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1.
Opt Express ; 27(20): 29082-29097, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684649

RESUMO

In this paper, the non-Markovian dynamics of an optomechanical system is analyzed by using the non-Markovian quantum state diffusion (NMQSD) method. An exact solution is obtained for the system composed of a Fabry-Pérot (F-P) cavity with two movable mirrors without the linearization of the Hamiltonian. Based on the solution, we find that the memory effect of the non-Markovian environment can be used to generate macroscopic entanglement between two mirrors. In order to achieve the maximum entanglement generation, the non-Markovian properties of the environment have to be chosen carefully depending on the properties of the system. Then, we also show that the coherence (superposition) in the initial state may produce entanglement in the evolution. At last, we show the entanglement sudden death and revival significantly depend on the strength of the memory effect, and the entanglement revival can be only observed in non-Markovian case. Our treatment, as an example, paves a way to exactly solve a large category of optomechanical systems without the linearization of the Hamiltonian.

2.
Future Med Chem ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31702381

RESUMO

Aim: CYP3A5 plays a vital role in the drug metabolism, it displays varied expression levels among individuals and is easily influenced by genetic polymorphisms and some diseases. Methodology & results: A dual function probe isobutyryl-11-keto-ß-boswellic acid (IKBA) was developed; it possessed a high selectivity toward CYP3A5 and CYP3A enzymes for its two individual metabolites, respectively. The probe has the high accuracy and wide applicability in measuring the real activity of CYP3A5. Finally, IKBA was successfully used for the evaluation of the activity of CYP3A5 and CYP3A enzymes in various bio samples. Conclusion: IKBA could serve as a useful tool for exploring the physiology and pathology functions of CYP3A5 and give some useful guidance for the rational use of clinical drugs.

3.
FASEB J ; : fj201901388R, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31585508

RESUMO

Bone is a frequent site of metastasis from breast cancer, and a desirable drug could suppress tumor growth as well as metastasis-linked bone loss. Currently, no drug is able to cure breast cancer-associated bone metastasis. In this study, we focused on statins that are known to inhibit cholesterol production and act as antitumor agents. After an initial potency screening of 7 U.S. Food and Drug Administration-approved statins, we examined pitavastatin as a drug candidate for inhibiting tumor and tumor-induced bone loss. In vitro analysis revealed that pitavastatin acted as an inhibitor of tumor progression by altering stress to the endoplasmic reticulum, down-regulating peroxisome proliferator-activated receptor γ, and reducing Snail and matrix metalloproteinase 9. In bone homeostasis, it blocked osteoclast development by suppressing transcription factors c-Fos and JunB, but stimulated osteoblast mineralization by regulating bone morphogenetic protein 2 and p53. In a mouse model, pitavastatin presented a dual role in tumor inhibition in the mammary fat pad, as well as in bone protection in the osteolytic tibia. In mass spectrometry-based analysis, volatile organic compounds (VOCs) that were linked to lipid metabolism and cholesterol synthesis were elevated in mice from the tumor-grown placebo group. Notably, pitavastatin-treated mice reduced specific VOCs that are linked to lipid metabolites in the mevalonate pathway. Collectively, the results lay a foundation for further investigation of pitavastatin's therapeutic efficacy in tumor-induced bone loss, as well as VOC-based diagnosis of tumor progression and treatment efficacy.-Wang, L., Wang, Y., Chen, A., Teli, M., Kondo, R., Jalali, A., Fan, Y., Liu, S., Zhao, X., Siegel, A., Minami, K., Agarwal, M., Li, B.-Y., Yokota, H. Pitavastatin slows tumor progression and alters urine-derived volatile organic compounds through the mevalonate pathway.

4.
Bioresour Technol ; 294: 122239, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31610491

RESUMO

This work was aimed to determine the effects of different minerals on humic acid (HA) formation. Minerals can stimulate the formation of complex compounds, however, whether they can promote the conversion of complex compounds to HA has not been verified. Four treatments were setup from chicken manure mixed with rice hull and then added biochar (BC), montmorillonite (MMT) and biochar combined with montmorillonite (BC-MMT) for composting, while the control check (CK) was composted without minerals. The results showed that HA concentration was increased by 28.09%, 40.79%, 45.39% and 38.96% during CK, BC, BC-MMT and MMT composting. However, the bacterial community was the main reason for affecting HA concentration. Network analysis showed that obligate and facultative core microbes drove HA formation, and these driving effects were affected by minerals. Therefore, the core bacterial community promoted HA formation, which provided an insightful method to improve HA production.


Assuntos
Compostagem , Animais , Carvão Vegetal , Galinhas , Substâncias Húmicas , Esterco , Minerais , Solo
5.
Molecules ; 24(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480234

RESUMO

This work presents the first example of utilization of amphiphilic block copolymer PCL-PEG-PCL as a stationary phase for capillary gas chromatographic (GC) separations. The PCL-PEG-PCL capillary column fabricated by static coating provides a high column efficiency of 3951 plates/m for n-dodecane at 120 °C. McReynolds constants and Abraham system constants were also determined in order to evaluate the polarity and possible molecular interactions of the PCL-PEG-PCL stationary phase. Its selectivity and resolving capability were investigated by using a complex mixture covering analytes of diverse types and positional, structural, and cis-/trans-isomers. Impressively, it exhibits high resolution performance for aliphatic and aromatic isomers with diverse polarity, including those critical isomers such as butanol, dichlorobenzene, dimethylnaphthalene, xylenol, dichlorobenzaldehyde, and toluidine. Moreover, it was applied for the determination of isomer impurities in real samples, suggesting its potential for practical use. The superior separation performance demonstrates the potential of PCL-PEG-PCL and related block copolymers as stationary phases in GC and other separation technologies.

6.
Eur J Public Health ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31504445

RESUMO

BACKGROUND: The study was conducted to evaluate the independent dose-response of the night sleep duration and sleep initiation time on hypertension, and to explore their combined effect with hypertension. METHODS: Participants from the Henan Rural Cohort were enrolled in this study. Information on sleep was collected using the Pittsburgh Sleep Quality Index. Hypertension was defined as systolic blood pressure/diastolic blood pressure ≥140/90 mmHg or self-reported hypertension and current use of anti-hypertensive medicines. Logistic regression and restricted cubic spline were conducted to evaluate the association of night sleep duration and sleep initiation time with hypertension. RESULTS: Of the 37 317 included participants, 12 333 suffered from hypertension. 14 474 (38.79%) were men and 22 843 (61.21%) were women, the mean age were 57.18 ± 12.10 and 55.24 ± 11.98 in men and women. Compared to reference (7-h), fully adjusted odd ratios (ORs) and 95% confidence interval (CI) of hypertension were 0.91 (0.66-1.25) in <5 h group and 1.74 (1.41-2.16) in ≥10 h among men, respectively. Fully adjusted ORs (95% CIs) for hypertension compared with reference (21:00-22:00) were 1.05 (95% CI 0.78-1.41) in the <20:00 group, 1.52 (1.25-1.85) in ≥24:00 in men. The combined effect of sleep duration and sleep initiation time on hypertension were statistically significant in the category of (≥8 h)/night and ≥24:00 (OR 1.87, 95% CI 1.07-3.25) compared to reference in fully adjusted model among men. CONCLUSIONS: Long night sleep duration and late sleep initiation time were associated with the higher odds of hypertension, and the sleep duration and sleep initiation time might cumulatively increase the prevalence of hypertension in men. CLINICAL TRIAL REGISTRATION: The Henan Rural Cohort Study has been registered at the Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). http://www.chictr.org.cn/showproj.aspx? proj=11375.

7.
World J Gastroenterol ; 25(32): 4749-4763, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31528099

RESUMO

BACKGROUND: Liver cancer is the sixth most commonly diagnosed cancer and the fourth leading cause of cancer death worldwide. Socioeconomic development, indicated by the Human Development Index (HDI), is closely interconnected with public health. But the manner in which social development and medical advances influenced liver cancer patients in the past decade is still unknown. AIM: To investigate the influence of HDI on clinical outcomes for patients with existing liver cancer from 2008 to 2018. METHODS: The HDI values were obtained from the United Nations Development Programme, the age-standardized incidence and mortality rates of liver cancer were obtained from the GLOBOCAN database to calculate the mortality-to-incidence ratio, and the estimated 5-year net survival of patients with liver cancer was provided by the CONCORD-3 program. We then explored the association of mortality-to-incidence ratio and survival with HDI, with a focus on geographic variability across countries as well as temporal heterogeneity over the past decade. RESULTS: From 2008 to 2018, the epidemiology of liver cancer had changed across countries. Liver cancer mortality-to-incidence ratios were negatively correlated and showed good fit with a modified "dose-to-inhibition response" pattern with HDI (r = -0.548, P < 0.0001 for 2018; r = -0.617, P < 0.0001 for 2008). Cancer survival was positively associated with HDI (r = 0.408, P < 0.01) and negatively associated with mortality-to-incidence ratio (r = -0.346, P < 0.05), solidly confirming the interrelation among liver cancer outcome indicators and socioeconomic factors. Notably, in the past decade, the HDI values in most countries have increased alongside a decreasing tendency of liver cancer mortality-to-incidence ratios (P < 0.0001), and survival outcomes have simultaneously improved (P < 0.001), with significant disparities across countries. CONCLUSION: Socioeconomic factors have a significant influence on cancer outcomes. HDI values have increased along with improved cancer outcomes, with significant disparities among countries.

8.
Bioresour Technol ; 294: 122132, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31526931

RESUMO

This study aims to explore the effect of Fenton pretreatment on organic fractions, enzymes activities and microbial communities during composting. In this study, rice straw was chosen to be composted after pretreatment. The results indicated that Fenton pretreatment significantly increased the degradation of organic matter and coarse fiber contents, which might be the reason that Fenton pretreatment enhanced lignocellulose-degrading enzymes activities during composting, including CMCase, FPase, xylanase, manganese peroxidase, lignin peroxidase and laccase. Additionally, Fenton pretreatment reshaped bacteria community. The key enzymes and environmental factors, which affected organic fractions degradation were identified by redundancy analysis. Furthermore, structural equation modeling and variation partitioning analysis further revealed possible mechanisms of organic fractions degradation in different treatments during composting. In summary, the combined application Fenton pretreatment and composting improved lignocellulose degradation efficiency, which provided for an effective and environment-friendly way to manage lignocellulose wastes.


Assuntos
Compostagem , Oryza , Lignina , Solo
9.
Bioresour Technol ; 294: 122153, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31550635

RESUMO

The aim of this study was to explore the conversion characteristics of neutral sugars during different lignocellulose wastes composting from rice straw (RS), leaf (L) and mushroom dreg (MD). The results showed that the changes of neutral sugars were different during different wastes composting, but the changes of various hexose or pentose were similar during composting of the same material. The diversity of bacterial community led to different conversion characteristics of neutral sugars. During RS composting, each neutral sugar was transformed by a specific group of bacteria. However, a group of bacteria could transform multiple neutral sugars during MD and L composting. Furthermore, GM/AX value was first applied to composting, which could be used to characterize the conversion of neutral sugars during composting. This will help to provide more efficient recommendations for lignocellulose wastes treatment and accelerating humic substances synthesis during composting.


Assuntos
Compostagem , Bactérias , Lignina , Solo , Açúcares
10.
Cell Death Dis ; 10(9): 665, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511499

RESUMO

Endothelial dysfunction initiates and exacerbates hypertension, atherosclerosis and other cardiovascular complications in diabetic mellitus. FGF21 is a hormone that mediates a number of beneficial effects relevant to metabolic disorders and their associated complications. Nevertheless, it remains unclear as to whether FGF21 ameliorates endothelial dysfunction. Therefore, we investigated the effect of FGF21 on endothelial function in both type 1 and type 2 diabetes. We found that FGF21 reduced hyperglycemia and ameliorated insulin resistance in type 2 diabetic mice, an effect that was totally lost in type 1 diabetic mice. However, FGF21 activated AMPKα, suppressing oxidative stress and enhancing endothelium-dependent vasorelaxation of aorta in both types, suggesting a mechanism that is independent of its glucose-lowering and insulin-sensitizing effects. In vitro, we identified a direct action of FGF21 on endothelial cells of the aorta, in which it bounds to FGF receptors to alleviate impaired endothelial function challenged with high glucose. Furthermore, the CaMKK2-AMPKα signaling pathway was activated to suppress oxidative stress. Apart from its anti-oxidative capacity, FGF21 activated eNOS to dilate the aorta via CaMKK2/AMPKα activation. Our data suggest expanded potential uses of FGF21 for the treatment of vascular diseases in diabetes.

11.
Environ Pollut ; 255(Pt 1): 113170, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31520909

RESUMO

Nitrogen (N) addition can change physicochemical properties and biogeochemical processes in soil, but whether or not these changes further affect the transport and transformation of heavy metal speciation is unknown. Here, a long-term (2004-2016) field experiment was conducted to assess the responses of different heavy metal speciation in three soil aggregate fractions to N additions in a temperate agroecosystem of North China. The organic matter turnover time was quantified based on changes in δ13C following the conversion from C3 (wheat) to C4 crop (corn). Averagely, N addition decreases and increases the heavy metal contents in bioavailable and organic bound fractions by 27.5% and 16.6%, respectively, suggesting N addition promotes the transformation of heavy metal speciation from bioavailable to organic bound, and such a promotion in a small aggregate fraction is more remarkable than that in a large aggregate fraction. The transformations of heavy metal speciation from bioavailable to organic bound in all soil aggregate fractions are largely dependent on the increments in the turnover time of organic matter. The increase in organic matter turnover time induced by N addition may inhibit the desorption of heavy metals from organic matter by prolonging the interaction time between heavy metals and organic matter and enhance the capacity of organic matter to adsorb heavy metals by increasing the humification degree and functional group. Our work can provide insights into the accumulation, migration, and transformation of heavy metals in soils in the context of increasing global soil N input from a microenvironmental perspective.

12.
Comp Biochem Physiol B Biochem Mol Biol ; 239: 110348, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31526840

RESUMO

The suppressor of cytokine signaling 3 (SOCS3) negatively regulates the responses of various immune cytokines. In this study, we identified socs3s genes of blunt snout bream. 209- and 216-aa long peptides are encoded by socs3a and socs3b genes, respectively. The socs3s mRNAs are expressed consistently during the entire process of embryonic development. Whole-mount in situ hybridization detected socs3a in the eyes and posterior somites at 12 h post fertilization (hpf), transcribed at the otic vesicle at 24 hpf, and transcribed at the eyes, brain, and otic vesicle at 36 hpf; while the socs3b mRNA was transcribed at the notochord at 12 hpf, expressed in the brain, eyes, and tailbud at 24 hpf, and detected in the brain at 36 hpf. The expression of socs3a is slightly different from that of socs3b in tissues of juvenile and adult blunt snout bream. After recombinant human growth hormone (hGH) treatment, the transcript levels of socs3s of blunt snout bream were increased in gills, spleen, kidney, and gonads. After Aerononas hydrophila infection, the mRNA levels of socs3s of blunt snout bream were significantly increased in the liver, spleen, intestine, and kidney tissues. Blunt snout bream were susceptible to various pathogenic microorganisms, we intraperitoneally injected blunt snout bream with A. hydrophila to explore the immune mechanism of socs3s. These results suggested that socs3s of blunt snout bream plays important roles in the regulation of embryonic development and tissue growth, and that socs3s may also play key roles in regulating the bacterial-induced congenital immune response. Socs3s genes has the potential to be used as targeted genes to improve the immunity against bacteria, which is conducive to the improvement of production and breeding.

13.
Gen Comp Endocrinol ; 284: 113243, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31408625

RESUMO

The suppressor of cytokine signaling 1 (SOCS1) is an essential feedback regulator extensively involved in many different cytokine signaling pathways, such as regulation of the immune system and growth of organism. However, the molecular and functional information on socs1 genes in freshwater fish is unclear. In the present paper, we identified and characterized the full-length closely related but distinct socs1 genes (socs 1a and -1b) in blunt snout bream (Megalobrama amblycephala). The bioinformatic analysis results showed that duplicated socs1s shared majority conserved motifs with other vertebrates. Both socs1a and -1b mRNAs were detected throughout embryogenesis, and gradually increase and then constantly expressed after 16 hpf. Whole-mount in situ hybridization demonstrated that socs1a and socs1b mRNAs were detected in the brain at 12hpf and 24hpf, and in the notochord and brain at 36hpf. In adult fish, the socs1a mRNA were strongly expressed in the heart, eye, kidney, spleen and gonad, but were found to be relatively low in the intestine and liver. On the other hand, the expression of socs1b mRNA was significantly high in the muscle, eye and spleen, and relatively low in the intestine, liver, skin and heart. The results of hGH treatment experiment showed that socs1a and 1b mRNAs were upregulated markedly in the kidney, muscle and liver. Overexpression of socs1s significantly inhibit the GH and JAK/STAT factor stat3 and the inhibitory effect of SOCS1s on GH may be involved in JAK-STAT signaling pathway. These results indicate that SOCS1 plays an important role in regulating growth and development.

14.
Nano Lett ; 19(9): 6547-6553, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31414823

RESUMO

In CO2 electroreduction, the critical bottleneck lies in the CO2 activation which requires high overpotentials. CO2 activation is related to both the electronic structures of catalysts and those of adsorbates, thus an ideal catalyst should match its electronic structures with those of the adsorbate. Here, we harmonized the electronic structures of the adsorbate and Mn-doped In2S3 nanosheets for efficient CO2 reduction. The introduction of Mn dopants into In2S3 nanosheets enhanced both the Faradaic efficiency (FE) for carbonaceous products and current density (j). At -0.9 V vs RHE, Mn-doped In2S3 nanosheets exhibited a remarkable FE of 92% for carbonaceous product at a high j of 20.1 mA cm-2. Mechanistic studies revealed that Mn doping enabled the harmonic overlaps between the p orbitals of O atoms and d orbitals of Mn atoms near the conduction band edge of Mn-doped In2S3 nanosheets during the activation of CO2. Due to the unique electronic structures of the coadsorbed configurations, Mn-doped In2S3 nanosheets exhibited an energy barrier for CO2 activation into HCOO* lower than that over pristine In2S3 nanosheets.

15.
Cancer Immunol Res ; 7(10): 1580-1590, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31399419

RESUMO

PD-1 (CD279)-PD-L1 (CD274) inhibitory signaling is critical for cancer immune evasion, and thus has become one of the major targets in anticancer immunotherapy. There are several studies that demonstrate the potent effects of posttranslational modifications of CD274 on immune inactivation and suppression, such as ubiquitination, phosphorylation, glycosylation, and palmitoylation. However, the regulatory mechanisms for CD274 deubiquitination are still largely unclear. Here, we identified ubiquitin-specific protease 22 (USP22) as a novel deubiquitinase of CD274. USP22 directly interacted with the C terminus of CD274, inducing its deubiquitination and stabilization. Across multiple cancer types, USP22 was highly expressed and frequently altered in liver cancer, closely correlating with poor prognosis of these patients. Genetic depletion of USP22 inhibited liver cancer growth in an immune system-dependent manner, increased tumor immunogenicity and tumor-infiltrating lymphocytes, and improved therapeutic efficacy of CD274-targeted immunotherapy and CDDP-based chemotherapy in mice. We demonstrate that targeting USP22 is a promising strategy to potentiate anticancer immunity for CD274-amplified cancer.

16.
Life Sci ; 233: 116731, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394128

RESUMO

AIMS: Multiple sclerosis (MS) is an inflammatory disease of the central nervous system characterized by widespread inflammation. LncRNA taurine-up-regulated gene 1 (TUG1) has been reported to be involved in multiple biological processes and human diseases. The aim of this study was to investigate the role of lncRNA TUG1 in MS and the underlying mechanism. MAIN METHODS: Experimental autoimmune encephalomyelitis (EAE) was induced in mice by immunization with myelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55). Lentiviral vectors encoding sh-TUG1 was constructed to silence TUG1 in MOG-EAE mice by intracerebroventricular (ICV) injection. The effect of TUG1 on inflammation in MS was evaluated by real-time PCR, Western blot, ELISA and Hematoxylin-eosin staining. To further study the mechanism of TUG1 in MS, TUG1 knockdown and miR-9-5p overexpression were performed in LPS-induced BV2 cells. KEY FINDINGS: Down-regulation of TUG1 improved mice behavior, reduced granulocyte-macrophage colony stimulating factor (GM-CSF) level, decreased the levels of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-6 and IL-17, and increased IL-10 in EAE mice. Notably, TUG1 expression was negatively correlated with miR-9-5p expression, while positively correlated with NF-κB1/p50. Knockdown of TUG1 or enforced expression of miR-9-5p inhibited LPS-induced inflammation in BV2 cells, while these effects were abolished by inhibition of miR-9-5p. We further verified that TUG1 negatively regulated miR-9-5p expression and NF-κB1/p50 is a direct target of miR-9-5p. SIGNIFICANCE: Down-regulation of TUG1 attenuates MS through inhibition of inflammation by sponging miR-9-5p via targeting NF-κB1/p50, suggesting that TUG1 is a potential therapeutic target for MS treatment.


Assuntos
Encefalomielite Autoimune Experimental/prevenção & controle , Regulação da Expressão Gênica , Inflamação/prevenção & controle , MicroRNAs/genética , Esclerose Múltipla/prevenção & controle , Subunidade p50 de NF-kappa B/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , Animais , Apoptose , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/patologia , Inflamação/induzido quimicamente , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Subunidade p50 de NF-kappa B/genética , RNA Longo não Codificante/genética , Ativação Transcricional
17.
Phys Chem Chem Phys ; 21(31): 17163-17169, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31342023

RESUMO

Two-dimensional (2D) heteromaterials with large interface contact and intimate interfacial charge transition have been considered to be an ideal model for constructing highly efficient photocatalysts. However, few studies have reported on these 2D heterojunctions. Herein, we report a series of new 2D heterojunctions comprising polyimide (PI) and perylene-3,4,9,10-tetracarboxylic dianhydride (TD). These heterojunctions, denoted as PI-TDx (where x represents the amount of TD added, i.e., x = 0.13, 0.18, 0.27, 0.54, and 1.08 g), were prepared by the solid thermal copolymerization of melamine (MA), pyromellitic dianhydride (PD), and different amounts of TD. FT-IR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy analyses were used to verify the 2D heterojunction structure. Photocatalytic experiments reveal that PI-TDx exhibit excellent and stable photocatalytic performance for the degradation of the organic dyes rhodamine B (RhB) and methyl violet (MV), as well as for the photoreduction of Cr(vi), under visible-light irradiation. Among the samples, PI-TD0.18 exhibits the best photocatalytic performance. Its activity is about 2.7 times and 7.5 times higher than that of individual PIMP (formed by MA and PD) and PIMT (formed by MA and TD) for RhB degradation, respectively. Notably, PI-TD0.18 retains a certain photocatalytic activity under light irradiation at 600 nm. The photocatalytic-mechanism study demonstrates that PI-TD0.18 has a classic type-II heterojunction. Its 2D heterojunction greatly enhances the visible-light absorption of the composites and effectively suppresses the radiation recombination of photogenerated carriers, thereby improving its charge transfer and separation abilities and providing excellent photocatalytic performance. This work may serve as an important reference for the design and construction of new highly efficient 2D organic conjugated-polymer photocatalysts.


Assuntos
Poluentes Ambientais/química , Perileno/análogos & derivados , Perileno/química , Resinas Sintéticas/química , Catálise , Cromo/química , Corantes/química , Violeta Genciana/química , Luz , Oxirredução , Processos Fotoquímicos , Rodaminas/química , Propriedades de Superfície
18.
Chem Commun (Camb) ; 55(63): 9363-9366, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31317136

RESUMO

We developed a biodegradable, oncosensitive, megamer-based delivery system for miRNA therapy. The miRNA nanotherapeutics, activatable by stepwise stimulation of acidity and reduction mimicking tumor microenvironment, efficiently improve liver-specific miR-122 expression, increasing the possibility of translational application of miR-122 therapy against liver cancer.


Assuntos
Portadores de Fármacos/química , MicroRNAs/química , Nanopartículas/química , Polietilenoglicóis/química , Animais , Linhagem Celular Tumoral , Dendrímeros/química , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , MicroRNAs/uso terapêutico , Transplante Heterólogo
19.
ACS Appl Mater Interfaces ; 11(31): 27934-27943, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31319023

RESUMO

Construction of various nanostructure g-C3N4, especially those with a tubular structure, is gaining considerable research interest because of their large specific surface area, high carrier transport efficiency, and excellent mass transfer. In this study, a novel multistage tubular g-C3N4 (TCN) has been prepared by the copolymerization of melamine formaldehyde (MF) resin with urea. With the introduction of MF resin, the electrostructure of TCN and its hydrophilicity property have been obviously ameliorated, thereby enhancing its visible-light absorption and improving the interface contact between TCN and water. Moreover, photocurrent response and electrochemical impedance spectra indicate that the special multistage tubular structure facilitates the spatial charge transfer and photogenerated carrier separation. Thus, the as-prepared TCN exhibits excellent photoactivities under visible-light irradiation. Among the samples, TCN-0.1 shows the best performance. Its hydrogen evolution rate is approximately 7505 µmol·g-1·h-1, which is 6.05 times greater than that of g-C3N4 (prepared by urea at 600 °C), and its apparent quantum efficiency is nearly 19.2% at 400 nm. In addition, TCN is also endowed with outstanding visible-light performance and durability for the degradation of tetracycline and methyl orange. This work might provide a significant inspiration for the design of new, highly efficient g-C3N4-based materials and further deepen our understanding of the preparation of tubular photocatalysts.

20.
J Med Syst ; 43(8): 283, 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31300897

RESUMO

According to diagnostic criteria, skin tumors can be divided into three categories: benign, low degree and high degree malignancy. For high degree malignant skin tumors, if not detected in time, they can do serious harm to patients' health. However, in clinical practice, identifying malignant degree requires biopsy and pathological examination which is time costly. Furthermore, in many areas, due to the severe shortage of dermatologists, it's inconvenient for patients to go to hospital for examination. Therefore, an easy to access screening method of malignant skin tumors is needed urgently. Firstly, we spend 5 years to build a dataset which includes 4,500 images of 10 kinds of skin tumors. All instances are verified pathologically thus trustworthy; Secondly, we label each instance to be either low-risk, high-risk or dangerous in which Junctional nevus, Intradermal nevus, Dermatofibroma, Lipoma and Seborrheic keratosis are low-risk, Basal cell carcinoma, Bowen's disease and Actinic keratosis are high-risk, Squamous cell carcinoma and Malignant melanoma are dangerous; Thirdly, we apply the Xception architecture to build the risk degree classifier. The area under the curve (AUC) for three risk degrees reach 0.959, 0.919 and 0.947 respectively. To further evaluate the validity of the proposed risk degree classifier, we conduct a competition with 20 professional dermatologists. The results showed the proposed classifier outperforms dermatologists. Our system is helpful to patients in preliminary screening. It can identify the patients who are at risk and alert them to go to hospital for further examination.

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