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1.
Nature ; 550(7676): 354-359, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-29052630

RESUMO

A long-standing goal of artificial intelligence is an algorithm that learns, tabula rasa, superhuman proficiency in challenging domains. Recently, AlphaGo became the first program to defeat a world champion in the game of Go. The tree search in AlphaGo evaluated positions and selected moves using deep neural networks. These neural networks were trained by supervised learning from human expert moves, and by reinforcement learning from self-play. Here we introduce an algorithm based solely on reinforcement learning, without human data, guidance or domain knowledge beyond game rules. AlphaGo becomes its own teacher: a neural network is trained to predict AlphaGo's own move selections and also the winner of AlphaGo's games. This neural network improves the strength of the tree search, resulting in higher quality move selection and stronger self-play in the next iteration. Starting tabula rasa, our new program AlphaGo Zero achieved superhuman performance, winning 100-0 against the previously published, champion-defeating AlphaGo.


Assuntos
Jogos Recreativos , Software , Aprendizado de Máquina não Supervisionado , Humanos , Redes Neurais de Computação , Reforço Psicológico , Aprendizado de Máquina Supervisionado
2.
Pharm Biol ; 61(1): 1343-1363, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37623313

RESUMO

CONTEXT: Tormentic acid (TA), an effective triterpenoid isolated from Chaenomeles speciosa (Sweet) Nakai (Rosaceae) fruits, exerts an effective treatment for gastric damage. OBJECTIVE: To investigate the gastroprotective effect of TA on indomethacin (IND) damaged GES-1 cells and rats, and explore potential mechanisms. MATERIALS AND METHODS: TA concentrations of 1.563-25 µM were used. Cell proliferation, apoptosis and migration were performed using MTT, colony formation, wound healing, migration, Hoechst staining assays. SD rats were divided into control, IND, TA (1, 2 and 4 mg/kg) + IND groups, once a day for 21 continuous days. Twenty-four hours after the last administration, all groups except the control group were given IND (100 mg/kg) by gavage. Gastric juice parameters, gastric ulcer, gastric blood flow (GBF), blood biochemical parameters and cytokine analysis and gastric mucosal histopathology were detected for 2 h and 6 h after IND oral administration. The mRNA and protein expression of miR-139 and the CXCR4/CXCL12/PLC/PKC/Rho A/MLC pathway were analyzed in the IND-damaged GES-1 cells and gastric tissue of rats. RESULTS: TA might ameliorate the gastric mucosal injury by accelerating the IND-damaged GES-1 cell proliferation and migration, ameliorating GBF, ulcer area and pathologic changes, the redox system and cytokine levels, the gastric juice parameters, elevating the gastric pH in IND damaged rats; suppressed miR-139 mRNA expression, elevated CXCR4 and CXCL12 mRNA and protein expression, p-PLC, p-PKC, Rho A, MLCK and p-MLC protein expression. DISCUSSION AND CONCLUSIONS: TA may have potential use as a clinical drug candidate for gastric mucosal lesion treatment.


Assuntos
MicroRNAs , Triterpenos , Animais , Ratos , Ratos Sprague-Dawley , Frutas , Triterpenos/farmacologia , Citocinas , Quimiocina CXCL12
3.
Environ Res ; 215(Pt 1): 114225, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36063909

RESUMO

People spend most of their time indoors, isolated from the outdoor environment where serious air pollution usually occurs. To what extent outdoor air pollution contributes to their daily personal exposure and inhaled dose? To fill this knowledge gap, an exposure assessment study was conducted for indoor-active university students during a wintertime period of hazy and non-hazy (clear) days in Beijing. Indoor and outdoor fine particulate matter (PM2.5) samples were collected at six indoor microenvironments, and two outdoor environments representing traffic and ambient exposure in the university, respectively, to estimate the personal exposure of students. The average daily personal exposure and poteantial inhaled dose on hazy days (124.8 ± 72.3 µg m-3 and 2.74 ± 1.53 mg) were much higher than that on clear days (57.5 ± 31.9 µg m-3 and 1.26 ± 0.59 mg), indicating a significant influence from the ambient air quality. The indoor PM2.5 concentrations were significantly and positively correlated with the outdoor ones (r = 0.67-0.96) with an FINF (infiltration factor) range of 0.44-0.81 during sampling periods. The outdoor-origin air contributed 68%-95% to the total indoor PM2.5, the average of which was higher during haze events (87%) than clear periods (73%). Correspondingly, outdoor-origin PM2.5 contributed around 105.4 µg m-3 and 2.41 mg (85% and 89%) to the daily exposure and inhaled dose of college students on hazy days, respectively, compared to just 39.2 µg m-3 and 0.95 mg (68% and 75%) on clear days. Our results highlight the significant contribution of outdoor-origin PM2.5 occurred indoor to both the daily personal exposure and inhaled dose due to air pollution filtration between outdoor and indoor environments. These also suggest a continuous effort not only on ambient air quality improvements, but also on environmental friendly building for public health protection with lower exposure.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Humanos , Tamanho da Partícula , Material Particulado/análise , Estudantes , Universidades
4.
BMC Anesthesiol ; 21(1): 193, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34281529

RESUMO

BACKGROUND: This study aims to investigate the risk factors of perioperative neurocognitive disorders (PNDs) mainly including postoperative cognitive dysfunction (POCD) in elderly patients with gastrointestinal tumors, and evaluate its predictive value. METHODS: A total of 222 eligible elderly patients (≥65 years) scheduled for elective gastroenterectomy under general anesthesia were enrolled. The cognitive function assessment was carried out 1 day before surgery and 7 days after surgery. Receiver operating characteristic curve analysis was performed to evaluate the predictive value of risk factors for early POCD. The risk factors for POCD were analyzed using univariate and multivariate logistic regression model. RESULTS: Of all the 222 enrolled patients, 91 (41.0%) developed early POCD and 40 (18.0%) were identified as major POCD within 7 days after the surgery. Visual analogue score (VAS, 1st day, resting) ≥4 (OR = 7.618[3.231-17.962], P < 0.001) and alcohol exposure (OR = 2.398[1.174-4.900], P = 0.016) were independent risk factors for early POCD. VAS score (1st, resting) ≥4 (OR = 13.823[4.779-39.981], P < 0.001), preoperative white blood cell (WBC) levels ≥10 × 10*9/L (OR = 5.548[1.128-26.221], P = 0.035), blood loss ≥500 ml (OR = 3.317[1.094-10.059], P = 0.034), history of hypertension (OR = 3.046[1.267-7.322], P = 0.013), and neutrophil-lymphocyte ratio (NLR) ≥2 (OR = 3.261[1.020-10.419], P = 0.046) were independent risk factors for major POCD. Receiver operating characteristic curve analysis indicated that VAS score (1st day, resting) was a significant predictor for major POCD with a cut-off value of 2.68 and an area under the curve of 0.860 (95% confidence interval: 0.801-0.920, P < 0.001). CONCLUSIONS: The risk factors for early POCD after gastroenterectomy included high VAS score (1st day, resting) and alcohol exposure. High VAS score, preoperative WBC levels ≥10 × 10*9/L, blood loss ≥500 ml, NLR ≥2, and history of hypertension were independent risk factors for major POCD. Among them, VAS score was one of the important predictors.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Neoplasias Gastrointestinais/cirurgia , Transtornos Neurocognitivos/epidemiologia , Complicações Cognitivas Pós-Operatórias/epidemiologia , Idoso , Anestesia Geral/métodos , Feminino , Gastrectomia/métodos , Humanos , Hipertensão/epidemiologia , Masculino , Transtornos Neurocognitivos/etiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco
5.
Biomed Environ Sci ; 32(1): 11-21, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30696535

RESUMO

OBJECTIVE: A strain of Aspergillus niger (A. niger), capable of releasing bound phenolic acids from wheat bran, was isolated. This strain was identified by gene sequence identification. The antioxidant and anti-inflammatory capacity of ferulic acid released from wheat bran by this A. niger strain (FA-WB) were evaluated. METHODS: Molecular identification techniques based on PCR analysis of specific genomic sequences were conducted; antioxidant ability was examined using oxygen radical absorbance capacity (ORAC), cellular antioxidant activity (CAA) assays, and erythrocyte hemolysis assays. RAW264.7 cells were used as a model to detect anti-inflammatory activity. RESULTS: The filamentous fungal isolate was identified to be A. niger. ORAC and CAA assay showed that FA-WB had better antioxidant activity than that of the ferulic acid standard. The erythrocyte hemolysis assay results suggested that FA-WB could attenuate AAPH-induced oxidative stress through inhibition of reactive oxy gen species (ROS) generation. FA-WB could significantly restore the AAPH-induced increase in intracellular antioxidant enzyme activities to normal levels as well as inhibit the intracellular malondialdehyde formation. TNF-a, IL-6, and NO levels indicated that FA-WB can inhibit the inflammation induced by lipopolysaccharide (LPS). CONCLUSION: Ferulic acid released from wheat bran by a new strain of A. niger had good anti-inflammatory activity and better antioxidant ability than standard ferulic acid.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Aspergillus niger/metabolismo , Ácidos Cumáricos/farmacologia , Fibras na Dieta/microbiologia , Animais , Anti-Inflamatórios/metabolismo , Antioxidantes/metabolismo , Aspergillus niger/genética , Aspergillus niger/isolamento & purificação , Ácidos Cumáricos/metabolismo , DNA Fúngico/análise , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Fermentação , Células Hep G2 , Humanos , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Células RAW 264.7 , Ovinos , Fator de Necrose Tumoral alfa/metabolismo
7.
Mar Drugs ; 14(5)2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27153073

RESUMO

An actinomycete strain, H41-59, isolated from sea sediment in a mangrove district, was identified as Streptomyces anandii on the basis of 16S rDNA gene sequence analysis as well as the investigation of its morphological, physiological and biochemical characteristics. Three new ergosterols, ananstreps A-C (1-3), along with ten known ones (4-13), were isolated from the culture broth of this strain. The gross structures of these new compounds were elucidated on the basis of extensive analysis of spectroscopic data, including HR-ESI-MS, and NMR. The cytotoxicities of these isolates against human breast adenocarcinoma cell line MCF-7, human glioblastoma cell line SF-268, and human lung cancer cell line NCI-H460 and their antibacterial activities in inhibiting the growth of Candida albicans and some other pathogenic microorganisms were tested. Compounds 3-8, 10 and 11 displayed cytotoxicity with IC50 values in a range from 13.0 to 27.8 µg/mL. However, all the tested compounds showed no activity on C. albicans and other bacteria at the test concentration of 1 mg/mL with the paper disc diffusion method.


Assuntos
Ergosterol/química , Streptomyces/química , Antibacterianos/química , Antibacterianos/farmacologia , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Ergosterol/farmacologia , Sedimentos Geológicos/microbiologia , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética/métodos , Testes de Sensibilidade Microbiana/métodos , RNA Ribossômico 16S/genética , Streptomyces/genética
8.
Mediators Inflamm ; 2015: 762709, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25892855

RESUMO

AIMS: This study aimed to assess the differential expression of specific B cell subtypes in patients with chronic viral hepatitis. METHODS: The frequencies of differential expression of specific B cell subtypes in patients with chronic viral hepatitis and healthy controls were assessed by flow cytometry using monoclonal antibodies specific for CD38, CD27, CD86, CD95, TLR-9, and IgD. The effect of adefovir treatment on B cell subsets in HBV patients was determined. The values of clinical parameters in the patients were also measured. RESULTS: The frequency of CD86+ B cells was not significantly different in chronic HBV patients but was higher in HCV patients compared with that in healthy controls. CD95 and IgD levels were lower in HBV and HCV patients than in healthy controls. A significant negative correlation occurred between the proportion of CD95+ B cells and HBV DNA viral load. The frequency of TLR-9 on the B cells in HBV and HCV patients was higher compared with that of healthy controls. After treatment with adefovir, the frequency of CD95 and IgD expressed on B cells was increased in HBV patients. CONCLUSIONS: Activated B cells and exhausted B cells homeostasis were commonly disturbed in HBV and HCV patients.


Assuntos
Antígeno B7-2/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Receptor Toll-Like 9/sangue , Receptor fas/sangue , Adenina/análogos & derivados , Adenina/uso terapêutico , Adulto , Idoso , Anticorpos Monoclonais/química , Antivirais/uso terapêutico , Linfócitos B/virologia , DNA Viral/sangue , Feminino , Citometria de Fluxo , Genótipo , Homeostase , Humanos , Imunoglobulina D/sangue , Leucócitos Mononucleares/citologia , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/química , Organofosfonatos/uso terapêutico , Fenótipo , Prevalência , Carga Viral , Adulto Jovem
9.
J Oral Pathol Med ; 43(10): 798-800, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24935264

RESUMO

This study reports a novel identical complex disease allele harboring two non-synonymous mutations that were identified in two southern Chinese individuals of the same family with cleidocranial dysplasia (CCD). Blood samples were obtained from the proband, his parents, plus 100 matched control subjects. Exons 0 to 7 of the RUNX2 gene were amplified using specific primers and sequenced. Multiple sequence alignment and protein structure modeling was performed using ClustalW2 and MODBASE software while PolyPhen-2 and MutationTaster applications were employed to predict the disease-causing potential of the identified mutations. A complex disease allele in two affected individuals harboring two non-synonymous mutations in a cis-position on exons 4 (D273N) and 5 (P299L) were identified. The identified mutations were in the conserved region and changed the protein structure.


Assuntos
Alelos , Displasia Cleidocraniana/genética , Mutação de Sentido Incorreto/genética , Adenina , Sequência de Aminoácidos/genética , Asparagina/genética , Ácido Aspártico/genética , Estudos de Casos e Controles , Sequência Conservada/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Citosina , Éxons/genética , Feminino , Guanina , Humanos , Leucina/genética , Masculino , Prolina/genética , Conformação Proteica , Timina , Dente Supranumerário/genética
10.
Front Genet ; 15: 1399810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38798699

RESUMO

Increasing research findings suggest that circular RNA (circRNA) exerts a crucial function in the pathogenesis of complex human diseases by binding to miRNA. Identifying their potential interactions is of paramount importance for the diagnosis and treatment of diseases. However, long cycles, small scales, and time-consuming processes characterize previous biological wet experiments. Consequently, the use of an efficient computational model to forecast the interactions between circRNA and miRNA is gradually becoming mainstream. In this study, we present a new prediction model named BJLD-CMI. The model extracts circRNA sequence features and miRNA sequence features by applying Jaccard and Bert's method and organically integrates them to obtain CMI attribute features, and then uses the graph embedding method Line to extract CMI behavioral features based on the known circRNA-miRNA correlation graph information. And then we predict the potential circRNA-miRNA interactions by fusing the multi-angle feature information such as attribute and behavior through Autoencoder in Autoencoder Networks. BJLD-CMI attained 94.95% and 90.69% of the area under the ROC curve on the CMI-9589 and CMI-9905 datasets. When compared with existing models, the results indicate that BJLD-CMI exhibits the best overall competence. During the case study experiment, we conducted a PubMed literature search to confirm that out of the top 10 predicted CMIs, seven pairs did indeed exist. These results suggest that BJLD-CMI is an effective method for predicting interactions between circRNAs and miRNAs. It provides a valuable candidate for biological wet experiments and can reduce the burden of researchers.

11.
Clin Exp Pharmacol Physiol ; 40(3): 190-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23278368

RESUMO

The aim of the present study was to investigate the natural killer (NK) cell phenotype and function in chronic hepatitis B virus (HBV) patients and to study the effects of entecavir therapy (10 mg/day, p.o.) on these responses. Peripheral blood NK cells were collected from 18 chronic HBV patients and 14 healthy controls. The effect of entecavir therapy on the phenotype and function of NK cells in chronic HBV patients was characterized by flow cytometry analysis. Concentrations of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), HBV viral loads in both groups and potential associations between the frequency of peripheral NK cell subsets and clinical measures were determined. There was a significant reduction in the number of CD3(-)CD56(+) NK cells in chronic HBV patients compared with healthy controls. Furthermore, there were significant increases in the percentage of CD3(-)CD56(+)NKG2D(+) and CD3(-)CD56(+)NKP30(+) NK activating receptors in chronic HBV patients compared with healthy individuals, who exhibited downregulated expression following entecavir treatment. Spearman's correlation analysis revealed that there was a significant positive correlation between the percentage of NKG2D(+) and NKP30(+) NK cells and serum ALT levels. Characterization of NK cell degranulation indicated that the frequency of CD107a(+) NK cells in HBV patients (in response to K562 stimulation) was significantly greater than in healthy controls but decreased following entecavir treatment. Entecavir treatment of hepatitis B e antigen-positive chronic HBV-infected patients not only led to a reduction in HBV DNA loads and normalization of ALT and AST levels, but also resulted in the recovery of NK cell-mediated immunity.


Assuntos
Antivirais/uso terapêutico , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Imunidade Celular/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Receptores de Células Matadoras Naturais/biossíntese , Adulto , Antivirais/administração & dosagem , Complexo CD3/biossíntese , Antígeno CD56/biossíntese , Regulação para Baixo , Feminino , Citometria de Fluxo , Guanina/administração & dosagem , Guanina/uso terapêutico , Anticorpos Anti-Hepatite B/sangue , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/biossíntese , Receptor 3 Desencadeador da Citotoxicidade Natural/biossíntese , Resultado do Tratamento , Carga Viral , Adulto Jovem
12.
Ann Hepatol ; 12(4): 539-47, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23813131

RESUMO

BACKGROUND: During the early phases of a hepatitis C virus (HCV) infection, NK cell activation appears to be critical to the induction of adaptive immune responses that have the potential of clearing the infection. This study aimed to investigate the phenotype and function of NK cells in chronic HCV (CHC) patients, particularly patients who cleared HCV infections spontaneously (SR-HCV). MATERIAL AND METHODS: Peripheral blood NK cells were compared between 36 CHC patients, 12 SR-HCV patients, and 14 healthy controls (HC). The phenotype and function of NK cells were characterized by flow cytometry. In addition, the potential associations between the frequency of NK cell subsets and ALT, AST and HCV viral loads were also analyzed. RESULTS: Our data revealed that the population of CD3-CD56+ NK cells was significantly decreased in CHC and SR-HCV patients compared to levels in HC (P = 0.031, P = 0.014). Interestingly, we found that the levels of the CD158b inhibitory receptor were higher in CHC patients compared to levels observed in HCand SR-HCV subjects (P = 0.018, P = 0.036). In addition, the percentages of the activation receptors NKp30 and NKp46 were significantly decreased in CHC and SR-HCV patients compared to their expression levels in HC (P < 0.05). Moreover, the frequencies of inducible CD107a (but not IFN-γ-secreting) NK cellsfrom both CHC and SR-HCV patients were significantly lower than frequencies observed in controls (P = 0.018, P = 0.027). CONCLUSION: Our data indicated that the higher frequency of inhibitory NK cells combined with fewer activated NK cells may be associated with HCV-related chronic inflammation involved in CHC pathogenesis.


Assuntos
Imunidade Adaptativa , Hepatite C Crônica/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Receptores KIR2DL3/sangue , Adulto , Idoso , Alanina Transaminase/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico , Humanos , Imunofenotipagem/métodos , Células Matadoras Naturais/virologia , Contagem de Linfócitos , Proteínas de Membrana Lisossomal/sangue , Masculino , Pessoa de Meia-Idade , Receptor 1 Desencadeador da Citotoxicidade Natural/sangue , Receptor 3 Desencadeador da Citotoxicidade Natural/sangue , Fenótipo , Adulto Jovem
13.
Biomed Chromatogr ; 27(11): 1547-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23760922

RESUMO

A simple method for accurate determination of nitrite and nitrate in serum was proposed to avoid the variation of nitrate reduction. For nitrite determination, serum samples were directly precipitated with methanol pre-nitrate conversion, and then the supernatant reacted with 2,3-diaminonaphthalene (DAN) to form 2,3-naphthotriazole (NAT), which was quantitatively analyzed by high-performance liquid chromatography coupled with fluorescence detection (HPLC-FL). For nitrate determination, samples were firstly heated at 70°C for 10 min to inactivate endogenous reductase-inhibiting proteins, then nitrate in the samples was quantitatively reduced to nitrite by reductase added experimentally. The difference in total nitrite concentrations between pre- and post-nitrate conversion was used to calculate the amount of nitrate in the samples. In addition to good specificity, high sensitivity, satisfactory accuracy and reproducibility, our method is simple and suitable for the quantitative determination of nanomolar level of nitrite and nitrate in a large number of serum samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Nitratos/sangue , Nitritos/sangue , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
15.
Mil Med Res ; 10(1): 35, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525300

RESUMO

BACKGROUND: Most bone-related injuries to grassroots troops are caused by training or accidental injuries. To establish preventive measures to reduce all kinds of trauma and improve the combat effectiveness of grassroots troops, it is imperative to develop new strategies and scaffolds to promote bone regeneration. METHODS: In this study, a porous piezoelectric hydrogel bone scaffold was fabricated by incorporating polydopamine (PDA)-modified ceramic hydroxyapatite (PDA-hydroxyapatite, PHA) and PDA-modified barium titanate (PDA-BaTiO3, PBT) nanoparticles into a chitosan/gelatin (Cs/Gel) matrix. The physical and chemical properties of the Cs/Gel/PHA scaffold with 0-10 wt% PBT were analyzed. Cell and animal experiments were performed to characterize the immunomodulatory, angiogenic, and osteogenic capabilities of the piezoelectric hydrogel scaffold in vitro and in vivo. RESULTS: The incorporation of BaTiO3 into the scaffold improved its mechanical properties and increased self-generated electricity. Due to their endogenous piezoelectric stimulation and bioactive constituents, the as-prepared Cs/Gel/PHA/PBT hydrogels exhibited cytocompatibility as well as immunomodulatory, angiogenic, and osteogenic capabilities; they not only effectively induced macrophage polarization to M2 phenotype but also promoted the migration, tube formation, and angiogenic differentiation of human umbilical vein endothelial cells (HUVECs) and facilitated the migration, osteo-differentiation, and extracellular matrix (ECM) mineralization of MC3T3-E1 cells. The in vivo evaluations showed that these piezoelectric hydrogels with versatile capabilities significantly facilitated new bone formation in a rat large-sized cranial injury model. The underlying molecular mechanism can be partly attributed to the immunomodulation of the Cs/Gel/PHA/PBT hydrogels as shown via transcriptome sequencing analysis, and the PI3K/Akt signaling axis plays an important role in regulating macrophage M2 polarization. CONCLUSION: The piezoelectric Cs/Gel/PHA/PBT hydrogels developed here with favorable immunomodulation, angiogenesis, and osteogenesis functions may be used as a substitute in periosteum injuries, thereby offering the novel strategy of applying piezoelectric stimulation in bone tissue engineering for the enhancement of combat effectiveness in grassroots troops.


Assuntos
Quitosana , Medicina Militar , Ratos , Humanos , Animais , Osteogênese , Engenharia Tecidual , Hidrogéis/química , Hidrogéis/farmacologia , Fosfatidilinositol 3-Quinases/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Quitosana/farmacologia , Células Endoteliais da Veia Umbilical Humana , Hidroxiapatitas/farmacologia
16.
Biochemistry ; 51(49): 9911-21, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23150986

RESUMO

Crystal (Cry) proteins are globally used in agriculture as proteinaceous insecticides. They have also been recently recognized to have great potential as anthelmintic agents in targeting parasitic roundworms (e.g., hookworms). The most extensively characterized of the anthelmintic Cry proteins is Cry5B. We report here the 2.3 Å resolution structure of the proteolytically activated form of Cry5B. This structure, which is the first for a nematicidal Cry protein, shows the familiar three-domain arrangement seen in insecticidal Cry proteins. However, domain II is unusual in that it more closely resembles a banana lectin than it does other Cry proteins. This result is consistent with the fact that the receptor for Cry5B consists of a set of invertebrate-specific glycans (attached to lipids) and also suggests that domain II is important for receptor binding. We found that not only galactose but also N-acetylgalactosamine (GalNAc) is an efficient competitor for binding between Cry5B and glycolipids. GalNAc is one of the core arthroseries tetrasaccharides of the Cry5B receptor and galactose an antennary sugar that emanates from this core. These and prior data suggest that the minimal binding determinant for Cry5B consists of a core GalNAc and two antennary galactoses. Lastly, the protoxin form of Cry5B was found to bind nematode glycolipids with a specificity equal to that of activated Cry5B, but with lower affinity. This suggests that the initial binding of Cry5B protoxin to glycolipids can be stabilized at the nematode cell surface by proteolysis. These results lay the groundwork for the design of effective Cry5B-based anthelmintics.


Assuntos
Proteínas de Bactérias/química , Endotoxinas/química , Glicolipídeos/metabolismo , Proteínas Hemolisinas/química , Nematoides/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/farmacologia , Cristalização , Endotoxinas/metabolismo , Endotoxinas/farmacologia , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Ligação Proteica , Homologia de Sequência de Aminoácidos
17.
Mol Immunol ; 143: 122-134, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35131593

RESUMO

The nucleotide oligomerization domain (NOD)-like receptor (NLR) is a relatively conserved receptor family involved in natural immunity that plays a key role in the resistance to pathogen invasion and regulation of the innate immune response. Lethenteron reissneri (lamprey) is a representative species of existing ancient jawless vertebrates. Studies of the evolutionary relationship of immune system-related molecules in lampreys can provide an important reference for the origin and evolution of innate immunity. However, the characterization and evolutionary patterns of the NLR family remain unclear in the lamprey genome. Based on the genome database of L. reissneri, we identified nine NLR genes, characterized their functional domains and chromosomal positions, and constructed a network comprising the results of gene structure and gene-collinearity analyses. Comparative genomics studies suggest that Lr-NODa and Lr-NODb most likely share the common ancestor of NOD1 and NOD2 in jawed vertebrates, and that Lr-NODb may have been generated by lamprey-specific tandem duplication of Lr-NODa. Additionally, phylogenetic analysis of the NLRC subfamily suggests that Lr-NLRC3a has ancestral traits and may be derived from the common ancestor of another vertebrate NLRC subfamily. Further analysis of the formation of the NLRC subfamily has shown that exon shuffling, domain recombination, and chromosome rearrangement play important roles in its structural evolution. Furthermore, real-time quantitative polymerase chain reaction shows that most NLR genes in lamprey are highly expressed in the immune tissues of the heart, gill, and supraneural body, with these genes also showing significant responses to polyinosinic-polycytidylic acid infection. These results indicate that NLR genes are involved in the immune protection of L. reissneri and provide an important theoretical foundation for studies of the functional evolution of vertebrate NLRs involved in the innate immune system.


Assuntos
Regulação da Expressão Gênica , Genoma , Lampreias/genética , Lipopolissacarídeos/farmacologia , Proteínas NLR/genética , Poli I-C/farmacologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Éxons/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade , Íntrons/genética , Proteínas NLR/química , Proteínas NLR/metabolismo , Filogenia , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sintenia/genética , Distribuição Tecidual
18.
J Pharm Pharmacol ; 74(1): 139-146, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34355768

RESUMO

BACKGROUND: Xanthomicrol is one of the methoxylated flavones and a promising cancer chemopreventive agent, but its anti-migration and anti-invasion ability on human hepatocellular carcinoma (HCC) remains unknown. OBJECTIVES: This study aims to explore Xanthomicrol's effects on migration and invasion ability of the human HCC Huh7 cell line. METHODS: Viability of Huh7 cells was measured by cell counting kit-8 (CCK8) assay. Cell apoptosis was assayed with flow cytometry analysis. The ability of migration and invasion of Huh7 cells was then detected through Transwell assays. Epithelial-mesenchymal transition (EMT)-related proteins were also detected through Western blot. KEY FINDINGS: Xanthomicrol inhibits the migration and invasion of Huh7 cells. The overexpression of Μu-opioid receptor (MOR) increases Huh7 cells' proliferation and enhances migration and invasion ability, while xanthomicrol treatment decreases the expression of MOR. Moreover, xanthomicrol can reverse migration, invasion and EMT-related protein expression by overexpressed MOR. CONCLUSIONS: These results suggest that xanthomicrol is a potential MOR antagonist, and it possesses potent anti-migration and anti-invasion ability on Huh7 cells.


Assuntos
Carcinoma Hepatocelular , Movimento Celular/efeitos dos fármacos , Flavonas/farmacologia , Neoplasias Hepáticas , Invasividade Neoplásica/prevenção & controle , Receptores Opioides mu/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia
19.
Mol Ecol Resour ; 21(2): 448-463, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33053263

RESUMO

The reissner lamprey Lethenteron reissneri, belonging to the class Cyclostomata, serves as a bridge between invertebrates and jawed vertebrates, and is considered the sister group of jawed vertebrates. However, despite this evolutionary significance, the genetic mechanisms underlying the adaptive evolution of the lamprey lineage remain unclear. Here, we assembled a 1.06 Gb chromosome-level draft genome of L. reissneri, with 72 chromosomes (ranging in length from 4.5 Mb to 25.9 Mb) and a scaffold N50 length of 13.23 Mb. Genome quality comparisons revealed that the reissner lamprey genome has higher completeness and contiguity than the previously published sea lamprey and Japanese lamprey genomes. Moreover, reissner lamprey, sea lamprey, and Japanese lamprey species share similar transposable element profiles and Hox gene cluster compositions, suggesting that a burst of transposable element activity and whole genome duplication occurred before their divergence. Additionally, the Lip gene copy numbers, which have been studied for their functions in the host defence system, were found to be expanded uniquely in lamprey lineages, suggesting key roles for these genes in lamprey evolution and adaptation. We also identified two neural-related genes, Nrn1 and Unc13a, with copy number expansions in jawed vertebrates, which may be functionally relevant to the origin of lamprey brains. Hence, this study not only provides the first chromosome-level reference genome for Cyclostomata, but also highlights features of the unique biology and adaptive evolution of the lamprey lineage.


Assuntos
Evolução Molecular , Lampreias , Animais , Cromossomos/genética , Genoma , Lampreias/genética , Filogenia
20.
Neural Regen Res ; 15(6): 1058-1065, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31823885

RESUMO

Oxidative stress contributes to the pathogenesis of neurodegenerative diseases. With the aim to find reagents that reduce oxidative stress, a phage display library was screened for peptides mimicking α2,6-sialyllactose (6'-SL), which is known to beneficially influence neural functions. Using Sambucus nigra lectin, which specifically binds to 6'-SL, we screened a phage display library and found a peptide comprising identical sequences of 12 amino acids. Mimetic peptide, reverse peptide and scrambled peptide were tested for inhibition of 6'-SL binding to the lectin. Indeed, lectin binding to 6'-SL was inhibited by the most frequently identified mimetic peptide, but not by the reverse or scrambled peptides, showing that this peptide mimics 6'-SL. Functionally, mimetic peptide, but not the reverse or scrambled peptides, increased viability and expression of neural cell adhesion molecule L1 in SK-N-SH human neuroblastoma cells, and promoted survival and neurite outgrowth of cultured mouse cerebellar granule neurons challenged by H2O2-induced oxidative stress. The combined results indicate that the 6'-SL mimetic peptide promotes neuronal survival and neuritogenesis, thus raising hopes for the treatment of neurodegenerative diseases. This study was approved by the Medical Ethics Committee of Shantou University Medical College, China (approval No. SUMC 2014-004) on February 20, 2014.

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