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1.
Opt Lett ; 49(13): 3697-3700, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950245

RESUMO

In this paper, the Fourier spectrum of an image in microsphere-assisted microscopy (MAM) and the wavenumber decomposition of the Poynting vector of the dipole model are compared for the first time to study the super-resolution performance within several wavelengths in MAM. Firstly, an experiment using microsphere-assisted microscopy is performed, and the fast Fourier transformation (FFT) spectra of the images along the distance are studied. Then the Poynting vector in the point dipole field is theoretically investigated based on the spectral decomposition of dyadic Green's function. Our study finds that the result of decomposition of the Poynting vector corresponds with the propagation results of components with different transverse wavenumbers kρ in an experiment. Even when kρ reaches 1.7k0, the waves can still arrive outside one wavelength. Our work is the first effort (to our knowledge) to associate the Fourier spectrum and the decomposition of the Poynting vector together, and it may contribute to the quantitative exploration of super-resolution performance in MAM in the future.

2.
Int J Mol Sci ; 25(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38673993

RESUMO

Cucumber (Cucumis sativus L.) is a globally prevalent and extensively cultivated vegetable whose yield is significantly influenced by various abiotic stresses, including drought, heat, and salinity. Transcription factors, such as zinc finger-homeodomain proteins (ZHDs), a plant-specific subgroup of Homeobox, play a crucial regulatory role in stress resistance. In this study, we identified 13 CsZHDs distributed across all six cucumber chromosomes except chromosome 7. Phylogenetic analysis classified these genes into five clades (ZHDI-IV and MIF) with different gene structures but similar conserved motifs. Collinearity analysis revealed that members of clades ZHD III, IV, and MIF experienced amplification through segmental duplication events. Additionally, a closer evolutionary relationship was observed between the ZHDs in Cucumis sativus (C. sativus) and Arabidopsis thaliana (A. thaliana) compared to Oryza sativa (O. sativa). Quantitative real-time PCR (qRT-PCR) analysis demonstrated the general expression of CsZHD genes across all tissues, with notable expression in leaf and flower buds. Moreover, most of the CsZHDs, particularly CsZHD9-11, exhibited varying responses to drought, heat, and salt stresses. Virus-induced gene silencing (VIGS) experiments highlighted the potential functions of CsZHD9 and CsZHD10, suggesting their positive regulation of stomatal movement and responsiveness to drought stress. In summary, these findings provide a valuable resource for future analysis of potential mechanisms underlying CsZHD genes in response to stresses.


Assuntos
Cucumis sativus , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Cucumis sativus/genética , Cucumis sativus/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Dedos de Zinco/genética , Secas , Cromossomos de Plantas/genética , Perfilação da Expressão Gênica
3.
Ann Surg Oncol ; 30(13): 8231-8243, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37755566

RESUMO

OBJECTIVE: We aimed to develop and validate a radiomics nomogram and determine the value of radiomic features from lymph nodes (LNs) for predicting pathological complete response (pCR) to neoadjuvant chemoradiotherapy (NCRT) in patients with locally advanced esophageal squamous cell carcinoma (ESCC). METHODS: In this multicenter retrospective study, eligible participants who had undergone NCRT followed by radical esophagectomy were consecutively recruited. Three radiomics models (modelT, modelLN, and modelTLN) based on tumor and LN features, alone and combined, were developed in the training cohort. The radiomics nomogram was developed by incorporating the prediction value of the radiomics model and clinicoradiological risk factors using multivariate logistic regression, and was evaluated using the receiver operating characteristic curve, validated in two external validation cohorts. RESULTS: Between October 2011 and December 2018, 116 patients were included in the training cohort. Between June 2015 and October 2020, 51 and 27 patients from two independent hospitals were included in validation cohorts 1 and 2, respectively. The radiomics modelTLN performed better than the radiomics modelT for predicting pCR. The radiomics nomogram incorporating the predictive value of the radiomics modelTLN and heterogeneous after NCRT outperformed the clinicoradiological model, with an area under the curve (95% confidence interval) of 0.833 (0.765-0.894) versus 0.764 (0.686-0.833) [p = 0.088, DeLong test], 0.824 (0.718-0.909) versus 0.692 (0.554-0.809) [p = 0.012], and 0.902 (0.794-0.984) versus 0.696 (0.526-0.857) [p = 0.024] in all three cohorts. CONCLUSIONS: Radiomic features from LNs could provide additional value for predicting pCR in ESCC patients, and the radiomics nomogram provided an accurate prediction of pCR, which might aid treatment decision.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Nomogramas , Estudos Retrospectivos , Terapia Neoadjuvante , Fator de Crescimento Transformador beta
4.
Opt Express ; 31(5): 8641-8649, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859975

RESUMO

We present for the first time a surface plasmon-enhanced dark-field microsphere-assisted microscopy in imaging both low-contrast dielectric objects and metallic ones. We demonstrate, using an Al patch array as the substrate, the resolution and contrast in imaging low-contrast dielectric objects are improved compared to that of the metal plate substrate and a glass slide in dark-field microscopy (DFM). 365-nm-diameter hexagonally arranged SiO nanodots assembled on the three substrates can be resolved, with the contrast varied from 0.23 to 0.96, and the 300-nm-diameter hexagonally close-packed polystyrene nanoparticles can only be discerned on the Al patch array substrate. The resolution can be further improved by using the dark-field microsphere-assisted microscopy, and an Al nanodot array with a nanodot diameter of ∼65 nm and a center-to-center spacing of 125 nm can be just resolved, which cannot be distinguished in a conventional DFM. The focusing effect of the microsphere, as well as the excitation of the surface plasmons, provides evanescent illumination with enhanced local electric field (E-field) on an object. The enhanced local E-field acts as a near-field excitation source to enhance the scattering of the object, resulting in the improvement of imaging resolution.

5.
Opt Lett ; 48(7): 1858-1861, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221784

RESUMO

Here we find that a fully immersed low refractive index SiO2 microsphere (or a microcylinder, a yeast cell) can clearly distinguish a sample with sub-diffraction features in dark-field illumination mode. The resolvable area of the sample by microsphere-assisted microscopy (MAM) is composed of two regions. One region locates below the microsphere, and a virtual image of this part of the sample is formed by the microsphere first and then the virtual image is received by the microscope. The other region is around the edge of the microsphere, and this part of the sample is directly imaged by the microscope. The simulated region of the enhanced electric field on the sample surface formed by the microsphere is consistent with the resolvable region in the experiment. Our studies show that the enhanced electric field on the sample surface generated by the fully immersed microsphere plays an important role in dark-field MAM imaging, and this finding will have a positive effect on exploring novel mechanisms in resolution improvement of MAM.

6.
Mol Biol Evol ; 38(12): 5472-5479, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34469542

RESUMO

Bitter taste receptors serve as a vital component in the defense system against toxin intake by animals, and the family of genes encoding these receptors has been demonstrated, usually by family size variance, to correlate with dietary preference. However, few systematic studies of specific Tas2R to unveil their functional evolution have been conducted. Here, we surveyed Tas2R16 across all major clades of primates and reported a rare case of a convergent change to increase sensitivity to ß-glucopyranosides in human and a New World monkey, the white-faced saki. Combining analyses at multiple levels, we demonstrate that a parallel amino acid substitution (K172N) shared by these two species is responsible for this functional convergence of Tas2R16. Considering the specialized feeding preference of the white-faced saki, the K172N change likely played an important adaptive role in its early evolution to avoid potentially toxic cyanogenic glycosides, as suggested for the human TAS2R16 gene.


Assuntos
Platirrinos , Paladar , Substituição de Aminoácidos , Animais , Glucosídeos , Humanos , Platirrinos/genética , Platirrinos/metabolismo , Receptores Acoplados a Proteínas G/genética , Paladar/genética
7.
New Phytol ; 236(4): 1471-1486, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36068958

RESUMO

Fusarium wilt disease, caused by Fusarium oxysporum f. sp. cucumerinum (Foc), leads to widespread yield loss and quality decline in cucumber. However, the molecular mechanisms underlying Foc resistance remain poorly understood. We report the mapping and functional characterisation of CsChi23, encoding a cucumber class I chitinase with antifungal properties. We assessed sequence variations at CsChi23 and the associated defence response against Foc. We functionally characterised CsChi23 using transgenic assay and expression analysis. The mechanism regulating CsChi23 expression was assessed by genetic and molecular approaches. CsChi23 was induced by Foc infection, which led to rapid upregulation in resistant cucumber lines. Overexpressing CsChi23 enhanced fusarium wilt resistance and reduced fungal biomass accumulation, whereas silencing CsChi23 causes loss of resistance. CsHB15, a homeodomain leucine zipper (HD-Zip) III transcription factor, was found to bind to the CsChi23 promoter region and activate its expression. Furthermore, silencing of CsHB15 reduces CsChi23 expression. A single-nucleotide polymorphism variation -400 bp upstream of CsChi23 abolished the HD-Zip III binding site in a susceptible cucumber line. Collectively, our study indicates that CsChi23 is sufficient to enhance fusarium wilt resistance and reveals a novel function of an HD-Zip III transcription factor in regulating chitinase expression in cucumber defence against fusarium wilt.


Assuntos
Quitinases , Cucumis sativus , Fusarium , Antifúngicos , Quitinases/genética , Cucumis sativus/microbiologia , Fusarium/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética
8.
Appl Opt ; 61(8): E8-E13, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35297868

RESUMO

We fabricate both triangularly and circularly shaped Au, Ag, and Cr nanoparticle arrays and observe the imaging properties of these plasmonic nanostructures by BaTiO3 glass (BTG) microsphere-assisted microscopy. We experimentally find that the resolution of triangularly shaped Ag nanoparticle arrays is higher than that of Au and Cr ones, and a gap resolution of ∼λ/7.7 is demonstrated for the circularly shaped Au, Ag, and Cr nanostructures. Numerical simulations show that when a fully immersed BTG microsphere is dispersed on the surface of a plasmonic nanostructure sample, an enhanced electric field is generated in the vicinity of the sample, especially at the gap of the microsphere and the sample, due to the focusing effect of the microsphere and the excitation of localized surface plasmon resonance in the plasmonic nanostructure. The enhanced electric field in Ag nanostructures is significantly stronger than that in Au and Cr ones. Besides, the microsphere collects, amplifies, and propagates the enhanced near-field information to the far field, resulting in the improvement of imaging resolution.

9.
Phytother Res ; 36(12): 4587-4603, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35916377

RESUMO

Andrographolide(ADE) has been demonstrated to inhibit tumor growth through direct cytotoxicity on tumor cells. However, its potential activity on tumor microenvironment (TME) remains unclear. Tumor-associated macrophages (TAMs), composed mainly of M2 macrophages, are the key cells that create an immunosuppressive TME by secretion of cytokines, thus enhancing tumor progression. Re-polarized subpopulations of macrophages may represent vital new therapeutic alternatives. Our previous studies showed that ADE possessed anti-metastasis and anoikis-sensitization effects. Here, we demonstrated that ADE significantly suppressed M2-like polarization and enhanced M1-like polarization of macrophages. Moreover, ADE inhibited the migration of M2 and tube formation in HUVECs under M2 stimulation. In vivo studies showed that ADE restrained the growth of MDA-MB-231 and HCC1806 human breast tumor xenografts and 4T-1 mammary gland tumors through TAMs. Wnt5a/ß-catenin pathway and MMPs were particularly associated with ADE's regulatory mechanisms to M2 according to RNA-seq and bioinformatics analysis. Moreover, western blot also verified the expressions of these proteins were declined with ADE exposure. Among the cytokines released by M2, PDGF-AA and CCL2 were reduced. Our current findings for the first time elucidated that ADE could modulate macrophage polarization and function through Wnt5a signaling pathway, thereby playing its role in inhibition of triple-negative breast cancer.


Assuntos
Neoplasias da Mama , Diterpenos , Via de Sinalização Wnt , Feminino , Humanos , beta Catenina , Neoplasias da Mama/tratamento farmacológico , Microambiente Tumoral , Macrófagos Associados a Tumor , Diterpenos/farmacologia , Células Endoteliais da Veia Umbilical Humana , Células MDA-MB-231 , Animais
10.
J Cell Mol Med ; 25(2): 686-700, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33225580

RESUMO

Adoptive immunotherapy is a new potential method of tumour therapy, among which anti-CD19 chimeric antigen receptor T-cell therapy (CAR-T cell), is a typical treatment agent for haematological malignancies. Previous clinical trials showed that the quality and phenotype of CAR-T cells expanded ex vivo would seriously affect the tumour treatment efficacy. Although magnetic beads are currently widely used to expand CAR-T cells, the optimal expansion steps and methods have not been completely established. In this study, the differences between CAR-T cells expanded with anti-CD3/CD28 mAb-coated beads and those expanded with cell-based aAPCs expressing CD19/CD64/CD86/CD137L/mIL-15 counter-receptors were compared. The results showed that the number of CD19-specific CAR-T cells with a 4-1BB and CD28 co-stimulatory domain was much greater with stimulation by aAPCs than that with beads. In addition, the expression of memory marker CD45RO was higher, whereas expression of exhausted molecules was lower in CAR-T cells expanded with aAPCs comparing with the beads. Both CAR-T cells showed significant targeted tumoricidal effects. The CAR-T cells stimulated with aAPCs secreted apoptosis-related cytokines. Moreover, they also possessed marked anti-tumour effect on NAMALWA xenograft mouse model. The present findings provided evidence on the safety and advantage of two expansion methods for CAR-T cells genetically modified by piggyBac transposon system.


Assuntos
Antígenos CD19/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Animais , Western Blotting , Antígenos CD8/metabolismo , Linhagem Celular Tumoral , Eletroporação , Citometria de Fluxo , Humanos , Imunoterapia Adotiva/métodos , Células K562 , Masculino , Camundongos , Camundongos SCID , Plasmídeos/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Mol Recognit ; 34(4): e2881, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33137847

RESUMO

Transforming growth factor-ß1 (TGF-ß1) signaling pathway has been implicated in the fibroblast activation of hypertrophic scarring (HS). Previously, we proposed a new biotherapeutic strategy to combat HS by disrupting the intermolecular interaction of TGF-ß1 with its cognate type-II receptor (TßR-II). Here, we further demonstrate that the binding site of TGF-ß1 to TßR-II is not overlapped with the conformational wrist epitope and linear knuckle epitope that are traditionally recognized as the functional binding sites of bone morphogenetic protein-2 (BMP-2) to its type-II receptor (BMPR-II), which can thus be regarded as a new functional site we called elbow epitope. Structural, energetic, and dynamic investigations reveal that the elbow epitope consists of two sequentially discontinuous, spatially vicinal segments Loop30-34 and Turn90-95 ; they cannot work effectively to independently interact with TßR-II. Rational redesign of the epitope is performed using an integrated in silio-in vitro method based on crystal and modeled structure data. In the procedure, the two epitope segments are split from the interface of TGF-ß1-TßR-II complex and then connected with each other in a head-to-tail manner by adding a flexible poly-(Gly)n linker between them, thus resulting in a series of combined peptides. We found that the peptide affinity reaches maximum at n = 2, which shares a consistent binding mode with the elbow epitope at native complex interface. The linker of either too long (n > 2) or too short (n < 2) cannot properly place the gap space between the two segments, thus impairing the binding compatibility of designed peptides with TßR-II active site.


Assuntos
Epitopos/química , Epitopos/metabolismo , Fragmentos de Peptídeos/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Fator de Crescimento Transformador beta1/imunologia , Sítios de Ligação , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/química , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/imunologia , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Cicatriz Hipertrófica/terapia , Polarização de Fluorescência , Humanos , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Receptor do Fator de Crescimento Transformador beta Tipo II/química , Receptor do Fator de Crescimento Transformador beta Tipo II/imunologia , Termodinâmica , Fator de Crescimento Transformador beta1/química , Fator de Crescimento Transformador beta1/metabolismo
12.
Opt Lett ; 46(13): 3099-3102, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197390

RESUMO

Observing Brownian motion of nanoscale objects through a traditional optical microscope is still a challenge. Here, we present a method to overcome this challenge by using a traditional optical microscope assisted with a removable microsphere-embedded thin film. The diffusion coefficient of individual unconstrained polystyrene (PS) nanoparticles with a diameter of 300 nm in water is calculated from their respective mean-square displacement versus time curves, and the measured diffusion coefficient shows good agreement with the theoretical Stokes-Einstein one, proving the feasibility of our method. In addition, the experimental results show that the movement of the PS nanoparticles is slowed down near a plane wall, and the diffusion coefficient is consistent with the theoretical constrained diffusion coefficient, which shows that our method can also study the constrained Brownian motion of nanoparticles constrained near a plane wall. Our research results are helpful for the application of microsphere-assisted microscopy in new fields and also provide a new method for nanoparticle tracking.

13.
Sensors (Basel) ; 20(12)2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32560462

RESUMO

We propose a low-cost passive method for monitoring long-term average levels of light-absorbing carbon air pollution in polluted indoor environments. Building on prior work, the method here estimates the change in reflectance of a passively exposed surface through analysis of digital images. To determine reproducibility and limits of detection, we tested low-cost passive samplers with exposure to kerosene smoke in the laboratory and to environmental pollution in 20 indoor locations. Preliminary results suggest robust reproducibility (r = 0.99) and limits of detection appropriate for longer-term (~1-3 months) monitoring in households that use solid fuels. The results here suggest high precision; further testing involving "gold standard" measurements is needed to investigate accuracy.

14.
J Cell Mol Med ; 23(1): 47-58, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30394676

RESUMO

Alzheimer's disease (AD) is a complex neurodegenerative disease and the most common cause of dementia among the elderly. There has been increasing recognition of sex differences in AD prevalence, clinical manifestation, disease course and prognosis. However, there have been few studies on the molecular mechanism underlying these differences. To address this issue, we carried out global gene expression and integrative network analyses based on expression profiles (GSE84422) across 17 cortical regions of 125 individuals with AD. There were few genes that were differentially expressed across the 17 regions between the two sexes, with only four (encoding glutamate metabotropic receptor 2, oestrogen-related receptor beta, kinesin family member 26B, and aspartoacylase) that were differentially expressed in three regions. A pan-cortical brain region co-expression network analysis identified pathways and genes (eg, glycogen synthase kinase 3ß) that were significantly associated with clinical characteristics of AD (such as neurofibrillary score) in males only. Similarity analyses between region-specific networks indicated that male patients exhibited greater variability, especially in the superior parietal lobule, dorsolateral prefrontal cortex and occipital visual cortex. A network module analysis revealed an association between clinical traits and crosstalk of sex-specific modules. An examination of temporal and spatial patterns of sex differences in AD showed that molecular networks were more conserved in females than in males in different cortical regions and at different AD stages. These findings provide insight into critical molecular pathways governing sex differences in AD pathology.


Assuntos
Doença de Alzheimer/genética , Encéfalo/metabolismo , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Doença de Alzheimer/patologia , Feminino , Humanos , Masculino , Lobo Occipital/metabolismo , Córtex Pré-Frontal/metabolismo , Fatores Sexuais , Córtex Visual/metabolismo
15.
Pulm Pharmacol Ther ; 54: 77-86, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30605726

RESUMO

GYY4137, a slow-releasing hydrogen sulfide (H2S) donor, has been reported to exert anti-inflammatory activity and protect against sepsis. Heme oxygenase-1 (HO-1) is an important anti-inflammatory heat shock protein and plays a similar effect on sepsis. This study investigated the role of GYY4137 in acute lung injury (ALI) via HO-1 regulation. Lung injury was assessed in mice challenged with intratracheal lipopolysaccharide (LPS) and the mechanism of anti-inflammatory effects of GYY4137 was investigated in mice and RAW264.7 cells. GYY4137 reduced the LPS-mediated pulmonary injury and neutrophil infiltration, and inhibited the LPS-induced production of proinflammatory cytokines, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Moreover, GYY4137 suppressed the LPS-evoked NF-κB activation in RAW264.7 cells. GYY4137, not time-expired GYY4137 significantly induced HO-1 expression compared with the LPS group. The beneficial effects of GYY4137 above were reversed by the HO-1 inhibitor tin protoporphyrin (SnPP). These results suggest an anti-inflammatory effect and a therapeutic role of GYY4137 in LPS-induced ALI via HO-1 regulation.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Heme Oxigenase-1/metabolismo , Morfolinas/farmacologia , Compostos Organotiofosforados/farmacologia , Lesão Pulmonar Aguda/patologia , Animais , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Inflamação/tratamento farmacológico , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Masculino , Metaloporfirinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismo , Protoporfirinas/farmacologia , Células RAW 264.7
16.
Med Sci Monit ; 25: 2511-2519, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30951518

RESUMO

BACKGROUND It has been shown that circular RNAs (circRNAs) play a vital role in the regulation of neuronal differentiation; however, the precise role of circRNAs in human neuronal differentiation remains largely unexplored. MATERIAL AND METHODS A dual-luciferase reporter assay was carried out to confirm the targets of hsa_circ_0002468, miR-561, E2F8 (E2F transcription factor 8, a protein coding gene), and miR-561. We detected the expression of hsa_circ_0002468, miR-561, and E2F8 by using quantitative real-time polymerase chain reaction (qRT-PCR) analyses. In addition, we performed the functional experiments by using a BrdU (5-bromo-2'-deoxyuridine) assay and qRT-PCR analyses. RESULTS In this study, we showed that hsa_circ_0002468 can act as a sponge of miR-561 to regulate SH-SY5Y proliferation and differentiation. A bioinformatics analysis showed that hsa_circ_0002468 had a binding site that corresponded to miR-561, which was verified by dual-luciferase reporter assay. The expression of hsa_circ_0002468 was increased during SH-SY5Y differentiation and was inversely correlated with miR-561 expression. Using qRT-PCR analysis, we showed that hsa_circ_0002468 negatively regulated miR-561 in SH-SY5Y cells. Intriguingly, the overexpression of hsa_circ_0002468 increased SH-SY5Y differentiation and reduced SH-SY5Y proliferation; the suppression of hsa_circ_0002468 led to decreased SH-SY5Y differentiation levels and increased SH-SY5Y proliferation levels. Additionally, overexpression of miR-561 rescued the SH-SY5Y proliferation deficiency induced by hsa_circ_0002468 overexpression and abolished the SH-SY5Y differentiation promoted by hsa_circ_0002468. Furthermore, E2F8 was validated as a direct target of miR-561. CONCLUSIONS Our data suggested that hsa_circ_0002468 was a novel circRNA that regulated SH-SY5Y cell proliferation and differentiation via targeting the miR-561/E2F8 axis. Therefore, manipulating hsa_circ_0002468 in SH-SY5Y cells could be a novel strategy to develop novel interventions for the treatment of relevant neurological disorders.


Assuntos
MicroRNAs/genética , Neurônios/citologia , RNA/genética , Apoptose/genética , Diferenciação Celular/genética , Linhagem Celular , Movimento Celular/genética , Proliferação de Células/genética , Biologia Computacional/métodos , Humanos , MicroRNAs/metabolismo , Neurônios/metabolismo , RNA/metabolismo , RNA Circular , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
17.
Ophthalmic Res ; 62(3): 141-149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31112970

RESUMO

BACKGROUND: Genipin (GP) is a safe method for corneal crosslinking, even for very thin corneas. However, there have been no reports on the optimal GP concentration range to use in vivo for corneal crosslinking. OBJECTIVES: To investigate the safety of corneal crosslinking after a 24-h incubation with different concentrations of GP. METHODS: Twenty New Zealand white rabbits were divided into a phosphate-buffered saline (PBS) group, 0.2% GP crosslinking (GP-CXL) group, 0.25% GP-CXL group, and 0.3% GP-CXL group. Before and after surgery, the operated eyes of each group were characterized by confocal microscopy, and corneal buttons were excised for endothelium staining and electron microscopy. RESULTS: The keratocyte structures in each GP group appeared to be similar to those in the PBS group. Through the confocal microscopy, the changes in corneal endothelial cell density also did not significantly differ among groups. There was a significant difference in apoptosis between the 0.3% GP-CXL and PBS groups (p < 0.05) and between the 0.3% GP-CXL and 0.25% GP-CXL groups (p < 0.05), but there were no significant differences between the 0.2 and 0.25% GP-CXL groups compared to the PBS group. Transmission electron microscopy showed endothelial cell damage in the 0.3% GP-CXL group, with minimal endothelial cell damage in the other groups. CONCLUSIONS: Treatment of rabbit corneas with ≤0.25% GP resulted in minimal toxicity to keratocytes and endothelial cells, suggesting that it is a safe crosslinking agent at those concentrations.


Assuntos
Córnea/efeitos dos fármacos , Reagentes de Ligações Cruzadas/toxicidade , Iridoides/toxicidade , Fotoquimioterapia/métodos , Animais , Ceratócitos da Córnea/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Fotoquimioterapia/efeitos adversos , Coelhos
18.
Cell Physiol Biochem ; 45(5): 1818-1826, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29510389

RESUMO

BACKGROUND/AIMS: Cerebral ischemia-reperfusion (I/R) injury involves multiple independently fatal terminal pathways. CK2α/NADPH oxidase is an important signaling pathway associated with ischemia-reperfusion injury, and miR-125b can regulate oxidative stress-related injury. In this study, we investigated whether the effect of miR-125b in rat brain I/R injury occurs through its modulation of the CK2α/NADPH oxidase pathway. METHODS: Rats were subjected to 2 h of cerebral ischemia followed by 24 h of reperfusion to establish an I/R injury model. Neurological deficit was evaluated using a five-point score. Infarct volume was evaluated with 2, 3, 5-triphenyltetrazolium chloride (TTC) staining, and RT-PCR was used to detect expressions of miR125b and CK2α. We then examined the association between miR-125b expression and the CK2α/NADPH oxidative signaling pathway in a PC-12 cell oxygen-glucose deprivation and reoxygenation (OGD/R) injury model. Transfection with miR-125b mimics, an miR-125b inhibitor, and luciferase reporter gene plasmid was accomplished using commercial kits. In these cells, Western blots were used to detect the levels of expression of CK2α, cleaved caspase-3, NOX2, and NOX4. RT-PCR was used to detect the expressions of CK2α, miR125b, NOX2, and NOX4. We evaluated Lactate Dehydrogenase (LDH) level, NADPH oxidase activity, and caspase-3 activity using commercial kits. Mitochondrial reactive oxygen species (ROS) were measured by fluorescence microscopy. For both PC-12 cells and rat brains, histological analyses were conducted to observe morphological changes, and apoptosis was measured using a commercial kit. RESULTS: I/R rats exhibited an increase in neurological deficit score, infarct volume, and cellular apoptosis, along with miR-125b elevation and CK2α downregulation. OGD/R treatment increased PC-12 cells' injuries, cellular apoptosis, and ROS levels. These changes were associated with miR-125b elevation, CK2α downregulation and activations of NOX2 and NOX4, mimicking our in vivo findings. All of these effects were reversed by the inhibition of miR-125b, confirming a strong correlation between miR-125b activity and the CK2α/NADPH oxidase signaling pathway. CONCLUSIONS: Based on these observations, we conclude that inhibition of miR-125b protects the rat brain from I/R injury by regulating the CK2α/NADPH oxidative signaling pathway.


Assuntos
Caseína Quinase II/metabolismo , MicroRNAs/metabolismo , NADPH Oxidases/metabolismo , Animais , Antagomirs/metabolismo , Apoptose , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/genética , Caspase 3/metabolismo , Hipóxia Celular , Modelos Animais de Doenças , Regulação para Baixo , L-Lactato Desidrogenase/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/genética , Células PC12 , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão , Transdução de Sinais
19.
Biochem Biophys Res Commun ; 503(1): 94-101, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29852175

RESUMO

Paraquat (PQ) is one of the most extensively used herbicides, possessing high toxicity for humans and animals. The lung is the main target organ by the poisoning of PQ resulting in acute lung injury. Nonetheless, molecular mechanisms underlying PQ-induced lung injury remain unclear. Here, we ask if angiopoietin-like protein 2 (Angptl2), a pro-inflammatory protein, contributes to inflammation that accelerates acute lung injury. The results indicated that abundant Angptl2 expression was observed in lung tissues of PQ-treated mice. Histological analysis revealed that PQ-induced histological changes were alleviated by Angptl2 knockout (Angptl2-/-). Angptl2-/- in PQ-treated mice attenuated acute lung injury progression by reducing the number of total cells, total leukocytes, neutrophils and macrophages in bronchoalveolar lavage fluid (BALF) and reducing inflammatory response through the inactivation of nuclear factor kappa B (NF-κB) pathway. Angptl2-/- reduced oxidative stress in PQ-treated mice, as evidenced by the enhanced superoxide dismutase (SOD) activity and reduced malondialdehyde (MDA) levels in serum or lung tissue samples, which was accompanied with increased expressions of nuclear respiratory factor 2 (Nrf-2), heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO-1). PQ-induced fibrosis was also improved in Angptl2-/- mice by decreasing pulmonary transforming growth factor (TGF)-ß1 expressions. In vitro, we found that Angptl2 knockdown-suppressed inflammation, oxidative stress and fibrosis was restored by increasing NF-κB activation in PQ-incubated A549 cells; however, the results above were significantly reversed by inactivating NF-κB using its inhibitor, Bay 11-7085 or LY2409881. Therefore, Angptl2 could provide therapeutic effects on PQ-induced acute lung injury through inhibiting inflammation, oxidative stress and fibrosis by regulating NF-κB pathway.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Proteínas Semelhantes a Angiopoietina/deficiência , NF-kappa B/metabolismo , Edema Pulmonar/prevenção & controle , Células A549 , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/antagonistas & inibidores , Proteínas Semelhantes a Angiopoietina/genética , Proteínas Semelhantes a Angiopoietina/metabolismo , Animais , Técnicas de Silenciamento de Genes , Humanos , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo , Edema Pulmonar/metabolismo , Edema Pulmonar/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle , Transdução de Sinais
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