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1.
Parasit Vectors ; 16(1): 134, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072796

RESUMO

BACKGROUND: Insulin-like signaling (IS) in insects is a conserved pathway that regulates development, reproduction and longevity. Insulin-like peptides (ILPs) activate the IS pathway by binding to the insulin receptor (InR) and trigger the ERK and AKT cascades. A varying number of ILPs were identified in Aedes aegypti mosquito and other insects. Aedes albopictus is an invasive mosquito which transmits dengue and Zika viruses worldwide. Until now, the molecular and expression characteristics of IS pathway in Ae. albopictus have not been investigated. METHODS: The orthologues of ILP in Ae. albopictus genome assembly was analyzed by using sequence blast. Phylogenetic analysis and molecular characterization were performed to identify the functional domains of ILPs. Quantitative analysis was performed to determine the expression characteristics of ILPs, InR as well as ERK and AKT in mosquito development and different tissues of female adults after blood-feeding. In addition, the knockdown of InR was achieved by feeding larvae with Escherichia coli-producing dsRNA to investigate the impact of IS pathway on mosquito development. RESULTS: We identified seven putative ILP genes in Ae. albopictus genome assembly, based on nucleotide similarity to the ILPs of Ae. aegypti and other insects. Bioinformatics and molecular analyses suggested that the ILPs contain the structural motif which is conserved in the insulin superfamily. Expression levels of ILPs, InR as well as ERK and AKT varied in Ae. albopictus development stages and between male and female adults. Quantitative analyses revealed that expression of ILP6, the putative orthologue of the insulin growth factor peptides, was highest in the midgut of female adults after blood-feeding. Knockdown of Ae. albopictus InR induces a significant decrease in the phosphorylation levels of ERK and AKT proteins and results in developmental delays and smaller body sizes. CONCLUSIONS: The IS pathway of Ae. albopictus mosquito contains ILP1-7, InR and ERK/AKT cascades, which exhibited different developmental and tissue expression characteristics. Feeding Ae. albopictus larvae with E. coli-producing InR dsRNA blocks the ERK and AKT cascades and interferes with the development of mosquito. Our data suggest that IS pathway plays an important role in the metabolism and developmental process and could represent a potential target for controlling mosquito-borne diseases.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Masculino , Feminino , Aedes/fisiologia , Insulina , Proteínas Proto-Oncogênicas c-akt/genética , Filogenia , Escherichia coli/genética , Escherichia coli/metabolismo , Peptídeos/genética , Mosquitos Vetores/fisiologia
2.
Adv Healthc Mater ; 12(12): e2202907, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36802128

RESUMO

Aggregation-induced emission luminogens (AIEgens) are widely used as photosensitizers for image-guided photodynamic therapy (PDT). Due to the limited penetration depth of light in biological tissues, the treatments of deep-seated tumors by visible-light-sensitized aggregation-induced emission (AIE) photosensitizers are severely hampered. Microwave dynamic therapy attracts much attention because microwave irradiation can penetrate very deep tissues and sensitize the photosensitizers to generate reactive oxygen species (ROS). In this work, a mitochondrial-targeting AIEgen (DCPy) is integrated with living mitochondria to form a bioactive AIE nanohybrid. This nanohybrid can not only generate ROS under microwave irradiation to induce apoptosis of deep-seated cancer cells but also reprogram the metabolism pathway of cancer cells through retrieving oxidative phosphorylation (OXPHOS) instead of glycolysis to enhance the efficiency of microwave dynamic therapy. This work demonstrates an effective strategy to integrate synthetic AIEgens and natural living organelles, which would inspire more researchers to develop advanced bioactive nanohybrids for cancer synergistic therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Micro-Ondas , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico
3.
Colloids Surf B Biointerfaces ; 211: 112295, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34952286

RESUMO

Photothermal therapy (PTT) induced by near-infrared (NIR) laser has attracted much attention for the innovation of tumor therapy, in which the photothermal agent with good biocompatibility and high efficiency is the prerequisite. Herein, the biocompatible bovine serum albumin (BSA) coated Ag2S nanoparticles (NPs) as photothermal agent were synthesized directly at mild temperature for PTT of cancer. The high photothermal conversion efficiency of the obtained Ag2S NPs with strong NIR absorption is about 18.89%, which make them ideal materials for photothermal agents. Furthermore, the Ag2S NPs can induce effective apoptosis of tumor cells exposed to an NIR laser (808 nm), realizing an effective PTT with excellent killing effect of tumor cells. This work provides a simple reproducible method to fabricate the water-soluble and biocompatible Ag2S NPs, which would provide new insights of designing new functional NPs for the PTT therapy of tumor.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/terapia , Fototerapia , Terapia Fototérmica , Soroalbumina Bovina
4.
Nanoscale Adv ; 3(2): 463-470, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36131748

RESUMO

Recently, multimodal imaging nanoprobes based on the complementary advantages of various imaging methods have attracted considerable attention due to their potential application in the biomedical field. As important bioimaging nanoprobes, lanthanide-doped nanocrystals (NCs) would be expected to improve the related biophotonic technology through integrated multimodal bioimaging. Herein, water-soluble and biocompatible NaYF4:Nd/NaDyF4 NCs were prepared by a solvothermal method combined with hydrophobic interaction with phospholipids as a capping agent. The NaYF4:Nd/NaDyF4 NCs exhibit excellent colloidal stability under physiological conditions. Compared with the bare NaYF4:Nd3+ NCs, the second near-infrared (NIR-II, 1000-1700 nm) fluorescence intensities of Nd3+ ions in the NaYF4:Nd/NaDyF4 core-shell NCs at the emissions of 1058 nm and 1332 nm are enhanced by 3.46- and 1.75-fold, respectively. Moreover, the r 2 value of NaYF4:Nd/NaDyF4 NCs as T 2-weighted contrast agents is calculated to be 44.0 mM-1 s-1. As a novel multimodal imaging nanoprobe, the NaYF4:Nd/NaDyF4 NCs can be employed for both NIR-II fluorescence and magnetic resonance imaging (MRI). The phospholipid-modified NaYF4:Nd/NaDyF4 NCs demonstrate in vitro and in vivo multimodal NIR-II fluorescence imaging and MRI of HeLa cells and tumors, respectively. This study provides an effective strategy for the development of novel multimodal probes for the medical application of nanomaterials.

5.
Biomed Opt Express ; 11(2): 971-981, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32206399

RESUMO

We demonstrate an automatic recognition strategy for terahertz (THz) pulsed signals of breast invasive ductal carcinoma (IDC) based on a wavelet entropy feature extraction and a machine learning classifier. The wavelet packet transform was implemented into the complexity analysis of the transmission THz signal from a breast tissue sample. A novel index of energy to Shannon entropy ratio (ESER) was proposed to distinguish different tissues. Furthermore, the principal component analysis (PCA) method and machine learning classifier were further adopted and optimized for automatic classification of the THz signal from breast IDC sample. The areas under the receiver operating characteristic curves are all larger than 0.89 for the three adopted classifiers. The best breast IDC recognition performance is with the precision, sensitivity and specificity of 92.85%, 89.66% and 96.67%, respectively. The results demonstrate the effectiveness of the ESER index together with the machine learning classifier for automatically identifying different breast tissues.

6.
Cell Rep ; 29(7): 1848-1861.e6, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31722202

RESUMO

Follicular regulatory T (TFR) cells are a specialized suppressive subset that controls the germinal center (GC) response and maintains humoral self-tolerance. The mechanisms that maintain TFR lineage identity and suppressive activity remain largely unknown. Here, we show that expression of Blimp1 by FoxP3+ TFR cells is essential for TFR lineage stability, entry into the GC, and expression of regulatory activity. Deletion of Blimp1 in TFR cells reduced FoxP3 and CTLA-4 expression and increased pro-inflammatory cytokines and spontaneous production of autoantibodies, including elevated IgE. Maintenance of TFR stability reflected Blimp1-dependent repression of the IL-23R-STAT3 axis and activation of the CD25-STAT5 pathway, while silenced IL-23R-STAT3 or increased STAT5 activation rescued the Blimp1-deficient TFR phenotype. Blimp1-dependent control of CXCR5/CCR7 expression also regulated TFR homing into the GC. These findings uncover a Blimp1-dependent TFR checkpoint that enforces suppressive activity and acts as a gatekeeper of GC entry.


Assuntos
Regulação da Expressão Gênica/imunologia , Centro Germinativo/imunologia , Fator 1 de Ligação ao Domínio I Regulador Positivo/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular , Centro Germinativo/citologia , Humanos , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/imunologia , Camundongos , Camundongos Transgênicos , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Receptores CCR7/genética , Receptores CCR7/imunologia , Receptores CXCR5/genética , Receptores CXCR5/imunologia , Receptores de Interleucina/genética , Receptores de Interleucina/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Transdução de Sinais/genética , Linfócitos T Reguladores/citologia
7.
Proc Natl Acad Sci U S A ; 115(26): 6780-6785, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29891681

RESUMO

Lineage commitment and differentiation into CD4+ T cell subsets reflect an interplay between chromatin regulators and transcription factors (TF). Follicular T cell development is regulated by the Bcl6 TF, which helps determine the phenotype and follicular localization of both CD4+ follicular helper T cells (TFH) and follicular regulatory T cells (TFR). Here we show that Bcl6-dependent control of follicular T cells is mediated by a complex formed between Bcl6 and the Mi-2ß-nucleosome-remodeling deacetylase complex (Mi-2ß-NuRD). Formation of this complex reflects the contribution of the intracellular isoform of osteopontin (OPN-i), which acts as a scaffold to stabilize binding between Bcl6 and the NuRD complex that together regulate the genetic program of both TFH and TFR cells. Defective assembly of the Bcl6-NuRD complex distorts follicular T cell differentiation, resulting in impaired TFR development and skewing of the TFH lineage toward a TH1-like program that includes expression of Blimp1, Tbet, granzyme B, and IFNγ. These findings define a core Bcl6-directed transcriptional complex that enables CD4+ follicular T cells to regulate the germinal center response.


Assuntos
Montagem e Desmontagem da Cromatina , Centro Germinativo/citologia , Linfopoese/fisiologia , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/fisiologia , Proteínas Proto-Oncogênicas c-bcl-6/fisiologia , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Reguladores/citologia , Animais , Linhagem da Célula , Regulação da Expressão Gênica/imunologia , Regulação da Expressão Gênica/fisiologia , Técnicas de Introdução de Genes , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/fisiologia , Osteopontina/biossíntese , Osteopontina/genética , Transcrição Gênica
8.
Exp Ther Med ; 15(2): 1666-1671, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29399135

RESUMO

The purpose of the present study was to explore the efficacy of arthroscopic loose body removal for knee osteoarthritis (KOA). A total of 23 patients with KOA were enrolled and randomly received conservative treatment (conservative group; n=10) or loose body removal surgery (surgery group; n=13). The serum levels of disease activity indices, including hypersensitive C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR) and synovial inflammatory factors [interleukin (IL)-1 and IL-6] were detected prior to surgery, and at 4 days, 2 or 4 weeks after surgery. All patients were followed up for 2 years and the cure rate was estimated. No significant difference was identified in pre-operative plasma levels of hs-CRP and ESR as well as the synovial concentration of IL-1 and IL-6 between the two groups (all P>0.05). At 2 and 4 weeks after treatment, the levels of these parameters in the surgery group were significantly lower than those in the conservative group (all P<0.05), although the maximum value of these parameters was higher in the surgery group than in the conservative group at 4 days after surgery. The cure rate for KOA in the surgery group was significantly higher than that in the conservative group. In conclusion, the results demonstrated that arthroscopic loose body removal is a more effective treatment than conservative therapy for KOA.

9.
FEBS J ; 281(12): 2713-25, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24725430

RESUMO

CCCTC-binding factor (CTCF), a highly conserved zinc finger protein, is a master organizer of genome spatial organization and has multiple functions in gene regulation. Mounting evidence indicates that CTCF regulates the imprinted genes Igf2 and H19 by organizing chromatin at the Igf2/H19 locus, although the mechanism by which CTCF carries out this function is not fully understood. By yeast two-hybrid screening, we identified vigilin, a multi-KH-domain protein, as a new partner of CTCF. Subsequent coimmunoprecipitation and glutathione S-transferase pulldown experiments confirmed that vigilin interacts with CTCF. Moreover, vigilin is present at several known CTCF target sites, such as the promoter regions of c-myc and BRCA1, the locus control region of ß-globin, and several regions within the Igf2/H19 locus. In vivo depletion of vigilin did not affect CTCF binding; however, knockdown of CTCF reduced vigilin binding to the H19 imprinting control region. Furthermore, ectopic expression of vigilin significantly downregulated Igf2 and upregulated H19, whereas depletion of vigilin upregulated Igf2 and downregulated H19, in HepG2, CNE1 and HeLa cells. These results reveal the functional relevance of vigilin and CTCF, and show that the CTCF-vigilin complex contributes to regulation of Igf2/H19.


Assuntos
Impressão Genômica , Fator de Crescimento Insulin-Like II/genética , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/metabolismo , Sequência de Bases , Fator de Ligação a CCCTC , Linhagem Celular Tumoral , Primers do DNA , Regulação da Expressão Gênica , Humanos , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas do Sistema de Duplo-Híbrido
10.
FEBS Lett ; 588(9): 1549-55, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24561205

RESUMO

CCCTC-binding factor (CTCF) has been implicated in numerous aspects of chromosome biology, and vigilin, a multi-KH-domain protein, participates in heterochromatin formation and chromosome segregation. We previously showed that CTCF interacts with vigilin. Here, we show that human vigilin, but not CTCF, colocalizes with HP1α on heterochromatic satellite 2 and ß-satellite repeats. CTCF up-regulates the transcription of satellite 2, while vigilin down-regulates it. Vigilin depletion or CTCF overexpression reduces the binding of HP1α on the satellite 2 locus. Furthermore, overexpression of CTCF resists the loading of vigilin onto the satellite 2 locus. Thus CTCF may regulate vigilin behavior and thus indirectly influence the binding of HP1α to the satellite 2 locus.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , DNA Satélite/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/fisiologia , Fator de Ligação a CCCTC , Homólogo 5 da Proteína Cromobox , Células HEK293 , Células HeLa , Heterocromatina/metabolismo , Humanos , Células MCF-7 , Ligação Proteica , Transporte Proteico , Transcrição Gênica , Ativação Transcricional
11.
Stroke ; 45(1): 290-2, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24172580

RESUMO

BACKGROUND AND PURPOSE: Deferoxamine reduces neuronal death in a piglet model of intracerebral hemorrhage (ICH). This study examined the effect of deferoxamine on perihematomal white matter edema in piglets. METHODS: ICH was induced by an injection of autologous blood into the right frontal lobe of piglets. In the first part of study, the time course of edema formation was determined. In the second part, the effects of deferoxamine on ICH-induced white matter edema, tumor necrosis factor α, and receptor-interacting protein kinase 1 were examined. RESULTS: ICH resulted in marked brain edema and increased tumor necrosis factor α and receptor-interacting protein kinase 1 levels in white matter. Systemic treatment with deferoxamine markedly reduced white matter tumor necrosis factor α and receptor-interacting protein kinase 1 levels and attenuated white matter edema after ICH. CONCLUSIONS: Deferoxamine reduces white matter edema, tumor necrosis factor α, and receptor-interacting protein kinase 1 levels after ICH in piglets, suggesting deferoxamine is a potential effective therapeutic agent for patients with ICH.


Assuntos
Encéfalo/patologia , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/patologia , Desferroxamina/uso terapêutico , Sideróforos/uso terapêutico , Animais , Western Blotting , Água Corporal/química , Química Encefálica/efeitos dos fármacos , Edema Encefálico/tratamento farmacológico , Edema Encefálico/patologia , Hemorragia Cerebral/metabolismo , Congelamento , Ferro/metabolismo , Masculino , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Suínos , Fator de Necrose Tumoral alfa/metabolismo
12.
Int J Oncol ; 42(4): 1482-92, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23426430

RESUMO

Squamous cell carcinoma antigen (SCCA) is overexpressed in many squamous cell cancers and SCCA­derived peptide-specific CD8(+) cytotoxic T lymphocytes can display cytotoxicity against tumor cells. In the present study, we screened the SCCA amino acid sequence for potential HLA-A*0201-binding CD8(+) T­cell epitopes using two predictive computational algorithms. Seven epitope candidates were selected of which SCCA(246-254)(llpneidgl), SCCA(223-231)(sledvqakv), SCCA(328­336)(vlhkafvev) and SCCA(324­332)(vlsgvlhka) significantly stabilized HLA-A*0201 molecules on T2 cells. Both SCCA(328­336) and SCCA(324-332) induced CD8(+) IFN-γ(+) T­cell responses in HLA-A*0201-positive peripheral blood mononuclear cells as assessed by intracellular cytokine staining. Consistent with this, immunization with either SCCA(328-336) or SCCA(324­332) effectively elicited CD8(+) IFN-γ(+) T cells in HLA-A*0201 transgenic mice as visualized by IFN-γ ELISPOT assay and intracellular cytokine staining. Furthermore, CD8(+) T cells induced in vitro or in vivo by SCCA(328-336) or SCCA(324-332) demonstrated in vitro cytotoxicity against peptide-pulsed T2 cells and splenocytes, respectively. These novel SCCA­derived CD8(+) T­cell epitopes described, herein, may be potentially important components for diagnostic reagents and immunotherapeutic vaccines for the treatment of squamous cell carcinomas.


Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Antígeno HLA-A2/metabolismo , Fragmentos de Peptídeos/imunologia , Serpinas/imunologia , Sequência de Aminoácidos , Animais , Vacinas Anticâncer/imunologia , Carcinoma de Células Escamosas/imunologia , Células Cultivadas , Epitopos/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ligação Proteica , Baço/citologia
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