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1.
ACS Appl Mater Interfaces ; 16(24): 31776-31787, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38858834

RESUMO

Stimuli-responsive materials have garnered substantial interest in recent years, particularly liquid crystal networks (LCNs) with sophisticatedly designed structures and morphing capabilities. Extensive efforts have been devoted to LCN structural designs spanning from two-dimensional (2D) to three-dimensional (3D) configurations and their intricate morphing behaviors through designed alignment. However, achieving microscale structures and large-area preparation necessitates the development of novel techniques capable of facilely fabricating LCN microstructures with precise control over both overall shape and alignment, enabling a 3D-to-3D shape change. Herein, a simple and cost-effective in-cell soft lithography (ICSL) technique is proposed to create LCN microstructures with customized shapes and predesigned morphing. The ICSL technique involves two sequential steps: fabricating the desired microstructure as the template by using the photopolymerization-induced phase separation (PIPS) method and reproducing the LCN microstructures through templating. Meanwhile, surface anchoring is employed to design and achieve molecular alignment, accommodating different deformation modes. With the proposed ICSL technique, cylindrical and spherical microlens arrays (CMLAs and SMLAs) have been successfully fabricated with stimulus-driven polarization-dependent focusing effects. This technique offers distinct advantages including high customizability, large-area production, and cost-effectiveness, which pave a new avenue for extensive applications in different fields, exemplified by adaptive soft micro-optics and photonics.

2.
Heliyon ; 10(4): e25861, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384504

RESUMO

Objective: Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disease associated with a high incidence of complications in the mid and late stages of gestation. This study investigates differences in the composition of intestinal flora among pregnant women diagnosed with ICP, employing Illumina MiSeq high-throughput sequencing technology. Methods: This case-control study obtained patient data from the hospital information system (HIS) and the laboratory information system (LIS). Fecal samples were collected from 25 pregnant women who did not undergo intestinal preparation before delivery between December 2020 and March 2021. Whole-genome analysis was performed. PCR was used to amplify the 16S rRNA V3-V4 variable region, which was then sequenced. Alpha and beta diversity were computed, and the maternal intestinal flora's abundance and composition characteristics were analyzed. Differences in intestinal flora between the two sample groups were examined. Results: Bacteroides and Proteobacteria exhibited positive correlations with TBIL and IBIL. Betaproteobacteria, Gammaproteobacteria, and Erysipeiotrichi showed positive correlations with TBIL, IBIL, and DBIL, while Lactobacillus, Delftia, and Odoribacter demonstrated positive correlations with ALT. Conclusion: The ICP group displayed significantly higher levels of total bile acid and ALT compared to the control group. The intestinal flora composition comprised four primary phyla: Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria. ICP patients exhibited a lower relative abundance of intestinal flora across different levels of community composition when compared to the control group. Specific correlations between certain intestinal flora and clinical liver parameters were identified.

3.
iScience ; 26(2): 106006, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36798432

RESUMO

Diaphanosoma dubium Manuilova, 1964, is a widespread planktonic water flea in Asian freshwater. Although sharing similar ecological roles with species of Daphnia, studies on D. dubium and its congeners are still few and lacking a genome for the further studies. Here, we assembled a high quality and chromosome level genome of D. dubium by combining long reads sequencing and Hi-C technologies. The total length of assembled genome was 101.8 Mb, with 98.92 Mb (97.2%) anchored into 22 chromosomes. Through comparative genomic analysis, we found the genes, involved in anti-ROS, detoxification, protein digestion, germ cells regulation and protection, underwent expansion in D. dubium. These genes and their expansion helpfully explain its widespread geographical distribution and dominance in eutrophic waters. This study provides insight into the adaptive evolution of D. dubium at genomic perspectives, and the present high quality genomic resource will be a footstone for future omics studies of the species and its congeners.

4.
J Colloid Interface Sci ; 631(Pt B): 1-7, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36379111

RESUMO

Stretchable lithium-ion batteries (SLIBs) hold great potential as a power source for wearable electronics. A major challenge in the development of SLIBs is fabricating stable and reliable stretchable electrodes. Herein, we develop a novel laser-structured microarray electrodes based SLIBs. An active material film adhered to a planar stretchable current collector is ablated by ultrafast laser into an independent microscale square array, enabling electrodes stretchable. A one-dimensional elastic analytical model is developed to evaluate the stretchability of the microarray electrodes under tensile conditions. The microscale square array adheres to the current collector and keeps intact if the shear stress is less than the adhesion force as well as the tensile stress is less than the tensile strength of the active material. The demonstrated electrodes have a mass active material loading of 10 mg cm-2 and maintain robust electrochemical performance when stretched beyond 500 cycles at 100 % strains. The fabricated SLIBs show a stable capacity of 1.2 mAh cm-2, and over 70 % of initial capacity can be maintained at 100 % strain.

5.
Opt Express ; 30(25): 44665-44680, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522887

RESUMO

In this study, we propose a polarization-modulated laser-induced microjet-assisted ablation method for machining microgrooves with controllable cross-sections. A novel mathematical model is presented to accurately predict the cross-sections by considering the combined effects of polarization and secondary ablation. The simulation and experimental results reveal that the effect of secondary ablation becomes more obvious when steeper grooves are ablated with higher repetition frequency and larger pulse energy. The polarization effect and secondary ablation of target material result in asymmetric ablation of linearly polarized laser beam. To avoid the asymmetric ablation, we present the cylindrical vector beams to achieve scanning-path independent laser micromachining with various cross-sections. Based on the prediction model, the cross-sectional characteristics are precisely designed and fabricated by tuning laser processing parameters. Our work provides a reliable approach for the controllable fabrication of microgrooves at the scale of tens of micrometers.

6.
Nat Commun ; 13(1): 5823, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192549

RESUMO

Rigorously designed sub-micrometer structure arrays are widely used in metasurfaces for light modulation. One of the glaring restrictions is the unavailability of easily accessible fabrication methods to efficiently produce large-area and freely designed structure arrays with nanoscale resolution. We develop a patterned pulse laser lithography (PPLL) approach to create structure arrays with sub-wavelength feature resolution and periods from less than 1 µm to over 15 µm on large-area thin films with substrates under ambient conditions. Separated ultrafast laser pulses with patterned wavefront by quasi-binary phase masks rapidly create periodic ablated/modified structures by high-speed scanning. The gradient intensity boundary and circular polarization of the wavefront weaken diffraction and polarization-dependent asymmetricity effects during light propagation for high uniformity. Structural units of metasurfaces are obtained on metal and inorganic photoresist films, such as antennas, catenaries, and nanogratings. We demonstrate a large-area metasurface (10 × 10 mm2) revealing excellent infrared absorption (3-7 µm), which comprises 250,000 concentric rings and takes only 5 minutes to produce.

7.
ACS Appl Mater Interfaces ; 14(41): 47237-47245, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36200938

RESUMO

Optical antireflection surfaces equipped with subwavelength nanocone arrays are commonly used to reach broadband supertransmissivity but are limited by the lack of wear resistance. We design and manufacture a structured surface with robust antireflection structures (R-ARS) composed of substrate-engraved nanocone arrays with micro-grid-shaped walls as protective armor. An ultrafast laser beam is used to selectively ablate and dope the metal from the deposited film into the subsurface of optical substrates to strengthen self-assembled nanoparticles formed during plasma etching as masks for nanocones. The untreated microscale metal grids serve as etching masks for the remaining protective armor. The geometrical features of nanocones and spatial distribution of protective armor with a proper duty cycle are theoretically optimized for improvement in both transmissivity and mechanical robustness. We demonstrate armored dense engraved nanocone arrays (with tip diameters of ∼50 nm and heights of ∼0.8 µm) on visible fused silica and infrared semi-insulating SiC with protective micro-square-grid armor. The average transmittances are improved from 93% to over 97% (on 0.4-1.2 µm) for double-face-structured fused silica, and from 60 to 65% (on 3-5 µm) for single-face-structured SiC, with few reductions of fused silica after 150 cycles of severe abrasion (under a pressure of 5.34 MPa) proving the excellent mechanical robust performance of R-ARS.

8.
ACS Appl Mater Interfaces ; 14(42): 48276-48284, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36228148

RESUMO

Flexible multidirectional strain sensors capable of simultaneously detecting strain amplitudes and directions have attracted tremendous interest. Herein, we propose a flexible multidirectional strain sensor based on a newly designed single-layer hierarchical aligned micro-/nanowire (HAMN) network. The HAMN network is efficiently fabricated using a one-step femtosecond laser patterning technology based on a modulated line-shaped beam. The anisotropic performance is attributed to the significantly different morphological changes caused by an inhomogeneous strain redistribution among the HAMN network. The fabricated strain sensor exhibits high sensitivity (gauge factor of 65 under 2.5% strain and 462 under larger strains), low response/recovery time (140 and 322 ms), and good stability (over 1000 cycles). Moreover, this single-layer strain sensor with high selectivity (gauge factor differences of ∼73 between orthogonal strains) is capable of distinguishing multidimensional strains and exhibits decoupled responses under low strains (<1%). Therefore, the strain sensors enable the precise monitoring of subtle movements, including radial pulses and wrist bending, and the rectification of pen-holding posture. Benefitting from these remarkable performances, the HAMN-based strain sensors show potential applications, including healthcare and complex human motion monitoring.

9.
Invest New Drugs ; 40(6): 1206-1215, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36063263

RESUMO

Dual mTORC1/2 inhibitors may be more effective than mTORC1 inhibitor rapamycin. Nevertheless, their metabolic effects on breast cancer cells have not been reported. We compared the anti-proliferative capacity of rapamycin and a novel mTORC1/2 dual inhibitor (AZD8055) in two breast cancer cell lines (MDA-MB-231 and MDA-MB-453) and analyzed their metabolic effects using proton nuclear magnetic resonance (1H NMR) spectroscopy-based metabolomics. We found that AZD8055 more strongly inhibited breast cancer cell proliferation than rapamycin. The half-inhibitory concentration of AZD8055 in breast cancer cells was almost one-tenth that of rapamycin. We identified 22 and 23 metabolites from the 1H NMR spectra of MDA-MB-231 and MDA-MB-453 cells. The patterns of AZD8055- and rapamycin-treated breast cancer cells differed significantly; we then selected the metabolites that contributed to these differences. For inhibiting glycolysis and reducing glucose consumption, AZD8055 was likely to be more potent than rapamycin. For amino acids metabolism, although AZD8055 has a broad effect as rapamycin, their effects in degrees were not exactly the same. AZD8055 and rapamycin displayed cell-specific metabolic effects on breast cancer cells, a finding that deserves further study. These findings help fill the knowledge gap concerning dual mTORC1/2 inhibitors and provide a theoretical basis for their development.


Assuntos
Neoplasias da Mama , Sirolimo , Humanos , Feminino , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Prótons , Serina-Treonina Quinases TOR/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Neoplasias da Mama/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Proliferação de Células
10.
Nano Lett ; 22(15): 6223-6228, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35849492

RESUMO

This paper proposes a one-step maskless 2D nanopatterning approach named self-aligned plasmonic lithography (SPL) by line-shaped ultrafast laser ablation under atmospheric conditions for the first time. Through a theoretical calculation of electric field and experimental verification, we proved that homogeneous interference of laser-excited surface plasmon polaritons (SPPs) can be achieved and used to generate long-range ordered 2D nanostructures in a self-aligned way over a wafer-sized area within several minutes. Moreover, the self-aligned nanostructures can be freely transferred between embossed nanopillars and engraved nanoholes by modulating the excitation intensity of SPPs interference through altering the incident laser energy. The SPL technique exhibits further controllability in the shape, orientation, and period of achievable nanopatterns on a wide range of semiconductors and metals by tuning processing parameters. Nanopatterned films can further act as masks to transfer structures into other bulk materials, as demonstrated in silica.

11.
J Cell Mol Med ; 26(16): 4492-4505, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35855570

RESUMO

Crizotinib (CRIZO) has been widely employed to treat non-small-cell lung cancer. However, hepatic inflammatory injury is the major toxicity of CRIZO, which limits its clinical application, and the underlying mechanism of CRIZO-induced hepatotoxicity has not been fully explored. Herein, we used cell counting kit-8 assay and flow cytometry to detect CRIZO-induced cytotoxicity on human hepatocytes (HL-7702). CRIZO significantly reduced the survival rate of hepatocytes in a dose-dependent manner. Furthermore, the reactive oxygen species (ROS) assay kit showed that CRIZO treatment strongly increased the level of ROS. In addition, CRIZO treatment caused the appearance of balloon-like bubbles and autophagosomes in HL-7702 cells. Subsequently, Western blotting, quantitative real-time PCR and ELISA assays revealed that ROS-mediated pyroptosis and autophagy contributed to CRIZO-induced hepatic injury. Based on the role of ROS in CRIZO-induced hepatotoxicity, magnesium isoglycyrrhizinate (MgIG) was used as an intervention drug. MgIG activated the Nrf2/HO-1 signalling pathway and reduced ROS level. Additionally, MgIG suppressed hepatic inflammation by inhibiting NF-κB activity, thereby reducing CRIZO-induced hepatotoxicity. In conclusion, CRIZO promoted autophagy activation and pyroptosis via the accumulation of ROS in HL-7702 cells. MgIG exerts therapeutic effects on CRIZO-induced hepatotoxicity by decreasing the level of ROS.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Doença Hepática Induzida por Substâncias e Drogas , Neoplasias Pulmonares , Autofagia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Crizotinibe/farmacologia , Humanos , Piroptose , Espécies Reativas de Oxigênio/metabolismo , Saponinas , Triterpenos
12.
Front Genet ; 12: 711992, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531896

RESUMO

Phyllodiaptomus tunguidus (Copepoda: Calanoida) is largely endemic to and widespread in freshwater in southern China, where it inhabits a complex landscape from lowland to highland across an elevation gradient of 2000m. A deep genetic differentiation can be expected between its most distant geographic populations. Here, we sequenced nine mitogenomes from diverse populations. All mitogenomes contained 37 genes, including 13 protein-coding genes (PCG), two rRNA genes, 22 tRNA genes and one control region. Their base composition, genetic distance and tRNA structure indeed revealed a wide differentiation between mitogenomes. Two P. tunguidus from Guangxi near Vietnam differed from the other seven by up to 10.1%. Their tRNA-Arg had a complete clover-leaf structure, whereas that of the others did not contain an entire dihydrouridine arm. The nine mitogenomes also differed in the length of rRNA. NJ, ML, and Bayesian analyses all split them into two clades, viz. the two P. tunguidus from Guangxi (Clade 1), and the other seven (Clade 2). Both the structure and phylogeny of the mitogenomes suggest that P. tunguidus has complex geographic origin, and its populations in Clade 1 have long lived in isolation from those in Clade 2. They currently reach the level of subspecies or cryptic species. An extensive phylogenetic analysis of Copepoda further verified that Diaptomidae is the most recently diverging family in Calanoida and that P. tunguidus is at the evolutionary apex of the family.

13.
Mol Phylogenet Evol ; 164: 107275, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34339827

RESUMO

Cladocera (Crustacea: Branchiopoda) is a key group of invertebrates. Despite a long history of phylogenetic research, relationships within this group remain disputed. We here provide new insights based on 15 new mitochondrial genomes obtained from high-throughput sequencing (HTS) and 40 mitogenomes extracted from published HTS datasets. Together with 25 mitogenomes from GenBank, we generated a matrix of 80 mitogenomes, 44 of them belonging to Cladocera. We also obtained a matrix with 168 nuclear orthologous genes to further assess the phylogenetic result from mitogenomes based on published data and one new HTS data ofLeptodora. Maximum likelihood and Bayesian phylogenetic analyses recovered all Branchiopoda orders as monophyletic and supported a sister-group relationship between Anomopoda and Onychopoda, making the taxon Gymnomera paraphyletic and supporting an independent origin of predatory Haplopoda and Onychopoda. The nuclear phylogeny and topological tests also support Gymnomera as paraphyletic, and the nuclear phylogeny strongly supports a sister-group relationship between Ctenopoda and Haplopoda. We provide a fossil-calibrated time tree, congruent with a Carboniferous origin for Cladocera and a subsequent diversification of the crown group of Anomopoda, Onychopoda, and Ctenopoda, at least in the Triassic. Despite their long evolutionary history, non-Cladoceran Branchiopoda exhibited high mitogenome structural stability. On the other hand, 21 out of 24 gene rearrangements occurred within the relatively younger Cladocera. We found the differential base compositional skewness patterns between Daphnia s.s. and Ctenodaphnia, which might be related to the divergence between these taxa. We also provide evidence to support the recent finding that Spinicaudata possesses mitogenomes with inversed compositional skewness without gene rearrangement. Such a pattern has only been reported in Spinicaudata.


Assuntos
Cladocera , Genoma Mitocondrial , Animais , Teorema de Bayes , Ordem dos Genes , Rearranjo Gênico , Filogenia , Comportamento Predatório
14.
Mitochondrial DNA B Resour ; 6(2): 636-640, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33659709

RESUMO

Rotifers are a small-sized but key group of freshwater zooplankters with high species richness, linking primary producers to higher consumers in aquatic food webs. DNA barcoding has been widely used in exploring its biodiversity, cryptic speciation and phylogeny. However, the inefficiency of universal primers to amplify COI of rotifers hinders our understanding of their species richness and genetic diversity. Here, we develop a new pair of primers, 30 F and 885 R, to amplify the COI gene of rotifers. We used 22 species to test their PCR success rate and found that the new pair of primers was more efficient (86%) than two pairs of universal primers, namely, dgLCO and dgHCO (32%), and Folmer primers (59%). The new primers will allow the barcoding of groups that were so far difficult to sequence and will contribute to clarify species diversity and phylogeny of rotifers.

15.
Ann Clin Microbiol Antimicrob ; 20(1): 4, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407509

RESUMO

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae) is one of the most common pathogens which can cause morbidity and mortality in pediatric infections worldwide. This study aimed to describe the phenotypic and molecular characteristics of community-acquired pneumonia (CAP)-causing S. pneumoniae recovered from children in Western China. METHODS: We retrospectively enrolled pediatric patients younger than 5 years diagnosed with CAP. All 419 S. pneumoniae isolates were tested for antibiotic susceptibility, serotypes, virulence genes, resistance genes, and sequence types. The potential relationships between molecular characteristics were tested by correspondence analysis. RESULTS: Most of S. pneumoniae isolates were resistant to erythromycin, tetracycline, clindamycin and trimethoprim-sulfamethoxazole, with 93.8% isolates classified as multidrug resistant. The dominant STs were ST271 (30.8%) and ST320 (12.2%), while the prevailing serotypes were 19F (46.8%), 6B (11.5%), 23F (9.5%) and 19A (9.3%). The coverage rates of PCV-7 and PCV-13 were 73.03% and 86.16%, while the coverage rates of PCV13 among children aged < 1 year and 1-2 years were high in 93.18% and 93.62%. We also observed that CC271 expressed more of mef (A/E), lytA, rlrA and sipA than non-CC271 isolates. Moreover, there were strong corresponding relationships between molecular characteristics. CONCLUSIONS: The high coverage rate of PCV13 suggests the necessity of introducing the PCV13 vaccine in Western China. Our findings underscore the value of monitoring multiple molecular characteristics to provide new guidance for developing future pneumococcal vaccines.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Pneumonia Pneumocócica/epidemiologia , Streptococcus pneumoniae/genética , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Vacinas Pneumocócicas/imunologia , Pneumonia Pneumocócica/microbiologia , Estudos Retrospectivos , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação
16.
Mitochondrial DNA B Resour ; 5(3): 2521-2522, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-33457849

RESUMO

The mitochondrial genome of Phyllodiaptomus diaptomus was sequenced and assembled via Next-Generation Sequencing (NGS) and iterative assembly with a reference seed. The genome is 16446 bp long, A + T biased (69.4%), with 13 protein-coding genes, 22 tRNAs, and 2 rRNA. All protein-coding genes are initiated by a typical "ATN" codon. ND1, ND2, ATP6 genes are terminated with "TAG", the other 10 genes are terminated with "TAA". This is the first complete mitogenome published in the Diaptomidae. It provides molecular information useful to a better understanding of the phylogeny of calanoids.

17.
BMC Pediatr ; 19(1): 424, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711442

RESUMO

BACKGROUND: To summarize information about invasive pneumococcal disease (IPD) among children in mainland China. METHODS: Sixteen eligible studies were included in this systematic review and the random effect model was used to estimate the pool prevalence of IPD. RESULTS: The most predominant serotypes circulating in children were 19F (27.7, 95% confidence interval (95% CI): 17.7-37.6%), 19A (21.2%, 16.4-26.1%), 14 (16.5%, 12.8-20.1%), 6B (8.6%, 5.2-10.8%) and 23F (7.3%, 5.2-9.5%). The serotype coverage of the available pneumococcal conjugate vaccines PCV7, PCV10, and PCV13 was 60.8% (52.5-69.4%), 65.1% (57.7-72.4%), and 90.0% (87.1-92.8%), respectively. The pooled antibiotic resistance rates of Streptococcus pneumoniae revealed a resistance to penicillin prevalence rate of 32.0% (12.1-51.9%). Approximately 94.4% (90.7-98.1%) and 92.3% (87.4-97.3%) of isolates were resistant to erythromycin and clindamycin. eBURST analysis revealed great diversity among isolates, with 102 sequence types (STs) for 365 isolates. The major predominant clonal complexes (CCs) were CC271 (43.6%, 159/365), CC876 (13.4%, 49/365), CC81 (5.2%, 19/365), and CC90 (4.1%, 15/365). Long-term and regional surveillance of S. pneumoniae is necessary. CONCLUSIONS: Based on our pooled results showing that PCV13 coverage of the reported serotypes was 90% and that most serotypes contributed to the distribution of antibiotic-resistant isolates, implementation of PCV13 into the Chinese Expanded Program on Immunizations (EPI) would achieve health benefits in Chinese children.


Assuntos
Farmacorresistência Bacteriana , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/genética , Criança , China/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas , Prevalência , Sorotipagem , Streptococcus pneumoniae/efeitos dos fármacos , Vacinas Conjugadas
18.
Nanoscale Res Lett ; 14(1): 309, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31502007

RESUMO

As an important third-generation semiconductor material, the micro-deformation and removal mechanism of 6H-SiC at the atomic scale are vital for obtaining ultra-smooth and damage-free surface with atomic steps. Due to the difficulties in directly observing the surface/subsurface of nanomachining region by current experimental means, molecular dynamics method is used to study the atomic-scale details in nanomachining process, such as dislocation slip motion, phase transition, and material separation mechanism. The influence of crystallography-induced anisotropy on the slip deformation and nanometric machinability of 6H-SiC is emphatically investigated. This study contributes significantly to the understanding of micro-deformation and nanomachining process of 6H-SiC.

19.
Cell Death Dis ; 10(6): 465, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197130

RESUMO

An increasing interest in liver cancer stemness arises owing to its aggressive behavior and poor prognosis. CD133, a widely known liver cancer stem cell marker, plays critical roles in the maintenance of liver cancer stemness. Thus, exploring the regulatory mechanism of CD133 expression is significant. In the present study, we proved the carcinogenesis roles of aquaporin 3 (AQP3) in hepatocellular carcinoma (HCC) and demonstrated that AQP3 promotes the stem cell-like properties of hepatoma cells by regulating CD133 expression. In addition, AQP3 promoted the stimulation and nuclear translocation of signal transducer and activator of transcription 3 (STAT3) with a subsequent increase in the level of CD133 promoter-acetylated histone H3. This phenomenon accelerated CD133 transcription. Next, whether AQP3 acted as an oncogenic gene in HCC and maintained the stemness of CD133+ hepatoma cells were elucidated; also, a novel mechanism underlying the AQP3/STAT3/CD133 pathway in HCC was deduced.


Assuntos
Antígeno AC133/metabolismo , Aquaporina 3/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/metabolismo , Antígeno AC133/genética , Animais , Aquaporina 3/genética , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Histonas/química , Histonas/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética
20.
Mol Med Rep ; 19(6): 4998-5006, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059022

RESUMO

Emerging evidence suggests that long noncoding RNAs (lncRNAs) serve a key role in malignant transformation, tumor progression and metastasis. Increased expression of lncRNA p53 upregulated regulator of P53 levels (PURPL) has been reported to promote tumorigenicity in colorectal cancer; however, the role and potential mechanisms of PURPL in the development of liver cancer remain unclear. We employed reverse transcription­quantitative polymerase chain reaction to detect PURPL and p53 mRNA expression in liver cancer tissues and cell lines. Cell Counting Kit­8 and colony­forming assays were used to examine the cell proliferation; whereas, flow cytometry was applied to detect apoptosis and cell cycle progression. p53 expression was detected by western blotting. The results revealed that PURPL was significantly upregulated in liver cancer tissues compared with in paracancerous tissues, and was associated with tumor differentiation stage and tumor size. PURPL was also upregulated in various liver cancer cell lines. Silencing of PURPL inhibited liver cancer cells proliferation, blocked cell cycle progression, and promoted apoptosis. Most importantly, PURPL expression was negatively correlated with p53 mRNA expression. In summary, lncRNA­PURPL was proposed to promote cell proliferation in liver cancer by regulating the p53 gene. As such, it could serve as a potential therapeutic target for the diagnosis and treatment of liver cancer.


Assuntos
Proliferação de Células , Neoplasias Hepáticas/patologia , RNA Longo não Codificante/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno , Proteína Supressora de Tumor p53/genética
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