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1.
Small ; 19(23): e2207675, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36897005

RESUMO

The poor oxygen diffusion and sluggish oxygen reduction reaction (ORR) kinetics at multiphase interfaces in the cathode suppress the practical application of zinc-air batteries. Developing effective strategies to tackle the issue is of great significance for overcoming the performance bottleneck but remains challenging. Here, a multiscale hydrophobic surface is designed on the iron single-atom catalyst via a gas-phase fluorination-assisted method inspired by the structure of gas-trapping mastoids on lotus leaves. The hydrophobic Fe-FNC attains a higher peak power density of up to 226 mW cm-2 , a long durability of up close to 140 h, and better cyclic durability of up to 300 cycles compared to the corresponding Pt/C-based Zn-air battery. Experiments and theoretical calculations indicate that the formed more triple-phase interfaces and exposed isolated Fe-N4 sites are proposed as the governing factors in boosting electrocatalytic ORR activity and remarkable cycling durability for Zn-air batteries.

2.
J Transl Med ; 21(1): 453, 2023 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422632

RESUMO

BACKGROUND: USP51 is a deubiquitinase (DUB), that is involved in diverse cellular processes. Accumulating evidence has demonstrated that USP51 contributes to cancer development. However, its impact on non-small cell lung carcinoma (NSCLC) cell malignancy is largely unknown. METHODS: In this study, we performed bioinformatics analysis on a dataset from The Cancer Genome Atlas to determine the association between USP51 and cell stemness marker expression in NSCLC patients. RT‒qPCR, Western blotting, and flow cytometry were performed to examine the effects of USP51 depletion on stemness marker expression. Colony formation and tumor sphere formation assays were used to assess the stemness of NSCLC cells. A cycloheximide chase time-course assay and a polyubiquitination assay were carried out to analyze the effects of USP51 on the TWIST1 protein level. TWIST1 was overexpressed in USP51 knockdown NSCLC cells to determine whether TWIST1 is required. The effect of USP51 on the in vivo growth of NSCLC cells was tested through subcutaneous injections in mice. RESULTS: We found that USP51 deubiquitinates TWIST1, which is significantly upregulated in the tissues of patients with NSCLC and is closely associated with poor prognosis. USP51 expression was positively correlated with the expression of stemness marker CD44, SOX2, NANOG, and OCT4 in NSCLC patients. USP51 depletion attenuated mRNA, protein, and cell surface expression of stemness markers and the stemness of NSCLC cells. Ectopic USP51 expression potentiated the stability of the TWIST1 protein by attenuating its polyubiquitination. In addition, TWIST1 re-expression in NSCLC cells reversed the inhibitory effect of USP51 knockdown on cell stemness. Furthermore, the in vivo results confirmed the suppressive effect of USP51 depletion on NSCLC cell growth. CONCLUSIONS: Our results show that USP51 maintains the stemness of NSCLC cells by deubiquitinating TWIST1. Knocking it down reduces both cell stemness and growth of NSCLC cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteína 1 Relacionada a Twist , Proteases Específicas de Ubiquitina , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo , Humanos , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo
3.
Anim Biotechnol ; 34(4): 1514-1523, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35167410

RESUMO

The purpose of this study was to explore the effects of Rice straw and King grass on apparent digestibility, ruminal bacterial, and fungus composition in buffaloes. Three ruminal fistulated buffaloes were used in a 3 × 2 Latin square design. The dietary treatments were king grass and straw hay. Experimental animals were kept in individual pens and concentrate was offered at 1 kg/d while roughage was fed ad libitum. Each period lasted for 15d, with the first 12d for an adaptation period, followed by a 3-day formal trial period. King grass has higher digestibility of protein. Rice straw has higher digestibility to cellulose. The results showed that when buffaloes were fed king grass and straw, Bacteroidetes were dominant in the rumen normal flora, but firmicutes were not. In addition, the results of this experiment suggest that increasing protein content in diets may be beneficial to increase the relative abundance of Proteobacteria. Similarly, higher dietary fiber content may be beneficial for increasing relative abundance of Prevotella and Staphylococcus. The dominant fungi in ruminal fluid 2 h after ingestion were aerobic fungi. These aerobic fungi most likely entered the rumen with food. Whether and how long aerobic fungi can survive in the rumen needs more research.


Assuntos
Oryza , Poaceae , Animais , Búfalos/metabolismo , Ração Animal/análise , Rúmen/metabolismo , Dieta
4.
Anim Biotechnol ; 34(9): 5075-5086, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37946542

RESUMO

The rumen is a complex ecosystem containing a variety of fungi, which are crucial for the digestive activities of ruminants. Previous research on rumen fungi has mainly focused on anaerobic fungi, given the rumen's reputation as a mainly anaerobic environment. The objective of this study was to investigate rumen fungal diversity and the presence of aerobic fungi in buffalo fed on different diets. Three adult buffaloes were used as experimental animals. Alfalfa hay, oat hay, whole corn silage, sugarcane shoot silage, fresh king grass, dried rice straw, and five kinds of mixed diets with concentrate to roughage ratios of 20:80, 35:65, 50:50, 65:35, and 80:20 were used as the experimental diets. The experimental animals were fed different diets for 22 days. Rumen fluid was collected from the rumen fistula for ITS (Internal Transcribed Spacer) sequencing 2 h after feeding on the morning of day 22. The results indicate the presence of large quantities of aerobic fungi in the rumen of the buffaloes 2 h after feeding and suggest that Ascomycota and Basidiomycota are the dominant fungal groups under different feeding conditions. The study also identified 62 different fungal types, which showed significant differences among the 11 experimental diets.


Assuntos
Búfalos , Rúmen , Animais , Feminino , Ração Animal/análise , Dieta/veterinária , Fungos , Lactação , Leite
5.
World J Microbiol Biotechnol ; 40(2): 51, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38146036

RESUMO

Vibrio alginolyticus (V. alginolyticus) is a common pathogen in the ocean. In addition to causing serious economic losses in aquaculture, it can also infect humans. The rapid detection of nucleic acids of V. alginolyticus with high sensitivity and specificity in the field is very important for the diagnosis and treatment of infection caused by V. alginolyticus. Here, we established a simple, fast and effective molecular method for the identification of V. alginolyticus that does not rely on expensive instruments and professionals. The method integrates recombinase polymerase amplification (RPA) technology with CRISPR system in a single PCR tube. Using this method, the results can be visualized by lateral flow dipstick (LFD) in less than 50 min, we named this method RPA-CRISPR/Cas13a-LFD. The method was confirmed to achieve high specificity for the detection of V. alginolyticus with no cross-reactivity with similar Vibrio and common clinical pathogens. This diagnostic method shows high sensitivity; the detection limit of the RPA-CRISPR/Cas13a-LFD is 10 copies/µL. We successfully identified 35 V. alginolyticus strains from a total of 55 different bacterial isolates and confirmed their identity by (Matrix-assisted laser desorption ionization time-of-flight mass spectrometry, MALDI-TOF MS). We also applied this method on infected mice blood, and the results were both easily and rapidly obtained. In conclusion, RPA-CRISPR/Cas13a-LFD offers great potential as a useful tool for reliable and rapid diagnosis of V. alginolyticus infection, especially in limited conditions.


Assuntos
Recombinases , Vibrio alginolyticus , Animais , Humanos , Camundongos , Recombinases/metabolismo , Vibrio alginolyticus/genética , Vibrio alginolyticus/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos
6.
Phys Chem Chem Phys ; 24(4): 2150-2157, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-34994764

RESUMO

Although magnesium rechargeable batteries (MRBs) have gained considerable attention, research relating to MRBs is still in its infancy. One issue is that magnesium ions are difficult to reversibly (de)intercalate in most electrode materials. Among various available cathodes, VO2(B) is a promising layered cathode material for use in MRBs. Totally different from monolayer VO2, the magnesiation mechanism in monoclinic bulk VO2(B) has not been clearly clarified to this day. For the first time, we systematically investigated the influence of magnetism and van der Waals (vdW) forces on the electronic structure and diffusion kinetics of magnesium in bulk VO2(B) using a series of DFT+U calculations. The Mg diffusivity can reach a high value of 1.62 × 10-7 cm2 s-1 at 300 K, which is comparable to Li+. These results demonstrate that VO2(B) is a potential host material with high mobility and fast kinetics.

7.
Small ; 15(13): e1805344, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30821911

RESUMO

Graphyne (GY) is a new type of carbon allotrope, which is viewed as a rapidly rising star in the carbon family referred to as 2D carbon allotropes due to its extraordinary properties. Considering the dynamic nature of the alkyne metathesis reaction, a hydrogen-substituted graphyne (HsGY) film is successfully synthesized on a gas/liquid interface using 1,3,5-tripynylbenzene (TPB) as the precursor. The synthesized HsGY film is used as a sulfur host matrix to be applied in lithium-sulfur batteries (LSBs). The HsGY@S electrode is prepared using S8 as sulfur source and presents excellent electrochemical performance.

8.
Curr Microbiol ; 74(8): 965-971, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28573341

RESUMO

The aim of this study was to develop a rapid detection assay to identify methicillin-resistant Staphylococcus aureus by simultaneous testing for the mecA, nuc, and femB genes using the loop-mediated isothermal amplification (LAMP) method. LAMP primers were designed using online bio-software ( http://primerexplorer.jp/e/ ), and amplification reactions were performed in an isothermal temperature bath. The products were then examined using 2% agarose gel electrophoresis. MecA, nuc, and femB were confirmed by triplex TaqMan real-time PCR. For better naked-eye inspection of the reaction result, hydroxy naphthol blue (HNB) was added to the amplification system. Within 60 min, LAMP successfully amplified the genes of interest under isothermal conditions at 63 °C. The results of 2% gel electrophoresis indicated that when the Mg2+ concentration in the reaction system was 6 µmol, the amplification of the mecA gene was relatively good, while the amplification of the nuc and femB genes was better at an Mg2+ concentration of 8 µmol. Obvious color differences were observed by adding 1 µL (3.75 mM) of HNB into 25 µL reaction system. The LAMP assay was applied to 128 isolates cases of methicillin-resistant Staphylococcus aureus, which were separated from the daily specimens and identified by Vitek microbial identification instruments. The results were identical for both LAMP and PCR. LAMP offers an alternative detection assay for mecA, nuc, and femB and is faster than other methods.


Assuntos
Proteínas de Bactérias/genética , Técnicas Bacteriológicas/métodos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Nuclease do Micrococo/genética , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Proteínas de Ligação às Penicilinas/genética , Eletroforese em Gel de Ágar , Staphylococcus aureus Resistente à Meticilina/genética , Naftalenossulfonatos/metabolismo , Coloração e Rotulagem , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia
9.
J Org Chem ; 81(6): 2320-6, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26909857

RESUMO

Metal-catalyzed transfer hydroformylation is an important way of cleaving C-C bonds and constructing new double bonds. The newly reported density functional theory (DFT) method, M11-L, has been used to clarify the mechanism of the rhodium-catalyzed transfer hydroformylation reported by Dong et al. DFT calculations depict a deformylation and formylation reaction pathway. The deformylation step involves an oxidative addition to the formyl C-H bond, deprotonation with a counterion, decarbonylation, and ß-hydride elimination. After olefin exchange, the formylation step takes place via olefin insertion into the Rh-H bond, carbonyl insertion, and a final protonation with the conjugate acid of the counterion. Theoretical calculations indicate that the alkalinity of the counterion is important for this reaction because both deprotonation and protonation occur during the catalytic cycle. A theoretical study into the formyl acceptor shows that the driving force of the reaction is correlated with the stability of the unsaturated bond in the acceptor. Our computational results suggest that alkynes or ring-strained olefins could be used as formyl acceptors in this reaction.

10.
Bioorg Med Chem Lett ; 25(18): 3897-9, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26243371

RESUMO

Structure-activity relationships (SAR) in 2,5-dichloro-N-(2-methyl-4-nitrophenyl)benzenesulfonamide (FH535) were examined as part of a program to identify agents that inhibit the Wnt/ß-catenin signaling pathway that is frequently upregulated in hepatocellular carcinoma (HCC). FH535 was reported as an inhibitor of both ß-catenin in the Wnt signaling pathway and the peroxisome proliferator-activated receptor (PPAR). A ß-catenin/T-cell factor (TCF)/Lymphoid-enhancer factor (LEF)-dependent assay (i.e., luciferase-based TOPFlash assay) as well as a [(3)H]-thymidine incorporation assay were used to explore SAR modifications of FH535. Although replacing the 2,5-dichlorophenylsulfonyl substituent in FH535 with a 2,6-dihalogenation pattern generally produced more biologically active analogs than FH535, other SAR modifications led only to FH535 analogs with comparable or slightly improved activity in these two assays. The absence of a clear SAR pattern in activity suggested a multiplicity of target effectors for N-aryl benzenesulfonamides.


Assuntos
Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Sulfonamidas/farmacologia , Timidina/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Benzenossulfonamidas
11.
Dalton Trans ; 53(35): 14767-14778, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39162081

RESUMO

To overcome the disadvantages of poor intrinsic conductivity and stability of ZnCo2O4, a ZnCo2O4@MnMoO4 composite as an emerging pseudocapacitor electrode material with high specific capacitance, environmental friendliness, morphological diversity, and unique hierarchical structure was synthesized via a simple two-step hydrothermal method. The research results indicate that the ZnCo2O4@MnMoO4 composite can present a high specific capacity of 1628 F g-1 at a current density of 1 A g-1 and good cycling stability with 69% capacity retention after 10 000 cycles at 10 A g-1. Hybrid supercapacitors (HSCs) assembled with the ZnCo2O4@MnMoO4 cathode and activated carbon anode can deliver an energy density of 48 W h kg-1 at a power density of 695 W kg-1, and their capacity retention reached 61% after 8000 charge-discharge cycles at a current density of 10 A g-1. This could be attributed to the synergistic effect of the specific surface area and electrical conductivity enhanced by compositing ZnCo2O4 with MnMoO4. As a result, the excellent electrochemical properties show that the ZnCo2O4@MnMoO4 composite has strong application potential for high-performance supercapacitors.

12.
Infect Med (Beijing) ; 3(2): 100111, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38948389

RESUMO

Background: Swift and accurate detection of Vibrio parahaemolyticus, which is a prominent causative pathogen associated with seafood contamination, is required to effectively combat foodborne disease and wound infections. The toxR gene is relatively conserved within V. parahaemolyticus and is primarily involved in the expression and regulation of virulence genes with a notable degree of specificity. The aim of this study was to develop a rapid, simple, and constant temperature detection method for V. parahaemolyticus in clinical and nonspecialized laboratory settings. Methods: In this study, specific primers and CRISPR RNA were used to target the toxR gene to construct a reaction system that combines recombinase polymerase amplification (RPA) with CRISPR‒Cas13a. The whole-genome DNA of the sample was extracted by self-prepared sodium dodecyl sulphate (SDS) nucleic acid rapid extraction reagent, and visual interpretation of the detection results was performed by lateral flow dipsticks (LFDs). Results: The specificity of the RPA-CRISPR/Cas13a-LFD method was validated using V. parahaemolyticus strain ATCC-17802 and six other non-parahaemolytic Vibrio species. The results demonstrated a specificity of 100%. Additionally, the genomic DNA of V. parahaemolyticus was serially diluted and analysed, with a minimum detectable limit of 1 copy/µL for this method, which was greater than that of the TaqMan-qPCR method (102 copies/µL). The established methods were successfully applied to detect wild-type V. parahaemolyticus, yielding results consistent with those of TaqMan-qPCR and MALDI-TOF MS mass spectrometry identification. Finally, the established RPA-CRISPR/Cas13a-LFD method was applied to whole blood specimens from mice infected with V. parahaemolyticus, and the detection rate of V. parahaemolyticus by this method was consistent with that of the conventional PCR method. Conclusions: In this study, we describe an RPA-CRISPR/Cas13a detection method that specifically targets the toxR gene and offers advantages such as simplicity, rapidity, high specificity, and visual interpretation. This method serves as a valuable tool for the prompt detection of V. parahaemolyticus in nonspecialized laboratory settings.

13.
Chem Commun (Camb) ; 60(18): 2540-2543, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38332746

RESUMO

A NiB binary catalyst with a unique mulberry-like nanoparticle morphology has been prepared by one-step electrodeposition. The NiB-0.2 catalyst exhibits excellent catalytic activity, selectivity, and stability for the borohydride oxidation reaction. Moreover, a direct borohydride fuel cell using the NiB-0.2 catalyst anode can deliver a peak power density of 453 mW cm-2 and open-circuit voltage of 1.96 V at 343 K. The improved performances are due to the introduction of B. This study may inspire the development of efficient noble-metal-free anode catalysts for DBFCs.

14.
Front Microbiol ; 15: 1325505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38318339

RESUMO

The rumen serves as a complex ecosystem, harboring diverse microbial communities that play crucial ecological roles. Because previous studies have predominantly focused on anaerobic microorganisms, limited attention has been given to aerobic microorganisms in the goat rumen. This study aims to explore the diversity of aerobic microorganisms in the rumen and understand their niche and ecological roles. Rumen fluid samples were collected from 6 goats at different time points post-morning feeding. pH, NH3-N, and volatile fatty acid (TVFA) concentrations were measured, while In vitro cultivation of aerobic microorganisms was performed using PDA medium. Internal Transcribed Spacer (ITS) and 16S sequencing unveiled microbial diversity within the rumen fluid samples. Evidence of obligate aerobic microorganisms in the goat rumen suggests their potential contribution to ecological functionalities. Significantly, certain aerobic microorganisms exhibited correlations with TVFA levels, implying their involvement in TVFA metabolism. This study provides evidence of the existence and potential ecological roles of obligate aerobic microorganisms in the goat rumen. The findings underscore the significance of comprehensively deciphering goat rumen microbial communities and their interactions, with aerobes regarded as permanent residents rather than transients. These insights form a solid foundation for advancing our understanding of the intricate interplay between goat and their aerobic microorganisms in the rumen.

15.
Dalton Trans ; 53(12): 5416-5426, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38450555

RESUMO

The development of an electrochemical energy storage system with exceptional performance is an important way to address the energy crisis and environmental pollution of the modem world. In this study, an NiCo2O4@MnS composite with a unique hierarchical structure has been successfully synthesized on an NF substrate using the hydrothermal-electrodeposition method. The results indicate that NiCo2O4@MnS possesses superior specific capacitance and excellent cycling stability. At a current density of 2 A g-1, its specific capacitance can reach 2100 F g-1, while the capacitance retention is still 76% after 10 000 cycles at 10 A g-1. Moreover, when the current density is 1 A g-1, the assembled NiCo2O4@MnS//AC device can deliver a specific capacitance of 203 F g-1, and the energy density is up to 55 W h kg-1 at a power density of 697 W kg-1. These outstanding electrochemical properties of NiCo2O4@MnS can be ascribed to the increase in ion diffusion, specific surface area and electronic conductivity due to its unique hierarchical structure and introduction of MnS.

16.
Int J Biol Macromol ; 275(Pt 2): 133720, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38987000

RESUMO

Tick-borne encephalitis virus (TBEV), a zoonotic pathogen, can cause severe neurological complications and fatal outcomes in humans. Early diagnosis of TBEV infection is crucial for clinical practice. Although serological assays are frequently employed for detection, the lack of antibodies in the early stages of infection and the cross-reactivity of antibodies limit their efficacy. Conventional molecular diagnostic methods such as RT-qPCR can achieve early and accurate identification but require specialized instrumentation and professionals, hindering their application in resource-limited areas. Our study developed a rapid and visual TBEV molecular detection method by combining RT-recombinase-aided amplification, the CRISPR/Cas13a system, and lateral flow dipsticks. The diagnostic sensitivity of this method is 50 CFU/ml, with no cross-reactivity with a variety of viruses. The detection can be carried out within 1 h at a temperature between 37 and 42 °C, and the results can be visually determined without the need for complex instruments and professionals. Subsequently, this assay was used to analyze clinical samples from 15 patients suspected of TBEV infection and 10 healthy volunteers, and its sensitivity and specificity reached 100 %, which was consistent with the results of RT-qPCR. These results indicate that this new method can be a promising point-of-care test for the diagnosis of tick-borne encephalitis.


Assuntos
Sistemas CRISPR-Cas , Vírus da Encefalite Transmitidos por Carrapatos , Recombinases , Vírus da Encefalite Transmitidos por Carrapatos/genética , Humanos , Recombinases/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/virologia , Encefalite Transmitida por Carrapatos/sangue , Sensibilidade e Especificidade , RNA Viral/genética , Técnicas de Diagnóstico Molecular/métodos
17.
Am J Pathol ; 180(2): 661-71, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22182699

RESUMO

Interferon (IFN)-γ plays crucial roles in regulating both innate and adaptive immunity. The existence of IFN-γ receptor 1 (IFNGR1) molecules on the cell surface is a prerequisite to the initiation of IFN-γ signaling; low expression of IFNGR1 leads to a functional blockade of IFN-γ signaling. However, the molecular mechanisms by which IFNGR1 expression is controlled are unclear. In the present study, we demonstrated that IFNGR1 expression was reduced or lost in breast cancer. Heterogeneous IFNGR1 immunoreactivity appeared to be associated with the morphological heterogeneity of breast cancer, and loss of IFNGR1 expression was predominantly observed in poorly differentiated areas. We identified the functional activating protein (AP)-2 and specificity protein (SP)-1 sites within the IFNGR1 promoter. Ectopic expression of AP-2α drastically repressed the expression of IFNGR1 and hindered IFN-γ signaling, whereas AP-2α gene silencing elevated IFNGR1 levels. Overexpression of SP-1 effectively antagonized the repressive effects of AP-2α. Simultaneous recruitment of both transcription factors to the AP-2 and SP-1 motifs, respectively, in the IFNGR1 promoter was demonstrated, implying that AP-2α and SP-1 may synergistically modulate IFNGR1 transcription. Moreover, AP-2α overexpression in AP-2-deficient SW480 cells remarkably inhibited Stat1 phosphorylation and the anti-proliferative effects of IFN-γ, whereas knockdown of the AP-2α expression dramatically enhanced the sensitivities of HeLa cells highly expressing AP-2 to IFN-γ, indicating that dysregulation of AP-2α expression is associated with impaired IFN-γ actions in cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Interferon gama/antagonistas & inibidores , Receptores de Interferon/metabolismo , Fator de Transcrição Sp1/fisiologia , Fator de Transcrição AP-2/fisiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Inativação Gênica/fisiologia , Humanos , Fosforilação , RNA Interferente Pequeno/fisiologia , Receptores de Interferon/genética , Fator de Transcrição STAT1/antagonistas & inibidores , Transdução de Sinais/fisiologia , Fator de Transcrição Sp1/metabolismo , Transfecção , Regulação para Cima , Receptor de Interferon gama
18.
J Surg Res ; 185(1): 225-30, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23769634

RESUMO

BACKGROUND: Deregulated Ras/Raf/mitogen-activated protein kinase and PI3 K/AKT/mTOR signaling pathways are significant in hepatocellular carcinoma proliferation (HCC). In this study we evaluated differences in the antiproliferative effect of dual PI3 K/Akt/mTOR and Ras/Raf/mitogen-activated protein kinase inhibition of non liver cancer stem cell lines (PLC and HuH7) and liver cancer stem cell (LCSC) lines (CD133, CD44, CD24, and aldehyde dehydrogenase 1-positive cells). MATERIALS AND METHODS: Flow cytometry was performed on the resulting tumors to identify the LCSC markers CD133, CD44, CD24, and aldehyde dehydrogenase 1. Methylthiazol tetrazolium assay was used to assess cellular proliferation. Finally, a Western blot assay was used to evaluate for inhibition of specific enzymes in these two signaling pathways. RESULTS: Using flow cytometry, we found that LCSC contain 64.4% CD133 + cells, 83.2% CD44 + cells, and 96.4% CD24 + cells. PKI-587 and sorafenib caused inhibiton of LCSC and HCC cell proliferation. PLC cells were more sensitive to PKI-587 than LCSC or Huh7 (P < 0.001). Interestingly, HuH7 cells were more sensitive to sorafenib than LCSC or PLC cells. Additionally, combination therapy with PKI-587 and sorafenib caused significantly more inhibition than monotherapy in HuH7, PLC, and LCSC. Using the methylthiazol tetrazolium assay, we found that the LCSC proliferation was inhibited with sorafenib monotherapy 39% at 5 µM (P < 0.001; n = 12) and 67% by PKI-587 at 0.1 µM (P = 0.002, n = 12) compared with control. The combination of PKI-587 and sorafenib, however, synergistically inhibited LCSC proliferation by 86% (P = 0.002; n = 12). CONCLUSIONS: LCSC (CD133+, CD44+, CD24+) were able to develop very aggressive tumors with low cell concentrations at 4 to 6 wk. Cells CD133+, CD44+, CD24+, which demonstrated at least moderate resistance to therapy in vitro. The combination of PKI-587 and sorafenib was better than either drug alone at inhibiting of LCSC and on HCC cell proliferation.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Morfolinas/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Triazinas/farmacologia , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Neoplásicas/citologia , Niacinamida/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sorafenibe , Serina-Treonina Quinases TOR/metabolismo , Quinases raf/metabolismo
19.
J Org Chem ; 78(11): 5218-26, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23675863

RESUMO

Under open-flask conditions in the presence of commercially available FeCl3·6H2O, N,N-disubstituted anilines can be converted into diversely functionalized benzidines with yields of up to 99%. Oxidative coupling was extended to N-monosubstituted anilines, and the method was applied to the efficient preparation of 6,6'-biquinoline. Mechanistic investigations have also been performed to explain the observed reactivities.


Assuntos
Compostos de Anilina/química , Benzidinas/síntese química , Cloretos/química , Compostos Férricos/química , Benzidinas/química , Estrutura Molecular , Oxirredução , Espectrofotometria Ultravioleta
20.
J Pathol ; 228(2): 148-57, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22287315

RESUMO

Glucocorticoids are stress-responsive neuroendocrine mediators and play an important role in malignant progression, especially in solid tumours. We demonstrate a novel mechanism by which glucocorticoids modulate p53-dependent miR-145 expression in HPV-positive cervical cancer cells through induction of E6 proteins. We found that expression of miR-145 was reduced in cervical cancer tissues. Cortisol induced HPV-E6 expression and suppressed p53 and miR-145 in cervical cancer cells. MiR-145 expression in cervical cancer cells was wild-type p53-dependent, and cortisol-induced down-regulation of miR-145 expression prevented chemotherapy-induced apoptosis, whereas over-expression of miR-145 enhanced sensitivity to mitomycin and reversed the chemoresistance induced by glucocorticoids. We also show that miR-145 augments the effects of p53 by suppressing the inhibitors of p53 in cervical cancer cells, suggesting that miR-145 plays a role in p53 tumour suppression. Finally, we demonstrate that miR-145 inhibits both the motility and invasion of cervical cancer cells. Our findings identify a novel pathway through which the neuroendocrine macroenvironment affects cervical tumour growth, invasion and therapy resistance and show that miR-145 may serve as a target for cervical cancer therapy. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hidrocortisona/farmacologia , MicroRNAs/genética , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/genética , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/virologia , Anti-Inflamatórios/farmacologia , Apoptose , Northern Blotting , Ensaios de Migração Celular , Proteínas de Ligação a DNA , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Citometria de Fluxo , Células HeLa , Humanos , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/virologia
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