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1.
Sensors (Basel) ; 22(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35746373

RESUMO

To improve the ability of remote sensing technology in recognizing black-odorous water bodies in Hangzhou, this study analyzed the typical spectral characteristics of black-odorous water in Hangzhou based on measured spectral data and water quality parameters, including the transparency, dissolved oxygen, oxidation reduction potential, and ammonia nitrogen. The single-band threshold method, the normalized difference black-odorous water index (NDBWI) model, the black-odorous water index (BOI) model, and the color purity on a Commission Internationale de L'Eclairage (CIE) model were compared to analyze the spatial and temporal distribution characteristics of the black-odorous water in Hangzhou. The results showed that: (1) The remote sensing reflectance of black-odorous water was lower than that of ordinary water, the spectral curve was gentle, and the wave peak shifted toward the near-infrared direction in the wavelength range of 650-850 nm; (2) Among the aforementioned models, the normalized and improved normalized black-odorous water index methods had a higher accuracy, reaching 87.5%, and the threshold values for black-odorous water identification were 0.14 and 0.1, respectively; (3) From 2015 to 2018, the quantity of black-odorous water in the main urban area of Hangzhou showed a decreasing trend, and black-odorous water was mainly distributed in the Gongshu District and tended to appear in narrow rivers, densely populated areas, and factory construction sites. This study is expected to be of great practical value for the rapid tracking and monitoring of urban black-odorous water by using remote sensing technology for future work.


Assuntos
Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Odorantes , Tecnologia de Sensoriamento Remoto/métodos , Rios , Qualidade da Água
2.
Nanotechnology ; 31(20): 205702, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31986506

RESUMO

Electrochemical etching of silicon carbide (SiC) material has received increasing attention in recent years, due to its simple procedure, low cost and significance in the exploration of novel optoelectronic devices. In this paper, 4H-SiC substrates were electrochemically etched at a constant current density of 392.98 mA cm-2 in an electrolyte made up of hydrofluoric acid and deionized water. The layering of a SiC porous layer and periodic fluctuation of the voltage were witnessed for the first time, with the layering phenomenon corresponding well to the voltage period. However, no such phenomenon was observed when the SiC substrates were anodic etched under the same conditions with magnet stirring. As a result, the periodic variation of voltage was hypothesized to be the cause of regular layering during constant current electrochemical etching. Electrochemical etching in potentiostatic mode was thus performed at different voltages. We found that the diameter of the SiC nanopores increased while the thickness of the sidewall decreased with the increasing voltage. Based on the experimental findings, a model of mass transport was proposed. The mass transport process leads to periodic changes in resistance, hence the periodic change in voltage. This successfully explained the reason for the layering. Furthermore, SiC substrates were also electrochemically etched at high and low current densities, finding the existence of a threshold current density for the occurrence of the layering. Energy dispersive x-ray spectroscopy analysis showed that the composition of the SiC porous layer remained unchanged compared to the pure SiC wafer, implying that the peeling-off of the SiC porous layer obtained by electrochemical etching can be directly adopted for use on devices requiring a SiC porous structure.

3.
Chemphyschem ; 15(12): 2421-30, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-24953044

RESUMO

This manuscript presents a brief overview of recent advances in multistimuli-responsive supramolecular gels (MRSGs). The synthesis of MRSGs with faster and smarter responsive abilities to a variety of external stimuli, such as redox reagents, pH changes, ligands, and coupling reagents, is one key issue for the upgrade of current molecular motors, signal sensors, shape memory devices, drug delivery systems, display devices, and other devices. However, the design rules of MRSGs are still not well understood. The lack of information about the relationship between the spatial structure and gelation behavior of existing gelators means that the knowledge required to design new gelators by the addition of functional moieties to well-known gelators is lacking. Insights into the gelation pathway of known gelators may bring inspiration to researchers who want to exploit elegant designs and specific building blocks to obtain their own MRSGs with predictable stimuli-responsive abilities.

4.
Vaccine X ; 16: 100448, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38322611

RESUMO

Background: Information is limited regarding the effectiveness of the inactivated vaccine for COVID-19 approved in China in preventing infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) when administered in real-world conditions. Methods: We retrospectively surveyed 1352 patients with a positive SARS-CoV-2 nucleic acid test treated at a major tertiary medical center in Foshan city (Guangdong, China) between November 2022 and February 2023. The exposure group was patients who had previously received the COVID-19 vaccine, which included patients who had received different doses of the vaccine and different vaccine types. The primary outcome of this study was the effectiveness of the vaccine in preventing severe disease and death among SARS-CoV-2-infected patients. Results: We found a mortality rate of 12.1 % associated with COVID-19. The results showed that an increase in the number of vaccine doses was associated with a reduction in in-hospital mortality. When compared to unvaccinated patients, vaccinated patients had an 8.5 % lower mortality rate. There was also a statistically significant reduction in the risk of death among vaccinated patients compared to unvaccinated patients (OR = 0.521 [95 % CI, 0.366 to 0.741]). Patients who had received the vaccine had a 22.8 % reduction in the risk of severe disease. In addition, the use of antiviral drugs decreased progressively with increasing vaccine doses (P < 0.05). Of these, anticoagulation, Paxlovid, and mechanical ventilation were used least frequently in the one-dose group. Conclusions: The vaccines approved in China mitigated the incidence of severe COVID-19 and reduced mortality. These findings suggest that COVID-19 vaccination can help to control the pandemic.

5.
Sci Total Environ ; 944: 173841, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38866168

RESUMO

The coastal zone serves as a crucial hub for economic and population concentration. Amid the context of high-intensity development and global climate change, uncertain risks from diverse sources-including extreme weather events (i.e., high temperatures, typhoons, and excessive precipitation), natural disasters (i.e., floods, tsunamis, landslides, and mudslides), and societal disruptions (i.e., economic crises and viral diseases)-are escalating rapidly. Enhancing coastal resilience to minimize these risk impacts is progressively becoming a mandatory requirement for the sustainable development of coastal zones. However, existing research primarily focuses on distinct disasters, the ecological environment, or specific socio-economic aspects, thereby lacking a comprehensive theoretical framework and thorough analysis of the factors influencing coastal resilience. Here, we construct a theoretical framework centered on the unique traits and processes of coastal resilience, analyze the spatiotemporal evolution characteristics of coastal resilience from a grid and administrative division standpoint, and utilize geographic detectors to determine the factors influencing coastal resilience while considering the modifiable areal unit problem (MAUP). Our findings indicate that: (1) Coastal resilience in the East China Sea (ECS) initially declined but then increased, transitioning from a lower to a medium level. Barring the pressure index, other dimensional indices had an upward trend; (2) Continuous improvements were observed in coastal resilience across different land uses. Forests, waters, and oceans demonstrated higher resilience levels than other lands, with construction land resilience developing swiftly. The effect of changes in land use types on coastal resilience showed a rapid initial increase and subsequent decrease; (3) The change pattern of coastal resilience in the ECS is mainly unchanged and slightly increased. Areas with the most drastic changes were concentrated in Shanghai, northern Zhejiang, and central Fujian, with the main change patterns continuously rising; (4) The primary factors influencing coastal resilience in the ECS included gross domestic product and infrastructure construction level. Advanced industrial structure, technological and educational prowess, and effective government management are important determinants of coastal resilience development. The significance of human factors continues to grow. Our findings offer valuable insights for optimizing national spatial planning of coastal zones, responding to internal and external impacts, achieving resilient coastal zones, and implementing a comprehensive sustainable management approach.

6.
BMJ Open ; 13(11): e076573, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37914307

RESUMO

INTRODUCTION: Lung nodules are one of the most prevalent diseases. Medical imaging methods have a high false positive rate for distinguishing malignant nodules from benign nodules. Therefore, developing new technologies with high accuracy for screening malignant nodules is of great importance for lung nodule surveillance. Use of flow cytometry to detect biomarkers in blood macrophages (epitop detect in macrophages/macrophages) has opened a new era for early and noninvasive diagnosis of cancer. This planned study aims to examine whether the peripheral blood macrophage factors Apo10 and TKTL1 accurately distinguish malignant nodules from benign nodules. METHODS AND ANALYSES: We plan to enrol in this study 3825 participants with lung nodules who will attend their annual physical examination at Sun Yat-sen University Cancer Center. Apo10 and TKTL1 levels in all patients will be tested at 60 min after their last meal every 6 months during their 3-year follow-up. Biopsy or surgical pathology results will be collected as the gold standard to assess the accuracy of Apo10 and TKTL1 in distinguishing malignant nodules from benign nodules. The sensitivity, specificity, positive predictive value, negative predictive value and area under the receiving operating characteristic curve will also be evaluated. ETHICS AND DISSEMINATION: The study is approved by the medical ethics committee of Sun Yat-sen University (SL-G2022-005-02). The results of this study will be disseminated in peer-reviewed publications and presentations at international scientific meetings and will also be disseminated to the participants. TRIAL REGISTRATION NUMBER: ChiCTR2300073823; Pre-results.


Assuntos
Neoplasias Pulmonares , Neoplasias , Humanos , Biomarcadores Tumorais , Pulmão , Neoplasias Pulmonares/diagnóstico , Macrófagos , Estudos Prospectivos , Transcetolase
7.
Bioorg Med Chem Lett ; 21(19): 5818-21, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21855336

RESUMO

Aggregation and fibril formation of ß-amyloid peptides (Aß) is the key event in the pathogenesis of Alzheimer's disease. Many efforts have been made on the development of effective inhibitors to prevent Aß fibril formation or disassemble the preformed Aß fibrils. Peptide inhibitors with sequences homologous to the hydrophobic segments of Aß can alter the aggregation pathway of Aß, together with decrease of the cell toxicity. In this study, the conjugate of ferrocenoyl (Fc) with pentapeptide KLVFF (Fc-KLVFF), was synthesized by HBTU/HOBt protocol in solution. The inhibitory effect of Fc-KLVFF on Aß(1-42) fibril formation was evaluated by thioflavin T fluorescence assay, and confirmed by atomic force microscopy (AFM) and transmission electron microscopy (TEM) analyses. Fc-KLVFF shows high inhibitory effect towards the fibril formation of Aß(1-42). Additionally, the attachment of ferrocenoyl moiety onto peptides allows us to investigate the interaction between the inhibitor and Aß(1-42) in real-time by electrochemical method. As expected, tethering of ferrocenoyl moiety onto pentapeptide shows improved lipophilicity and significant resistance towards proteolytic degradation compared to its parent peptide.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Desenho de Fármacos , Compostos Férricos/síntese química , Compostos Férricos/farmacologia , Nootrópicos/síntese química , Nootrópicos/farmacologia , Oligopeptídeos/síntese química , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/patologia , Benzotiazóis , Avaliação Pré-Clínica de Medicamentos , Técnicas Eletroquímicas , Compostos Férricos/química , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Terapia de Alvo Molecular , Nootrópicos/química , Oligopeptídeos/química , Oxirredução , Peptídeos/química , Solubilidade , Tiazóis/química
8.
J Nanosci Nanotechnol ; 11(11): 10187-92, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413363

RESUMO

Carboxymethylated dextran (CMD)-coated magnetic iron oxide nanoparticles (MNPs) were synthesized using a co-precipitation method. Compared to neutral dextran coated MNPs, the CMD coating provides good dispersity and colloidal stability to the CMD-MNPs. In particular, the carboxyl groups on the CMD can be readily activated for covalent attachment of antibody molecules. The superparamagnetic property of the antibody-covered CMD-MNPs enables the captured antigen to be separated from the sample solution and CMD coating significantly reduces the nonspecific binding of the nanoparticles. Regeneration of the anti-BSA antibody-covered CMD-MNPs with NaOH does not significantly decrease the antibody activity, and the repeated magnetic separation and washing steps cause only small loss of the starting materials. The method was found to be highly reproducible (RSDs for BSA adsorption and desorption are between 0.78% and 5.1%). The anti-BSA antibody-covered CMD-MNPs possess good selectivity and are able to capture protein antigens from real samples.


Assuntos
Dextranos/química , Nanopartículas de Magnetita/química , Animais , Anticorpos/metabolismo , Bovinos , Técnicas de Imunoadsorção , Microscopia de Força Atômica , Ligação Proteica , Reprodutibilidade dos Testes , Soroalbumina Bovina/isolamento & purificação , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência
9.
Biochem J ; 419(1): 193-200, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19105793

RESUMO

Antimicrobial polypeptides, including lysozymes, have membrane perturbing activity and are well-documented effector molecules of innate immunity. In cystic fibrosis, a hereditary disease with frequent lung infection with Pseudomonas aeruginosa, the non-esterified fatty acid DA (docosahexaenoic acid), but not OA (oleic acid), is decreased, and DA supplementation has been shown to improve the clinical condition in these patients. We hypothesized that DA may, either alone or in conjunction with lysozyme, exert antibacterial action against Ps. aeruginosa. We found that DA and lysozyme synergistically inhibit the metabolic activity of Ps. aeruginosa, in contrast with OA. Electron microscopy and equilibrium dialysis suggest that DA accumulates in the bacterial membrane in the presence of lysozyme. Surface plasmon resonance with live bacteria and differential scanning calorimetry studies with bacterial model membranes reveal that, initially, DA facilitates lysozyme incorporation into the membrane, which in turn allows influx of more DA, leading to bacterial cell death. The present study elucidates a molecular basis for the synergistic action of non-esterified fatty acids and antimicrobial polypeptides, which may be dysfunctional in cystic fibrosis.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Muramidase/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/ultraestrutura , Varredura Diferencial de Calorimetria , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sinergismo Farmacológico , Humanos , Microscopia Eletrônica de Transmissão , Ressonância de Plasmônio de Superfície
10.
Colloids Surf B Biointerfaces ; 123: 15-22, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25222139

RESUMO

To enhance the solubility and improve the bioavailability of hydrophobic curcumin, a new kind of imprinted-like biopolymeric micelles (IBMs) was designed. The IBMs were prepared via co-assembly of gelatin-dextran conjugates with hydrophilic tea polyphenol, then crosslinking the assembled micelles and finally removing the template tea polyphenol by dialysis. The obtained IBMs show selective binding for polyphenol analogous drugs over other drugs. Furthermore, curcumin can be effectively encapsulated into the IBMs with 5×10(4)-fold enhancement of aqueous solubility. We observed the sustained drug release behavior from the curcumin-loaded IBMs (CUR@IBMs) in typical biological buffers. In addition, we found the cell uptake of CUR@IBMs is much higher than that of free curcumin. The cell cytotoxicity results illustrated that CUR@IBMs can improve the growth inhibition of HeLa cells compared with free curcumin, while the blank IBMs have little cytotoxicity. The in vivo animal study demonstrated that the IBMs could significantly improve the oral bioavailability of curcumin.


Assuntos
Curcumina/administração & dosagem , Curcumina/química , Portadores de Fármacos/química , Micelas , Animais , Biopolímeros/efeitos adversos , Biopolímeros/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/efeitos adversos , Células HeLa , Humanos , Camundongos , Microscopia de Fluorescência , Impressão Molecular , Polifenóis/química , Solubilidade
11.
Shanghai Kou Qiang Yi Xue ; 18(5): 493-8, 2009 Oct.
Artigo em Zh | MEDLINE | ID: mdl-19907856

RESUMO

PURPOSE: To study the effect of TiO2 nano-pore on titanium surface on cell biological characteristics of bone marrow stromal cells (BMSCs), such as cell adhesion and spreading. METHODS: TiO2 nano-pore structure on titanium surface with certain shape and size was prepared by electrochemical anodizing and chemical corrosion technologies. The effect of TiO2 nano-pore on titanium surface on cell adhesion, morphology, cytoskeleton protein of BMSCs was detected by laser scanning confocal microscope, scanning electron microscope. The data was analyzed by Student t test using SAS6.12 software package. RESULTS: TiO2 nano-pores were produced on titanium surface, which was of about 30nm in width and 15nm in depth. More adhesive cells, larger cell spreading area, thinker cytoskeleton, richer fine pseudopodia were observed in the treatment group than in the control group after 4 hours and 8 hours of incubation of BMSCs (P<0.05). The area of BMSCs cell spreading in treatment group was 1.35 times than in the control group (P=0.001). CONCLUSION: TiO2 nano-pores produced on titanium surface by electrochemical anodizing and chemical corrosion technologies may promote cell adhesion and spreading of BMSCs. Supported by National Natural Science Foundation of China(Grant No.30572053), Nanometer Research Project of Shanghai Municipality(Grant No. 0452nm063), Research Fund of Science and Technology Commission of Shanghai Municipality (Grant No.09DZ2271100) and Shanghai Leading Academic Discipline Project (Grant No.S30206).


Assuntos
Adesão Celular , Células-Tronco Mesenquimais , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Titânio
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