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1.
Mar Environ Res ; 196: 106416, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394977

RESUMO

Soil/sediment samples of four different land types were collected from aquaculture land, farmland, industrial land and river bottom sediment in the estuary area of Dagu River. The contents of Cr, Cu, Zn, As, Cd and Pb in 0-30 cm inner surface samples were detected, and the distribution characteristics of heavy metal content in surface soil/sediment of different land use types in the estuary area were analyzed. Local accumulation index method, potential risk index evaluation method and principal component analysis method were used to analyze the pollution status and sources of heavy metals. The results showed that the heavy metal accumulation levels in soil and sediment samples in the study area were As > Cd > Cu > Pb > Zn > Cr, and the heavy metal content exceeded the soil background value in Shandong Province, but the potential risks were all in a low risk state. The main sources of Cr, Zn and As are transportation sources and natural sources, while the main sources of Cd and Pb are agricultural.


Assuntos
Monitoramento Ambiental , Metais Pesados , Rios , Estuários , Cádmio/análise , Chumbo/análise , Medição de Risco , Metais Pesados/análise , Solo , China
2.
Oncol Res ; 31(4): 515-541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415735

RESUMO

The dysregulation of exosomal microRNAs (miRNAs) plays a crucial role in the development and progression of cancer. This study investigated the role of a newly identified serum exosomal miRNA miR-4256 in gastric cancer (GC) and the underlying mechanisms. The differentially expressed miRNAs were firstly identified in serum exosomes of GC patients and healthy individuals using next-generation sequencing and bioinformatics. Next, the expression of serum exosomal miR-4256 was analyzed in GC cells and GC tissues, and the role of miR-4256 in GC was investigated by in vitro and in vivo experiments. Then, the effect of miR-4256 on its downstream target genes HDAC5/p16INK4a was studied in GC cells, and the underlying mechanisms were evaluated using dual luciferase reporter assay and Chromatin Immunoprecipitation (ChIP). Additionally, the role of the miR-4256/HDAC5/p16INK4a axis in GC was studied using in vitro and in vivo experiments. Finally, the upstream regulators SMAD2/p300 that regulate miR-4256 expression and their role in GC were explored using in vitro experiments. miR-4256 was the most significantly upregulated miRNA and was overexpressed in GC cell lines and GC tissues; in vitro and in vivo results showed that miR-4256 promoted GC growth and progression. Mechanistically, miR-4256 enhanced HDAC5 expression by targeting the promoter of the HDAC5 gene in GC cells, and then restrained the expression of p16INK4a through the epigenetic modulation of HDAC5 at the p16INK4a promoter. Furthermore, miR-4256 overexpression was positively regulated by the SMAD2/p300 complex in GC cells. Our data indicate that miR-4256 functions as an oncogene in GC via the SMAD2/miR-4256/HDAC5/p16INK4a axis, which participates in GC progression and provides novel therapeutic and prognostic biomarkers for GC.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Transdução de Sinais , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Linhagem Celular Tumoral , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Proteína Smad2/genética , Proteína Smad2/metabolismo
3.
Eye (Lond) ; 34(4): 650-656, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31455901

RESUMO

PURPOSE: To determine clinical characteristics and identify factors associated with better visual outcomes in patients who had vitrectomy for vitreous haemorrhage (VH) associated with Terson syndrome (TS). METHODS: The records of 48 patients (54 corresponding eyes) who underwent vitrectomy for VH associated with TS from January 2008 to December 2017 were retrospectively reviewed. The main outcome measure was the final postoperative visual acuity. RESULTS: At the last visit, 34 eyes (63.0%) achieved a BCVA of 0.3 or better. Eyes associated with traumatic brain injury had a better visual outcome than those with primary intracerebral haemorrhage (P = 0.042). In the primary intracerebral haemorrhage group, patients with hypertension-induced intracranial haemorrhage (IH) showed poorer final visual acuities than the ruptured intracranial aneurysm group (P = 0.023). In the delayed vitrectomy group, epiretinal membrane and peripheral retina changes were more common (P < 0.05). However, the difference in final visual acuity between the early and delayed vitrectomy groups was not significant (P = 0.69). CONCLUSION: Most of the patients obtained visual recovery after vitrectomy for TS. VH associated with ruptured intracranial aneurysm or traumatic brain injury or eyes without retinal haemorrhage are predictive of better prognosis. Although the timing of vitrectomy was not related to the final postoperative visual outcome, early vitrectomy by three months seems to suggest less epiretinal membrane formation, retinal tears, and retinal detachments.


Assuntos
Descolamento Retiniano , Hemorragia Vítrea , Humanos , Prognóstico , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Vitrectomia , Hemorragia Vítrea/etiologia , Hemorragia Vítrea/cirurgia
4.
Artif Cells Nanomed Biotechnol ; 47(1): 4257-4265, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31736361

RESUMO

Since DNA damage is a first incident occurred during a tumour attack, it is rational that histone H2A.X phosphorylation on tyrosine 39 (H2A.XY39ph) may act as a tumour-relevant factor. This study was aimed to test the authenticity of the hypothesis. Uveal melanoma MP65 cells were transfected for expression of KRas mutated. H2A.X phosphorylation and ERK1/2 was measured, and transwell experiment was performed to examine the consequents of H2A.XY39ph on MP65 cells developing and migration. Regulatory relationship between H2A.XY39ph and ERK1/2 downstream genes were measured. Moreover, whether JMJD6 and MDM2 are involved in H2A.X phosphorylation was studied. Mutation of Ras activated ERK1/2 signalling and inhibited H2A.X phosphorylation at Y39. Silence of H2A.XY39ph contributed to the regulation of MP65 cells growth, migration and transcription of ERK1/2 downstream genes, including CYR61, IGFBP3, WNT16B, NT5E, GDF15 and CARD16. The repressed H2A.X phosphorylation through Ras-ERK1/2 signalling might be through MDM2-mediated JMJD6 degradation. Our study suggested that Ras-ERK1/2 signalling inhibited H2A.X phosphorylation at Y39, which led to the uncontrolled developing and migration of uveal melanoma cells. In addition, H2A.X phosphorylation was mediated possibly through JMJD6 which could be degraded by MDM2.


Assuntos
Carcinogênese , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Melanoma/patologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais , Neoplasias Uveais/patologia , Linhagem Celular Tumoral , Ativação Enzimática , Histonas/química , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transcrição Gênica , Tirosina/metabolismo
5.
Appl Opt ; 53(11): 2477-86, 2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-24787421

RESUMO

We present a new device, the diffractive optics calibrator (DOC), for measuring etching variations of computer-generated holograms (CGHs). The intensity distribution of the far-field diffraction pattern is captured and fitted to a parametric model to obtain local etching parameters such as the duty cycle, etching depth, and grating period. The sensitivity of each etching parameter is analyzed, and design choices are provided. For the wavefront created by the CGH, the DOC is capable of measuring variations in these parameters that cause 1 nm peak-to-valley phase errors. System performance is verified by measurements from a phase shift Fizeau interferometer. This device will be used primarily for quality control of the CGHs. The measurement results can be used to evaluate the fabrication performance and guide future design. DOC is also capable of generating an induced phase error map for calibration. Such calibration is essential for measuring free-form aspheric surfaces with 1 nm root-mean-square accuracy.

6.
Appl Opt ; 52(34): 8324-31, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24513834

RESUMO

The fabrication of computer-generated holograms (CGH) by e-beam or laser-writing machine specifically requires using polygon segments to approximate the continuously smooth fringe pattern of an ideal CGH. Wavefront phase errors introduced in this process depend on the size of the polygon segments and the shape of the fringes. In this paper, we propose a method for estimating the wavefront error and its spatial frequency, allowing optimization of the polygon sizes for required measurement accuracy. This method is validated with computer simulation and direct measurements from an interferometer.

7.
Opt Express ; 20(11): 12378-92, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22714225

RESUMO

Full aperture testing of large cryogenic optical systems has been impractical due to the difficulty of operating a large collimator at cryogenic temperatures. The Thermal Sieve solves this problem by acting as a thermal barrier between an ambient temperature collimator and the cryogenic system under test. The Thermal Sieve uses a set of thermally controlled baffles with array of holes that are lined up to pass the light from the collimator without degrading the wavefront, while attenuating the thermal background by nearly 4 orders of magnitude. This paper provides the theory behind the Thermal Sieve system, evaluates the optimization for its optical and thermal performance, and presents the design and analysis for a specific system.


Assuntos
Calefação/instrumentação , Lentes , Temperatura Baixa , Desenho de Equipamento , Análise de Falha de Equipamento
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