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1.
Vaccine ; 42(6): 1342-1351, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38310017

RESUMO

Toxoplasma gondii (T. gondii) is one of the most common pathogenic protozoa in the world, and causes toxoplasmosis, which in varying degrees causes significant economic losses and poses a serious public health challenge globally. To date, the development of an effective vaccine for human toxoplasmosis remains a challenge. Given that T.gondii calcium-dependent protein kinase 3 (CDPK3), dense granule protein 35 (GRA35) and rhoptry organelle protein 46 (ROP46) play key roles during Toxoplasma gondii invasion of host cells, we developed a protein vaccine cocktail including these proteins and validated its protective efficacy. The specific protective effects of vaccine on mice were analyzed by measuring serum antibodies, cytokines, splenocyte proliferation, the percentage of CD4+ and CD8+ T-lymphocytes, survival rate, and parasite cyst burden. The results showed that mice vaccinated with a three-protein cocktail produced the highest levels of immune protein antibodies to IgG, and high levels of IFN-γ, IL-2, IL-4, and IL-10 compared to other mice vaccinated with two proteins. In addition, CD4+ and CD8+ T cell percentages were significantly elevated. Compared to the control groups, mice vaccinated with the three-protein cocktail survived significantly longer after acute infection with T. gondii and had significantly fewer cysts after chronic infection. These results demonstrated that a cocktail vaccine of TgCDPK3, TgGRA35, and TgROP46 can effectively induce cellular and humoral immune responses with good protective effects in mice, indicating its potential as vaccine candidates for toxoplasmosis.


Assuntos
Proteínas Quinases , Vacinas Protozoárias , Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Vacinas de DNA , Animais , Camundongos , Humanos , Camundongos Endogâmicos BALB C , Toxoplasmose/prevenção & controle , Proteínas de Protozoários/genética , Organelas , Anticorpos Antiprotozoários , Toxoplasmose Animal/prevenção & controle
2.
J Colloid Interface Sci ; 660: 869-884, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277843

RESUMO

Infiltration and activation of intratumoral T lymphocytes are critical for immune checkpoint blockade (ICB) therapy. Unfortunately, the low tumor immunogenicity and immunosuppressive tumor microenvironment (TME) induced by tumor metabolic reprogramming cooperatively hinder the ICB efficacy. Herein, we engineered a lactate-depleting MOF-based catalytic nanoplatform (LOX@ZIF-8@MPN), encapsulating lactate oxidase (LOX) within zeolitic imidazolate framework-8 (ZIF-8) coupled with a coating of metal polyphenol network (MPN) to reinforce T cell response based on a "two birds with one stone" strategy. LOX could catalyze the degradation of the immunosuppressive lactate to promote vascular normalization, facilitating T cell infiltration. On the other hand, hydrogen peroxide (H2O2) produced during lactate depletion can be transformed into anti-tumor hydroxyl radical (•OH) by the autocatalytic MPN-based Fenton nanosystem to trigger immunogenic cell death (ICD), which largely improved the tumor immunogenicity. The combination of ICD and vascular normalization presents a better synergistic immunopotentiation with anti-PD1, inducing robust anti-tumor immunity in primary tumors and recurrent malignancies. Collectively, our results demonstrate that the concurrent depletion of lactate to reverse the immunosuppressive TME and utilization of the by-product from lactate degradation via cascade catalysis promotes T cell response and thus improves the effectiveness of ICB therapy.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Humanos , Ácido Láctico/farmacologia , Estruturas Metalorgânicas/farmacologia , Peróxido de Hidrogênio/farmacologia , Linfócitos T , Imunoterapia , Linhagem Celular Tumoral , Microambiente Tumoral
3.
ACS Nano ; 18(5): 4189-4204, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38193384

RESUMO

cGAS-STING signaling plays a critical role in radiotherapy (RT)-mediated immunomodulation. However, RT alone is insufficient to sustain STING activation in tumors under a safe X-ray dose. Here, we propose a radiosensitization cooperated with cGAS stimulation strategy by engineering a core-shell structured nanosized radiosensitizer-based cGAS-STING agonist, which is constituted with the hafnium oxide (HfO2) core and the manganese oxide (MnO2) shell. HfO2-mediated radiosensitization enhances immunogenic cell death to afford tumor associated antigens and adequate cytosolic dsDNA, while the GSH-degradable MnO2 sustainably releases Mn2+ in tumors to improve the recognition sensitization of cGAS. The synchronization of sustained Mn2+ supply with cumulative cytosolic dsDNA damage synergistically augments the cGAS-STING activation in irradiated tumors, thereby enhancing RT-triggered local and system effects when combined with an immune checkpoint inhibitor. Therefore, the synchronous radiosensitization with sustained STING activation is demonstrated as a potent immunostimulation strategy to optimize cancer radio-immuotherapy.


Assuntos
Háfnio , Compostos de Manganês , Neoplasias , Humanos , Compostos de Manganês/farmacologia , Óxidos/farmacologia , Óxidos/uso terapêutico , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Nucleotidiltransferases
4.
Front Immunol ; 14: 1216585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37575244

RESUMO

Introduction: The heterogeneity of tumor immune microenvironments is a major factor in poor prognosis among hepatocellular carcinoma (HCC) patients. Neutrophils have been identified as playing a critical role in the immune microenvironment of HCC based on recent single-cell studies. However, there is still a need to stratify HCC patients based on neutrophil heterogeneity. Therefore, developing an approach that efficiently describes "neutrophil characteristics" in HCC patients is crucial to guide clinical decision-making. Methods: We stratified two cohorts of HCC patients into molecular subtypes associated with neutrophils using bulk-sequencing and single-cell sequencing data. Additionally, we constructed a new risk model by integrating machine learning analysis from 101 prediction models. We compared the biological and molecular features among patient subgroups to assess the model's effectiveness. Furthermore, an essential gene identified in this study was validated through molecular biology experiments. Results: We stratified patients with HCC into subtypes that exhibited significant differences in prognosis, clinical pathological characteristics, inflammation-related pathways, levels of immune infiltration, and expression levels of immune genes. Furthermore, A risk model called the "neutrophil-derived signature" (NDS) was constructed using machine learning, consisting of 10 essential genes. The NDS's RiskScore demonstrated superior accuracy to clinical variables and correlated with higher malignancy degrees. RiskScore was an independent prognostic factor for overall survival and showed predictive value for HCC patient prognosis. Additionally, we observed associations between RiskScore and the efficacy of immune therapy and chemotherapy drugs. Discussion: Our study highlights the critical role of neutrophils in the tumor microenvironment of HCC. The developed NDS is a powerful tool for assessing the risk and clinical treatment of HCC. Furthermore, we identified and analyzed the feasibility of the critical gene RTN3 in NDS as a molecular marker for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neutrófilos , Neoplasias Hepáticas/genética , Tomada de Decisão Clínica , Aprendizado de Máquina , Microambiente Tumoral/genética
5.
ACS Nano ; 17(14): 13195-13210, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37256771

RESUMO

Radiotherapy (RT) is one of the important clinical treatments for local control of triple-negative breast cancer (TNBC), but radioresistance still exists. Ferroptosis has been recognized as a natural barrier for cancer progression and represents a significant role of RT-mediated anticancer effects, while the simultaneous activation of ferroptosis defensive system during RT limits the synergistic effect between RT and ferroptosis. Herein, we engineered a tumor microenvironment (TME) degradable nanohybrid with a dual radiosensitization manner to combine ferroptosis induction and high-Z effect based on metal-organic frameworks for ferroptosis-augmented RT of TNBC. The encapsulated l-buthionine-sulfoximine (BSO) could inhibit glutathione (GSH) biosynthesis for glutathione peroxidase 4 (GPX4) inactivation to break down the ferroptosis defensive system, and the delivered ferrous ions could act as a powerful ferroptosis executor via triggering the Fenton reaction; the combination of them induces potent ferroptosis, which could synergize with the surface decorated Gold (Au) NPs-mediated radiosensitization to improve RT efficacy. In vivo antitumor results revealed that the nanohybrid could significantly improve the therapeutic efficacy and antimetastasis efficiency based on the combinational mechanism between ferroptosis and RT. This work thus demonstrated that combining RT with efficient ferroptosis induction through nanotechnology was a feasible and promising strategy for TNBC treatment.


Assuntos
Ferroptose , Neoplasias de Mama Triplo Negativas , Humanos , Anestésicos Locais , Butionina Sulfoximina , Fibrinolíticos , Glutationa , Linhagem Celular Tumoral , Microambiente Tumoral
6.
J Immunol ; 209(6): 1059-1070, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36002233

RESUMO

The BCR-associated protein 31 (BAP31), a transmembrane protein in the endoplasmic reticulum, participates in the regulation of immune cells, such as microglia and T cells, and has potential functions in macrophages that remain to be unexplored. In this study, we designed and bred macrophage-specific BAP31 knockdown mice to detect the polarization and functions of macrophages. The results revealed that M2 macrophage-associated genes were suppressed in mouse bone marrow-derived macrophages of Lyz2 Cre-BAP31flox/flox mice. Multiple macrophage-associated transcription factors were demonstrated to be able to be regulated by BAP31. Among these factors, C/EBPß was the most significantly decreased and was regulated by early growth response 2. BAP31 could also affect C/EBPß via modulating IL-4Rα ubiquitination and proteasome degradation in IL-4-stimulated macrophages. Furthermore, we found that BAP31 affects macrophages functions, including angiogenesis and skin fibrosis, during the wound healing process through IL-4Rα, as confirmed by infection with adeno-associated virus-short hairpin (sh)-IL-4Rα in Lyz2 Cre-BAP31flox/flox mice. Our findings indicate a novel mechanism of BAP31 in regulating macrophages and provide potential solutions for the prevention and treatment of chronic wounds.


Assuntos
Macrófagos , Proteínas de Membrana , Complexo de Endopeptidases do Proteassoma , Cicatrização , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Macrófagos/citologia , Proteínas de Membrana/metabolismo , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores de Superfície Celular/metabolismo
7.
Acta Biomater ; 141: 364-373, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35063709

RESUMO

Tumor vasculature-targeting therapy either using angiogenesis inhibitors or vascular disrupting agents offers an important new avenue for cancer therapy. In this work, a tumor-specific catalytic nanomedicine for enhanced tumor ablation accompanied with tumor vasculature disruption and angiogenesis inhibition was developed through a cascade reaction with enzyme glucose oxidase (GOD) modified on Fe-based metal organic framework (Fe-MOF) coupled with anti-VEGFR2.The GOD enzyme could catalyze the intratumoral glucose decomposition to trigger tumor starvation and yet provide abundant hydrogen peroxide as the substrate for Fenton-like reaction catalyzed by Fe-MOF to produce sufficient highly toxic hydroxyl radicals for enhanced chemodynamic therapy and instantly attacked tumor vascular endothelial cells to destroy the existing vasculature, while the anti-VEGFR2 antibody guided the nanohybrids to target blood vessels and block the VEGF-VEGFR2 connection to prevent angiogenesis. Both in vitro and in vivo results demonstrated the smart nanohybrids could cause the tumor cell apoptosis and vasculature disruption, and exhibited enhanced tumor regression in A549 xenograft tumor-bearing mice model. This study suggested that synergistic targeting tumor growth and its vasculature network would be more promising for curing solid tumors. STATEMENT OF SIGNIFICANCE: Cooperative destruction of tumor cells and tumor vasculature offers a potential avenue for cancer therapy. Under this premise, a tumor-specific catalytic nanomedicine for enhanced tumor ablation accompanied with tumor vasculature disruption and new angiogenesis inhibition was developed through a cascade reaction with glucose oxidase modified on the surface of iron-based metal organic framework coupled with VEGFR2 antibody. The resulting data demonstrated that a therapeutic regimen targeting tumor growth as well as its vasculature with both existing vasculature disruption and neovasculature inhibition would be more potential for complete eradication of tumors.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Animais , Catálise , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Glucose Oxidase/química , Humanos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
8.
Sheng Li Xue Bao ; 73(6): 893-900, 2021 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-34961863

RESUMO

The purpose of the present study was to investigate the effect and potential mechanism of knockdown of sphingosine kinase-1 (SPHK1) on the proliferation, cell cycle and apoptosis of non-small cell lung cancer (NSCLC) cells. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect SPHK1 mRNA expression in human healthy lung fibroblasts (MRC-5 cells) and four NSCLC cell lines. Then, A549 and H1299 cells were transfected with SPHK1-shRNA and corresponding negative control. CCK-8, Annexin V-FITC/PI dual staining and cell cycle assay were performed to evaluate cell proliferation, apoptosis and cell cycle distribution, respectively. JC-1 mitochondrial membrane potential measurement kit was adopted to measure mitochondrial membrane potential. Western blot was used to detect the protein expression levels of cell cycle and mitochondrial apoptotic pathway-related proteins, as well as MEK/ERK signaling pathway. The results showed that the mRNA expression of SPHK1 in NSCLC cells was higher than that in MRC-5 cells. SPHK1-shRNA significantly inhibited the proliferation of A549 and H1299 cells, blocked the cell cycle in G0/G1 phase, and promoted cell apoptosis through the mitochondrial pathway. Compared with the control group, the expression of p-MEK and p-ERK proteins in the SPHK1-shRNA group was significantly down-regulated. Moreover, MEK/ERK inhibitor could dramatically suppress cell proliferation and promote cell apoptosis. These results suggest that SPHK1 knockdown can inhibit the proliferation of NSCLC cells and might promote mitochondrial apoptotic pathway by inhibiting MEK/ERK signaling pathway.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Apoptose , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/genética
9.
ACS Appl Mater Interfaces ; 13(45): 53504-53518, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34704726

RESUMO

With the recent success of immune checkpoint blockade (ICB) in cancer immunotherapy, there has been renewed interest in evaluating the combination of ICB inhibitors with radiotherapy (RT) in clinical trials in view of the localized RT-initiated vaccination effect, which can be augmented further by systemic immune-stimulating agents. Unfortunately, traditional RT/ICB accompanies severe toxicity from high-dose ionizing irradiation and low response rate from RT-aggravated immunosuppression, among which M2-type tumor-associated macrophages (TAMs) play an important role. Herein, CpG-decorated gold (Au) nanoparticles (CpG@Au NPs) were fabricated to improve the RT/ICB efficacy by immune modulation under low-dose X-ray exposure, where Au NPs served as radioenhancers to minimize the radiotoxicity, and yet acted as nanocarriers to deliver CpG, a toll-like receptor 9 agonist, to re-educate immunosuppressive M2 TAMs to immunostimulatory M1 counterparts, thus arousing innate immunity and meanwhile priming T cell activation. When combined with an anti-programmed death 1 antibody, irradiated CpG@Au led to consistent abscopal responses that efficiently suppressed distant tumors in a bilateral GL261 tumor-bearing model. This work thus demonstrates that CpG@Au-mediated macrophage reeducation could efficiently modulate the tumor-immune microenvironment for synergistic RT/ICB.


Assuntos
Glioma/terapia , Ouro/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia , Nanocompostos/química , Oligodesoxirribonucleotídeos/farmacologia , Macrófagos Associados a Tumor/efeitos dos fármacos , Animais , Ouro/química , Inibidores de Checkpoint Imunológico/química , Camundongos , Oligodesoxirribonucleotídeos/química , Células Tumorais Cultivadas , Microambiente Tumoral/efeitos dos fármacos
10.
Mol Med Rep ; 24(5)2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34515321

RESUMO

Bladder cancer has high morbidity and mortality rates among the male genitourinary system tumor types. MicroRNA­218 (miR­218) is associated with the development of a variety of cancer types, including bladder cancer. Rab6c is a member of the Rab family and is involved in drug resistance in MCF7 cells. The aim of the present study was to clarify the relationship between Rab6c and miR­218 in bladder cancer cell lines. In this study, the expression levels of miR­218 and Rab6c were evaluated via reverse transcription­quantitative PCR and western blotting, respectively. The association between Rab6c and miR­218 was recognized via TargetScan analysis and dual luciferase reporter gene detection. Cell proliferation was analyzed using Cell Counting Kit­8 and colony formation assays, and the invasive ability was measured via Transwell assays. Rab6c was highly expressed in bladder cancer, while miR­218 had abnormally low expression in bladder cancer. In addition, there was a mutual regulation between Rab6c and miR­218 in bladder cancer. It was found that overexpression of Rab6c significantly enhanced the proliferation, colony formation and invasion of T24 and EJ cells. Furthermore, miR­218 overexpression blocked the promoting effects of Rab6c on the malignant behavior of bladder cancer cells. Thus, Rab6c promotes the proliferation and invasion of bladder cancer cells, while miR­218 has the opposite effect, which may provide a novel insight for the treatment of bladder cancer.


Assuntos
MicroRNAs/genética , Neoplasias da Bexiga Urinária/genética , Proteínas rab de Ligação ao GTP/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , China , Progressão da Doença , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Neoplasias da Bexiga Urinária/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
11.
J Mater Chem B ; 9(2): 208-227, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33215626

RESUMO

Radiotherapy (RT) plays a central role in curing malignant tumors. However, the treatment outcome is often impeded by low radiation absorption coefficients and radiation resistance of tumors along with normal tissue radio-toxicity. With the development of nanotechnology, nanomaterials in combination with RT offer the possibility to improve the therapeutic efficacy yet reduce side-effects. Metal-ligand coordination nanomaterials, including nanoscale metal-organic frameworks (NMOFs) and nanoscale coordination polymers (NCPs), formed by coordination interactions between inorganic metal ions/clusters with organic bridging ligands, have shown great potential in the field of radiation oncology in recent years in view of their unique advantages including the porous structure, high surface area, periodic frameworks, and diverse selections of both metal ions/clusters and organic ligands. In this review, we summarize the recent advances in NMOF/NCP-mediated synergistic RT in combination with hypoxia relief, chemotherapy, photodynamic therapy, photothermal therapy, chemodynamic therapy or immunotherapy, which emerged in the last 3 years, and describe cooperative enhancement interactions among these synergistic combinations. Moreover, the potential challenges and future prospects of this rapidly growing direction were also addressed.


Assuntos
Imunoterapia/métodos , Estruturas Metalorgânicas/química , Nanoestruturas/química , Radioterapia/métodos , Humanos , Ligantes
12.
Front Oncol ; 10: 589112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363019

RESUMO

Magnesium, the second most predominant intracellular cation, plays a crucial role in many physiological functions; magnesium-based biomaterials have been widely used in clinical application. In a variety of cancer types, the high intracellular concentration of magnesium contributes to cancer initiation and progression. Therefore, we initiated this study to investigate the likelihood of confounding magnesium with cancer therapy. In this study, the anti-tumor activity of magnesium and underlying mechanisms were assessed in bladder cancer both in vitro and in vivo. The results indicated that the proliferation of bladder cancer cells was inhibited by treatment with a high concentration of MgCl2 or MgSO4. The apoptosis, G0/G1 cell cycle arrest, autophagy, and ER stress were promoted following treatment with MgCl2. However, the migratory ability of MgCl2 treated cells was similar to that of control cells, as revealed by the trans-well assay. Besides, no significant difference was observed in the proportion of CD44 or CD133 positive cells between the control and MgCl2 treated cells. Thus, to improve the therapeutic effect of magnesium, VPA was used to treat cancer cells in combination with MgCl2. As expected, combination treatment with MgCl2 and VPA could markedly reduce proliferation, migration, and in vivo tumorigenicity of UC3 cells. Moreover, the Wnt signaling was down-regulated, and ERK signaling was activated in the cells treated with combination treatment. In conclusion, the accurate utilization of MgCl2 in targeting autophagy might be beneficial in cancer therapy. Although further studies are warranted, the combination treatment of MgCl2 with VPA is an effective strategy to improve the outcome of chemotherapy.

13.
Biotechnol J ; 15(8): e1900430, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170989

RESUMO

Cyclin D1 is a key regulatory factor of the G1 to S transition during cell cycle progression. Aberrant cyclin D gene amplification and abnormal protein expression have been linked to hepatocellular carcinoma (HCC) tumorigenesis. Intrabodies, effective anticancer therapies that specifically inhibit target protein function within all intracellular compartments, may block cyclin D1 function. Here, a single-chain variable fragment (scFv) antibody against cyclin D1 (ADκ) selected from a human semi-synthetic phage display scFv library is expressed in Escherichia coli as soluble ADκ. Purified ADκ specifically binds to recombinant and endogenous cyclin D1 with high affinity. To enable blocking of intracellular cyclin D1 activity, an endoplasmic reticulum (ER) retention signal sequence is added to the ADκ sequence to encode anti-cyclin D1 intrabody ER-ADκ. Transfection of HepG2 cells with expression vector encoding ER-ADκ elicited intracellular ER-ADκ expression leading to cyclin D1 binding, significant G1 phase arrest, and apoptosis that are mechanistically tied to decreased intracellular phosphorylated retinoblastoma protein (Rb) levels. Meanwhile, ER-ADκ dramatically inhibited subcutaneous human HCC xenografts growth in nude mice in vivo after injection of tumors with expression vector encoding ER-ADκ. These results demonstrate the potential of intrabody-based cyclin D1 targeting therapy as a promising treatment for HCC.


Assuntos
Carcinoma Hepatocelular , Divisão Celular , Proliferação de Células , Ciclina D1 , Anticorpos de Cadeia Única , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Ciclo Celular , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Camundongos Nus , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/farmacologia , Anticorpos de Cadeia Única/uso terapêutico
14.
ACS Appl Mater Interfaces ; 12(10): 11979-11989, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32091868

RESUMO

A high-performance formaldehyde sensor based on nickel (Ni)-doped indium trioxide (In2O3)/tungsten disulfide (WS2) nanocomposite was demonstrated. An epoxy substrate served as matrix of the Ni-In2O3/WS2 nanocomposite sensor. The material properties of self-assembled Ni-In2O3/WS2 nanoheterostructure were fully characterized and confirmed. The formaldehyde-sensing properties of the Ni-In2O3/WS2 composite were tested at 25 °C. Compared to the In2O3, WS2, and their composite, the Ni-In2O3/WS2 sensor demonstrated significant improvement on the formaldehyde-sensing performance, including a low detection limit of 15 ppb, good selectivity, repeatability, fast detection rate, and a fair logarithmic function toward formaldehyde concentration. The dramatically enhanced sensing performance of Ni-In2O3/WS2 film sensor can be attributed to the Ni ion doping and synergistic interfacial incorporation of In2O3/WS2 heterojunction. The sensitive mechanism of the Ni-In2O3/WS2 film sensor toward formaldehyde is explored through density functional theory (DFT) simulation. This work verified that the synthesis of Ni-doped In2O3/WS2 nanofilm provides a new avenue to develop promising hybrids for formaldehyde sensing.

15.
Cancer Cell Int ; 20: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31920463

RESUMO

BACKGROUND: Aurora kinase A (AURKA) has been implicated in the regulation of cell cycle progression, mitosis and a key number of oncogenic signaling pathways in various malignancies including neuroblastoma. Small molecule inhibitors of AURKA have shown potential, but still not as good as expected effects in clinical trials. Little is known about this underlying mechanism. Here, we evaluated the inhibitory effects of AURKA inhibitor MLN8237 on neuroblastoma cells to understand the potential mechanisms responsible for tumor therapy. METHODS: MLN8237 treatment on neuroblastoma cell line IMR32 was done and in vivo inhibitory effects were investigated using tumor xenograft model. Cellular senescence was evaluated by senescence-associated ß-gal Staining assay. Flow cytometry was used to tested cell cycle arrest and cell apoptosis. Senescence-associated signal pathways were detected by western blot. CD133 microbeads and microsphere formation were used to separate and enrich CD133+ cells. AURKA small interfering RNA transfection was carried to downregulate AURKA level. Finally, the combination of MLN8237 treatment with AURKA small interfering RNA transfection were adopted to evaluate the inhibitory effect on neuroblastoma cells. RESULTS: We demonstrate that MLN8237, an inhibitor of AURKA, induces the neuroblastoma cell line IMR32 into cellular senescence and G2/M cell phase arrest. Inactivation of AURKA results in MYCN destabilization and inhibits cell growth in vitro and in a mouse model. Although MLN8237 inhibits AURKA kinase activity, it has almost no inhibitory effect on the AURKA protein level. By contrast, MLN8237 treatment leads to abnormal high expression of AURKA in vitro and in vivo. Knockdown of AURKA reduces cell survival. The combination of MLN8237 with AURKA small interfering RNA results in more profound inhibitory effects on neuroblastoma cell growth. Moreover, MLN8237 treatment followed by AURKA siRNA forces senescent cells into apoptosis via suppression of the Akt/Stat3 pathway. CONCLUSIONS: The effect of AURKA-targeted inhibition of tumor growth plays roles in both the inactivation of AURKA activity and the decrease in the AURKA protein expression level.

16.
ACS Appl Mater Interfaces ; 11(34): 31245-31256, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31365825

RESUMO

This paper reports an original fabrication of a benzene gas sensor based on tungsten disulfide nanoflowers (WS2 NFs)/zinc oxide hollow spheres (ZnO HMDs) hierarchical nanoheterostructure. The ZnO/WS2 hierarchical composite was characterized for the inspection of its nanostructure, elementary composition, and surface morphology. The benzene-sensing properties of the ZnO/WS2 nanofilm sensor were exactly investigated. The results illustrate that the ZnO/WS2 sensor exhibits a remarkable sensing performance toward benzene gas, including good sensitivity, rapid detection, outstanding repeatability, and stability. This is attributed to the fact that the ZnO/WS2 nanoheterostructure can dramatically enhance the benzene sensing performance. Furthermore, density functional theory was employed to construct the benzene gas adsorption model for the ZnO/WS2 heterostructure, from which the determined parameters in geometry, energy, and charge provided a powerful support for the mechanism explanation. This work suggests that the ZnO/WS2 nanoheterostructure is competent to detect trace benzene gas at room temperature.

17.
J Colloid Interface Sci ; 529: 556-567, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29958114

RESUMO

In this paper, a high-performance ethanol sensor based on iron (Fe)-doped titanium dioxide (TiO2)/molybdenum disulfide (MoS2) nanocomposite was demonstrated. Flower-like MoS2 and Fe-TiO2 quantum dots (QDs) were synthesized by a facile hydrothermal route, and the Fe-TiO2/MoS2 composite was prepared via layer-by-layer (LbL) self-assembly technique. The Fe-TiO2/MoS2 film sensor was fabricated on a flame resistant (FR-4) epoxy substrate with interdigital electrodes. The microstructure, elementary composition, and morphology of the as-prepared samples were fully characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS). The gas sensing properties of the Fe-TiO2/MoS2 film sensor were determined at room temperature upon exposure to different concentration of ethanol gas. The experimental results illustrated that high response, short response/recovery time, stable repeatability, excellent selectivity long-term stability, and a detection limit of low ppb level was achieved by the Fe-TiO2/MoS2 sensor. The underlying sensing mechanism of the Fe-TiO2/MoS2 sensor toward ethanol is explored through systematically experimental investigation combining with first-principle density-functional theory (DFT) simulations. The enhanced ethanol sensing properties were ascribed to the Fe3+ ion doping, and p-n heterojunctions created at interfaces of n-type Fe-TiO2 and p-type MoS2.

18.
J Colloid Interface Sci ; 528: 184-191, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29852348

RESUMO

An ethanol gas sensor based on lead sulfide (PbS) quantum dots (QDs)-decorated zinc oxide (ZnO) nanorods were demonstrated in this article. The PbS QDs/ZnO film was fabricated via tuning PbS QDs deposition onto the hydrothermally synthesized ZnO nanorods via successive ionic-layer adsorption and reaction (SILAR) method. The PbS QDs/ZnO nanorods nanocomposite was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscope. The ethanol gas sensing properties of the PbS QDs/ZnO nanorods-based sensor with different SILAR layers of PbS QDs was investigated at room temperature. The experimental results showed that high response, short response and recovery time, and good repeatability were yielded for the PbS QDs/ZnO nanorods-based sensor, and the optimal SILAR cycle of PbS QDs was discovered to achieve the best ethanol gas sensing performance. The possible sensing mechanism of the PbS QDs/ZnO nanorods-based sensor was attributed to the porous flower-like morphologies, heterojunction nanostructure and high ratio of accessible sites for gas diffusion.

19.
Nat Prod Res ; 30(21): 2429-33, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27279288

RESUMO

A new phenolic glycoside derivative, saproglucoside (1), along with five known phenolic glycoside derivatives (2-6) were isolated from the stems of Saprosma merrillii. The structure of the new compound 1 was determined by 1D and 2D NMR as well as by HRESIMS and hydrolysis. The inhibitory activities of all compounds against seven pathogenic bacteria and two cancer cell lines were evaluated.


Assuntos
Glucosídeos/isolamento & purificação , Fenóis/isolamento & purificação , Rubiaceae/química , Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Glucosídeos/química , Glucosídeos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Fenóis/química , Fenóis/farmacologia
20.
ACS Appl Mater Interfaces ; 7(11): 6331-9, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25741576

RESUMO

Currently, combining biomaterial scaffolds with living stem cells for tissue regeneration is a main approach for tissue engineering. Mesenchymal stem cells (MSCs) are promising candidates for musculoskeletal tissue repair through differentiating into specific tissues, such as bone, muscle, and cartilage. Thus, successfully directing the fate of MSCs through factors and inducers would improve regeneration efficiency. Here, we report the fabrication of graphene oxide (GO)-doped poly(lactic-co-glycolic acid) (PLGA) nanofiber scaffolds via electrospinning technique for the enhancement of osteogenic differentiation of MSCs. GO-PLGA nanofibrous mats with three-dimensional porous structure and smooth surface can be readily produced via an electrospinning technique. GO plays two roles in the nanofibrous mats: first, it enhances the hydrophilic performance, and protein- and inducer-adsorption ability of the nanofibers. Second, the incorporated GO accelerates the human MSCs (hMSCs) adhesion and proliferation versus pure PLGA nanofiber and induces the osteogenic differentiation. The incorporating GO scaffold materials may find applications in tissue engineering and other fields.


Assuntos
Grafite/química , Ácido Láctico/química , Células-Tronco Mesenquimais/citologia , Nanofibras/química , Osteoblastos/citologia , Ácido Poliglicólico/química , Alicerces Teciduais , Materiais Biocompatíveis/síntese química , Diferenciação Celular/fisiologia , Proliferação de Células , Células Cultivadas , Galvanoplastia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/fisiologia , Nanofibras/ultraestrutura , Osteoblastos/fisiologia , Osteogênese/fisiologia , Óxidos/química , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Gravidez , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
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