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1.
J Am Chem Soc ; 146(12): 8260-8268, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38497725

ABSTRACT

We report the synthesis, crystal structure, and physical properties of a novel ternary compound, Th2Cu4As5. The material crystallizes in a tetragonal structure with lattice parameters a = 4.0639(3) Å and c = 24.8221(17) Å. Its structure can be described as an alternating stacking of fluorite-type Th2As2 layers with antifluorite-type double-layered Cu4As3 slabs. The measurement of electrical resistivity, magnetic susceptibility, and specific heat reveals that Th2Cu4As5 undergoes bulk superconducting transition at 4.2 K. Additionally, all these physical quantities exhibit anomalies at 48 K, accompanied by a sign change in the Hall coefficient, suggesting a charge-density-wave-like (CDW) phase transition. Drawing from both experimental data and band calculations, we propose that the superconducting and CDW-like phase transitions are, respectively, associated with the Cu4As3 slabs and the As plane in the Th2As2 layers.

2.
Small ; : e2401812, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816772

ABSTRACT

Carbon quantum dots (C-dots) have emerged as efficient fluorescent materials for solid-state lighting devices. However, it is still a challenge to obtain highly bright solid-state C-dots because of the aggregation caused quenching. Compared to the encapsulation of as-prepared C-dots in matrices, one-step preparation of C-dots/matrix complex is a good method to obtain highly bright solid-state C-dots, which is still quite limited. Here, an efficient and controllable vacuum-boosting gradient heating approach is demonstrated for in situ synthesis of a stable and efficient C-dots/matrix complex. The addition of boric acid strongly bonded with urea, promoting the selectivity of the reaction between citric acid and urea. Benefiting from the high reaction selectivity and spatial-confinement growth of C-dots in porous matrices, in situ synthesize C-dots bonded can synthesized dominantly with a crosslinked octa-cyclic compound, biuret and cyanuric acid (triuret). The obtained C-dots/matrix complex exhibited bright green emission with a quantum yield as high as 90% and excellent thermal and photo stability. As a proof-of-concept, the as-prepared C-dots are used for the fabrication of white light-emitting diodes (LEDs) with a color rendering index of 84 and luminous efficiency of 88.14 lm W-1, showing great potential for applications in LEDs.

3.
Small ; 20(11): e2306690, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37926792

ABSTRACT

Non-aqueous solvents, in particular N,N-dimethylaniline (NMP), are widely applied for electrode fabrication since most sodium layered oxide cathode materials are readily damaged by water molecules. However, the expensive price and poisonousness of NMP unquestionably increase the cost of preparation and post-processing. Therefore, developing an intrinsically stable cathode material that can implement the water-soluble binder to fabricate an electrode is urgent. Herein, a stable nanosheet-like Mn-based cathode material is synthesized as a prototype to verify its practical applicability in sodium-ion batteries (SIBs). The as-prepared material displays excellent electrochemical performance and remarkable water stability, and it still maintains a satisfactory performance of 79.6% capacity retention after 500 cycles even after water treatment. The in situ X-ray diffraction (XRD) demonstrates that the synthesized material shows an absolute solid-solution reaction mechanism and near-zero-strain. Moreover, the electrochemical performance of the electrode fabricated with a water-soluble binder shows excellent long-cycling stability (67.9% capacity retention after 500 cycles). This work may offer new insights into the rational design of marvelous water stability cathode materials for practical SIBs.

4.
Insect Mol Biol ; 2024 May 06.
Article in English | MEDLINE | ID: mdl-38709468

ABSTRACT

Cordyceps cicadae (Hypocreales: Cordycipitaceae) is a renowned entomopathogenic fungus used as herbal medicine in China. However, wild C. cicadae resources have been threatened by heavy harvesting. We hypothesised that Bombyx mori L. (Lepidoptera: Bombycidae) could be a new alternative to cultivate C. cicadae due to the low cost of rearing. Bacterial communities are crucial for the formation of Cordyceps and for promoting the production of metabolites. To better understand the bacterial community structure associated with Cordyceps, three Claviciptaceae fungi were used to explore the pathogenicity of the silkworms. Here, fifth-instar silkworms were infected with C. cicadae, Cordyceps cateniannulata (Hypocreales: Cordycipitaceae) and Beauveria bassiana (Hypocreales: Cordycipitaceae). Subsequently, we applied high-throughput sequencing to explore the composition of bacterial communities in silkworms. Our results showed that all three fungi were highly pathogenic to silkworms, which suggests that silkworms have the potential to cultivate Cordyceps. After fungal infection, the diversity of bacterial communities in silkworms decreased significantly, and the abundance of Staphylococcus increased in mummified larvae, which may play a role in the death process when the host suffers infection by entomopathogenic fungi. Furthermore, there were high similarities in the bacterial community composition and function in the C. cicadae and C. cateniannulata infected samples, and the phylogenetic analysis suggested that these similarities may be related to the fungal phylogenetic relationship. Our findings reveal that infection with different entomopathogenic fungi affects the composition and function of bacterial communities in silkworms and that the bacterial species associated with Cordyceps are primarily host dependent, while fungal infection affects bacterial abundance.

5.
Inorg Chem ; 63(1): 211-218, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38153326

ABSTRACT

A quaternary compound, ThCr2Si2C, was synthesized by using the arc-melting technique. The compound adopts a tetragonal CeCr2Si2C-type crystal structure. The electronic resistivity and specific heat data exhibit metallic behavior, while the magnetic susceptibility displays a pronounced broad peak at around 370 K, indicating the antiferromagnetic phase transition. The first-principles calculations suggest A-type antiferromagnetic ordering of the Cr sublattice, which is confirmed by neutron diffraction experiments. By comparing the crystal structure of ThCr2Si2C with the isostructural Cr-based compounds, the magnetic state of Cr 3d orbital is discussed in terms of the band-filling effects and indirect spin exchange interaction.

6.
Nano Lett ; 22(7): 2907-2914, 2022 Apr 13.
Article in English | MEDLINE | ID: mdl-35362973

ABSTRACT

The quantum-confinement effect profoundly influences the exciton energy-level structures and recombination dynamics of semiconductor nanostructures but remains largely unexplored in traditional one-dimensional nanowires mainly due to their poor optical qualities. Here, we show that in defect-tolerant perovskite material of highly luminescent CsPbBr3 nanowires, the exciton's center-of-mass motion perpendicular to the axial direction is severely confined. This is reflected in the two sets of photoluminescence spectra emitted from a single CsPbBr3 nanowire, each of which consists of doublet peaks with linear polarizations perpendicular and parallel to the axial direction. Moreover, different exciton states can be mixed by the Rashba spin-orbit coupling effect, resulting in two single photoluminescence peaks with linear polarizations both along the nanowire axis. The above findings mark the emergence of an ideal platform for the exploration of intrinsic one-dimensional exciton photophysics and optoelectronics, thus bridging the long-missing research gap between the well-studied two- and zero-dimensional semiconductor nanostructures.

7.
Phys Rev Lett ; 128(10): 106802, 2022 Mar 11.
Article in English | MEDLINE | ID: mdl-35333064

ABSTRACT

By combining angle-resolved photoemission spectroscopy, scanning tunneling microscopy, atomic force microscope based piezoresponse force microscopy and first-principles calculations, we have studied the low-energy band structure, atomic structure, and charge polarization on the surface of a topological semimetal candidate TaNiTe_{5}. Dirac-like surface states were observed on the (010) surface by angle-resolved photoemission spectroscopy, consistent with the first-principles calculations. On the other hand, piezoresponse force microscopy reveals a switchable ferroelectriclike polarization on the same surface. We propose that the noncentrosymmetric surface relaxation observed by scanning tunneling microscopy could be the origin of the observed ferroelectriclike state in this novel material. Our findings provide a new platform with the coexistence of a ferroelectriclike surface charge distribution and novel surface states.

8.
Neoplasma ; 69(6): 1349-1358, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36305691

ABSTRACT

Previous studies have shown that PHF21A is associated with the initiation and progression of various tumors. However, its role in hepatocellular carcinoma (HCC) is still unclear. Thus, this study aimed to determine the expression and clinical significance of PHF21A in HCC. PHF21A expression in 201 liver cancer samples and 129 adjacent normal tissues was detected by immunohistochemistry. The correlation between PHF21A expression and the clinicopathological features and prognosis of HCC was verified in 70 other liver tissue microarray samples. The relationship between PHF21A expression and HCC immune cell infiltration was explored via the Tumor Immune Estimation Resource (TIMER). The mechanism underlying the effect of PHF21A on HCC progression was analyzed by gene set enrichment analysis (GSEA) and protein-protein interaction (PPI) network analysis. Immunohistochemical staining showed that PHF21A expression in HCC tissue was significantly lower than that in adjacent nontumor liver tissue and was associated with patient sex, tumor size, metastasis, and Edmondson grade (p<0.05). Kaplan-Meier analysis demonstrated that low PHF21A expression was associated with a poor prognosis, and Cox regression analysis showed that PHF21A was an independent predictor of prognosis. TIMER analysis showed that PHF21A is positively correlated with tumor immune cell infiltration levels. Functional annotation indicated that PHF21A is involved in important pathways, including transcriptional deregulation pathways in cancer. Finally, in vitro experiments confirmed the low expression of PHF21A in HCC cells. PHF21A affects the progression and prognosis of HCC, suggesting that PHF21A may play an important role in monitoring and preventing the development of HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , Prognosis , Biomarkers , Kaplan-Meier Estimate , Biomarkers, Tumor/metabolism , Histone Deacetylases
9.
Small ; 17(10): e2008133, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33586294

ABSTRACT

Conversion-alloy sulfide materials for potassium-ion batteries (KIBs) have attracted considerable attention because of their high capacities and suitable working potentials. However, the sluggish kinetics and sulfur loss result in their rapid capacity degeneration as well as inferior rate capability. Herein, a strategy that uses the confinement and catalyzed effect of Nb2 O5 layers to restrict the sulfur species and facilitate them to form sulfides reversibly is proposed. Taking Sb2 S3 anode as an example, Sb2 S3 and Nb2 O5 are dispersed in the core and shell layers of carbon nanofibers (C NFs), respectively, constructing core@shell structure Sb2 S3 -C@Nb2 O5 -C NFs. Benefiting from the bi-functional Nb2 O5 layers, the electrochemical reversibility of Sb2 S3 is stimulated. As a result, the Sb2 S3 -C@Nb2 O5 -C NFs electrode delivers the rapidest K-ion diffusion coefficient, longest cycling stability, and most excellent rate capability among the controlled electrodes (347.5 mAh g-1 is kept at 0.1 A g-1 after 100 cycles, and a negligible capacity degradation (0.03% per cycle) at 2.0 A g-1 for 2200 cycles is delivered). The enhanced K-ion storage properties are also found in SnS2 -C@Nb2 O5 -C NFs electrode. Encouraged by the stimulated reversibility of Sb2 S3 and SnS2 anodes, other sulfides with high electrochemical performance also could be developed for KIBs.

10.
J Transl Med ; 19(1): 280, 2021 06 30.
Article in English | MEDLINE | ID: mdl-34193174

ABSTRACT

BACKGROUND: Colorectal cancer is the third most common diagnosis. Oxaliplatin is used as first-line treatment of colon cancer. However, oxaliplatin resistance greatly reduces its therapeutic effect. SRPK1 involves in pre-mRNA splicing and tumorigenesis. How SRPK1 mediates drug resistance in colon cancer is unknown. METHODS: The expression of SRPK1 was analyzed in the TCGA and the CPTAC pan-cancer samples and detected in colon cancer cell lines and tissues by IHC and western blot. The MTT and TUNEL assay were used to verify the anti-apoptosis ability of colon cancer cell. The activation of NF-κB was determined by luciferase assay and qRT-PCR. AKT, IKK, IκB and their phosphorylation level were verified by western blot. RESULTS: We found that SRPK1 expression was the second highest in TCGA and the CPTAC pan-cancer samples. The mRNA and protein levels of SRPK1 were increased in tissues from patients with colon cancer. SRPK1 was associated with clinical stage and TNM classifications in 148 cases of colon cancer patients. High SRPK1 levels correlated with poor prognosis (p < 0.001). SRPK1 overexpression enhanced the anti-apoptosis ability of colon cancer cells, whereas SRPK1 silencing had the opposite effect under oxaliplatin treatment. Mechanistically, SRPK1 enhances IKK kinase and IκB phosphorylation to promote NF-κB nuclear translocation to confer oxaliplatin resistance. CONCLUSIONS: Our findings suggest that SRPK1 participates in colon cancer progression and enhances the anti-apoptosis capacity to induce drug resistance in colon cancer cells via NF-κB pathway activation, and thus might be a potential pharmaceutically target for colon cancer treatment.


Subject(s)
Colonic Neoplasms , NF-kappa B , Apoptosis , Cell Line, Tumor , Colonic Neoplasms/drug therapy , Colonic Neoplasms/genetics , Humans , Oxaliplatin/pharmacology , Oxaliplatin/therapeutic use , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins c-akt
11.
BMC Endocr Disord ; 21(1): 208, 2021 Oct 21.
Article in English | MEDLINE | ID: mdl-34670546

ABSTRACT

BACKGROUND: To assess the gaps between the initial management of patients with differentiated thyroid cancer (DTC) in real clinical practice and the recommendations of the 2012 Chinese DTC guidelines. METHODS: This multicenter, prospective study was conducted at nine tertiary hospitals across China. Eligible patients were those having intermediate or high-risk DTC after first-time thyroidectomy. During 1 year of follow-up, comprehensive medical records were collected and summarized using descriptive statistics. RESULTS: Of 2013 patients, 1874 (93.1%) underwent standard surgery according to the guidelines (including total lobectomy plus isthmusectomy and total/near total thyroidectomy), and 1993 (99.0%) underwent lymph node dissection; only 56 (2.8%) had postoperative complications. Overall, 982/2013 patients (48.8%) received radioactive iodine (RAI) therapy after thyroidectomy. Of all enrolled patients, 61.4% achieved the target serum thyroid-stimulating hormone level, with a median time to target of 234.0 days (95% CI: 222.0-252.0). At 1 year of follow-up, proportions of patients with excellent response, incomplete structural response, biochemical incomplete response, and indeterminate response were 34.6, 11.2, 6.6, and 47.5%, respectively; recurrence or metastasis occurred in 27 patients (1.3%). During the overall study period, 209 patients (10.4%) had at least one adverse event: 65.1% of cases were mild, 24.9% moderate, and 10.1% severe. CONCLUSIONS: This was the first large-scale prospective study of how patients with DTC in China are treated in actual practice. Initial DTC management is generally safe and adheres to the 2012 Chinese guidelines but could be improved, and the level of guideline adherence did not produce the anticipated treatment response at 1 year of follow-up.


Subject(s)
Iodine Radioisotopes/therapeutic use , Thyroid Cancer, Papillary/therapy , Thyroid Neoplasms/therapy , Thyroidectomy/statistics & numerical data , Thyrotropin/antagonists & inhibitors , Adult , China , Combined Modality Therapy , Female , Guideline Adherence , Humans , Lymph Node Excision/statistics & numerical data , Male , Middle Aged , Prospective Studies , Thyroxine/therapeutic use
12.
Inorg Chem ; 59(5): 2937-2944, 2020 Mar 02.
Article in English | MEDLINE | ID: mdl-32064866

ABSTRACT

Mn-based ZrCuSiAs-type pnictides ThMnPnN (Pn = P, As) containing PbO-type Th2N2 layers were synthesized. The crystal and magnetic structures are determined using X-ray and neutron powder diffraction. While neutron diffraction indicates a C-type antiferromagnetic state at 300 K, the temperature dependence of the magnetic susceptibility shows cusps at 36 and 52 K respectively for ThMnPN and ThMnAsN. The susceptibility cusps are ascribed to a spontaneous antiferromagnetic-to-antiferromagnetic transition for Mn2+ moments, which is observed for the first time in Mn-based ZrCuSiAs-type compounds. In addition, measurements of the resistivity and specific heat suggest an abnormal increase in the density of states at the Fermi energy. The result is discussed in terms of the internal chemical pressure effect.

13.
Med Sci Monit ; 26: e919302, 2020 Jan 22.
Article in English | MEDLINE | ID: mdl-31967986

ABSTRACT

BACKGROUND Thyroid cancer (TC) is one of the most prevalent endocrine malignancies and there may be many unclarified molecular events and gene types involved in TC. The objective of this study was to assess the clinical implications and potential mechanisms of serum response factor (SRF) in TC. MATERIAL AND METHODS RNA-sequencing and gene chip data with TC expression were collected from The Cancer Genome Atlas/Genotype-Tissue Expression, Gene Expression Omnibus, ArrayExpress, Sequence Read Archive, and Oncomine. SRF expression of all TC and adjacent non-cancerous tissue were calculated using the t test, STATA, and Meta-DiSc. The related pathways of the potential SRF target genes and target miRNAs were explored. Dual-luciferase reporter assay was performed to validate the association between SRF and its putative miRNA. RESULTS One RNA-sequencing and 15 gene chips were collected, and the pooled standardized mean difference of SRF was -1.00. Furthermore, the area under the curve of sROC of SRF in TC was 0.8251, indicating a dramatic decreased expression of SRF in TC tissues based on 1118 cases. The intersection of differentially expressed genes in TC, SRF co-expressed genes, and SRF potential target genes achieved from Cistrome Cancer led to 169 overlapped genes. miR-330-5p was predicted to target SRF, which was further confirmed by dual-luciferase reporter assay. CONCLUSIONS The reduction of SRF appears to play a crucial role in the origin of TC. These properties are accomplished by the target genes of SRF, as a transcription factor, or by the axes with the associated miRNAs.


Subject(s)
Serum Response Factor/analysis , Thyroid Neoplasms/genetics , Thyroid Neoplasms/metabolism , Databases, Genetic , Gene Expression Profiling/methods , Gene Expression Regulation/genetics , Humans , MicroRNAs/genetics , Oligonucleotide Array Sequence Analysis/methods , Sequence Analysis, RNA/methods , Serum Response Factor/blood , Thyroid Neoplasms/physiopathology , Exome Sequencing/methods
14.
J Med Internet Res ; 22(10): e21301, 2020 10 05.
Article in English | MEDLINE | ID: mdl-32997639

ABSTRACT

BACKGROUND: The COVID-19 outbreak has affected people's health worldwide. For college students, web-based physical education is a challenge, as these course are normally offered outdoors. OBJECTIVE: The aim of this study was to use data from a web-based survey to evaluate the relationship between the mental health status of college students and their sports-related lifestyles. Problems related to web-based physical education were also examined. METHODS: A web-based survey was conducted by snowball sampling from May 8 to 11, 2020. Demographic data, mental health status, and sports-related lifestyles of college students in Wuhan as well as issues related to web-based physical education were collected. Mental health status was assessed by the Depression, Anxiety, and Stress Scale (DASS-21). RESULTS: The study included 1607 respondents from 267 cities. The average scores of the DASS-21 subscales (2.46 for depression, 1.48 for anxiety, and 2.59 for stress) were significantly lower in our study than in a previous study (P<.05). Lower DASS-21 scores were significantly correlated with regular exercise, maintaining exercise habits during the outbreak of COVID-19, exercising more than 1 to 2 times a week, exercise duration >1 hour, and >2000 pedometer steps (all P<.05). None of the three forms of web-based physical education was preferred by more than 50% of respondents. Frequent technical problems were confronted by 1087/1607 students (67.6%). Shape-up exercises (846/1607, 52.6%), a designed combination of exercises (710/1607, 44.2%), and Chinese kung fu (559/1607, 34.8%) were suggested sports for web-based physical education. CONCLUSIONS: Mental status was significantly correlated with regular exercise and sufficient exercise duration. Professional physical guidance is needed for college students in selected sports. Exercises not meeting students' preferences, frequent technical problems, and the distant interaction involved in web-based physical education were the main problems that should be solved in future.


Subject(s)
Coronavirus Infections/epidemiology , Exercise/psychology , Mental Health , Physical Education and Training/trends , Pneumonia, Viral/epidemiology , Social Isolation/psychology , Students/psychology , Adolescent , Anxiety/epidemiology , Anxiety Disorders/epidemiology , Betacoronavirus , COVID-19 , China , Cross-Sectional Studies , Education, Distance/methods , Female , Humans , Internet , Life Style , Male , Pandemics , SARS-CoV-2 , Sports , Surveys and Questionnaires , Young Adult
15.
J Transl Med ; 17(1): 143, 2019 05 06.
Article in English | MEDLINE | ID: mdl-31060551

ABSTRACT

BACKGROUND: The distant metastasis of cancer cells is a risk factor for tumor lethality and poor prognosis in non-small-cell lung carcinoma (NSCLC). Increased SOX9 expression has been associated with clinical stage and poor prognosis in NSCLC, but the molecular mechanisms by which SOX9 promotes metastasis in NSCLC are still unknown. METHODS: The relationship between SOX9 expression and T, N, M classification was assessed using the χ2 test and Spearman's analysis in 142 immunohistochemically diagnosed specimens of NSCLC. We also generated SOX9-overexpression and SOX9-knockdown cells lines and their corresponding control cell lines by transfection with lentiviral constructs. In vivo assay, SOX9-overexpressing and SOX9-knockdown NSCLC cells were injected in zebrafish to examine distance metastasis. Gene set enrichment analysis (GSEA) was applied to analysis the correlation between SOX9 overexpression and Wnt/ß-catenin pathway. Luciferase assay was used to check transcriptional activity of TCF/LEF and western blot and immunofluorescence was employed to detect ß-catenin translocation in SOX9-overexpression, SOX9-knockdown and their corresponding control cell lines. RESULTS: We found that SOX9 overexpression correlates with the T, N and M stage significantly (p = 0.03, 0.000, and 0.032 respectively) in 142 immunohistochemically diagnosed specimens of NSCLC. SOX9 overexpression was found to decrease the expression of the epithelial cell markers E-cadherin and γ-catenin and increase the expression of the mesenchymal cell markers N-cadherin and vimentin. An in vivo assay showed distant metastasis of the SOX9-overexpressing cells, which was not observed in the SOX9-knockdown cells. These findings indicate that SOX9 promotes distant metastasis by promoting EMT in NSCLC cells. GSEA showed that SOX9 overexpression was significantly correlated with the Wnt/ß-catenin pathway which was corroborated by the expression of EMT-associated proteins in this pathway and its downstream target genes. SOX9 overexpression was also found to enhance the transcriptional activity of TCF/LEF, promote the nuclear translocation of ß-catenin and increase the phosphorylation of GSK3ß at Ser9. Further, inhibition of ß-catenin suppressed the metastasis-promoting effects of SOX9 overexpression. CONCLUSIONS: This study is the first to report that SOX9 is associated with clinical TNM stage and indicates that SOX9 promotes migration, invasion and the EMT process through the Wnt/ß-catenin pathway.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Epithelial-Mesenchymal Transition , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , SOX9 Transcription Factor/metabolism , Wnt Signaling Pathway , Animals , Cell Line, Tumor , Cell Movement/drug effects , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Epithelial-Mesenchymal Transition/drug effects , Heterocyclic Compounds, 3-Ring/pharmacology , Humans , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasm Staging , Wnt Signaling Pathway/drug effects , Zebrafish , beta Catenin/metabolism
16.
Langmuir ; 35(19): 6321-6332, 2019 May 14.
Article in English | MEDLINE | ID: mdl-31009568

ABSTRACT

A new strategy has been innovatively proposed for wrapping the Ni-incorporated and N-doped carbon nanotube arrays (Ni-NCNTs) on porous Si with robust Ni-Si interfacial bonding to form the core-shell-structured NCNTs-Ni2Si@Si. The hierarchical porous silicon core was first fabricated via a novel self-templating synthesis route based on two crucial strategies: in situ thermal evaporation of crystal water from the perlite for producing porous SiO2 and subsequent magnesiothermic reduction of porous SiO2 into porous Si. Ni-NCNTs were subsequently constructed based on the Ni-catalyzed tip-growth mechanism and were further engineered to fully wrap the porous Si microparticles by forming the Ni2Si alloy at the heterojunction interface. When the prepared NCNTs-Ni2Si@Si was evaluated as the anode material for Li-ion batteries, the hierarchical porous system in the Si core and the rich void spaces in carbon nanotube arrays contributed to the remarkable accommodation of volume expansion of Si as well as the significant increase of Li+ diffusion and Si utilization. Moreover, the Ni2Si alloy, which chemically linked the Ni-NCNTs and porous Si, not only provided good electronic contact between the Si core and carbon shell but also effectively prevented the CNTs' detachment from the Si core during cycling. The multifunctional structural design rendered the whole electrode highly stable and active in Li storage, and the electrochemically active NCNTs-Ni2Si@Si electrode delivered a high reversible capacity of 1547 mAh g-1 and excellent cycling stability (85% capacity retention after 600 discharge-charge cycles) at a current density of 358 mA g-1 (0.1 C) as well as good rate performance (778 mAh g-1 at 2 C), showing great potential as an efficient and stable anode for high energy density Li-ion batteries.

17.
BMC Genomics ; 19(1): 349, 2018 May 10.
Article in English | MEDLINE | ID: mdl-29747586

ABSTRACT

BACKGROUND: Cell-type-specific genes exhibit heterogeneity in genomic contexts and may be subject to different epigenetic regulations through different gene transcriptional processes depending on the cell type involved. The gene-body regions (GBRs) of some cardiomyocyte (CM)-specific genes are long and highly hypomethylated in CMs. To explore the cell-type specificities of epigenetic patterns and functions, multiple epigenetic modifications of GBRs were compared among CMs, liver cells and embryonic stem cells (ESCs). RESULTS: We found that most genes show a moderately negative correlation between transcript levels and gene lengths. As CM-specific genes are generally longer than other cell-type-specific genes, we hypothesized that the gene-body epigenetic features of CMs may support the transcriptional regulation of CM-specific genes. We found gene-body DNA hypomethylation in a CM-specific gene subset co-localized with rare gene-body marks, including RNA polymerase II (Pol II) and p300. Interestingly, 5-hydroxymethylcytosine (5hmC) within the gene body marked cell-type-specific genes at neonatal stages and active gene-body histone mark H3K36 trimethylation declined and overlapped with cell-type-specific gene-body DNA hypomethylation and selective Pol II/p300 accumulation in adulthood. Different combinations of gene-body epigenetic modifications were also observed with genome-wide scale cell-type specificity, revealing the occurrence of dynamic epigenetic rearrangements in GBRs across different cell types. CONCLUSIONS: As 5hmC enrichment proceeded to hypomethylated GBRs, we considered that hypomethylation may not represent a static state but rather an equilibrium state of turnover due to the balance between local methylation linked to transcription and Tet oxidative modification causing demethylation. Accordingly, we conclude that demethylation in CMs can be a used to establish such cell-type-specific epigenetic domains in relation to liver cells. The establishment of cell-type-specific epigenetic control may also change genomic contexts of evolution and may contribute to the development of cell-type-specific transcriptional coordination.


Subject(s)
DNA Methylation , Demethylation , Epigenesis, Genetic , Genetic Linkage , Myocytes, Cardiac/metabolism , Transcription, Genetic , 5-Methylcytosine/analogs & derivatives , 5-Methylcytosine/metabolism , Animals , Cell Lineage/genetics , Embryonic Stem Cells , Female , Genes, Essential , Liver/metabolism , Male , Mice, Inbred C57BL
19.
J Surg Res ; 214: 162-167, 2017 06 15.
Article in English | MEDLINE | ID: mdl-28624039

ABSTRACT

BACKGROUND: Central lymph node (CLN) metastasis in papillary thyroid carcinoma (PTC) is common and being able to predict CLN metastasis helps surgeons determine individualized therapy. However, the relationship between contralateral CLN metastasis and the total number of positive lymph nodes (LNs) in the combined prelaryngeal and pretracheal region remains unclear. This study aimed to investigate whether the total number of positive LNs in the combined prelaryngeal and pretracheal region has clinical significance as a predictor for contralateral CLN metastasis. METHODS: We prospectively enrolled 153 consecutive patients with unifocal PTC >1.0 cm without ultrasonographic evidence of nodal metastasis who underwent total thyroidectomy and prophylactic bilateral CLN dissection from July 2011-May 2013. Patients were divided into three groups according to the total number of positive LNs in the combined prelaryngeal and pretracheal region. RESULTS: Rates of metastasis to ipsilateral and contralateral central compartments in PTC >1.0 cm were 84.3% and 24.2%, respectively. Multivariate analysis showed that ≥3 positive LNs in the combined prelaryngeal and pretracheal region were an independent predictive factor of contralateral CLN metastasis (P < 0.001; odds ratio, 8.585). After a mean follow-up of 24.1 mo, none of these patients had a recurrence in the central or lateral compartment. CONCLUSIONS: Occult metastasis is highly prevalent in the ipsilateral central neck of patients with PTC >1.0 cm, and the total number of prelaryngeal and pretracheal LNs metastases may be a useful indicator to predict contralateral CLN metastasis in patients with unifocal PTC.


Subject(s)
Carcinoma/pathology , Lymph Nodes/pathology , Thyroid Neoplasms/pathology , Adolescent , Adult , Aged , Carcinoma/surgery , Carcinoma, Papillary , Child , Female , Follow-Up Studies , Humans , Larynx , Logistic Models , Lymph Node Excision , Lymph Nodes/surgery , Lymphatic Metastasis , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Risk Factors , Thyroid Cancer, Papillary , Thyroid Neoplasms/surgery , Thyroidectomy , Trachea , Young Adult
20.
Inorg Chem ; 56(21): 12775-12782, 2017 Nov 06.
Article in English | MEDLINE | ID: mdl-29027802

ABSTRACT

The metal-to-core charge transfer (MCCT) transition in sensitized titanium-oxo clusters is an important process for photoinduced electron injection in photovoltaic conversion. This process resembles most closely the Type II photoinjection in dye-sensitized solar cells. Herein we report the synthesis and photophysical and photoelectrochemical (PEC) properties of the phosphonate-stabilized titanium-oxo clusters containing the ferrocenecarboxylate ligands. These ferrocene-containing clusters exhibit intense visible absorption extended up to 600 nm along with low optical band gaps of ∼2.2 eV. The low-energy transitions of these clusters were systematically investigated by UV-vis spectroscopy and DFT/TDDFT calculations. The combined experimental and computational studies suggest that the ferrocenecarboxylate-substituted titanium-oxo clusters form a donor-acceptor (D-A) system. The low-energy transition of these clusters primarily involves the MCCT from the iron center to TiO cluster core. The TiO core structure and phosphonate ligands both have great influence on the PEC properties of the clusters. This work provides valuable examples for the sensitized titanium-oxo clusters in which electron injection takes place via MCCT transition.

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