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1.
Small ; 20(5): e2306248, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37759392

RESUMO

The Bi0.5 Sb1.5 Te3 (BST) thin film shows great promise in harvesting low-grade heat energy due to its excellent thermoelectric performance at room temperature. In order to further enhance its thermoelectric performance, specifically the power factor and output power, new approaches are highly desirable beyond the common "composition-structure-performance" paradigm. This study introduces ferroelectric polarization engineering as a novel strategy to achieve these goals. A Pb(Zr0.52 Ti0.48 )O3 /Bi0.5 Sb1.5 Te3 (PZT/BST) hybrid film is fabricated via magnetron sputtering. Density functional theory calculations demonstrate PZT polarization's influence on charge redistribution and interlayer charge transfer at the PZT/BST interface, facilitating adjustable carrier transport behavior and power factor of the BST film. As a result, a 26.7% enhancement of the power factor, from unpolarized 12.0 to 15.2 µW cm-1 K-2 , is reached by 2 kV out-of-plane downward polarization of PZT. Furthermore, a five-leg generator constructed using this PZT/BST hybrid film exhibits a maximum output power density of 13.06 W m-2 at ΔT = 39 K, which is 20.8% higher than that of the unpolarized one (10.81 W m-2 ). The research presents a new approach to enhance thermoelectric thin films' power factor and output performance by introducing ferroelectric polarization engineering.

2.
World J Urol ; 42(1): 14, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189837

RESUMO

PURPOSE: Bladder neck contracture (BNC) is a rare but intolerant complication after transurethral surgery of prostate. The present study aims to investigate the incidence and risk factors of BNC in patients diagnosed benign prostate hyperplasia (BPH) and following transurethral resection or enucleation of the prostate (TURP/TUEP). METHODS: This retrospective study included 1008 BPH individuals who underwent transurethral surgery of the prostate between January 2017 and January 2022. Patients' demographics, medical comorbidities, urologic characteristics, perioperative parameters, and the presence of BNC were documented. Univariate and multivariate analyses were conducted to identify the risk factors. RESULTS: A total of 2% (20/1008) BPH patients developed BNC postoperatively and the median occurring time was 5.8 months. Particularly, the incidences of BNC were 4.7% and 1.3% in patients underwent Bipolar-TURP and TUEP respectively. Preoperative urinary tract infection (UTI), elevated PSA, smaller prostate volume (PV), bladder diverticulum (BD), and B-TURP were significantly associated with BNC in the univariate analysis. Further multivariate logistic regression demonstrated preoperative UTI (OR 4.04, 95% CI 2.25 to 17.42, p < 0.001), BD (OR 7.40, 95% CI 1.83 to 31.66, p < 0.001), and B-TURP (OR 3.97, 95% CI 1.55 to 10.18, p = 0.004) as independent risk factors. All BNC patients were treated with transurethral incision of the bladder neck (TUIBN) combined with local multisite injection of betamethasone. During a median follow-up of 35.8 months, 35% (7/20) of BNC patients recurred at a median time of 1.8 months. CONCLUSION: BNC was a low-frequency complication following transurethral surgery of prostate. Preoperative UTI, BD, and B-TURP were likely independent risk factors of BNC. TUIBN combined with local multisite injection of betamethasone may be promising choice for BNC treatment.


Assuntos
Contratura , Hiperplasia Prostática , Masculino , Humanos , Bexiga Urinária , Próstata , Estudos Retrospectivos , Hiperplasia Prostática/cirurgia , Contratura/epidemiologia , Contratura/etiologia , Betametasona
3.
Small ; 19(13): e2201305, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35905491

RESUMO

The bottom-up constructed artificial cells help to understand the cell working mechanism and provide the evolution clues for organisms. The energy supply and metabolism mimicry are the key issues in the field of artificial cells. Herein, an artificial cell containing cyanobacteria capable of light harvesting and carbon dioxide fixation is demonstrated to produce glucose molecules by converting light energy into chemical energy. Two downstream "metabolic" pathways starting from glucose molecules are investigated. One involves enzyme cascade reaction to produce H2 O2 (assisted by glucose oxidase) first, followed by converting Amplex red to resorufin (assisted by horseradish peroxidase). The other pathway is more biologically relevant. Glucose molecules are dehydrogenated to transfer hydrogens to nicotinamide adenine dinucleotide (NAD+ ) for the production of nicotinamide adenine dinucleotide hydride (NADH) molecules in the presence of glucose dehydrogenase. Further, NADH molecules are oxidized into NAD+ by pyruvate catalyzed by lactate dehydrogenase, meanwhile, lactate is obtained. Therefore, the cascade cycling of NADH/NAD+ is built. The artificial cells built here pave the way for investigating more complicated energy-supplied metabolism inside artificial cells.


Assuntos
Células Artificiais , Cianobactérias , NAD/química , Dióxido de Carbono , Ácido Láctico , Glucose , Cianobactérias/metabolismo , Oxirredução
4.
Cell Commun Signal ; 21(1): 134, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316948

RESUMO

BACKGROUND: Age-related macular degeneration (AMD), characterized by the degeneration of retinal pigment epithelium (RPE) and photoreceptors, is the leading cause of irreversible vision impairment among the elderly. RPE senescence is an important contributor to AMD and has become a potential target for AMD therapy. HTRA1 is one of the most significant susceptibility genes in AMD, however, the correlation between HTRA1 and RPE senescence hasn't been investigated in the pathogenesis of AMD. METHODS: Western blotting and immunohistochemistry were used to detect HTRA1 expression in WT and transgenic mice overexpressing human HTRA1 (hHTRA1-Tg mice). RT-qPCR was used to detect the SASP in hHTRA1-Tg mice and ARPE-19 cells infected with HTRA1. TEM, SA-ß-gal was used to detect the mitochondria and senescence in RPE. Retinal degeneration of mice was investigated by fundus photography, FFA, SD-OCT and ERG. The RNA-Seq dataset of ARPE-19 cells treated with adv-HTRA1 versus adv-NC were analyzed. Mitochondrial respiration and glycolytic capacity in ARPE-19 cells were measured using OCR and ECAR. Hypoxia of ARPE-19 cells was detected using EF5 Hypoxia Detection Kit. KC7F2 was used to reduce the HIF1α expression both in vitro and in vivo. RESULTS: In our study, we found that RPE senescence was facilitated in hHTRA1-Tg mice. And hHTRA1-Tg mice became more susceptible to NaIO3 in the development of oxidative stress-induced retinal degeneration. Similarly, overexpression of HTRA1 in ARPE-19 cells accelerated cellular senescence. Our RNA-seq revealed an overlap between HTRA1-induced differentially expressed genes associated with aging and those involved in mitochondrial function and hypoxia response in ARPE-19 cells. HTRA1 overexpression in ARPE-19 cells impaired mitochondrial function and augmented glycolytic capacity. Importantly, upregulation of HTRA1 remarkably activated HIF-1 signaling, shown as promoting HIF1α expression which mainly located in the nucleus. HIF1α translation inhibitor KC7F2 significantly prevented HTRA1-induced cellular senescence in ARPE-19 cells, as well as improved the visual function in hHTRA1-Tg mice treated with NaIO3. CONCLUSIONS: Our study showed elevated HTRA1 contributes to the pathogenesis of AMD by promoting cellular senescence in RPE through damaging mitochondrial function and activating HIF-1 signaling. It also pointed out that inhibition of HIF-1 signaling might serve as a potential therapeutic strategy for AMD. Video Abstract.


Assuntos
Degeneração Retiniana , Idoso , Humanos , Animais , Camundongos , Epitélio Pigmentado da Retina , Transdução de Sinais , Mitocôndrias , Núcleo Celular
5.
Perfusion ; 38(2): 305-312, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34689640

RESUMO

OBJECTIVE: Levosimendan has been demonstrated to reduce the incidence of cardiogenic shock and facilitate weaning from cardiopulmonary bypass. However, the beneficial effects of levosimendan treatment on hospital outcomes in patients receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) are uncertain. We performed a systematic review and meta-analysis to evaluate the short-term effects of levosimendan use for patients undergoing VA-ECMO. METHODS: We searched PubMed, Embase, and the Cochrane Library for English articles published from inception to July 15, 2021. Observational studies comparing levosimendan versus non- levosimendan for VA-ECMO were considered eligible for the current study. RESULTS: Nine observational studies with 1058 patients were included. In-hospital mortality was 46.3% in the levosimendan group as compared with 50.7% in the control group. Levosimendan significantly reduced in-hospital mortality in patients undergoing VA-ECMO compared with the control group (RR, 0.80; 95% CI, 0.67-0.95; p = 0.013). The incidence of weaning from VA-ECMO was 79.3% in the levosimendan group as compared with 63.4% in the control group. Levosimendan significantly increase the incidence of weaning from VA-ECMO in patients as compared with the control group (RR, 1.20; 95% CI, 1.07-1.34; p = 0.002). In the one-way sensitivity analysis for estimating the effect of each study on mortality or weaning from VA-ECMO, omission of each study did not make a significant difference. CONCLUSIONS: Our study indicates that levosimendan use significantly reduced in-hospital mortality and increase the incidence of weaning in patients undergoing VA-ECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Humanos , Simendana/uso terapêutico , Oxigenação por Membrana Extracorpórea/efeitos adversos , Choque Cardiogênico/tratamento farmacológico , Mortalidade Hospitalar , Balão Intra-Aórtico , Estudos Retrospectivos
6.
Int J Mol Sci ; 24(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37175447

RESUMO

The adhesion G-protein-coupled receptor is a seven-transmembrane receptor protein with a complex structure. Impaired GPR56 has been found to cause developmental damage to the human brain, resulting in intellectual disability and motor dysfunction. To date, studies on gpr56 deficiency in zebrafish have been limited to the nervous system, and there have been no reports of its systemic effects on juvenile fish at developmental stages. In order to explore the function of gpr56 in zebrafish, the CRISPR/Cas9 gene-editing system was used to construct a gpr56-knockout zebrafish. Subsequently, the differentially expressed genes (DEGs) at the transcriptional level between the 3 days post fertilization (dpf) homozygotes of the gpr56 mutation and the wildtype zebrafish were analyzed via RNA-seq. The results of the clustering analysis, quantitative PCR (qPCR), and in situ hybridization demonstrated that the expression of innate immunity-related genes in the mutant was disordered, and multiple genes encoding digestive enzymes of the pancreatic exocrine glands were significantly downregulated in the mutant. Motor ability tests demonstrated that the gpr56-/- zebrafish were more active, and this change was more pronounced in the presence of cold and additional stimuli. In conclusion, our results revealed the effect of gpr56 deletion on the gene expression of juvenile zebrafish and found that the gpr56 mutant was extremely active, providing an important clue for studying the mechanism of gpr56 in the development of juvenile zebrafish.


Assuntos
Transcriptoma , Peixe-Zebra , Animais , Humanos , Mutação , Receptores Acoplados a Proteínas G/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
7.
Molecules ; 28(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37375322

RESUMO

The adsorption and detachment processes of n-dodecane (C12H26) molecules were studied on silica surfaces with variable surface chemistry (Q2, Q3, Q4 environments), using molecular dynamics simulations. The area density of the silanol groups varied from 9.4 to 0 per nm2. The shrinking of the oil-water-solid contact line was a key step for the oil detachment, due to water diffusion on the three-phase contact line. The simulation results showed that oil detachment was easier and faster on a perfect Q3 silica surface which had (≡Si(OH))-type silanol groups, due to the H-bond formation between the water and silanol groups. When the surfaces contained more Q2 crystalline type which had (≡Si(OH)2)-type silanol groups, less oil detached, due to the formations of H-bonds among the silanol groups. There were no silanol groups on the Si-OH 0 surface. Water cannot diffuse on the water-oil-silica contact line, and oil cannot detach from the Q4 surface. The detachment efficiency of oil from the silica surface not only depended on the area density, but also on the types of silanol groups. The density and type of silanol groups depend on the crystal cleavage plane, particle size, roughness, and humidity.

8.
J Pineal Res ; 73(1): e12802, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35436360

RESUMO

Central serous chorioretinopathy (CSC) is a vision-threatening disease with no validated treatment and unclear pathogenesis. It is characterized by dilation and leakage of choroidal vasculature, resulting in the accumulation of subretinal fluid, and serous detachment of the neurosensory retina. Numerous studies have demonstrated that melatonin had multiple protective effects against endothelial dysfunction, vascular inflammation, and blood-retinal barrier (BRB) breakdown. However, the effect of melatonin on CSC, and its exact pathogenesis, is not well understood thus far. In this study, an experimental model was established by intravitreal injection of aldosterone in rats, which mimicked the features of CSC. Our results found that melatonin administration in advance significantly inhibited aldosterone-induced choroidal thickening and vasodilation by reducing the expression of calcium-activated potassium channel KCa2.3, and attenuated tortuosity of choroid vessels. Moreover, melatonin protected the BRB integrity and prevented the decrease in tight junction protein (ZO-1, occludin, and claudin-1) levels in the rat model induced by aldosterone. Additionally, the data also showed that intraperitoneal injection of melatonin in advance inhibited aldosterone-induced macrophage/microglia infiltration, and remarkably diminished the levels of inflammatory cytokines (interleukin-6 [IL-6], IL-1ß, and cyclooxygenase-2), chemokines (chemokine C-C motif ligand 3, and C-X-C motif ligand 1), and matrix metalloproteinases (MMP-2 and MMP-9). Luzindole, as the nonselective MT1 and MT2 antagonist, and 4-phenyl-2-propionamidotetraline, as the selective MT2 antagonist, neutralized the melatonin-induced inhibition of choroidal thickening and choroidal vasodilation, indicating that melatonin might exert the effects via binding to its receptors. Furthermore, the IL-17A/nuclear factor-κB signaling pathway was activated by intravitreal administration of aldosterone, while it was suppressed in melatonin-treated in advance rat eyes. This study indicates that melatonin could serve as a promising safe therapeutic strategy for CSC patients.


Assuntos
Coriorretinopatia Serosa Central , Melatonina , Aldosterona/uso terapêutico , Animais , Coriorretinopatia Serosa Central/induzido quimicamente , Coriorretinopatia Serosa Central/tratamento farmacológico , Corioide/irrigação sanguínea , Ligantes , Melatonina/farmacologia , Melatonina/uso terapêutico , Ratos
9.
Am J Physiol Heart Circ Physiol ; 320(4): H1634-H1645, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33635162

RESUMO

Wnt/ß-catenin signaling plays a key role in pathological cardiac remodeling in adults. The identification of a tissue-specific Wnt/ß-catenin interaction factor may provide a tissue-specific clinical targeting strategy. Drosophila Pygo encodes the core interaction factor of Wnt/ß-catenin. Two Pygo homologs (Pygo1 and Pygo2) have been identified in mammals. Different from the ubiquitous expression profile of Pygo2, Pygo1 is enriched in cardiac tissue. However, the role of Pygo1 in mammalian cardiac disease is yet to be elucidated. In this study, we found that Pygo1 was upregulated in human cardiac tissues with pathological hypertrophy. Cardiac-specific overexpression of Pygo1 in mice spontaneously led to cardiac hypertrophy accompanied by declined cardiac function, increased heart weight/body weight and heart weight/tibial length ratios, and increased cell size. The canonical ß-catenin/T-cell transcription factor 4 (TCF4) complex was abundant in Pygo1-overexpressing transgenic (Pygo1-TG) cardiac tissue, and the downstream genes of Wnt signaling, that is, Axin2, Ephb3, and c-Myc, were upregulated. A tail vein injection of ß-catenin inhibitor effectively rescued the phenotype of cardiac failure and pathological myocardial remodeling in Pygo1-TG mice. Furthermore, in vivo downregulated pygo1 during cardiac hypertrophic condition antagonized agonist-induced cardiac hypertrophy. Therefore, our study is the first to present in vivo evidence demonstrating that Pygo1 regulates pathological cardiac hypertrophy in a canonical Wnt/ß-catenin-dependent manner, which may provide new clues for tissue-specific clinical treatment via targeting this pathway.NEW & NOTEWORTHY In this study, we found that Pygo1 is associated with human pathological hypertrophy. Cardiac-specific overexpression of Pygo1 in mice spontaneously led to cardiac hypertrophy. Meanwhile, cardiac function was improved when expression of Pygo1 was interfered in hypertrophy-model mice. Our study is the first to present in vivo evidence demonstrating that Pygo1 regulates pathological cardiac hypertrophy in a canonical Wnt/ß-catenin-dependent manner, which may provide new clues for a tissue-specific clinical treatment targeting this pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Insuficiência Cardíaca/metabolismo , Hipertrofia Ventricular Esquerda/metabolismo , Miocárdio/metabolismo , Função Ventricular Esquerda , Remodelação Ventricular , Via de Sinalização Wnt , beta Catenina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteína Axina/genética , Proteína Axina/metabolismo , Modelos Animais de Doenças , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/prevenção & controle , Hipertrofia Ventricular Esquerda/induzido quimicamente , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Hipertrofia Ventricular Esquerda/patologia , Isoproterenol , Masculino , Camundongos Transgênicos , Miocárdio/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Receptor EphB3/genética , Receptor EphB3/metabolismo , Tiazolidinas/farmacologia , Fator de Transcrição 4/genética , Fator de Transcrição 4/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/antagonistas & inibidores
10.
Graefes Arch Clin Exp Ophthalmol ; 259(9): 2795-2805, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34003361

RESUMO

PURPOSE: To quantitatively evaluate the lipid layer thickness (LLT) and blinking in children with or without allergic conjunctivitis (AC), and to compare those between the different types of AC. METHODS: For this case-control study, 81 children with symptomatic AC with an average age of 9.62 ± 2.67 years were enrolled and subdivided according to the subtypes of AC, including seasonal/perennial allergic conjunctivitis group and vernal keratoconjunctivitis (VKC)/atopic keratoconjunctivitis (AKC) group. Another 82 age-matched healthy children were enrolled as control group. All subjects underwent routine eye examination and measurements of LLT, the number of incomplete or total blinking, partial blinking rate by the LipiView interferometer over a 10-s period. Other ocular surface assessment included fluorescein tear breakup time (TBUT), lower tear meniscus height, meibomian gland loss (MGL), meibum expressibility and quality. RESULTS: Pediatric patients with AC had significant thinner LLT, shorter TBUT, decreased total blinking but increased partial blinking rate, especially in those with VKC/AKC (all P < 0.05). A significant deterioration of meibomian gland parameters was observed in AC group when compared with control subjects, demonstrated by severe upper and lower MGL, lid margin abnormalities, decreased meibum expressibility, and abnormal meibum quality, all of which were worse in the severe type of AC (all P < 0.05). Thinner LLT was significantly correlated with decreased TBUT (ß = 3.666, P < 0.001) and severity of upper MGL (ß = - 7.701, P = 0.002). CONCLUSION: Decreased LLT and blinking disorders in pediatric patients with AC may contribute to lipid layer deficiency in the long run, which should be considered and appropriately diagnosed for a more precise treatment.


Assuntos
Conjuntivite Alérgica , Síndromes do Olho Seco , Piscadela , Estudos de Casos e Controles , Criança , Conjuntivite Alérgica/diagnóstico , Humanos , Interferometria , Lipídeos , Glândulas Tarsais/diagnóstico por imagem , Lágrimas
11.
BMC Genomics ; 21(1): 823, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228535

RESUMO

BACKGROUND: Current single cell analysis methods annotate cell types at cluster-level rather than ideally at single cell level. Multiple exchangeable clustering methods and many tunable parameters have a substantial impact on the clustering outcome, often leading to incorrect cluster-level annotation or multiple runs of subsequent clustering steps. To address these limitations, methods based on well-annotated reference atlas has been proposed. However, these methods are currently not robust enough to handle datasets with different noise levels or from different platforms. RESULTS: Here, we present gCAnno, a graph-based Cell type Annotation method. First, gCAnno constructs cell type-gene bipartite graph and adopts graph embedding to obtain cell type specific genes. Then, naïve Bayes (gCAnno-Bayes) and SVM (gCAnno-SVM) classifiers are built for annotation. We compared the performance of gCAnno to other state-of-art methods on multiple single cell datasets, either with various noise levels or from different platforms. The results showed that gCAnno outperforms other state-of-art methods with higher accuracy and robustness. CONCLUSIONS: gCAnno is a robust and accurate cell type annotation tool for single cell RNA analysis. The source code of gCAnno is publicly available at https://github.com/xjtu-omics/gCAnno .


Assuntos
Algoritmos , Análise de Célula Única , Teorema de Bayes , Análise por Conglomerados , Análise de Sequência de RNA
12.
J Pineal Res ; 69(1): e12660, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32323368

RESUMO

Choroidal neovascularization (CNV) is an important characteristic of advanced wet age-related macular degeneration (AMD) and leads to severe visual impairment among elderly patients. Previous studies have demonstrated that melatonin induces several biological effects related to antioxidation, anti-inflammation, and anti-angiogenesis. However, the role of melatonin in CNV, and its underlying mechanisms, has not been investigated thus far. In this study, we found that melatonin administration significantly reduced the scale and volume of CNV lesions, suppressed vascular leakage, and inhibited the capacity of vascular proliferation in the laser-induced mouse CNV model. Additionally, the results also show that the melatonin-treated retinal microglia in the laser-induced mice exhibited enhanced expression of M1-type markers, such as iNOS, CCL-3, CCL-5, and TNF-α, as well as decreased production of M2-type markers, such as Arg-1, Fizz-1, IL-10, YM-1, and CD206, indicating that melatonin switched the macrophage/microglia polarization from pro-angiogenic M2 phenotype to anti-angiogenic M1 phenotype. Furthermore, the RhoA/ROCK signaling pathway was activated during CNV formation, yet was suppressed after an intraperitoneal injection of melatonin. In conclusion, melatonin attenuated CNV, reduced vascular leakage, and inhibited vascular proliferation by switching the macrophage/microglia polarization from M2 phenotype to M1 phenotype via inhibition of RhoA/ROCK signaling pathway in CNV. This suggests that melatonin could be a novel agent for the treatment of AMD.


Assuntos
Neovascularização de Coroide/metabolismo , Macrófagos/metabolismo , Melatonina/metabolismo , Microglia/metabolismo , Transdução de Sinais , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Neovascularização de Coroide/patologia , Macrófagos/patologia , Camundongos , Microglia/patologia
13.
Nanotechnology ; 31(47): 475501, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32886652

RESUMO

Carbonized polymer dots (CPDs), as a novel fluorescent material, have broad application prospects in the fields of bio-imaging, bio-sensors, disease diagnosis and photovoltaic devices due to their low cost, low toxicity, easy modification and little environmental impact. In this paper, folic acid (FA) modified CPDs (FA-CPDs) are synthesized from p-Phenylenediamine (p-PD) and FA molecules using a traditional one pot hydrothermal reaction in order to detect cancer cells containing a folate receptor (FR). The synthesized FA-CPDs were characterized by transmission electron microscopy, Fourier transfrom infrared spectroscopy, x-ray photoelectron spectroscopy, x-ray diffraction, UV-vis and fluorescence techniques. The red fluorescence emission is realized by doping phosphorus atoms into the carbonized polymer. Upon excitation at 513 nm, the maximum emission wavelength of FA-CPDs aqueous solution was obtained at 613 nm. Moreover, the as-prepared FA-CPDs exhibit excellent excitation-independent behavior and good stability with high quantum yield (QY) at about 30.6%. The binding of FA-CPDs with FRs on cancer cells produces target recognition and enters the cells through endocytosis. Additionally, it is worth noting that FA-CPDs have good biocompatibility and imaging in HeLa cells has been successfully achieved. Therefore, our FA-CPDs have potential applications as biocompatibility probes for cancer diagnosis and treatment.


Assuntos
Corantes Fluorescentes/química , Receptores de Folato com Âncoras de GPI/análise , Ácido Fólico/química , Neoplasias/diagnóstico por imagem , Polímeros/química , Pontos Quânticos/química , Carbono/química , Células HeLa , Humanos , Microscopia Confocal/métodos , Imagem Óptica/métodos
14.
J Cell Mol Med ; 23(10): 6578-6594, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31449345

RESUMO

Quaking homolog (QKI) is a member of the RNA-binding signal transduction and activator of proteins family. Previous studies showed that QKI possesses the tumour suppressor activity in human cancers by interacting with the 3'-untraslated region (3'-UTR) of various gene transcripts via the STAR domain. This study first assessed the association of QKI-6 expression with clinicopathological and survival data from bladder cancer patients and then investigated the underlying molecular mechanisms. Bladder cancer tissues (n = 223) were subjected to immunohistochemistry, and tumour cell lines and nude mice were used for different in vitro and in vivo assays following QKI-6 overexpression or knockdown. QKI-6 down-regulation was associated with advanced tumour TNM stages and poor patient overall survival. QKI-6 overexpression inhibited bladder cancer cell growth and invasion capacity, but induced tumour cell apoptosis and cell cycle arrest. Furthermore, ectopic expression of QKI-6 reduced tumour xenograft growth and expression of proliferation markers, Ki67 and PCNA. However, knockdown of QKI-6 expression had opposite effects in vitro and in vivo. QKI-6 inhibited expression of E2 transcription factor 3 (E2F3) by directly binding to the E2F3 3'-UTR, whereas E2F3 induced QKI-6 transcription by binding to the QKI-6 promoter in negative feedback mechanism. QKI-6 expression also suppressed activity and expression of nuclear factor-κB (NF-κB) signalling proteins in vitro, implying a novel multilevel regulatory network downstream of QKI-6. In conclusion, QKI-6 down-regulation contributes to bladder cancer development and progression.


Assuntos
Fator de Transcrição E2F3/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , NF-kappa B/metabolismo , Proteínas de Ligação a RNA/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Regiões 3' não Traduzidas , Animais , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Fator de Transcrição E2F3/genética , Feminino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , NF-kappa B/antagonistas & inibidores , Estadiamento de Neoplasias , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas de Ligação a RNA/genética , Transdução de Sinais/genética , Transplante Heterólogo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
15.
Nanotechnology ; 30(47): 475701, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31430734

RESUMO

In this work, we first report Au nanoclusters/porous silica particles nanocomposites as fluorescence enhanced sensors for selective and sensitive detection of Cu (II). As red-emitting GSH-protected Au nanoclusters (Au NCs) were self-assemble into porous silica particles (PSPs) after ultrasonic treatment. As a result, the Au NCs can be immobilized in the nano-channels of PSPs, which leads to the observation of an immobilized induced emission enhancement phenomenon. The photoluminscence (PL) intensity of the nanocomposites can enhance dozens of times compared with Au NCs. As a result, we obtain a novel PL enhanced sensor of Au NCs/PSPs nanocomposites with excellent PL properties. The as-prepared Au NCs/PSPs nanocomposites show good water-solubility, high stability, low toxicity, and exhibit a high PL quenching for reliable, sensitive and selective detection of Cu2+. The limit of detection can reach as low as 1 ppb. What is more, the Au NCs/PSPs nanocomposites also show sensitive detection of Cu2+ in living cells. These properties provide the Au NCs/PSPs nanocomposites with promising PL sensors for Cu2+ detection in various environmental and biological systems.


Assuntos
Cobre/química , Ouro/química , Nanocompostos/química , Dióxido de Silício/química , Animais , Linhagem Celular , Sobrevivência Celular , Corantes Fluorescentes/química , Humanos , Nanocompostos/ultraestrutura , Espectroscopia Fotoeletrônica , Porosidade
16.
J Neurosci ; 37(18): 4692-4704, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28389473

RESUMO

ST2, a member of the interleukin (IL) 1 receptor family, and its ligand IL-33 play critical roles in immune regulation and inflammatory responses. This study explores the roles of endogenous IL-33/ST2 signaling in ischemic brain injury and elucidates the underlying mechanisms of action. The expression of IL-33 rapidly increased in oligodendrocytes and astrocytes after 60 min transient middle cerebral artery occlusion (tMCAO). ST2 receptor deficiency exacerbated brain infarction 3 d after tMCAO as well as distal permanent MCAO. ST2 deficiency also aggravated neurological deficits up to 7 d after tMCAO. Conversely, intracerebroventricular infusions of IL-33 after tMCAO attenuated brain infarction. Flow cytometry analyses demonstrated high levels of ST2 expression on microglia, and this expression was dramatically enhanced after tMCAO. The absence of ST2 enhanced the expression of M1 polarization markers on microglia/macrophages, and impaired the expression of M2 polarization markers after tMCAO. In vitro studies on various types of cultures and coculture systems confirmed that IL-33/ST2 signaling potentiated expression of IL-10 and other M2 genes in primary microglia. The activation of ST2 on microglia led to a protective phenotype that enhanced neuronal survival against oxygen glucose deprivation. Further in vitro studies revealed that IL-33-activated microglia released IL-10, and that this was critical for their neuroprotective effects. Similarly, intracerebroventricular infusions of IL-33 into IL-10 knock-out mice failed to provide neuroprotection against tMCAO in vivo These results shed new light on the IL-33/ST2 axis as an immune regulatory mechanism that serves as a natural brake on the progression of ischemic brain injury.SIGNIFICANCE STATEMENT This is the first study to identify the function of interleukin (IL) 33/ST2 signaling in poststroke microglial responses and neuroprotection against ischemia. Using two models of ischemic stroke, we demonstrate here that ST2 deficiency shifted microglia/macrophages toward a M1-like phenotype, thereby expanding brain infarcts and exacerbating long-term behavioral deficits after stroke. Using stroke models and various in vitro culture and coculture systems, we further characterized a previously undefined mechanism whereby IL-33/ST2 engagement stimulates the production of IL-10 from microglia, which, in turn, enhances neuronal survival upon ischemic challenge. These results shed light on endogenous IL-33/ST2 signaling as a potential immune regulatory mechanism that serves to promote beneficial microglial responses and mitigate ischemic brain injury after stroke.


Assuntos
Lesões Encefálicas/imunologia , Isquemia Encefálica/imunologia , Encéfalo/imunologia , Proteína 1 Semelhante a Receptor de Interleucina-1/imunologia , Interleucina-33/imunologia , Microglia/imunologia , Animais , Encéfalo/patologia , Lesões Encefálicas/patologia , Isquemia Encefálica/patologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/patologia
17.
J Pineal Res ; 64(4): e12473, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29411894

RESUMO

Retinopathy of prematurity (ROP) is a retinopathy characterized by retinal neovascularization (RNV) occurring in preterm infants treated with high concentrations of oxygen and may lead to blindness in severe cases. Currently, anti-VEGF therapy is a major treatment for ROP, but it is costly and may cause serious complications. The previous study has demonstrated that melatonin exerted neuroprotective effect against retinal ganglion cell death induced by hypoxia in neonatal rats. However, whether melatonin is anti-angiogenic and neuroglial protective in the progression of ROP remains unknown. Thus, this study was to investigate the effect of melatonin on RNV and neuroglia in the retina of oxygen-induced retinopathy (OIR) mice. The results showed a reduction in retinal vascular leakage in OIR mice after melatonin treatment. Besides, the size of retinal neovascular and avascular areas, the number of preretinal neovascular cell nuclei, and the number of proliferative vascular endothelial cells within the neovascular area were significantly decreased in mice treated with melatonin. After oxygen-induced injury, the density of astrocytes was decreased, accompanied by morphologic and functional changes of astrocytes. Besides, retinal microglia were also activated. Meanwhile, the levels of inflammatory factors were elevated. However, these pathologic processes were all hindered by melatonin treatment. Furthermore, HIF-1α-VEGF pathway was activated in the retina of OIR mice, yet was suppressed in melatonin-treated OIR mice retinas. In conclusion, melatonin prevented pathologic neovascularization, protected neuroglial cells, and exerts anti-inflammation effect via inhibition of HIF-1α-VEGF pathway in OIR retinas, suggesting that melatonin could be a promising therapeutic agent for ROP.


Assuntos
Melatonina/farmacologia , Neuroglia/efeitos dos fármacos , Neovascularização Retiniana/patologia , Retinopatia da Prematuridade/patologia , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Retiniana/metabolismo , Retinopatia da Prematuridade/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Inflamm Res ; 65(1): 81-93, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26547789

RESUMO

OBJECTIVE: In the present study, we investigated the effects of Magnolol on the retinal neovascularization (RNV) and local glial cells in an oxygen-induced retinopathy (OIR) model and explored their molecular mechanisms. MATERIALS AND METHODS: Neonatal C57BL/6J mice were subjected to 75% O2 ± 5% from postnatal day (P) 7 to P12 and subsequently returned to room air. Mice were injected with 25 mg/kg Magnolol intraperitoneally once a day from P12 to P17, then retinas were harvested and flat-mounted to assess the retinal vessels, astrocytes and microglia. To clarify the molecular mechanisms of Magnolol, we observed the level of inflammatory cytokines such as interleukin (IL)-1ß, IL-6, monocyte chemoattractant protein-1, tumor necrosis factor-α, and analyzed the hypoxia-inducible factor (HIF)-1α/vascular endothelial growth factor (VEGF) pathway in OIR mice. RESULTS: Intraperitoneal administration of Magnolol resulted in significant reduction of RNV without retinal toxicity or perturbation of developmental retinal angiogenesis. In addition, Magnolol preserved the astrocyte morphology and diminished the activation of microglia. Moreover, Magnolol down regulated the expression of inflammatory cytokines and inactivated the HIF-1α/VEGF pathway. CONCLUSIONS: These results indicated that Magnolol might have potential for the treatment of pathological retinal angiogenesis and glial dysfunctions via anti-inflammation and inhibition of HIF-1α/VEGF pathway.


Assuntos
Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Oxigênio/toxicidade , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/prevenção & controle , Animais , Animais Recém-Nascidos , Astrócitos/efeitos dos fármacos , Citocinas/biossíntese , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Doenças Retinianas/patologia , Neovascularização Retiniana/induzido quimicamente , Neovascularização Retiniana/prevenção & controle , Vasos Retinianos/patologia
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 33(1): 57-60, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-26829735

RESUMO

OBJECTIVE: To identify potential mutation in a Chinese family affected with Charcot-Marie-Tooth disease(CMT). METHODS: Clinical data of the family was collected, and genomic DNA was extracted from peripheral blood samples of the family members. Seventy-two candidate genes of the proband were captured and sequenced by targeted next-generation sequencing, and the results were confirmed by Sanger sequencing. The protein structure was predicted with PyMOL-1 software. RESULTS: A homozygous missense mutation c.1894G>A(p.E632K) was identified in the exon 11 of the SH3TC2 gene in the proband. Heterozygous c.1894G>A mutation was also detected in the proband's father, mother and daughter, but not in the healthy family members and 300 normal controls. Retrieval of the NCBI, HGMD and 1000 genome databases has verified the c.1894G>A to be as a novel mutation. Computer simulation has suggested that the mutation has altered the 3D structure of the SH3TC2 protein. CONCLUSION: The proband was diagnosed as CMT4C, for which the underlying gene was SH3TC2. This finding has expanded the spectrum of SH3TC2 mutation in association with CMT4C.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Mutação de Sentido Incorreto , Proteínas/genética , Adulto , Idoso , Sequência de Bases , Análise Mutacional de DNA , Éxons , Feminino , Heterozigoto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Adulto Jovem
20.
Yi Chuan ; 37(6): 501-9, 2015 06.
Artigo em Zh | MEDLINE | ID: mdl-26351045

RESUMO

The Charcot-Marie-Tooth disease (CMT) is one of the most common human inherited peripheral neuropathies. The most common pattern of inheritance is autosomal dominant, with less often occurrence autosomal recessive and X-linked dominant/recessive inheritance. CMT is generally divided into three forms: demyelinating forms (CMT1), axonal forms (CMT2) and intermediate forms (DI-CMT). The autosomal recessive form (AR-CMT1 or CMT4) is accompanied by progressive distal muscle weakness and atrophy of the limbs, pes cavus and claw-like hands. In addition, CMT4 is also characterized by early onset, rapid progression, and varying degrees of sensory loss and spinal deformities (e.g. scoliosis). Recently, 11 subtypes of CMT4 have been identified. Some of these subtypes were clear in pathogenic mechanisms, some had founder mutation, but some still had limited clinical description and mutation analysis. In this review, we summarize the latest research progresses of CMT4, including genotypes and phenotypes, pathogenic mechanisms and mouse models.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Animais , Doença de Charcot-Marie-Tooth/classificação , Modelos Animais de Doenças , Genótipo , Humanos , Camundongos , Fenótipo
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