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1.
Artigo em Inglês | MEDLINE | ID: mdl-36799430

RESUMO

Per and polyfluoroalkyl substances (PFASs) have attracted major global concerns because some of them are environmentally persistent, bioaccumulative, and toxic. Perfluoroalkyl acids (PFAAs) have been well-characterized in water, soil, and sediment; however, fluorotelomer alcohols and perfluoroalkane sulfonamido substances have been overlooked. In this study, concentrations of three fluorotelomer alcohols and four perfluoroalkane sulfonamido substances were determined in the air at nine locations representing urban, rural-urban transect, and urban areas in the Pearl River Delta region, China to investigate their seasonal and spatial distributions and potential sources. At least two of the targeted PFASs were detected in all air samples in the Pearl River Delta region, with concentrations ranging from 371 pg/sampler to 18700 pg/sampler. Fluorotelomer alcohols were dominant compounds (contributing 46% to the ∑7PFAS concentration on average) in the atmosphere in the Pearl River Delta region. The total concentrations of the seven targeted PFASs were significantly higher in summer than in other seasons in urban areas. PFAS concentrations were positively related to the population density in the Pearl River Delta region. Local diffusive emission and long range transport could be sources of the seven PFASs in the air in the Pearl River Delta region.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Fluorocarbonos/análise , China , Estações do Ano
2.
Tumour Biol ; 37(1): 177-83, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26586400

RESUMO

MicroRNAs encoded by the miR-15b/16-2 cluster act as tumor suppressors. Aberrant regulation of miR-15b in human malignant tumors is reportedly involved in cancer development, contributing to cell death, reduced proliferation, angiogenesis and metastasis resistance, metabolism reprogramming, genome instability, and tumor-associated inflammation. In this review, we summarize the mechanisms involved in regulating miR-15b expression in mammalian tumors and discuss the effects of miR-15b dysregulation on the hallmarks of cancer and highlight its role as a potentially valuable target for future cancer therapeutic strategies.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/metabolismo , Neovascularização Patológica , Animais , Linhagem Celular Tumoral , Proliferação de Células , Perfilação da Expressão Gênica , Genoma Humano , Humanos , Inflamação , Metástase Neoplásica , Neoplasias/genética
3.
Tumour Biol ; 37(6): 7657-65, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26687759

RESUMO

RNA-binding protein Lin28A is frequently over-expressed in human malignant tumors and is associated with tumor advance and poor prognosis. However, the expression pattern and functions of Lin28A in colon cancer are unknown. In this study, we detected the expression of Lin28A in colon cancer patients and tested the effect of Lin28A on the chemotherapeutic sensitivity of colon cancer cells to 5-fluorouracil (5-FU). As expected, we showed that Lin28A is up-regulated in 73.3 % of colon cancer patients. However, to our surprise, we found that oncogenic protein Lin28A-enforced expression in colon cancer cells enhanced the chemosensitivity of cancer cells to 5-FU via promoting the cell apoptosis. Further mechanisms study revealed that the effect of Lin28A increasing chemosensitivity of cancer cells is in a let-7 independent manner, but which is associated with decreasing the expression of DNA damage repair protein H2AX. Conclusively, here we reported an unexpected function of Lin28A, which may shed lights on fully understanding the physiological and pathological roles of this oncogene.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antimetabólitos Antineoplásicos/farmacologia , Apoptose/genética , Neoplasias do Colo/tratamento farmacológico , Fluoruracila/farmacologia , Proteínas de Neoplasias/fisiologia , Proteínas de Ligação a RNA/fisiologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Apoptose/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Reparo do DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Células HCT116 , Histonas/biossíntese , Histonas/genética , Humanos , Masculino , MicroRNAs/fisiologia , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , RNA Neoplásico/fisiologia , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Método Simples-Cego
4.
Int J Gynecol Cancer ; 25(4): 566-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25756403

RESUMO

Long noncoding RNAs (lncRNAs) are longer than 200-nucleotide, noncoding transcripts in length, have a variety of biological functions, and are closely associated with tumor development. Ovarian cancer, as 1 of the 3 common gynecological malignancies, is the leading cause of death in women with gynecological malignant tumor. In this study, a review of the literature found that lncRNAs H19, LSINCT5, and XIST have a close relationship to the development of ovarian cancer occurrence, growth, invasion, and metastasis, and they can promote ovarian cancer cell proliferation. Hence, in this article, the progress of above-mentioned 3 kinds of lncRNAs in ovarian cancer was reviewed and designed to help in the diagnosis, treatment, and prognosis of ovarian cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , RNA Longo não Codificante/genética , Animais , Feminino , Humanos
5.
J Cell Mol Med ; 18(9): 1712-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25164084

RESUMO

E-cadherin is a well-known mediator of cell-cell adherens junctions. However, many other functions of E-cadherin have been reported. Collectively, the available data suggest that E-cadherin may also act as a gene transcriptional regulator. Here, evidence supporting this claim is reviewed, and possible mechanisms of action are discussed. E-cadherin has been shown to modulate the activity of several notable cell signalling pathways, and given that most of these pathways in turn regulate gene expression, we proposed that E-cadherin may regulate gene transcription by affecting these pathways. Additionally, E-cadherin has been shown to accumulate in the nucleus where documentation of an E-cadherin fragment bound to DNA suggests that E-cadherin may directly regulate gene transcription. In summary, from the cell membrane to the nucleus, a role for E-cadherin in gene transcription may be emerging. Studies specifically focused on this potential role would allow for a more thorough understanding of this transmembrane glycoprotein in mediating intra- and intercellular activities.


Assuntos
Caderinas/fisiologia , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Antígenos CD , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Humanos , NF-kappa B/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transcrição Gênica , Via de Sinalização Wnt , Proteína p120 Ativadora de GTPase/metabolismo
6.
Sci Rep ; 14(1): 5105, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429304

RESUMO

The water-rich burnt rock may threaten the safe production of coal mines. Identifying the boundaries of burnt rock and the water-rich area is of great practical significance for the ensuring the safety of mining operations. Transient electromagnetic and high-density resistivity methods are commonly employed in geophysical exploration, such as for investigating the presence of groundwater or delineating boundaries of altered rocks. These methods are non-invasive and provide detailed information about subsurface conditions without the need for drilling or excavation. The Jiangjun Gobi No. 1 open-pit coal mine is situated in the Kalamaili fault zone and is characterized by a high groundwater content. In certain mining sites within the study area, the inflow of water reaches tens of thousands of cubic meters per day, which significantly impacts production and presents major risks. To accurately determine the boundaries of burnt rock and water accumulation areas in the Jiangjun Gobi No. 1 open-pit coal mine, this paper uses different geophysical prospecting methods based on the depth of the strata. The middle and deep parts are investigated using the high-resolution transient electromagnetic method, while the shallow parts are examined using the high-accuracy high-density electric method. Through analyzing the electrical characteristics of the study area, it is inferred that the low-resistivity area in the northwest represents a shallow surface water-rich region. This area extends continuously towards the northwest, is not trapped, and is supplied by surface water. The deep low-resistivity zone primarily consists of sandstone and coarse sandstone. It is inferred that the low-resistance area in the southern part of the study area is also a shallow surface water-rich region, extending towards the east and west sides, not trapped, and supplied by surface water. The deep low-resistivity zone mainly comprises a combination of sandstone, coarse sandstone, and burnt rock, with intermittent layers of mudstone and argillaceous sandstone. The boundary line of burnt rock (coal-bearing strata) is located in the south of the study area. The resistivity of burnt rock (coal-bearing strata) is higher than that of the surrounding rocks, and the resistivity of coal seams is slightly higher than that of sandstone with larger porosity. Estimating the boundaries of groundwater and altered rocks serves to prevent geological disasters and provides valuable information for mineral development and ecological protection.

7.
Huan Jing Ke Xue ; 45(6): 3459-3467, 2024 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-38897766

RESUMO

Road transport is the primary source of greenhouse gas emissions in China's transportation field. As an important means to achieve the "double carbon" goal in the transportation field, the new energy automobile industry will face a large number of power battery scrapping in the future. In order to quantitatively assess the carbon emission reduction benefits generated by the spent ternary lithium-ion battery waste recycling industry, the carbon footprint accounting model of spent ternary lithium-ion battery waste recycling and utilization was constructed from the life cycle perspective. By optimizing the power structure and transportation structure, the carbon emission reduction potential of spent ternary lithium-ion battery waste recycling was predicted and evaluated. In addition, the uncertainty analysis was conducted using the propagation of uncertainty equation to ensure the reliability and effectiveness of the carbon footprint results. The results showed that the current carbon footprint of Chinese enterprises using wet technology to recover 1 kg waste lithium batteries was -2 760.90 g (directional recycling process) and -3 752.78 g (recycling process), and the uncertainty of the carbon footprint was 16 % (directional recycling process) and 15 % (recycling process), respectively. From the analysis of carbon emission contribution, the regenerated product stage was the primary source of carbon reduction in the wet recycling and utilization of waste ternary lithium batteries, whereas the battery acquisition, disassembly, and end treatment stages were the main sources of carbon increase. Compared to optimizing the transportation structure, optimizing the power structure could effectively achieve greater carbon emission reduction potential. Under the collaborative optimization scenario, compared to that before optimization, 14 %-19 % carbon emission reduction could be achieved. Compared with native products, the directional circulation process and recycling process could achieve 9 % and 11 % emission reduction potential, respectively.

8.
Huan Jing Ke Xue ; 44(12): 6630-6642, 2023 Dec 08.
Artigo em Zh | MEDLINE | ID: mdl-38098390

RESUMO

The steel industry is one of the most carbon-intensive industries in China. To analyze the carbon emission and carbon reduction potential of the steel industry in the life cycle, a carbon emission accounting model was built from the perspective of the life cycle. Taking the year 2020 as an example, an empirical analysis was carried out to predict and evaluate the carbon reduction potential of the steel industry in the life cycle by optimizing four variables, namely, scrap usage, fossil fuel combustion, electric power carbon footprint factor, and clean transportation proportion. At the same time, sensitivity analysis was used to determine the key degree of factors affecting carbon emission reduction in the life cycle of steel. The results showed that in 2020, the total life cycle CO2 emissions of the steel industry in China was approximately 2.404 billion tons, of which the acquisition and processing of raw materials were the key links in the carbon emissions of the steel industry, accounting for more than 98% of the total life cycle CO2 emissions of the steel industry. From the analysis of CO2 emission source categories, fossil fuel savings and outsourcing power cleaning were the top priorities of carbon reduction in the steel industry. By 2025, the steel industry could achieve 20%, 6%, 5%, and 1% carbon emission reduction potential by respectively promoting low-carbon technology, optimizing the power structure, increasing the number of steel scraps, and increasing the proportion of clean transportation. The fossil fuel combustion had the most significant impact on the life cycle CO2 emissions of the steel industry, followed by the electric power carbon footprint factor and scrap steelmaking usage. With regard to low-carbon technologies in the steel industry, in the short term, the promotion of low-carbon technologies in the steel rolling process and blast furnace ironmaking process should be the main focus. Later, with the gradual increase in the proportion of electric furnace steelmaking, the promotion of low-carbon technologies in the electric furnace steelmaking process will significantly improve the carbon emission reduction potential of the steel industry throughout its life cycle.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(2): 340-3, 2011 Feb.
Artigo em Zh | MEDLINE | ID: mdl-21510376

RESUMO

By using an ultrathin 5, 6, 11, 12-tetraphenylnaphthacene (rubrene) layer deposited on the top of host materials, the influence of rubrene layer position on the electroluminescence (EL) spectra of organic light-emitting devices (OLEDs) was stud ied. When the rubrene layer is located at the interface between N,N'-diphenyl-N,N'-bis(1-naphthyl)-(1,18-biphenyl)-4,4'-di-amine (NPB) and tris(8-hydroxyquinoline) aluminum (AlQ) layer, EL luminescence of the device is nearly coming from rubrene emission. From the analysis of the EL spectra of the devices with different rubrene layer position, the solely contribution of rubrene and AlQ, respectively, to the luminescence of the devices is determined by spectra unmixing. Based on the analysis, the exciton length in AlQ layer is determined to be about 15-20 nm. The exciton transport and recombination characteristics are also discussed in this work.

10.
Pathol Res Pract ; 215(6): 152383, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30890279

RESUMO

AIM: Arginase-1 (Arg-1) metabolizes l-arginine to l-ornithine and urea. It has been documented to have a role in various malignancies. However, the relationship between Arg-1 expression and clinicopathological characteristics of colorectal cancer (CRC) patients remains to be elucidated. The present study aimed to analyze the expression and prognostic value of Arg-1 in patients with CRC. MATERIAL AND METHODS: The mRNA and protein expressions of Arg-1 in fresh colorectal cancer tissue specimens and the corresponding noncancerous tissue specimens were examined by RT-qPCR (n = 24) and western blot analysis (n = 17). Arg-1 expression levels were determined in paraffin-embedded CRC tissue specimens (n = 236) by immunohistochemistry. The associations of Arg-1 expression and clinicopathological features and clinical prognosis in 236 CRC patients were analyzed. RESULTS: The expression levels of Arg-1 were significantly higher in the CRC tissues compared with the matched noncancerous tissues, and elevated Arg-1 expression was remarkably associated with stage III-IV tumors (P = 0.007), lymph node metastasis (P = 0.019) and a plasma albumin concentration <35 g/l (P = 0.022). Kaplan-Meier analysis indicated that Arg-1 overexpression was associated with adverse prognoses for overall survival (OS) (P < 0.001) and disease-free survival (DFS) (P < 0.001) in all cases. Further analysis revealed that the patients with high Arg-1 expression had significantly shorter OS and DFS at the advanced stages (III + IV) (P = 0.032 for OS, and P = 0.012 for DFS) but not at the early stages (I + II) (P = 0.194 for OS, and P = 0.065 for DFS). Multivariate analysis revealed that Arg-1 overexpression was an independent prognostic factor for OS (P = 0.002) and DFS (P < 0.001) in patients with CRC. CONCLUSION: The data indicated that Arg-1 overexpression in CRC may be a marker that can discriminate subgroups of patients with a poor prognosis.


Assuntos
Arginase/biossíntese , Biomarcadores Tumorais/análise , Neoplasias Colorretais/patologia , Adulto , Idoso , Arginase/análise , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Regulação para Cima
11.
Sci Rep ; 7(1): 4194, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28646148

RESUMO

Drug resistance, which is closely correlated with an imbalance in apoptosis, endows colorectal cancer (CRC) with enhanced progression capacity irrespective of the treatment with therapeutics. We report that miR-15b-5p is a tumor suppressor whose level is globally decreased in CRC cells and tissues. Over-expression of miR-15b-5p not only promoted 5-fluorouracil (5-FU)-induced cellular apoptosis but also reversed the chemoresistance of 5-FU in vitro and in vivo. As a key mediator of inflammation-induced cancer, miR-15b-5p enhances these therapeutic effects are mainly attributed to targeting of the NF-κB signaling pathway through negative regulation of NF-κB1 and one of its kinase complexes IKK-α. miR-15b-5p mediates NF-ĸB regulation by targeting the anti-apoptosis protein XIAP in vitro. Together, these results establish an axis of miR-15b-mediated apoptosis regulation, which reverses chemoresistance and suppresses CRC progression. These findings suggest that miR-15b-5p may be a potential agent for CRC treatment, particularly for 5-FU-resistant CRC.


Assuntos
Apoptose/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Fluoruracila/uso terapêutico , MicroRNAs/genética , NF-kappa B/metabolismo , Transdução de Sinais , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Quinase I-kappa B/metabolismo , Camundongos Nus , MicroRNAs/metabolismo , Modelos Biológicos
13.
J Environ Sci (China) ; 148: 650-664, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095197

RESUMO

China is the most important steel producer in the world, and its steel industry is one of the most carbon-intensive industries in China. Consequently, research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals. We constructed a carbon dioxide (CO2) emission model for China's iron and steel industry from a life cycle perspective, conducted an empirical analysis based on data from 2019, and calculated the CO2 emissions of the industry throughout its life cycle. Key emission reduction factors were identified using sensitivity analysis. The results demonstrated that the CO2 emission intensity of the steel industry was 2.33 ton CO2/ton, and the production and manufacturing stages were the main sources of CO2 emissions, accounting for 89.84% of the total steel life-cycle emissions. Notably, fossil fuel combustion had the highest sensitivity to steel CO2 emissions, with a sensitivity coefficient of 0.68, reducing the amount of fossil fuel combustion by 20% and carbon emissions by 13.60%. The sensitivities of power structure optimization and scrap consumption were similar, while that of the transportation structure adjustment was the lowest, with a sensitivity coefficient of less than 0.1. Given the current strategic goals of peak carbon and carbon neutrality, it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies, increase the ratio of scrap steel to steelmaking, and build a new power system.


Assuntos
Dióxido de Carbono , Pegada de Carbono , Aço , China , Dióxido de Carbono/análise , Poluentes Atmosféricos/análise , Metalurgia , Monitoramento Ambiental , Indústrias , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/prevenção & controle
14.
Oncol Rep ; 31(4): 1839-45, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24573322

RESUMO

Recent studies show that long intergenic noncoding RNA-p21 (lincRNA-p21) is aberrantly expressed in several types of cancer, including colorectal cancer (CRC), one of the most common cancers in the world. Radiotherapy is considered as a standard preoperative treatment approach to reduce local recurrence for local advanced rectal cancer. However, a considerable number of rectal cancers are resistant to radiotherapy. In the present study, we evaluated the role of lincRNA­p21 in radiotherapy for CRC and detected the possible molecular mechanism. By expression profile analysis, we demonstrated that lincRNA-p21 decreases in CRC cell lines and tissue samples, which contributes to the elevation of ß-catenin in CRC. We further showed that lincRNA­p21 increases following X-ray treatment, and enforced expression of the lincRNA enhances the sensitivity of radiotherapy for CRC by promoting cell apoptosis. Suppression of the ß-catenin signaling pathway and elevation of the pro-apoptosis gene Noxa expression may help explain the role of lincRNA-p21 in CRC radiotherapy. The present study not only deepens our understanding of the mechanism of radiotherapy for CRC, but it also provides a potential target for CRC radiotherapy.


Assuntos
Neoplasias Colorretais/genética , RNA Longo não Codificante/genética , Tolerância a Radiação/genética , Via de Sinalização Wnt/genética , Apoptose/genética , Western Blotting , Linhagem Celular Tumoral , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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