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1.
Nano Lett ; 24(2): 741-747, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38166145

RESUMO

The emergence of one-dimensional van der Waals heterostructures (1D vdWHs) opens up potential fields with unique properties, but precise synthesis remains a challenge. The utilization of mixed conductive types of carbon nanotubes as templates has imposed restrictions on the investigation of the electrical behavior and interlayer interaction of 1D vdWHs. In this study, we efficiently encapsulated silver iodide in high-purity semiconducting single-walled carbon nanotubes (sSWCNTs), forming 1D AgI@sSWCNT vdWHs. We characterized the semiconductor-metal transition and increased the carrier concentration of individual AgI@sSWCNTs via sensitive dielectric force microscopy and confirmed the results through electrical device tests. The electrical behavior transition was attributed to an interlayer charge transfer, as demonstrated by Kelvin probe force microscopy. Furthermore, we showed that this method of synthesizing 1D heterostructures can be extended to other metal halides. This work opens the door for the further exploration of the electrical properties of 1D vdWHs.

2.
Med Res Rev ; 44(3): 1013-1054, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38140851

RESUMO

The burgeoning prodrug strategy offers a promising avenue toward improving the efficacy and specificity of cytotoxic drugs. Elevated intracellular levels of glutathione (GSH) have been regarded as a hallmark of tumor cells and characteristic feature of the tumor microenvironment. Considering the pivotal involvement of elevated GSH in the tumorigenic process, a diverse repertoire of GSH-triggered prodrugs has been developed for cancer therapy, facilitating the attenuation of deleterious side effects associated with conventional chemotherapeutic agents and/or the attainment of more efficacious therapeutic outcomes. These prodrug formulations encompass a spectrum of architectures, spanning from small molecules to polymer-based and organic-inorganic nanomaterial constructs. Although the GSH-triggered prodrugs have been gaining increasing interests, a comprehensive review of the advancements made in the field is still lacking. To fill the existing lacuna, this review undertakes a retrospective analysis of noteworthy research endeavors, based on a categorization of these molecules by their diverse recognition units (i.e., disulfides, diselenides, Michael acceptors, and sulfonamides/sulfonates). This review also focuses on explaining the distinct benefits of employing various chemical architecture strategies in the design of these prodrug agents. Furthermore, we highlight the potential for synergistic functionality by incorporating multiple-targeting conjugates, theranostic entities, and combinational treatment modalities, all of which rely on the GSH-triggering. Overall, an extensive overview of the emerging field is presented in this review, highlighting the obstacles and opportunities that lie ahead. Our overarching goal is to furnish methodological guidance for the development of more efficacious GSH-triggered prodrugs in the future. By assessing the pros and cons of current GSH-triggered prodrugs, we expect that this review will be a handful reference for prodrug design, and would provide a guidance for improving the properties of prodrugs and discovering novel trigger scaffolds for constructing GSH-triggered prodrugs.


Assuntos
Antineoplásicos , Pró-Fármacos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Estudos Retrospectivos , Antineoplásicos/farmacologia , Antineoplásicos/química , Glutationa/química , Linhagem Celular Tumoral
3.
Bioorg Chem ; 138: 106589, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37320912

RESUMO

Inhibiting thioredoxin reductase (TrxR) to disrupt the redox equilibrium and induce tumor cell apoptosis is a significant tumor therapeutic strategy. Piperine, a natural product from black pepper, has been demonstrated to suppress tumor cell proliferation by enhancing reactive oxygen species (ROS), subsequently leading to cell death. However, the development of Piperine as an active molecule is hampered by its weak cytotoxicity. To develop a compound with higher activity, we synthesized 22 Piperine analogs and evaluated their pharmacological properties. Ultimately, B5 was screened by the results of cytotoxicity and inhibition of TrxR activity. In contrast to Piperine, B5 had significant cytotoxicity with a 4-fold increase. The structure-activity relationship demonstrated that the introduction of an electron-withdrawing group into the benzene ring adjacent to the amino group, particularly in the meta-position, was positive and that shortening the olefin double bond had no appreciable impact on cytotoxicity. Further investigating the physiological activity of B5 in HeLa cells, we found that B5 selectively inhibits the activity of TrxR by binding to Sec residues on TrxR. B5 then induces cellular oxidative stress and finally leads to apoptosis. As a result, the study of B5 paved the way for further investigation into the modification and function of Piperine analogs as TrxR inhibitors.


Assuntos
Neoplasias , Tiorredoxina Dissulfeto Redutase , Humanos , Células HeLa , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Apoptose
4.
Sensors (Basel) ; 23(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37836939

RESUMO

The real-time monitoring of food freshness in refrigerators is of significant importance in detecting potential food spoiling and preventing serious health issues. One method that is commonly reported and has received substantial attention is the discrimination of food freshness via the tracking of volatile molecules. Nevertheless, the ambient environment of low temperature (normally below 4 °C) and high humidity (90% R.H.), as well as poor selectivity in sensing gas species remain the challenge. In this research, an integrated smart gas-tracking device is designed and fabricated. By applying pump voltage on the yttria-stabilized zirconia (YSZ) membrane, the oxygen concentration in the testing chamber can be manually tailored. Due to the working principle of the sensor following the mixed potential behavior, distinct differences in sensitivity and selectivity are observed for the sensor that operated at different oxygen concentrations. Typically, the sensor gives satisfactory selectivity to H2S, NH3, and C2H5OH at the oxygen concentrations of 10%, 30%, and 40%, respectively. In addition, an acceptable response/recovery rate (within 24 s) is also confirmed. Finally, a refrigerator prototype that includes the smart gas sensor is built, and satisfactory performance in discriminating food freshness status of fresh or semi-fresh is verified for the proposed refrigerator prototype. In conclusion, these aforementioned promising results suggest that the proposed integrated smart gas sensor could be a potential candidate for alarming food spoilage.


Assuntos
Temperatura Baixa , Alimentos , Umidade , Oxigênio
5.
J Xray Sci Technol ; 31(2): 373-391, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36641733

RESUMO

BACKGROUND: Dual-energy computed tomography (DECT) can reconstruct electron density ρe and effective atomic number Zeff distribution for material discrimination. Image-domain basis material decomposition (IBMD) method is a widely used DECT method. However, IBMD method cannot be used for mineral identification directly due to limitations of complex basis material determination, beam hardening artifacts, and inherent errors caused by approximate empirical formulas. OBJECTIVE: This study proposes an improved IBMD (IIBMD) method to overcome the above limitations. METHODS: In IIBMD method, the composition of basis material is optimized to obtain accurate decomposition coefficients, which enables accurate ρe and Zeff distribution. Moreover, the thickness of basis material is optimized to reduce the effect of beam hardening. Furthermore, two formulas in place of empirical formulas are proposed to calculate ρe and Zeff. Finally, a threshold technique is applied to separate different mineral phases. RESULTS: Numerical simulations and practical experiments using a photon-counting detector CT system are implemented to verify IIBMD method. Results show that the relative errors of ρe and Zeff for seven common minerals are down to 5%, lower than most of the existing DECT methods for rocks. Reasonable volume fraction results of mineral phases are thus obtained through threshold segmentation. CONCLUSIONS: This study demonstrates that the proposed IIBMD method has high practical value in mineralogical identification.


Assuntos
Tomografia Computadorizada por Raios X , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos
6.
Crit Rev Eukaryot Gene Expr ; 32(8): 69-80, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36017917

RESUMO

The problem facing gastric cancer treatment is the uncontrollable prognosis. Long noncoding RNAs (lncRNAs) are the current hotspot for gastric cancer prognostic markers. This study was targeted at determining THUMPD3-AS1 expression in gastric cancer, and then exploring whether THUMPD3-AS1 is associated with prognosis and its role in cancerous cell function. THUMPD3-AS1 expression levels were quantified in human tissues and cell lines. The prognostic biomarker potential of THUMPD3-AS1 was evaluated by Kaplan-Meier and multivariate Cox regression analyses. The biological impact of THUMPD3-AS1 in gastric cancer cells was investigated by WST-1, Tran-swell, and reactive oxygen species (ROS) accumulation assay. The binding between THUMPD3-AS1, miR-1252-3p and CXCL17 was verified by luciferase reporter assay and RNA pulled down assay. THUMPD3-AS1 was significantly decreased in gastric cancer tissues and cells by comparing them with normal ones. THUMPD3-AS1 was related to the advanced TNM stage, lymphatic infiltration, and vascular infiltration. Downregulated THUMPD3-AS1 was associated with reduced 5-year overall survival. Overexpression of THUMPD3-AS1 inhibits proliferation, migration, invasion and ROS accumulation of gastric cancer cells by regulation of miR-1252-3p and CXCL17. THUMPD3-AS1 could be a potent prognostic symbol for patients with gastric cancer. THUMPD3-AS1 provides a therapeutic potential for gastric cancer.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
7.
Analyst ; 147(5): 834-840, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35107099

RESUMO

Thioredoxins (Trxs) and glutaredoxins (Grxs) are the two major thiol-dependent reductases, participating in many important cellular events such as defense against oxidative stress, DNA synthesis and repair. Both Trxs and Grxs have diverse disulfide-containing substrates in the cells to exert their activities, with overlapping functions. Specific methods for measuring the intracellular overall activities of Trxs and Grxs are still lacking. Here we find that TRFS-green, a disulfide containing fluorescent probe which was used to detect thioredoxin reductase (TrxR) in mammalian cells, is a substrate of bacterial Trxs and Grxs, but not a substrate of bacterial TrxR and GSH. This property made TRFS-green work as a probe to measure the overall activities of Trxs and Grxs in bacterial cells. Using various E. coli Trx or Grx null mutant strains, the contribution of different Trxs and Grxs to cellular redox regulation has been clarified, judged by the reducibility towards TRFS-green. E. coli Grx2 and Grx3 unexpectedly exhibited higher activity in reducing the disulfide probe than the other redoxins. In addition, the bacterial disulfide reductase activity was detected to be affected in the ofloxacin bactericidal process. These results show that TRFS-green may be a useful tool for investigating bacterial redox regulation and demonstrating the critical role of E. coli Grxs in maintaining the bacterial intracellular redox balance.


Assuntos
Corantes Fluorescentes , Glutarredoxinas , Animais , Escherichia coli/genética , Glutarredoxinas/química , Glutarredoxinas/genética , Glutarredoxinas/metabolismo , Oxirredução , Tiorredoxina Dissulfeto Redutase , Tiorredoxinas/química , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
8.
J Biomed Inform ; 127: 103999, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35104642

RESUMO

The coronavirus disease (COVID-19) has claimed the lives of over 350,000 people and infected more than 173 million people worldwide, it triggers researchers from diverse fields are accelerating their research to help diagnostics, therapies, and vaccines. Researchers also publish their recent research progress through scientific papers. However, manually writing the abstract of a paper is time-consuming, and it increases the writing burden of the researchers. Abstractive summarization technique which automatically provides researchers reliable draft abstracts, can alleviate this problem. In this work, we propose a linguistically enriched SciBERT-based summarization model for COVID-19 scientific papers, named COVIDSum. Specifically, we first extract salient sentences from source papers and construct word co-occurrence graphs. Then, we adopt a SciBERT-based sequence encoder and a Graph Attention Networks-based graph encoder to encode sentences and word co-occurrence graphs, respectively. Finally, we fuse the above two encodings and generate an abstractive summary of each scientific paper. When evaluated on the publicly available COVID-19 open research dataset, the performance of our proposed model achieves significant improvement compared with other document summarization models.


Assuntos
COVID-19 , Humanos , Idioma , Editoração , SARS-CoV-2
9.
Plant Cell Rep ; 41(9): 1827-1841, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35732839

RESUMO

KEY MESSAGE: Our results confirmed that StATL2-like could interact with StCBFs and regulate plant growth. Meanwhile, StATL2-like acted as a negative regulator on low-temperature tolerance in plants. As important transcription factors for resisting many kinds of stresses, C-repeat-binding factors (CBF) play a key role in plant low-temperature tolerance by increasing COR genes expressions. Here, we report that StATL2-like, a RING-H2 E3 ubiquitin in Solanum tuberosum L., interacted with StCBF1 and StCBF4, respectively. AtATL2 is a highly homologous gene of StATL2-like in Arabidopsis thaliana. Under normal conditions, atl2 Arabidopsis mutant showed a growth inhibition phenotype while overexpressed StATL2-like in wild type Arabidopsis and atl2 mutant promoted plant growth. Besides, atl2 mutant had better low-temperature tolerance compared with wild type and StATL2-like transgenic lines which demonstrated that StATL2-like acted as a negatively regulator on low-temperature tolerance in plant. Moreover, atl2 mutant improved the scavenging capacity of reactive oxygen species (ROS) and alleviate the damage of photosynthetic system II (PSII) compared with StATL2-like transgenic lines under cold conditions. These results suggested a new component in CBF-dependent pathway to regulate plant growth and response to low-temperature stress in potato plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Solanum tuberosum , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Solanum tuberosum/metabolismo , Estresse Fisiológico
10.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144654

RESUMO

The majority of diseases' biomarkers are enzymes, and the regulation of enzymes is fundamental but crucial. Biological system disorders and diseases can result from abnormal enzymatic activity. Given the biological significance of enzymes, researchers have devised a plethora of tools to map the activity of particular enzymes in order to gain insight regarding their function and distribution. Near-infrared (NIR) fluorescence imaging studies on enzymes may help to better understand their roles in living systems due to their natural imaging advantages. We review the NIR fluorescent probe design strategies that have been attempted by researchers to develop NIR fluorescent sensors of enzymes, and these works have provided deep and intuitive insights into the study of enzymes in biological systems. The recent enzyme-activated NIR fluorescent probes and their applications in imaging are summarized, and the prospects and challenges of developing enzyme-activated NIR fluorescent probes are discussed.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Biomarcadores , Imagem Óptica/métodos
11.
Cell Biol Int ; 44(8): 1714-1726, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32339345

RESUMO

The dysregulation of proliferation and migration of vascular smooth muscle cells (VSMCs) contributes to atherosclerosis (AS) and accumulating reports indicate the crucial role of long noncoding RNA in AS. However, the role of small nucleolar RNA host gene 12 (SNHG12) in regulating the phenotypes of VSMCs and AS remains largely unknown. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was used to detect the expression levels of SNHG12 and miR-199a-5p in an in vivo AS model and VSMCs treated by oxidized low-density lipoprotein (ox-LDL). The proliferation ability, migration ability, and apoptosis of VSMCs were tested by cell counting kit-8, Transwell assay, and terminal deoxynucleotidyl transferase dUTP nick end labeling assay, respectively. StarBase database was used to predict the binding sites between miR-199a-5p and SNHG12. The interaction between miR-199a-5p and SNHG12 was validated by qRT-PCR, western blot, and luciferase reporter assay. Western blot was used to examine the effects of SNHG12 and miR-199a-5p on the expression of hypoxia-inducible factor 1α (HIF-1α). We found that the expression level of SNHG12 was significantly increased in the animal model and VSMCs treated by ox-LDL. Knockdown of SNHG12 suppressed the proliferation and migration abilities of VSMCs, while overexpression of SNHG12 had the opposite effects. Mechanically, we validated that miR-199a-5p was a target of SNHG12, and the target gene of miR-199a-5p, HIF-1α could be indirectly and positively regulated by SNHG12. In conclusion, SHNG12 targeting miR-199a-5p/HIF-1α contributed to the pathophysiological process of AS by regulating the phenotypes of VSMCs, and could be a potential therapy target for this disease.


Assuntos
Aterosclerose/genética , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Apoptose , Aterosclerose/metabolismo , Artérias Carótidas/citologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia
12.
Exp Cell Res ; 374(1): 69-75, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30439366

RESUMO

Type I natural killer T (NKT) cells are attractive candidates for cancer immunotherapy. In this study, we examined the characteristics of type I NKT cells in patients with adult B-cell acute lymphoblastic leukemia (ALL). We first identified type I NKT cells as Vα24-Jα18 and Vß11 double-positive CD3+ lymphocytes. Using this method, we found that the adult B-cell ALL patients presented significantly lower level of type I NKT cells than the age- and sex-matching control subjects. The expression of IL-21 by type I NKT cells was then examined using intracellular flow cytometry, which showed that with α-GalCer stimulation, the adult B-cell ALL patients presented significantly lower level of IL-21+ type I NKT cells than control subjects. By both flow cytometry and ELISA, we found that the vast majority of IL-21-expressing type I NKT cells expressed IL-21R, which was also reduced in adult B-cell ALL patients. Using an in vitro co-culture system, we demonstrated that IL-21R+, but not IL-21R-, type I NKT cells could promote the IFN-γ, granzyme B, and perforin expression by CD8 T cells in an IL-21-dependent fashion. This type I NKT cell-mediated stimulatory effect was reduced in adult B-cell ALL patients than in control subjects. In addition, we observed a positive correlation between the frequency of IL-21R+ type I NKT cells and the frequencies of IFN-γ-, granzyme B-, and perforin-expressing circulating CD8 T cells in adult B-cell ALL patients directly ex vivo. Overall, this study identified an IL-21-related impairment in type I NKT cells from adult B-cell ALL patients.


Assuntos
Células T Matadoras Naturais/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Adulto , Idoso , Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Interleucinas/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Receptores de Interleucina-21/metabolismo
13.
Cell Biochem Funct ; 38(7): 859-869, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32128852

RESUMO

Hepatocellular carcinoma (HCC) is one of the deadliest cancers. Multiple long non-coding RNAs (lncRNAs) are recently identified as crucial oncogenic factors or tumour suppressors. In this study, we explored the effects of LINC00174 on the progression of HCC. Expression levels of LINC00174 and microRNA-320 (miR-320) in HCC tissue samples were measured using quantitative real-time polymerase chain reaction (qRT-PCR). The association between pathological indices and LINC00174 was also analysed. Human HCC cell lines Hep3B and Huh7 were used as cell models. CCK-8 and bromodeoxyuridine (BrdU) assays were used to assess the effect of LINC00174 on HCC cell line proliferation. Flow cytometry was used to study the effect of LINC00174 on HCC apoptosis. Transwell assay was conducted to detect the effect of LINC00174 on migration and invasion. Furthermore, luciferase reporter assay and RNA immunoprecipitation (RIP) assay were used to confirm the binding relationship between miR-320 and LINC00174. Additionally, western blot was used to detect the regulatory function of LINC00174 on oncogene S100 calcium binding protein A10 (S100A10). We demonstrated that LINC00174 expression in HCC clinical samples was significantly increased and this was correlated with higher T stage. Its overexpression remarkably accelerated proliferation and metastasis of HCC cells while reduced apoptosis. Accordingly, knockdown of it suppressed the malignant phenotypes of HCC cells. Overexpression of LINC00174 significantly reduced the expression of miR-320 by sponging it, in turn enhanced the expression of S100A10. In conclusion, LINC00174 is a sponge of tumour suppressor miR-320, enhances the expression of S100A10 indirectly and functions as an oncogenic lncRNA in HCC. SIGNIFICANCE OF THE STUDY: LINC00174 is a novel lncRNA, whose function is rarely investigated. It is reported that it is oncogenic in colorectal cancer, while its role in HCC remains unclear. Herein, we report that LINC00174 is significantly up-regulated in HCC tissues and promotes the malignant phenotypes. We demonstrate that LINC00174 functions as a sponge for miR-320, increases the expression level of oncogene S100A10 in HCC. This study helps clarify the mechanism of HCC tumorigenesis and progression, and uncover the role of LINC00174 in human disease.


Assuntos
Anexina A2/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas S100/metabolismo , Anexina A2/química , Anexina A2/genética , Antagomirs/metabolismo , Sequência de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular , Movimento Celular , Proliferação de Células , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Proteínas S100/química , Proteínas S100/genética , Alinhamento de Sequência
14.
Sensors (Basel) ; 20(2)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31963213

RESUMO

In this paper, a kind of green triboelectric nano-generator based on natural degradable cellulose is proposed. Different kinds of regenerated cellulose composite layers are prepared by a blending doping method, and then assembled with poly(tetrafluoroethylene) (PTFE) thin films to form tribioelectric nanogenerator (TENG). The results show that the open circuit output voltage and the short circuit output current using a pure cellulose membrane is 7.925 V and 1.095 µA. After adding a certain amount of polyamide (PA6)/polyvinylidene fluoride (PVDF)/barium titanate (BaTiO3), the open circuit output voltage peak and the peak short circuit output current increases by 254.43% (to 20.155 V) and 548.04% (to 6.001 µA). The surface morphology, elemental composition and functional group of different cellulose layers are characterized by Scanning Electronic Microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and tested by the electrochemical analyze. Moreover, after multiple assembly and rectification processing, the electrical output performance shows that the peak value of open-circuit output voltage and the peak value of short circuit output current increases by 132.06% and 116.13%. Within 500 s of the charge-discharge test, the single peak charge reached 3.114 V, and the two peak charges reached 3.840 V. The results demonstrate that the nano-generator based on cellulose showed good stability and reliability, and the application and development of natural biomaterials represented by cellulose are greatly promoted in miniature electronic sensing area.

15.
Exp Cell Res ; 362(2): 287-292, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29174982

RESUMO

Diffuse large B cell lymphoma (DLBCL) is a common B cell malignancy with approximately 30% of patients present relapsed or refractory disease after first-line therapy. Research of further treatment options is needed. Cytotoxic CD4+ T cells express cytolytic molecules and have potential antitumor function. Here, we showed that the CD19+ cells from DLBCL patients presented significantly reduced expression of MHC II molecules than those from healthy controls. Three years after the first-line treatment, patients that presented relapsed disease had significantly lower MHC II expression on their CD19+ cells than patients who did not show recurrence. Examining cytotoxic CD4+ T cells show that DLBCL patients presented significantly elevated frequencies of granzyme A-, granzyme B-, and/or perforin-expressing cytotoxic CD4+ T cells. Also, frequency of cytotoxic CD4+ T cells in DLBCL patients was positively correlated with the MHC II expression level. Subsequently, the cytotoxic potential of CD4+ T cells against autologous CD19+ cells was investigated. We found that the cytotoxic potential of CD4+ T cells was highest in MHC II-high, intermediate in MHC II-mid, and lowest in MHC II-low patients. The percentage of MHC II-expressing viable CD19+ cells presented a significant reduction after longer incubation with cytotoxic CD4+ T cells, suggesting that cytotoxic CD4+ T cells preferentially eliminated MHC II-expressing CD19+ cells. Blocking MHC II on CD19+ cells significantly reduced the cytolytic capacity of CD4+ T cells. Despite these discoveries, the frequency of cytotoxic CD4+ T cells did not predict the clinical outcome of DLBCL patients. Together, these results demonstrated that cytotoxic CD4+ T cells presented an MHC II-dependent cytotoxic potential against autologous CD19+ cells and could potentially represent a future treatment option for DLBCL.


Assuntos
Antígenos CD19/imunologia , Linfócitos B/imunologia , Genes MHC da Classe II/genética , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Adulto , Idoso , Antígenos CD19/genética , Apoptose/genética , Linfócitos B/patologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/genética , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/imunologia , Genes MHC da Classe II/imunologia , Granzimas/genética , Humanos , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Perforina/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/transplante
16.
Exp Cell Res ; 369(2): 356-362, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29864401

RESUMO

Non-Hodgkin's lymphomas (NHLs) are a heterogeneous group of lymphoproliferative disorders. Mounting studies have suggested an involvement of angiogenesis signaling in NHLs progression and resistance to treatment. In this study, we investigated the cytotoxicity of CS2164, a novel receptor tyrosine kinase inhibitor selectively targeting VEGFR-2 and Aurora B in NHL cells. By in vitro culture system and in vivo xenograft model, we found that CS2164 significantly inhibited cell growth and abolished clonogenicity in NHL cells in a dose- and time-dependent manner. Meanwhile, CS2164 significantly induced NHL cells apoptosis and cell cycle arrest in G0/G1 phase. Moreover, CS2164 suppressed NHL cells growth and progression in an in vivo xenograft model. Mechanistically, CS2164-induced cytotoxicity was closely associated with inhibition of VEGFR2 and Aurora B as well as their downstream signaling cascades, including P38, ERK and H3 pathways. In conclusion, CS2164 exerts its cytotoxic effect via inhibition of proliferation and induction of apoptosis by modulating VEGFR2 and Aurora B signaling pathway, supporting a potential role for CS2164 in the treatment of NHLs.


Assuntos
Antineoplásicos/farmacologia , Linfoma não Hodgkin/tratamento farmacológico , Fenilenodiaminas/farmacologia , Quinolinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Aurora Quinase B/antagonistas & inibidores , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Naftalenos , Inibidores de Proteínas Quinases/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Ensaio Tumoral de Célula-Tronco , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Ann Hematol ; 97(11): 2137-2144, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30027435

RESUMO

Although the survival rate of diffuse large B cell lymphoma (DLBCL) has increased with years, there are still patients who do not achieve complete remission or who relapse, especially patients with activated B cell-like (ABC) DLBCL. Bortezomib, a proteasome inhibitor, has shown activity in diffuse large B cell lymphoma, especially in the subtype of ABC DLBCL. We conducted a meta-analysis to compare the efficacy and adverse events in bortezomib-containing regimens with standard R-CHOP regimen in treating DLBCL. Our results show that comparing to standard R-CHOP regimen, bortezomib-containing regimen could not prolong the survival in patients with ABC DLBCL. And patients who received bortezomib had a trend of higher risk with peripheral neuropathy, although there is no significant statistical difference.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Doenças do Sistema Nervoso Periférico , Anticorpos Monoclonais Murinos/uso terapêutico , Bortezomib/efeitos adversos , Bortezomib/uso terapêutico , Ciclofosfamida/uso terapêutico , Intervalo Livre de Doença , Doxorrubicina/uso terapêutico , Feminino , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Masculino , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/mortalidade , Prednisona/uso terapêutico , Rituximab , Taxa de Sobrevida , Vincristina/uso terapêutico
18.
Sensors (Basel) ; 15(9): 22811-25, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26371008

RESUMO

The quality of Computed Tomography (CT) images crucially depends on the precise knowledge of the scanner geometry. Therefore, it is necessary to estimate and calibrate the misalignments before image acquisition. In this paper, a Two-Piece-Ball (TPB) phantom is used to estimate a set of parameters that describe the geometry of a cone-beam CT system. Only multiple projections of the TPB phantom at one position are required, which can avoid the rotation errors when acquiring multi-angle projections. Also, a corresponding algorithm is derived. The performance of the method is evaluated through simulation and experimental data. The results demonstrated that the proposed method is valid and easy to implement. Furthermore, the experimental results from the Micro-CT system demonstrate the ability to reduce artifacts and improve image quality through geometric parameter calibration.


Assuntos
Tomografia Computadorizada de Feixe Cônico/normas , Processamento de Imagem Assistida por Computador/métodos , Microtomografia por Raio-X/normas , Algoritmos , Artefatos , Calibragem , Imagens de Fantasmas
19.
Front Oncol ; 14: 1333020, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38347846

RESUMO

Objective: To develop and validate a multiparametric MRI-based radiomics model for prediction of microsatellite instability (MSI) status in patients with endometrial cancer (EC). Methods: A total of 225 patients from Center I including 158 in the training cohort and 67 in the internal testing cohort, and 132 patients from Center II were included as an external validation cohort. All the patients were pathologically confirmed EC who underwent pelvic MRI before treatment. The MSI status was confirmed by immunohistochemistry (IHC) staining. A total of 4245 features were extracted from T2-weighted imaging (T2WI), contrast enhanced T1-weighted imaging (CE-T1WI) and apparent diffusion coefficient (ADC) maps for each patient. Four feature selection steps were used, and then five machine learning models, including Logistic Regression (LR), k-Nearest Neighbors (KNN), Naive Bayes (NB), Support Vector Machine (SVM), and Random Forest (RF), were built for MSI status prediction in the training cohort. Receiver operating characteristics (ROC) curve and decision curve analysis (DCA) were used to evaluate the performance of these models. Results: The SVM model showed the best performance with an AUC of 0.905 (95%CI, 0.848-0.961) in the training cohort, and was subsequently validated in the internal testing cohort and external validation cohort, with the corresponding AUCs of 0.875 (95%CI, 0.762-0.988) and 0.862 (95%CI, 0.781-0.942), respectively. The DCA curve demonstrated favorable clinical utility. Conclusion: We developed and validated a multiparametric MRI-based radiomics model with gratifying performance in predicting MSI status, and could potentially be used to facilitate the decision-making on clinical treatment options in patients with EC.

20.
ACS Nano ; 18(4): 3783-3790, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38236194

RESUMO

Significant advancements in electronic devices and integrated circuits have been facilitated by semiconducting single-walled carbon nanotubes (SWCNTs) sorted by conjugated polymers (CPs). However, the variety of CPs with single-chirality selectivity is limited, and the sorting results are strongly dependent on the chiral distribution of the starting materials. To address this, we develop an iterative strategy to achieve single-chirality SWCNT separation from aqueous to organic systems, based on a multistep tandem extraction technique that allows a gentle and nondestructive separation of surfactants from SWCNTs, ensuring an efficient system transfer. In parallel, we refined the iterative sorting process between CPs. Employing two starting materials with narrow diameter distributions, using three CPs, we successfully sorted out five single-chirality SWCNTs of the (9,5), (8,6), (10,5), (8,7), and (11,3) species in organic systems. This strategy bridges the gap between aqueous and organic separation systems, achieving efficient complementarity between them.

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