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1.
BMC Oral Health ; 24(1): 112, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243239

RESUMO

BACKGROUND: The outer membrane vesicles (OMVs) derived from Porphyromonas gingivalis (P. gingivalis) have long been acknowledged for their crucial role in the initiation of periodontitis. However, the implications of P. gingivalis OMVs in the context of cardiovascular disease (CVD) remain incompletely understood. This study aimed to clarify both the impact and the underlying mechanisms through which P. gingivalis OMVs contribute to the propagation of distal cardiovascular inflammation and trauma. METHODS: In this study, various concentrations (0, 1.25, 2.5, and 4.5 µg/µL) of P. gingivalis OMVs were microinjected into the common cardinal vein of zebrafish larvae at 48 h post-fertilization (hpf) to assess changes in cardiovascular injury and inflammatory response. Zebrafish larvae from both the PBS and the 2.5 µg/µL injection cohorts were harvested at 30 h post-injection (hpi) for transcriptional analysis. Real-time quantitative PCR (RT-qPCR) was employed to evaluate relative gene expression. RESULTS: These findings demonstrated that P. gingivalis OMVs induced pericardial enlargement in zebrafish larvae, caused vascular damage, increased neutrophil counts, and activated inflammatory pathways. Transcriptomic analysis further revealed the involvement of the immune response and the extracellular matrix (ECM)-receptor interaction signaling pathway in this process. CONCLUSION: This study illuminated potential mechanisms through which P. gingivalis OMVs contribute to CVD. It accentuated their involvement in distal cardiovascular inflammation and emphasizes the need for further research to comprehensively grasp the connection between periodontitis and CVD.


Assuntos
Doenças Cardiovasculares , Estruturas Embrionárias , Periodontite , Sistema Porta/embriologia , Humanos , Animais , Porphyromonas gingivalis/genética , Peixe-Zebra , Inflamação
2.
J Phys Chem C Nanomater Interfaces ; 127(24): 11736-11747, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37377502

RESUMO

Polymer nanocomposites (NCs) offer outstanding potential for dielectric applications including insulation materials. The large interfacial area introduced by the nanoscale fillers plays a major role in improving the dielectric properties of NCs. Therefore, an effort to tailor the properties of these interfaces can lead to substantial improvement of the material's macroscopic dielectric response. Grafting electrically active functional groups to the surface of nanoparticles (NPs) in a controlled manner can yield reproducible alterations in charge trapping and transport as well as space charge phenomena in nanodielectrics. In the present study, fumed silica NPs are surface modified with polyurea from phenyl diisocyanate (PDIC) and ethylenediamine (ED) via molecular layer deposition (MLD) in a fluidized bed. The modified NPs are then incorporated into a polymer blend based on polypropylene (PP)/ethylene-octene-copolymer (EOC), and their morphological and dielectric properties are investigated. We demonstrate the alterations in the electronic structure of silica upon depositing urea units using density functional theory (DFT) calculations. Subsequently, the effect of urea functionalization on the dielectric properties of NCs is studied using thermally stimulated depolarization current (TSDC) and broadband dielectric spectroscopy (BDS) methods. The DFT calculations reveal the contribution of both shallow and deep traps upon deposition of urea units onto the NPs. It could be concluded that the deposition of polyurea on NPs results in a bi-modal distribution of trap depths that are related to each monomer in the urea units and can lead to a reduction of space charge formation at filler-polymer interfaces. MLD offers a promising tool for tailoring the interfacial interactions in dielectric NCs.

3.
Adv Mater ; 35(17): e2208546, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36745572

RESUMO

Immunotherapy shows immense promise for improving cancer treatment. Combining immunotherapy with radiotherapy provides a conspicuous advantage due to its enhanced abscopal effect. However, established immune tolerance mechanisms in the tumor microenvironment can hamper the generation of a sufficient abscopal effect. Herein, a type of DNA nanocluster (DNAnc) that is self-assembled by a CpG-ODNs-loaded Y-shaped double-stranded DNA vector based on the unique complementary base-pairing rules is designed. The unique structure of DNAnc makes it load more than ≈8125.5 ± 822.5 copies of CpG ODNs within one single nanostructure, which effectively increases resistance to nuclease degradation and elevates the efficiency of repolarizing macrophages to an M1-like phenotype. Mechanistic studies reveal that more DNAncs are endocytosed by macrophages in the cancer tissue and repolarized macrophages to elicit a robust abscopal effect with the accumulation of macrophages induced by radiotherapy, generating potent, long-term, and durable antitumor immunity for the inhibition of tumor metastasis and the prevention of tumor recurrence, which provides a novel strategy to boost cancer immunotherapy.


Assuntos
Neoplasias , Radioimunoterapia , Radioimunoterapia/métodos , DNA/química , DNA/genética , Nanoestruturas , Humanos , Animais , Camundongos , Linhagem Celular , Fenômenos Químicos , Memória Imunológica , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia
4.
Inflamm Regen ; 43(1): 6, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36703231

RESUMO

The integrity of the corneal epithelium is essential for the maintenance of the physiological function of the cornea. Studies have found that inflammation greatly delays corneal wound healing. NF-κB c-Rel is preferentially expressed by immune cells and promotes the expression of inflammatory cytokines. In the current study, we sought to investigate whether c-Rel could be used as a potential therapeutic target for treating a corneal injury. Our studies reveal that expressions of c-Rel and its inflammatory targets are significantly increased in the cornea of mice with corneal injury. In addition, we find that c-Rel-deficient mice exhibit accelerated corneal wound healing and reduced expression of inflammatory cytokines. Further studies show that topical treatment on the corneal surface using nano-polymers or exosomes loaded with c-Rel-specific siRNA (siRel) can effectively accelerate regular and diabetic corneal wound healing. More importantly, we find that exosomes, as carriers of siRel, showed better efficacy than nano-polymers in treating corneal injury. We further demonstrate that exosomes secreted by mesenchymal stem cells can efficiently transfer siRNA into macrophages and dendritic cells but not T cells. Taken together, these results indicate that blocking c-Rel may represent an attracting strategy for the treatment of both regular and diabetic corneal injury.

5.
Nat Commun ; 13(1): 3545, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729232

RESUMO

Pancreatic ß cell dysfunction contributes to the pathogenesis of type 2 diabetes. MiR-21 has been shown to be induced in the islets of glucose intolerant patients and type 2 diabetic mice. However, the role of miR-21 in the regulation of pancreatic ß cell function remains largely elusive. In the current study, we identify the pathway by which miR-21 regulates glucose-stimulated insulin secretion utilizing mice lacking miR-21 in their ß cells (miR-21ßKO). We find that miR-21ßKO mice develop glucose intolerance due to impaired glucose-stimulated insulin secretion. Mechanistic studies reveal that miR-21 enhances glucose uptake and subsequently promotes insulin secretion by up-regulating Glut2 expression in a miR-21-Pdcd4-AP-1 dependent pathway. Over-expression of Glut2 in knockout islets results in rescue of the impaired glucose-stimulated insulin secretion. Furthermore, we demonstrate that delivery of miR-21 into the pancreas of type 2 diabetic db/db male mice is able to promote Glut2 expression and reduce blood glucose level. Taking together, our results reveal that miR-21 in islet ß cell promotes insulin secretion and support a role for miR-21 in the regulation of pancreatic ß cell function in type 2 diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Glucose , Células Secretoras de Insulina , MicroRNAs , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Glucose/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
7.
Small Methods ; 5(11): e2100770, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34927965

RESUMO

Immune and targeted therapy are becoming the first-line treatment for renal cell carcinoma (RCC). However, therapeutic outcomes are limited due to the low efficiency and side effect. Here, it is found that helicenes are able to exhibit an anticancer capability through changing the molecular structure from planar to nonplanar. Furthermore, the cytotoxicity in vitro and cancer inhibition ability of nonplanar helicenes increase with its aromatic rings' number. It is further demonstrated that benzo[4]helicenium shows the specific killing efficiency against the RCC cancer as compared to normal kidney cells. This is majorly originated from a more selective damage of benzo[4]helicenium for mitochondria and DNA in RCC cancer cells, not the normal kidney. The selective killing ability of benzo[4]helicenium makes it have potential to be used as a targeted drug for the precise treatment of RCC.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Perfilação da Expressão Gênica/métodos , Neoplasias Renais/tratamento farmacológico , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Compostos Policíclicos/síntese química , Animais , Carcinoma de Células Renais/genética , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Humanos , Neoplasias Renais/genética , Masculino , Camundongos , Camundongos Nus , Estrutura Molecular , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , RNA-Seq , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Front Immunol ; 12: 766757, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858422

RESUMO

Regulatory T cells (Tregs) are considered important for controlling the onset and development of autoimmune disease. Although studies have shown that miR-21 is expressed at higher levels in Treg cells, it remains largely elusive whether miR-21 regulates the immune-suppressive function of Tregs. In the current study, we generated mice lacking miR-21 specifically in their Tregs and investigated the role of miR-21 in regulating Treg function both in vitro and in vivo. Our study revealed that Tregs lacking miR-21 exhibit normal phenotype and unaltered function in suppressing T cell proliferation and dendritic cell activation in vitro. However, compared with miR-21-sufficient Tregs, they produce significant more IL-17 and IL-10 when under pathogenic Th17-priming condition. Adenoviral delivery of miR-21 into Treg cells is able to reduce the expression of both IL-17 and IL-10. Mechanistic study revealed that miR-21 down-regulates IL-10 expression through direct targeting of IL-10, and suppresses reprogramming of Tregs into IL-17-secreting cells through down-regulating Stat3 activity. However, we detected no significant or marginal difference in the development of various autoimmune diseases between wild type mice and mice with Treg-specific deletion of miR-21. In conclusion, our study demonstrated that miR-21 in Tregs regulates diametrically opposed biological Treg functions and is largely dispensable for the development of autoimmune disease.


Assuntos
Doenças Autoimunes/imunologia , Regulação da Expressão Gênica/imunologia , Ativação Linfocitária/imunologia , MicroRNAs/imunologia , Linfócitos T Reguladores/imunologia , Animais , Apoptose/genética , Apoptose/imunologia , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Proliferação de Células/genética , Interferon gama/genética , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-17/metabolismo , Ativação Linfocitária/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Linfócitos T Reguladores/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
9.
Biomolecules ; 11(9)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34572513

RESUMO

As a vertebrate model, zebrafish (Danio rerio) plays a vital role in the field of life sciences. Recently, gene-editing technology has become increasingly innovative, significantly promoting scientific research on zebrafish. However, the implementation of these methods in a reasonable and accurate manner to achieve efficient gene-editing remains challenging. In this review, we systematically summarize the development and latest progress in zebrafish gene-editing technology. Specifically, we outline trends in double-strand break-free genome modification and the prospective applications of fixed-point orientation transformation of any base at any location through a multi-method approach.


Assuntos
Edição de Genes , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Quebras de DNA de Cadeia Dupla , Marcação de Genes , Moldes Genéticos
10.
Am J Transplant ; 21(12): 3858-3870, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34254428

RESUMO

The relevance of Tregs in the induction of tolerance against corneal allografts has been well established. Although it is well known that the conversion of Tregs into effector-like cells contributes to the loss of corneal immune privilege, the underlying mechanism is still not fully understood. Using heterologous penetrating keratoplasty model, we found that Tregs from corneal allograft rejected mice (inflam-Tregs) exhibit impaired function and characteristics of effector T cells. Further study showed that the expression of NF-κB c-Rel, a key mediator of effector T cell function, was significantly increased in inflam-Tregs. Mechanistic study revealed that elevated NF-κB c-Rel level in inflam-Tregs impaired Treg function through the promotion of inflammatory cytokine production and glycolysis. More importantly, we demonstrated that targeting NF-κB c-Rel was able to improve the immune suppressive function of inflam-Tregs in vitro and enhance the potential of them to suppress corneal transplantation rejection. Therefore, our current study identified NF-κB c-Rel as a key mediator of the conversion of Tregs into effector-like cells when under inflammatory environment.


Assuntos
Transplante de Córnea , Linfócitos T Reguladores , Aloenxertos , Animais , Córnea , Rejeição de Enxerto/etiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NF-kappa B , Transplante Homólogo
11.
Langmuir ; 37(15): 4481-4492, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33823592

RESUMO

Functionalized nanoparticles have various applications, for which grafting of a chemical moiety onto the surface to induce/improve certain properties is needed. When incorporated in polymeric matrices, for instance, the modified nanoparticles can alter the interfacial characteristics leading to improvements ofthe macroscopic properties of the nanocomposites. The extent of these improvements is highly dependent on the thickness, morphology and conformity of the grafted layer. However, the common liquid-phase modification methods provide limited control over these factors. A novel gas-phase modification process was utilized, with 3-aminopropyltriethoxysilane (APTES) as precursor, to chemically deposit amino-terminated organic layers on fumed silica nanoparticles in a fluidized bed. A self-limiting surface saturation was achieved when the reaction was done at 200 °C. With this self-limiting feature, we were able to graft multiple layers of aminopropylsiloxane (APS) onto the silica nanoparticles using water as the coreactant. The feasibility of this process was analyzed using thermogravimetric analysis (TGA), diffuse reflectance IR Fourier transform spectroscopy (DRIFTS), X-ray photoelectron spectroscopy (XPS), and elemental analysis (EA). By altering the number of APTES/water cycles, it was possible to control the thickness and conformity of the deposited aminopropylsiloxane layer. This novel approach allows to engineer the surface of nanoparticles, by introducing versatile functionalized layers in a controlled manner.

12.
J Environ Sci (China) ; 103: 43-49, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33743917

RESUMO

The occurrence of the Maillard reaction and melanoidins formation during the hydrothermal treatment of food waste can reduce the yield of volatile fatty acids (VFA); however, few studies have investigated the adverse effects of the Maillard reaction. This study identified the impact of hydrothermal treatment parameters on hydrolysis and melanoidins formation and optimized the hydrothermal treatment conditions to enhance VFA production by minimizing the impact of the Maillard reaction. A response surface methodology was employed to optimize the hydrothermal treatment parameters and VFA production was evaluated. Results showed that temperature, reaction time, and pH were significant interacting factors with respect to hydrolysis and melanoidins formation while the C/N ratio and moisture content of food waste had little impact. The optimal conditions for hydrothermal treatment (temperature of 132 °C, reaction time of 27 min, and a pH of 5.6) enhanced VFA production by 22.1%. Under optimal hydrothermal treatment conditions, a higher initial C/N ratio further increased VFA production.


Assuntos
Alimentos , Eliminação de Resíduos , Reatores Biológicos , Ácidos Graxos Voláteis , Fermentação , Concentração de Íons de Hidrogênio , Reação de Maillard
13.
Adv Mater ; 33(7): e2003523, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33354783

RESUMO

The transfection efficiency of siRNA mediated by cationic polymers is limited due to the instability of polymers/siRNA complexes in the presence of serum. Poly(ethylene glycol) (PEG) is usually applied to modify cationic polymers, so as to reduce protein and cell adsorption and then to improve siRNA transfection efficiency. However, the polymers' modification with PEG mostly consumes the free amino of the polymers, which can, in turn, reduce the charge density and limit their siRNA transfection efficacy. Here, a new PEG modification strategy that need not consume the surface aminos of polymers is proposed. Catechol-PEG polymers are coated on the surface of phenylboronic acid (PBA)-modified Generation 5 (G5) poly(amidoamine) dendrimers (G5PBA) via reversible boronate esters to establish PEG-modified dendrimer/siRNA nanoassemblies for efficient siRNA delivery. The PEG/G5PBA/siRNA nanoassemblies have positive charge and show excellent gene silencing efficacy in the absence of serum in vitro. More importantly, the PEG/G5PBA/siRNA nanoassemblies also exhibit excellent serum resistance and gene silencing efficacy in serum-containing medium. Furthermore, the effective antiserum and gene silencing efficacy elicited by these nanoassemblies lead to excellent antitumor effects in vivo. This proposed strategy constitutes an important approach to reach an excellent gene silencing efficacy in the presence of serum.


Assuntos
Neoplasias da Mama/terapia , Tolerância a Medicamentos/genética , Inativação Gênica/efeitos dos fármacos , Nanoestruturas/química , RNA Interferente Pequeno/metabolismo , Soro/metabolismo , Animais , Ácidos Borônicos/química , Cátions/química , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Dendrímeros/química , Feminino , Genes erbB-1/genética , Terapia Genética , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Poliaminas/química , Polietilenoglicóis/química , Fatores de Tempo , Transfecção
14.
Nucleic Acids Res ; 48(10): e57, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32232370

RESUMO

Site-specific DNA double-strand breaks have been used to generate knock-in through the homology-dependent or -independent pathway. However, low efficiency and accompanying negative impacts such as undesirable indels or tumorigenic potential remain problematic. In this study, we present an enhanced reduced-risk genome editing strategy we named as NEO, which used either site-specific trans or cis double-nicking facilitated by four bacterial recombination factors (RecOFAR). In comparison to currently available approaches, NEO achieved higher knock-in (KI) germline transmission frequency (improving from zero to up to 10% efficiency with an average of 5-fold improvement for 8 loci) and 'cleaner' knock-in of long DNA fragments (up to 5.5 kb) into a variety of genome regions in zebrafish, mice and rats. Furthermore, NEO yielded up to 50% knock-in in monkey embryos and 20% relative integration efficiency in non-dividing primary human peripheral blood lymphocytes (hPBLCs). Remarkably, both on-target and off-target indels were effectively suppressed by NEO. NEO may also be used to introduce low-risk unrestricted point mutations effectively and precisely. Therefore, by balancing efficiency with safety and quality, the NEO method reported here shows substantial potential and improves the in vivo gene-editing strategies that have recently been developed.


Assuntos
Proteínas de Bactérias/metabolismo , Edição de Genes/métodos , Animais , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/metabolismo , Feminino , Técnicas de Introdução de Genes , Genômica , Recombinação Homóloga , Humanos , Mutação INDEL , Macaca fascicularis , Camundongos , Ratos Sprague-Dawley , Recombinases Rec A/metabolismo , Peixe-Zebra/genética
15.
J Immunol ; 204(8): 2053-2063, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32169850

RESUMO

Autoimmune diseases are a physiological state that immune responses are directed against and damage the body's own tissues. Numerous studies have demonstrated promising therapeutic effects in certain autoimmune diseases by targeting IL-23/IL-17 axis, mostly through using Abs against IL-23 or IL-17A. Pyrrole-imidazole polyamides are nuclease-resistant compounds that inhibit gene expression through binding to the minor groove of DNA. To develop a novel gene-silencing agent that targets IL-23/IL-17 axis, we designed polyamide that specifically binds to the transcription factor c-Rel-binding site located in the promoter of IL-23p19 subunit. Our study showed that this polyamide is capable of entering into nucleus with high efficiency in dendritic cells and macrophage. In addition, it prevented the binding of c-Rel to the promoter of IL-23p19 in vivo and specifically inhibited the expression of IL-23. More importantly, we demonstrated that this polyamide is therapeutically effective using both the imiquimod-induced psoriasis and experimental autoimmune uveitis mouse models. Taken together, these results indicate that pyrrole-imidazole polyamide targeting IL-23p19 could be a novel and feasible therapeutic strategy for patients with autoimmune diseases.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/genética , Inativação Gênica , Subunidade p19 da Interleucina-23/antagonistas & inibidores , Nylons/farmacologia , Animais , Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/imunologia , Feminino , Imidazóis/farmacologia , Imiquimode , Subunidade p19 da Interleucina-23/genética , Subunidade p19 da Interleucina-23/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Estrutura Molecular , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Psoríase/genética , Psoríase/imunologia , Pirróis/farmacologia , Uveíte/induzido quimicamente , Uveíte/tratamento farmacológico , Uveíte/genética , Uveíte/imunologia
17.
Polymers (Basel) ; 11(12)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795227

RESUMO

Novel nanocomposites for dielectric applications-based polypropylene/poly(ethylene-co-octene) (PP/POE) blends filled with nano silica are developed in the framework of the European 'GRIDABLE' project. A tailor-made low-pressure-plasma reactor was applied in this study for an organic surface modification of silica. Acetylene gas was used as the monomer for plasma polymerization in order to deposit a hydrocarbon layer onto the silica surface. The aim of this modification is to increase the compatibility between silica and the PP/POE blends matrix in order to improve the dispersion of the filler in the polymer matrix and to suppress the space charge accumulation by altering the charge trapping properties of these silica/PP/POE blends composites. The conditions for the deposition of the acetylene plasma-polymer onto the silica surface were optimized by analyzing the modification in terms of weight loss by thermogravimetry (TGA). X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray fluorescence spectroscopy (EDX) measurements confirmed the presence of hydrocarbon compounds on the silica surface after plasma modification. The acetylene plasma modified silica with the highest deposition level was selected to be incorporated into the PP/POE blends matrix. X-ray diffraction (XRD) showed that there is no new crystal phase formation in the PP/POE blends nanocomposites after addition of the acetylene plasma modified silica. Differential scanning calorimetry results (DSC) show two melting peaks and two crystallization peaks of the PP/POE blends nanocomposites corresponding to the PP and POE domains. The improved dispersion of the silica after acetylene plasma modification in the PP/POE blends matrix was shown by means of SEM-EDX mapping. Thermally stimulated depolarization current (TSDC) measurements confirm that addition of the acetylene plasma modified silica affects the charge trapping density and decreases the amount of injected charges into PP/POE blends nanocomposites. This work shows that acetylene plasma modification of the silica surface is a promising route to tune charge trapping properties of PP/POE blend-based nanocomposites.

18.
Adv Sci (Weinh) ; 6(21): 1901341, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31728285

RESUMO

A large number of current chemotherapeutic agents prevent the growth of tumors by inhibiting DNA synthesis of cancer cells. It has been found recently that many planar polycyclic aromatic hydrocarbons (PAHs) derivatives, previously known as carcinogenic, display anticancer activity through DNA cross-linking. However, the practical use of these PAHs is substantially limited by their low therapeutic efficiency and selectivity toward most tumors. Herein, the anticancer property of a nonplanar PAH named [4]helicenium, which exhibits highly selective cytotoxicity toward liver, lung cancer, and leukemia cells compared with normal cells, is reported. Moreover, [4]helicenium effectively inhibits tumor growth in liver cancer-bearing mice and shows little side effects in normal mice. RNA sequencing and confirmatory results demonstrate that [4]helicenium induces more DNA damage in tumor cells than in normal cells, resulting in tumor cell cycle arrest and apoptosis increment. This study reveals an unexpected role and molecular mechanism for PAHs in selectively killing tumor cells and provides an effective strategy for precision cancer therapies.

19.
Front Immunol ; 10: 2284, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616442

RESUMO

Autoimmune diseases are a physiological state wherein immune responses are directed against and damage the body's own tissues. Cytokines secreted by infiltrated inflammatory cells contribute to the pathogenesis of autoimmune diseases. TIPE2, one of the four family members of Tumor necrosis factor-α induced protein-8 (TNFAIP8), is a negative regulator of innate and adaptive immunity and plays essential roles in the maintenance of immune tolerance. However, studies on the role of TIPE2 during the development of autoimmune diseases have generated contradictory results. In the current study, we sought to determine the role of TIPE2 during the development of IMQ-induced psoriasis and Experimental Autoimmune Uveitis (EAU) in mice. Our study revealed that, while TIPE2-deficiency alleviates psoriasis, it exacerbates the development of EAU. Further studies demonstrated that, although TIPE2-deficient T cells produced more IL-17A, they do not migrate efficiently to the local inflammatory site, i.e., the skin. This in turn led to the decreased IL-17A production in the skin and consequently reduced the severity of psoriasis in TIPE2-deficient mice. However, although TIPE2-deficient T cells still produced more IL-17A in EAU model, they migrate into the inflamed eye as efficient as TIPE2-sufficient T cells, and consequently exacerbates the development of EAU in TIPE2-deficient mice. Taken together, these results indicate that TIPE2 may either promote or suppress autoimmunity depending on the specific inflammatory microenvironment in different types of autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Movimento Celular/imunologia , Microambiente Celular/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Linfócitos T/imunologia , Uveíte/imunologia , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/patologia , Movimento Celular/genética , Microambiente Celular/genética , Modelos Animais de Doenças , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Interleucina-17/genética , Interleucina-17/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Camundongos , Camundongos Knockout , Linfócitos T/patologia , Uveíte/genética , Uveíte/patologia
20.
Nanoscale Res Lett ; 14(1): 217, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31243604

RESUMO

Unmethylated CpG oligodeoxynucleotides are potent immunostimulatory motifs in activating both innate and acquired immune system by inducing Th1 type antigen-specific T cell responses, but their instability in serum greatly influences their immunostimulant efficiency. Here, we constructed a novel immuno-DNA nanohydrogels consisting of tandem repeat sequences of CpG units named CpG-MCA nanohydrogels through multi-primed chain amplification. CpG-MCA nanohydrogels were proved to resist degradation and increase the proliferation and migration of murine macrophage-like RAW264.7 cells. Furthermore, CpG-MCA nanohydrogels effectively induced high expression of tumor necrosis factor-α and interleukin-6, and remarkably inhibited the proliferation of U251 cells, suggesting that CpG-MCA nanohydrogels are expected to be employed as the potent anti-cancer immunostimulant.

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