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1.
J Transl Med ; 22(1): 602, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943117

RESUMO

OBJECTIVE: This study aims to elucidate the functional role of IQGAP1 phosphorylation modification mediated by the SOX4/MAPK1 regulatory axis in developing pancreatic cancer through phosphoproteomics analysis. METHODS: Proteomics and phosphoproteomics data of pancreatic cancer were obtained from the Clinical Proteomic Tumor Analysis Consortium (CPTAC) database. Differential analysis, kinase-substrate enrichment analysis (KSEA), and independent prognosis analysis were performed on these datasets. Subtype analysis of pancreatic cancer patients was conducted based on the expression of prognostic-related proteins, and the prognosis of different subtypes was evaluated through prognosis analysis. Differential analysis of proteins in different subtypes was performed to identify differential proteins in the high-risk subtype. Clinical correlation analysis was conducted based on the expression of prognostic-related proteins, pancreatic cancer typing results, and clinical characteristics in the pancreatic cancer proteomics dataset. Functional pathway enrichment analysis was performed using GSEA/GO/KEGG, and most module proteins correlated with pancreatic cancer were selected using WGCNA analysis. In cell experiments, pancreatic cancer cells were grouped, and the expression levels of SOX4, MAPK1, and the phosphorylation level of IQGAP1 were detected by RT-qPCR and Western blot experiments. The effect of SOX4 on MAPK1 promoter transcriptional activity was assessed using a dual-luciferase assay, and the enrichment of SOX4 on the MAPK1 promoter was examined using a ChIP assay. The proliferation, migration, and invasion functions of grouped pancreatic cancer cells were assessed using CCK-8, colony formation, and Transwell assays. In animal experiments, the impact of SOX4 on tumor growth and metastasis through the regulation of MAPK1-IQGAP1 phosphorylation modification was studied by constructing subcutaneous and orthotopic pancreatic cancer xenograft models, as well as a liver metastasis model in nude mice. RESULTS: Phosphoproteomics and proteomics data analysis revealed that the kinase MAPK1 may play an important role in pancreatic cancer progression by promoting IQGAP1 phosphorylation modification. Proteomics analysis classified pancreatic cancer patients into two subtypes, C1 and C2, where the high-risk C2 subtype was associated with poor prognosis, malignant tumor typing, and enriched tumor-related pathways. SOX4 may promote the occurrence of the high-risk C2 subtype of pancreatic cancer by regulating MAPK1-IQGAP1 phosphorylation modification. In vitro cell experiments confirmed that SOX4 promoted IQGAP1 phosphorylation modification by activating MAPK1 transcription while silencing SOX4 inhibited the proliferation, migration, and invasion of pancreatic cancer cells by reducing the phosphorylation level of MAPK1-IQGAP1. In vivo, animal experiments further confirmed that silencing SOX4 suppressed the growth and metastasis of pancreatic cancer by reducing the phosphorylation level of MAPK1-IQGAP1. CONCLUSION: The findings of this study suggest that SOX4 promotes the phosphorylation modification of IQGAP1 by activating MAPK1 transcription, thereby facilitating the growth and metastasis of pancreatic cancer.


Assuntos
Progressão da Doença , Neoplasias Pancreáticas , Proteômica , Fatores de Transcrição SOXC , Proteínas Ativadoras de ras GTPase , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Fosfoproteínas/metabolismo , Fosforilação , Prognóstico , Proteínas Ativadoras de ras GTPase/metabolismo , Proteínas Ativadoras de ras GTPase/genética , Transdução de Sinais , Fatores de Transcrição SOXC/metabolismo , Fatores de Transcrição SOXC/genética
2.
Chemphyschem ; : e202400528, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945822

RESUMO

Electrochemical impedance spectroscopy (EIS), a conventional and alternating-current-(AC)-based technique for impedance measurement, is commonly used in battery diagnosis. However, it requires expensive equipment and demanding operating conditions and is complex and model-dependent in data analysis. Recently, novel direct current (DC) analytics have emerged as an alternative to EIS. They are simple yet powerful, being capable of revealing impedance information that traditionally could only be obtained through EIS and determining Li-ion diffusion coefficient. Besides, a complete EIS spectrum can be predicted based on constant current charging curves in the support of machine learning methods. This work highlights the similarities and discrepancies between DC techniques and EIS in the electrochemical analysis of Liion batteries. Looking ahead, DC techniques may be a promising substitute for EIS in future battery diagnosis, requiring simplified equipment while offering a deep understanding of battery impedance and its underlying electrochemical processes.

3.
Acta Biochim Biophys Sin (Shanghai) ; 56(4): 576-585, 2024 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-38433576

RESUMO

Poly ADP-ribose polymerase (PARP) inhibitor monotherapies are selectively effective in patients with pancreatic, breast, prostate, and ovarian cancers with BRCA1 mutations. Cancer patients with more frequent wild-type BRCA show poor responses to PARP inhibitors. Moreover, patients who are initially sensitive to these inhibitors eventually respond poorly to drugs. In the present study, we discover that abrogation of Kruppel-like factor 5 (KLF5) significantly inhibits homologous recombination, which is the main mechanism for DNA double-stranded repair. Furthermore, the downregulation of KLF5 expression promotes the DNA damage induced by olaparib and significantly reduces the IC 50 of the RARP inhibitor in pancreatic cancer cells. Overexpression of BRCA1 reverses the above effects caused by silencing of KLF5. Olaparib combined with a KLF5 inhibitor has an enhanced cytotoxic effect. Mechanistically, we identify BRCA1 as a KLF5 target gene. BRCA1 is positively correlated with KLF5 in PDAC tissue. Our results indicate that inhibition of KLF5 may induce BRCAness in a larger pancreatic cancer subset with proficient BRCA. The combination of KLF5 inhibitors and PARP inhibitors provides a novel treatment strategy to enhance the sensitivity of BRCA1-proficient pancreatic cancer to PARP inhibitors.


Assuntos
Antineoplásicos , Fatores de Transcrição Kruppel-Like , Neoplasias Pancreáticas , Humanos , Antineoplásicos/uso terapêutico , Proteína BRCA1/genética , Linhagem Celular Tumoral , Reparo do DNA , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Ovarianas/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico
4.
Angew Chem Int Ed Engl ; 63(7): e202307802, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-37515479

RESUMO

Lithium (Li) metal batteries (LMBs) are the "holy grail" in the energy storage field due to their high energy density (theoretically >500 Wh kg-1 ). Recently, tremendous efforts have been made to promote the research & development (R&D) of pouch-type LMBs toward practical application. This article aims to provide a comprehensive and in-depth review of recent progress on pouch-type LMBs from full cell aspect, and to offer insights to guide its future development. It will review pouch-type LMBs using both liquid and solid-state electrolytes, and cover topics related to both Li and cathode (including LiNix Coy Mn1-x-y O2 , S and O2 ) as both electrodes impact the battery performance. The key performance criteria of pouch-type LMBs and their relationship in between are introduced first, then the major challenges facing the development of pouch-type LMBs are discussed in detail, especially those severely aggravated in pouch cells compared with coin cells. Subsequently, the recent progress on mechanistic understandings of the degradation of pouch-type LMBs is summarized, followed with the practical strategies that have been utilized to address these issues and to improve the key performance criteria of pouch-type LMBs. In the end, it provides perspectives on advancing the R&Ds of pouch-type LMBs towards their application in practice.

5.
Nat Mater ; 19(4): 428-435, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31932670

RESUMO

All-solid-state Li-ion batteries promise safer electrochemical energy storage with larger volumetric and gravimetric energy densities. A major concern is the limited electrochemical stability of solid electrolytes and related detrimental electrochemical reactions, especially because of our restricted understanding. Here we demonstrate for the argyrodite-, garnet- and NASICON-type solid electrolytes that the favourable decomposition pathway is indirect rather than direct, via (de)lithiated states of the solid electrolyte, into the thermodynamically stable decomposition products. The consequence is that the electrochemical stability window of the solid electrolyte is notably larger than predicted for direct decomposition, rationalizing the observed stability window. The observed argyrodite metastable (de)lithiated solid electrolyte phases contribute to the (ir)reversible cycling capacity of all-solid-state batteries, in addition to the contribution of the decomposition products, comprehensively explaining solid electrolyte redox activity. The fundamental nature of the proposed mechanism suggests this is a key aspect for solid electrolytes in general, guiding interface and material design for all-solid-state batteries.

6.
Int J Clin Oncol ; 26(1): 135-144, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32959232

RESUMO

BACKGROUND: Inflammatory factors and fasting blood glucose were verified to be associated with the prognosis of pancreatic ductal adenocarcinoma. The goal of this study is to confirm the prognostic role of preoperative blood glucose to lymphocyte ratio for patients with resected pancreatic ductal adenocarcinoma. METHODS: A total of 259 pancreatic ductal adenocarcinoma patients were enrolled and randomly divided into training cohort and validation cohort. The training cohort was used to generate an optimal cutoff value and the validation cohort was used to further validate the model. RESULTS: A total of 259 patients were incorporated in this study and randomly divided into the training cohort (n = 130, 1/2 of 259) and the validation cohort (129, 1/2 of 259). The optimal cutoff value of glucose to lymphocyte ratio was calculated to be 3.47 for overall survival. Cox regression analysis found that preoperative blood glucose to lymphocyte ratio was independent risk factor (p = 0.040) for overall survival. Prognostic values of glucose to lymphocyte ratio on overall survival were observed in younger male patients with pancreatic body and tail cancer, American Joint Committee on Cancer 8th N1 stage, without microvascular and peripancreatic fat invasion, and Carbohydrate antigen 19-9 higher than 200 U/ml. A prognostic prediction model of overall survival was designed and presented in nomogram. CONCLUSION: Preoperative blood glucose to lymphocyte ratio is an independent biomarker to predict the overall survival for pancreatic ductal adenocarcinoma patients who underwent curative resection.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/cirurgia , Glucose , Humanos , Linfócitos , Masculino , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos
7.
Jpn J Clin Oncol ; 50(6): 679-687, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32372083

RESUMO

OBJECTIVE: The aim of delivering radiotherapy for pancreatic ductal adenocarcinoma patients was to sterilize vessel margin, increase R0 resection rate and delay local progression. Whether preoperative radiotherapy could prolong overall survival of surgical candidates remained unknown. METHODS: Pancreatic ductal adenocarcinoma patients receiving radical resection from surveillance, epidemiology and end result database were enrolled. Propensity score matching was conducted to balance difference in baseline characteristics, and survival analyses were performed to compare overall survival between preoperative radiotherapy and upfront resection groups. Cox proportional hazard regression model and subgroup analyses were utilized to identify prognostic factors. RESULTS: A total of 11 665 and 597 pancreatic ductal adenocarcinoma patients receiving upfront resection and preoperative radiotherapy followed by resection from 2004 to 2016 were identified, respectively, while baseline characteristics were distinct between groups. After propensity score matching, preoperative radiotherapy was not associated with better overall survival (upfront resection vs preoperative radiotherapy, 26 vs 27 months). Subgroup analyses showed that preoperative radiotherapy was a protective factor in pT4 (hazard ratio = 0.64, 95% confidence interval: 0.47-0.88) but a negative predictor in pT1 (hazard ratio = 1.79, 95% confidence interval: 1.08-2.97) patient populations. Survival analyses showed that preoperative radiotherapy improved overall survival of patients with pT4 stage (upfront resection vs preoperative radiotherapy, 19 vs 25 months) and involvement of celiac axis, superior mesenteric artery and aorta (upfront resection vs preoperative radiotherapy, 20 vs 27 months), while preoperative radiotherapy was associated with worse overall survival in patients with pT1 tumor (upfront resection vs preoperative radiotherapy, 39 vs 24 months). CONCLUSION: Preoperative radiotherapy could improve survival of resected pancreatic ductal adenocarcinoma patients with pT4 stage or with celiac axis, superior mesenteric artery and aorta invasion.


Assuntos
Protocolos Antineoplásicos , Carcinoma Ductal Pancreático/radioterapia , Neoplasias Pancreáticas/radioterapia , Idoso , Carcinoma Ductal Pancreático/cirurgia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/cirurgia , Pontuação de Propensão , Modelos de Riscos Proporcionais , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
8.
Biochem Biophys Res Commun ; 505(2): 569-577, 2018 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-30274773

RESUMO

The metastatic potential of malignant tumor has been shown to be correlated with the increased expression of tri- and tetra-antennary ß1,6-N-acetylglucosamine (ß1,6-GlcNAc) N-glycans. In this study, We found that GnT-V expression was negatively correlated with receptor protein tyrosine phosphatase type µ(RPTPµ) in human glioma tissues. To study whether RPTPµ is a novel substance of GnT-V which further affect RPTPµ's downstream dephosphorylation function, we preform lentiviral infection with GnT-V gene to construct stably transfected GnT-V glial cell lines. We found RPTPµ undergone severer cleavage in GnT-V transfected glioma cells compare to Mock cells. RPTPµ intracellular domain fragments increased while ß1,6-GlcNAc-branched N-glycans increased, in consistent with the decrease of RPTPµ's catalytic activity. The results showed that abnormal glycosylation could decrease the phosphorylation activity of PTP µ, and affect PLCγ-PKC pathways. Both protease inhibitor Furin and N-glycan biosynthesis inhibitor swainsonine could decrease cell mobility in GnT-V-U87 transfectants and other glioma cell lines. All results above suggest increased post-translational modification of RPTPµ N-glycans by GnT-V attenuates its tyrosine phosphatase activity and promotes glioma cell migration through PLCγ-PKC pathways, and that the ß1,6-GlcNAc-branched N-glycans of RPTPµ play a crucial role in glioma invasivity.


Assuntos
Glioma/enzimologia , N-Acetilglucosaminiltransferases/metabolismo , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/metabolismo , beta-Glucanas/metabolismo , Movimento Celular , Adesões Focais , Glioma/fisiopatologia , Glicosilação , Humanos , Fosfolipase C gama/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais
9.
Jpn J Clin Oncol ; 48(6): 535-541, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718363

RESUMO

OBJECTIVE: To compare efficacy and safety of nabpaclitaxel plus S-1 (AS) with gemcitabine plus S-1 (GS) as first-line treatment for metastatic pancreatic cancer. METHODS: We conducted a retrospective cohort, single-institution analysis by reviewing medical records of 38 patients who received either AS (nabpaclitaxel 125 mg/m2 on Days 1, 8 and S-1 80 mg/m2 on Days 1 to 14) or GS (gemcitabine 1000 mg/m2 on Days 1, 8 and S-1 80 mg/m2 on Days 1 to 14) chemotherapy. RESULTS: AS was associated with a prolonged median time to progression (TTP; 7.1 months, 95% CI, 4.5-9.7 vs. 3.6 months, 95% CI, 1.8-5.4; P value = 0.022) and improved median overall survival (OS; 10.2 months, 95% CI, 9.1-11.3 vs. 6 months, 95% CI, 4.2-7.8; P value <0.001) compared with GS. In cox proportional hazards model, treatment regimen was the only variable to be significantly associated with improvements in both TTP and OS. Subgroup analyses based on HER2 expression showed that AS seemed to have better outcome of OS in HER2 positive patients (HR = 0.168; 95% CI, 0.022-1.27; P value = 0.084). Hematological adverse events were commonly seen in both group (12.5% and 22.7%, GS and AS group, Grade 3 or 4; P value = 0.675) while AS got increased risk of sensory neuropathy (6 of 22 patients in AS, 27.3% vs. 0 of 16 patients in GS, all grade; P value = 0.03). CONCLUSIONS: AS could be an effective treatment regimen for metastatic pancreatic cancer under surveillance of toxicity.


Assuntos
Albuminas/efeitos adversos , Albuminas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Ácido Oxônico/efeitos adversos , Ácido Oxônico/uso terapêutico , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/secundário , Tegafur/efeitos adversos , Tegafur/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Pancreáticas/patologia , Cooperação do Paciente , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do Tratamento , Gencitabina
10.
J Cell Biochem ; 118(6): 1423-1431, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27864899

RESUMO

Cadherin is crucial for cell-cell adhesion and N-glycosylation of N-cadherin has been implicated in the process of mammary, renal, and ovarian carcinogenesis. However, whether N-glycosylation of N-cadherin plays a role in glioma remains unknown. Previous studies had indicated that N-glycosylation could occur at three asparagine residues of N-cadherin. By generating and over-expressing N-glycosylation-deficient N-cadherin mutants in the human glioma cell lines SHG66 and U87, we found that mutation of N402 but not of the other potentially N-glycosylated residues destabilized N-cadherin and led to its ubiquitylation and subsequent proteasomal degradation. Furthermore, destabilized N-cadherin inhibited cadherin-mediated cell-cell adhesion and promoted cell migration. Our findings reveal that N-glycosylation controls N-cadherin stability and plays a role in glioma migration. J. Cell. Biochem. 118: 1423-1431, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Antígenos CD/química , Antígenos CD/metabolismo , Asparagina/química , Caderinas/química , Caderinas/metabolismo , Glioma/metabolismo , Antígenos CD/genética , Asparagina/genética , Caderinas/genética , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Glioma/genética , Glicosilação , Humanos , Mutação , N-Acetilglucosaminiltransferases/metabolismo , Estabilidade Proteica
11.
Biochem Biophys Res Commun ; 482(4): 1455-1461, 2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-27965091

RESUMO

Receptor-like protein tyrosine phosphatase alpha (RPTPα or PTPα), a type I transmembrane glycoprotein with complex N-glycans, executes multifunction roles on cell behaviors. However, its effect on tumorigenesis and metastasis remains controversial. In this study, PTPα is identified as a novel substrate of N-Acetylglucosaminyltransferase V (GnT-V). Immunofluorescence results showed that addition of ß1,6 GlcNAc branches on PTPα enhanced PTPα's cytomembrane assemble in GnT-V-MCF-7 compared with Mock-MCF-7 (MCF7 cells transfected with the vector pcDNA3). Then we found the alleviating degradation of PTPα was observed in GnT-V-MCF-7 while PTPα in Mock-MCF-7 was prone to quick degradation. Increased cell-surface retention subsequently enhanced PTPα's catalytic activity on the dephosphorylation of Src kinase at Tyr529 and promoted focal adhesion formation and mature. Therefore, our findings could provide an insight into the molecular mechanism of how GnT-V promoted cell migration, suggesting that PTPα could be one of factors regulating promote migration of breast cancer cell.


Assuntos
Adesões Focais/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Proteínas Tirosina Fosfatases Classe 4 Semelhantes a Receptores/metabolismo , Neoplasias da Mama/metabolismo , Carcinogênese , Catálise , Linhagem Celular Tumoral , Movimento Celular , Feminino , Glicosilação , Humanos , Integrina beta1/metabolismo , Lectinas/química , Células MCF-7 , Metástase Neoplásica , Fosforilação , Plasmídeos/metabolismo , Polissacarídeos/química , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Quinases da Família src/metabolismo
12.
J Appl Toxicol ; 36(4): 543-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26817529

RESUMO

Immune cells play an important role in recognizing and removing foreign objects, such as nanoparticles. Among various parameters, surface coatings of nanoparticles are the first contact with biological system, which critically affect nanoparticle interactions. Here, surface coating effects on nanoparticle cellular uptake, toxicity and ability to trigger immune response were evaluated on a human monocyte cell line using iron oxide nanoparticles. The cells were treated with nanoparticles of three types of coatings (negatively charged polyacrylic acid, positively charged polyethylenimine and neutral polyethylene glycol). The cells were treated at various nanoparticle concentrations (5, 10, 20, 30, 50 µg ml(-1) or 2, 4, 8, 12, 20 µg cm(-2)) with 6 h incubation or treated at a nanoparticle concentration of 50 µg ml(-1) (20 µg cm(-2)) at different incubation times (6, 12, 24, 48 or 72 h). Cell viability over 80% was observed for all nanoparticle treatment experiments, regardless of surface coatings, nanoparticle concentrations and incubation times. The much lower cell viability for cells treated with free ligands (e.g. ~10% for polyethylenimine) suggested that the surface coatings were tightly attached to the nanoparticle surfaces. The immune responses of cells to nanoparticles were evaluated by quantifying the expression of toll-like receptor 2 and tumor necrosis factor-α. The expression of tumor necrosis factor-α and toll-like receptor 2 were not significant in any case of the surface coatings, nanoparticle concentrations and incubation times. These results provide useful information to select nanoparticle surface coatings for biological and biomedical applications.


Assuntos
Compostos Férricos/toxicidade , Monócitos/efeitos dos fármacos , Nanopartículas/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Compostos Férricos/química , Humanos , Imunidade Inata/efeitos dos fármacos , Monócitos/citologia , Monócitos/metabolismo , Nanopartículas/química , Polietilenoglicóis/química , Propriedades de Superfície , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
13.
Int J Mol Sci ; 16(10): 24174-93, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26473847

RESUMO

Increasing use of iron oxide nanoparticles in medicine and environmental remediation has led to concerns regarding exposure of these nanoparticles to the public. However, limited studies are available to evaluate their effects on the environment, in particular on plants and food crops. Here, we investigated the effects of positive (PC) and negative (NC) charged iron oxide (Fe2O3) nanoparticles (IONPs) on the physiology and reproductive capacity of Arabidopsis thaliana at concentrations of 3 and 25 mg/L. The 3 mg/L treated plants did not show evident effects on seeding and root length. However, the 25 mg/L treatment resulted in reduced seedling (positive-20% and negative-3.6%) and root (positive-48% and negative-negligible) length. Interestingly, treatment with polyethylenimine (PEI; IONP-PC coating) also resulted in reduced root length (39%) but no change was observed with polyacrylic acid (PAA; IONP-NC coating) treatment alone. However, treatment with IONPs at 3 mg/L did lead to an almost 5% increase in aborted pollen, a 2%-6% reduction in pollen viability and up to an 11% reduction in seed yield depending on the number of treatments. Interestingly, the treated plants did not show any observable phenotypic changes in overall size or general plant structure, indicating that environmental nanoparticle contamination could go dangerously unnoticed.


Assuntos
Arabidopsis , Compostos Férricos/farmacologia , Germinação/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Raízes de Plantas/efeitos dos fármacos , Sementes/efeitos dos fármacos , Resinas Acrílicas/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/embriologia , Arabidopsis/crescimento & desenvolvimento , Transporte Biológico/fisiologia , Exposição Ambiental , Pólen/efeitos dos fármacos , Polietilenoimina/farmacologia , Reprodução/efeitos dos fármacos , Plântula/efeitos dos fármacos
14.
Int J Mol Sci ; 16(12): 30251-68, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26694381

RESUMO

Iron oxide nanoparticles (NPs) are commonly utilized for biomedical, industrial, and commercial applications due to their unique properties and potential biocompatibility. However, little is known about how exposure to iron oxide NPs may affect susceptible populations such as pregnant women and developing fetuses. To examine the influence of NP surface-charge and dose on the developmental toxicity of iron oxide NPs, Crl:CD1(ICR) (CD-1) mice were exposed to a single, low (10 mg/kg) or high (100 mg/kg) dose of positively-charged polyethyleneimine-Fe2O3-NPs (PEI-NPs), or negatively-charged poly(acrylic acid)-Fe2O3-NPs (PAA-NPs) during critical windows of organogenesis (gestation day (GD) 8, 9, or 10). A low dose of NPs, regardless of charge, did not induce toxicity. However, a high exposure led to charge-dependent fetal loss as well as morphological alterations of the uteri (both charges) and testes (positive only) of surviving offspring. Positively-charged PEI-NPs given later in organogenesis resulted in a combination of short-term fetal loss (42%) and long-term alterations in reproduction, including increased fetal loss for second generation matings (mice exposed in utero). Alternatively, negatively-charged PAA-NPs induced fetal loss (22%) earlier in organogenesis to a lesser degree than PEI-NPs with only mild alterations in offspring uterine histology observed in the long-term.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Compostos Férricos/toxicidade , Nanopartículas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/patologia , Reprodução/efeitos dos fármacos , Animais , Cesárea , Feminino , Fertilidade/efeitos dos fármacos , Feto/efeitos dos fármacos , Tamanho da Ninhada de Vivíparos , Masculino , Camundongos , Gravidez , Propriedades de Superfície , Testículo/efeitos dos fármacos , Testículo/patologia , Fatores de Tempo , Útero/efeitos dos fármacos , Útero/patologia
15.
Anal Chem ; 86(16): 8496-503, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25075547

RESUMO

A new matrix-assisted laser desorption ionization (MALDI) mass spectrometry matrix is proposed for molecular mass and structural determination of glycans. This matrix contains an iron oxide nanoparticle (NP) core with gluthathione (GSH) molecules covalently bound to the surface. As demonstrated for the monosaccharide glucose and several larger glycans, the mass spectra exhibit good analyte ion intensities and signal-to-noise ratios, as well as an exceptionally clean background in the low mass-to-charge (m/z) region. In addition, abundant in-source decay (ISD) occurs when the laser power is increased above the ionization threshold; this indicates that the matrix provides strong energy transfer to the sample. For five model glycans, ISD produced extensive glycosidic and cross-ring cleavages in the positive ion mode from singly charged precursor ions with bound sodium ions. Linear, branched, and cyclic glycans were employed, and all were found to undergo abundant fragmentation by ISD. (18)O labeling was used to clarify m/z assignment ambiguities and showed that the majority of the fragmentation originates from the nonreducing ends of the glycans. Studies with a peracetylated glycan indicated that abundant ISD fragmentation occurs even in the absence of hydroxyl groups. The ISD product ions generated using this new matrix should prove useful in the sequencing of glycans.


Assuntos
Compostos Férricos/química , Glutationa/química , Nanopartículas/química , Polissacarídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Nanopartículas/ultraestrutura , Razão Sinal-Ruído
16.
Adv Mater ; 36(18): e2311655, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38240357

RESUMO

Facile synthesis of porous carbon with high yield and high specific surface area (SSA) from low-cost molecular precursors offers promising opportunities for their industrial applications. However, conventional activation methods using potassium and sodium hydroxides or carbonates suffer from low yields (<20%) and poor control over porosity and composition especially when high SSAs are targeted (>2000 m2 g-1) because nanopores are typically created by etching. Herein, a non-etching activation strategy is demonstrated using cesium salts of low-cost carboxylic acids as the sole precursor in producing porous carbons with yields of up to 25% and SSAs reaching 3008 m2 g-1. The pore size and oxygen content can be adjusted by tuning the synthesis temperature or changing the molecular precursor. Mechanistic investigation unravels the non-classical role of cesium as an activating agent. The cesium compounds that form in situ, including carbonates, oxides, and metallic cesium, have extremely low work function enabling electron injection into organic/carbonaceous framework, promoting condensation, and intercalation of cesium ions into graphitic stacks forming slit pores. The resulting porous carbons deliver a high capacity of 252 mAh g-1 (567 F g-1) and durability of 100 000 cycles as cathodes of Zn-ion capacitors, showing their potential for electrochemical energy storage.

17.
J Gastrointest Oncol ; 15(1): 22-32, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38482225

RESUMO

Background: Gastric cancer (GC) is a common tumors in the digestive tract, and effective treatment methods are still lacking. Bone morphogenetic protein 6 (BMP6) is closely related to the occurrence and development of various tumors, but its relevance to GC is still unclear. The aim of the study was to explore the relationship between BMP6 and the occurrence and development of GC. Methods: In this study, we investigated the relationship between BMP6 and the prognosis of GC patients using bioinformatics technology and clinical tissue samples. We also explored the connection between BMP6 and the biological behavior of GC cells through molecular biology experiments and relevant in vivo animal experiments. Finally, we examined the mechanisms by which BMP6 inhibits the onset and progression of GC. Results: Through analysis of The Cancer Genomics Atlas (TCGA) database, we observed that BMP6 is expressed at low levels in GC, and its low expression is associated with a poor prognosis in GC patients. Cell experiments demonstrated that BMP6 expression can influence the proliferation of GC cells both in vitro and in vivo. Furthermore, we discovered that BMP6 is linked to the nuclear factor-κB (NF-κB) pathway, and subsequent experiments confirmed that BMP6 can inhibit the biological activity of GC cells by activating the NF-κB pathway. Conclusions: Our findings suggest that BMP6 is a potential prognostic biomarker in GC and can regulate the biological activity of GC cells through the NF-κB pathway. BMP6 may serve as a promising therapeutic target for GC, and our study introduces novel ideas for the prevention and treatment of this disease.

18.
Oncol Lett ; 27(4): 161, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38449794

RESUMO

Patients with advanced pancreatic cancer (PC) need a cost-effective treatment regimen. The present study was designed to compare the efficacy and safety of nab-paclitaxel plus S-1 (AS) and gemcitabine plus S-1 (GS) regimens in patients with chemotherapy-naïve advanced PC. In this open-label, multicenter, randomized study named AvGmPC, eligible patients with chemotherapy-naïve advanced PC were randomly assigned (1:1) to receive AS (125 mg/m2 nab-paclitaxel, days 1 and 8; 80-120 mg S-1, days 1-14) or GS (1,000 mg/m2 gemcitabine, days 1 and 8; 80-120 mg S-1, days 1-14). The treatment was administered every 3 weeks until intolerable toxicity or disease progression occurred. The primary endpoint was progression-free survival (PFS). Between December 2018 and March 2022, 101 of 106 randomized patients were treated and evaluated for analysis (AS, n=49; GS, n=52). As of the data cutoff, the median follow-up time was 11.37 months [95% confidence interval (CI), 9.31-13.24]. The median PFS was 7.16 months (95% CI, 5.19-12.32) for patients treated with AS and 6.41 months (95% CI, 3.72-8.84) for patients treated with GS (HR=0.78; 95% CI, 0.51-1.21; P=0.264). The AS regimen showed a slightly improved overall survival (OS; 13.27 vs. 10.64 months) and a significantly improved ORR (44.90 vs. 15.38%; P=0.001) compared with the GS regimen. In the subgroup analyses, PFS and OS benefits were observed in patients treated with the AS regimen who had KRAS gene mutations and high C-reactive protein (CRP) levels (≥5 mg/l). The most common grade ≥3 adverse events were neutropenia, anemia and alopecia in the two groups. Thrombocytopenia occurred more frequently in the GS group than in the AS group. While the study did not meet the primary endpoint, the response benefit observed for AS may be suggestive of meaningful clinical activity in this population. In particular, promising survival benefits were observed in the subsets of patients with KRAS gene mutations and high CRP levels, which is encouraging and warrants further investigation. This trial was retrospectively registered as ChiCTR1900024588 on July 18, 2019.

19.
ACS Appl Mater Interfaces ; 15(1): 795-805, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36542687

RESUMO

Niobium pentoxides have received considerable attention and are promising anode materials for lithium-ion batteries (LIBs), due to their fast Li storage kinetics and high capacity. However, their cycling stability and rate performance are still limited owing to their intrinsic insulating properties and structural degradation during charging and discharging. Herein, a series of mesoporous Nb2O5@TiO2 core-shell spherical heterostructures have been prepared for the first time by a sol-gel method and investigated as anode materials in LIBs. Mesoporosity can provide numerous open and short pathways for Li+ diffusion; meanwhile, heterostructures can simultaneously enhance the electronic conductivity and thus improve the rate capability. The TiO2 coating layer shows robust crystalline skeletons during repeated lithium insertion and extraction processes, retaining high structural integrity and, thereby, enhancing cycling stability. The electrochemical behavior is strongly dependent on the thickness of the TiO2 layer. After optimization, a mesoporous Nb2O5@TiO2 core-shell structure with a ∼13 nm thick TiO2 layer delivers a high specific capacity of 136 mA h g-1 at 5 A g-1 and exceptional cycling stability (88.3% retention over 1000 cycles at 0.5 A g-1). This work provides a facile strategy to obtain mesoporous Nb2O5@TiO2 core-shell spherical structures and underlines the importance of structural engineering for improving the performance of battery materials.

20.
Front Oncol ; 13: 1109068, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37534251

RESUMO

Background: While adjuvant chemotherapy has been established as standard practice following radical resection of pancreatic ductal adenocarcinoma (PDAC), the role of adjuvant radiation therapy (RT) and which patients may benefit remains unclear. Methods: This retrospective study included PDAC patients who received pancreatic surgery from April 2012 to December 2019 in Zhongshan Hospital Fudan University. Patients with carcinoma in situ, distant metastasis, and without adjuvant chemotherapy were excluded. Cox proportional hazards modeling of survival were constructed to find potential prognostic factors. Propensity score matching (PSM) and exploratory subgroup analyses were used to create a balanced covariate distribution between groups and to investigate therapeutic effect of radiotherapy in certain subgroups. Results: A total of 399 patients were finally included, 93 of them receiving adjuvant chemoradiotherapy (C+R+) and 306 of them receiving chemotherapy only. Patients in C+R+ group were more likely to be male patients with T3-4 disease. Lymph node metastases was the only negative prognostic factor associated with overall survival (OS). Additional adjuvant RT was not associated with an OS benefit both before and after PSM. Surprisingly, a trend towards improved OS with RT among patients with either T4, N2 disease or R1 resection becomes significant in patients alive more than 1 year after surgery. Conclusion: Adjuvant RT was not associated with an OS benefit across all patients, though did show a possible OS benefit for the subgroup with T4N2 disease or R1 resection at 1 year after surgery.

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