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1.
Cancer Lett ; 522: 155-163, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560228

RESUMO

Prostate cancer (PCa) is the second most common cancer in men and is a highly heritable disease that affects millions of individuals worldwide. Genome-wide association studies have to date discovered nearly 270 genetic loci harboring hundreds of single nucleotide polymorphisms (SNPs) that are associated with PCa susceptibility. In contrast, the functional characterization of the mechanisms underlying PCa risk association is still growing. Given that PCa risk-associated SNPs are highly enriched in noncoding cis-regulatory genomic regions, accumulating evidence suggests a widespread modulation of transcription factor chromatin binding and allelic enhancer activity by these noncoding SNPs, thereby dysregulating gene expression. Emerging studies have shown that a proportion of noncoding variants can modulate the formation of transcription factor complexes at enhancers and CTCF-mediated 3D genome architecture. Interestingly, DNA methylation-regulated CTCF binding could orchestrate a long-range chromatin interaction between PCa risk enhancer and causative genes. Additionally, one-causal-variant-two-risk genes or multiple-risk-variant-multiple-genes are prevalent in some PCa risk-associated loci. In this review, we will discuss the current understanding of the general principles of SNP-mediated gene regulation, experimental advances, and functional evidence supporting the mechanistic roles of several PCa genetic loci with potential clinical impact on disease prevention and treatment.

2.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2889-2899, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467710

RESUMO

Sophorae Flavescentis Radix,derived from the root of Sophora flavescens in the Leguminosae family,has been widely used in the medicine,agriculture,animal husbandry,and daily chemical industry. A pharmacophore model-based method for rapid discovery of tyrosinase inhibitors( TIs) from S. flavescens was established by molecular docking under Lipinski rules,and verified by enzyme assays. Briefly,the chemical constituent database of S. flavescens( CDSF) was established based on the previous papers. Theoptimal pharmacophore model( OPM) was constructed by DS 2019 on the basis of known active TIs. Eighty-three hits predominated by flavonoids having higher fitting scores with OPM than the positive control were screened out,and subjected to molecular docking based on the three-dimensional structure of tyrosinase crystal protein. The potential TIs such as kurarinone and nor-kurarinone were rapidly discovered from the compounds with higher docking scores than the positive control under the Lipinski rules. The results were verified by the in vitro enzyme assays. The inhibition activities of tyrosinase from non-medicinal parts of S. flavescens were also tested to explore the relationship between the inhibition activity and chemical compositions. This study is expected to provide data support for the comprehensive application and development of S. flavescens and also a new method for the rapid discovery of active substances or functional constituents in the complex systems.


Assuntos
Sophora , Animais , Flavonoides , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase , Extratos Vegetais/farmacologia , Raízes de Plantas
3.
Huan Jing Ke Xue ; 42(2): 688-698, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742863

RESUMO

A comparative analysis of phosphate occurrence and its genesis during different dispatching periods of representative level I tributaries of the Three Gorges Reservoir was conducted. For this, water quality, hydrodynamic force, and environmental data were examined for backwater areas of the Xiangxi River and Shennong River during the low-water-level period (June), storage period (September) and high-water-level period (December) in 2018. The results suggest that the mass concentration of total phosphorus (TP) in the water body of the coves of Xiangxi River and Shennong River range from 0.049 mg·L-1 to 0.168 mg·L-1 and 0.059 mg·L-1 to 0.152 mg·L-1, respectively, surpassing the 0.02 mg·L-1 threshold for algal blooms. The mass concentration of TP, DP (orthophosphate), and PP (particulate phosphorus) in the coves of the tributaries were ranked as follows:storage period > high-water-level period > low-water-level period for TP; storage period > low-water-level period > high-water-level period for DP; low-water-level period > high-water-level period > storage period for PP. Based on Pearson's correlation coefficients, TP and DP were significantly correlated as well as temperature and pH, which are the key factors influencing the phosphorus in soils and sediments in the water-level-fluctuation zone. During the low-water-level and high-water-level periods of the Three Gorges Reservoir, the TP in the coves of the tributaries mainly exists as PP, accounting for more than 75% and 60%, respectively. The flow in the coves of the tributaries slows during storage periods, meaning that settlement of PP is enhanced, changing the dominance of TP to dissolved total phosphorus (DTP).

4.
BMC Infect Dis ; 21(1): 206, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627072

RESUMO

BACKGROUND: There is limited information on the difference in epidemiology, clinical characteristics and outcomes of the initial outbreak of the coronavirus disease (COVID-19) in Wuhan (the epicenter) and Sichuan (the peripheral area) in the early phase of the COVID-19 pandemic. This study was conducted to investigate the differences in the epidemiological and clinical characteristics of patients with COVID-19 between the epicenter and peripheral areas of pandemic and thereby generate information that would be potentially helpful in formulating clinical practice recommendations to tackle the COVID-19 pandemic. METHODS: The Sichuan & Wuhan Collaboration Research Group for COVID-19 established two retrospective cohorts that separately reflect the epicenter and peripheral area during the early pandemic. The epidemiology, clinical characteristics and outcomes of patients in the two groups were compared. Multivariate regression analyses were used to estimate the adjusted odds ratios (aOR) with regard to the outcomes. RESULTS: The Wuhan (epicenter) cohort included 710 randomly selected patients, and the peripheral (Sichuan) cohort included 474 consecutive patients. A higher proportion of patients from the periphery had upper airway symptoms, whereas a lower proportion of patients in the epicenter had lower airway symptoms and comorbidities. Patients in the epicenter had a higher risk of death (aOR=7.64), intensive care unit (ICU) admission (aOR=1.66), delayed time from illness onset to hospital and ICU admission (aOR=6.29 and aOR=8.03, respectively), and prolonged duration of viral shedding (aOR=1.64). CONCLUSIONS: The worse outcomes in the epicenter could be explained by the prolonged time from illness onset to hospital and ICU admission. This could potentially have been associated with elevated systemic inflammation secondary to organ dysfunction and prolonged duration of virus shedding independent of age and comorbidities. Thus, early supportive care could achieve better clinical outcomes.


Assuntos
COVID-19/complicações , SARS-CoV-2 , Adulto , Idoso , COVID-19/virologia , China/epidemiologia , Comorbidade , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Eliminação de Partículas Virais
5.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-229781

RESUMO

SARS-CoV-2 invades human respiratory epithelial cells via an interaction between its spike RBD protein (SARS-CoV-2 S-RBD) and the host cell receptor angiotensin converting enzyme II (ACE2). Blocking this interaction provides a potent approach to preventing and controlling SARS-CoV-2 infection. In this work, the ability of {beta}-chitosan to block the binding interaction between SARS-CoV-2 S-RBD and ACE2 was investigated. The inhibitory effect of {beta}-chitosan on inflammation induced by the SARS-CoV-2 S-RBD was also studied. Native-PAGE analysis indicated that {beta}-chitosan could bind with ACE2 and the SARS-CoV-2 S-RBD and a conjugate of {beta}-chitosan and ACE2 could no longer bind with the SARS-CoV-2 S-RBD. HPLC analysis suggested that a conjugate of {beta}-chitosan and the SARS-CoV-2 S-RBD displayed high binding affinity without dissociation under high pressure (40 MPa) compared with that of {beta}-chitosan and ACE2. Furthermore, immunofluorescent staining of Vero E6 cells and lungs from hACE2 mice showed that the presence of {beta}-chitosan prevented SARS-CoV-2 S-RBD from binding to ACE2. Meanwhile, {beta}-chitosan could dramatically suppress the inflammation caused by the presence of the SARS-CoV-2 S-RBD both in vitro and vivo. Moreover, the decreased expression of ACE2 caused by {beta}-chitosan treatment was restored by addition of TAPI-1, an inhibitor of the transmembrane protease ADAM17. Our findings demonstrated that {beta}-chitosan displays an antibody-like function capable of neutralizing the SARS-CoV-2 S-RBD and effectively preventing the binding of the SARS-CoV-2 S-RBD to ACE2. Moreover, ADAM17 activation induced by {beta}-chitosan treatment can enhance the cleavage of the extracellular domain of ACE2, releasing the active ectodomain into the extracellular environment, which can prevent the binding, internalization, and degradation of ACE2 bound to the SARS-CoV-2 S-RBD and thus diminish inflammation. Our study provides an alternative avenue for preventing SARS-CoV-2 infection using {beta}-chitosan.

6.
Hum Immunol ; 81(8): 452-459, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32534760

RESUMO

Based on CD25 expression, T follicular helper cells (Tfh) could be divided into T follicular regulatory (Tfr)-like subset (CD25+CD4+CXCR5+) and CD25- Tfh subset (CD25-CD4+CXCR5+). Patients with diffuse large B cell lymphoma (DLBCL) display high level of Tfr-like cells in blood and tumor. This Tfr-like subset could suppress CD8 T cell response while promote tumor cell proliferation. In this study, we investigated the transcription factors and regulatory elements associated with Tfr-like cells in DLBCL patients. Both circulating and tumor-infiltrating Tfr-like cells presented slightly higher Blimp-1 expression and significantly higher Foxp3 expression than the CD25- Tfh subset. As the IL-2 receptor, CD25 could be moderately upregulated in stimulated CD25- Tfh cells. However, stimulated CD25- Tfh cells could not upregulate Foxp3, indicating that the distinction between Foxp3-low CD25-CXCR5+CD4+ T cells and Foxp3-high CD25+CXCR5+CD4+ T cells was not due to differences in stimulation status. Regarding cytokine production, while both Tfr-like and CD25- Tfh cells upregulated IL-21 and IL-10 during stimulation, the CD25- Tfh cells presented significantly higher IL-21 and lower IL-10 expression than the Tfr-like cells, and the TGF-ß expression was only increased in Tfr-like cells. Interestingly, IL-21 secreted from CD25- Tfh cells negatively regulated the expression of Foxp3 and IL-10 of autologous Tfr-like cells. Together, these results demonstrated that the Tfr-like and CD25- Tfh subsets of circulating Tfh cells presented different functions and should be investigated separately.


Assuntos
Fatores de Transcrição Forkhead/imunologia , Interleucinas/imunologia , Linfoma Difuso de Grandes Células B/imunologia , Células T Auxiliares Foliculares/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Citocinas/imunologia , Feminino , Humanos , Interleucina-10/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta/imunologia , Regulação para Cima/imunologia
7.
Biomed Microdevices ; 22(3): 43, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-32504225

RESUMO

This paper presents a fabrication method for glassy carbon neural electrode arrays that combines 3D printing and chemical pyrolysis technology. The carbon electrodes have excellent biological compatibility and can be used in neural signal recording. A pretreated Si wafer is used as the substrate for 3D printing, and then, stereolithography 3D printing technology is employed to print photosensitive resin into a cone shape. Next, chemical pyrolysis is applied to convert the 3D prints into glassy carbon electrodes and modify the electrochemical performance of the carbon electrodes. Finally, the glassy carbon electrodes are packed with conductive wires and PDMS. The proposed fabrication method simplifies the manufacturing process of carbon materials, and electrodes can be fabricated without the need of deep reactive ion etching (DRIE). The height of the carbon electrodes is 1.5 mm, and the exposure area of the tips is 0.78 mm2, which is convenient for the implantation procedure. The specific capacitance of the glassy carbon arrays is higher than that of a platinum electrode (9.18 mF/cm2 vs 3.32 mF/cm2, respectively), and the impedance at 1 kHz is lower (7.1 kΩ vs 8.8 kΩ). The carbon electrodes were tested in vivo, and they showed excellent performance in neural signal recording. The signal-to-noise ratio of the carbon electrodes is 50.73 ± 6.11, which is higher than that of the Pt electrode (20.15 ± 5.32) under the same testing conditions. The proposed fabrication method of glassy carbon electrodes provides a novel approach to manufacture penetrating electrodes for nerve interfaces in biomedical engineering and microelectromechanical systems.


Assuntos
Interfaces Cérebro-Computador , Carbono/química , Eletrodos Implantados , Vidro/química , Dimetilpolisiloxanos , Condutividade Elétrica , Desenho de Equipamento , Neurônios/citologia , Nylons , Impressão Tridimensional , Razão Sinal-Ruído , Silício/química
8.
Cancer Med ; 9(12): 4265-4273, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32281302

RESUMO

Researches have pointed that piplartine inhibits the proliferation of hepatocellular carcinoma (HCC) cells, however, the underlying mechanisms has not been well defined. Currently, more and more studies have pointed out that circRNAs can regulate tumor cell proliferation, involve in the tumorigenesis mechanism of various tumors. In this study, we explored whether piplartine may participate in the development of HCC through the regulation of ability of HCC cell proliferation by circRNA. Based on the chip analysis, we selected candidate circRNAs that are highly correlated with HCC. CircRNA expression in OSCC cells treated with piplartine was detected by qRT-PCR. We found that only the expression of hsa_circ_100338 (circ-100338) was observably reduced. The expression characteristics of circ-100338 in HCC cell lines were also verified by qRT-PCR. Subsequently, whether or notcirc-100338 can regulate ZEB1 via competitively binding to miR-141-3p was determined by the RIP assay and dual luciferase reporter gene assay. The effect of the circ-100338/miR-141-3p/ZEB1 axis on the proliferation of HCC cell was tested by EdU and CCK-8 assay. Results showed that circ-100338 expression was observably increased in HCC cell lines. Simultaneously, circ-100338 can regulate the expression of ZEB1by competitively binding to miR-141-3p. Moreover high expression of circ-100338 can stimulate the proliferation of HCC cells. Our current study revealed that circ-100338 played as a ceRNA in promoting the progression of HCC by sponging miR-141-3p, while piplartine can participate in the development of HCC by inhibiting the expression of circ-100338.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Piperidonas/farmacologia , RNA Circular/genética , Animais , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1350-1356, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32281347

RESUMO

To define the composition of relevant substances in Breviscapine for Injection, in order to improve the quality control of impurity, and ensure the clinical safety. The analysis and structural identification of relevant substances in different specifications and batches of Breviscapine for Injection powders were carried out by HPLC and UPLC-QTOF-MS. Three primary relevant substances, namely 5,6,7,3',4'-pentahydroxyflavone-7-O-glucuronide(3), 3,5,6,7,4'-pentahydroxyflavone-3-O-glucuronide(4) and scutellarein(10), as well as three minor impurities, namely 6-hydroxyapigenin-6-O-glucosyl-7-O-glucuronide(1), methoxylscutellarin(6) and apigenin-7-O-glucuronide(7) were structurally identified by matching retention time, UV spectra, and mass spectra with authentic compounds and MS fragmentation rules. The main relevant substances(3) and(4) were separated and purified by semi-preparative HPLC, and their structures were further confirmed by NMR data. The study defined relevant substances of Breviscapine for Injection, and provided reference for improving the quality control level of single impurity in breviscapine preparation.


Assuntos
Apigenina/análise , Medicamentos de Ervas Chinesas/normas , Flavonoides/química , Glucuronídeos/análise , Cromatografia Líquida de Alta Pressão , Injeções , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Controle de Qualidade
10.
Drug Dev Ind Pharm ; 46(4): 531-538, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32141352

RESUMO

Orodispersible films (ODFs) are promising drug delivery systems for customized medicines as it provide an alternative approach to increase consumer acceptance by advantages of rapid dissolution and administration without water. The aim of this study was to develop a platform to support the realization of tailored treatments suitable for the extemporaneous production of ODFs by semi-solid extrusion (SSE) 3D printing (3DP). Hydroxypropyl methyl cellulose (HPMC) was used as the polymer of ODFs, and levocetirizine hydrochloride was used as the model drug. The optimal formulation was HPMC:API:PS:maltitol:sucralose at a ratio of 64:10:10:15:1. Seventeen percent HPMC solution and optimal formulation were used to prepare film precursors. The impact of dynamic viscosities and fluid mechanics difference on printing applicability was discussed. The ODFs of cube designs with aimed dose of 1.25 mg, 2.5 mg, and 5 mg were printed by SSE 3DP. Good linear relationship between theoretical model volume and drug content (R2 = 0.999) and good dose accuracy indicate that 3DP is a suitable method for preparing individualized ODFs.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Derivados da Hipromelose/química , Impressão Tridimensional , Administração Oral , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Estudos de Viabilidade , Solubilidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-32148552

RESUMO

There has been an increase in morbidity and mortality related to coronary heart disease (CHD) in China in recent years. Numerous clinical experiences and studies have shown that traditional Chinese medicine (TCM) plays an important role in the prevention, treatment, and prognosis of CHD. However, the mechanism of TCM in the treatment of CHD has not yet been elucidated. The circRNA-miRNA-mRNA network consists of miRNA that is competitively bound by circRNA, and miRNA regulates the transcription level of mRNA. Through literature review, we found that the circRNA-miRNA-mRNA network acts to contribute to certain effects to CHD such as myocardial hypertrophy, myocardial fibrosis, and heart failure. TCM contains constituents that act against CHD by antiatherosclerosis and apoptosis inhibition action, cardiac and cardiomyocyte protection, and these components also promote cell growth and protection of the vascular system by regulating miRNAs. Therefore, we consider that the circRNA-miRNA-mRNA network may be a new regulatory mechanism for the effective treatment of CHD by TCM.

12.
Chem Commun (Camb) ; 55(76): 11382-11385, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31482876

RESUMO

The construction of a nano-heterojunction photoanode is an attractive strategy for accelerated charge separation. Here, α-Fe2O3 nanorod arrays (Fe2O3 NAs) top-decorated with an MIL-101 layer are achieved via the CVD method for constructing one intimate contact between two layers. The systematical analysis in time-dependent deposition shows that the photoelectric response capability can be modulated by controlling the thickness of the MIL-101 layer as a function of CVD duration. An optimized thickness of 4-6 nm MIL-101 in the Fe2O3/MIL-101 photoanode presents the best PEC performance with the IPCE of 25% and a photocurrent density of 1 mA cm-2 at 1.3 V vs. RHE, about 2.5 times higher than that of pristine Fe2O3 NAs. The exciton lifetime and the electrochemical active surface area of the composited electrode are greatly improved by 14 and 1.3 times respectively compared to that of pristine Fe2O3. The notable advancement can be attributed to the fact that the top-decorated MOF layer can promote charge separation efficiency led by the built-in electric field and form a tight interface between Fe2O3 and MIL-101 with a favorable diffusion length for holes, as well as the fact that it can reduce surface defects and provide more reaction sites.

13.
Int J Mol Sci ; 20(18)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489906

RESUMO

Effector proteins secreted by plant pathogens play important roles in promoting colonization. Blumeria effector candidate (BEC) 1019, a highly conserved metalloprotease of Blumeria graminis f. sp. hordei (Bgh), is essential for fungal haustorium formation, and silencing BEC1019 significantly reduces Bgh virulence. In this study, we found that BEC1019 homologs in B. graminis f. sp. tritici (Bgt) and Gaeumannomyces graminis var. tritici (Ggt) have complete sequence identity with those in Bgh, prompting us to investigate their functions. Transcript levels of BEC1019 were abundantly induced concomitant with haustorium formation in Bgt and necrosis development in Ggt-infected plants. BEC1019 overexpression considerably increased wheat susceptibility to Bgt and Ggt, whereas silencing this gene using host-induced gene silencing significantly enhanced wheat resistance to Bgt and Ggt, which was associated with hydrogen peroxide accumulation, cell death, and pathogenesis-related gene expression. Additionally, we found that the full and partial sequences of BEC1019 can trigger cell death in Nicotiana benthamiana leaves. These results indicate that Bgt and Ggt can utilize BEC1019 as a virulence effector to promote plant colonization, and thus these genes represent promising new targets in breeding wheat cultivars with broad-spectrum resistance.


Assuntos
Predisposição Genética para Doença , Hordeum/genética , Hordeum/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Sequência de Bases , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Fenótipo
14.
Appl Environ Microbiol ; 85(23)2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31540983

RESUMO

Genetic polymorphism and endosymbiont infection are ubiquitous in aphid populations. It has been known that the obligate symbiont Buchnera provides aphids with essential amino acids which cannot be ingested from plant sap. Buchnera often coexists with facultative endosymbionts in aphids. However, it is unclear whether the facultative endosymbionts affect the aphid's amino acid requirements from diet. In this study, we found that the facultative endosymbiont status in populations of the cotton-melon aphid Aphis gossypii was associated with aphid genotype or host plant. The infection frequency of Arsenophonus in aphids living on cotton was significantly higher than that in aphids on cucumber, and cucumber leaves contained higher titers of free amino acids than cotton leaves, especially amino acids Leu, Arg, Ile, Val, and Phe. The net reproductive rates of five aphid genotypes infected with Arsenophonus were not different on the complete-amino-acid diet, but the values were significantly different among seven Arsenophonus-free aphid genotypes. Moreover, the net reproductive rates of aphids on the amino-acid-deficient diet were significantly affected by Arsenophonus infection and aphid genotype. Arsenophonus infection decreased aphid performance on the Phe-free diet but improved performance on the Leu-free diet and did not affect the performance on the Ile-free or Val-free diet. Arsenophonus infections altered aphid requirements for amino acids that were significantly different in cotton and cucumber leaves, suggesting this endosymbiont would modulate the host specialization of this aphid.IMPORTANCE The facultative endosymbiont Arsenophonus plays an important role in regulating reproduction through son killing, enemy resistance, and the dietary breadth of its insect hosts. In this study, we found Arsenophonus could alter aphid performance on the amino-acid-deficient diets. Arsenophonus infection increased aphid requirements for the amino acid Phe, but decreased requirements for the Leu. Cotton and cucumber leaves contained drastically different titers of free amino acids Phe and Leu, and aphids living on these two plants were infected with different incidences of Arsenophonus We hypothesize that host specialization or the host plant range of aphids may be mediated by Arsenophonus.


Assuntos
Afídeos/microbiologia , Cadeia Alimentar , Gammaproteobacteria/fisiologia , Simbiose , Aminoácidos/deficiência , Animais , Afídeos/crescimento & desenvolvimento , Cucumis sativus , Gossypium , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia
15.
Environ Int ; 130: 104898, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31228786

RESUMO

A unique heterostructure is developed based on a 3D photoactive semiconductor and a 0D Cu2O QDs for superb photocatalytic reduction CO2 into CO. It reported a novel and simple method to prepare a 3D g-C3N4 foam with micron-sized porous structures using ultrastable foam as a soft template for the first time. Moreover, Cu2O QDs are loaded onto 3D g-C3N4 foam through a simple photodeposition strategy. Systematically characterization demonstrated that g-C3N4 foam not only act as an excellent carrier for Cu2O QDs, but also greatly improve the photocatalytic performance by enhancing CO2 adsorption and gas transfer. Simultaneously, the rationally designed g-C3N4 foam/Cu2O QDs exhibited notablely enhancement in photocatalytic performance with 3.9 times and 11 times higher than that of g-C3N4 foam and bulk g-C3N4 powder. The excellent photocatalytic activity can be attributed to the unique porous structure and the synergistic effect between g-C3N4 foam and Cu2O QDs, which can speed up the transfer of charge carriers and urged the cumulation of photo-generated electrons on the Cu2O QDs. Our work provides new ideas for constructing 0D/3D hierarchical photocatalytic systems, which may provide guidance on designing efficient photocatalysts to maximize photocatalyst kinetics.


Assuntos
Dióxido de Carbono , Cobre/química , Nitrilas/química , Pontos Quânticos/química , Adsorção , Dióxido de Carbono/química , Dióxido de Carbono/isolamento & purificação , Oxirredução , Fotólise
16.
Environ Int ; 126: 289-297, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30825747

RESUMO

Owing to insufficient active sites, strongly bound excitons and insufficient optical absorption, polymer semiconductors have only shown mild activity as potential candidates for photocatalysis. A g-C3N4 with improved optical absorption capacity, charge transfer performance and porosity was successfully prepared by a one-step NH4Cl-assisted route. Interaction of melamine with NH4Cl preparation of Porous g-C3N4(CN-xy) with active functional groups modified pore wall shown to result in highly crystalline species with a maximum π-π layer stacking distance of heptazine units of 0.321 nm, decreases the optical band gap from 2.80 to 2.13 eV and maximum surface area reached 56.485 m2 g-1. The balanced improvement of the multiple defects of g-C3N4 makes the photocatalytic degradation of RhB and the photocatalytic hydrogen production efficiency 4 and 5 times higher than the pristine g-C3N4, respectively.


Assuntos
Cloreto de Amônio/química , Hidrogênio/química , Nitrilas/química , Cloreto de Amônio/efeitos da radiação , Corantes/química , Elétrons , Luz , Nitrilas/efeitos da radiação , Oxirredução , Rodaminas/química , Triazinas/química
17.
Drug Dev Ind Pharm ; 45(6): 905-913, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30744433

RESUMO

The aim of this study was to determine the effect of varying excipient content on the formation and physical properties of 3 D printed tablets. Fifteen different excipient preparations were formed into tablets with radii of 5 mm and thickness of 2 mm, using binder jetting (BJ). The tablets were analyzed by assessing visual and microstructural appearance, friability, hardness, and disintegration time. We found that filling agents with high water solubility (e.g. D-sucrose), binding agents with a high viscosity in solution (e.g. polyethylene glycol 4000) and moistening agent with higher water content can increase the bonding strength and hardness of the 3 D printed tablets and prolonged their disintegration time. This work has demonstrated that the type of excipient and its concentration affects the properties of the 3 D printed tablet. This article may be used as a guide for elucidation of the effects of using conventional tablet excipients in the field of 3 D printed pharmaceuticals. The present work should enable the identification of excipients that satisfy requirements, reduce analysis time, and improve efficiency.


Assuntos
Composição de Medicamentos/métodos , Excipientes/química , Impressão Tridimensional , Comprimidos/química , Química Farmacêutica , Composição de Medicamentos/tendências , Dureza , Pós , Solubilidade , Viscosidade , Água/química
18.
Chem Commun (Camb) ; 54(83): 11713-11716, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30204163

RESUMO

A superhydrophobic and superaerophilic surface was fabricated by facile self-assembly of silica nanoparticle/PDMS composites. The relevant superaerophilic surface showed excellent adhesion to air bubbles in an aqueous environment. With bubbles adhering to the superaerophilic surface, the density of the whole system was adjustable, which was applied to induce a diving-floating locomotion in an aqueous environment.

19.
J Colloid Interface Sci ; 532: 517-526, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30103134

RESUMO

In this work, we constructed a sensing system on Janus paper with hydrophilic side and hydrophobic side via depositing polymer precursor onto one side of qualitative filter paper. Water in humid environment (including liquid water, condensed moisture airflow and gaseous humid atmosphere) will be captured and gathered in the hydrophilic region of Janus paper due to the asymmetric hydrophobicity and hygroscopicity, which can induce the novel directional deformation. Additionally, MWCNTs (multiwalled carbon nanotubes) were loaded onto hydrophobic region beforehand to construct conductive network. The resistance of the conductive network changes synergistically as the Janus paper deforms in humid environment. Thus, the novel Janus paper realized the induction of environment humid factors, and conversion from the deformation signals to the desirable electric signals. The Janus paper also shows excellent stability in cycle use.

20.
Drug Dev Ind Pharm ; 44(12): 1918-1923, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30027774

RESUMO

Individualized medicine is a new direction in the field of modern pharmacy. In this study, we assessed the feasibility and accuracy of 3D printing techniques for the preparation of individualized doses of mouth-disintegrating tablets of warfarin. Warfarin sodium, D-sucrose, pregelatinized starch, povidone K30, microcrystalline cellulose, and silicon dioxide (at a ratio of 1:42.45:46.15:5.1:4.9:0.4) were mixed and used as the printing powder in the 3D printer; preset parameters were used. The dosage of the tablet was controlled by the number of printing layers. The content, dose uniformity, dose accuracy, hardness, friability, disintegration time, dissolution, and the microstructural and overall appearance were determined to evaluate the printed tablets. For the doses of 3, 2, and 1 mg that were produced in the experiment, the disintegration times were 50.0 ± 5.2, 35.7 ± 4.3, and 11.0 ± 2.2 s, respectively, and the relative errors of the dose were -2.33, -1.50, and 0%, respectively. The other indicators were consistent with the preparation requirements of pharmaceutical tablets. It is possible to prepare tablets with excellent properties and controlled drug doses by using 3D printing techniques. This technology will be an important means to achieve individualized medicine.


Assuntos
Anticoagulantes/química , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Impressão Tridimensional , Varfarina/química , Administração Oral , Anticoagulantes/administração & dosagem , Química Farmacêutica , Preparações de Ação Retardada/administração & dosagem , Composição de Medicamentos/instrumentação , Liberação Controlada de Fármacos , Excipientes/química , Estudos de Viabilidade , Humanos , Comprimidos , Varfarina/administração & dosagem
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