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1.
J Am Chem Soc ; 146(33): 23252-23264, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39120959

RESUMO

Janus monolayers of transition metal dichalcogenides (TMDs) offer versatile applications due to their tunable polymorphisms. While previous studies focused on conventional 2H-phase Janus monolayers, the scalable synthesis of an unconventional 1T' phase remains challenging. We present a novel solution strategy for fabricating Janus 1T'-MoOSe and MoSSe monolayers by growing sandwiched Se-Mo-O/S shells onto Au nanocores. The Janus Au@1T'-MoSSe catalyst exhibits superior electrocatalytic hydrogen evolution reaction (HER) activity compared to 1T'-MoS2, -MoSe2, and -MoOSe, attributed to its unique electronic structure and intrinsic strain. Remarkably, photoexciting the nanoplasmonic Au cores further enhances the HER via a localized surface plasmon (LSP) effect that drives hot electron injection into surface sulfur vacancies of 1T'-MoSSe monolayer shells, accelerating proton reduction. This synergistic activation of anion vacancies by internal strain and external light-induced Au LSPs, coupled with our scalable synthesis, provides a pathway for developing tailorable polymorphic Janus TMDs for specific applications.

2.
FASEB J ; 37(9): e23111, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37531300

RESUMO

The post-transfer developmental capacity of bovine somatic cell nuclear transfer (SCNT) blastocysts is reduced, implying that abnormalities in gene expression regulation are present at blastocyst stage. Chromatin accessibility, as an indicator for transcriptional regulatory elements mediating gene transcription activity, has heretofore been largely unexplored in SCNT embryos, especially at blastocyst stage. In the present study, single-cell sequencing assay for transposase-accessible chromatin (scATAC-seq) of in vivo and SCNT blastocysts were conducted to segregate lineages and demonstrate the aberrant chromatin accessibility of transcription factors (TFs) related to inner cell mass (ICM) development in SCNT blastocysts. Pseudotime analysis of lineage segregation further reflected dysregulated chromatin accessibility dynamics of TFs in the ICM of SCNT blastocysts compared to their in vivo counterparts. ATAC- and ChIP-seq results of SCNT donor cells revealed that the aberrant chromatin accessibility in the ICM of SCNT blastocysts was due to the persistence of chromatin accessibility memory at corresponding loci in the donor cells, with strong enrichment of trimethylation of histone H3 at lysine 4 (H3K4me3) at these loci. Correction of the aberrant chromatin accessibility through demethylation of H3K4me3 by KDM5B diminished the expression of related genes (e.g., BCL11B) and significantly improved the ICM proliferation in SCNT blastocysts. This effect was confirmed by knocking down BCL11B in SCNT embryos to down-regulate p21 and alleviate the inhibition of ICM proliferation. These findings expand our understanding of the chromatin accessibility abnormalities in SCNT blastocysts and BCL11B may be a potential target to improve SCNT efficiency.


Assuntos
Cromatina , Técnicas de Transferência Nuclear , Animais , Bovinos , Cromatina/genética , Cromatina/metabolismo , Blastocisto/metabolismo , Desenvolvimento Embrionário/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
3.
Clin Exp Hypertens ; 46(1): 2390419, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39133866

RESUMO

BACKGROUND: Complex interconnections are evident among gut microbiota, circulating metabolites, inflammatory cytokines, and the pathogenesis of abdominal aortic aneurysms (AAA), with the causal dynamics yet to be comprehensively elucidated. The primary objective of this study was to elucidate the potential causal relationships involving gut microbiota-mediated plasma metabolites, inflammatory cytokines, and AAA. METHODS: We utilized data from genome-wide association studies predominantly comprising individuals of European ancestry, encompassing four major gut microbiota signatures, 233 plasma metabolite signatures (N = 136,016), 91 inflammatory cytokine signatures (N = 14,824), and AAA signatures (N = 1,458,875). Mendelian randomization (MR), employed in a two-sample format, was utilized as a tool to investigate the potential causal pathways from gut microbiota to the development of AAA. Additionally, a two-step MR approach was employed to dissect the impact of plasma metabolites and inflammatory cytokines on the relationship between gut microbiota and AAA and to ascertain the mediated fractions. RESULTS: Our findings indicate that five phylum or family-identical bacteria, 175 plasma metabolites, and seven inflammatory factors are causally associated with AAA. Among them, five bacterial species from the same phylum or family, identified from different GWAS data, were strongly associated with AAA. Of these, two exhibited negative causality and three exhibited positive causality. We found that the phylum Firmicutes and the families Oscillospiraceae might reduce the risk of AAA, whereas the families Prevotellaceae, Sutterellaceae, and Aminobacteriaceae might increase the risk of AAA. Further screening indicated that phylum Firmicutes id.1672 (GCST90017114) may confer a protective effect against AAA by reducing triglyceride levels in medium/small high-density lipoprotein (HDL). CONCLUSION: MR analysis has delineated a causal pathway from gut microbiota, through plasma circulating metabolites and inflammatory cytokines, to the pathogenesis of AAA. The role of intestinal flora and certain biomarkers may provide a reference for the diagnosis of AAA, and contribute to the prevention, diagnosis, and treatment of AAA disease.


Assuntos
Aneurisma da Aorta Abdominal , Citocinas , Microbioma Gastrointestinal , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Aneurisma da Aorta Abdominal/microbiologia , Aneurisma da Aorta Abdominal/sangue , Aneurisma da Aorta Abdominal/genética , Humanos , Microbioma Gastrointestinal/fisiologia , Microbioma Gastrointestinal/genética , Citocinas/sangue , Masculino , Feminino , Inflamação/sangue , Inflamação/genética
4.
Angew Chem Int Ed Engl ; : e202414701, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39275887

RESUMO

Unconventional 1T' phase transition metal dichalcogenides (TMDs) show great potential for hydrogen evolution reaction (HER). However, they are susceptible to transitioning into the stable 2H phase, which reduces their catalytic activity and stability. Herein, we present a scalable approach for designing thermally stable 1T'-TMDs hollow structures (HSs) by etching Cu1.94S templates from pre-synthesized Cu1.94S@TMDs heterostructures, including 1T'-MoS2, MoSe2, WS2, and WSe2 HSs. Furthermore, taking 1T'-MoS2 HSs as an example, the etched Cu ions can be firmly adsorbed on their surface in the form of single atoms (SAs) through Cu-S bonds, thereby elevating the phase transition temperature from 149 ºC to 373 ºC. Due to the advantages conferred by the 1T' phase, hollow structure, and synergistic effect between Cu SAs and 1T'-MoS2 supports, the fabricated 1T'-MoS2 HSs demonstrate superior HER performance. Notably, their high-phase stability enables continuous operation of designed 1T'-MoS2 HSs for up to 200 hours at an ampere-level current density without significant activity decay. This work provides a universal method for synthesizing highly stable 1T'-TMDs electrocatalysts, with a particular focus on the relationship between their phase and catalytic stability.

5.
Angew Chem Int Ed Engl ; : e202413173, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39344804

RESUMO

Vanadium (V)-based oxides as cathode materials for aqueous zinc-ion batteries (AZIBs) still encounter challenges such as sluggish Zn2+ diffusion kinetics and V-dissolution, thus leading to severe capacity fading and limited life span. Here, we designed an ultrafast and facile colloidal chemical synthesis strategy based on crystalline Zn0.25V2O5 (c-ZVO) to successfully prepare a-ZVO@MoS2 core@shell heterostructures, where atomic-layer MoS2 uniformly coats on the surface of amorphous a-ZVO. The tailored amorphous structure of a-ZVO provides more isotropic pathways and active sites for Zn2+, thus significantly enhancing the Zn2+ diffusion kinetics during charge-discharge processes. Meanwhile, as an efficient artificial cathode electrolyte interphase, the precision-engineered atomic-layer MoS2 with semi-metallic 1T' phase not only contributes to improved electron transport but also effectively inhibits the V-dissolution of a-ZVO. Therefore, the prepared a-ZVO@MoS2 and conceptually validated a-V2O5@MoS2 derived from commercial c-V2O5 exhibit excellent cycling stability at an ultralow current density (0.05 A g-1) while maintaining good rate capability and capacity retention. This research achievement provides a new effective strategy for various amorphous cathode designs for AZIBs with superior performance.

6.
Small ; 19(46): e2303985, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37442792

RESUMO

Potassium-ion batteries (PIBs) have broad application prospects in the field of electric energy storage systems because of its abundant K reserves, and similar "rocking chair" operating principle as lithium-ion batteries (LIBs). Aiming to the large volume expansion and sluggish dynamic behavior of anode materials for storing large sized K-ion, bismuth telluride (Bi2 Te3 ) nanoplates hierarchically encapsulated by reduced graphene oxide (rGO), and nitrogen-doped carbon (NC) are constructed as anodes for PIBs. The resultant Bi2 Te3 @rGO@NC architecture features robust chemical bond of Bi─O─C, tightly physicochemical confinement effect, typical conductor property, and enhanced K-ion adsorption ability, thereby producing superior electrochemical kinetics and outstanding morphological and structural stability. It is visually elucidated via high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) that conversion-alloying dual-mechanism plays a significant role in K-ion storage, allowing 12 K-ion transport per formular unit employing Bi as redox site. Thus, the high first reversible specific capacity of 322.70 mAh g-1 at 50 mA g-1 , great rate capability and cyclic stability can be achieved for Bi2 Te3 @rGO@NC. This work lays the foundation for an in-depth understanding of conversion-alloying mechanism in potassium-ion storage.

7.
Biol Reprod ; 109(3): 282-298, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37498179

RESUMO

In vitro maturation of mammalian oocytes is an important means in assisted reproductive technology. Most bovine immature oocytes complete nuclear maturation, but less than half develop to the blastocyst stage after fertilization. Thus, inefficient in vitro production is mainly caused by a suboptimal in vitro culture process, in which oocyte quality appears to be the limiting factor. In our study, a potential maternal regulator, C-X-C motif chemokine ligand 12, was identified by analyzing transcriptome data. C-X-C motif chemokine ligand 12 supplementation promoted the developmental potential of oocytes by improving protein synthesis and reorganizing cortical granules and mitochondria during in vitro maturation, which eventually increased blastocyst formation efficiency and cell number after parthenogenesis, fertilization, and cloning. All these promoting effects by C-X-C motif chemokine ligand 12 were achieved by activating SH2 domain-containing tyrosine phosphatase 2, thereby promoting the mitogen-activated protein kinase signaling pathway. These findings provide an in vitro maturation system that closely resembles the maternal environment to provide high-quality oocytes for in vitro production.


Assuntos
Oócitos , Domínios de Homologia de src , Bovinos , Animais , Ligantes , Oócitos/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Quimiocinas/metabolismo , Tirosina/metabolismo , Técnicas de Maturação in Vitro de Oócitos/veterinária , Blastocisto/metabolismo , Fertilização in vitro , Mamíferos/metabolismo
8.
Analyst ; 148(14): 3295-3305, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37318011

RESUMO

Highly sensitive protein biomarker detection is critical for the diagnosis of gastric cancer (GC), however the accurate and sensitive detection of low-abundance proteins in early-stage GC is still a challenge. Herein, a surface-enhanced Raman scattering frequency shift assay was performed on a developed microfluidic chip for the detection of GC protein biomarkers carcinoembryonic antigen (CEA) and vascular endothelial growth factor (VEGF). The chip is made up of three groups of parallel channels and each parallel channel consists of two reaction regions, enabling the simultaneous analysis of multiple biomarkers in multiple samples. The presence of CEA and VEGF in the sample can be captured by the 4-mercaptobenzoic acid (4-MBA)-conjugated antibody functionalized gold nano-sheet (GNS-) substrate, resulting in the Raman frequency shift. As a result, a typical Raman frequency shift of 4-MBA presented a linear relationship with the concentration of CEA and VEGF. The limit of detection (LOD) of the proposed SERS microfluidic chip reaches as low as 0.38 pg mL-1 for CEA and 0.82 pg mL-1 for VEGF. During the detection process, only one step of sample addition is involved, which eliminates the multiple reaction step-induced nonspecific adsorption and significantly increases the convenience and specificity. In addition, serum samples from GC patients and healthy subjects were tested and the results were in good agreement with the current gold-standard method ELISA, suggesting the potential application of the SERS microfluidic chip in clinical settings for early diagnosis and prognosis of GC.


Assuntos
Nanopartículas Metálicas , Neoplasias Gástricas , Humanos , Biomarcadores Tumorais , Antígeno Carcinoembrionário , Fator A de Crescimento do Endotélio Vascular , Microfluídica , Neoplasias Gástricas/diagnóstico , Limite de Detecção , Análise Espectral Raman/métodos
9.
J Am Chem Soc ; 144(11): 4863-4873, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35258958

RESUMO

Phase engineering of nanomaterials provides a promising way to explore the phase-dependent physicochemical properties and various applications of nanomaterials. A general bottom-up synthesis method under mild conditions has always been challenging globally for the preparation of the semimetallic phase-transition-metal dichalcogenide (1T'-TMD) monolayers, which are pursued owing to their unique electrochemical property, unavailable in their semiconducting 2H phases. Here, we report the general scalable colloidal synthesis of nanosized 1T'-TMD monolayers, including 1T'-MoS2, 1T'-MoSe2, 1T'-WS2, and 1T'-WSe2, which are revealed to be of high phase purity. Moreover, the surfactant-reliant stacking-hinderable growth mechanism of 1T'-TMD nano-monolayers was unveiled through systematic experiments and theoretical calculations. As a proof-of-concept application, the 1T'-TMD nano-monolayers are used for electrocatalytic hydrogen production in an acidic medium. The 1T'-MoS2 nano-monolayers possess abundant in-plane electrocatalytic active sites and high conductivity, coupled with the contribution of the lattice strain, thus exhibiting excellent performance. Importantly, the catalyst shows impressive endurability in electroactivity. Our developed general scalable strategy could pave the way to extend the synthesis of other broad metastable semimetallic-phase TMDs, which offer great potential to explore novel crystal phase-dependent properties with wide application development for catalysis and beyond.

10.
Small ; 18(8): e2104296, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34873861

RESUMO

The investigation of carbonaceous-based anode materials will promote the fast application of low-cost potassium-ion batteries (PIBs). Here a nitrogen and oxygen co-doped yolk-shell carbon sphere (NO-YS-CS) is constructed as anode material for K-ion storage. The novel architecture, featuring with developed porous structure and high surface specific area, is beneficial to achieving excellent electrochemical kinetics behavior and great electrode stability from buffering the large volume expansion. Furthermore, the N/O heteroatoms co-doping can not only boost the adsorption and intercalation ability of K-ion but also increase the electron transfer capability. It is also demonstrated by experimental results and DFT calculations that K-ion insertion/extraction proceeds through both intercalation and surface capacitive adsorption mechanisms. As expected, the NO-YS-CS electrodes show high initial charge capacity of 473.7 mAh g-1 at 20 mA g-1 , ultralong cycling life over 2500 cycles with the retention of 85.8% at 500 mA g-1 , and superior rate performance (183.3 mAh g-1 at 1.0 A g-1 ). The K-ion full cell, with a high energy density of 271.4 Wh kg-1 and an excellent cyclic stability over 500 cycles, is successfully fabricated with K2 Fe[Fe(CN)6 ] cathode. This work will provide new insight on the synthesis and mechanism understanding of high-performance hard carbon anode for PIBs.

11.
Neuropediatrics ; 53(6): 436-439, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35777662

RESUMO

INTRODUCTION: Focal cortical dysplasia (FCD) is a most common cause of intractable focal epilepsy in children. Surgery is considered as a radical option for such patients with the prerequisite of lesion detection. Magnetic resonance imaging (MRI) plays a significant role in detection of FCDs in epilepsy patients; however, the detection of FCDs even in epilepsy dedicated MRI sequence shows relatively low positive rate. Last year, Middlebrooks et al introduced the novel three-dimensional Edge-Enhancing Gradient Echo (3D-EDGE) MRI sequence and using this sequence successfully identified five cases of FCDs which indicates its potential role in those epilepsy patients who may have FCDs. CASE PRESENTATION: We present a 14-year-old, right-handed, male patient who has suffered from drug-resistant epilepsy over the past 3 years. It was unable to localize the lesion of the seizure, even using the series of epilepsy dedicated MRI sequences. Inspired by the previous report, the lesion of the seizure was successfully targeted by 3D-EDGE sequence. Combined with intraoperative navigation and precisely removed the lesion. He was uneventfully recovered with no signs of cerebral dysfunction and no seizure recurrence 8 months after surgery. CONCLUSION: The 3D-EDGE sequences show a higher sensitivity for FCD detection in epilepsy patients compared with a series of epilepsy-dedicated MRI protocols. We confirmed that the study by Middlebrooks et al is of great clinical value. If the findings on routine MRI sequences or even epilepsy-dedicated MRI sequences were reported as negative, however, the semiology, video-electroencephalography, and fluorodeoxyglucose-positron emission tomography results suggest a local abnormality, and the results are concordant with each other, a 3D-EDGE sequence may be a good option.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Epilepsia , Malformações do Desenvolvimento Cortical , Criança , Humanos , Masculino , Adolescente , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/cirurgia , Malformações do Desenvolvimento Cortical/patologia , Imageamento por Ressonância Magnética/métodos , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Epilepsia/etiologia , Convulsões , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/etiologia , Epilepsia Resistente a Medicamentos/cirurgia , Estudos Retrospectivos
12.
J Vasc Res ; 58(3): 180-190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33794525

RESUMO

Hypertension is considered a risk factor for a series of systematic diseases. Known factors including genetic predisposition, age, and diet habits are strongly associated with the initiation of hypertension. The current study aimed to investigate the role of miR-22-3p in hypertension. In this study, we discovered that the miR-22-3p level was significantly decreased in the thoracic aortic vascular tissues and aortic smooth muscle cells (ASMCs) of spontaneously hypertensive rats. Functionally, the overexpression of miR-22-3p facilitated the switch of ASMCs from the synthetic to contractile phenotype. To investigate the underlying mechanism, we predicted 11 potential target mRNAs for miR-22-3p. After screening, chromodomain helicase DNA-binding 9 (CHD9) was validated to bind with miR-22-3p. Rescue assays showed that the co-overexpression of miR-22-3p and CHD9 reversed the inhibitory effect of miR-22-3p mimics on cell proliferation, migration, and oxidative stress in ASMCs. Finally, miR-22-3p suppressed vascular remodeling and oxidative stress in vivo. Overall, miR-22-3p regulated ASMC phenotype switch by targeting CHD9. This new discovery provides a potential insight into hypertension treatment.


Assuntos
Caderinas/metabolismo , Hipertensão/metabolismo , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Estresse Oxidativo , Remodelação Vascular , Animais , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Caderinas/genética , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipertensão/genética , Hipertensão/patologia , Hipertensão/fisiopatologia , MicroRNAs/genética , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/patologia , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Transdução de Sinais
13.
J Am Chem Soc ; 142(19): 8953-8961, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32307986

RESUMO

Metal-organic framework (MOF) heterostructures have shown promising applications in gas adsorption, gas separation, catalysis, and energy, arising from the synergistic effect of each component. However, owing to the difficulty in controlling the size, shape, nucleation, and growth of MOFs, it remains a great challenge to construct MOF heterostructures with precisely controlled orientation, morphology, dimensionality, and spatial distribution of each component. Here, we report a seeded epitaxial growth method to prepare a series of hierarchical MOF heterostructures by engineering the structures, sizes, dimensionalities, morphologies, and lattice parameters of both MOF seeds and the secondary MOFs. In these heterostructures, PCN-222 (also known as MOF-545) nanorods selectively grow along the major axis of the ellipsoid-like PCN-608 nanoparticles, on the two end facets of the hexagonal prism-like NU-1000 nanorods, and on the two basal planes of the hexagonal PCN-134 nanoplates, while Zr-BTB nanosheets selectively grow on the six edge facets of PCN-134 nanoplates. The selective epitaxial growth of MOFs opens the way to synthesize different hierarchical heterostructures with tunable architectures and dimensionalities, which could process various promising applications.

14.
J Am Chem Soc ; 142(15): 7161-7167, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32207969

RESUMO

Understanding the reaction mechanism for the catalytic process is essential to the rational design and synthesis of highly efficient catalysts. MoS2 has been reported to be an efficient catalyst toward the electrochemical hydrogen evolution reaction (HER), but it still lacks direct experimental evidence to reveal the mechanism for MoS2-catalyzed electrochemical HER process at the atomic level. In this work, we develop a wet-chemical synthetic method to prepare the single-layer MoS2-coated polyhedral Ag core-shell heterostructure (Ag@MoS2) with tunable sizes as efficient catalysts for the electrochemical HER. The Ag@MoS2 core-shell heterostructures are used as ideal platforms for the real-time surface-enhanced Raman spectroscopy (SERS) study owing to the strong electromagnetic field generated in the plasmonic Ag core. The in situ SERS results provide solid Raman spectroscopic evidence proving the S-H bonding formation on the MoS2 surface during the HER process, suggesting that the S atom of MoS2 is the catalytic active site for the electrochemical HER. It paves the way on the design and synthesis of heterostructures for exploring their catalytic mechanism at atomic level based on the in situ SERS measurement.

15.
Mol Hum Reprod ; 25(8): 471-482, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31041452

RESUMO

Accumulated evidence indicates that sperm-borne small RNA plays a crucial role in embryonic development, especially the absence of the sperm-borne small RNA might be a major cause of the abnormal development of cloned embryos. In this study, we found that sperm-borne small RNA can affect abnormal pronuclear-like structures, postpone the timing of first embryo cleavage and enhance developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos. In addition, the supplementation of sperm-borne small RNA can significantly increase live birth rates and decrease the birth weights of cloned offspring. To investigate the underlying mechanisms, the levels of α-tubulin K40 acetylation (Ac α-tubulin K40) and histone H3 lysine 9 trimethylation (H3K9me3) during early embryo development were investigated in SCNT embryos with sperm-borne small RNA supplementation (termed as T-NT), compared to those normal SCNT embryos and embryos obtained from standard IVF. The results showed that sperm-borne small RNA can significantly decrease the H3K9me3 levels at the pronuclear and two-cell stages, while significantly increase Ac α-tubulin K40 levels at anaphase and telophase of bovine SCNT embryos during the first cleavage. Collectively, our study for the first time demonstrates that sperm-borne small RNA plays a crucial role in the developmental competence of SCNT embryos by regulating H3K9me3 and Ac α-tubulin K40. Further studies will be required to determine how sperm small RNA regulate the H3K9me3 and Acα-tubulin K40. Our study suggests that the supplementation of sperm-borne small RNA is a potential application to improve the cloning efficiency.


Assuntos
Técnicas de Transferência Nuclear , Espermatozoides/metabolismo , Tubulina (Proteína)/metabolismo , Acetilação , Animais , Apoptose/fisiologia , Blastocisto/citologia , Blastocisto/metabolismo , Bovinos , Epigênese Genética/genética , Imunofluorescência , Histonas/metabolismo , Masculino , Microscopia Confocal , Reação em Cadeia da Polimerase , Processamento de Proteína Pós-Traducional , Tubulina (Proteína)/genética
16.
Small ; 14(48): e1803233, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30334350

RESUMO

Durability is still one of the key obstacles for the further development of photocatalytic energy-conversion systems, especially low-dimensional ones. Encouragingly, recent studies show that nanoinsulators such as SiO2 and MgO exhibit substantially enhanced photocatalytic durability than the typical semiconductor p25 TiO2 . Extending this knowledge, MgO-Au plasmonic defect nanosystems are developed that combine the stable photoactivity from MgO surface defects with energy-focusing plasmonics from Au nanoparticles (NPs), where Au NPs are anchored onto monodispersed MgO nanotemplates. Theoretical calculations reveal that the midgap defect (MGD) states in MgO are generated by oxygen vacancies, which provide the main avenues for upward electron transitions under photoexcitation. These electrons drive stable proton photoreduction to H2 gas via water splitting. A synergistic interaction between Au's localized plasmons and MgO's oxygen vacancies is observed here, which enhances MgO's photoactivity and stability simultaneously. Such co-enhancement is attributed to the stable longitudinal-plasmon-free Au NPs, which provide robust hot electrons capable of overcoming the interband transition barrier (≈1.8 eV) to reach proton reduction potential for H2 generation. The demonstrated plasmonic defect nanosystems are expected to open a new avenue for developing highly endurable photoredox systems for the integration of multifunctionalities in energy conversion, environmental decontamination, and climate change mitigation.

17.
Tumour Biol ; 37(8): 11007-15, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26894601

RESUMO

The PI3K/Akt/mTOR axis in ovarian cancer is frequently activated and implicated in tumorigenesis. Specific targeting of this pathway is therefore an attractive therapeutic approach for ovarian cancer. However, ovarian cancer cells are resistant to PP242, a dual inhibitor of mTORC1 and mTORC2. Interestingly, blockage of GLS1 with a selective inhibitor, CB839, or siRNA dramatically sensitized the PP242-induced cell death, as evident from increased PARP cleavage. The anti-cancer activity of CB-839 and PP242 was abrogated by the addition of the TCA cycle product α-ketoglutarate, indicating the critical function of GLS1 in ovarian cancer cell survival. Finally, glutaminolysis inhibition activated apoptosis and synergistically sensitized ovarian cancer cells to priming with the mTOR inhibitor PP242. GLS1 inhibition significantly reduced phosphorylated STAT3 expression in ovarian cancer cells. These findings show that targeting glutamine addiction via GLS1 inhibition offers a potential novel therapeutic strategy to overcome resistance to PI3K/Akt/mTOR inhibition.


Assuntos
Resistencia a Medicamentos Antineoplásicos/fisiologia , Glutaminase/metabolismo , Neoplasias Ovarianas/metabolismo , Fator de Transcrição STAT3/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzenoacetamidas/farmacologia , Western Blotting , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Glutamina/metabolismo , Humanos , Indóis/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Tiadiazóis/farmacologia
18.
Inorg Chem ; 55(6): 2765-70, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26962880

RESUMO

High-quality α-MnSe nanocubes were successfully prepared for the first time by an effective hot injection synthesis strategy. This approach was simple but robust and had been applied to the controllable synthesis of different sizes and diverse morphologies of α-MnSe nanostructures. The crystal phases, compositions, and microstructures of these nanostructures had been systematically characterized with a series of techniques. As a proof-of-concept application, the as-prepared α-MnSe nanocubes were used as an anode material for a lithium ion battery, which exhibited superior rate ability and ultralong cycle stability in half-cell and full-cell tests. Importantly, the phase transition from α-MnSe to ß-MnSe during the electrochemical process was proved by ex situ X-ray diffraction and selected area electron diffraction. The excellent electrochemical performance of α-MnSe endowed its potential as an anode material candidate for high performance lithium storage.

19.
Chemistry ; 21(34): 11954-60, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26100433

RESUMO

Various lanthanide oxides (Sm2 O3 and Gd2 O3 ) nanostructures were synthesized by a facile hydrothermal method. The loss of surfactants on the nanocrystals surface, followed by the resultant assembly is responsible for the formation of ultrathin nanosheets. Owing to strong surface effects, the different morphologies of the Sm2 O3 :5 % Eu and Gd2 O3 :5 % Eu nanocrystals present unique photoluminescence properties. As a proof-of-concept application, the as-obtained Sm2 O3 and Gd2 O3 ultrathin nanosheets exhibit promising pH-controlled anticancer drug-delivery behavior.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Gadolínio/química , Elementos da Série dos Lantanídeos/química , Nanopartículas/química , Nanoestruturas/química , Óxidos/síntese química , Antineoplásicos/química , Sistemas de Liberação de Medicamentos , Gadolínio/metabolismo , Concentração de Íons de Hidrogênio , Luminescência , Óxidos/química , Tamanho da Partícula , Samário/química , Propriedades de Superfície
20.
Small ; 10(22): 4727-34, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25302745

RESUMO

Tetrapod-shaped CdS colloidal nanocrystals are synthesized using a facile, phosphine-free synthesis approach at low temperature. The arm length and diameter of CdS tetrapods can be easily tuned by using different source of sulphureous precursors, i.e., sulfur powder, thioacetamide, and sodium diethyldithiocarbamate. Moreover, the growth of Au nanoparticles onto CdS to form metal-semiconductor hybrid nanocrystals is also demonstrated. The tetrapod-shaped CdS nanocrystals exhibit strong arm-diameter-dependent absorption and photoluminescence characteristics. Importantly, the as-obtained CdS tetrapods exhibit promising photocatalytic activity for the water-splitting reaction in photoelectrochemical cells.


Assuntos
Compostos de Cádmio/química , Temperatura Baixa , Ouro/química , Nanopartículas Metálicas/química , Fosfinas/química , Sulfetos/química , Coloides , Microscopia Eletrônica de Transmissão
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