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1.
Inorg Chem ; 61(13): 5397-5404, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35312311

RESUMO

Interfacial photogenerated charge separation and transport have demonstrated great influence on photocatalytic performance. Herein, the composite photocatalysts of methylammonium lead iodide perovskite (MAPbI3) in TiO2 with a hollow multishell structure (HoMS) are designed and synthesized. The results indicate that the heterogeneous interface within the MAPbI3/Pt/TiO2-HoMS can help enhance the separation of photogenerated charges. HoMSs assembled with multiple shells can not only support large surfaces available for building a heterogeneous interface and photocatalytic reactions but also improve the light absorption capability of photocatalysts. Besides, the thin shell structure can also reduce the transmission distance of carriers so as to hinder charge recombination and improve charge utilization. As a result, samples of MAPbI3/Pt/triple-shelled TiO2 hollow structure displayed a H2 yield of 6856.2 µmol h-1 g-1 under visible light, which is greatly better than that of bare MAPbI3 (268.6 µmol h-1 g-1).

2.
Sensors (Basel) ; 22(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35336428

RESUMO

Deep learning-based image dehazing methods have made great progress, but there are still many problems such as inaccurate model parameter estimation and preserving spatial information in the U-Net-based architecture. To address these problems, we propose an image dehazing network based on the high-resolution network, called DeHRNet. The high-resolution network originally used for human pose estimation. In this paper, we make a simple yet effective modification to the network and apply it to image dehazing. We add a new stage to the original network to make it better for image dehazing. The newly added stage collects the feature map representations of all branches of the network by up-sampling to enhance the high-resolution representations instead of only taking the feature maps of the high-resolution branches, which makes the restored clean images more natural. The final experimental results show that DeHRNet achieves superior performance over existing dehazing methods in synthesized and natural hazy images.

3.
Cell Physiol Biochem ; 33(5): 1329-39, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24803022

RESUMO

BACKGROUND/AIMS: Mounting evidence has shown that aberrant expression of miRNAs correlates with human cancers, and that miRNAs can function as tumor suppressors or oncogenes. Here, we investigated the role and mechanism of miR-142-3p in human osteosarcoma. METHODS: We used quantitative real-time RT-PCR to measure the expression of miR-142-3p in human osteosarcoma cell lines and tissues. The roles of miR-142-3p in osteosarcoma development were studied using cultured HOS, MG63 and Saos-2 cells and tumor xenograft analyses in nude mice; their target genes were also investigated. RESULTS: We found that miR-142-3p was significantly downregulated in osteosarcoma cell lines and clinical specimens. Overexpression of miR-142-3p suppressed osteosarcoma cell proliferation, migration and invasion, whereas miR-142-3p knockdown increased these parameters. The xenograft mouse model also revealed the suppressive effect of miR-142-3p on tumor growth. High mobility group AT-hook 1 (HMGA1) was identified as a target of miR-142-3p. Downregulation of HMGA1 induced effects on osteosarcoma cell lines similar to those induced by miR-142-3p. In contrast, restoration of HMGA1 abrogated the effects induced by miR-142-3p up-regulation. CONCLUSION: These results indicated that miR-142-3p may function as a tumor suppressor by targeting HMGA1 in osteosarcoma.


Assuntos
Genes Supressores de Tumor , Proteína HMGA1a/genética , Proteína HMGA1a/metabolismo , MicroRNAs/metabolismo , Osteossarcoma/metabolismo , Animais , Movimento Celular , Proliferação de Células , Relação Dose-Resposta a Droga , Regulação para Baixo , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , Osteossarcoma/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Zhonghua Yi Xue Za Zhi ; 93(20): 1583-4, 2013 May 28.
Artigo em Zh | MEDLINE | ID: mdl-24028730

RESUMO

OBJECTIVE: To evaluate the feasibility and clinical results of subsequent retroperitoneoscopic surgery for patients with previous ipsilateral retroperitoneal surgery through frank incision. METHODS: A total of 10 patents were selected for subsequent laparoscopic surgery through retroperitoneal approach. Among them, there were recurrent renal cysts (n = 4) including a history of open surgery (n = 1) and retroperitoneal surgery (n = 3) and nonfunctional kidneys (n = 6) including open nephropyelopolasty (n = 3), retroperitoneoscopic nephropyelopolasty (n = 1) and retroperitoneoscopic ureterolithotomy (n = 2). The mean surgical duration was (12-85) 38.6 months. All patients underwent retroperitoneoscopy. Decortication was performed for renal cysts and nephrectomy for nonfunctional kidneys. RESULTS: All operations were successfully performed with a mean surgical duration of 97 (40-185) minutes and a mean volume of blood loss 125 (20-460) ml. Among 4 cases with intraoperative peritoneal rupture, one case had renal cyst on ventral side. After enlargement, the procedure was performed through peritoneal cavity. The mean postoperative hospital stay was 5.6 (3-9) days. Nine patients received a mean follow-up period of 21.5 (3-47) months. All symptoms were relieved without any occurrence of postoperative complications. CONCLUSION: For patients with previous ipsilateral retroperitoneal surgery, retroperitoneoscopy may be feasible for properly selected cases.


Assuntos
Laparoscopia/métodos , Procedimentos Cirúrgicos Urológicos/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nefrectomia/métodos , Reoperação , Resultado do Tratamento
5.
Redox Biol ; 54: 102383, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35797800

RESUMO

The redox homeostasis system regulates many biological processes, intracellular antioxidant production and redox signaling. However, long noncoding RNAs (lncRNAs) involved in redox regulation have rarely been reported. Herein, we reported that downregulation of MAGI2-AS3 decreased the superoxide level in Human fibroblasts (Fbs), a replicative aging model, as detected by the fluorescent probes dihydroethidium (DHE) and MitoSOX™ Red. RNA pulldown combined with mass spectrometry showed that HSPA8 is a novel interacting protein of MAGI2-AS3, which was further confirmed by photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP). Downregulation of MAGI2-AS3 decreased the hydrogen peroxide (H2O2) content by stabilizing the HSPA8 protein level via inhibiting the protesome degradation of HSPA8. Further evidence showed that MAGI2-AS3 interacted with the C-terminal domain (CTD) of HSPA8. Downregulation of MAGI2-AS3 delayed cell senescence, while this antiaging effect was abolished by HSPA8 knockdown. The underlying molecular mechanism by which MAGI2-AS3 knockdown inhibited cell senescence was mediated via suppression of the ROS/MAP2K6/p38 signaling pathway. Taken together, these findings revealed that downregulation of lncRNA MAGI2-AS3 decreased the H2O2 content and delayed cell senescence by stabilizing the HSPA8 protein level, identifying a potential antiaging application.


Assuntos
Proteínas de Choque Térmico HSC70 , MicroRNAs , RNA Longo não Codificante , Linhagem Celular Tumoral , Proliferação de Células/genética , Senescência Celular , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSC70/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , MicroRNAs/genética , RNA Longo não Codificante/genética
6.
Antioxid Redox Signal ; 34(14): 1069-1082, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33270507

RESUMO

Significance: The redox balance of cells provides a stable microenvironment for biological macromolecules to perform their physiological functions. As redox imbalance is closely related to the occurrence and development of a variety of diseases, antioxidant therapies are an attractive option. However, redox-based therapeutic strategies have not yet shown satisfactory results. To find the key reason is of great significance. Recent Advances: We emphasize the precise nature of redox regulation and elucidate the importance and necessity of precision redox strategies from three aspects: differences in redox status, differences in redox function, and differences in the effects of redox therapy. We then propose the "5R" principle of precision redox in antioxidant pharmacology: "Right species, Right place, Right time, Right level, and Right target." Critical Issues: Redox status must be considered in the context of species, time, place, level, and target. The function of a biomacromolecule and its cellular signaling role are closely dependent on redox status. Accurate evaluation of redox status and specific interventions are critical for the success of redox treatments. Precision redox is the key for antioxidant pharmacology. The precise application of antioxidants as nutritional supplements is also key to the general health of the population. Future Directions: Future studies to develop more accurate methods for detecting redox status and accurately evaluating the redox state of different physiological and pathological processes are needed. Antioxidant pharmacology should consider the "5R" principle rather than continuing to apply global nonspecific antioxidant treatments. Antioxid. Redox Signal. 34, 1069-1082.


Assuntos
Antioxidantes/uso terapêutico , Doenças Metabólicas/dietoterapia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/genética , Microambiente Celular/efeitos dos fármacos , Microambiente Celular/genética , Suplementos Nutricionais , Humanos , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Genet Test Mol Biomarkers ; 24(3): 131-137, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32109154

RESUMO

Objective: Lipoprotein-associated phospholipase A2 (LP-PLA2) is closely related to the development of atherosclerosis. The A379V gene polymorphism, located in exon 11 of the PLA2G7 gene, can affect LP-PLA2 levels and the inflammatory response. However, the association between the A379V polymorphism and formation of carotid plaques is unclear. Materials and Methods: A total of 516 ischemic stroke patients were classified according to carotid intima-media thickness as measured by ultrasound into the plaque group (n = 375, including 258 and 117 cases having vulnerable and stable plaques, respectively) and the nonplaque group (n = 141). The LP-PLA2 gene A379V polymorphism was determined by DNA sequencing, and Lp-PLA2 serum protein levels were determined simultaneously. Results: The serum Lp-PLA2 levels (p < 0.0005), CT+TT genotype frequency (odds ratio [OR]: 1.730, 95% confidence interval [CI]: 1.114-2.686, p = 0.014), and T allele frequency (OR: 1.592, 95% CI: 1.082-2.342, p = 0.018) in the plaque group were significantly higher than those in the nonplaque group. Lp-PLA2 serum levels in the vulnerable plaque subgroup were significantly higher than those in the stable plaque subgroup (p = 0.003). However, there were no significant differences in the frequency of the A379V polymorphism between the vulnerable and stable plaque subgroups. For all subjects, Lp-PLA2 serum levels for patients having a CC genotype were significantly lower than those for patients having a CT (p = 0.003), TT (p = 0.014), or CC+TT genotype (p = 0.001). Logistic regression showed that the Lp-PLA2 level was a risk factor for carotid plaque formation (OR: 1.024, 95% CI: 1.011-1.030, p = 0.001), but the A379V gene polymorphism was not (OR: 1.037, 95% CI: 0.357-3.012, p = 0.947). Conclusion: The A379V gene polymorphism might be associated with serum Lp-PLA2 levels and carotid plaque formation, but not with plaque vulnerability in a Chinese Han population. Serum Lp-PLA2 level was shown to be a risk factor for carotid plaque formation.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Aterosclerose/genética , Placa Aterosclerótica/genética , 1-Alquil-2-acetilglicerofosfocolina Esterase/metabolismo , Idoso , Idoso de 80 Anos ou mais , Alelos , Povo Asiático/genética , Espessura Intima-Media Carotídea , China , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/sangue , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Acidente Vascular Cerebral
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