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1.
Opt Express ; 31(9): 13875-13887, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157263

RESUMO

Self-assembled photonic structures have greatly expanded the paradigm of optical materials due to their ease of access, the richness of results offered and the strong interaction with light. Among them, photonic heterostructure shows unprecedent advances in exploring novel optical responses that only can be realized by interfaces or multiple components. In this work, we realize visible and infrared dual-band anti-counterfeiting using metamaterial (MM) - photonic crystal (PhC) heterostructures for the first time. Sedimentation of TiO2 nanoparticles in horizontal mode and polystyrene (PS) microspheres in vertical mode self-assembles a van der Waals interface, connecting TiO2 MM to PS PhC. Difference of characteristic length scales between two components support photonic bandgap engineering in the visible band, and creates a concrete interface at mid-infrared to prevent interference. Consequently, the encoded TiO2 MM is hidden by structurally colored PS PhC and visualized either by adding refractive index matching liquid or by thermal imaging. The well-defined compatibility of optical modes and facility in interface treatments further paves the way for multifunctional photonic heterostructures.

2.
J Environ Manage ; 322: 115995, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037591

RESUMO

As a measure of ecosystems' contribution to human well-being, the concept of Gross Ecosystem Product (GEP) is an integrated monetary index for the evaluation of final ecosystem services, which has attracted widespread attention around the world. In China, both national and local governments have launched a series of GEP accounting pilot projects, with the aim to incorporate this new concept into real world decision-making. However, a critical review of these practices remains lacking, especially regarding their current status and problems. In this study, by performing a systematic review and data integration of current literature and government documents, we comprehensively described the GEP accounting practices in China, including pilot project's coverage, accounting methods, and policy application. Then, we identified five major problems in current GEP accounting practices in China, which prevent GEP from being accurately measured in the short term. We proposed that GEP accounting should be a constantly evolving process with both long-term and short-term improvement goals. More in detail, the accuracy issues in GEP accounting require longer periods of time to resolve; while its repeatability, comparability, and applicability should be improved in the short term, so that it can be incorporated into decision-making. In response to these challenges, we suggested the adaptation of GEP accounting index screening principles as a possible future direction, which can help to apply GEP results in the current stages of decision making. By improving GEP concept and accounting, it will be possible to establish a unified comparable GEP accounting system and reduce the gap between the GEP and decision-making.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Projetos Piloto
3.
Opt Express ; 29(6): 8872-8879, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820328

RESUMO

We propose a radar-infrared bi-stealth rasorber that not only provides broad microwave absorptivity and low infrared emissivity but also possesses a microwave transmission window at low frequency. It is composed of three functional layers, which are carefully designed to independently control the infrared emission, microwave absorption, and transmission, respectively. The structure exhibits broadband (8.1-19.3 GHz) and high-efficiency (>90%) absorption. A transmission window appears at low frequency with a transmission peak of 80% at 2.68 GHz. The thermal emissivity of the structure is about 0.27 in the atmosphere window, which is close to that of metal. Moreover, the total thickness of the proposed structure is only 3.713 mm. The low-infrared-emissivity, high-microwave-absorption and frequency-selective-transmission properties promise it will find potential applications in various stealth fields.

4.
J Chem Phys ; 155(19): 194106, 2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34800956

RESUMO

The Poisson-Nernst-Planck (PNP) model plays an important role in simulating nanopore systems. In nanopore simulations, the large-size nanopore system and convection-domination Nernst-Planck (NP) equations will bring convergence difficulties and numerical instability problems. Therefore, we propose an improved finite element method (FEM) with an inverse averaging technique to solve the three-dimensional PNP model, named inverse averaging FEM (IAFEM). At first, the Slotboom variables are introduced aiming at transforming non-symmetric NP equations into self-adjoint second-order elliptic equations with exponentially behaved coefficients. Then, these exponential coefficients are approximated with their harmonic averages, which are calculated with an inverse averaging technique on every edge of each tetrahedral element in the grid. Our scheme shows good convergence when simulating single or porous nanopore systems. In addition, it is still stable when the NP equations are convection domination. Our method can also guarantee the conservation of computed currents well, which is the advantage that many stabilization schemes do not possess. Our numerical experiments on benchmark problems verify the accuracy and robustness of our scheme. The numerical results also show that the method performs better than the standard FEM when dealing with convection-domination problems. A successful simulation combined with realistic chemical experiments is also presented to illustrate that the IAFEM is still effective for three-dimensional interconnected nanopore systems.

5.
Nano Lett ; 20(3): 2129-2136, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32078769

RESUMO

Valley pseudospin in two-dimensional (2D) transition-metal dichalcogenides (TMDs) allows optical control of spin-valley polarization and intervalley quantum coherence. Defect states in TMDs give rise to new exciton features and theoretically exhibit spin-valley polarization; however, experimental achievement of this phenomenon remains challenges. Here, we report unambiguous valley pseudospin of defect-bound localized excitons in CVD-grown monolayer MoS2; enhanced valley Zeeman splitting with an effective g-factor of -6.2 is observed. Our results reveal that all five d-orbitals and the increased effective electron mass contribute to the band shift of defect states, demonstrating a new physics of the magnetic responses of defect-bound localized excitons, strikingly different from that of A excitons. Our work paves the way for the manipulation of the spin-valley degrees of freedom through defects toward valleytronic devices.

6.
J Cell Physiol ; 235(10): 7003-7017, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32037547

RESUMO

Hepatocellular carcinoma (HCC) is a lethal malignancy worldwide. HCC has traits of late diagnosis and high recurrence. This study explored potential diagnosis and prognosis significance of phospholipase C epsilon 1 (PLCE1) in HCC. The messenger RNA (mRNA) levels and diagnostic value of PLCE1 were determined by real-time polymerase chain reaction and online databases GEPIA, oncomine, and GSE14520 data set. Survival analysis used the Kaplan-Meier Plotter website. Cell cycle, proliferation, migration, and invasion assays were performed with downregulated PLCE1 expression in HCC-M and HepG2 cell lines. PLCE1 was differentially expressed and highly expressed in tumors and had low expression in nontumor tissues (all p < .05). The diagnostic value of PLCE1 was validated with the datasets (all p < .01, all areas under curves > 0.7). PLCE1 mRNA expression was associated with the overall and relapse-free survival (both p < .05). Functional experiments indicated that downregulation of PLCE1 expression led to increased G1 stage in cell cycle and decreased cell proliferation, migration, and invasion compared with a negative control group (all p ≤ .05). The oncogene PLCE1 was differentially expressed in HCC and non-HCC tissues. It is a candidate for diagnosis and serves as prognosis biomarker. PLCE1 influenced survival by affecting the cell cycle, proliferation, migration, and invasion ability.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Ciclo Celular/genética , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Hepáticas/genética , Oncogenes/genética , Fosfoinositídeo Fosfolipase C/genética , Adulto , Apoptose/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Intervalo Livre de Doença , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Masculino , Recidiva Local de Neoplasia/genética , Prognóstico , RNA Mensageiro/genética
7.
Microb Pathog ; 144: 104174, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32224212

RESUMO

Ginseng exhibits multiple medicinal properties, including the improvement of immune function and enhancing disease resistance. In this study, we investigated the inhibitory effects of ginsenoside Rg3 on grass carp reovirus (GCRV) infection of grass carp ovarian (CO) epithelial cells, in order to provide a baseline framework for future high-efficacy antiviral drug screening investigations. Ginsenoside Rg3 was added to GCRV-infected CO cells, and cells were cultured at 27 °C before cell proliferation was measured by MTT assays. Label-free real-time cellular analysis (RTCA) after 72 h of experimentation demonstrated that 100 µg/mL ginsenoside Rg3 treatment had the highest inhibitory effect on GCRV (among 1,10,100 µg/mL treatments). We then measured the capacity for cellular antioxidant ability. Cells treated with 1,10,100 µg/mL ginsenoside Rg3 exhibited increases in Total Antioxidant Capacity activity relative to controls, respectively. Furthermore, Antioxidant assay and reverse transcript quantitative polymerase chain reaction (RT-qPCR) showed that ginsenoside Rg3 were efficient to restrain the replication of GCRV in CO cells. Expression analysis of immune-related genes via RT-qPCR showed that treatment with ginsenoside Rg3 promoted expression of IRF-3 and IRF-7 increases, respectively. Moreover, expression of IFN-1 was induced, which then inhibition the expression of tumor necrosis factor-alpha (TNF-α). In conclusion, we demonstrated that ginsenoside Rg3 promotes CO cell proliferation, inhibits GCRV activity, promotes CO cell immune activities, and thereby enhances the resistance of CO to GCRV infection.


Assuntos
Antivirais/farmacologia , Carpas/virologia , Ginsenosídeos/farmacologia , Reoviridae/crescimento & desenvolvimento , Replicação Viral/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Feminino , Fatores Reguladores de Interferon/biossíntese , Interferon Tipo I/biossíntese , Ovário/citologia , Fator de Necrose Tumoral alfa/biossíntese , Replicação Viral/fisiologia
8.
J Cell Biochem ; 120(10): 18246-18265, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31211449

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is among the most common and lethal malignancies worldwide. Apolipoproteins (APOs) have been reported increasingly for their relationships with tumors. We aim at exploring the potential relationships of apolipoprotein A (APOA) and apolipoprotein C (APOC) family members with HCC. METHODS: A data set, containing 212 hepatitis B virus-related HCC patients, was used for analysis. The diagnostic and prognostic ability of APOA and APOC family genes was figured out. Risk score models and nomograms were developed for the HCC prognosis prediction. Moreover, molecular mechanism exploration were identified biological processes and metabolic pathways of these genes involved in. Validation analysis was carried out using online website. RESULTS: APOA1, APOC1, APOC3, and APOC4 showed robust diagnosis significance (all P < 0.05). APOA4, APOC3, and APOC4 were associated with the overall survival (OS) while APOA4 and APOC4 were linked to recurrence-free survival (RFS, all P ≤ 0.05). Risk score models and nomograms had the advantage of predicting OS and RFS for HCC. Molecular mechanism exploration indicated that these genes were involved in the steroid metabolic process, the PPAR signaling pathway, and fatty acid metabolism. Besides that, validation analysis revealed that APOC1 and APOC4 had an association with OS; and APOC3 was associated with OS and RFS (all P ≤ 0.05). CONCLUSIONS: APOA1, APOC1, APOC3, and APOC4 are likely to be potential diagnostic biomarkers and APOC3 and APOC4 are likely to be potential prognostic biomarkers for hepatitis B virus-related HCC. They may be involved in the steroid metabolic process, PPAR signaling pathway, and fatty acid metabolism.


Assuntos
Apolipoproteínas A/genética , Apolipoproteínas C/genética , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Hepatite/complicações , Neoplasias Hepáticas/genética , RNA Mensageiro/genética , Apolipoproteínas A/metabolismo , Apolipoproteínas C/metabolismo , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Redes Reguladoras de Genes , Hepatite/virologia , Vírus da Hepatite B/fisiologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Nomogramas , Prognóstico , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo
9.
BMC Biotechnol ; 18(1): 51, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30157831

RESUMO

BACKGROUND: Fibroblast growth factor 9 (FGF9) is a heparin-binding growth factor, secreted by both mesothelial and epithelial cells, which participates in hair follicle regeneration, wound healing, and bone development. A suitable source of recombinant human FGF9 (rhFGF9) is needed for research into potential clinical applications. We present that expression of oleosin-rhFGF9 fusion protein in safflower (Carthamus tinctorius L.) seeds stimulates hair growth and wound healing. RESULTS: The oleosin-rhFGF9 expressed in safflower seeds, in which it localizes to the surface of oil bodies. The expression of oleosin-rhFGF9 was confirmed by polyacrylamide gel electrophoresis and western blotting. According to BCA and Enzyme-linked immunosorbent assay (ELISA) assay, the results show that the expression level of oleosin-rhFGF9 was 0.14% of oil body protein. The oil body bound oleosin-rhFGF9 showed mitogenic activity towards NIH3T3 cells in a methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. The efficacy of oil body bound oleosin-rhFGF9 in promoting hair growth and wound healing was investigated in C57BL/6 mice. In a hair regeneration experiment, 50 µg/µl oil body bound oleosin-rhFGF9 was applied to the dorsal skin of mice in the resting phase of the hair growth cycle. After 15 days, thicker hair and increased number of new hairs were seen compared with controls. Furthermore, the number of new hairs was greater compared with rhFGF9-treated mice. The hair follicles of mice treated with oil body bound oleosin-rhFGF9 expressed ß-catenin more abundantly. In a wound healing experiment, dorsal skin wounds were topically treated with 50 µg/µl oil body bound oleosin-rhFGF9. Wound healing was quicker compared with mice treated with rhFGF9 and controls, especially in the earlier stages of healing. CONCLUSIONS: The oil body bound oleosin-rhFGF9 promotes both hair growth and wound healing. It appears to promote hair growth, at least in part, by up-regulating ß-catenin expression. The potential of oil body bound oleosin-rhFGF9 as an external drug can treat the alopecia and wounds or use in further clinical application.


Assuntos
Carthamus tinctorius/genética , Fator 9 de Crescimento de Fibroblastos/administração & dosagem , Fator 9 de Crescimento de Fibroblastos/genética , Cabelo/crescimento & desenvolvimento , Gotículas Lipídicas/metabolismo , Proteínas de Plantas/administração & dosagem , Proteínas de Plantas/genética , Ferimentos e Lesões/tratamento farmacológico , Animais , Carthamus tinctorius/metabolismo , Fator 9 de Crescimento de Fibroblastos/metabolismo , Expressão Gênica , Cabelo/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Proteínas de Plantas/metabolismo , Transporte Proteico , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Cicatrização , Ferimentos e Lesões/genética , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/fisiopatologia , beta Catenina/genética , beta Catenina/metabolismo
10.
J Nanobiotechnology ; 16(1): 62, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30165861

RESUMO

BACKGROUND: Epidermal growth factor (EGF) can promote cell proliferation as well as migration, which is feasible in tissue wound healing. Oil bodies have been exploited as an important platform to produce exogenous proteins. The exogenous proteins were expressed in oil bodies from plant seeds. The process can reduce purification steps, thereby significantly reducing the purification cost. Mostly, the diameter of oil body particle ranges between 1.0 and 1.5 µm in the safflower seeds, however, it reduces to 700-1000 nm in the transgenic safflower seeds. The significant reduction of particle size in transgenic seeds is extremely beneficial to skin absorption. RESULTS: The diameter of oil body in the transgenic safflower seeds was recorded in the range of 700-1000 nm. The smaller particle size improved their skin absorption. The expression level of oleosin-hEGF-hEGF in T3 transgenic seeds was highest at 69.32 mg/g of seeds. The oil body expressing oleosin-hEGF-hEGF had significant proliferative activity on NIH/3T3 cells and improved skin regeneration thereby accelerating wound healing in rats. The wound coverage rate exceeded 98% after treatment for 14 days with oil body expressing oleosin-hEGF-hEGF, while the saline without EGF group and wild type oil body group both showed less than 80%. The neonatal fibroblast and collagen were found to be increased in the safflower oil body expressing oleosin-hEGF-hEGF treatment group. TGF-ß1, bFGF and VEGF were noted as important growth factors in the repair of cutaneous wounds. Their expression level increased after 4 and 7 day treatment, but decreased after 14 days. Therefore, it can promote skin regeneration to accelerate wounds healing. CONCLUSIONS: The expression of oleosin-hEGF-hEGF in T3 transgenic seeds was 80.43 ng/µL oil body. It had significant proliferative activity on NIH/3T3 cells and improved skin regeneration to accelerate wound healing in rats. The expression process of TGF-ß1, bFGF and VEGF increased at first and then gradually declined.


Assuntos
Fator de Crescimento Epidérmico/química , Gotículas Lipídicas/química , Proteínas de Plantas/química , Pele/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células NIH 3T3 , Tamanho da Partícula , Óleos de Plantas/química , Ratos , Ratos Wistar , Regeneração/efeitos dos fármacos , Sementes/química , Propriedades de Superfície , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/imunologia
11.
Med Sci Monit ; 24: 3578-3590, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29808834

RESUMO

BACKGROUND Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related death worldwide. The relationships of alcohol dehydrogenase (ADH) enzymes, encoded by the genes ADH1 (1A), ADH1B (ADH2), ADH1C (ADH3), ADH4, ADH5, ADH6, and ADH7, with NSCLC have not been studied. The aim of this study was to explore the associations between NSCLC prognosis and the expression patterns of ADH family members. MATERIAL AND METHODS The online resource Metabolic gEne RApid Visualizer was used to assess the expression patterns of ADH family members in normal and primary lung tumor tissues. The GeneMANIA plugin of Cytoscape software and STRING website were used to evaluate the relationships of the 7 ADH family members at the gene and protein levels. Gene ontology enrichment analysis and KEGG pathway analysis were performed using DAVID. The online website Kaplan-Meier Plotter was used to construct survival curves between NSCLC and ADH isoforms. RESULTS The prognosis of patients with high expression levels of the ADH1B, ADH1C, ADH4, and ADH5 genes was better than those with low expression in adenocarcinoma and all (containing adenocarcinoma and squamous cell cancer) histological types (all P<0.05). Low expression of ADH7 was associated with a better prognosis in patients with both the adenocarcinoma and squamous cell cancer histological types (P=9e-05). Moreover, expression of ADH family members was associated with smoking status, clinical stage, and chemotherapy status. CONCLUSIONS ADH1B, ADH1C, ADH4, ADH5, and ADH7 appear to be useful biomarkers for the prognosis of NSCLC patients.


Assuntos
Álcool Desidrogenase/metabolismo , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Neoplasias Pulmonares/enzimologia , Álcool Desidrogenase/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Prognóstico , Fumar/efeitos adversos , Resultado do Tratamento
12.
Int J Mol Sci ; 18(10)2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-29057820

RESUMO

Recombinant human fibroblast growth factor 10 (rhFGF-10) is frequently used to treat patients with skin injuries. It can also promote hair growth. However, the effective application of rhFGF-10 is limited because of its poor stability and transdermal absorption. In this study, polymerase chain reaction (PCR) and Southern blotting were used to identify transgenic safflowers carrying a gene encoding an oleosin-rhFGF-10 fusion protein. The size and structural integrity of oleosin-rhFGF-10 in oil bodies extracted from transgenic safflower seeds was characterized by polyacrylamide gel electrophoresis and western blotting. Oil body extracts containing oleosin-rhFGF-10 were topically applied to mouse skin. The absorption of oleosin-rhFGF-10 was studied by immunohistochemistry. Its efficiency in promoting wound healing and hair regeneration were evaluated in full thickness wounds and hair growth assays. We identified a safflower line that carried the transgene and expressed a 45 kDa oleosin-rhFGF-10 protein. Oil body-bound oleosin-rhFGF-10 was absorbed by the skin with higher efficiency and speed compared with prokaryotically-expressed rhFGF-10. Oleosin-rhFGF-10 also enhanced wound closure and promoted hair growth better than rhFGF-10. The application of oleosin-rhFGF-10 in oil bodies promoted its delivery through the skin, providing a basis for improved therapeutic effects in enhancing wound healing and hair growth.


Assuntos
Carthamus tinctorius/química , Portadores de Fármacos/química , Fator 10 de Crescimento de Fibroblastos/administração & dosagem , Folículo Piloso/metabolismo , Proteínas de Plantas/química , Cicatrização , Pelo Animal/efeitos dos fármacos , Pelo Animal/crescimento & desenvolvimento , Animais , Fator 10 de Crescimento de Fibroblastos/farmacocinética , Fator 10 de Crescimento de Fibroblastos/farmacologia , Folículo Piloso/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
13.
Environ Monit Assess ; 188(6): 382, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27240853

RESUMO

The Three-Rivers Headwater Region (TRHR) is the headwater of the Yangtze River Basin (YARB), Yellow River Basin (YRB), and Lancang River Basin (LRB); it is known as China's 'Water Tower' owing to its important supply of freshwater. In order to assess ecosystem changes in the TRHR during 2000-2012, we systematically and comprehensively evaluated a combination of model simulation results and actual observational data. The results showed the following: (1) Ecosystem pattern was relatively stable during 2000-2010, with a slight decrease in farmland and desert areas, and a slight increase in grassland and wetland/water-body areas. (2) A warmer and wetter climate, and ecological engineering, caused the vegetation cover and productivity to significantly improve. (3) Precipitation was the main controlling factor for streamflow. A significant increase in precipitation during 2000-2012 resulted in an obvious increase in annual and seasonal streamflow. Glacier melting also contributed to the streamflow increase. (4) The total amount of soil conservation increased slightly from 2000 to 2012. The increase in precipitation caused rainfall erosivity to increase, which enhanced the intensity of soil erosion. The decrease in wind speed decreased wind erosion and the frequency of sandstorms. (5) The overall habitat quality in the TRHR was stable between 2000 and 2010, and the spatial pattern exhibited obvious heterogeneity. In some counties that included nature reserves, habitat quality was slightly higher in 2010 than in 2000, which reflected the effectiveness of the ecological restoration. Overall, the aforementioned ecosystem changes are the combined results of ecological restoration and climate change, and they are likely a local and temporary improvement, rather than a comprehensive and fundamental change. Therefore, more investments and efforts are needed to preserve natural ecosystems.


Assuntos
Mudança Climática , Ecossistema , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Modelos Teóricos , Rios/química , China , Pradaria , Camada de Gelo/química , Chuva , Solo/química , Áreas Alagadas , Vento
14.
J Phys Chem B ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949996

RESUMO

So far, the existing Poisson-Boltzmann (PB) solvers that accurately take into account the interface jump conditions need a pregenerated body-fitted mesh (molecular surface mesh). However, qualified biomolecular surface meshing and its implementation into numerical methods remains a challenging and laborious issue, which practically hinders the progress of further developments and applications of a bunch of numerical methods in this field. In addition, even with a molecular surface mesh, it is only a low-order approximation of the original curved surface. In this article, an interface-penalty finite element method (IPFEM), which is a typical unfitted finite element method, is proposed to solve the Poisson-Boltzmann equation (PBE) without requiring the user to generate a molecular surface mesh. The Gaussian molecular surface is used to represent the molecular surface and can be automatically resolved with a high-order approximation within our method. Theoretical convergence rates of the IPFEM for the linear PB equation have been provided and are well validated on a benchmark problem with an analytical solution (we also noticed from numerical examples that the IPFEM has similar convergence rates for the nonlinear PBE). Numerical results on a set of different-sized biomolecules demonstrate that the IPFEM is numerically stable and accurate in the calculation of biomolecular electrostatic solvation energy.

15.
J Comput Chem ; 34(24): 2065-78, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23740647

RESUMO

A parallel finite element simulator, ichannel, is developed for ion transport through three-dimensional ion channel systems that consist of protein and membrane. The coordinates of heavy atoms of the protein are taken from the Protein Data Bank and the membrane is represented as a slab. The simulator contains two components: a parallel adaptive finite element solver for a set of Poisson-Nernst-Planck (PNP) equations that describe the electrodiffusion process of ion transport, and a mesh generation tool chain for ion channel systems, which is an essential component for the finite element computations. The finite element method has advantages in modeling irregular geometries and complex boundary conditions. We have built a tool chain to get the surface and volume mesh for ion channel systems, which consists of a set of mesh generation tools. The adaptive finite element solver in our simulator is implemented using the parallel adaptive finite element package Parallel Hierarchical Grid (PHG) developed by one of the authors, which provides the capability of doing large scale parallel computations with high parallel efficiency and the flexibility of choosing high order elements to achieve high order accuracy. The simulator is applied to a real transmembrane protein, the gramicidin A (gA) channel protein, to calculate the electrostatic potential, ion concentrations and I - V curve, with which both primitive and transformed PNP equations are studied and their numerical performances are compared. To further validate the method, we also apply the simulator to two other ion channel systems, the voltage dependent anion channel (VDAC) and α-Hemolysin (α-HL). The simulation results agree well with Brownian dynamics (BD) simulation results and experimental results. Moreover, because ionic finite size effects can be included in PNP model now, we also perform simulations using a size-modified PNP (SMPNP) model on VDAC and α-HL. It is shown that the size effects in SMPNP can effectively lead to reduced current in the channel, and the results are closer to BD simulation results.


Assuntos
Brevibacillus/metabolismo , Simulação por Computador , Gramicidina/metabolismo , Canais Iônicos/metabolismo , Modelos Biológicos , Brevibacillus/química , Gramicidina/química , Canais Iônicos/química , Transporte de Íons , Modelos Moleculares , Conformação Proteica , Multimerização Proteica , Software
16.
Biomimetics (Basel) ; 8(4)2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37622953

RESUMO

The Arithmetic Optimization Algorithm (AOA) is a meta-heuristic algorithm inspired by mathematical operators, which may stagnate in the face of complex optimization issues. Therefore, the convergence and accuracy are reduced. In this paper, an AOA variant called ASFAOA is proposed by integrating a double-opposite learning mechanism, an adaptive spiral search strategy, an offset distribution estimation strategy, and a modified cosine acceleration function formula into the original AOA, aiming to improve the local exploitation and global exploration capability of the original AOA. In the proposed ASFAOA, a dual-opposite learning strategy is utilized to enhance population diversity by searching the problem space a lot better. The spiral search strategy of the tuna swarm optimization is introduced into the addition and subtraction strategy of AOA to enhance the AOA's ability to jump out of the local optimum. An offset distribution estimation strategy is employed to effectively utilize the dominant population information for guiding the correct individual evolution. In addition, an adaptive cosine acceleration function is proposed to perform a better balance between the exploitation and exploration capabilities of the AOA. To demonstrate the superiority of the proposed ASFAOA, two experiments are conducted using existing state-of-the-art algorithms. First, The CEC 2017 benchmark function was applied with the aim of evaluating the performance of ASFAOA on the test function through mean analysis, convergence analysis, stability analysis, Wilcoxon signed rank test, and Friedman's test. The proposed ASFAOA is then utilized to solve the wireless sensor coverage problem and its performance is illustrated by two sets of coverage problems with different dimensions. The results and discussion show that ASFAOA outperforms the original AOA and other comparison algorithms. Therefore, ASFAOA is considered as a useful technique for practical optimization problems.

17.
J Alzheimers Dis ; 93(2): 435-448, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37038816

RESUMO

BACKGROUND: Patients with Alzheimer's disease (AD) have considerably increased globally as a result of population aging, placing a significant burden on the global economy and the medical system. The outcome of clinical trials for AD immunotherapy that solely targeted amyloid-ß (Aß) or phosphorylated tau protein (p-Tau) was unsatisfactory. Therefore, blocking both Aß and p-Tau's pathological processes simultaneously while also preventing their interaction may be the key to developing an effective AD therapy. OBJECTIVE: To develop a novel immunotherapy based on bispecific tandem scFv (TaFv) against AD. METHODS: Bispecific single-chain antibody that targets both Aß and p-Tau were obtained using E. coli expression system. Biological ability of TaFvs were determined by ELISA, SDS-PAGE, and immunohistochemical assay. Recombinant adeno-associated virus 9 (rAAV9) were packaged to create TaFv. The in vivo activity of rAAV9 were detected in mouse, using biophotonic imaging and frozen section methods. RESULTS: The outcomes demonstrated that both Aß and p-Tau had a high affinity for the bispecific TaFv. Additionally, it can bind to the amyloid plaques and neuronal tangles in the brain slices of an AD mouse model. Moreover, the rAAV9 could infect neuronal cells, transverse the blood-brain barrier, and express TaFv in the mouse brain. CONCLUSION: This novel immunotherapy offers a fresh concept for the immunotherapy of AD and successfully delivers the double target antibody into the brain, acting on both pathogenic substances Aß and p-Tau.


Assuntos
Doença de Alzheimer , Anticorpos Biespecíficos , Camundongos , Animais , Doença de Alzheimer/patologia , Dependovirus/genética , Escherichia coli/metabolismo , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Encéfalo/patologia , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Biespecíficos/metabolismo , Imunoterapia , Modelos Animais de Doenças
18.
J Colloid Interface Sci ; 630(Pt A): 1-10, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36215819

RESUMO

Wind power is a promising electricity source. Nevertheless, wind turbine blade icing can cause severe problems in turbine operation. In this study, SiO2 spherical nanoparticles (∼90 nm), produced by RF (radio frequency) plasma spheroidization, were mixed with E51, PDMS, and ethyl acetate, and sprayed on the surface of aluminum plates and regular power windmill fan blades which were already coated with polyurethane primer. XPS and IR spectroscopies revealed the development of SiC and SiPh (Ph = phenolic ring) bonds, whose formation should be favored by the ultrasound and curing processes at 50 °C. The integrity of the coating/substrate interface, whose strength is ascribed to hydrogen bonds, was maintained after 100 icing-melting cycles. The coatings display superhydrophobic behavior and excellent anti-icing performance, along with stability in abrasion, sunlight and self-cleaning ability towards solid pollutants.

19.
Ecotoxicology ; 21(1): 260-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21915736

RESUMO

The construction of a normalized cDNA library is a popular tool for identifying novel biomarkers for monitoring environmental pollution. In the present study, a normalized cDNA library was constructed from the river snail Bellamya aeruginosa after exposure to Cu(2+) by using the SMART technique. The titer of the cDNA library was 1.78 × 10(6) pfu/ml, with a recombinant efficiency of 95.8%. In addition, from 6,000 randomly selected and sequenced clones, 5,473 high-quality ESTs were identified. After processing the sequences, 3,961 unigenes representing 897 contigs and 3,064 singlets were obtained with 27.6% redundancy. Analysis of expressed sequenced tags using COG and GO annotation and KEGG pathway data showed that a large group of genes related to growth and development, signal transduction, and defense mechanisms were present in the cDNA library. Based on our findings, this normalized cDNA library will provide a valuable resource for further research on functional genes and ecotoxicology in B. aeruginosa.


Assuntos
Cobre/toxicidade , Monitoramento Ambiental/métodos , Biblioteca Gênica , Caramujos/efeitos dos fármacos , Poluentes Químicos da Água/análise , Animais , Clonagem Molecular , Etiquetas de Sequências Expressas , RNA/isolamento & purificação , Rios , Análise de Sequência de RNA
20.
Mol Immunol ; 144: 26-34, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35172225

RESUMO

Disease-modifying passive immunotherapies focusing on removal of abnormal phosphorylated Tau (p-Tau) constitute promising treatments for Alzheimer's disease (AD). Although several prior immunotherapies targeting p-Tau appear to be beneficial against AD, they have limitations such as the low blood-brain barrier (BBB) penetration rate, short half-life of antibodies, and the likelihood of inflammation. To address these issues, we designed a novel immunotherapy for AD. To this end, a single chain antibody (scFv) targeting p-Tau was generated, and a recombinant adeno-associated virus that can cross the BBB (rAAV/BBB) was used as a vector to express scFv for at least 22 weeks in the mouse brain. Results showed that the scFv constructed in this study had a high affinity to p-Tau and could bind to neuronal tangles in the section of brains of AD model mice. Moreover, the rAAV/BBB could cross the BBB, infect neuronal cells, and express scFv. This novel immunotherapy could effectively deliver scFv into the brain and resulted in a continuous expression of scFv in vivo, suggesting its potential for the treatment of AD.


Assuntos
Doença de Alzheimer , Animais , Anticorpos/metabolismo , Encéfalo/metabolismo , Dependovirus/metabolismo , Fatores Imunológicos , Imunoterapia , Camundongos , Camundongos Transgênicos
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