Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Food Funct ; 12(20): 9979-9993, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34494629

RESUMO

Currently, drug-induced liver injury caused by acetaminophen (APAP) is the second leading cause of human liver transplantation. The only clinical antidote treatment for APAP-induced liver injury is N-acetyl-L-cysteine (NAC), which has many side effects. Chitooligosaccharides (COS) are processed from naturally occurring chitin through chemical desalting and deproteinization, biological enzymatic hydrolysis and other processes. In this study, we constructed in vitro and in vivo models of APAP-induced liver injury to study COS of two molecular weights (MWs), which are COST (MW ≤ 1000 Da) and COSM (MW ≤ 3000 Da). The results showed that COST and COSM can significantly reduce the levels of serum ALT and AST and liver MDA, TNF-α, IL-1ß and IL-6, and increase the levels and activity of GSH, SOD, GSH-Px and CAT. A mechanistic study found that COST and COSM can significantly reduce the expression of liver CYP2E1, Keap1, p-ASK1/ASK1, p-MKK4/MKK4, p-JNK/JNK, Caspase-3 and Bax and increase the expression of Nrf2, HO-1, eNOS, SOD and Bcl-XL. COST and COSM can inhibit toxic APAP metabolism, inhibit oxidative damage and the apoptosis pathway, increase activation of the liver antioxidant pathway, and ultimately ameliorate APAP-induced liver oxidative damage.

3.
Gut Microbes ; 13(1): 1949095, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34313539

RESUMO

Farnesoid X receptor (FXR) is a nuclear receptor for bile acids (BAs) that is widely expressed in the intestine, liver and kidney. FXR has important regulatory impacts on a wide variety of metabolic pathways (such as glucose, lipid, and sterol metabolism) and has been recognized to ameliorate obesity, liver damage, cholestasis and chronic inflammatory diseases. The types of BAs are complex and diverse. BAs link the intestine with the liver through the enterohepatic circulation. BAs derivatives have entered clinical trials for liver disease. In addition to the liver, the intestine is also targeted by BAs. This article reviews the effects of different BAs on the intestinal tract through the enterohepatic circulation from the perspective of FXR, aiming to elucidate the effects of different BAs on the intestinal tract and lay a foundation for new treatment methods.

4.
J Nanobiotechnology ; 19(1): 189, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162370

RESUMO

BACKGROUND: For certain human cancers, sperm associated antigen 5 (SPAG5) exerts important functions for their development and progression. However, whether RNA interference (RNAi) targeting SPAG5 has antitumor effects has not been determined clinically. RESULTS: The results indicated that Fe-doped chrysotile nanotubes (FeSiNTs) with a relatively uniform outer diameter (15-25 nm) and inner diameter (7-8 nm), and a length of several hundred nanometers, which delivered an siRNA against the SPAG5 oncogene (siSPAG5) efficiently. The nanomaterials were designed to prolong the half-life of siSPAG5 in blood, increase tumor cell-specific uptake, and maximize the efficiency of SPAG5 silencing. In vitro, FeSiNTs carrying siSPAG5 inhibited the growth, migration, and invasion of bladder cancer cells. In vivo, the FeSiNTs inhibited growth and metastasis in three models of bladder tumors (a tail vein injection lung metastatic model, an in-situ bladder cancer model, and a subcutaneous model) with no obvious toxicities. Mechanistically, we showed that FeSiNTs/siSPAG5 repressed PI3K/AKT/mTOR signaling, which suppressed the growth and progression of tumor cells. CONCLUSIONS: The results highlight that FeSiNTs/siSPAG5 caused no activation of the innate immune response nor any systemic toxicity, indicating the possible therapeutic utility of FeSiNTs/siSPAG5 to deliver siSPAG5 to treat bladder cancer.


Assuntos
Asbestos Serpentinas/farmacologia , Proteínas de Ciclo Celular/genética , Nanotubos/química , RNA Interferente Pequeno/química , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Inativação Gênica , Terapia Genética/métodos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Interferência de RNA , Ratos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
5.
Food Funct ; 12(3): 926-951, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33434251

RESUMO

Chitosan oligosaccharides (COSs) are widely used biopolymers that have been studied in relation to a variety of abnormal biological activities in the food and biomedical fields. Since different COS preparation technologies produce COS compounds with different structural characteristics, it has not yet been possible to determine whether one or more chito-oligomers are primarily responsible for the bioactivity of COSs. The inherent biocompatibility, mucosal adhesion and nontoxic nature of COSs are well documented, as is the fact that they are readily absorbed from the intestinal tract, but their structure-activity relationship requires further investigation. This review summarizes the methods used for COS preparation, and the research findings with regard to the antioxidant, anti-inflammatory, anti-obesity, bacteriostatic and antitumour activity of COSs with different structural characteristics. The correlation between the molecular structure and bioactivities of COSs is described, and new insights into their structure-activity relationship are provided.


Assuntos
Quitosana/química , Oligossacarídeos/química , Exoesqueleto/química , Animais , Configuração de Carboidratos
6.
Infect Drug Resist ; 13: 1307-1318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440168

RESUMO

Objective: Vibrio parahaemolyticus is a major diarrhoea-inducing pathogen in coastal areas. In this study, we analysed the pathogenic characteristics of and variation in V. parahaemolyticus isolated from acute diarrhoeal patients in seven hospitals in different areas of southeastern China from 2013 to 2017. Methods: The fecal specimens of patients with acute diarrhoea were collected. The routine microbiological test procedure combining with MALDI Biotyper microbial identification system was carried out to identify the V. parahaemolyticus. Serum agglutination tests, PCR for the detection of virulence-related genes and the Kirby-Bauer method to test for antimicrobial sensitivity were performed. Results: From 2013 to 2017 in southeastern China, a total of 1220 V. parahaemolyticus strains were isolated from 16,504 stool specimens collected from acute diarrhoeal patients, and the annual isolation rate fluctuated between 6.1% and 8.7%. In total, 96.7% of the V. parahaemolyticus isolates were isolated in summer and autumn, mainly in people aged 18-44. Fifty-nine serotypes were identified, and the agglutination rate of the O antigen was 98.5%. From 2014 to 2016, the dominant serotype was O3:K6, while in 2013 and 2017, it was O4:KUT. The serotypes of O3:K6, O4:KUT, O4:K8, O3:KUT, O10:K60, O1:KUT and O1:K36 appeared every year from 2013 to 2017. O4:K6 and OUT:K6 began to appear after 2014 and 2015, respectively. A total of 49.5% of the strains belonged to the pandemic group, which consisted of 26 serotypes. Most isolates were sensitive to common antibiotics, excluding ampicillin. Conclusion: V. parahaemolyticus is still present at a high level in southeastern China. Although the pandemic O3:K6 serotype is predominant, new serotypes continue to emerge, especially the O4:KUT serotype, which exceeded O3:K6 in prevalence in some years. Long-term surveillance is necessary to prevent the outbreak or transmission of this pathogen.

7.
Sci Rep ; 10(1): 766, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964975

RESUMO

The proteasome inhibitor bortezomib is the most successfully applied chemotherapeutic drug for treating multiple myeloma. However, its clinical efficacy reduced due to resistance development. The underlying molecular mechanisms of bortezomib resistance are poorly understood. In this study, by combining in silico analysis and sgRNA library based drug resistance screening assay, we identified SENP2 (Sentrin/SUMO-specific proteases-2) as a bortezomib sensitive gene and found its expression highly downregulated in bortezomib resistant multiple myeloma patient's samples. Furthermore, down regulation of SENP2 in multiple myeloma cell line RPMI8226 alleviated bortezomib induced cell proliferation inhibition and apoptosis, whereas, overexpression of SENP2 sensitized these cells to bortezomib treatment. We further demonstrate that knockdown of SENP2 in RPMI8226 cells increased SUMO2 conjugated IκBα that resulted in the activation of NF-κB. Taken together, we report that silencing of SENP2 and consequent activation of NF-κB through the modulation of IκBα sumoylation as a novel mechanism inducing bortezomib resistance in multiple myeloma.


Assuntos
Bortezomib/farmacologia , Cisteína Endopeptidases/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo/genética , Inibidor de NF-kappaB alfa/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Simulação por Computador , Regulação Neoplásica da Expressão Gênica , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , NF-kappa B/metabolismo , RNA Guia/farmacologia , Transdução de Sinais , Sumoilação
8.
Sci Adv ; 5(9): eaaw6499, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31579820

RESUMO

RNA interference (RNAi) technology can specifically silence the expression of a target gene and has emerged as a promising therapeutic method to treat cancer. In the present study, we showed that natural halloysite nanotube (HNT)-assisted delivery of an active small interfering RNA (siRNA) targeting receptor-interacting protein kinase 4 ( RIPK4 ) efficiently silenced its expression to treat bladder cancer. The HNTs/siRNA complex increased the serum stability of the siRNA, increased its circulation lifetime in blood, and promoted the cellular uptake and tumor accumulation of the siRNA. The siRNA markedly down-regulated RIPK4 expression in bladder cancer cells and bladder tumors, thus inhibiting tumorigenesis and progression in three bladder tumor models (a subcutaneous model, an in situ bladder tumor model, and a lung metastasis model), with no adverse effects. Thus, we revealed a simple but effective method to inhibit bladder cancer using RIPK4 silencing, indicating a promising therapeutic method for bladder cancer.


Assuntos
Portadores de Fármacos , Técnicas de Transferência de Genes , Nanotubos , Proteínas Serina-Treonina Quinases/genética , RNA Interferente Pequeno/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Técnicas de Química Sintética , Modelos Animais de Doenças , Terapia Genética , Humanos , Lisossomos/metabolismo , Camundongos , Modelos Biológicos , Nanotubos/química , Nanotubos/ultraestrutura , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/química , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Sci Rep ; 9(1): 13830, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554904

RESUMO

Both aberrantly expressed mRNAs and micro(mi)RNAs play important roles in cancer cell function, which makes integration analysis difficult. In this study, we first applied master regulator analysisalgorithm and confirmed hsa-miR-4756-3p as a candidate miRNA in triple negative breast cancer (TNBC) patients; hsa-miR-4756-3p could regulate TNBC cell line apoptosis, proliferation, migration, and cell cycle as well as suppress TGF-ß1 signalling andtumour growth. In TNBC, forkhead box protein M1 (FOXM1)was found to be an hsa-miR-4756-3p target gene, and FOXM1 knockout completely inhibited hsa-miR-4756-3p-induced cell migration and metastasis, TGF-ß1 signalling, and epithelial mesenchymal signal activation, which indicated that hsa-miR-4756-3p functions via the FOXM1-TGFß1-EMT axis.


Assuntos
Biologia Computacional/métodos , Proteína Forkhead Box M1/genética , MicroRNAs/genética , Neoplasias de Mama Triplo Negativas/patologia , Regiões 3' não Traduzidas , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Animais , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Pessoa de Meia-Idade , Transplante de Neoplasias , Neoplasias de Mama Triplo Negativas/genética
10.
Sci Rep ; 9(1): 6808, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31048707

RESUMO

DNA purification is essential for the detection of human clinical specimens. A non-destructive, controllable, and low reagent consuming DNA extraction method is described. Negatively charged DNA is absorbed onto a negatively charged montmorillonite to achieve non-destructive DNA extraction based on cation bridge construction and electric double layer formation. Different valence cation modified montmorillonite forms were used to validate the charge-dependent nature of DNA adsorption on montmorillonite. Electric double layer thickness thinning/thickening with the high/lower valence cations exists, and the minerals tended to be sedimentation-stable due to the Van der Waals attraction/electrostatic repulsion. Li-modified montmorillonite with the lowest charge states showed the best DNA adsorption efficiency of 8-10 ng/µg. Charge-dependent regulating research provides a new perspective for controllable DNA extraction and a deep analysis of interface engineering mechanisms.


Assuntos
Argila/química , DNA/química , DNA/isolamento & purificação , Minerais/química , Adsorção , Algoritmos , Cátions , Modelos Teóricos , Eletricidade Estática
11.
Phys Rev Lett ; 116(13): 136802, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27081996

RESUMO

We report the enhancement of the thermoelectric power (TEP) in graphene with extremely low disorder. At high temperature we observe that the TEP is substantially larger than the prediction of the Mott relation, approaching to the hydrodynamic limit due to strong inelastic scattering among the charge carriers. However, closer to room temperature the inelastic carrier-optical-phonon scattering becomes more significant and limits the TEP below the hydrodynamic prediction. We support our observation by employing a Boltzmann theory incorporating disorder, electron interactions, and optical phonons.

12.
Phys Rev Lett ; 116(8): 086603, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26967434

RESUMO

The combination of Rashba spin-orbit coupling and potential disorder induces a random current operator for the edge states of a 2D topological insulator. We prove that charge transport through such an edge is ballistic at any temperature, with or without Luttinger liquid interactions. The solution exploits a mapping to a spin 1/2 in a time-dependent field that preserves the projection along one randomly undulating component (integrable dynamics). Our result is exact and rules out random Rashba backscattering as a source of temperature-dependent transport, absent integrability-breaking terms.

13.
J Phys Condens Matter ; 20(38): 385202, 2008 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-21693821

RESUMO

With the eigenfunctional theory, we study a general interacting electron system, and give a rigorous expression of its ground state energy, which is composed of two parts: one part is contributed by the non-interacting electrons, and the other one is represented by the correlation functions that are controlled by the electron correlation. Moreover, according to the rigorous expression of the ground state energy, an effective scheme beyond the local density approximation of the density functional theory is proposed. As a simple example for a spin-1/2 XXZ chain, under the linear approximation in solving the equation of the phase field, the ground state energy obtained by the present scheme is quite close to that of the Bethe ansatz.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...