Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Virol ; 98(2): e0195423, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38289102

RESUMO

During the life cycle of mosquito-borne flaviviruses, substantial subgenomic flaviviral RNA (sfRNA) is produced via incomplete degradation of viral genomic RNA by host XRN1. Zika virus (ZIKV) sfRNA has been detected in mosquito and mammalian somatic cells. Human neural progenitor cells (hNPCs) in the developing brain are the major target cells of ZIKV, and antiviral RNA interference (RNAi) plays a critical role in hNPCs. However, whether ZIKV sfRNA was produced in ZIKV-infected hNPCs as well as its function remains not known. In this study, we demonstrate that abundant sfRNA was produced in ZIKV-infected hNPCs. RNA pulldown and mass spectrum assays showed ZIKV sfRNA interacted with host proteins RHA and PACT, both of which are RNA-induced silencing complex (RISC) components. Functionally, ZIKV sfRNA can antagonize RNAi by outcompeting small interfering RNAs (siRNAs) in binding to RHA and PACT. Furthermore, the 3' stem loop (3'SL) of sfRNA was responsible for RISC components binding and RNAi inhibition, and 3'SL can enhance the replication of a viral suppressor of RNAi (VSR)-deficient virus in a RHA- and PACT-dependent manner. More importantly, the ability of binding to RISC components is conversed among multiple flaviviral 3'SLs. Together, our results identified flavivirus 3'SL as a potent VSR in RNA format, highlighting the complexity in virus-host interaction during flavivirus infection.IMPORTANCEZika virus (ZIKV) infection mainly targets human neural progenitor cells (hNPCs) and induces cell death and dysregulated cell-cycle progression, leading to microcephaly and other central nervous system abnormalities. RNA interference (RNAi) plays critical roles during ZIKV infections in hNPCs, and ZIKV has evolved to encode specific viral proteins to antagonize RNAi. Herein, we first show that abundant sfRNA was produced in ZIKV-infected hNPCs in a similar pattern to that in other cells. Importantly, ZIKV sfRNA acts as a potent viral suppressor of RNAi (VSR) by competing with siRNAs for binding RISC components, RHA and PACT. The 3'SL of sfRNA is responsible for binding RISC components, which is a conserved feature among mosquito-borne flaviviruses. As most known VSRs are viral proteins, our findings highlight the importance of viral non-coding RNAs during the antagonism of host RNAi-based antiviral innate immunity.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Humanos , Mamíferos/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Viral/genética , RNA Viral/metabolismo , Complexo de Inativação Induzido por RNA/metabolismo , RNA Subgenômico , Proteínas Virais/metabolismo , Replicação Viral , Zika virus/fisiologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
2.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37150785

RESUMO

A-to-I editing is the most prevalent RNA editing event, which refers to the change of adenosine (A) bases to inosine (I) bases in double-stranded RNAs. Several studies have revealed that A-to-I editing can regulate cellular processes and is associated with various human diseases. Therefore, accurate identification of A-to-I editing sites is crucial for understanding RNA-level (i.e. transcriptional) modifications and their potential roles in molecular functions. To date, various computational approaches for A-to-I editing site identification have been developed; however, their performance is still unsatisfactory and needs further improvement. In this study, we developed a novel stacked-ensemble learning model, ATTIC (A-To-I ediTing predICtor), to accurately identify A-to-I editing sites across three species, including Homo sapiens, Mus musculus and Drosophila melanogaster. We first comprehensively evaluated 37 RNA sequence-derived features combined with 14 popular machine learning algorithms. Then, we selected the optimal base models to build a series of stacked ensemble models. The final ATTIC framework was developed based on the optimal models improved by the feature selection strategy for specific species. Extensive cross-validation and independent tests illustrate that ATTIC outperforms state-of-the-art tools for predicting A-to-I editing sites. We also developed a web server for ATTIC, which is publicly available at http://web.unimelb-bioinfortools.cloud.edu.au/ATTIC/. We anticipate that ATTIC can be utilized as a useful tool to accelerate the identification of A-to-I RNA editing events and help characterize their roles in post-transcriptional regulation.


Assuntos
Drosophila melanogaster , Edição de RNA , Animais , Camundongos , Humanos , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , RNA/genética , Adenosina/genética , Adenosina/metabolismo , Inosina/genética , Inosina/metabolismo
3.
Small ; 20(24): e2309403, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148307

RESUMO

Nanozymes have shown promise for antibacterial applications, but their effectiveness is often hindered by low catalytic performances in physiological conditions and uncontrolled production of hydroxyl radicals (·OH). To address these limitations, a comprehensive approach is presented through the development of an adenosine triphosphate (ATP)-activated cascade reactor (GGPcs). The GGPcs reactor synergistically combines the distinct properties of zeolitic imidazolate framework-8 (ZIF-8) and chitosan-integrated hydrogel microsphere. The ZIF-8 allows for the encapsulation of G-quadruplex/hemin DNAzyme to achieve ATP-responsive ·OH generation at neutral pH, while the hydrogel microsphere creates a confinement environment that facilitates glucose oxidation and provides a sufficient supply of H2O2. Importantly, the integrated chitosan in the hydrogel microsphere shields ZIF-8 from undesired disruption caused by gluconic acid, ensuring the responsive specificity of ZIF-8 toward ATP. By activating GGPcs with ATP secreted by bacteria, its effectiveness as an antibacterial agent is demonstrated for the on-demand treatment of bacterial infection with minimal side effects. This comprehensive approach has the potential to facilitate the design of advanced nanozyme systems and broaden their biological applications.


Assuntos
Trifosfato de Adenosina , Antibacterianos , Radical Hidroxila , Radical Hidroxila/metabolismo , Trifosfato de Adenosina/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Quitosana/química , Quitosana/farmacologia , Microesferas , Peróxido de Hidrogênio/química , Zeolitas/química , Zeolitas/farmacologia
4.
Bioorg Chem ; 147: 107400, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688196

RESUMO

Although certain members of the Ubiquitin-specific peptidases (USPs) have been recognized as promising therapeutic targets for various diseases, research progress regarding USP21 has been relatively sluggish in its early stages. USP21 is a crucial member of the USPs subfamily, involved in diverse cellular processes such as apoptosis, DNA repair, and signal transduction. Research findings from the past decade demonstrate that USP21 mediates the deubiquitination of multiple well-known target proteins associated with critical cellular processes relevant to both disease and homeostasis, particularly in various cancers.This reviewcomprehensively summarizes the structure and biological functions of USP21 with an emphasis on its role in tumorigenesis, and elucidates the advances on the discovery of tens of small-molecule inhibitors targeting USP21, which suggests that targeting USP21 may represent a potential strategy for cancer therapy.


Assuntos
Neoplasias , Ubiquitina Tiolesterase , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Ubiquitina Tiolesterase/antagonistas & inibidores , Ubiquitina Tiolesterase/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Animais , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Estrutura Molecular
5.
Cell Mol Biol Lett ; 29(1): 32, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443798

RESUMO

RNA-binding proteins (RBPs) are kinds of proteins with either singular or multiple RNA-binding domains (RBDs), and they can assembly into ribonucleic acid-protein complexes, which mediate transportation, editing, splicing, stabilization, translational efficiency, or epigenetic modifications of their binding RNA partners, and thereby modulate various physiological and pathological processes. CUG-BP, Elav-like family 1 (CELF1) is a member of the CELF family of RBPs with high affinity to the GU-rich elements in mRNA, and thus exerting control over critical processes including mRNA splicing, translation, and decay. Mounting studies support that CELF1 is correlated with occurrence, genesis and development and represents a potential therapeutical target for these malignant diseases. Herein, we present the structure and function of CELF1, outline its role and regulatory mechanisms in varieties of homeostasis and diseases, summarize the identified CELF1 regulators and their structure-activity relationships, and prospect the current challenges and their solutions during studies on CELF1 functions and corresponding drug discovery, which will facilitate the establishment of a targeted regulatory network for CELF1 in diseases and advance CELF1 as a potential drug target for disease therapy.


Assuntos
Descoberta de Drogas , Epigênese Genética , Homeostase , RNA , RNA Mensageiro
6.
Nano Lett ; 23(18): 8690-8696, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37695701

RESUMO

Conduction electron spins interacting with magnetic impurity spins can mediate an interlayer exchange interaction, namely, the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction. This discovery opened the way to significant technological developments in the field of magnetic storage and spintronics. So far, the RKKY-type interlayer interaction has been found to construct symmetric coupling of magnetism; however, the asymmetric counterpart remains unexplored. Here we report unprecedented RKKY-type interlayer Dzyaloshinskii-Moriya interaction (DMI) in synthetic magnets, exhibiting a damped oscillatory feature. This asymmetric interlayer interaction is found to be dramatically dependent on the intermediate coupling layer. By introducing the Fert-Lévy model to the trilayer system, we reveal that the in-plane inversion symmetry breaking plays a pivotal role for generating interlayer DMI and the RKKY oscillation is an intrinsic behavior in metallic multilayers. Our finding fills up the empty block for RKKY-type asymmetric interlayer exchange coupling in comparison to the well-known (symmetric) RKKY-type interlayer exchange coupling.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38417886

RESUMO

BACKGROUND: Inadequate sleep behaviors may confer a higher risk of premature death, however, evidence in patients with chronic noncommunicable disease (NCD) is scarce. To investigate the relationship between sleep duration and mortality from all-cause and heart diseases in NCD patients from a prospective cohort. METHODS: Totally, 14,171 participants with at least one NCD, including 8275 with hypertension, 7547 with high cholesterol, 4065 with diabetes, and 5815 with chronic renal failure were enrolled from the National Health and Nutrition Examination Survey during 2005-2014. Cox proportional hazard models were performed to estimate the hazard ratio (HR) for sleep duration and mortality after adjusting for potential confounding factors. RESULTS: After a median follow-up of 9 years, 2514 all-cause deaths were identified. Compared with sleeping 7-8 h/day, sleeping over 8 h/day was significantly associated with a higher risk of all-cause mortality, where the multivariable-HRs were 1.29 (1.11, 1.50) for hypertension, 1.23 (1.01, 1.51) for high cholesterol, 1.44 (1.13, 1.82) for diabetes, and 1.36 (1.10, 1.68) for chronic renal failure. Similar patterns were observed for heart disease mortality. A nonlinear association was detected between sleep duration and mortality in patients with NCD. Age modified the association in patients with hypertension (P-interaction: 0.036). Trouble sleeping modified the association in patients with diabetes (P-interaction: 0.042). CONCLUSIONS: Long sleep duration was associated with higher risks of all-cause and heart disease mortality in patients with chronic NCD. Our findings highlight that improving sleep behaviors may decrease the risk of premature deaths and help to NCD tertiary prevention.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Cardiopatias , Hipertensão , Falência Renal Crônica , Doenças não Transmissíveis , Humanos , Doenças não Transmissíveis/epidemiologia , Duração do Sono , Estudos de Coortes , Estudos Prospectivos , Inquéritos Nutricionais , Fatores de Risco , Sono , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia , Colesterol , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
8.
J Am Chem Soc ; 145(22): 11927-11932, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37224289

RESUMO

The asymmetric total synthesis of (-)-retigeranic acid A was described, which relies on a crucial reductive skeletal rearrangement cascade for the controllable assembly of diverse angular triquinane subunits. Taken together with an intramolecular Michael/aldol cyclization, an ODI-[5 + 2] cycloaddition/pinacol rearrangement cascade, a Wolff ring contraction and a stereoselective HAT reduction, our synthetic approach has enabled the access to (-)-retigeranic acid A in a concise and practical manner.

9.
Nano Lett ; 22(12): 4646-4653, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35583209

RESUMO

As the core of spintronics, the transport of spin aims at a low-dissipation data process. The pure spin current transmission carried by magnons in antiferromagnetic insulators is natively endowed with superiority such as long-distance propagation and ultrafast speed. However, the traditional control of magnon transport in an antiferromagnet via a magnetic field or temperature variation adds critical inconvenience to practical applications. Controlling magnon transport by electric methods is a promising way to overcome such embarrassment and to promote the development of energy-efficient antiferromagnetic logic. Here, the experimental realization of an electric field-induced piezoelectric strain-controlled magnon spin current transmission through the antiferromagnetic insulator in the Y3Fe5O12/Cr2O3/Pt trilayer is reported. An efficient and nonvolatile manipulation of magnon propagation/blocking is achieved by changing the relative direction between the Néel vector and spin polarization, which is tuned by ferroelastic strain from the piezoelectric substrate. The piezoelectric strain-controlled antiferromagnetic magnon transport opens an avenue for the exploitation of antiferromagnet-based spin/magnon transistors with ultrahigh energy efficiency.

10.
J Am Chem Soc ; 144(6): 2495-2500, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35112847

RESUMO

A hydrogen atom transfer (HAT)-initiated Dowd-Beckwith rearrangement reaction was developed, which enables the efficient assembly of diversely functionalized polyquinane frameworks. By incorporation of an iridium-catalyzed regio- and enantioselective hydrogenation and a diastereocontrolled ODI-[5+2] cycloaddition/pinacol rearrangement cascade reaction, the asymmetric total syntheses of eight tetraquinane natural products, including (-)-crinipellins A-F and (-)-dihydrocrinipellins A and B, have been achieved in a concise and divergent manner.

11.
Biotechnol Appl Biochem ; 69(5): 2240-2248, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34775631

RESUMO

Maltogenic amylase CoMA from Corallococcus sp. strain EGB catalyzes the hydrolysis and transglycosylation of maltooligosaccharides and soluble starch into maltose, the sole hydrolysate. This process yields pure maltose with potentially wide applications. Here, we identified and evaluated the role of phenylalanine 314 (F314), a key amino acid located near the active center, in the catalytic activities of the CoMA. Site-directed mutagenesis analysis showed that the activity of a F314L mutant on potato starch substrate decreased to 26% of that of wild-type protein. Compared with the wild-type, F314L exhibited similar substrate specificity, hydrolysis pattern, pH, and temperature requirements. Circular dichroism spectrum data showed that the F314L mutation did not affect the structure of the folded protein. In addition, kinetic analysis demonstrated that F314L exhibited an increased Km value with lower substrate affinity. Homology modeling showed that the benzene ring structure of F314L was involved in π-π conjugation, which might potentially affect the affinity of CoMA toward starch. Taken together, these data demonstrated that F314 is essential for the hydrolytic activity of the CoMA from Corallococcus sp. strain EGB.


Assuntos
Maltose , Myxococcales , Humanos , Maltose/química , Cinética , Fenilalanina , Coma , Myxococcales/química , Myxococcales/genética , Myxococcales/metabolismo , Hidrólise , Amido/química , Especificidade por Substrato
12.
Sensors (Basel) ; 22(9)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35590820

RESUMO

Soil water content (SWC) is a critical indicator for engineering construction, crop production, and the hydrologic cycle. The rapid and accurate assessment of SWC is of great importance. At present, digital images are becoming increasingly popular in environmental monitoring and soil property analysis owing to the advantages of non-destructiveness, cheapness, and high-efficiency. However, the capture of high-quality digital image and effective color information acquisition is challenging. For this reason, a photographic platform with an integrated experimental structure configuration was designed to yield high-quality soil images. The detrimental parameters of the platform including type and intensity of the light source and the camera shooting angle were determined after systematic exploration. A new method based on Gaussian fitting gray histogram for extracting RGB image feature parameters was proposed and validated. The correlation between 21 characteristic parameters of five color spaces (RGB, HLS, CIEXYZ, CIELAB, and CIELUV) and SWC was investigated. The model for the relationship between characteristic parameters and SWC was constructed by using least squares regression (LSR), stepwise regression (STR), and partial least squares regression (PLSR). Findings showed that the camera platform equipped with 45° illumination D65 light source, 90° shooting angle, 1900~2500 lx surface illumination, and operating at ambient temperature difference of 5 °C could produce highly reproducible and stable soil color information. The effects of image scale had a great influence on color feature extraction. The entire area of soil image, i.e., 3,000,000 pixels, was chosen in conjunction with a new method for obtaining color features, which is beneficial to eliminate the interference of uneven lightness and micro-topography of soil samples. For the five color spaces and related 21 characteristic parameters, RGB and CIEXYZ spaces and characteristic parameter of lightness both exhibited the strongest correlation with SWC. The PLSR model based on soil specimen images ID had an excellent predictive accuracy and the best stability (R2 = 0.999, RMSE = 0.236). This study showed the potential of the application of color information of digital images to predict SWC in agriculture and geotechnical engineering.


Assuntos
Fotografação , Solo , Agricultura , Cor , Distribuição Normal , Solo/química , Água/química
13.
Geriatr Nurs ; 43: 113-123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34864295

RESUMO

INTRODUCTION: Filial piety is an important cultural value in aging societies. However, mixed findings were identified regarding its influence on caregiver burden. The purpose of this meta-analysis was to clarify the relationships between filial concepts and caregiver burden. METHOD: Twelve databases on filial piety, filial obligation, and caregiver burden among adult children prior to January, 2020 were systematically cross-culturally reviewed. RESULTS: Twelve studies were finalized for analysis. Fixed effect models indicated that stronger filial piety was significantly correlated (r = -.23) or associated with (ß = -.27) less caregiver burden. However, no significant relationship between filial obligation and caregiver burden was revealed by random effect models. CONCLUSION: Stronger filial piety may lessen caregiver burden. Therefore, filial piety should be assessed and supported in adult child caregivers, particularly in Eastern cultures. However, the concept of filial piety and its tools should be updated transculturally. PROSPERO Registration Number: CRD42020161969.


Assuntos
Filhos Adultos , Sobrecarga do Cuidador , Envelhecimento , Cuidadores , Humanos
14.
Nano Lett ; 20(5): 3299-3305, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32282217

RESUMO

Magnetic skyrmions are vortex-like spin textures with nontrivial spin topology and novel physical properties that show promise as an essential building block for novel spintronic applications. Skyrmions in synthetic antiferromagnets (SAF) have been proposed long-term to have many advantages than those in ferromagnetic materials, which suffer from fundamental limits for size and efficient manipulation. Thus, experimental realization of skyrmions in SAF is intensely pursued. Here we show the observation of zero-field stable magnetic skyrmions at room temperature in SAF [Co/Pd]/Ru/[Co/Pd] multilayers with Lorentz transmission electron microscope, where uncompensated moments of the SAF provide a medium for the skyrmion characterization. Isolated skyrmions and high-density skyrmions via magnetic field and electromagnetic coordinated methods have been observed, respectively. These created high-density skyrmions maintain at zero-field even when both the current and magnetic field are removed. The use of skyrmions in SAF would advance the process toward practical nonvolatile memories based on spin topology.

15.
Molecules ; 25(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202848

RESUMO

This study aimed to isolate, prepare and identify the main flavonoids from a standardized Smilax glabra flavonoids extract (SGF) using preparative HPLC, MS, 1H NMR and 13C NMR, determine the contents of these flavonoids using UPLC, then compare their pharmacological activities in vitro. We obtained six flavonoids from SGF: astilbin (18.10%), neoastilbin (11.04%), isoastilbin (5.03%), neoisoastilbin (4.09%), engeletin (2.58%) and (-)-epicatechin (1.77%). The antioxidant activity of six flavonoids were evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2'-Azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS+) radical scavenging activity and ferric reducing antioxidant power (FRAP). In addition, the anti-inflammatory activity of six flavonoids were evaluated by determining the production of cytokines (IL-1ß, IL-6), nitric oxide (NO) using enzyme linked immunosorbent assay and the NF-κB p65 expression using Western blotting in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results showed that (-)-epicatechin, astilbin, neoastilbin, isoastilbin and neoisoastilbin had strong antioxidant activities, not only in DPPH and ABTS+ radicals scavenging capacities, but in FRAP system. Furthermore, all the six flavonoids could significantly inhibit the secretion of IL-1ß, IL-6, NO (p < 0.01) and the protein expression of NF-κB p-p65 (p < 0.01) in LPS-stimulated RAW264.7 cells. This study preliminarily verified the antioxidant and anti-inflammatory activities of six flavonoids in S. glabra.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Smilax/química , Animais , Anti-Inflamatórios/química , Antioxidantes/química , Benzotiazóis/química , Compostos de Bifenilo/química , Catequina/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonóis/química , Glicosídeos/química , Lipopolissacarídeos , Espectroscopia de Ressonância Magnética , Camundongos , Picratos/química , Células RAW 264.7 , Ácidos Sulfônicos/química
16.
Biochem Biophys Res Commun ; 520(2): 385-391, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31606201

RESUMO

Previous studies have shown that sarcopenic obesity is highly prevalent in patients with chronic kidney disease (CKD). Here, the association between CKD and sarcopenic obesity were investigated. The 5/6 nephrectomy was performed to establish CKD in mice. Fluorescence-activated cell sorting (FACS), quantitative real-time PCR, ELISA kits assay, immunohistochemistry, and cell proliferation assay were carried out to investigate the condition of muscle loss and fatty infiltration were in CKD mice and the origin of adipocytes. Muscle atrophy occurred and adipogenic gene expression, Perilipin and FABP4 were markedly increased in the hind limb muscle of CKD mice. Results indicated that fibro/adipogenic progenitors (FAPs) are the precursor of adipocytes in the muscle of CKD mice. Meanwhile, the content of extracellular matrix protein CCN1 was notably increased in serum of CKD patients with sarcopenic obesity which was also found in muscle and serum of CKD mice. CCN1 induced the differentiation of FAPs into adipocytes. These results suggest that CKD mice are susceptible to sarcopenic obesity. CCN1 may be a novel activator of the differentiation of FAPs in CKD muscle.


Assuntos
Adipócitos/patologia , Proteína Rica em Cisteína 61/sangue , Proteína Rica em Cisteína 61/metabolismo , Músculo Esquelético/patologia , Insuficiência Renal Crônica/patologia , Adipogenia , Idoso , Animais , Diferenciação Celular , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Nefrectomia , Insuficiência Renal Crônica/metabolismo , Células-Tronco/citologia , Células-Tronco/patologia
17.
Small ; : e1801203, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29943392

RESUMO

Fiber-shaped supercapacitors with improved specific capacitance and high rate capability are a promising candidate as power supply for smart textiles. However, the synergistic interaction between conductive filaments and active nanomaterials remains a crucial challenge, especially when hydrothermal or electrochemical deposition is used to produce a core (fiber)-shell (active materials) fibrous structure. On the other hand, although 2D pseudocapacitive materials, e.g., Ti3 C2 T x (MXene), have demonstrated high volumetric capacitance, high electrical conductivity, and hydrophilic characteristics, MXene-based electrodes normally suffer from poor rate capability owing to the sheet restacking especially when the loading level is high and solid-state gel is used as electrolyte. Herein, by hosting MXene nanosheets (Ti3 C2 T x ) in the corridor of a scrolled carbon nanotube (CNT) scaffold, a MXene/CNT fiber with helical structure is successfully fabricated. These features offer open spaces for rapid ion diffusion and guarantee fast electron transport. The solid-state supercapacitor based on such hybrid fibers with gel electrolyte coating exhibits a volumetric capacitance of 22.7 F cm-3 at 0.1 A cm-3 with capacitance retention of 84% at current density of 1.0 A cm-3 (19.1 F cm-3 ), improved volumetric energy density of 2.55 mWh cm-3 at the power density of 45.9 mW cm-3 , and excellent mechanical robustness.

18.
BMC Complement Altern Med ; 14: 321, 2014 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25174844

RESUMO

BACKGROUND: Allicin, a primary ingredient of garlic, has been proposed to possess cardioprotective properties, which are commonly mediated by improved endothelial function. METHODS: To investigate the effect and mechanism of allicin on the apoptosis of human umbilical vein endothelial cells (HUVECs), we used Propidium iodide (PI) staining and Annexin V/ PI staining assays to establish a model of oxidative stress apoptosis induced by H2O2. MTT, RT-PCR and western-blot assays were used to detect the effects and mechanism of allicin on the model. RESULTS: PI staining, Annexin V/ PI staining assays and morphological assessment suggest that the cell death induced by 0.5 mM H2O2 is primarily apoptotic. Conversely, allicin reverses the effect of H2O2 on cell death, suggesting a role in protecting HUVECs from apoptosis. We demonstrated that H2O2 activates PARP cleavage, reduces pro-Caspase-3 levels and activates Bax expression; however, allicin inhibits each of these apoptotic signaling indicators. Allicin also reduces the levels of malondialdehyde and increases the levels of superoxide dismutase, nitric oxide release and endothelial nitric oxide synthase mRNA, but has no significant effect on inducible nitric oxide synthase mRNA levels. CONCLUSION: These results demonstrate that allicin has powerful effects in protecting HUVECs from apoptosis and suggest that protection occurs via a mechanism involving the protection from H2O2-mediated oxidative stress.


Assuntos
Apoptose/efeitos dos fármacos , Alho/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Ácidos Sulfínicos/farmacologia , Caspase 3/metabolismo , Dissulfetos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína X Associada a bcl-2/metabolismo
19.
Animals (Basel) ; 14(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38338151

RESUMO

Zygote arrest-1 (Zar1) and Wilms' tumor 1 (Wt1) play an important role in oogenesis, with the latter also involved in testicular development and gender differentiation. Here, Lczar1 and Lcwt1b were identified in Asian seabass (Lates calcarifer), a hermaphrodite fish, as the valuable model for studying sex differentiation. The cloned cDNA fragments of Lczar1 were 1192 bp, encoding 336 amino acids, and contained a zinc-binding domain, while those of Lcwt1b cDNA were 1521 bp, encoding a peptide of 423 amino acids with a Zn finger domain belonging to Wt1b family. RT-qPCR analysis showed that Lczar1 mRNA was exclusively expressed in the ovary, while Lcwt1b mRNA was majorly expressed in the gonads in a higher amount in the testis than in the ovary. In situ hybridization results showed that Lczar1 mRNA was mainly concentrated in oogonia and oocytes at early stages in the ovary, but were undetectable in the testis. Lcwt1b mRNA was localized not only in gonadal somatic cells (the testis and ovary), but also in female and male germ cells in the early developmental stages, such as those of previtellogenic oocytes, spermatogonia, spermatocytes and spermatids. These results indicated that Lczar1 and Lcwt1b possibly play roles in gonadal development. Therefore, the findings of this study will provide a basis for clarifying the mechanism of Lczar1 and Lcwt1b in regulating germ cell development and the sex reversal of Asian seabass and even other hermaphroditic species.

20.
Microorganisms ; 12(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38930536

RESUMO

Licorice (Glycyrrhiza glabra) is a plant of the genus Glycyrrhiza in the family Fabaceae/Leguminosae and is a renowned natural herb with a long history of medicinal use dating back to ancient times. Glycyrrhizin (GLY), the main active component of licorice, serves as a widely utilized therapeutic agent in clinical practice. GLY exhibits diverse medicinal properties, including anti-inflammatory, antibacterial, antiviral, antitumor, immunomodulatory, intestinal environment maintenance, and liver protection effects. However, current research primarily emphasizes GLY's antiviral activity, while providing limited insight into its antibacterial properties. GLY demonstrates a broad spectrum of antibacterial activity via inhibiting the growth of bacteria by targeting bacterial enzymes, impacting cell membrane formation, and altering membrane permeability. Moreover, GLY can also bolster host immunity by activating pertinent immune pathways, thereby enhancing pathogen clearance. This paper reviews GLY's inhibitory mechanisms against various pathogenic bacteria-induced pathological changes, its role as a high-mobility group box 1 inhibitor in immune regulation, and its efficacy in combating diseases caused by pathogenic bacteria. Furthermore, combining GLY with other antibiotics reduces the minimum inhibitory concentration, potentially aiding in the clinical development of combination therapies against drug-resistant bacteria. Sources of information were searched using PubMed, Web of Science, Science Direct, and GreenMedical for the keywords "licorice", "Glycyrrhizin", "antibacterial", "anti-inflammatory", "HMGB1", and combinations thereof, mainly from articles published from 1979 to 2024, with no language restrictions. Screening was carried out by one author and supplemented by others. Papers with experimental flaws in their experimental design and papers that did not meet expectations (antifungal papers, etc.) were excluded.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA