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1.
Sensors (Basel) ; 24(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38339615

RESUMO

As cyber-attacks increase in unencrypted communication environments such as the traditional Internet, protected communication channels based on cryptographic protocols, such as transport layer security (TLS), have been introduced to the Internet. Accordingly, attackers have been carrying out cyber-attacks by hiding themselves in protected communication channels. However, the nature of channels protected by cryptographic protocols makes it difficult to distinguish between normal and malicious network traffic behaviors. This means that traditional anomaly detection models with features from packets extracted a deep packet inspection (DPI) have been neutralized. Recently, studies on anomaly detection using artificial intelligence (AI) and statistical characteristics of traffic have been proposed as an alternative. In this review, we provide a systematic review for AI-based anomaly detection techniques over encrypted traffic. We set several research questions on the review topic and collected research according to eligibility criteria. Through the screening process and quality assessment, 30 research articles were selected with high suitability to be included in the review from the collected literature. We reviewed the selected research in terms of dataset, feature extraction, feature selection, preprocessing, anomaly detection algorithm, and performance indicators. As a result of the literature review, it was confirmed that various techniques used for AI-based anomaly detection over encrypted traffic were used. Some techniques are similar to those used for AI-based anomaly detection over unencrypted traffic, but some technologies are different from those used for unencrypted traffic.

2.
J Enzyme Inhib Med Chem ; 38(1): 2189097, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36927348

RESUMO

The design of kinase inhibitors targeting the oncogenic kinase BCR-ABL constitutes a promising paradigm for treating chronic myeloid leukaemia (CML). Nevertheless, the efficacy of imatinib, the first FDA-approved targeted therapy for CML, is curbed by the emergence of resistance. Herein, we report the identification of the 2-methoxyphenyl ureidobenzothiazole AK-HW-90 (2b) as a potent pan-BCR-ABL inhibitor against imatinib-resistant mutants, particularly T315I. A concise array of six compounds 2a-f was designed based on our previously reported benzothiazole lead AKE-5l to improve its BCR-ABLT315I inhibitory activity. Replacing the 6-oxypicolinamide moiety of AKE-5l with o-methoxyphenyl and changing the propyl spacer with phenyl afforded 2a and AK-HW-90 (2b) with IC50 values of 2.0 and 0.65 nM against BCR-ABLT315I, respectively. AK-HW-90 showed superior anticancer potency to imatinib against multiple cancer cells (NCI), including leukaemia K-562. The obtained outcomes offer AK-HW-90 as a promising candidate for the treatment of CML and other types of cancer.


Assuntos
Proteínas de Fusão bcr-abl , Pirimidinas , Mesilato de Imatinib/farmacologia , Proteínas de Fusão bcr-abl/genética , Pirimidinas/farmacologia , Piperazinas/farmacologia , Benzamidas/farmacologia , Apoptose
3.
Sensors (Basel) ; 23(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38139701

RESUMO

Cyber threats to industrial control systems (ICSs) have increased as information and communications technology (ICT) has been incorporated. In response to these cyber threats, we are implementing a range of security equipment and specialized training programs. Anomaly data stemming from cyber-attacks are crucial for effectively testing security equipment and conducting cyber training exercises. However, securing anomaly data in an ICS environment requires a lot of effort. For this reason, we propose a method for generating anomaly data that reflects cyber-attack characteristics. This method uses systematic sampling and linear regression models in an ICS environment to generate anomaly data reflecting cyber-attack characteristics based on benign data. The method uses statistical analysis to identify features indicative of cyber-attack characteristics and alters their values from benign data through systematic sampling. The transformed data are then used to train a linear regression model. The linear regression model can predict features because it has learned the linear relationships between data features. This experiment used ICS_PCAPS data generated based on Modbus, frequently used in ICS. In this experiment, more than 50,000 new anomaly data pieces were generated. As a result of using some of the new anomaly data generated as training data for the existing model, no significant performance degradation occurred. Additionally, comparing some of the new anomaly data with the original benign and attack data using kernel density estimation confirmed that the new anomaly data pattern was changing from benign data to attack data. In this way, anomaly data that partially reflect the pattern of the attack data were created. The proposed method generates anomaly data like cyber-attack data quickly and logically, free from the constraints of cost, time, and original cyber-attack data required in existing research.

4.
J Am Chem Soc ; 144(35): 16131-16138, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36007154

RESUMO

Single-atom catalysts (SACs) of non-precious transition metals (TMs) often show unique electrochemical performance, including the electrochemical carbon dioxide reduction reaction (CO2RR). However, the inhomogeneity in their structures makes it difficult to directly compare SACs of different TM for their CO2RR activity, selectivity, and reaction mechanisms. In this study, the comparison of isolated TMs (Fe, Co, Ni, Cu, and Zn) is systematically investigated using a series of crystalline molecular catalysts, namely TM-coordinated phthalocyanines (TM-Pcs), to directly compare the intrinsic role of the TMs with identical local coordination environments on the CO2RR performance. The combined experimental measurements, in situ characterization, and density functional theory calculations of TM-Pc catalysts reveal a TM-dependent CO2RR activity and selectivity, with the free energy difference of ΔG(*HOCO) - ΔG(*CO) being identified as a descriptor for predicting the CO2RR performance.

5.
Phys Chem Chem Phys ; 23(12): 7048-7056, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33625420

RESUMO

We report on rotationally resolved laser induced fluorescence (LIF) and vibrationally resolved resonance-enhanced multiphoton ionization (REMPI) spectroscopy of the chiral molecule 1-indanol. Spectra of the S1← S0 electronic transition are recorded in a jet-cooled, pulsed molecular beam. Using two time-delayed pulsed lasers, the lifetimes of the S1 state of the two most stable conformers, referred to as eq1 and ax2, have been determined. The S1← S0 origin bands of these conformers as well as the transition to a vibrationally excited level in the S1 state of eq1 are recorded with full rotational resolution (25 MHz observed linewidth) by measuring the LIF intensity following excitation with a tuneable, narrowband cw laser. On selected rotationally resolved electronic transitions, Lamb-dips are measured to confirm the Lorentzian lifetime-contribution to the observed lineshapes. The rotationally resolved S1← S0 origin band of a neon-complex of eq1 is measured via LIF as well. The fit of the rotationally resolved LIF spectra of the origin bands to those of an asymmetric rotor yields a standard deviation of about 6 MHz. The resulting spectroscopic parameters are tabulated and compared to the outcome of ab initio calculations. For both conformers as well as for the Ne-eq1 complex, the geometric structures in the S0 and S1 states are discussed. For all systems, the transition dipole moment is mainly along the a-axis, the contributions along the b- and c-axes being about one order of magnitude smaller.

6.
Phys Chem Chem Phys ; 23(13): 8030-8036, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33587734

RESUMO

We report on an experimental test of Babinet's principle in quantum reflection of an atom beam from diffraction gratings. The He beam is reflected and diffracted from a square-wave grating at near grazing-incidence conditions. According to Babinet's principle the diffraction peak intensities (except for the specular-reflected beam) are expected to be identical for any pair of gratings of complementary geometry. We observe conditions where Babinet's principle holds and also where it fails. Our data indicate breakdown conditions when either the incident or a diffracted beam propagates close to the grating surface. At these conditions, the incident or the diffracted He beam is strongly affected by the dispersive interaction between the atoms and the grating surface. Babinet's principle is also found to break down, when the complementary grating pair shows a large asymmetry in the strip widths. For very small strip widths, edge diffraction from half planes becomes dominant, whereas for the complementary wide strips the atom-surface interactions leads to a strong reduction of all non-specular diffraction peak intensities.

7.
Int J Mol Sci ; 21(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317068

RESUMO

Inhibition of the molecular chaperone heat shock protein 90 (Hsp90) represents a promising approach for cancer treatment. BIIB021 is a highly potent Hsp90 inhibitor with remarkable anticancer activity; however, its clinical application is limited by lack of potency and response. In this study, we aimed to investigate the impact of replacing the hydrophobic moiety of BIIB021, 4-methoxy-3,5-dimethylpyridine, with various five-membered ring structures on the binding to Hsp90. A focused array of N7/N9-substituted purines, featuring aromatic and non-aromatic rings, was designed, considering the size of hydrophobic pocket B in Hsp90 to obtain insights into their binding modes within the ATP binding site of Hsp90 in terms of π-π stacking interactions in pocket B as well as outer α-helix 4 configurations. The target molecules were synthesized and evaluated for their Hsp90α inhibitory activity in cell-free assays. Among the tested compounds, the isoxazole derivatives 6b and 6c, and the sole six-membered derivative 14 showed favorable Hsp90α inhibitory activity, with IC50 values of 1.76 µM, 0.203 µM, and 1.00 µM, respectively. Furthermore, compound 14 elicited promising anticancer activity against MCF-7, SK-BR-3, and HCT116 cell lines. The X-ray structures of compounds 4b, 6b, 6c, 8, and 14 bound to the N-terminal domain of Hsp90 were determined in order to understand the obtained results and to acquire additional structural insights, which might enable further optimization of BIIB021.


Assuntos
Antineoplásicos/síntese química , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Adenina/análogos & derivados , Adenina/química , Adenina/farmacologia , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Células HCT116 , Proteínas de Choque Térmico HSP90/química , Humanos , Isoxazóis/química , Células MCF-7 , Camundongos , Ligação Proteica , Piridinas/química , Piridinas/farmacologia , Relação Estrutura-Atividade
8.
Phys Rev Lett ; 122(4): 040401, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768348

RESUMO

We report on reflection and diffraction of beams of He and D_{2} from square-wave gratings of a 400-µm period and strip widths ranging from 10 to 200 µm at grazing-incidence conditions. In each case we observe fully resolved matter-wave diffraction patterns including the specular reflection and diffracted beams up to the second diffraction order. With decreasing strip width, the observed diffraction efficiencies exhibit a transformation from the known regime of quantum reflection from the grating strips to the regime of edge diffraction from a half-plane array. The latter is described by a single-parameter model developed previously to describe phenomena as diverse as quantum billiards, scattering of radio waves in urban areas, and reflection of matter waves from microstructures. Our data provide experimental confirmation of the widespread model. Moreover, our results demonstrate that neither classical reflection nor quantum reflection are essential for reflective diffraction of matter waves from a structured solid, but it can result exclusively from half-plane edge diffraction.

9.
Bioorg Med Chem ; 26(21): 5596-5611, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30385226

RESUMO

Two new series of 5-subtituted and 5,6-disubstituted pyrrolo[2,3-d]pyrimidine octamides (4a-o and 6a-g) and their corresponding free amines 5a-m and 7a-g have been synthesized and biologically evaluated for their antiproliferative activity against three human cancer cell lines. The 5,6-disubstituted octamides 6d-g as well as the amine derivative 7b have shown the best anticancer activity with single digit micromolar GI50 values over the tested cancer cells, and low cytotoxic effects (GI50 > 10.0 µM) against HFF-1 normal cell. A structure activity relationship (SAR) study has been established and disclosed that terminal octamide moiety at C2 as well as disubstitution with fluorobenzyl piperazines at C5 and C6 of pyrrolo[2,3-d]pyrimidine are the key structural features prerequisite for best antiproliferative activity. Moreover, the most active member 6f was tested for its antiproliferative activity over a panel of 60 cancer cell lines at NCI, and exhibited distinct broad spectrum anticancer activity with submicromolar GI50 and TGI values over multiple cancer cells. Kinase profile of compound 6f over 53 oncogenic kinases at 10 µM concentration showed its highly selective inhibitory activity towards FGFR4, Tie2 and TrkA kinases. The observed activity of 6f against TrkA (IC50 = 2.25 µM), FGFR4 (IC50 = 6.71 µM) and Tie2 (IC50 = 6.84 µM) was explained by molecular docking study, which also proposed that 6f may be a type III kinase inhibitor, binding to an allosteric site rather than kinase hinge region. Overall, compound 6f may serve as a promising anticancer lead compound that could be further optimized for development of potent anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/farmacocinética , Pirróis/síntese química , Pirróis/química , Pirróis/farmacocinética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/química , Receptor TIE-2/antagonistas & inibidores , Receptor TIE-2/química , Receptor trkA/antagonistas & inibidores , Receptor trkA/química
10.
Bioorg Med Chem Lett ; 27(2): 237-241, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914802

RESUMO

A novel series of heat shock protein 90 (Hsp90) inhibitors was identified by X-ray crystal analysis of complex structures at solvent-exposed exit pocket C. The 2-amino-pyrrolo[2,3-d]pyrimidine derivatives, 7-deazapurines substituted with a benzyl moiety at C5, showed potent Hsp90 inhibition and broad-spectrum antiproliferative activity against NCI-60 cancer cell lines. The most potent compound, 6a, inhibited Hsp90 with an IC50 of 36nM and showed a submicromolar mean GI50 value against NCI-60 cell lines. The interaction of 6a at the ATP-binding pocket of Hsp90 was confirmed by X-ray crystallography and Western blot analysis.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Pirimidinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
11.
Chemphyschem ; 17(22): 3670-3676, 2016 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-27748011

RESUMO

Molecular beams of He and D2 are scattered from a ruled diffraction grating in conical-mount geometry under grazing-incidence conditions. Fully resolved diffraction patterns as a function of detection angle are recorded for different grating azimuth angles and for two different kinetic energies of the particle beams. Variations in diffraction peak widths are traced back to different velocity spreads of He and D2 determined by time-of-flight measurements. A comprehensive analysis of diffraction intensities confirms universal diffraction, that is, for identical de Broglie wavelengths, the relative diffraction intensities for He and D2 are the same. Universal diffraction results from peculiarities of quantum reflection of the atoms and molecules from the diffraction grating. In quantum reflection particles scatter many nanometers in front of the surface from the long-range attractive branch of the particle-surface interaction potential without probing the potential well and the short-range repulsive branch of the potential.

12.
Chem Pharm Bull (Tokyo) ; 62(12): 1214-24, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25297523

RESUMO

A novel series of oxazolidinone-class antimicrobial agents with 5-substituted octahydrocyclopenta[c]pyrrole moieties at the C-ring of linezolid and an acetamide or 1,2,3-triazole ring as the C-5 side chain of the oxazolidinone ring were prepared. The resulting series of compounds were evaluated for in vitro antimicrobial activity against Mycobacterium tuberculosis and a panel of clinically important resistant Gram-positive and -negative bacteria. Among them, endo-alcohol 2a and exo-alcohol 2b showed potent inhibitory activity against M. tuberculosis H37Rv, which was superior to that of linezolid. Several analogues in this series showed potent in vitro antibacterial activity against the clinically important vancomycin-resistant bacteria and showed similar or better potency against linezolid-resistant methicillin-resistant Staphylococcus aureus (MRSA) strains. The hydroxyl group in the azabicyclic C-ring interacted with the same hydrophobic pocket as linezolid based on a docking study. Selected compounds with high antimicrobial activity showed good human microsomal stability and low CYP isozyme and monoamine oxidase (MAO) inhibition.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Antituberculosos/síntese química , Antituberculosos/farmacologia , Compostos Azabicíclicos/síntese química , Compostos Azabicíclicos/farmacologia , Oxazóis/síntese química , Oxazóis/farmacologia , Pirrolidinas/síntese química , Pirrolidinas/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Inibidores Enzimáticos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Inibidores da Monoaminoxidase/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Resistência a Vancomicina
13.
ACS Nano ; 18(3): 1995-2005, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38214304

RESUMO

Transition metal (TM) based Prussian whites, comprising a cyanide anion ((C≡N)-) and TM cations in an alternative manner, have been widely adopted as cathode materials for rechargeable batteries. Prussian whites are characterized by the TM electronic states that exclusively adopt low spin (LS) toward the C atom and high spin (HS) toward the N atom through the hybridized covalent bonding in the TM─C≡N─TM unit with the average oxidation states of the TM ions being 2+, considerably affecting the phase transition behavior upon the release and storage of carrier ions; however, there have been only a few studies on their associated features. Herein, Prussian whites with different HS TM ions were synthesized via coprecipitation and the phase transition behavior controlled by the π electron interaction between the cyanide anions and TM ions during battery operations was investigated. In situ X-ray characterizations reveal that the combined effect of π backdonation in the LS Fe-C unit and π donation in the HS TM-N unit effectively controls the bond length of the TM─C≡N─TM building unit, thus markedly influencing the lattice volume of a series of Prussian white cathodes during the charge/discharge process. This study presents a comprehensive understanding of the structure-property relationship of the Prussian white cathodes involving π electron interactions during battery operations.

14.
J Nanosci Nanotechnol ; 13(5): 3437-40, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23858874

RESUMO

A unique synthesis method was developed, which is called solution combustion method (SCM). TiO2 nanopowder was synthesized by this method. This SCM TiO2 nanopowder (-35 nm) was added to the dielectric layer of AC powder electroluminescence (EL) device. The dielectric layer was made of commercial BaTiO3 powder (-1.2 microm) and binding polymer. 0, 5, 10 and 15 wt% of SCM TiO2 nanopowder was added to the dielectric layer during fabrication of AC powder EL device respectively. Dielectric constant of these four kinds of dielectric layers was measured. The brightness and current density of AC powder EL device were also measured. When 10 wt% of SCM TiO2 nanopowder was added, dielectric constant and brightness were increased by 30% and 101% respectively. Furthermore, the current density was decreased by 71%. This means that the brightness was double and the power consumption was one third.


Assuntos
Compostos de Bário/química , Medições Luminescentes/instrumentação , Nanoestruturas/química , Titânio/química , Compostos de Bário/efeitos da radiação , Campos Eletromagnéticos , Desenho de Equipamento , Análise de Falha de Equipamento , Temperatura Alta , Luz , Nanoestruturas/efeitos da radiação , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Pós , Soluções , Titânio/efeitos da radiação
15.
ACS Appl Mater Interfaces ; 15(29): 35149-35160, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37439627

RESUMO

In this study, we incorporated TiN as a carrier suppressor into an amorphous InZnO channel to achieve stable channels for thin-film transistors (TFTs) and light-emitting transistors (LETs). The low electronegativity and standard electrode potential of the Ti dopant led to a reduction in the number of oxygen vacancies in the InZnO channel. Moreover, the substitution of nitrogen into the oxygen sites of InZnO effectively decreased the excess electrons. As a result, the cosputtering of the TiN dopant resulted in a decrease in the carrier concentration of the InZnO channel, serving as an effective carrier suppressor. Due to the distinct structures of TiN and InZnO, the TiN-doped InZnO channel exhibited a completely amorphous structure and a featureless surface morphology. The presence of oxygen vacancies in the InZnO channel creates trap states for electrons and holes. Consequently, the TFT with the InZnTiON channel demonstrated an improved subthreshold swing and enhanced stability during the gate bias stress test. Furthermore, the threshold voltage shift (ΔVth) changed from 3.29 to 0.86 V in the positive bias stress test and from -0.92 to -0.09 V in the negative bias stress test. Additionally, we employed an InZnTiON channel in LETs as a substitute for organic semiconductors. The reduction in the number of oxygen vacancies effectively prevented exciton quenching caused by hole traps within the vacancies. Consequently, appropriate TiN doping in the InZnO channel enhanced the intensity of the LET devices.

16.
ACS Appl Mater Interfaces ; 15(6): 7939-7948, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36625754

RESUMO

Layered lithium cobalt oxide (LiCoO2, LCO), which serves as a structural motif for the widely adopted layered cathodes in lithium-ion batteries, has a long history, and its unstable phase transition during high-voltage operation (∼4.5 V) remains an intractable problem. Many research strategies, such as surface coating and immobile ion doping, have been proposed to address this issue, but a clear understanding of the effects has not been demonstrated because of various potential parameters (e.g., particle size, shape, and dopant content). Herein, we report a molten salt synthesis method that produces sphere-like single-crystal magnesium (Mg)-doped LCO. In situ X-ray diffraction and X-ray absorption fine structure analyses confirmed that the lattice strain was effectively alleviated by the effects of both the particle shape and Mg doping compared to the plate-like and sphere-like single-crystal LCO samples. Furthermore, the preference for Mg doping in the Co site (3b) rather than in the Li site (3a) in the LCO framework is systematically revealed, and a clear understanding of Mg doping that suppresses the monoclinic phase transition is discussed in detail.

17.
Cancer Res Commun ; 3(6): 1078-1092, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37377604

RESUMO

Triple-negative breast cancer (TNBC) has high relapse and metastasis rates and a high proportion of cancer stem-like cells (CSC), which possess self-renewal and tumor initiation capacity. MELK (maternal embryonic leucine zipper kinase), a protein kinase of the Snf1/AMPK kinase family, is known to promote CSC maintenance and malignant transformation. However, the role of MELK in TNBC metastasis is unknown; we sought to address this in the current study. We found that MELK mRNA levels were higher in TNBC tumors [8.11 (3.79-10.95)] than in HR+HER2- tumors [6.54 (2.90-9.26)]; P < 0.001]. In univariate analysis, patients with breast cancer with high-MELK-expressing tumors had worse overall survival (P < 0.001) and distant metastasis-free survival (P < 0.01) than patients with low-MELK-expressing tumors. In a multicovariate Cox regression model, high MELK expression was associated with shorter overall survival after adjusting for other baseline risk factors. MELK knockdown using siRNA or MELK inhibition using the MELK inhibitor MELK-In-17 significantly reduced invasiveness, reversed epithelial-to-mesenchymal transition, and reduced CSC self-renewal and maintenance in TNBC cells. Nude mice injected with CRISPR MELK-knockout MDA-MB-231 cells exhibited suppression of lung metastasis and improved overall survival compared with mice injected with control cells (P < 0.05). Furthermore, MELK-In-17 suppressed 4T1 tumor growth in syngeneic BALB/c mice (P < 0.001). Our findings indicate that MELK supports metastasis by promoting epithelial-to-mesenchymal transition and the CSC phenotype in TNBC. Significance: These findings indicate that MELK is a driver of aggressiveness and metastasis in TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/genética , Camundongos Nus , Zíper de Leucina , Proliferação de Células/fisiologia , Recidiva Local de Neoplasia , Proteínas Serina-Treonina Quinases/genética
18.
BMB Rep ; 55(5): 220-225, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35168698

RESUMO

Hepatocellular carcinoma (HCC), a primary type of liver cancer, is one of the leading causes of cancer related deaths worldwide. HCC patients have poor prognosis due to intrahepatic and extrahepatic metastasis. Hepatitis B virus (HBV) infection is one of the major causes of various liver diseases including HCC. Among HBV gene products, HBV X protein (HBx) plays an important role in the development and metastasis of HCC. However, the mechanism of HCC metastasis induced by HBx has not been elucidated yet. In this study, for the first time, we report that HBx interacts with the suppressor of cytokine signaling 1 (SOCS1) which negatively controls NF-κB by degrading p65, a subunit of NF-κB. NF-κB activates the transcription of factors associated with epithelial-mesenchymal transition (EMT), a crucial cellular process associated with invasiveness and migration of cancer cells. Here, we report that HBx physically binds to SOCS1, subsequently prevents the ubiquitination of p65, activates the transcription of EMT transcription factors and enhance cell migration and invasiveness, suggesting a new mechanism of HBV-associated HCC metastasis. [BMB Reports 2022; 55(5): 220-225].


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , NF-kappa B/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Transativadores , Proteínas Virais Reguladoras e Acessórias
19.
RSC Adv ; 12(5): 3055-3061, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35425295

RESUMO

In this study, we demonstrated poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) as a composite with Ag nanowire (Ag NW) to enhance the stretchability of the Ag NW network electrode. The composite Ag NW/PEDOT:PSS hybrid ink (AP ink) was prepared at a ratio of 1 : 10, 1 : 20, and 1 : 30, respectively and bar coated on polyurethane substrate. The different ink ratios were studied and optimized with a sheet resistance of 14.93 Ω sq-1. and a transmittance of 88.6% showing a high performance in mechanical stress tests such as bending, folding, rolling, twisting, and stretching. It also showed a conductive bridge effect where the PEDOT:PSS acted as an anchor or support to Ag NW during mechanical strain and PEDOT:PSS also enhanced the electrical conductivity of the Ag NW. Therefore, to prove the real time performance of the electrode as a wearable device, we fabricated transparent electroluminescence devices and thin film heater devices which are highly flexible and demonstrated excellent performance proving that the AP electrode is more suitable candidate for future wearable transparent devices.

20.
Nat Commun ; 13(1): 1203, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260549

RESUMO

Present-day Tibetans have adapted both genetically and culturally to the high altitude environment of the Tibetan Plateau, but fundamental questions about their origins remain unanswered. Recent archaeological and genetic research suggests the presence of an early population on the Plateau within the past 40 thousand years, followed by the arrival of subsequent groups within the past 10 thousand years. Here, we obtain new genome-wide data for 33 ancient individuals from high elevation sites on the southern fringe of the Tibetan Plateau in Nepal, who we show are most closely related to present-day Tibetans. They derive most of their ancestry from groups related to Late Neolithic populations at the northeastern edge of the Tibetan Plateau but also harbor a minor genetic component from a distinct and deep Paleolithic Eurasian ancestry. In contrast to their Tibetan neighbors, present-day non-Tibetan Tibeto-Burman speakers living at mid-elevations along the southern and eastern margins of the Plateau form a genetic cline that reflects a distinct genetic history. Finally, a comparison between ancient and present-day highlanders confirms ongoing positive selection of high altitude adaptive alleles.


Assuntos
Adaptação Fisiológica , Genoma , Adaptação Fisiológica/genética , Altitude , História Antiga , Humanos , Nepal , Tibet
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