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1.
Materials (Basel) ; 16(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37241449

RESUMO

The dual-phase lattice structure composed of the matrix phase (MP) and the reinforcement phase (RP) is a novel hybrid lattice showing excellent energy absorption ability. However, the mechanical behavior of the dual-phase lattice structure under dynamic compression and the enhancement mechanism of the reinforcement phase have not been widely studied with the increase in compression speed. Based on the design requirements of dual-phase lattice materials, this paper combined octet-truss cell structures with different porosities, and the dual-density hybrid lattice specimens were fabricated via the fused deposition modeling technique. Under quasi-static and dynamic compressive loadings, the stress-strain behavior, energy absorption capacity, and deformation mechanism of the dual-density hybrid lattice structure were studied. The results showed that the quasi-static-specific energy absorption of the dual-density hybrid lattice structure was significantly higher than that of the single-density Octet lattice, and with the increase in compression strain rate, the effective specific energy absorption of the dual-density hybrid lattice structure also increased. The deformation mechanism of the dual-density hybrid lattice was also analyzed, and the deformation mode changed from an inclined deformation band to a horizontal deformation band when the strain rate changed from 10-3 s-1 to 100 s-1.

2.
Bioorg Chem ; 129: 106185, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36240541

RESUMO

The evolving SARS-CoV-2 epidemic buffets the world, and the concerted efforts are needed to explore effective drugs. Mpro is an intriguing antiviral target for interfering with viral RNA replication and transcription. In order to get potential anti-SARS-CoV-2 agents, we established an enzymatic assay using a fluorogenic substrate to screen the inhibitors of Mpro. Fortunately, Acriflavine (ACF) and Proflavine Hemisulfate (PRF) with the same acridine scaffold were picked out for their good inhibitory activity against Mpro with IC50 of 5.60 ± 0.29 µM and 2.07 ± 0.01 µM, respectively. Further evaluation of MST assay and enzymatic kinetics experiment in vitro showed that they had a certain affinity to SARS-CoV-2 Mpro and were both non-competitive inhibitors. In addition, they inhibited about 90 % HCoV-OC43 replication in BHK-21 cells at 1 µM. Both compounds showed nano-molar activities against SARS-CoV-2 virus, which were superior to GC376 for anti-HCoV-43, and equivalent to the standard molecule remdesivir. Our study demonstrated that ACF and PRF were inhibitors of Mpro, and ACF has been previously reported as a PLpro inhibitor. Taken together, ACF and PRF might be dual-targeted inhibitors to provide protection against infections of coronaviruses.


Assuntos
Acriflavina , Tratamento Farmacológico da COVID-19 , Proteases 3C de Coronavírus , Inibidores de Cisteína Proteinase , Proflavina , SARS-CoV-2 , Inibidores de Protease Viral , Acriflavina/farmacologia , Proflavina/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Protease Viral/farmacologia , Mesocricetus , Animais , Cricetinae , Linhagem Celular , Replicação Viral/efeitos dos fármacos
3.
Drug Metab Dispos ; 50(7): 931-941, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35512804

RESUMO

Futibatinib (FUT) is a potent inhibitor of fibroblast growth factor receptor (FGFR) 1-4 that is currently under clinical investigation for intrahepatic cholangiocarcinoma. Unlike its predecessors, FUT possesses an acrylamide warhead, which enables it to bind covalently to a free cysteine residue in the FGFR kinase domain. However, it remains uninterrogated if this electrophilic α, ß -unsaturated carbonyl scaffold could also directly or indirectly engender off-target covalent binding to nucleophilic centers on other cellular proteins. Here, we discovered that FUT inactivated both CYP3A isoforms with inactivator concentration at half-maximum inactivation rate constant, maximum inactivation rate constant, and partition ratios of 12.5 and 51.4 µ M, 0.25 and 0.06 minutes-1, and ∼52 and ∼58 for CYP3A4 and CYP3A5, respectively. Along with its time-, concentration-, and cofactor-dependent inhibitory profiles, FUT also exhibited several cardinal features that were consistent with mechanism-based inactivation. Moreover, the nature of inactivation was unlikely to be pseudo-irreversible and instead arose from the covalent modification of the cytochrome P450 apoprotein and/or its heme moiety due to the lack of substantial enzyme activity recovery following dialysis and chemical oxidation, as well as the absence of the diagnostic Soret peak in spectral analyses. Finally, utilizing glutathione (GSH) trapping and high-resolution mass spectrometry, we illuminated that while the acrylamide moiety in FUT could nonenzymatically conjugate to GSH via Michael addition, it was not implicated in the covalent inactivation of CYP3A. Rather, we surmised that it likely stemmed from the metabolic activation of its acrylamide covalent warhead to a highly electrophilic epoxide intermediate that could covalently modify CYP3A and culminate in its catalytic inactivation. SIGNIFICANCE STATEMENT: In this study, we reported for the first time the inactivation of CYP3A by futibatinib (FUT). Furthermore, using FUT as an exemplary targeted covalent inhibitor, our study revealed the propensity for its acrylamide Michael acceptor moiety to be metabolically activated to a highly electrophilic epoxide. Due to the growing resurgence of covalent inhibitors and the well-established toxicological ramifications associated with epoxides, we advocate that closer scrutiny be adopted when profiling the reactive metabolites of compounds possessing an α, ß -unsaturated carbonyl scaffold.


Assuntos
Citocromo P-450 CYP3A , Compostos de Epóxi , Acrilamida , Ativação Metabólica , Citocromo P-450 CYP3A/metabolismo , Pirazóis , Pirimidinas , Pirróis , Diálise Renal
4.
J Pharmacol Exp Ther ; 382(2): 123-134, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35640957

RESUMO

Infigratinib (INF) is a fibroblast growth factor receptor inhibitor that was recently United States Food and Drug Administration-approved for the treatment of advanced or metastatic cholangiocarcinoma. We previously established that INF inhibited and inactivated cytochrome P450 3A4 (CYP3A4). Here, in a follow up to our previous study, we identified for the first time that INF also elicited potent competitive inhibition and mechanism-based inactivation of CYP2J2 with kinetic parameters K i, K I, k inact, and a partition ratio of 1.94 µM, 0.10 µM, 0.026 minute-1, and ∼3, respectively, when rivaroxaban was harnessed as the probe substrate. Inactivation was revealed to exhibit cofactor-dependency and was attenuated by an alternative substrate (astemizole) and direct inhibitor (nilotinib) of CYP2J2. Additionally, the nature of inactivation was unlikely to be pseudo-irreversible and instead arose from covalent modification due to the lack of substantial enzyme activity recovery after dialysis and chemical oxidation, as well as the lack of a resolvable Soret band in spectral scans. Glutathione trapping confirmed that the identity of the putative reactive intermediate implicated in the covalent inactivation of both CYP2J2 and CYP3A4 was identical and likely attributable to an electrophilic p-benzoquinonediimine intermediate of INF. Finally, mechanistic static modeling revealed that by integrating the previously arcane inhibition and inactivation kinetic parameters of CYP2J2-mediated rivaroxaban hydroxylation by INF illuminated in this work, together with those previously documented for CYP3A4, a 49% increase in the systemic exposure of rivaroxaban was projected. Our modeling results predicted a potential risk of metabolic drug-drug interactions between the clinically relevant combination of rivaroxaban and INF in the setting of cancer. SIGNIFICANCE STATEMENT: This study reported that INF elicits potent reversible inhibition and mechanism-based inactivation of CYP2J2. Furthermore, static modelling predicted that its coadministration with the direct oral anticoagulant rivaroxaban may potentially culminate in a metabolic drug-drug interaction (DDI) leading to an increased risk of major bleeding. As rivaroxaban is steadily gaining prominence as the anticoagulant of choice in the treatment of cancer-associated venous thromboembolism, the DDI projections reported here are clinically relevant and warrant further investigation via physiologically based pharmacokinetic modelling and simulation.


Assuntos
Citocromo P-450 CYP3A , Rivaroxabana , Anticoagulantes , Citocromo P-450 CYP2J2 , Citocromo P-450 CYP3A/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas , Compostos de Fenilureia , Pirimidinas , Rivaroxabana/farmacocinética
5.
Small ; 18(23): e2200133, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35445535

RESUMO

Refrigeration based on the electrocaloric effect can offer many advantages over conventional cooling technologies in terms of efficiency, size, weight, and power source. The discovery of ferroelectric and antiferroelectric properties in fluorite-based materials in 2011 has led to diverse applications related to memory (e.g., ferroelectric tunnel junctions, nonvolatile memory, and field-effect transistors) and energy fields (e.g., energy storage and harvesting, electrocaloric refrigeration, and infrared detection). Fluorite-based materials exhibit several properties not shared by most conventional materials (such as in terms of compatibility with complementary metal-oxide semiconductors and 3D nanostructures, deposition thickness at the nanometer scale, and simple composition). Here, the electrocaloric refrigeration properties of fluorite-based ferroelectric/antiferroelectric materials are reviewed by focusing on the advantages of ZrO2 - and HfO2 -based materials (e.g., relative to conventional perovskite- and polymer-based counterparts). Finally, the recent progress made in this research field are also discussed along with its future perspectives.

6.
Chem Eng J ; 441: 136043, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35370448

RESUMO

Disposable surgical masks are widely used by the general public since the onset of the coronavirus outbreak in 2019. However, current surgical masks cannot self-sterilize for reuse or recycling for other purposes, resulting in high economic and environmental costs. To solve these issue, herein we report a novel low-cost surgical mask decorated with copper sulfide (Cu2-xS) nanocrystals for photothermal sterilization in a short time (6 min). With the spun-bonded nonwoven fabrics (SNF) layer from surgical masks as the substrate, Cu2-xS nanocrystals are in-situ grown on their surface with the help of a commercial textile adhesion promoter. The SNF-Cu2-xS layer possesses good hydrophobicity and strong near infrared absorption. Under the irradiation with an infrared baking lamp (IR lamp, 50 mW cm-2), the surface temperature of SNF-Cu2-xS layer on masks can quickly increase to over 78 °C, resulting from the high photothermal effects of Cu2-xS nanocrystals. As a result, the polluted masks exhibit an outstanding antibacterial rate of 99.9999% and 85.4% for the Escherichia coli (E.coli) and Staphylococcus aureus (S. aureus) as well as the inactivation of human coronavirus OC43 (3.18-log10 decay) and influenza A virus A/PR/8/34 (H1N1) (3.93-log10 decay) after 6 min irradiation, and achieve rapid sterilization for reuse and recycling. Therefore, such Cu2-xS-modified masks with IR lamp-driven antibacterial and antiviral activity have great potential for real-time personal protection.

7.
Microbiol Spectr ; 9(3): e0109421, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34756078

RESUMO

BK polyomavirus (BKPyV) is a small double-stranded DNA virus and ubiquitous human pathogen that particularly affects immunocompromised individuals. Antiviral therapy for BKPyV is urgently needed. Intracellular irons have an important role in many viral infections, yet its contribution to BKPyV and replication has not been explored. In this study, we explored the interaction between BKPyV infection and intracellular iron and the inhibitory effect of iron depletion on BKPyV infection. By creating a low-intracellular-iron environment, we demonstrated that the iron-chelating-induced iron depletion inhibits BKPyV infection in primary renal tubular epithelial cells (RPTECs) and urinary bladder cancer cells (TCCSUP cells). Iron depletion exerts an inhibitory effect after BKPyV enters the nucleus, which might be due to the inhibition of the protein synthesis of exogenous genes in iron-depleted cells. Further exploration of the target proteins of iron-regulating viral infection could potentially be used to develop new strategies for urgently needed anti-BKPyV therapies. IMPORTANCE BKPyV poses a serious threat to the health of immunocompromised patients, and there are currently no curative drugs. Understanding the relationship between the virus and intracellular environment contributes to the discovery of antiviral targets. We demonstrate here that BKPyV is inhibited in cells with a low-iron environment. We also find that iron-chelating-induced iron depletion inhibits viral and exogenous protein synthesis. Further exploration of the target proteins of iron regulation could have great potential in developing new drugs against BKPyV and other viruses.


Assuntos
Antivirais/farmacologia , Vírus BK/metabolismo , Quelantes de Ferro/farmacologia , Ferro/análise , Infecções por Polyomavirus/tratamento farmacológico , Biossíntese de Proteínas/efeitos dos fármacos , Vírus BK/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Deficiências de Ferro/induzido quimicamente , Replicação Viral/efeitos dos fármacos
8.
Transpl Int ; 34(11): 2087-2097, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34309081

RESUMO

The application of perfluorocarbons, which can carry large quantities of oxygen, in organ preservation was limited by their poor solubility in water. A stable form of perfluorocarbon dispersed in suitable buffers is urgently needed. Perfluorocarbon emulsion was designed and characterized with respect to size distribution, rheology, stability, and oxygen-carrying capacity. The state of DCD rat donor livers preserved by the oxygenated perfluorocarbon emulsion was studied after ex vivo reperfusion by using biochemistry, pathology, and immunohistochemistry methods. Perfluorocarbon emulsion was successfully prepared by high-pressure homogenization. Optimized perfluorocarbon emulsion showed nanoscale size distribution, good stability, and higher oxygen loading capacity than that of HTK solution or water. The state of preserved livers after cardiac death rat liver was improved significantly after static cold storage for 48 hours in this oxygenated perfluorocarbon emulsion. The ATP content and down-regulation of HIF-1a expression after preservation of the liver graft by the oxygenated perfluorocarbon emulsion suggested the advantage of adequate oxygen supply for adequate time. This perfluorocarbon emulsion reported here might be considered a promising system for oxygenated donor liver storage by attenuation of hypoxia.


Assuntos
Fluorocarbonos , Transplante de Fígado , Soluções para Preservação de Órgãos , Animais , Emulsões , Humanos , Fígado , Doadores Vivos , Masculino , Preservação de Órgãos , Perfusão , Ratos , Ratos Sprague-Dawley
9.
Medicine (Baltimore) ; 99(40): e22292, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019404

RESUMO

This study aims to assess the survival status of patients with Primary gallbladder cancer (PGC) and analyze the prognosis factors to facilitate the exploration of the prevention and therapeutic strategies of PGC.Data from 2433 PGC patients collected from 2010 to 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. The SEER*Stat, SPSS 23.0 and GraphPad Prism 8 were used for statistical analyses. Kaplan Meier analysis was performed for the survival curve, log-rank test analyses were used to compare the survival rate difference and Cox regression analyses were performed to determine the prognosis factors.A total of 2433 PGC cases were reported from 2010 to 2015. The median age was 64.2 ±â€Š10.4 years old and the percentages of the white patients were 73.7% (1794/2433). The percentage of patients who received surgery treatment was 82.1% (1998/2433). The overall median survival time of all patients was 19 months and the 5-year survival rate was 28.8%. The 5-year survival rate of PGC patients in pN2 stage dropped to 0% and the 5-year survival rate for PGC patients with distant metastasis was only 2.7%. Age, tumor size, grade, pT stage, pM stage were risk factors for prognosis, surgery or not and radiation or not were protective factors for prognosis.Survival analysis of PGC patients based on the SEER database have provided an opportunity for understanding PGC prognosis and the basis for the exploration of viable PGC prevention and therapeutic strategies.


Assuntos
Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Idoso , Feminino , Neoplasias da Vesícula Biliar/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Programa de SEER , Fatores Socioeconômicos , Carga Tumoral
10.
Cancer Med ; 8(15): 6614-6623, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31517445

RESUMO

BACKGROUND: The use of alpha-fetoprotein (AFP) testing for the surveillance, diagnosis, and prognosis of hepatocellular carcinoma (HCC) remains controversial. Here, we compared AFP testing rates, elevated AFP rates, factors associated with elevated AFP levels, and prognostic factors associated with overall survival (OS) in HCC patients from different ethnic groups. METHODS: Patients with HCC were identified from the Surveillance, Epidemiology, and End Results registries. Race was categorized as white, black, and others. AFP testing rates and elevated AFP rates were analyzed. Multivariable logistic regression and Cox regression analyses were used to identify independent factors associated with elevated AFP levels and prognosis, respectively. All statistical tests were two sided. RESULTS: A proportion of 79.2% of total HCC patients had AFP testing reports; 77.3% of white, 79.7% of black, and 81.2% of other races underwent AFP testing. Compared with white and other races, black HCC patients had a higher rate of elevated AFP levels among all patients and the early-stage HCC patient cohort. Elevated AFP level was a significant prognostic factor for all HCC patients in different race groups. Factors associated with elevated AFP level and prognostic factors associated with OS varied significantly by race. CONCLUSIONS: AFP testing, elevated AFP rates, predictors of elevated AFP level, and prognostic factors associated with OS differed significantly according to race after adjusting for AFP levels among the three groups. AFP testing for the surveillance, diagnosis, and prognosis of HCC patients is strongly recommended, although racial disparities need to be considered.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etnologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etnologia , Regulação para Cima , alfa-Fetoproteínas/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/metabolismo , Detecção Precoce de Câncer , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prognóstico , Programa de SEER , Taxa de Sobrevida , Estados Unidos/etnologia , Adulto Jovem
11.
J Cell Biochem ; 120(4): 5244-5255, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30302811

RESUMO

Hepatocellular carcinoma (HCC) treatments are evaluated by two-dimensional (2D) in vitro culture systems, despite their limited ability to predict drug efficacy. The three-dimensional (3D) microporous scaffold provides the possibility of generating more reliable preclinical models to increase the efficacy of cancer treatments. The physical properties of a microporous cellulosic scaffold were evaluated. The cellulosic scaffold was biocompatible and had a highly porous network with appropriate pore size, swelling rate, and stiffness of cancer cell cultures. Cellulosic scaffolds were compared with 2D polystyrene for the culture of HepG2 and Huh7 human HCC cells. Cellulosic scaffolds promoted tumor spheroid formation. Cells cultured on scaffolds were more resistant to chemotherapy drugs and showed upregulation of EpCAM and Oct4. The migration ability of HCC cells cultured on scaffolds was significantly greater than that of cells grown in 2D cultures as evidenced by the downregulation of E-cadherin. In addition, the proportion of CD44+/CD133+ HCC cancer stem cells (CSCs) was significantly greater in cells cultured on scaffolds than in those grown in 2D cultures. These findings suggest that cellulosic scaffolds effectively mimic the in vivo tumor behavior and may serve as a platform for the study of anticancer therapeutics and liver CSCs.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Antígeno AC133/genética , Antineoplásicos/farmacologia , Caderinas/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Molécula de Adesão da Célula Epitelial/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Receptores de Hialuronatos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Fator 3 de Transcrição de Octâmero/genética
12.
Cancer Manag Res ; 10: 4401-4410, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349373

RESUMO

OBJECTIVE: The effects of hepatocellular carcinoma (HCC) tumor size on clinical presentation and treatment selection and its role as a prognostic factor remain unclear. The present study is a comprehensive analysis of the clinical correlation between tumor size at diagnosis and pathological grades, clinical staging, disparities of treatment, and survival of patients with HCC. MATERIALS AND METHODS: Patients with HCC were separated into groups according to tumor size as follows: 0.1-2.0, 2.1-5.0, 5.1-10.0, and 10.1-20.0 cm. Logistic regression analysis was used to determine the relationship between tumor size at diagnosis and pathological grade, Surveillance, Epidemiology, and End Results (SEER) historic stage A, and treatment selection. The survival of HCC patients stratified by tumor size was estimated by Kaplan-Meier and 5-year survival analyses using the log-rank test. Multivariable analysis of overall survival was performed using the Cox proportional hazards model. Tumor size at diagnosis was an independent risk factor of pathological grade, and SEER historic stage A was revealed by logistic regression analysis. RESULTS: The 5-year survival rate was 21.9% vs 14.3% vs 9.2% vs 7.7% for all HCC patients and 31.2% vs 23.6% vs 20.3% vs 15.5% for patients who underwent surgery with tumor sizes of 0.1-2.0 vs 2.1-5.0 and 5.1-10.0 vs 10.1-20.0 cm, respectively; multivariable Cox regression analysis identified tumor size at diagnosis as an independent predictor of survival risk with HR of 1.00 vs 1.66 vs 2.92 vs 3.67, respectively. CONCLUSION: Tumor size at diagnosis could be used as an independent risk predictor associated with histological grade, stage, selection of surgery, and survival in HCC.

13.
Cell Physiol Biochem ; 44(4): 1651-1664, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29216638

RESUMO

BACKGROUND/AIMS: An increase in intracellular lipid droplet formation and hepatic triglyceride (TG) content usually results in nonalcoholic fatty liver disease. However, the mechanisms underlying the regulation of hepatic TG homeostasis remain unclear. METHODS: Oil red O staining and TG measurement were performed to determine the lipid content. miRNA expression was evaluated by quantitative PCR. A luciferase assay was performed to validate the regulation of Yin Yang 1 (YY1) by microRNA (miR)-122. The effects of miR-122 expression on YY1 and its mechanisms involving the farnesoid X receptor and small heterodimer partner (FXR-SHP) pathway were evaluated by quantitative PCR and Western blot analyses. RESULTS: miR-122 was downregulated in free fatty acid (FFA)-induced steatotic hepatocytes, and streptozotocin and high-fat diet (STZ-HFD) induced nonalcoholic steatohepatitis (NASH) in mice. Transfection of hepatocytes with miR-122 mimics before FFA induction inhibited lipid droplet formation and TG accumulation in vitro. These results were verified by overexpressing miR-122 in the livers of STZ-HFD-induced NASH mice. The 3'-untranslated region (3'UTR) of YY1 mRNA is predicted to contain an evolutionarily conserved miR-122 binding site. In silico searches, a luciferase reporter assay and quantitative PCR analysis confirmed that miR-122 directly bound to the YY1 3'UTR to negatively regulate YY1 mRNA in HepG2 and Huh7 cells. The (FXR-SHP) signaling axis, which is downstream of YY1, may play a key role in the mechanism of miR-122-regulated lipid homeostasis. YY1-FXR-SHP signaling, which is negatively regulated by FFA, was enhanced by miR-122 overexpression. This finding was also confirmed by overexpression of miR-122 in the livers of NASH mice. CONCLUSIONS: The present results indicate that miR-122 plays an important role in lipid (particularly TG) accumulation in the liver by reducing YY1 mRNA stability to upregulate FXR-SHP signaling.


Assuntos
Gotículas Lipídicas/metabolismo , MicroRNAs/metabolismo , Triglicerídeos/metabolismo , Fator de Transcrição YY1/metabolismo , Regiões 3' não Traduzidas , Animais , Antagomirs/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Ácidos Graxos não Esterificados/farmacologia , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Células Hep G2 , Humanos , Gotículas Lipídicas/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Alinhamento de Sequência , Fator de Transcrição YY1/química , Fator de Transcrição YY1/genética
14.
Oncol Rep ; 37(4): 2398-2404, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259917

RESUMO

In the present study, we first examined the expression of USP39 protein using tissue array containing 90 colorectal cancer (CRC) tissues and 9 clinical samples, and observed that it has significantly higher expression in cancer tissues as compared to the corresponding adjacent normal tissues. Also, we tested USP39 expression level in four CRC cancer cell lines and identified that it indeed had higher expression in all these CRC cell lines. In addition, its knockdown inhibited not only the cell growth of SW480 and HT29 cells, but also the cell migration and invasion. Further analysis of its molecular mechanism suggested that the expression of four crucial proteins of Wnt/ß-catenin pathway, including ß-catenin, TCF4, MMP2 and MMP9 was reduced as a result of USP39 knockdown. Taken together, all these findings demonstrated that USP39 protein plays an important role in the growth and metastasis of colorectal cancer mainly through Wnt/ß-catenin pathway.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteases Específicas de Ubiquitina/metabolismo , Via de Sinalização Wnt , Adulto , Idoso , Idoso de 80 Anos ou mais , Células CACO-2 , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Feminino , Células HT29 , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Análise de Sobrevida
15.
Protein Expr Purif ; 129: 162-172, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26363113

RESUMO

We have previously published a report on the cloning and characterization of Harobin, a fibrinolytic serine protease. However, the broad application of this fibrinolytic enzyme is limited by its low expression level that was achieved in Pichia pastoris. To counteract this shortcoming, random and site-directed mutagenesis have been combined in order to improve functional expression and activity of Harobin. By screening 400 clones from random mutant libraries for enhanced fibrinolytic activity, two mutants were obtained: N111R, R230G. By performing site-directed mutagenesis, a Harobin double mutant, N111R/R230G, was constructed and can be functionally expressed at higher level than the wild type enzyme. In addition, it possessed much higher fibrinolytic and amidolytic activity than the wild type enzyme and other single mutants. The N111R/R230G expressed in basal salts medium was purified by a three step purification procedure. At pH of 6.0-9.0, and the temperature range of 40-90 °C, N111R/R230G was more active and more heat resistant. The fibrinolytic activities of Harobin mutants were completely inhibited by PMSF and SBTI, but not by EDTA, EGTA, DTT, indicating that Harobin is a serine protease. N111R/R230G showed much better anti-thrombosis effect than wild type Harobin and single mutants, and could significantly increase bleeding and clotting time. Intravenous injection of N111R/R230G in spontaneous hypertensive rats (SHR) led to a significant reduction in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) (p < 0.01), while heart rate (HR) was not affected. The in vitro and in vivo results of the present study revealed that Harobin double mutant N111R/R230G is an appropriate candidate for biotechnological applications due to its high expression level and high activity in area of thrombosis and hypertension.


Assuntos
Venenos Elapídicos/genética , Elapidae/genética , Fibrinólise/efeitos dos fármacos , Fibrinolíticos , Mutagênese Sítio-Dirigida , Serina Proteases , Animais , Venenos Elapídicos/enzimologia , Elapidae/metabolismo , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/metabolismo , Fibrinolíticos/farmacologia , Humanos , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Serina Proteases/biossíntese , Serina Proteases/genética , Serina Proteases/isolamento & purificação , Serina Proteases/farmacologia
16.
Life Sci ; 133: 1-7, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25921762

RESUMO

AIMS: The effective anti-HBV drugs on the market are mainly immunomodulators or nucleoside analogs. The uses of INF-α and lamivudine (3TC) are considerably limited by their low response rate, side effects, drug resistance and HBV recurrence. Thus, new mechanism-based drugs remain in urgent need. This study aimed to investigate the anti-HBV effects of the novel compound Z060228 and to confirm its anti-HBV mechanisms. MAIN METHODS: HepG2.2.15 cells and HBV-transgenic mice were used to evaluate the anti-HBV activity of Z060228. Conformational changes of the capsid structure induced by Z060228 were detected with high-resolution electron microscopy (EM), size-exclusion chromatography (SEC), and atomic force microscopy (AFM). KEY FINDINGS: The HBV DNA replication in the supernatants of the HepG2.2.15 cells was effectively inhibited by Z060228 and Bay41-4109. In the liver of HBV-transgenic mice, the HBcAg content was significantly decreased and HBV DNA replication was also inhibited after high-dose (30 mg/kg) Z060228 treatment. Z060228 and Bay41-4109 exhibited similar effects on the self-assembly of Cp149. SEC data revealed that Z060228 altered the equilibrium (a state of stability) of Cp149 assembly. EM data further demonstrated that Z060228 could prevent Cp149 from self-assembling to the correct core particles. Additionally, AFM results showed that a low concentration of Z060228 caused Cp149 syncretizing, whereas a high concentration caused Cp149 to polymerize. SIGNIFICANCE: Z060228 was demonstrated to be a potential capsid targeting anti-HBV drug candidate. The methods employed here could be used as a general strategy to study mechanisms of self-assembling protein-targeted drugs.


Assuntos
Antivirais/química , Antivirais/uso terapêutico , Capsídeo/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Fígado/virologia , Animais , Antivirais/farmacologia , Capsídeo/metabolismo , Replicação do DNA/efeitos dos fármacos , Células Hep G2 , Hepatite B/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , Masculino , Camundongos Transgênicos , Replicação Viral/efeitos dos fármacos
17.
Zootaxa ; (3811): 185-206, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24943158

RESUMO

We here briefly review the Paranthrenini fauna of Mainland China and provide a checklist of 21 species for this region. We describe six new species: Paranthrene rubomacula Kallies & Owada sp. nov., Nokona opaca Kallies & Wang sp. nov., Nokona bractea Kallies & Arita sp. nov., Scoliokona nanlingensis Kallies & Arita sp. nov., Scoliokona spissa Kallies & Arita sp. nov., Scoliokona shimentai Kallies & Wu sp. nov. Furthermore, we provide numerous new combinations of species formerly associated with the genus Paranthrene in South East Asia, with 12 species transferred to Nokona Matsumura, 1931, 4 to Scoliokona Kallies & Arita, 1998, and one to Cyanosesia Gorbunov & Arita, 1995 (comb. nov.). The genus name Aritasesia Nakamura, 2009 (syn. nov.) is considered a junior subjective synonym of Nokona Matsumura, 1931. 


Assuntos
Mariposas/anatomia & histologia , Mariposas/classificação , Animais , China , Feminino , Masculino
18.
Antimicrob Agents Chemother ; 57(11): 5344-54, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23959305

RESUMO

Hepatitis B virus (HBV)-associated chronic liver diseases are treated with nucleoside analogs that target the virus polymerase. While these analogs are potent, drugs are needed to target other virus-encoded gene products to better block the virus replication cycle and chronic liver disease. This work further characterized GLS4 and compared it to the related BAY 41-4109, both of which trigger aberrant HBV core particle assembly, where the virus replication cycle occurs. This was done in HepAD38 cells, which replicate HBV to high levels. In vitro, GLS4 was significantly less toxic for primary human hepatocytes (P < 0.01 up to 100 µM), inhibited virus accumulation in the supernantant of HepAD38 cells (P < 0.02 up to 100 nM), inhibited HBV replicative forms in the liver with a significantly lower 50% effective concentration (EC50) (P < 0.02), and more strongly inhibited core gene expression (P < 0.001 at 100 to 200 nM) compared to BAY 41-4109. In vivo characterization was performed in nude mice inoculated with HepAD38 cells, which grew out as tumors, resulting in viremia. Treatment of mice with GLS4 and BAY 41-4109 showed strong and sustained suppression of virus DNA to about the same extents both during and after treatment. Both drugs reduced the levels of intracellular core antigen in the tumors. Alanine aminotransferase levels were normal. Tumor and total body weights were not affected by treatment. Thus, GLS4 was as potent as the prototype, BAY 41-4109, and was superior to lamivudine, in that there was little virus relapse after the end of treatment and no indication of toxicity.


Assuntos
Antivirais/farmacologia , DNA Viral/antagonistas & inibidores , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Pirimidinas/farmacologia , Tiazóis/farmacologia , Viremia/tratamento farmacológico , Vírion/efeitos dos fármacos , Animais , Antivirais/síntese química , Linhagem Celular , DNA Viral/biossíntese , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/ultraestrutura , Hepatite B Crônica/virologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Hepatócitos/virologia , Humanos , Lamivudina/farmacologia , Masculino , Camundongos , Camundongos Nus , Testes de Sensibilidade Microbiana , Cultura Primária de Células , Piridinas/farmacologia , Pirimidinas/síntese química , Tiazóis/síntese química , Proteínas do Core Viral/antagonistas & inibidores , Proteínas do Core Viral/metabolismo , Viremia/virologia , Vírion/ultraestrutura , Replicação Viral/efeitos dos fármacos
19.
BMC Cancer ; 13: 167, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23537372

RESUMO

BACKGROUND: UCN-01 (7-hydroxystaurosporine), a protein kinase inhibitor, has attracted a great deal of attention as a potent antitumour agent. Several clinical trials of UCN-01 alone or in combination with other agents for different tumour types are currently underway, and some of these trials have had positive results. Hepatocellular carcinoma has high incidence rates and is associated with poor prognosis and high mortality rates. METHODS: Three different hepatoma cell lines (Huh7, HepG2, and Hep3B) were treated with different concentrations of UCN-01, and the anti-tumour effects of UCN-01 were evaluated. Following UCN-01 treatment, cell growth was measured using an MTT assay, cell cycle arrest was assayed using flow cytometry, and the mechanisms of cell cycle arrest and invasion inhibition were investigated through western blotting and a Matrigel invasion assay. RESULTS: After a 72-h UCN-01 treatment, the growth of different hepatoma cell lines was significantly inhibited in a dose-dependent manner, with IC50 values ranging from 69.76 to 222.74 nM. Flow cytometry results suggested that UCN-01 inhibits proliferation in the hepatoma cells by inducing S and G2/M phase arrest, but not G1/S arrest, which differs from previous reports that used other tumour cell lines. Western blot results illustrated that UCN-01 induces a G2/M phase arrest, regardless of the status of the p53/P21(waf1) pathway, whereas the CHK2/CDC25C pathway and the p53/p21(waf1)pathway were involved in the UCN-01-induced S phase arrest. UCN-01 remarkably inhibited Huh7 cell invasion in a time-dependent manner. Suppression of Huh7 cell invasion may be due to the down-regulation of phosphorylated ß-catenin by UCN-01. CONCLUSIONS: These findings suggest that UCN-01 induces hepatoma cell growth inhibition by regulating the p53/p21(waf1) and CHK2/CDC25 pathways. Suppression of Huh7 cell invasion by UCN-01 may be due to the down-regulation of phosphorylated ß-catenin. These data lend support for further studies on UCN-01 as a promising anti-HCC candidate.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estaurosporina/análogos & derivados , Proteína Supressora de Tumor p53/metabolismo , Fosfatases cdc25/metabolismo , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quinase do Ponto de Checagem 2 , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Estaurosporina/farmacologia , Proteína Supressora de Tumor p53/genética
20.
Antivir Ther ; 17(5): 793-803, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22668794

RESUMO

BACKGROUND: HBV infection continues to be an important worldwide cause of morbidity and mortality. Patients with chronic hepatitis B can be successfully treated using nucleoside/nucleotide analogues. However, drug-resistant HBV mutants frequently arise, leading to treatment failure and progression to liver disease. Here, we report the effects of GLS4, a non-nucleosidic inhibitor that exhibits a novel and highly specific anti-HBV activity. METHODS: The median inhibitory concentrations (IC(50)s) of GLS4 on HBV were measured by Southern blotting. HBV capsid and core protein levels were detected by immunoblotting. To determine the antiviral activity of GLS4 against adefovir dipivoxil (ADV)-resistant HBV mutants, HepG2 cells transiently transfected with PUC-HBV1.2 plasmids that contained one of three major ADV-resistant mutations (rtA181T, rtA181V and rtN236T) were treated with GLS4. Intracellular HBV replicative intermediates were detected by Southern blotting. The effect on the in vitro assembly of HBV capsid protein was examined using dynamic light scattering and electron microscopy. RESULTS: The IC(50) of GLS4 was 0.012 µM, which is significantly lower than that of lamivudine (0.325 µM). Immunoblot analysis of HepG2.2.15 cells and transiently transfected HepG2 cells indicated that GLS4 treatment interfered with the formation of core particles (assembly). The ADV-resistant HBV mutant strains were also sensitive to GLS4. Upon examining the in vitro assembly of HBV core protein 149 by electron microscopy, increased aberrant particles were observed after GLS4 treatment. CONCLUSIONS: GLS4 is a new and unique potential anti-HBV agent that possesses a different mechanism of action than existing therapeutic drugs.


Assuntos
Adenina/análogos & derivados , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Mutação , Organofosfonatos/farmacologia , Pirimidinas/farmacologia , Tiazóis/farmacologia , Replicação Viral/efeitos dos fármacos , Adenina/farmacologia , Antivirais/química , Antivirais/toxicidade , Proteínas do Capsídeo/antagonistas & inibidores , DNA Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Células Hep G2 , Humanos , Concentração Inibidora 50 , Proteínas do Core Viral/antagonistas & inibidores , Montagem de Vírus/efeitos dos fármacos
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