IKr may lead to long QT syndrome, which subsequently causes torsade de pointes and sudden cardiac death. Previous studies have shown that statins inhibit IKr and are more potent in inhibiting hERG currents when combined with other drugs. Since chemical structure of rosuvastatin is similar to that of several IKr blockers (ibutilide and E-4031), the present study aimed to reveal the mechanism that underlies rosuvastatin-induced hERG current reduction and to evaluate the possibility of cardiac toxicity. The results showed that rosuvastatin reduced hERG currents by accelerating the inactivation and prolonged action potential duration (APD) in hiPSC-CMs. Meanwhile, it was observed that rosuvastatin reduced the expression of the mature hERG. Transcription factor Sp1 was involved in hERG protein downregulation induced by rosuvastatin, and the result was verified by Sp1 siRNA and Sp1 agonist epicatechin. These results indicated that rosuvastatin could potentially inhibit transcription and reduce hERG mRNA expression. The interaction between hERG and heat shock protein was evaluated to study the mechanism of trafficking inhibition through co-immunoprecipitation. We found that rosuvastatin reduces the interaction of heat shock protein 70 (Hsp70) with the hERG protein, thereby affecting the folding of the hERG channel. Additionally, rosuvastatin significantly activates ATF6, which plays a key role in the activation of the unfolded protein response (UPR) pathway. Increased expression of the molecular chaperone calnexin and calreticulin, which are activated by ATF6 to help channel folding, further confirmed UPR activation. Meanwhile, the degradation of the hERG channel was mediated by lysosomes and proteasomes. In conclusion, Rosuvastatin reduced the expression of hERG plasma membrane by two pathways, the first is to disrupt the transport of immature hERG channels to the membrane, and the second is to increase the degradation of mature hERG channels. In addition, Rosuvastatin potently blocked hERG current, delayed cardiac repolarization, and thereby prolonged APDs and QTc intervals. Therefore, caution should be taken when rosuvastatin is used in the treatment of hyperlipidemia, especially when combined with drugs that can prolong the QT interval.


Assuntos
Anticolesterolemiantes/farmacologia , Membrana Celular/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Proteólise/efeitos dos fármacos , Rosuvastatina Cálcica/farmacologia , Potenciais de Ação , Membrana Celular/efeitos dos fármacos , Canais de Potássio Éter-A-Go-Go/efeitos dos fármacos , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Transporte Proteico , Resposta a Proteínas não Dobradas
13.
Pharmacol Res ; 148: 104461, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31542404

RESUMO

Intestinal epithelial barrier dysfunction is a key pathology of colitis. Autophagy of epithelial cells maintains homeostasis of the intestinal barrier by inhibiting apoptosis and stimulating degradation of the tight junction protein claudin-2. This study investigated the effects and mechanism of activity of sinensetin, a polymethylated flavonoid isolated from tangerine peel and citrus, on intestinal barrier dysfunction in colitis. Animal model of colitis were established by intracolonic administration of 2, 4, 6-trinitrobenzene sulfonic acid and oral treatment with dextran sulfate sodium. Epithelial barrier function was evaluated by measuring the serum recovery of fluorescein isothiocyanate-4 kD dextran in vivo and transepithelial electrical resistance in Caco-2 cells, respectively. Epithelial cell autophagy assayed by autophagosome formation and expression of autophagy-related protein. Sinensetin reversed colitis-associated increase in intestinal permeability, significantly promoted epithelial cell autophagy, and further decreased epithelial cell apoptosis, and reduced mucosal claudin-2. Sinenstetin alleviated colitis symptoms rats and mice with colitis. Knockdown of 5' adenosine monophosphate-activated protein kinase (AMPK) reversed the promotion of epithelial autophagy by sinensetin. In conclusion, sinensetin significantly alleviated intestinal barrier dysfunction in colitis by promoting epithelial cell autophagy, and further inhibiting apoptosis and promoting claudin-2 degradation. The results highlighted novel potential benefits of sinensetin in colitis.


Assuntos
Autofagia/efeitos dos fármacos , Colite/tratamento farmacológico , Células Epiteliais/efeitos dos fármacos , Flavonoides/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Células CACO-2 , Claudina-2/metabolismo , Colite/metabolismo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo
14.
Phytother Res ; 33(1): 130-148, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30346043

RESUMO

A fundamental element of acute lung injury (ALI) is the inflammatory response, which can affect the entire respiratory system, including the respiratory tract and alveoli. Berberine has gained attention because of its anti-inflammatory effects. Nuclear factor-erythroid 2-related factor 2 (Nrf2) and endoplasmic reticulum (ER) stress are involved in lung injury. Nrf2 also acts as a protein kinase-like ER kinase (PERK) substrate in heart disease. Therefore, this study investigated the effect of berberine against lipopolysaccharide (LPS)-induced ALI and the role of the PERK-mediated Nrf2/HO-1 signaling axis. Berberine promoted Nrf2 nuclear translocation and phosphorylation in vitro. After LPS stimulation, this effect was further enhanced, whereas inflammatory factor (IL-6 and IL-8) release and reactive oxygen species generation were significantly decreased. Berberine effectively alleviated lung injury by reducing lung edema and neutrophil infiltration. Berberine also significantly reduced histopathological inflammatory changes via inhibition of ER stress and activation of Nrf2 signaling. Thapsigargin-induced ER stress and small interference RNA (siRNA)-mediated Nrf2 inhibition abrogated the protective effects of berberine in vitro, whereas siRNA-mediated suppression of ER stress and sulforaphane-induced Nrf2 activation further improved those effects. Importantly, ER stress induction led to Nrf2 activation, whereas PERK depletion partly reduced the level of Nrf2 phosphorylation and translocation in LPS-induced cells. Therefore, berberine inhibits LPS-induced ALI through the PERK-mediated Nrf2/HO-1 signaling axis.


Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Berberina/uso terapêutico , Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Berberina/farmacologia , Humanos , Lipopolissacarídeos , Masculino , Transdução de Sinais
15.
Entropy (Basel) ; 21(3)2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33267041

RESUMO

Mobile sensors are widely used in indoor positioning in recent years, but most methods require cumbersome calibration for precise positioning results, thus the paper proposes a new unsupervised indoor positioning (UIP) without cumbersome calibration. UIP takes advantage of environment features in indoor environments, as some indoor locations have their signatures. UIP considers these signatures as the landmarks, and combines dead reckoning with them in a simultaneous localization and mapping (SLAM) frame to reduce positioning errors and convergence time. The test results prove that the system can achieve accurate indoor positioning, which highlights its prospect as an unconventional method of indoor positioning.

16.
Neuroimage ; 172: 461-469, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29378319

RESUMO

Sleep deprivation (SD) has been associated with cognitive and emotional disruptions, however its impact on the acquisition of fear and subsequent fear memory consolidation remain unknown. To address this question, we measured human brain activity before and after fear acquisition under conditions of 24 h sleep deprivation versus normal sleep using resting-state functional magnetic resonance imaging (rs-fMRI). Additionally, we explored whether the fear acquisition-induced change of brain activity during the fear memory consolidation window can be predicted by subjective fear ratings and autonomic fear response, assessed by skin conductance responses (SCR) during acquisition. Behaviorally, the SD group demonstrated increased subjective and autonomic fear responses compared to controls at the stage of fear acquisition. During the stage of fear consolidation, the SD group displayed decreased ventromedial prefrontal cortex (vmPFC) activity and concomitantly increased amygdala activity. Moreover, in the SD group fear acquisition-induced brain activity changes in amygdala were positively correlated with both, subjective and autonomic fear indices during acquisition, whereas in controls changes vmPFC activity were positively correlated with fear indices during acquisition. Together, the present findings suggested that SD may weaken the top-down ability of the vmPFC to regulate amygdala activity during fear memory consolidation. Moreover, subjective and objective fear at fear acquisition stage can predict the change of brain activity in amygdala in fear memory consolidation following SD.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Medo/fisiologia , Consolidação da Memória/fisiologia , Córtex Pré-Frontal/fisiopatologia , Privação do Sono/fisiopatologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
17.
Plant Cell Physiol ; 59(12): 2476-2489, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30165667

RESUMO

Nutrient element deprivation, such as iron (Fe) deficiency stress, is a major factor limiting plant survival and proliferation in marginal soils. To cope with a low Fe environment, plants have evolved elaborate mechanisms underlying Fe homeostasis via intricate transcriptional and post-transcriptional regulation. Here, we characterized the Fe deficiency-inducible MYB transcription factor MdMYB58 in apple plants. Overexpressing MdMYB58 resulted in the accumulation of Fe in the root of transgenic Arabidopsis and apple calli when they were exposed to low Fe available conditions. Further investigation revealed that MdMYB58 bound to the promoter of MdMATE43, and its homolog FRD3 in Arabidopsis. Transient expression and stable transgenic assays in apple calli indicated that MdMYB58 transcriptionally repressed MdMATE43 mRNA, as well as FRD3 in Arabidopsis. Interestingly, AtMYB58, the homolog of MdMYB58, possessed higher binding activities to MdMATE43 and FRD3, which suggests a potentially conserved feature of MYB58 binding to MATE transporters in plants. Additionally, MYB-MATE-mediated regulation of Fe homeostasis may be related to the PYE-related Fe deficiency regulatory network via MdSAT1, a member of the IVa subfamily of bHLH transcription factors. Co-overexpression of MdSAT1 competitively weakened MdMYB58-overexpression induced repression of MdMATE43 transcript abundancy by protein-protein interaction. Taken together, the newly identified MYB-bHLH transcription factor expands our understanding of multilevel molecular mechanisms that plants use to coordinate Fe demand with Fe uptake, transport, and tissue partitioning under low Fe conditions.


Assuntos
Homeostase , Ferro/metabolismo , Malus/metabolismo , Regiões Promotoras Genéticas , Arabidopsis , Proteínas de Arabidopsis , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Malus/genética , Proteínas de Membrana Transportadoras , Modelos Biológicos , Proteínas de Plantas , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Transcrição Gênica
18.
Biochem Biophys Res Commun ; 505(2): 523-529, 2018 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-30269815

RESUMO

Liraglutide, a glucagon-like peptide-1 (GLP-1) analogue that has recently become the first-line treatment for type 2 diabetes mellitus (T2DM), has also been reported to decrease fatty degeneration of the liver. The purpose of this study is to explore whether liraglutide improves high-fat diet-induced non-alcoholic fatty liver disease (NAFLD) in mice through inhibiting the NLRP3 inflammasome in the liver. After daily intraperitoneal injection of liraglutide (0.6 mg/kg body weight) for four weeks, the liver, liver/body weight, serum levels of ALT, AST, total cholesterol, triglycerides and LDL were significantly decreased in a high-fat diet-induced NAFLD mouse model. The hepatic steatosis among sections of H&E and Oil Red O staining was also markedly reduced after treatment with liraglutide. The expressions of NLRP3 inflammasome components (including NLRP3, ASC, and caspase-1) in the liver of mice after treatment with liraglutide were decreased substantially. In vitro studies found that the mitochondrial dysfunction in Kupffer cells induced by palmitic acid was attenuated, and the protein levels of NLRP3, ASC and caspase-1 were also decrease markedly. These results demonstrate that liraglutide was able to alleviate high-fat diet-induced hepatic steatosis via inhibiting NLRP3 inflammasome activation, suggesting that liraglutide is a potent drug that can reverse the pathological hallmarks of NAFLD.


Assuntos
Inflamassomos/efeitos dos fármacos , Liraglutida/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Glicemia/efeitos dos fármacos , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , Inflamassomos/metabolismo , Insulina/farmacologia , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia
19.
Phys Chem Chem Phys ; 20(12): 8247-8266, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29528060

RESUMO

The mechanical properties of organic/inorganic composites can be highly dependent on the interfacial interactions. In this work, with organic polymers intercalated into the interlayer of inorganic calcium silicate hydrate (C-S-H), the primary binding phase of Portland cement, great ductility improvement is obtained for the nanocomposites. Employing reactive molecular dynamics, the simulation results indicate that strong interfacial interactions between the polymers and the substrate contribute greatly to strengthening the materials, when C-S-H/poly ethylene glycol (PEG), C-S-H/poly acrylic acid (PAA), and C-S-H/poly vinyl alcohol (PVA) were subject to uniaxial tension along different lattice directions. In the x and z direction tensile processes, the Si-OCa bonds of the C-S-H gel, which were elongated and broken to form Si-OH and Ca-OH, play a critical role in loading resistance, while the incorporation of polymers bridged the neighboring silicate sheets, and activated more the hydrolytic reactions at the interfaces to avoid strain localization, thus increasing the tensile strength and postponing the fracture. On the other hand, Si-O-Si bonds of C-S-H mainly take the load when tension was applied along the y direction. During the post-yield stage, rearrangements of silicate tetrahedra occurred to prevent rapid damage. The polymer intercalation further elongates this post-yield period by forming interfacial Si-O-C bonds, which promote rearrangements and improve the connectivity of the defective silicate morphology, significantly improving the ductility. Among the polymers, PEG exhibits the strongest interaction with C-S-H, and thus C-S-H/PEG possesses the highest ductility. We expect that the molecular-scale mechanisms interpreted here will shed new light on the stress-activated chemical interactions at the organic/inorganic interfaces, and help eliminate the brittleness of cement-based materials on a genetic level.

20.
Chem Geol ; 460: 25-36, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28827855

RESUMO

Recent topography measurements of gypsum dissolution have not reported the absolute dissolution rates, but instead focus on the rates of formation and growth of etch pits. In this study, the in situ absolute retreat rates of gypsum (010) cleavage surfaces at etch pits, at cleavage steps, and at apparently defect-free portions of the surface are measured in flowing water by reflection digital holographic microscopy. Observations made on randomly sampled fields of view on seven different cleavage surfaces reveal a range of local dissolution rates, the local rate being determined by the topographical features at which material is removed. Four characteristic types of topographical activity are observed: 1) smooth regions, free of etch pits or other noticeable defects, where dissolution rates are relatively low; 2) shallow, wide etch pits bounded by faceted walls which grow gradually at rates somewhat greater than in smooth regions; 3) narrow, deep etch pits which form and grow throughout the observation period at rates that exceed those at the shallow etch pits; and 4) relatively few, submicrometer cleavage steps which move in a wave-like manner and yield local dissolution fluxes that are about five times greater than at etch pits. Molar dissolution rates at all topographical features except submicrometer steps can be aggregated into a continuous, mildly bimodal distribution with a mean of 3.0 µmolm-2 s-1 and a standard deviation of 0.7 µmolm-2 s-1.

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