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1.
Proc Natl Acad Sci U S A ; 120(34): e2120771120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579137

RESUMO

The binding of tumor necrosis factor-like cytokine 1A (TL1A) to death receptor 3 (DR3) plays an important role in the interaction between dendritic cells (DCs) and T cells and contributes to intestinal inflammation development. However, the mechanism by which DCs expressing TL1A mediate helper T (Th) cell differentiation in the intestinal lamina propria (LP) during the pathogenesis of inflammatory bowel disease remains unclear. In this study, we found that TL1A/DR3 promoted Th1 and Th17 cell differentiation in T-T and DC-T cell interaction-dependent manners. TL1A-deficient CD4+ T cells failed to polarize into Th1/Th17 cells and did not cause colonic inflammation in a T cell transfer colitis model. Notably, TL1A was located in the cytoplasm and nuclei of DCs, positively regulated the DC-specific ICAM-grabbing nonintegrin/RAF1/nuclear factor κB signaling pathway, enhanced the antigen uptake ability of DCs, and promoted TLR4-mediated DC activation, inducing naive CD4+ T cell differentiation into Th1 and Th17 cells. Our work reveals that TL1A plays a regulatory role in inflammatory bowel disease pathogenesis.


Assuntos
Doenças Inflamatórias Intestinais , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Humanos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Inflamação/metabolismo , Fator de Necrose Tumoral alfa
2.
Exp Cell Res ; 438(2): 114058, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38688434

RESUMO

BACKGROUND: Gastric cancer (GC) is a common cancer type with both high incidence and mortality. Recent studies have revealed an important role of circRNA in the development of GC. However, more experiments are needed to reveal the precise molecular mechanisms of circRNA in GC development. METHODS: Bioinformatics analysis was conducted to predict the potential role of circ_PABPC1 in GC and the target proteins of circ_PABPC1. Quantitative RT-PCR, Western blot and immunohistochemistry assays were conducted to detect the levels of circ_PABPC1, NF-κB p65, NF-κB p65 (Ser536) and ILK. MTT, Edu staining, cell scratch-wound and trans-well assays were carried out to detect cell proliferation, migration and invasion. The interaction between ILK and circ_PABPC1 was confirmed by RNA immunoprecipitation (RIP), RNA pull-down and fluorescence in situ hybridization assays. Genetically modified GC cells were injected into mice to evaluate the tumor growth performance. RESULTS: This study found that the high expression of circ_PABPC1 was associated with a poor prognosis of GC. The up-regulation of circ_PABPC1 promoted the proliferation, migration and invasion of GC cells. Circ_PABPC1 bound to ILK protein, thereby preventing the degradation of ILK. ILK mediated the effect of circ_PABPC1 on GC cells through activating NF-κB. CONCLUSION: circ_PABPC1 promotes the malignancy of GC cells through binding to ILK to activate NF-κB signaling pathway.


Assuntos
Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , NF-kappa B , Proteínas Serina-Treonina Quinases , RNA Circular , Transdução de Sinais , Neoplasias Gástricas , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , RNA Circular/genética , RNA Circular/metabolismo , Proliferação de Células/genética , Animais , Camundongos , NF-kappa B/metabolismo , NF-kappa B/genética , Movimento Celular/genética , Linhagem Celular Tumoral , Camundongos Nus , Masculino , Prognóstico , Feminino , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Pessoa de Meia-Idade , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelA/genética
3.
Drug Resist Updat ; 73: 101037, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38171078

RESUMO

Chaperone-mediated autophagy (CMA), a proteolytic system contributing to the degradation of intracellular proteins in lysosomes, is upregulated in tumors for pro-tumorigenic and pro-survival purposes. In this study, bioinformatics analysis revealed the co-occurrence of upregulated CMA and PD-L1 accumulation in metastatic melanoma with adaptive immune resistance (AIR) to anti-PD1 treatment, suggesting the potential therapeutic effects of rewiring CMA for PD-L1 degradation. Furthermore, this co-occurrence is attributed to IFN-γ-mediated compensatory up-regulation of PD-L1 and CMA, accompanied by enhanced macropinocytosis. Drawing inspiration from the cellular uptake of prions via macropinocytosis, a prion-like chemical inducer of proximity called SAP was engineered using self-assembly of the designed chiral peptide PHA. By exploiting sensitized macropinocytosis, SAP clandestinely infiltrates tumor cells and subsequently disintegrates into PHA, which reprograms CMA by inducing PD-L1 close to HSPA8. SAP degrades PD-L1 in a CMA-dependent manner and effectively restores the anti-tumor immune response in both allografting and Hu-PDX melanoma mouse models with AIR while upholding a high safety profile. Collectively, the reported SAP not only presents an immune reactivation strategy with clinical translational potential for overcoming AIR in cutaneous melanomas but serves as a reproducible example of precision-medicine-guided drug development that fully leverages specific cellular indications in pathological states.


Assuntos
Autofagia Mediada por Chaperonas , Melanoma , Príons , Camundongos , Animais , Antígeno B7-H1/metabolismo , Melanoma/metabolismo , Príons/metabolismo , Lisossomos/metabolismo
4.
Opt Lett ; 48(24): 6553-6556, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099797

RESUMO

We present and experimentally evaluate the use of transfer learning to address experimental data scarcity when training neural network (NN) models for Mach-Zehnder interferometer mesh-based optical matrix multipliers. Our approach involves pretraining the model using synthetic data generated from a less accurate analytical model and fine-tuning it with experimental data. Our investigation demonstrates that this method yields significant reductions in modeling errors compared to using an analytical model or a standalone NN model when training data is limited. Utilizing regularization techniques and ensemble averaging, we achieve <1 dB root-mean-square error on the 3×3 matrix weights implemented by a photonic chip while using only 25% of the available data.

5.
Molecules ; 28(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37241993

RESUMO

Artemisia divaricate belongs to the Artemisia genus of the family of Compositae, a sort of perennial herb endemic in most regions of China. For the first time, a phytochemical investigation was carried out on the whole plant of Artemisia divaricate, resulting in the identification of 39 sesquiterpenes, with 9 of them being new (1-9). The structures of the new compounds were fully established using extensive analysis of MS and 1D and 2D NMR spectroscopic data and density functional theory (DFT) NMR calculations. Their structures involve germacrane, eudesmane, and bisabolane types. All the new isolates were evaluated for their anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated murine macrophages of RAW 264.7 cells. Compounds 2 and 8 showed a significant inhibition effect on NO production, with IC50 values of 5.35 ± 0.75 and 7.68 ± 0.54 µM, respectively.


Assuntos
Artemisia , Sesquiterpenos , Animais , Camundongos , Artemisia/química , Macrófagos , Compostos Fitoquímicos/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Estrutura Molecular
6.
BMC Oral Health ; 23(1): 351, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268939

RESUMO

OBJECTIVE: The aim was to investigate the prevalence and clinical and 3-dimensional (3D) radiographic characteristics of supernumerary teeth (ST) in a paediatric dental population. The factors associated with ST eruption potential were analysed, and the optimal extraction time for nonerupted ST was discussed. METHODS: A retrospective study was performed in a 13,336-participant baseline population aged 3-12 years for whom panoramic radiographs had been obtained in the hospital from 2019 to 2021. The medical records and radiographic data were reviewed to identify patients with ST. Both the demographic variables and ST characteristics were recorded and analysed . RESULTS: In total, 890 patients with 1,180 ST were screened from the 13,336 baseline population. The ratio of males (679) to females (211) was approximately 3.2:1. Generally, ST occurred singularly and were frequently found in the maxilla (98.1%). A total of 40.8% of ST were erupted, and the 6-year-old age group presented the highest eruption rate (57.8%). The eruption rate of ST was highly negatively correlated with age. A total of 598 patients additionally underwent cone- beam computed tomography (CBCT). According to the CBCT images, the majority of ST were conical, normally oriented, palatally situated, nonerupted and symptomatic. The most common ST-associated complication was failed eruption of adjacent teeth. In addition, symptomatic ST were more common in the 7- to 8- and 9- to 10-year-old age groups. The eruption rate of ST was 25.3% among the patients who had undergone CBCT. A normal orientation and the labial position were significant protective factors for ST eruption, with odds ratios (ORs) of 0.004 (0.000-0.046) and 0.086 (0.007-1.002), respectively. Age and the palatal position were significant risk factors, with ORs of 1.193 (1.065-1.337) and 2.352 (1.377-4.02), respectively. CONCLUSIONS: This study provides a detailed analysis of ST characteristics in 3-12 year old children. Age as well as the position and orientation of ST were reliable predictors of the ST eruption. An age of 6 years old may be the optimal time for extraction of nonerupted ST to maximize the utilization of eruption potential and reduce the incidence of ST-associated complications.


Assuntos
Dente Supranumerário , Masculino , Criança , Feminino , Humanos , Pré-Escolar , Dente Supranumerário/diagnóstico por imagem , Dente Supranumerário/epidemiologia , Estudos Retrospectivos , Prevalência , Tomografia Computadorizada de Feixe Cônico/métodos , Maxila/diagnóstico por imagem , China/epidemiologia
7.
Nanotechnology ; 32(50)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34404036

RESUMO

Increasing the specific surface area and the amount of doping heteroatoms is an effective means to improve the electrochemical properties of carbon nanotubes (CNTs). The usual activation method makes it difficult for the retention of the heteroatoms while enlarging the specific surface area, and it can be found from literatures that specific surface area and S-content of carbon-based electrode materials are mutually exclusive. Here, CNTs with high specific surface area and sulfur content are constructed by simple activation of sulfonated polymer nanotubes with KHCO3, and the excellent electrochemical performance can be explained by the following points: first, KHCO3can be decomposed into K2CO3, CO2and H2O during the activation process. The synergistic action of physical activation (CO2and H2O) and chemical activation (K2CO3) equips the electrode material with high specific surface area of 1840 m2g-1and hierarchical micro/mesopores, which is beneficial to its double-layer capacitance. Second, compared with reported porous CNTs prepared by chemical activation (KOH) or physical activation (CO2or H2O), the mild activator KHCO3makes the sulfur content at a high level of 4.6 at%, which is very advantageous for high pseudocapacitance performance.

8.
Nano Lett ; 20(8): 5844-5852, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32589431

RESUMO

The design of bioactive supramolecular chirality is always hampered by the lack of feasible schemes to assigned specific biological activities. Herein, we developed a "mirror-image peptide grafting" method to graft the epitopes of bioactive d-peptide onto the miniprotein template to construct a self-assembled supraparticle. Grafting DPMIß, a 12-mer d-enantiomeric peptide functioned as the p53 agonist, onto Apamin, we successfully constructed a self-assembled d-enantiomeric miniprotein supermolecule nanoparticle, termed DMSN. This chiral supraparticle possesses a favorable pharmaceutical profile including the passive tumor targeting, cell membrane penetration, intracellular reductive responsiveness, and endosome escaping. DMSN showed in vitro and in vivo p53-dependent antiproliferative activity and augmented antitumor immunity elicited by anti-PD1 therapy. This enabling strategy will allow us to fabricate a class of peptide/protein-derived supramolecular chirality with predictable biological activities and will likely have a broad impact on the chiral nanotechnology at the service of prevention and treatment of human diseases.


Assuntos
Nanopartículas , Nanotecnologia , Humanos , Imunoterapia , Peptídeos , Estereoisomerismo
9.
BMC Oral Health ; 21(1): 319, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172026

RESUMO

BACKGROUND: Supragingival plaque and saliva are commonly used for microbiome analysis. Many epidemiological studies have identified deciduous teeth caries as a risk factor for caries development in first permanent molar (FPM); nevertheless, to the best of our knowledge, there are no reports on the effects of deciduous teeth caries on the microbiome of healthy FPM. Additionally, it remains unclear whether saliva can be used instead of supragingival plaque for caries microbial studies. Therefore, we aimed to elucidate this issue, and to characterize and compare the oral microbiome of healthy FPMs in children with different caries statuses and that from children with and without caries in a similar microhabitat, by PacBio sequencing. Currently, few studies have investigated the oral microbiome of children using this technique. METHODS: Thirty children (aged 7-9 years) with mixed dentition were enrolled; 15 had dental caries, and 15 did not. Supragingival plaques of deciduous molars and maxillary FPMs, and non-stimulating saliva samples were collected. DNA was extracted and the v1-v9 regions of 16S rRNA were amplified. Subsequently, PacBio sequencing and bioinformatic analyses were performed for microbiome identification. RESULTS: The microbial alpha diversity of the saliva samples was lower than that of the supragingival plaque (p < 0.05); however, no differences were detected between deciduous teeth and FPMs (p > 0.05). In addition, the alpha and beta diversity of children with and without caries was also similar (p > 0.05). Nonmetric multidimensional scaling and Adonis analyses indicated that the microbial structure of salivary and supragingival plaque samples differ (p < 0.05). Further analysis of deciduous teeth plaque showed that Streptococcus mutans, Propionibacterium acidifaciens, and Veillonella dispar were more abundant in children with caries than in those without (p < 0.05); while in FPMs plaque, Selenomonas noxia was more abundant in healthy children (p < 0.05). No differences in microorganisms abundance were found in the saliva subgroups (p > 0.05). CONCLUSION: We have determined that supragingival plaque was the best candidate for studying carious microbiome. Furthermore, S. mutans, V. dispar, and P. acidifaciens were highly associated with deciduous teeth caries. S. noxia may be associated with the abiding health of FPM; however, this requires additional studies.


Assuntos
Cárie Dentária , Microbiota , Criança , Estudos Transversais , Suscetibilidade à Cárie Dentária , Dentição Mista , Humanos , Propionibacterium , RNA Ribossômico 16S , Saliva , Selenomonas , Veillonella
10.
Histochem Cell Biol ; 153(3): 153-164, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31845005

RESUMO

The objective of this study is to investigate the expression of enzymes involved in the sulfation of articular cartilage from proximal metacarpophalangeal (PMC) joint cartilage and distal metacarpophalangeal (DMC) joint cartilage in children with Kashin-Beck disease (KBD). The finger cartilage samples of PMC and DMC were collected from KBD and normal children aged 5-14 years old. Hematoxylin and eosin staining as well as immunohistochemical staining were used to observe the morphology and quantitate the expression of carbohydrate sulfotransferase 3 (CHST-3), carbohydrate sulfotransferase 12 (CHST-12), carbohydrate sulfotransferase 13 (CHST-13), uronyl 2-O-sulfotransferase (UST), and aggrecan. In the results, the numbers of chondrocyte decreased in all three zones of PMC and DMC in the KBD group. Less positive staining cells for CHST-3, CHST-12, CHST-13, UST, and aggrecan were observed in almost all three zones of PMC and DMC in KBD. The positive staining cell rates of CHST-12 were higher in superficial and middle zones of PMC and DMC in KBD, and a significantly higher rate of CHST-13 was observed only in superficial zone of PMC in KBD. In conclusion, the abnormal expression of chondroitin sulfate sulfotransferases in chondrocytes of KBD children may provide an explanation for the cartilage damage, and provide therapeutic targets for the treatment.


Assuntos
Cartilagem Articular/enzimologia , Doença de Kashin-Bek/enzimologia , Sulfotransferases/biossíntese , Adolescente , Agrecanas/análise , Agrecanas/biossíntese , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Criança , Feminino , Humanos , Doença de Kashin-Bek/metabolismo , Doença de Kashin-Bek/patologia , Masculino , Sulfotransferases/análise , Carboidrato Sulfotransferases
11.
Cancer Cell Int ; 20: 267, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32595416

RESUMO

BACKGROUND: Alpha protein kinase 2 (ALPK2) was known to play a vital role in cancer by regulating cell cycle and DNA repair. Ovarian cancer (OC) is one of the most lethal malignancies in the female reproductive system. The emphasis of this study is to explore the role of ALPK2 in OC. METHODS: Firstly, tumor and normal tissues were collected for detecting expression of ALPK2 in OC. Lentivirus-mediated shRNA knockdown of ALPK2 was used to construct OC cell model, which was verified by qRT-PCR and Western blot. The cell proliferation was detected by MTT, cell cycle and apoptosis were measured through flow cytometry. Wound-healing assay was conducted to detect the migration of OC cells. RESULTS: It was proved that the expression of ALPK2 in OC tissues was significantly higher than that in normal ovarian tissues. Moreover, knockdown of ALPK2 could inhibit proliferation, migration and promote apoptosis, arrested cell cycle of OC cells. It was also found that ALPK2 knockdown inhibited tumor growth in xenograft mice in vivo. Furthermore, ALPK2 was involved in OC cells via regulating EMT-related proteins (N-cadherin, Vimentin and Snail), inhibiting apoptosis-related proteins (Bcl-2, Bcl-w, HSP27, HSP60, IGF-I, IGF-1sR, Survivin and XIAP), as well as the regulation of downstream pathways (Akt, p-Akt, Cyclin D1, CDK6 and PIK3CA). CONCLUSIONS: In conclusion, ALPK2 might serve as an optional target for prognosis and therapeutic of OC patients.

12.
Nano Lett ; 19(12): 8708-8715, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31744296

RESUMO

Immune checkpoint blockade therapies fail to induce immune response in the vast majority of cancer patients, so developing robust adjuvants for increasing tumor immune response is central for effective tumor immunotherapy. The Wnt/ß-catenin pathway is a crucial oncogenic signal in relation to tumor immune evasion; however, none of the Wnt inhibitor under clinical or preclinical phases has demonstrated satisfactory specificity. Thus, new compounds or modalities that tumor specifically modulate the Wnt signal will be of great significance and value in clinical tumor immunotherapy. Herein, inspired by a natural phenomenon in cancer cells that the Achilles' Heel of oncoprotein ß-catenin, H1 helix, predisposes ß-catenin to oligomerization for proteasomal degradation and can be exacerbated by carnosic acid (CA, a Wnt inhibitor), we developed a size-tuned nanocluster (CAcluster) with well-defined supramolecular nanostructure by coassembling CA and H1 peptide. With the inherent enhanced permeability and retention (EPR) effect and the designed tumor microenvironment (TME) responsiveness, the CAcluster tumor specifically suppress the Wnt/ß-catenin cascade in vivo, while maintaining a highly favorable biosafety profile. More importantly, the CAclusterin vivo improved the tumor response to the PD1/PD-L1 immune checkpoint blockade in melanoma and colon cancer. This study provides new insights into the biomimetic coassembly strategy to design supramolecular nanostructured adjuvants for hazard-free Wnt suppression and synergy with tumor immunotherapy.


Assuntos
Materiais Biomiméticos , Sistemas de Liberação de Medicamentos , Imunoterapia , Melanoma Experimental/terapia , Nanoestruturas/química , Proteínas de Neoplasias , beta Catenina , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Linhagem Celular Tumoral , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/antagonistas & inibidores , beta Catenina/metabolismo
13.
Nano Lett ; 19(11): 7918-7926, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31645103

RESUMO

Intracellular protein-protein interactions (PPIs) are a vital and yet underexploited class of therapeutic targets for their crucial roles in cellular processes and involvement in disease initiation and progression. Although some successful chemistry and nanotechnologies have been introduced into peptide PPI modulators to allow cell and tissue permeability, significant challenges remain with regard to the efficient and precise modulation of PPIs within specific cells of diseased tissues, such as solid tumors. Herein, an intratumoral transformable hierarchical framework, termed iPLF, was fabricated via a two-step self-assembly between peptides and lanthanide-doped nanocrystals. In this proof-of-concept study, using NanoEL effect, TME response, and tumor marker targeting, iPLF in vivo delivered the p53-MDM2 modulator DPMI into tumor cells and ß-catenin-Bcl9 modulator Bcl9p into tumor stem cells. This crafted programmed nanomedicine with triple-stage delivery and responsiveness accurately modulated the specific intracellular protein-protein interactions, resulting in the suppression of tumor growth and metastasis in vivo, while maintaining a highly favorable safety profile. iPLF reached the goal of accurate, potent, and hazard-free intracellular PPI modulation, thereby providing a means to improve current knowledge of PPI networks and a novel therapeutic strategy for a great variety of diseases.


Assuntos
Antineoplásicos/farmacologia , Elementos da Série dos Lantanídeos/farmacologia , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Mapas de Interação de Proteínas/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Preparações de Ação Retardada/química , Desenho de Fármacos , Células HCT116 , Humanos , Elementos da Série dos Lantanídeos/química , Elementos da Série dos Lantanídeos/uso terapêutico , Camundongos , Nanomedicina , Nanopartículas/química , Neoplasias/metabolismo , Neoplasias/patologia , Peptídeos/química , Peptídeos/uso terapêutico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , beta Catenina/metabolismo
14.
Angew Chem Int Ed Engl ; 59(35): 15209-15214, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32432349

RESUMO

Radio-photoluminescence (RPL) materials display a distinct radiation-induced permanent luminescence center, and therefore find application in the detection of ionizing radiation. The current inventory of RPL materials, which were discovered by serendipity, has been limited to a small number of metal-ion-doped inorganic materials. Here we document the RPL of a metal-organic framework (MOF) for the first time: X-ray induced free radicals are accumulated on the organic linker and are subsequently stabilized in the conjugated fragment in the structure, while the metal center acts as the X-ray attenuator. These radicals afford new emission features in both UV-excited and X-ray excited luminescence spectra, making it possible to establish linear relationships between the radiation dose and the normalized intensity of the new emission feature. The MOF-based RPL materials exhibit advantages in terms of the dose detection range, reusability, emission stability, and energy threshold. Based on a comprehensive electronic structure and energy diagram study, the rational design and a substantial expansion of candidate RPL materials can be anticipated.

15.
J Am Chem Soc ; 141(20): 8030-8034, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31064178

RESUMO

Semiconductive metal-organic frameworks (MOFs) have attracted extraordinary research interest in recent years; however, electronic applications based on these emerging materials are still in their infancy. Herein, we show that a lanthanide-based semiconductive MOF (SCU-12) can effectively convert X-ray photons to electrical current signals under continuous hard X-ray radiation. The semiconductive MOF-based polycrystalline detection device presents a promising X-ray sensitivity with the value of 23.8 µC Gyair-1 cm-2 under 80 kVp X-ray exposure, competitive with the commercially available amorphous selenium (α-Se) detector. The lowest detectable X-ray dose rate is 0.705 µGy s-1, representing the record value among all X-ray detectors fabricated by polycrystalline materials. This work discloses the first demonstration of hard radiation detection by semiconductive MOFs, providing a horizon that can guide the synthesis of a new generation of radiation detection materials by taking the advantages of structural designability and property tunability in the MOF system.

16.
Biosci Biotechnol Biochem ; 83(3): 446-455, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30387379

RESUMO

Aluminum (Al) toxicity is a primary limiting factor for crop production in acid soils. Callose deposition, an early indicator and likely a contributor to Al toxicity, is induced rapidly in plant roots under Al stress. SbGlu1, encoding a ß-1,3-glucanase for callose degradation, showed important roles in sorghum Al resistance, yet its regulatory mechanisms remain unclear. The STOP1 transcription factors mediate Al signal transduction in various plants. Here, we identified their homolog in sweet sorghum, SbSTOP1, transcriptionally activated the expression of SbGlu1. Moreover, the DNA sequence recognized by SbSTOP1 on the promoter of SbGlu1 lacked the reported cis-acting element. Complementation lines of Atstop1 with SbSTOP1 revealed enhanced transcription levels of SbGlu1 homologous gene and reduced callose accumulation in Arabidopsis. These results indicate, for the first time, that SbSTOP1 is involved in the modulation of callose deposition under Al stress via transcriptional regulation of a ß-1,3-glucanase gene.


Assuntos
Alumínio/toxicidade , Glucana 1,3-beta-Glucosidase/genética , Glucanos/metabolismo , Proteínas de Plantas/metabolismo , Sorghum/efeitos dos fármacos , Sorghum/fisiologia , Transcrição Gênica/efeitos dos fármacos , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Células HEK293 , Humanos , Regiões Promotoras Genéticas/genética , Sorghum/genética , Sorghum/metabolismo
17.
J Mater Sci Mater Med ; 30(7): 76, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31218573

RESUMO

Superparamagnetic iron oxide nanoparticles (SPION) were widely employed as targeted drug delivery platform due to their unique magnetic property and effortless surface modification. However, the lack of targeting accuracy has been a big obstacle for SPION used in precise medicine. Herein, the tumor-targeting of SPION was enhanced by the conjugation of an aptamer-hybridized nucleic acid structure. The aptamer modified on the surface of SPION was composed of a double-stranded DNA (dsDNA) and a G-quadruplex DNA (AS1411) structure, which carried a chemical anticancer drug, daunomycin (DNM) and a photosensitizer molecule, namely 5, 10, 15, 20-tetra (phenyl-4-N-methyl-4-pyridyl) porphyrin (TMPyP), respectively. The aptamer-dsDNA conjugated SPION nanocarriers (named Apt-S8@SPION) exhibited good stability in serum and nuclease DNase I. The drug-loaded nanocarriers (TMPyP&DNM&Apt-S8@SPION) have high cellular cytotoxicity to A549 and C26 cells which are represently nucleolin-overexpressing cancer cells. The nucleolin-blocking experiments unambiguously evidenced that the formed nanomedicine could target to the cell surface via the specific AS1411-nucleolin interaction, which increased the efficiency of cell uptake. Meanwhile, the TMPyP&DNM&Apt-S8@SPION nanospheres could produce cytotoxic reactive oxygen species efficiently by irradiation of visible light for establishing a new type of PDT to cancer cells. Therefore, the designed TMPyP&DNM&Apt-S8@SPION nanoparticles have magnetic-aptamer dual targeting and combined chemo-photodynamic therapy, and thus were supposed to be ideal drug delivery vehicles with great potential in the era of precision medicine.


Assuntos
Sistemas de Liberação de Medicamentos , Compostos Férricos/química , Nanopartículas de Magnetita/química , Fotoquimioterapia/métodos , Células A549 , Antineoplásicos/farmacologia , Aptâmeros de Nucleotídeos/química , Movimento Celular , Daunorrubicina/química , Quadruplex G , Humanos , Hibridização de Ácido Nucleico , Oligonucleotídeos/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química
18.
Molecules ; 24(9)2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060332

RESUMO

Hair-coloring products include permanent, semi-permanent and temporary dyes that vary by chemical formulation and are distinguished mainly by how long they last. Domestic temporary hair dyes, such as fuchsin basic, basic red 2 and Victoria blue B, are especially popular because of their cheapness and facile applications. Despite numerous studies on the relationship between permanent hair dyes and disease, there are few studies addressing whether these domestic temporary hair dyes are associated with an increased cancer risk. Herein, to ascertain the bio-safety of these temporary hair dyes, we comparatively studied their percutaneous absorption, hemolytic effect and cytotoxic effects in this paper. Furthermore, to better understand the risk of these dyes after penetrating the skin, experimental and theoretical studies were carried out examining the interactions between the dyes and serum albumins as well as calf thymus (CT)-DNA. The results showed that these domestic temporary hair dyes are cytotoxic with regard to human red blood cells and NIH/3T3 cell lines, due to intense interactions with bovine serum albumin (BSA)/DNA. We conclude that the temporary hair dyes may have risk to human health, and those who use them should be aware of their potential toxic effects.


Assuntos
Eritrócitos/citologia , Tinturas para Cabelo/efeitos adversos , Células NIH 3T3/citologia , Corantes de Rosanilina/efeitos adversos , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Tinturas para Cabelo/química , Tinturas para Cabelo/farmacocinética , Hemólise , Humanos , Camundongos , Simulação de Acoplamento Molecular , Células NIH 3T3/efeitos dos fármacos , Fenazinas/efeitos adversos , Fenazinas/química , Fenazinas/farmacocinética , Corantes de Rosanilina/química , Corantes de Rosanilina/farmacocinética , Albumina Sérica Humana/efeitos dos fármacos , Suínos
19.
J Nanosci Nanotechnol ; 18(7): 4445-4456, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442618

RESUMO

The dose-dependent toxicity and low specificity against cancerous cells have restricted the clinical use of daunomycin (DNM). Titanium dioxide (TiO2) has been wildly used as an inorganic photodynamic therapy (PDT) agent and drug carrier. To facilitate the targeted drug delivery and combined therapy, in the present study, TiO2-coated Fe3O4 nanoparticles (Fe3O4@TiO2 NPs) were employed to load DNM and the drug-loaded Fe3O4@TiO2-DNM Nps exhibited smart pH-controlled releasing and satisfactory cytotoxicity as well as photocytotocity. The combination of prussian blue staining and fluorescence methods evidenced the effortless cell internalization of the fabricated Fe3O4@TiO2-DNM Nps for the cancer cells. The cell cycle status experiments indicated that the as-prepared nanospheres arrested the S and G2/M periods of the cancer cell proliferation in the dark, and further induced the apoptosis under the irradiation of ultraviolet light. The cell apoptotic results revealed that the apoptosis induced by the Fe3O4@TiO2-DNM Nps was in the early stage. The constructed Fe3O4@TiO2-DNM NPs have been endowed with multifunctions that allow them to selectively deliver combinatorial therapeutic payload and exhibit integrated therapeutic effectiveness to tumors.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Daunorrubicina/farmacologia , Nanosferas , Fotoquimioterapia , Titânio , Antibióticos Antineoplásicos/química , Daunorrubicina/química
20.
Opt Express ; 25(11): 12455-12462, 2017 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-28786601

RESUMO

We introduce and experimentally demonstrate a flexible temporal illusion at telecommunication data rate in optical fiber communication system. The temporal illusion cannot only transform an event to another event as expected, but also mask the event with high-level signal, providing a novel method to conceal the confidential information. We successfully transform the output temporal waveforms of a return-to-zero (RZ), dark RZ and nonreturn-to-zero (NRZ) event into that of any above modulation format event and high-level signal at different illusion bits and mosaic bits at a data rate of 5 Gb/s, respectively. Our works offer us new perspectives on illusion optics for falsifying event rather than object, which has potential applications in secure communication, data encryption and other military applications.

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